fxEPA
United States
Environmental Protection
Agency
Robert S. Kerr Environmental Research
Laboratory
Ada OK 74820
EPA-600/2-80-073
April 1980
Research and Development
Selected Irrigation
Return Flow Quality
Abstracts 1978
Eighth Annual Issue
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
-------
EPA-600/2-80-073
April 1980
SELECTED IRRIGATION RETURN FLOW
QUALITY ABSTRACTS 1978
Eighth Annual Issue
by
Gaylord V. Skogerboe
Wynn R. Walker
Satyansu S. Kundu
Mary Lindburg
Colorado State University
Fort Collins, Colorado 80523
Grant No. R-800426
Project Officer
Alvin L. Wood
Source Management Branch
Robert S. Kerr Environmental Research Laboratory
Ada, Oklahoma 74820
ROBERT S. KERR ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
ADA, OKLAHOMA 74820
-------
DISCLAIMER
This report has been reviewed by the Robert S. Kerr Environ-
mental Research Laboratory, U.S. Environmental Protection Agency/
and approved for publication. Approval does not signify that the
contents necessarily reflect the views and policies of the U.S.
Environmental Protection Agency, nor does mention of trade names
or commercial products constitute endorsement or recommendation
for use.
-------
FOREWORD
The Environmental Protection Agency was established to co-
ordinate administration of the major Federal programs designed
to protect the quality of our environment.
An important part of the Agency's effort involves the
search for information about environmental problems, management
techniques and new technologies through which optimum use of the
Nation's land and water resources can be assured and the threat
pollution poses to the welfare of the American people can be
minimized.
EPA's Office of Research and Development conducts this
search through a nationwide network of reserach facilities. As
one of these facilities, the Robert S. Kerr Environmental Re-
search Laboratory is responsible for the management of programs
to: (a) investigate the nature, transport, fate and management
of pollutants in groundwater; (b) develop and demonstrate methods
for treating wastewaters with soil and other natural systems;
(c) develop and demonstrate pollution control technologies for
irrigation return flows; (d) develop and demonstrate pollution
control technologies for animal production wastes; (e) develop
and demonstrate technologies to prevent, control or abate pollu-
tion from the petroleum refining and petrochemical industries;
and (f) develop and demonstrate technologies to manage pollution
resulting from combinations of industrial wastewaters or
industrial/municipal wastewaters.
This report provides a single source abstracted and indexed
reference of research on water quality problems of irrigation re-
turn flows and the potential technological solutions and institu-
tional constraints to solutions of those problems. The sources
abstracted include coverage of work in the United States and
other parts of the world. Current knowledge of related research
is essential if optimum use is to be made of our available re-
sources in developing reasonable, cost effective, environmentally
sound solutions to the problems encountered in the control of
water quality in return flows from irrigated agriculture.
&Ufk...>C>0
William C. Galegar
Director, Robert S. Kerr Environ-
mental Research Laboratory
iii
-------
PREFACE
The eighth annual issue of SELECTED IRRIGATION RETURN
FLOW QUALITY ABSTRACTS has been compiled from approximately 100
sources of material covering calendar year 1978. This compila-
tion has attempted to include technological and institutional
articles that would be pertinent to action programs regarding
the control of water quality degradation resulting from irrigated
agriculture.
The state-of-the-art report, "Characteristics and Pollution
Problems of Irrigation Return Flow," prepared by the Utah State
University Foundation, contains a bibliography of articles perti-
nent to Irrigation Return Flow Quality through 1967. The first
annual issue Of SELECTED IRRIGATION RETURN FLOW QUALITY ABSTRACTS
listed publications appearing in calendar years 1968 and 1969,
while the second annual issue listed publications appearing in
calendar years of 1970 and 1971, the third annual issue contained
abstracts of articles and reports published during calendar
years 1972 and 1973, and the fourth, fifth, sixth and seventh
annual issues contained abstracts of 1974, 1975, 1976 and 1977
publications. The eighth annual issue contains 787 abstracts
of documents published during calendar year 1978. The abstracts
have been placed into sections according to the category and
subgroup classifications used by the Water Resources Scientific
Information Center (WRSIC) as published in the report, "Water
Resources Thesaurus." The abstracts have been forwarded to
WRSIC for inclusion in their bi-monthly publication, "Selected
Water Resources Abstracts."
xv
-------
ABSTRACT
Research related to the quality of irrigation return flow
is being conducted at numerous institutions throughout the
western United States. Related work is also underway at other
institutions in the United States, as well as other portions of
the world. Approximately 100 sources of material have been
searched for articles pertinent to the Irrigated Crop Production
research and development program. These articles describe water
quality problems resulting from irrigated agriculture, potential
technological solutions for controlling return flows, recent
research pertinent to return flow investigations, and literature
associated with institutional constraints in irrigation return
flow quality control.
The first annual issue of SELECTED IRRIGATION RETURN FLOW
QUALITY ABSTRACTS covered publications printed in 1968 and 1969,
while the second annual issue lists publications printed in 1970
and 1971, the third annual issue covers calendar years 1972 and
1973, and the fourth, fifth, sixth and seventh annual issues
cover literature published in 1974, 1975, 1976 and 1977. This
annual issue lists publications printed in 1978. This report
was submitted in fulfillment of Grant No. R-800426 under the
sponsorship of the Office of Research and Development, U.S.
Environmental Protection Agency.
Key Words: Fertilizers, Irrigated land. Irrigation systems,
Irrigation water, Nitrates, Phosphates, Return flow, Salinity,
Water pollution effects, Water pollution sources, Water quality
control.
-------
TABLE OF CONTENTS
Foreword . . . ,
Preface . . . ,
Abstract . . . ,
Acknowledgments
- General (Group 02A)
- Precipitation (Group 02B)
- Snow, Ice, and Frost (Group 02C). . .
- Evaporation and Transpiration (Group
- Streamflow and Runoff (Group 02E) . .
- Groundwater (Group 02F)
- Water in Soils (Group 02G)
- Lakes (Group 02H)
- Water and Plants (Group 021)
- Erosion and Sedimentation (Group 02J)
- Chemical Processes (Group 02K). . . .
AUGMENTATION AND CONSERVATION -
Improvement (Group 03B)
AUGMENTATION AND CONSERVATION -
of Impaired Quality (Group 03C). . . .
AUGMENTATION AND CONSERVATION -
in Domestic and Municipal Use (Group
I WATER CYCLE
II WATER CYCLE
III WATER CYCLE
IV WATER CYCLE
02D) ....
V WATER CYCLE
VI WATER CYCLE
VII WATER CYCLE
VIII WATER CYCLE
IX WATER CYCLE
X WATER CYCLE
XI WATER CYCLE
XII WATER SUPPLY
Water Yield
XIII WATER SUPPLY
Use of Water
XIV WATER SUPPLY
Conservation
03D) ....
XV WATER SUPPLY AUGMENTATION AND CONSERVATION - Con-
servation in Agriculture (Group 03F)
XVI WATER QUANTITY MANAGEMENT AND CONTROL - Control of
Water on the Surface (Group 04A)
XVII WATER QUANTITY MANAGEMENT AND CONTROL - Ground-
water Management (Group 04B)
XVIII WATER QUANTITY MANAGEMENT AND CONTROL - Effect on
Water of Man's Nonwater Activities (Group 04C). . .
XIX WATER QUANTITY MANAGEMENT AND CONTROL - Watershed
Protection (Group 04D)
XX WATER QUALITY MANAGEMENT AND PROTECTION - Identifi-
cation of Pollutants (Group 05A)
XXI WATER QUALITY MANAGEMENT AND PROTECTION - Sources
and Fate of Pollution (Group 05B)
XXII WATER QUALITY MANAGEMENT AND PROTECTION - Effects
of Pollution (Group 05C)
XXIII WATER QUALITY MANAGEMENT AND PROTECTION - Waste
Treatment Processes (Group 05D)
XXIV WATER QUALITY MANAGEMENT AND PROTECTION - Water
Quality Control (Group 05G)
111
iv
v
ix
1
6
7
8
12
16
27
58
59
74
83
110
111
114
115
156
162
168
169
172
180
205
208
209
vii
-------
XXV WATER RESOURCES AND PLANNING - Techniques of
Planning (Group 06A) 235
XXVI WATER RESOURCES PLANNING - Evaluation Process
(Group 06B) 241
XXVII WATER RESOURCES PLANNING - Cost Allocation, Cost
Sharing, Pricing/Repayment (Group 06C) 248
XXVIII WATER RESOURCES PLANNING - Water Demand (Group
06D) 249
XXIX WATER RESOURCES PLANNING - Water Law and
Institutions (Group 06E) 250
XXX WATER RESOURCES PLANNING - Ecological Impact of
Water Development (Group 06G) 256
XXXI RESOURCES DATA - Network Design (Group 07A) .... 258
XXXII RESOURCES DATA - Data Acquisition (Group 07B) . . . 259
XXXIII RESOURCES DATA - Evaluation, Processing and
Publication (Group 07C) 271
XXXIV ENGINEERING WORKS - Structures (Group 08A) 272
XXXV ENGINEERING WORKS - Hydraulics (Group 08B) 273
XXXVI ENGINEERING WORKS - Hydraulic Machinery (Group
08C) 278
XXXVII ENGINEERING WORKS - Rock Mechanics and Geology
(Group 08E) 279
XXXVIII ENGINEERING WORKS - Materials (Group 08G) 280
XXXIX MANPOWER, GRANTS, AND FACILITIES - Education -
Extramural (Group 09A) 281
XL SCIENTIFIC AND TECHNICAL INFORMATION - Acquisition
and Processing (Group 10A) 282
XLI SCIENTIFIC AND TECHNICAL INFORMATION - Secondary
Publication and Distribution (Group IOC) 283
XLII AUTHOR INDEX 285
XLIII SUBJECT INDEX 305
viii
-------
ACKNOWLEDGMENTS
The excellent cooperation of the reading room staff at the
Engineering Research Center and the library staff at Colorado
State University has been very important in accomplishing the
work reported herein.
The scope of this literature abstracting effort has been
delineated jointly by the senior author and project officer,
Mr. Alvin L. Wood, Source Management Branch, Robert S. Kerr
Environmental Research Laboratory, Environmental Protection
Agency, Ada, Oklahoma. The cooperative efforts of the Project
Officer in meeting with project personnel and reviewing the
abstracting process have been very helpful and are sincerely
appreciated.
ix
-------
SECTION I
WATER CYCLE
GENERAL (GROUP 02A)
78:02A-001
A METHODOLOGY FOR TESTING THE ACCURACY OF YIELD PREDICTIONS FROM WEATHER-YIELD
REGRESSION MODELS FOR CORN,
Nelson, W.L., and Dale, R.F.
Purdue University, West Lafayette, Indiana, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 5, p 734-740, September-October, 1978. 5 tab,
21 ref, 2 equ.
Descriptors: Statistical models, Technology, Weather data, Regression analysis,
Corn (field), Nitrogen, Indiana, Crop production.
Analysis of variance (ANOVA) techniques were used to evaluate the accuracy of
yield predictions for corn in Indiana counties with four statistical models:
1) Thompson approach, 2) modified Thompson approach with a nitrogen technology
term, 3) a 1974 model by Leeper, Runge, and Walker and 4) a 1975 model by Dale
and Hodges. For models 1) , 2), and 4), separate versions were developed with
the particular series of weather and corn yield data for each county. All models
were used to predict yearly average corn yields for a county with data not used
to fit the regression coefficients. A significant difference among models was
detected by the ANOVA. Multiple comparison tests indicated that regression
models 2), 3), and 4) were more accurate than model 1). This result was attributed
mainly to the handling of technology or the weather-technology interaction effects
on corn yields. The trend variables used in model 1) acted to confound weather
and technology effects and create unstable regression models. Although the direct
application of the results of this study is limited to Indiana, the methodology
for testing the accuracy of yield predictions is believed to have universal
application.
78:02A-002
CALIBRATION OF HYDROLOGICAL MODEL USING OPTIMIZATION TECHNIQUE,
Manley, R.E.
Severn-Trent Water Authority, Birmingham, England.
Journal of the Hydraulics Division, Proceedings of the American Society of Civil
Engineers, Vol. 104, No. HY2, p 189-202, February, 1978. 4 fig, 3 tab, 20 ref.
Descriptors: *Optimization, *Simulation analysis, *Computer models, *Mathematical
models, Digital computers, Droughts, Algorithms, Wave velocity, Model studies,
Water resources.
Computer-based mathematical models that simulate the response of a catchment
to climatic variables have been available for more than a decade. One of the
drawbacks to the use of these models has been the difficulty of calibrating them
to a particular catchment. The catchment model HYSIM has all but four of its
parameters estimated from catchment details or hydrograph analysis; the four
are calibrated using a modified version of the Rosenbrock algorithm. The complete
model occupies about 12K words (36K bytes) of computer core storage. HYSIM was
used to produce a 44-year record for a river in England extensively used for
water supply. Despite the fact that only a limited amount of data was available,
the extended record has proven adequate for water resources analysis.
78:02A-003
SENSITIVITY OF GROUNDWATER MODELS WITH RESPECT TO VARIATIONS IN TRANSMISSIVITY
AND STORAGE,
McElwee, C.D., and Yukler, M.A.
Geological Survey, Lawrence, Kansas.
Water Resources Research, Vol. 14, No. 3, p 451-459, June, 1978. 14 fig, 15 ref.
-------
Descriptors: *Aquifers, *Groundwater, *Groundwater movement, *Model studies,
Transmissivity, Storage coefficient, Drawdown, Hydraulic conductivity, Analytical
techniques, Sensitivity analysis, Sensitivity coefficient.
Sensitivity analysis is the study of a system's response to various disturbances.
In this study, disturbances of aquifer parameters were considered. In the simu-
lation of an aquifer, the investigator must establish tolerance within which the
parameters of the physical system may vary without appreciably affectinq the model
results. By means of a first-order sensitivity formalism, it was shown how to
evaluate the perturbed hydraulic head for a small change in aquifer parameter.
An expression for the sensitivity coefficient was obtained in this study by taking
the partial derivative of the flow equation with respect to a particular parameter.
The sensitivity coefficient was evaluated either analytically or by numerical
techniques for some common models. The sensitivity formalism was applied to the
Theis equation to study the general behavior of sensitivity coefficients and to
determine the range of validity of the first-order sensitivity formalism. The
formalism also was applied to one- and two-dimensional numerical models to see
the effect of barrier and constant head boundaries. The perturbed hydraulic head
was obtained for a change of transmissivity (T) and storage coefficient (S) by
applying the first-order sensitivity formalism. This procedure should be a
valuable tool in calibrating models or establishing tolerances on T and S for a
given acceptable error in hydraulic head. In general, a + or - 20% deviation
in T or S may be handled adequately by the first-order formalism discussed in this
work.
78:02A-OQ4
MODELING NITROGEN MOVEMENT IN AGRICULTURAL WATERSHEDS,
Campbell, K.L., and Sinai, G.
Florida University, Gainesville, Department of Agricultural Engineering.
Paper No. 78-2071, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 15 p. 1 fig, 22 ref.
Descriptors: Nitrogen, Water quality, Water quality control, Model studies,
Simulation analysis, Pollutants, Pollution abatement, Agricultural watersheds,
Hydrology, Nutrient removal.
Techniques were developed to simulate nitrogen movement through agricultural
watersheds. The USDAHL-74 (USDA-ARS Tech. Bui. No. 1518) model of watershed
hydrology was used to provide the hydrologic information required to model
nitrogen movement. The ACTMO (agricultural chemical transport model USDA, ARS-
H-3) nitrate model was used as a framework for the nitrogen model. Important
components to be added to the ACTMO model are discussed.
78;02A-005
A QUASI-LINEAR SPATIALLY DISTRIBUTED CELL MODEL FOR THE SURFACE RUNOFF SYSTEM,
Diskin, M.H., and Simpson, E.S.
Technion-Israel Institute of Technology, Haifa, Israel, Faculty of Civil
Engineering.
Water Resources Bulletin, Vol. 14, No. 4, p 903-918, August, 1978. 7 fig, 3 tab,
10 ref.
Descriptors: *Surface runoff, *Watersheds (basins) , *Model studies, Precipitation
(atmospheric), Precipitation excess, Excessive precipitation, Hydrographs,
Analytical'techniques, Synthetic hydrology, Hydrology.
The paper presented a spatially distributed model consisting of cells that are
interconnected in a pattern similar to the major drainage network of the water-
shed. Each cell receives as input the rainfall excess for the area represented
by the cell as well as inflows from cells located upstream. Outflow from the
cell is derived by routing the total input through the cell assuming it to be a
linear reservoir during the storm. The time constant of the cell, however, was
allowed to vary from storm so that the model may be described as a quasi-linear
model. The model was tested with rainfall excess and direct surface runoff data
available for a medium size watershed with satisfactory results. The time
constant was found to be related to the rainfall excess of the storms studied,
its value decreasing with the increase in the total rainfall excess.
-------
78:02A-006
AN ADAPTIVE ALGORITHM FOR ANALYZING SHORT-TERM STRUCTURAL AND PARAMETER CHANGES
IN HYDROLOGIC PREDICTION MODELS,
Wood, E.F., and Szollosi-Nagy, A.
Princeton University, New Jersey, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 4, p 577-581, August, 1978. 7 fig, 34 ref,
1 append.
Descriptors: *Rainfall-runoff relationships, *Simulation analysis, *Forecasting,
*Input-output analysis, *Algorithms, *State space formulation, Environmental
effects, Kalman filters, Ombone River Basin (Italy), Noise covariances.
An adaptive unbiased recursive prediction algorithm, based on the state space
description of hydrologic systems, is discussed. Discrete linear systems with
white Gaussian disturbances are considered. The algorithm allows for short-term
structural and parameter changes due to random environmental effects. A pre-
diction model is set up from a representation of the rainfall-runoff processes
with the unknown parameters modeled by a random walk. The predictions are ob-
tained by the use of linear Kalman filters where the unknown noise covariance
matrices are also adaptively estimated. The behavior of the adaptive prediction
algorithm is illustrated by a real-world example taken from rainfall-runoff
flood forecasting.
78:02A-OQ7
CLIMATE, SOIL, AND^VEGETATION 7. A DERIVED DISTRIBUTION OF ANNUAL WATER YIELD,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 765-776, October, 1978. 10 fig,
3 tab, 13 ref, 35 equ.
Descriptors: Water yield, Water balance. Soil-water-plant relationships, Soil
moisture movement, Precipitation, Storm runoff, Infiltration, Climatic data,
Mathematical models, Stochastic processes.
The average annual soil moisture balance, as derived from the mechanics of
storm and intersto.rm soil moisture movement and from the statistics of the
climatic variables, were used to define the average annual soil moisture. This
soil moisture was used in the equation for average annual yield to give a first-
order approximation of the annual precipitation yield function. This function
was used to transform the cumulative distribution function (cdf) of annual
precipitation into the cdf of annual yield, and application was made in a sub-
humid and in an arid climate. The derived yield frequency function is seen to be
sensitive to the soil and vegetal properties. Proper selection of these para-
meters brought close agreement-with observed streamflow-frequency and suggested
the model's utility for parameterizing drainage basins with respect to effective
average soil and vegetal properties.
78:02A-008
CLIMATE, SOIL, AND VEGETATION 6. DYNAMICS OF THE ANNUAL WATER BALANCE,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 749-764, October, 1978. 11 fig,
4 tab, 20 ref, 74 equ'.
Descriptors: Water balance, Soil-water-plant relationships, Precipitation
(atmospheric), Evapotranspiration, Surface runoff, Groundwater, Climatic data,
Moisture deficit, Mathematical models.
Mass conservation was employed to express the natural water balance of climate-
soil-jvegetation systems in terms of the average annual values of precipitation,
evapotranspiration, surface runoff, and groundwater runoff as derived from the
probability distributions of storm properties and from the physics of the
appropriate storm and interstorm soil moisture fluxes. The resulting conserva-
tion equation was used to define the diroensionless parameters governing the
dynamic similarity of the annual water balance. An asymptotic analysis of this
water balance equation yielded a set of rational criteria for the classification
of climate-soil-vegetation systems. Sensitivity with respect to the primary
climate, soil, and vegetal parameters demonstrated that qualitative changes in
-------
water balance behavior are primarily dependent upon the exfiltration
effectiveness of the soil. A natural selection hypothesis was presented which
specified the stable vegetation density and the plant coefficient for a given
climate-soil system in which water and not nutrition or light was limiting.
7&:02A-009
CLIMATE, SOIL, AND VEGETATION 5. A DERIVED DISTRIBUTION OF STORM SURFACE
RUNOFF,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 741-748, October, 1978. 6 fig,
2 tab, 11 ref, 76 equ.
Descriptors: Storm runoff, Climatic data, Soil properties, Vegetation, Rainfall-
runoff relationships, Soil moisture, Rainfall intensity, Infiltration, Flood
discharge, Mathematical models.
The Philip infiltration equation was integrated over the duration of a rainstorm
of uniform intensity to give the depth of point surface runoff from such an
event on a natural surface in terms of random variables defining the initial
soil moisture, the rainfall intensity, and the storm duration. In a zeroth-
order approximation the initial soil moisture was fixed at its climatic space
and time average, whereupon by using exponential probability density functions
for storm intensity and duration, the probability density function of point
storm rainfall excess was derived. This distribution was used to define the
annual average depth of point surface runoff and to derive the flood volume fre-
quency relation, both in terms of a set of physically meaningful climate-soil
parameters.
78:02A-010
HYDROLOGIC MODELING OF SMALL WATERSHEDS IN ASAE MONOGRAPH,
Haan, C.T.
Oklahoma State University, Stillwater, Department of Agricultural Engineering.
Paper No. 78-2588, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 5 p.
Descriptors: Hydrologic cycle, Small watersheds, Model studies, Hydrology,
Stochastic processes, Hydrologic properties, Groundwater, Soil water movement,
Evapotranspiration, Soil erosion.
This monograph has 13 chapters devoted to modeling of the hydrplogic cycle on
small watersheds. Primary emphasis is on basic approaches to modeling the
various parts of the hydrologic cycle, on combining component models into
hydrologic models and on selecting and testing hydrologic models.
78:02A-011
SIMULATED STREAMFLOW RESPONSE TO POSSIBLE DIFFERENCES IN TRANSPIRATION AMONG
SPECIES OF HARDWOOD TREES,
Federer, C.A., and Lash, D.
Northeastern Forest Experiment Station, United States Department of Agriculture,
Forest Service, Durham, New Hampshire 03824.
Water Resources Research, Vol. 14, No. 6, p 1089-1097, December, 1978. 8 fig,
4 tab, 17 ref.
Descriptors: Streamflow, Transpiration, Hydrologic cycle, Model studies,
Simulation analysis, Hardwood, Forest watersheds, Watershed management, Equation,
Evapotranspiration, Hydrologic.
Possible differences in transpiration among species of hardwood trees were
simulated in a hydrologic model, called Brook, to estimate the effects of these
differences on monthly and annual streamflow. Brook is a deterministic, lumped-
parameter model that simulated streamflow from small, forested watersheds in
the eastern United States. The model uses only daily mean temperature and daily
precipitation as input. A 4-week difference in timing of leaf-development in
spring or color change in autumn caused differences of 10-60 mm in simulated
annual streamflow. When daily transpiration varied by 20%, as it might with
-------
differences in leaf diffusive resistance among species, differences in simulated
streamflow ranged from 15 to 120 mm annually. Differences in root distribution
with depth can affect the availability of soil water; varying this availability
caused differences in simulated streamflow of 15-60 mm. In all cases the smaller
differences occurred when the soil was dry at the times of differing transpiration.
On a deep residual soil the differences in streamflow were spread through the year,
but on a shallow till soil the differences were restricted to the months in which
there were changes in transpiration. Differences in response among 15 degrees
north-facing and 15 degrees south-facing slopes and a horizontal surface were
minor.
-------
SECTION II
WATER CYCLE
PRECIPITATION (GROUP 02B)
78:028-001
CLIMATE, SOIL, AND VEGETATION 2. THE DISTRIBUTION OF ANNUAL PRECIPITATION DERIVED
FROM OBSERVED STORM SEQUENCES,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 713-721, October, 1978. 12 fig,
1 tab, 11 ref, 54 egu.
Descriptors: Precipitation (atmospheric), Distribution, Storms, Rainfall, Statis-
tical methods, Probability, Stochastic processes.
Point precipitation was represented by Poisson arrivals of rectangular intensity
pulses that have random depth and duration. By assuming the storm depths to
be independent and identically gamma distributed, the cumulative distribution
function for normalized annual precipitation was derived in terms of two para-
meters of the storm sequence, the mean number of storms per year and the order
of the gamma distribution. In comparison with long-term observations in a sub-
humid and an arid climate it was demonstrated that when working with only 5 years
of storm observations this method tends to improve the estimate of the variance
of the distribution of the normalized annual values over that obtained by con-
ventional hydrologic methods which utilize only the observed annual totals.
-------
SECTION III
WATER CYCLE
SNOW, ICE, AND FROST (GROUP 02C)
78:020-001
WATER REDISTRIBUTION IN PARTIALLY FROZEN, SATURATED SILT UNDER SEVERAL
TEMPERATURE GRADIENTS AND OVERBURDEN LOADS,
Loch, J.P.G., and Kay, B.D.
Guelph University, Ontario, Department of Land Resources Science.
Soil Science Society of America Journal, Vol. 42, No. 3, p 400-406, May-June,
1978. 7 fig, 2 tab, 17 ref.
Descriptors: *New Hampshire, *Freezing, *Soil water, *Crystal growth, *Frost
heaving, *Cryogenics, Thermocline, Saturated flow, Model studies, Gamma
scanning system.
The flux of water and the resultant formation of discrete ice lenses were studied
in samples of New Hampshire silt which were saturated and then frozen under
different temperature gradients and overburden pressures. A dual energy gamma
scanning system was employed to locate the position of the growing ice lens rela-
tive to the freezing front. Parameters controlling water flow and the location
of the ice lenses were employed to evaluate theories that have been proposed to
describe the mechanisms of ice lens formation. The capillary theory was employed
to locate the freezing front. However, the ice lenses were found to be located
0.2-0.4 cm behind the freezing front, which is inconsistent with the location
of the ice lenses predicted by the capillary theory. Neither the hydrodynamic
theory nor the secondary frost heaving theory account for the redistribution of
overburden pressure between soil particles, ice, and water. These theories
cannot be employed to predict the location of the ice lens relative to the
freezing front until overburden pressure effects are incorporated into the theory.
-------
SECTION IV
WATER CYCLE
EVAPORATION AND TRANSPIRATION (GROUP 02D)
78:020-001
THE DISHONEST METHOD IN STREAM TEMPERATURE MODELING,
Morse, W.L.
Bonneville Power Administration, Portland, Oregon.
Water Resources Research, Vol. 14, No. 1, p 45-51, February, 1978. 1 tab, 18 ref.
Descriptors: *Water temperature, *Streams, *Model studies, *Mathematical models,
Stochastic processes, Mathematics, Statistics, Solar radiation. Hydrology,
Heat transfer.
The unidimensional form of the thermal energy conservation principle as a quasi-
linear partial differential equation (PDE) has been shown accurate for point
temperature forecasts on completely mixed streams and river-run reservoir systems.
Two methods of solution were presented which lead to a unique solution. Yet this
nonrandom solution was contrary to the behavior of nature, and so a philosophic
change was introduced. From the PDE subsidiary differential system a stochastic
differential equation (SDE) was obtained with random forcing function from the
meteorologic and forebay-depth analyses. With random intial conditions (time-
averaged components of the in situ water temperature vector), the SDE was recasted
as a random nonlinear Volterra integral equation (RIE). Then a solution to the
random-initial-conditions RIE (fixed points of the expectations) by the so-called
dishonest method was compared with a solution obtained by repetitively solving
the PDE as a random equation (expectations of the fixed points). Of course,
these solutions, obtained by "dishonest and honest" methods, are not necessarily
unique, but they may be sufficiently close in some sense. Hence, proper inter-
pretation and use of this RIE model would enable water resource planners to
determine economically stream temperatures in probability during critical climatic
or river flow conditions. And then intelligent planning and scheduling could
avoid some catastrophic aquatic event which might occur as a result of extreme
water temperatures.
78:020-002
EVALUATION OF EVAPORATION FROM LAKE ONTARIO DURING IFYGL BY A MODIFIED MASS
TRANSFER EQUATION,
Phillips, D.W.
Atmospheric Environment Service, Downsview, Ontario, Hydrometeorology and Marine
Applications Division.
Water Resources Research, Vol. 14, No. 2, p 197-205, April, 1978. 4 fig, 4 tab,
28 ref.
Descriptors: *Evaporatlon, *Lake Ontario, *Great Lakes, *International field
year, *Lake Hefner, Turbulent energy flux, Multi-regression equations, Hydrologic
budget, Stability, Meteorology.
Daily evaporation from Lake Ontario during the International Field Year for the
Great Lakes (.April, 1972 to March, 1973} was computed by a modified/mass transfer
technique. Turbulent energy flux was calculated by using upwind land station
data and the surface water temperature at 88 grid points on the lake. Wind
speed and humidity at each grid point were determined through multi-degression
equations that took into account stability, fetch, and water temperature.. Daily,
monthly, and annual evaporation amounts obtained by this study were compared
to amounts obtained by conventional mass transfer, energy balance, and terrestrial
water budget methods, discrepancies in the results of the various approaches were
examined and discussed.
-------
78:020-003
ESTIMATING EVAPOTRANSPIRATION RATES FOR CORN IN DELAWARE,
Ritter, W.F., Williams, T.H., and Eastburn, R.P.
Delaware University, Newark, Department of Agricultural Engineering.
Paper No. 78-2029, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 27 p. 17 fig, 1 tab,
11 ref.
Descriptors: Evapotranspiration, Estimating, Humid climates, Corn (field),
Meteorological data, Growth stages, Consumptive use, Delaware.
The Jensen-Haise, Penman, pan evaporation and Thornthwaite methods were used
to predict evapotranspiration. All methods underestimated the measured peak ET
rates. The critical moisture period for corn was found to be from the 14th leaf
stage to beginning dent.
78:02D-004
EVAPOTRANSPIRATION FROM WATER HYACINTH IN TEXAS RESERVOIRS,
Benton, A.R., Jr., James, W.P., and Rouse, J.W.
Texas A * M University, College Station, Department of Civil Engineering.
Water Resources Bulletin, Vol. 14, No. 4, p 919-930, August, 1978. 3 fig, 3 tab,
21 ref.
Descriptors: *Evapotranspiration, *Water hyacinth, *Reservoirs, *Water loss,
*Texas, *Texas Water plan. Floating plants, Vegetation effects, Aquatic plant
control, Aquatic weeds.
Water hyacinth, an attractive, floating aquatic plant, poses a substantial
threat of unanticipated water loss from Texas reservoirs. A mature plant will
lose about three times as much water through evapotranspiration as is lost from
evaporation of an equivalent area of open water. The reservoirs of east and
southeast Texas, which comprise the bulk of the state's existing and planned
water storage capacity, seem likely to suffer a 20% average surface infestation
of water hyacinth. A coverage that great will result in a yearly net loss of
over 2,000,000 acre-feet of impounded water, based on present water development
plans for the state. This would amount to nearly 20% of the anticipated yield
from the reservoirs affected. An effective aquatic plant control program could
head off the threat of this significant water loss.
78:02D-005
CLIMATE, SOIL, AND VEGETATION 4. THE EXPECTED VALUE OF ANNUAL EVAPOTRANSPIRATION,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 731-739, October, 1978. 6 fig,
24 ref, 53 equ.
Descriptors: Evapotranspiration, Water balance, Infiltration, Soil moisture
movement, Climatic data, Soil properties, Vegetation, Mathematical models,
Surface runoff.
The depth of interstorm evapotranspiration from natural surfaces was composed
(by proportion to vegetal canopy density) of evaporation from bare soil and
transpiration from vegetation. The former was obtained in terms of random
variables describing initial soil moisture, time between storms, and potential
rate of evapotranspiration from an exfiltration analogy to the Philip infiltra-
tion equation modified to incorporate moisture extraction by plant roots. The
latter was assumed to occur at the potential rate for natural vegetal systems.
In a zeroth-order approximation the initial soil moisture was fixed at its cli-
matic space and time average whereby using an exponential distribution of time
between storms and a constant potential rate of evapotranspiration the expected
value of interstorm evapotranspiration was derived. This mean value was used
to obtain the annual average point- evapotranspiration as a fraction of the
potential value and as a function of dimensionless parameters defining the
climate-soil-vegetation system.
-------
78:020-006
A COMPARISON OF TWO FORMULA TYPES FOR CALCULATING LONG-WAVE RADIATION FROM THE
ATMOSPHERE,
Aase, J.K., and Idso, S.B.
Northern Plains Soil and Water Research Center, Sidney, Montana.
Water Resources Research, Vol. 14, No. 4, p 623-625, August, 1978. 1 fig, 1 tab,
14 ref, 3 equ.
Descriptors: Radiation, Thermal radiation, Solar radiation, Air temperature,
Humidity, Vapor pressure, Estimating equations.
Measurements of long-wave radiation at Sidney, Montana, indicated that both an
analytically derived equation and an empirically derived equation for clear-sky
conditions adequately predict the long-wave radiation flux at that site for
screen level air temperatures above 0°C. However, for air temperatures below
0°C, the analytical equation always underestimated the true radiation, while the
empirical equation just slightly underestimated it, then match it, and then over-
estimated it, as air temperature decreased from 0°C to -37°C. These discrepancies
in the below 0°C temperature regime indicated that the equations might need some
modification to conform more closely to reality for low-temperature conditions.
78:020-007
THE ROLE OF EVAPOTRANSPIRATION MODELS IN IRRIGATION SCHEDULING,
Jensen, M.E., and Wright, J.L.
Snake River Conservation Research Center, United States Department of Agriculture-
Agricultural Research Service, Kimberly, Idaho.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21 SW, No. 1, p 82-87, February 20, 1978. 4 fig, 2 tab, 25 ref, 3 equ.
Descriptors: Scheduling, Irrigation, Evapotranspiration, Model studies, Soil
moisture, Statistical methods.
Most evapotranspiration (ET) models are based on physical principles controlling
evaporation and the conservation of mass and energy, and use daily climatic data.
ET models coupled with irrigation models are valuable tools because they enable
trained and experienced irrigation specialists to provide irrigation scheduling
services at a reasonable cost. Estimated standard deviations of mean daily ET
for 1- to 30-day periods at Akron, Colorado; Davis, California; Kimberly, Idaho;
and Lompoc, California varied from 0.9 to 1.3 mm/day and it decreased to 0.4 to
0.7 mm/day for 15- to 30-day periods. Standard errors of ET estimates with a
combination equation based on 243 days of data from Kimberly, Idaho were normally
distributed and for daily values was 1.0 mm/day. This parameter decreased in-
versely with the square root of the number of days for up to 30 days and was
similar to those reported for other areas using models that operate on daily
climatic data. A summary of factors affecting confidence levels in irrigation
scheduling was presented along with the expected standard deviations. Generally,
the error in measuring soil moisture was generally smaller than estimated ET
and irrigation application errors.
78:020-008
DEVELOPMENT AND EVALUATION OF EVAPOTRANSPIRATION MODELS FOR IRRIGATION SCHEDULING,
Wright, J.L., and Jensen, M.E.
Snake River Conservation Research Center, Kimberly, Idaho.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No.' 1, p 99-91, 96, February 20, 1978. 6 fig, 1 tab, 7 ref, 4 equ.
Descriptors: Evapotranspiration, Model studies, Scheduling, Irrigation,
Lysimeters, Soil water.
Evapotranspiration (ET) data for irrigated crops in southern Idaho were used to
develop relationships for estimating net radiation and potential ET for the
USDA-ARS Computerized Irrigation Scheduling Program. ET estimated with the
initial relationships compared well with recent measurements obtained with two
sensitive weighing lysimeters. The average daily measured ET for alfalfa for
128 days when there was full cover was 7.23 mm, while the average daily estimated
ET was 7.15 mm. Crop curve relationships were developed from the ET results for
snap beans CPhaseolus vulgaris L.). The depletion of soil water was predicted
10
-------
for two years of irrigated beans with the scheduling program using the improved
crop curves and compared with the measured as a test of its performance. The
standard deviation of the difference between predicted and measured was about
0.95 mm/day from planting until harvest. The results also demonstrated the
importance of obtaining representative meteorological data for irrigation
scheduling.
11
-------
SECTION V
WATER CYCLE
STREAMFLOW AND RUNOFF (GROUP 02E)
78:02E-001
SOME PROPERTIES OF VARIANCE REDUCTION TECHNIQUES WHERE HYDROLOGICAL EXTREMES
ARE ESTIMATED BY MONTE CARLO SIMULATION,
Moore, R.J., and Clarke, R.T.
Institute of Hydrology, Wallingford, England.
Water Resources Research, Vol. 14, No. 1, p 55-61, February, 1978. 8 tab, 11 ref.
Descriptors: *Streamflow, *Model studies, *Mathematical models, *Monte Carlo
method, *Synthetic hydrology, *Variance reduction, *Hydrological extremes,
Regression analysis, Estimating, Probability.
An estimate F of a water resource system's performance, when it is derived by
simulation using synthetic sequences, is subject to at least three errors; first,
model errors, arising from the approximation to the "true" streamflow mechanism
which the model represents; second, sampling errors in the model parameters theta
when they are calculated from the historic records; and third, errors introduced
by the Monte Carlo calculation from which F is derived. This paper presented
some observations on the effects of the first two types of error on the estimate
F but concentrated on the application of variance reduction techniques to the
derivation of Monte Carlo estimates F for given theta. These techniques were,
first, the use of control variates, and second, the use of antithetic variates.
The application of the technique was illustrated by using some hypothetical
examples of the calculation of probabilities of extreme hydrological events and
of the calculation of reliability measures for a much oversimplified storage sy-
stem. Considerable reduction in the variance of F resulted from the application
of the control variate method; the reduction in Var F resulting from the use of
antithetic variates was much less but still probably worth the small additional
programming effort required. It was concluded that the promise of the control
variate method suggests that it should be applied to assist in the efficient
simulation of more realistic water resource systems than the trivial ones
considered in this paper.
78:02E-002
A UNIFYING SET OF PROBABILITY TRANSFORMS FOR STOCHASTIC HYDROLOGY,
Snyder, W.M., Mills, W.C., and Knisel, W.G., Jr.
Agriculture Research Service, Athens, Georgia, Southeast Watershed Laboratory.
Water Resources Bulletin, Vol. 14, No. 1, p 83-98, February, 1978. 9 fig, 3 tab,
6 ref.
Descriptors: *Synthetic hydrology, *Statistics, *Probability, Model studies,
Storms, Floods, Design storm, Statistical methods. Stochastic processes,
Lognormal distributions.
An ordered set of probability density functions was derived from transforms of
the normal distribution. Variate transforms were based on orders of exponentia-
tion. The set of distributions included the log-normal. A partial basis for
use of these functions in hydrology was demonstrated by establishing some
required properties. A concept of mixed samples of zero and nonzero elements
forming nonseparable sets of virtual and real elements was introduced to esta-
blish a physical lower limit of samples data independent of functional bounds.
78:02E-003
RIVER TRANSPORT MODELING FOR UNSTEADY FLOWS,
Reefer, T.N., and Jobson, H.E.
Sutron Corporation, Arlington, Virginia.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
104, No. HY5, Proceedings Paper 13735, p 635-647, May, 1978. 4 fig, 1 tab,
9 ref, 2 append.
12
-------
Descriptors: *Streamflow, *Unsteady flow, *Mass transfer, *Georgia,
*Chattahoochee River (Georgia), Model studies, Dye releases, River flow,
Dispensing, Hydraulics.
Coupled flow-mass transport models were applied to a 17-mile (27.8-km) reach
of the Chattahoochee River between Buford and Norcross, Georgia. Discharge
variations from 550 cfs to 8,000 cfs (15 cu m/s to 100 cu m/s) in less than 20
min were analyzed. Accompanying stage variations were as much as 7 ft (2 m).
Two data sets with 5-min time resolution were used to calibrate and verify the
flow model. A longitudinal depth profile at steady low flow also was used in
the calibration. Data from a 3-day continuous-injection dye study were used to
verify the mass-transport model. The study demonstrated the feasibility of
coupled models under highly unsteady flow conditions. The dye study demonstrated
the unusual nature of conservative mass transport in unsteady flow. Both the
flow and mass-transport models produced answers approaching the accuracy of the
data. These are estimated as + or - 29 min in time, + or - 15%-20% for discharge,
and + or - 0.5-ft (0.1-m) for stage.
78:02E-004
PRESERVATION OP THE RESCALED ADJUSTED RANGE 3. FRACTIONAL GAUSSIAN NOISE
ALGORITHMS,
Hipel, K.W., and McLeod, A.I.
Waterloo University, Ontario, Department of Systems Design.
Water Resources Research, Vol. 14, No. 3, p 517-518, June, 1978. 14 ref.
Descriptors: *Computer models, *Mathematical models, *Hydrology, *Fractional
Gaussian noise algorithms, *Rescaled adjusted range, Hurst coefficient,
Time series analysis, Stochastic processes, Streamflow, Model studies.
Improved modeling procedures are available for use with a discrete time fractional
Gaussian noise (FGN) model. These advancements in FGN modeling consist of an
exact simulation procedure, a maximum likelihood approach to obtain efficient
stimates of the model parameters, and a technique for calculating the model
residuals so that they can be subjected to rigorous diagnostic checks. The
computer algorithms for the aforementioned modeling improvements are available
on microfiche. The intention of this article was 'to summarize the essential
ingredients of the complete paper, which appears on microfiche.
78;02E-005
STREAM TEMPERATURE ESTIMATION USING KALMAN FILTER,
Chiu, C-L., and Isu, E.G.
Pittsburgh University, Pennsylvania, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY9, p 1257-1268, September, 1978. 4 fig, 16 ref, 33 equ, 2 append.
Descriptors: Water temperature, Streams, Mathematical models, Streamflow,
Estimating, Forecasting, Stochastic processes.
The technique presented in this paper for estimating the daily Streamflow tempera-
ture uses the Kalman filtering in which an observation and a (mathematical)
system models were combined. The mathematical system model in turn combined a
deterministic sinusoidal temperature model with a simple, stochastic (first-
order autonegressive) model used to deal with the random deviation, from the
actual temperature, of the temperature estimation given by the sinusoidal model.
In this study the estimation and forecasting technique was tested for its capa-
bility to generate (predict or estimate) daily Streamflow temperatures between
measurements at several different measurement intervals ranging from 2 days to
15 days. The estimated temperatures were compared with the observed. The results
showed several advantages of using Kalman filter over other existing models.
78:02E-006
CLIMATE, SOIL AND VEGETATION 5. A DERIVED DISTRIBUTION OF STORM SURFACE RUNOFF,
Eagleson, P.s.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 741-748, October, 1978. 6 fig, 2 tab,
11 ref, 76 equ.
(See 78:02A-009)
13
-------
78:02E-007
A FEATURE PREDICTION MODEL IN SYNTHETIC HYDROLOGY BASED ON CONCEPTS OF PATTERN
RECOGNITION,
Panu, U.S., and Unny, T.E.
Waterloo University, Ontario, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 2, p 335-344, April, 1978. 7 fig, 4 tab,
23 ref.
Descriptors: *Synthetic hydrology, *Hydrologic data, *Modelstudies, *Stochastic
processes, *Feature prediction model, *Saskatchewan River, Pattern recognition,
Time series analysis, Methodology, Hydrology.
It is reasonable to consider that sequences of hydrologic data corresponding to
daily, weekly, or monthly measurements occur in well-defined groups. These
groups possess collective properties of the data forming them. Such a cbl-lection
of properties can be called a hydrologic pattern. A pattern is a description
of an object; and the objects of concern in this paper were groups of data on
hydrologic phenomena observed at regular time intervals. Hydrologic patterns
describing each of these groups are expressed by n appropriate properties.
Further, the dimensionality, n in number, can be reduced by considering only
those characteristic properties, m in number ( m less than or = to n), that
are common in all hydrologic patterns of the same category. These m characteris-
tic properties are called features. A procedure was presented to extract infor-
mation present within patterns and among patterns of the pertinent hydrologic
data. In addition, on the basis of the above information, a zero-order Markov
feature prediction model was postulated. The basic assumptions of the model and
their implications were presented. The model was applied to South Saskatchewan
River flow data in an effort to demonstrate its usefulness in real situations.
78:02E-OQ8
PRESERVATION OF THE RESCALE ADJUSTED RANGE 1. A REASSESSMENT OF THE HURST
PHENOMENON,
McLeod, A.I., and Hipel, K.W.
University of Western Ontario, London, Department of Mathematics.
Water Resources Research, Vol. 14, No. 3, p 491-508, June, 1978. 8 fig, 10 tab,
67 ref.
Descriptors: *Model studies, *Mathematical models, *Hydrology, *Rescaled adjusted
range. Stochastic processes, Mathematics, Streamflow, River flow, Time series
analysis. Simulation analysis.
Previous research related to the controversial Hurst phenomenon was reviewed and
evaluated. Because of the inherent statistical properties of the rescaled ad-
justed range (RAR) statistic, it was suggested that research primarily be devoted
to this statistic rather than to the various definitions of the Hurst coefficient.
Simulation studies revealed that for independently distributed random variables
the RAR does not depend significantly on the underlying distribution of the ran-
dom variables but is a function of the sample size. For modeling correlated
data,, the statistical attributes of a discrete fractional Gaussian noise (FGN)
process were studied and also improved. An efficient maximum likelihood estima-
tion technique was developed for the FGN model, and it was shown how the resi-
duals of the fitted model can be calculated and then subjected to diagnostic
checks. An exact simulation procedure was developed for simulating FGN in such
a way that, synthetic traces from the model lie outside the Brownian domain. The
Akaike information criterion (AIC) was suggested as a method for choosing bet-
ween a FGN and a Box-Jenkins model. For the six annual river flow series that
were considered, the AIC selected the best Box-Jenkins model in preference to
the FGN process for each data set. Because Box-Jenkins models can be shown to
preserve the historical RAR, in many practical applications it may be advantageous
to use a Box-Jenkins model instead of a FGN process.
78:02E-009
PRESERVATION OF THE RESCALED ADJUSTED RANGE 2. SIMULATED STUDIES USING BOX-
JENKINS MODELS,
Hipel, K.W., and McLeod, A.I.
Waterloo University, Ontario, Department of Systems Design.
Water Resources Research, Vol. 14, No. 3, p 509-516, June, 1978. . 6 tab, 34 ref.
14
-------
Descriptors: *Model studies, *Mathematical models, *Hydrology, *Box-Jenkins
models, *Rescaled adjusted range, Stochastic processes, Mathematical studies,
Monte Carlo method, Time series analysis, Geophysics.
It was demonstrated that autoregressive moving average (Arma) models do preserve
the rescaled adjusted range (RAR), or equivalently the Hurst coefficient K.
Arma models were fitted to 23 geophysical time series, and by using Monte Carlo
techniques and a specified statistical test it was' shown that the observed RAR
or K is retained by the models. The empirical cumulative distribution function
(ECDF) for these statistics can be calculated as closely as is required to the
theoretical distribution. Furthermore, the distribution of the RAR is a function
of the time series length N and the parameter values of the particular Arma
process being considered. Various estimates for the Hurst coefficient were com-
pared for the 23 geophysical data sets.
78:02E-010
DISCHARGE-DEPTH EQUATION FOR SHALLOW FLOW,
Turner, A.K., Langford, K.J., Win, M., and Clift, T.R.
Melbourne University, Parkville, Australia, Department of Civil Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR1, Proceedings Paper 13626, p 95-110, March, 1978.
9 fig, 3 tab, 20 ref, 2 append.
Descriptors: *Flow, *0verland flow, *Roughness (hydraulic), *Model studies,
Vegetation, Crops, Soils, Sheet flow, Retardance, Surface runoff, Equations.
The application of a discharge-depth equation (with variable coefficient and
exponent) was recommended for shallow flows of water over soil and through
vegetation. The more flexible nature of this equation over the commonly used
channel flow equations was considered, and typical values were given for three
conditions, viz, bare uneven soil, artificial vegetation, and pasture and crop
covers growing on a sandy soil.
78:02E-011
RESIDUE AND TILLAGE EFFECTS ON SCS RUNOFF CURVE NUMBERS,
Rawls, W.J., and Onstad, C.A.
Hydrology Laboratory, Science and Education Administration, Agricultural
Research, Beltsville, Maryland, United States Department of Agriculture.
Paper No. 78-2505, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 18 p. 5 fig, 7 tab, 22 ref.
Descriptors: Runoff, Surface runoff, Soil conservation, Till, Rainfall,
Simulated rainfall, Estimating, Small watersheds. Corn (field), Grains (crops).
Data from 525 simulated and natural rainfall events were used to develop guides
for estimating the effect of conservation tillage practices on the SCS runoff
curve numbers for corn and small grain. The amount of residue on the ground or
the percent of surface covered with residue was used to represent the effect
of conservation tillage practices.
15
-------
SECTION VI
WATER CYCLE
GROUNDWATER (GROUP 02F)
78:02F-001
POROUS MEDIA TESTS OF GROUNDWATER MOUNDS,
Mousavi, S.-F., Kirkham, D.
Iowa State University, Ames, Department of Agronomy.
Soil Science Society of America Journal, Vol. 125, No. 3, p 160-164, March,
1978. 8 fig, 14 ref.
Descriptors: *Model studies, *Porous media, *Groundwater recharge, Pit recharge,
Equations, Testing, Laboratory tests, Hydraulic conductivity, Infiltration,
Groundwater mounds.
To test the theoretical equations for the shapes of groundwater mounds formed
under rectangular and circular recharge basins, two Plexiglas laboratory models
were constructed. Glass beads, white silica sand, and gravel were used as porous
media, and a 60% glycerol-water mixture was used as the recharge fluid. The
mound heights, measured at various distances from the centers of the mounds, were
compared with the theoretical mound heights. The experimental mound heights
showed good agreement with theoretical ones, both for the two-dimensional and
the three-dimensional axial symmetric mounds.
78:02F-002
EFFECTS OF CORN STOVER, MANURE, AND NITROGEN ON SOIL PROPERTIES AND CROP YIELD,
Ketcheson, J.W., and Beauchamp, E.G.
Guelph University, Canada, Department of Land Resource Science.
Agronomy Journal, Vol. 70, No. 5, p 792-797, September^October, 1978. 4 fig,
8 tab, 6 ref.
Descriptors: Nitrogen, Fertilizers, Corn (field), Organic matter, Farm wastes,
Soil properties, Crop response, Soil treatment.
Residues and farmyard manures are considered important in determining the N
fertilizer requirement of crops. This relationship was studied in a 10-year
field experiment on a Typic Hapludalf soil (pH 7.8). Five levels of fertilizer
N were applied annually with three management treatments which included 1) return-
ing the stover produced by the preceding corn (Zea mays L.) crop, 2) poultry
manure equivalent to 112 kg N/ha/year and 3) no stover returned or manure applied.
Dry matter yields and N in grain and stover were measured each year. In general,
the manure treatment without N fertilizer gave yields comparable with any other
treatment. Where fertilizer N was applied, stover resulted in slightly higher
yields than where stover was removed. Stover returned to the soil did not in-
crease fertilizer N requirements at normal rates of application. It was con-
cluded that corn stover residue did not affect the N fertilizer requirement of
this soil for grain corn production. Annual applications of liquid poultry
manure, containing N equivalent to 112 kg/ha, precluded a requirement for ferti-
lizer N.
78:02F-003
AN APPROXIMATE DIFFERENTIAL EQUATION TO DESCRIBE LEAKY AQUIFER BEHAVIOR DURING
INTERMEDIATE AND LARGE VALUES OF TIME,
Rodarte, L.
Universidad Nacional Autonoma de Mexico, Mexico City, Department of Ingeniera.
Water Resources Research, Vol. 14, No. 1, p 39-44, February, 1978. 6 fig, 12 ref.
16
-------
Descriptors: *Aquifers, *Groundwater, *Model studies, ~*Leaky aquifers. Mathe-
matical models. Equations, Leakage, Flow, Pumping, Drawdown.
In analyzing a leaky aquifer for application in regional studies, it is of great
interest to have available simplified mathematical representations from which an
analogical or digital model of the problem can be constructed. In this paper, a
differential equation valid for intermediate and large values of time was pro-
posed. Also, an analytical solution corresponding to an isolated well as a test
of the range of applicability of the proposed equation was obtained.
78:02F-004
THEORY AND NUMERICAL ANALYSIS OP MOVING BOUNDARY PROBLEMS IN THE HYDRODYNAMICS
OF POROUS MEDIA,
Nakano, Y.
Cold Regions Research and Engineering Laboratory, Hanover, New Hampshire.
Water Resources Research, Vol. 14, No. 1, p 125-134, February, 1978. 4 fig, 5
tab', 14 ref.
Descriptors: *Mathematical studies, *Theoretical analysis, *Numerical analysis,
*Boundaries (surfaces), *Porous media, Equations, Groundwater movement, Moving
boundaries.
The exact mathematical description of a boundary between unsaturated flow and
saturated flow as well as a wetting front were obtained. A new concept for
numerical analysis of flow in partly unsaturated and partly saturated porous
medium was introduced. A boundary of infinitesimal width intersecting the unsat-
urated and saturated parts was substituted by an artificial transitional zone of
finite width for computational simplicity. The concept was proved to be theo-
retically justificable. The feasibility of the concept was demonstrated as it
was applied to a two-dimensional finite difference solution of a special problem
of column drainage, for which an analytical solution was obtained.
78:02F-005
LAS VEGAS VALLEY WATER BUDGET: RELATIONSHIP OF DISTRIBUTION, CONSUMPTIVE USE,
AND RECHARGE TO SHALLOW GROUNDWATER,
Patt, R.O.
Desert Research Institute, Las Vegas, Nevada 89109.
Publication No. EPA-600/2-78-159, July, 1978. 61 p, 16 fig, 8 tab, 19 ref, 3
append.
Descriptors: Groundwater, Groundwater recharge, Water' consumption.
Estimates of quantity and geographic distribution of recharge to the shallow
groundwater zone from water use return flows in Las Vegas Valley were made for
the years 1973, 1965, 1958, 1950, and 1943 as part of a broader study on the
impact of water and land use on groundwater quality. Considered components of
water use in Las Vegas Valley include the following: supply from surface and
groundwater; agriculture using potable water; agriculture using sewage effluent;
residential lawn watering; lawn watering of parks, schools, cemetaries, hotels,
motels; golf courses using potable water; golf courses using sewage effluent
water; septic tank recharge; evaporative coolers; system losses' industrial use;
power plant cooling; swimming pool use; consumptive use by phreatophytes; in-
valley recharge from precipitation, and "unaccounted for water". Consumptive
use of plants was calculated through use of the Blaney-Criddle method as 3.47
feet per year and recharge was assumed to be the difference between applied
water and calculated consumptive use. Data developed during this study indi-
cates consumptive use as determined by this method could be low by 1.5 to 2 feet
per year, and thus the following estimates of recharge to the groundwater system
are considered maximum, in acre feet: 1973-39,000; 1965-27,600; 1958-26,650;
1950-13,000; and 1943-21,000.
78:02F-006
NUMERICAL MODEL FOR SATURATED-UNSATURATED FLOW IN DEFORMABLE POROUS MEDIA.
2. THE ALGORITHM,
Narasimhan, T.N., Witherspoon, P.A., and Edwards, A.L.
California University, Berkeley, Lawrence Berkeley Laboratory.
Water Resources Research, Vol. 14, No. 2, p 255-261, April, 1978. 3 fig, 8 ref.
17
-------
Descriptors: *Numerical analysis, *Mathematical models, *Porous media, *Satur-
ated flow, *Unsaturated flow, *Algorithms, *Integrated-finite-difference method,
Equations, Groundwater movement, Aquifer characteristics.
An integrated finite difference algorithm was presented for numerically solving
the governing equation of saturated-unsaturated flow in deformable porous media.
In recognition that stability of the explicit equation is a local phenomenon, a
mixed explicit-implicit procedure was used for marching in the time domain. In
this scheme, the explicit changes in potential are first computed for all ele-
ments in the system, after which implicit corrections are made only for those
elements for which the stable time step is less than the time step being used.
Time step sizes are controlled automatically in order to optimize the number of
iterations, to control maximum change in potential during a time step, and to
obtain desired outputs. Time derivatives, estimated on the basis of system
behavior during two previous time steps, are used to start the iteration -process
and to evaluate nonlinear coefficients. Boundary conditions and sources can
vary with time or with the dependent variable. Input data are organized into
convenient blocks. Accuracy of solutions can be affected by modeling errors,
different types of truncation errors, and convergence errors. The algorithm
constitutes an efficient tool for analyzing linear and nonlinear fluid flow
problems in multidimensional heterogeneous porous media with complex geometry.
An important limitation is that the model cannot conveniently handle arbitrary
anisotropy and other general tensorial quantities.
78:02F-007
STOCHASTIC ANALYSIS OF SPATIAL VARIABILITY IN SUBSURFACE FLOWS. 1. COMPARISON
OF ONE- AND THREE-DIMENSIONAL FLOWS,
Bakr, A.A., Gelhar, L.W., Gutjahr, A.L., and MacMillan, J.R.
New Mexico Institute of Mining and Technology, Socorro.
Water Resources Research, Vol. 14, No. 2, p 263-271, April, 1978. 4 fig, 23 ref.
Descriptors: *Stochastic processes, *Hydraulic conductivity, *Subsurface flow,
*Aquifers, Groundwater movement, Statistical models, Equations, Hydraulic grad-
ient, Mathematical models, Monte Carlo method.
The complex variation of hydraulic conductivity in natural aquifer materials is
represented in a continuum sense as a spatial stochastic process which is char-
acterized by a covariance function. Assuming statistical homogeneity, the theory
of spectral analysis was used to solve perturbed forms of the stochastic differ-
ential equation describing flow through porous media with randomly varying hy-
draulic conductivity. From analyses of unidirectional mean flows which are
perturbed by one- and three-dimensional variations of the logarithm of the hy-
draulic conductivity, local relationships between the head variance and the log
conductivity variance were obtained. The results showed that the head variance
produced by three-dimensional statistical isotropic conductivity perturbations is
only 5% of that in the corresponding one-dimensional case. The head variance is
also strongly dependent on the correlation distance of the log conductivity
covariance function. These results emphasized the importance of including
spatial correlation structure and multidimensional effects in stochastic simula-
tion of groundwater flow.
* •
78:02F-008
AN EFFICIENT NUMERICAL METHOD OF TWO-DIMENSIONAL STEADY GROUNDWATER PROBLEMS,
Liu, P.L.-F., and Liggett, J.A.
Cornell University, Ithaca, New York, School of Civil and Environmental Engineer-
ing.
Water Resources Research, Vol. 14, No. 3, p 385-390, June, 1978. 6 fig, 2 tab,
11 ref.
Descriptors: *Groundwater movement, *Groundwater, *Model studies, Mathematical
models, Seepage, Dams, Earth dams, Saline water intrusion, Saline water-freshwater
interfaces, Aquifers.
The boundary integral equation method (BIEM) was shown to be an efficient and
accurate numerical technique for solving problems of Darcy flow in porous media.
The BIEM was combined with conformal transformation to the complex potential plane
to solve free surface problems without iteration and with relatively few nodal
18
-------
points. Since the BIEM reduces the effective dimensions of the problem by one,
the computer time varies approximately as the inverse square of the point spacing;
whereas in finite element or finite difference methods; the time varies approxi-
mately as the inverse of the 4th power of the point spacing. Two examples of the
BIEM were presented: flow through an underdrained dam, and a seawater intrusion
problem.
78:02F-009
THEORY OF FLOW IN UNCONFINED AQUIFERS BY INTEGRODIFFERENTIAL EQUATIONS,
Herrera, I., Minzoni, A., and Flores, E.2.
Universidad Nacional Autonoma de Mexico, Mexico City, Centre de Investigaciones
en Matematicas Aplicadas y en Sistemas.
Water Resources Research, Vol. 14, No. 2, p 291-297, April, 1978. 3 fig, 1 tab,
18 ref, 1 append.
Descriptors: *Aguifers, *Drawdown, *Theoretical analysis, *Mathematical models,
Groundwater movement, Unsteady flow, Groundwater, Flow, Compressible flow.
Porous media.
It was shown that when the diffusion of the deviation of the drawdown from its
average value can be neglected, the unsteady flow in unconfined aquifers is
governed by an integrodifferential equation. For incompressible flow, this
equation reduces the Boulton's delayed yield equation with epsilon = 3. When
the flow is compressible, the kernel can be approximated by Boulton's delayed
factor in a range of times whose lower limit approaches zero with the compress-
ibility.
78:02F-010
STEADY PHREATIC FLOW OVER A SLOPING SEMIPERVIOUS LAYER,
Mualem, Y., and Bear, J.
Colorado State University, Fort Collins, Engineering Research Center.
Water Resources Research, Vol. 14, No. 3, p 403-408, June, 1978. 7 fig, 10 ref.
Descriptors: *Groundwater movement, *Groundwater,- *Model studies, Mathematical
models, Boundary layers, Impervious soils, Flow, Steady flow, Slopes, Equations.
This work dealt with steady phreatic flow above a thin semipervious sloping layer
located at some distance below ground surface and above the water table of an
underlying phreatic aquifer. Cases of both upsloping and downsloping semiper-
vious layers were studied. A uniform recharge of constant rate and a semiper-
vious layer of finite length were considered, either with length of flow shorter
than the semipervious layer with flow bypassing its edge. For each case, linear-
ization was applied to the nonlinear continuity equation which governs the flow.
Analytical solutions were derived then for the shape of the phreatic flow wedge,
the length of the wedge, and the discharge rate. These results were compared
with experimental ones obtained in a Hele-Shaw analog.. A good agreement gener-
ally was found between computed and observed results. Because of the analogy
which exists between a phreatic surface and an interface in a coastal aquifer,
the same results also can be applied to the steady freshwater flow above an
interface in an aquifer divided into two subaquifers by a sloping semipervious
layer.
78:02F-011
SENSITIVITY OF OPTIMIZED PARAMETERS IN WATERSHED MODELS,
Mein, R.G., and Brown, B.M.
Monash University, Clayton, Australia, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 2, p 299-303, April, 1978. 1 fig, 2 tab,
12 ref.
Descriptors: *Model studies, *Watersheds (basins), *Simulation analysis, *Meth-
odology, *Hydrologic data, *Boughton model, Analytical techniques, Statistics,
Optimization, Forecasting.
Models which attempt to simulate specifically each of the important hydrologic
components of the watershed response appear to have more potential than black box
models for predicting the effect of. land use change, for application to ungaged
watersheds, and for general studies of the effects of each process on watershed
19
-------
runoff. It has been common practice to evaluate some or all parameters of
watershed models by fitting procedures. A methodology was presented by which
the variance of each fitted parameter of a watershed model can be determined.
This information can be used to determine the degree to which the model para-
meters can be related to physical characteristics. The method was illustrated
by applying the Boughton model to several watersheds and by examining the coef-
ficient of variation of each optimized parameter.
78:02F-012
UNSTEADY FLOW TO A PUMPED WELL IN A FISSURED AQUIFER WITH A FREE SURFACE LEVEL
MAINTAINED CONSTANT,
Boulton, N.S., and Streltsova, T.D.
Sheffield University, England, Department of Civil and Structural Engineering.
Water Resources Research, Vol. 14, No. 3, p 527-532, June, 1978. 6 fig, 2 tab,
6 ref.
Descriptors: *Aquifers, *Puraping, *Drawdown, *Model studies, Mathematical
models, Groundwater, Groundwater movement. Flow, Fissures (geologic), Water
levels, Equations.
New equations were derived for the drawdown in an aquifer consisting of two hori-
zontal layers referred to as the block and the fissure, which have different
hydraulic properties. The free water surface forming the upper aquifer boundary
was located in the block. The water level was assumed to remain constant during
pumping. The block and the fissure were compressible. The depth of the fissure
was small in comparison with that of the block. The abstraction well, lined
along the block, was'pumped at a constant rate. The discharge per unit length
of the unlined part in the fissure was constant, and the radius of the well was
vanishingly small. Type curves for the drawdown in the fissure and the block
were computed and plotted for some selected parameters involved. The effect of
the block compressibility on the drawdown in the fissure was shown by comparing
the type curves with the type A drawdown curves of Boulton. The influence of the
free surface compared with that of an impervious top layer on the drawdown in the
fissure and the block was estimated by comparing the type curves with those of
Boulton and Streltsova found from the equations for a two-layered formation, the
top and bottom surfaces of which were impermeable.
78:02F-013
ANALYSIS OF DYNAMIC AQUIFERS WITH STOCHASTIC FORCING FUNCTION,
Sagar, B.
Department of the Environment, Ottawa, Ontario, Hydrology Research Division; and
Department of the Environment, Ottawa, Ontario, Inland Waters Directorate.
Water Resources Research, Vol. 14, No. 2, p 207-216, April, 1978. 6 fig, 28 ref.
Descriptors: *Saturated flow, *Aquifers, *Mathematical models, *Stochastic pro-
cesses, Model studies, Mathematical studies, Analytical techniques, Analysis,
Flow, Porous media.
The existence of different types of uncertainties in deterministic aquifer
models and the need "of quantitatively accounting for them were discussed. The
case of one-dimensional saturated flow represented by a linear parabolic partial
differential equation with a stochastic forcing function was analyzed. The
dependence of the autocovariance function of the hydraulic head on properties of
the forcing function and nature of the aquifer was brought out.
78:02F-014
A FINITE ELEMENT STUDY OF STEADY STATE FLOW IN AN UNCONFINED AQUIFER RESTING ON
A SLOPING BED,
Choi, E.C.C.
Hong Kong University, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 3, p 391-394, June, 1978. 5 fig, 3 tab,
12 ref.
Descriptors: *Aquifers, *Groundwater movement, *Model studies, Mathematical
models, Finite element analysis, Beds, Boundary layers, Impervious soils, Ground-
water, Seepage, Flow, Slopes, Hydrology, Impermeable beds.
20
-------
A two-dimensional finite element method was used to study the problem of seepage
over a sloping impermeable bed. Flow profile and seepage rates obtained from
the analysis were compared with those solved from Pavlovsky's and Childs1 equa-
tions. The latter equation was found to be more favorable, especially for large
slopes. The effects on the flow profile due to a change in the upstream and
downstream conditions and to a sudden change in the magnitude of the slope to
the impermeable bed also were investigated.
78:02F-015
NUMERICAL SIMULATION OF STEADY STATE THREE-DIMENSIONAL GROUNDWATER FLOW NEAR
LAKES,
Winter, T.C.
Geological Survey, Denver, Colorado, Water Resources Division.
Water Resources Research, Vol. 14, No. 2, p 245-254, April, 1978. 14 fig, 8 ref.
Descriptors: *Groundwater movement, *Lakes, *Seepage, *Surface-groundwater re-
lationships, *Three-dimensional simulation analysis, *Lake-water budget, Model
studies. Numerical analysis, Simulation analysis, Hydrogeology.
Numerical simulation of three-dimensional groundwater flow near lakes shows that
the continuity of the boundary encompassing the local groundwater flow system
associated with a lake is the key to understanding the interaction of a lake with
the groundwater system. The continuity of the boundary can be determined by the
presence of a stagnation zone coinciding with the size of the lake nearest the
downgradient side of the groundwater system. For most settings modeled in this
study the stagnation zone underlies the lakeshore, and it generally follows its
curvature. The length of the stagnation zone is controlled by the geometry of
the lake's drainage basin divide on the side of the lake nearest the downgradient
side of the groundwater system. In the case of lakes that lose water to the
groundwater system, three-dimensional modeling also allows for estimating the
area of lake bed through which outseepage takes place. Analysis of the effects
of size and lateral and vertical distribution of aquifers within the groundwater
system on the outseepage from lakes shows that the position of the center point
of the aquifer relative to the littoral zone on the side of the lake nearest the
downgradient side of the groundwater system is a critical factor. If the center
point is downslope from this part of the littoral zone, the local flow system
boundary tends to be weak or outseepage occurs. If the center point is upslope
from this littoral zone, the stagnation zone tends to be stronger (to have a
higher head in relation to lake level), and outseepage is unlikely to occur.
78:02F-016
NON-STEADY SPHERICAL FLOW TO A CAVITY WELL IN AN INFINITE NONr-LEAKY AQUIFER,
Kanwar, R.S., and Chauhan, H.S.
Iowa State University, Ames, Department of Agricultural Engineering.
Water Resources Bulletin, Vol. 14, No. 3, p 605-612, June, 1978. 1 fig, 10 ref.
Descriptors: *Groundwater, *Groundwater movement, *Water wells, *Model studies,
Mathematical models, Equations, Aquifers, Wells, Drawdown, Hydraulic conductivity.
The non-steady drawdown distribution near a cavity well discharging from an in-
finite non-leaky artesian aquifer was presented. The variation of drawdown with
time and distance caused by a cavity well of constant discharge in a confined
aquifer of uniform thickness and uniform permeability was obtained. The solution
was expressed in a series form which converged rapidly so that only two terms of
the series are needed to obtain an accuracy of more than 95%. A simplified
approach was suggested to find the aquifer characteristics.
78:02F-017
A NOTE ON PACKER, SLUG, AND RECOVERY TESTS IN UNCONFINED AQUIFERS,
Dagan, G.
Tel Aviv University, Ramat-Aviv, Israel, School of Engineering.
Water Resources Research, Vol. 14, No. 5, p 929-934, October, 1978. 3 fig, 1 tab,
4 ref, 45 equ.
Descriptors: Water table aquifers, Hydraulic conductivity, Permeability, Well
data, Steady flow, Numerical analysis.
21
-------
Packer, slug, and recovery tests are common procedures for determining the
hydraulic conductivity of unconfined formations of low permeability. The vol-
umes of water injected or removed from the -borehole are small, so that the water
table remains horizontal and the flow is steady. The flow problem is solved by
source distributions along the well axis. A simple numerical method and numer-
ical results covering a wide range of the parameters of the problem were pre-
sented. The main limitation of the method is the requirement that the active
portion of the well length should be much larger (say, 50 times) than the well
radius.
78:02F-018
STEADY-STATE DRAWDOWNS IN COUPLED AQUIFERS,
Motz, L.H.
Geraghty and Miller, Inc., Tampa, Florida.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
104, No. HY7, Proceedings Paper 13886, p 1061-1074, July,1978. 8 fig, 1 tab,
14 ref.
Descriptors: *Aquifers, *Leakage, *Drawdown, *Mathematical models, Equations,
Groundwater movement, Pumping, Steady flow, Evapotranspiration, Water resources.
The analytical linear solution that predicts the steady-state drawdowns for a
coupled two-aquifer system in which pumping from an underlying artesian aquifer
is balanced by a reduction in evapotranspiration from an overlying water-table
aquifer was developed. An example illustrating how the drawdown equations can
be used to determine whether significant drawdowns will occur in the water-table
aquifer was presented. These drawdown equations can be used for preliminary
analysis and planning studies and to test the convergence of digital model solu-
tions when these more sophisticated techniques are warranted. A major limitation
to using these equations is that the predicted water table drawdowns cannot be
so great that evapotranspiration would cease altogether and, thus, could not be
reduced any further to balance the pumping.
78:02F-019
SOLUTIONS OF BOUSSINESQ'S EQUATION FOR SEEPAGE FLOW,
Gureghian, A.B.
Argonne National Laboratory, Illinois, Division of Environmental Impact Studies.
Water Resources Research, Vol. 14, No. 2, p 231-236, April, 1978. 6 fig, 2 tab,
19 ref.
Descriptors: *Seepage, *Equations, *Groundwater, *Boussinesq's equation, Seepage
control, Ditches, Finite element analysis, Hydrology, Soils, Channels.
Solutions of Boussinesq's equation for groundwater seepage from a ditch with
vertical sides extending in depth to a horizontal impermeable floor were obtained
numerically by using the finite difference and finite element methods for the
case when the seepage rate from the ditch into the soil is constant with time.
Both solutions agreed satisfactorily with experimental results from a Hele-Shaw
analog. It was found, however, that the execution time in the computer for the
finite difference method was an order shorter than that for the finite element
method, and thus the finite difference method is to be preferred. The finite
difference method also was used to obtain a numerical solution for the reverse
situation when water seeps out of the soil into the ditch at a constant rate.
78:02F-020
GROWTH OF GROUNDWATER MOUNDS AFFECTED BY IN-TRANSIT WATER,
Ortiz, N.V., McWhorter, D.B., Sunada, O.K., and Duke, H.R.
Colorado State University, Fort Collins, Engineering Research Center..
Water Resources Research, Vol. 14, No. 6, p 1984-1088, December, 1978. 8 fig,
13 ref..
Descriptors: Groundwater, Water table, Aquifers, Storage capacity, Analytical
techniques, Numerical analysis, Porous media, Water table, Aquifers.
22
-------
An analytical solution accounting for the reduction in storage capacity caused
by intransit water was presented for the growth of groundwater mounds in an un-
confined aquifer in response to uniform deep percolation from a strip of infinite
length but finite width. The solution was obtained by integrating the solution
for the analogous case of heat flow in a composite solid with respect to time.
The aquifer-was considered to be homogeneous, isotropic, and infinite in areal
extent and rested on a horizontal impermeable base. The results from the ana-
lytical solution were compared with those obtained from a numerical model which
was previously verified with data obtained from a physical porous media model.
Dimensionless curves were presented to afford a relatively simple means of ana-
lyzing the growth of groundwater mounds.
78:02F-021
ON THE DETECTION OF SHALLOW AQUIFERS USING THERMAL INFRARED IMAGERY,
Huntley, D.
Connecticut University, Storrs, Department of Geology and Geophysics.
Water Resources Research, Vol. 14, No. 6, p 1075-1083, December, 1978. 11 fig,
21 ref.
Descriptors: Aquifers, Groundwater, Shallow water, Depth, Remote sensing,
Infrared radiation, Radiation, Temperature, Diurnal, Geophysics.
The existence of a tool (the thermal infrared scanner) that primarily records the
spatial variation in surface temperature, combined with a consideration of the
effect of an aquifer on subsurface heat flow patterns, has led several investi-
gators of remote sensing capabilities to look for relations between the distribu-
tion of aquifers and radiometric temperatures. Because of the obvious potential
significance of the ability to detect aquifers remotely, this author investigated
the theoretical and practical basis for aquifer detection. The purpose of this
research was (1) to determine the effect of varying aquifer depth on diurnal sur-
face temperature, (2) to compare the effects produced by varying aquifer depth to
those of varying soil type and soil moisture, and (3) to determine the optimum
interpretive techniques for location of shallow aquifers using thermal infrared
imagery. The results of this investigation led to the following conclusions:
(1) with present technology, it is not practical to estimate groundwater depth
directly using thermal infrared imagery, (2) correlations between groundwater
depth and radiometric temperature noted in the literature are likely caused by
increased evaporative cooling related to increased soil moisture, (3) estimation
of evaporation from thermal infrared imagery acquired during both day and night
may be feasible.
78:02F-022
AN ITERATIVE QUASI-THREE-DIMENSIONAL FINITE ELEMENT MODEL FOR HETEROGENEOUS
MULTIAQUIFER SYSTEMS,
Chorley, D.W., and Frind, E.O.
Waterloo University, Ontario, Canada N2L 3G1.
Water Resources Research, Vol. 14, No. 5, p 943-952, October,' 1978. 11 fig, 2
tab, 27 ref, 25 equ, 1 append.
Descriptors: Groundwater movement, Finite element analysis, Aquifer systems,
Aquitards, Model studies. Mathematical models, Analytical techniques, Economic
justification.
A quasi-three-dimensional flow model was developed for the analysis of hydro-
geologic systems consisting of several aquifers interconnected by aquitards.
Provided only that each layer was continuous within the domain and that a perme-
ability contrast of two orders of magnitude or more existed between adjoining
layers, a system could be completely heterogeneous. Any of the aquifers could be
pumped, and discharge rates could be arbitrary. Flexibility was iterative, solv-
ing aquifers and aquitards separately and providing coupling through the leakage
flux. Aquitard storage and interaction between aquifers were rigorously accounted
for at all times. Convergence was demonstrated experimentally by comparison with
the analytical solution of Neuman and Witherspoon (Publ. 69-1, Dept. of Civil
Eng., Univ. of Calif., Berkeley, 1969). The multiaquifer model was shown to be
much more economical than an equivalent three-dimensional model.
23
-------
78:02F-023
STOCHASTIC ANALYSIS OF SPATIAL VARIABILITY IN SUBSURFACE FLOWS 2. EVALUATION
AND APPLICATION,
Gutjahr, A.L., Gelhar, L.W., Bakr, A.A., and MacMillan, J.R.
New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801.
Water Resources Research, Vol. 14, No. 5, p 953-959, October, 1978. 5 fig, 9
ref, 52 equ.
Descriptors: Subsurface flow, Groundwater movement, Stochastic processes,
Spatial distribution, Porous media, Approximation method, Hydraulic conductivity,
Network design, Aquitards.
The stochastic differential equation describing one-dimensional flow in a sta-
tistically homogeneous porous medium was solved exactly, and the results were
compared with an approximate solution considering small perturbations in the
logarithm of the hydraulic conductivity. The results showed that the logarithmic
approximation is valid when the standard deviation of the natural logarithm of
the hydraulic conductivity, sigma sub f, is less than 1; the errors increase
rapidly for sigma sub f > 1. The effective hydraulic conductivity of statis-
tically homogeneous media with one-, two- and three-dimensional perturbations was
determined to the first order in the square of sigma sub f (SSF). The effective
conductivity was found'to be the harmonic mean for one-dimensional flow, the
geometric mean for two-dimensional flow, and (1 + SSF/6) times the geometric
mean for three-dimensional flow. The application of stochastic analysis was
illustrated through two elementary network design problems that demonstrate the
importance of the correlation length of the hydraulic conductivity and the role
of measurement error.
78:02F-024
THE COMPUTATIONAL EFFICIENCY AND TAYLOR EXPANSION DERIVATION OF APPROXIMATING
EQUATIONS TO THE GROUNDWATER FLOW EQUATION,
Kuiper, L.K.
Ahmadu Bello University, Zaria, Nigeria, Department of Physics.
Water Resources Research, Vol. 14, No. 6, p 1171-1181, December, 1978. 8 fig, 2
tab, 12 ref, 52 equ.
Descriptors: Groundwater movement. Approximation method, Finite element analysis,
Numerical analysis, Mathematical studies, Groundwater.
In this paper, the relative accuracy and speed of 12 different approximations for
the solution of the homogeneous one-dimensional groundwater flow equation were
compared. Two of these approximations were derived by the use of finite elements
including both the time and the spacial domain, others by the use of finite ele-
ments in the spacial domain and finite differences in the time domain, and the
remainder by the use of finite differences in both the time and the spacial
domain. Several generalizations of these approximations for use with the non-
homogeneous one-dimensional groundwater flow equation were also compared for
accuracy. A general procedure for the derivation of approximations to differen-
tial equations was presented.
78:02F-025
GALERKIN FINITE ELEMENT PROCEDURE FOR ANALYZING FLOW THROUGH RANDOM MEDIA,
Sagar, B.
Punjab Agricultural University, Ludhiana 141004, India, Department of Civil
Engineering.
Water Resources Research, Vol. 14, No. 6, p 1035-1044, December, 1978. 3 fig, 2
tab, 19 ref, 28 equ.
Descriptors: Groundwater movement, Flow around objects, Porous media/ Stochastic
processes, Finite element analysis, Mathematical studies, Statistical methods.
A method was presented for analyzing flow through a porous medium whose parameters
are random functions. Such a medium was conceptualized as an ensemble of media
with an associated probability mass function. The flow problem in each member of
this ensemble is deterministic in the usual sense. All the solutions belong to a
particular Hilbert space, and hence they can be written in terms of linear com-
binations of its basis functions. This is similar to the Galerkin formulation
24
-------
except that the coefficients in the linear combination are no longer deterministic
quantities but random functions. The finite element method in conjunction with
a Taylor series expansion was used to get the first two moments of the solution
approximately. The method does not require specification of full probability
mass functions of the parameters but only their first two moments, and spatial
correlations can be easily accounted for. However, it was assumed that the
probability mass functions are peaked at the expected value and are smooth in its
vicinity. A sample problem was solved to illustrate the procedure. It was
observed that the result is sensitive to the element size in the numerical scheme
and the variances and spatial correlations of parameters. The expected value
of the hydraulic head was found to differ significantly from the results that would
have been obtained if the problem had been solved deterministically.
78:02F-026
THE CARBON ISOTOPE GEOCHEMISTRY OF A SMALL GROUNDWATER SYSTEM IN NORTHEASTERN
ONTARIO,
Fritz, P., Reardon, E.J., Barker, J., Brown, R.M., and Cherry, J.A.
Waterloo University, Waterloo, Ontario, Canada, Department of Earth Sciences.
Water Resources Research, Vol. 14, No. 6, p 1059-1067, December, 1978. 5 fig,
5 tab, 23 ref.
Descriptors: Isotope studies, Carbon, Geochemistry, Carbon dioxide, Carbonate
rocks, Groundwater, Crystalline rocks, Isotope fractionation, Canada.
The carbon isotopic composition (13C and 14C) of the inorganic carbon dissolved in
the waters of a small, largely unconfined aquifer in unconsolidated sediments on
the Canadian Shield was investigated. Three principal carbon sources were
recognized: soil C02, rock carbonate, and biogenic C02. The average delta-13C
value of the soil C02 was close to -21.0 ± 1.5, and present-day 14C activities
of the soil C02 varied between 130 and 162% modern 14C. Very minor amounts (<1.0%)
of carbonate minerals were present within the aquifer and reacted with this soil
C02 to produce a dissolved inorganic carbon (DIG) with 14C activities which were
as much as 50% below the initial activities of the soil CO2. The third carbon
source, a biogenic C02, could be detected only indirectly, and its presence was
primarily deduced from the occurrence of methane in the deeper parts of these
aquifers. The large isotope fractionation which occurred during bacterial co-
production of CO2 with this methane resulted, however, in a 13C-rich CO2 and thus
a DIC with high delta-13C values. Since the origin of the destroyed organic
matter was not known, no assessment of the importance of this CO2 for the 14C
contents of the DIC was possible.
78:02F-027
DELAYED AQUIFER YIELD AS A PHENOMENON OF DELAYED AIR ENTRY,
Bouwer, H., and Rice, R.C.
United States Water Conservation Laboratory, Science and Education Administration,
United States Department of Agriculture, Phoenix, Arizona 85040.
Water Resources Research, Vol. 14, No. 6, p 1068-1074, December, 1978. 8 fig,
10 ref, 6 equ.
Descriptors: Water table aquifers, Aquifer testing, Vadose water, Air entrainment,
Pore water, Drawdown, Specific yield, Pumping, Groundwater, Laboratory tests.
Delayed release of pore water from a pumped, unconfined aquifer is treated as a
situation of restricted air movement in the vadose zone due to layers of high
water content. This restricted movement produces below-atmospheric pressures in
the pore air above the water table, which cause the water table initially to drop
faster than the dewatered zone. The initial yield thus is less than the full
specific yield, which develops after a certain water table drop. Equations were
derived that relate delayed yield to air entry value and height above water table
of saturated layers in the vadose zone. These equations agreed with results from
a delayed yield experiment on a vertical soil column and produced ratios between
initial and final yield that resembled those calculated by others from actual
pumping tests. An axisymmetric flow system, simulated by interconnected jars with
narrow standpipes, produced delayed yield drawdown curves that were amendable
to Boulton's analysis.
25
-------
78:02P-028
SUBSURFACE DRAINAGE IN SOILS WITH HIGH HYDRAULIC CONDUCTIVITY LAYERS,
Tang, Y.K., and Skaggs, R.W.
North Carolina State University, Raleigh, Department of Biological and Agricultural
Engineering.
Transactions of the American Society of Agricultural Engineers, Vol. 21, No, 3,
p 515-521, May-June, 1978. 16 fig, 20 ref.
Descriptors: *Subsurface drains, *Hydraulic conductivity, *Soils, Groundwater
movement, Water table aquifers, Drains, Mathematical models, Equations, Head loss,
Saturated flow, Computer models.
The Richards equation for two-dimensional, saturated-unsaturated flow during
drainage was solved for layered soils using finite difference methods. -Solutions
were obtained for soils in which the deeper layer has a higher hydraulic con-
ductivity than the surface layer. Solutions were presented to show the distribu-
tion of equipotential lines and position of the water table during drainage pro-
cesses. When the drain depth is increased so that it is closer to the high con-
ductivity layer, head loss due to convergence near the drain is reduced. Thus,
deeper drains may significantly increase drainage rates, even if the hydraulic
head at the outlet remains unchanged. This effect is larger for deep profiles
and narrow drain spacings than for shallow profiles and wide spacings. The
effect of increasing the drain depth also increases with the hydraulic conductivity
of the bottom layer. When outlet conditions are limiting, the most efficient
drain depth is that of the layer interface. Solutions for various cases showed
that further increasing the depth had only a slight effect on water table drawdown.
26
-------
SECTION VII
WATER CYCLE
WATER IN SOILS (GROUP 02G)
78:02G-001
NUMERICAL STUDY OF QUASI-ANALYTIC AND FINITE DIFFERENCE SOLUTIONS OF THE SOIL-
WATER TRANSFER EQUATION,
Hayhoe, H.N.
Department of Agriculture, Ottawa, Ontario, Canada.
Soil Science, Vol. 125, No. 2, p 68-74, February, 1978. 3 fig, 3 tab, 9 ref.
Descriptors: *Infiltration, *Soil water movement, *Wetting, *Model studies,
Soil water, Moisture content, Mathematical models, Analytical techniques,
Equations, Soil science.
The special case of horizontal infiltration of water into a dry soil was
utilized to study the problem of using standard finite differencing with an
economic grid refinement to locate the wetting front accurately. The procedure
used to determine an average value on grid subintervals for the strongly
concentration-dependent soil-water diffusivity was identified as being a criti-
cal factor in accurately approximating the moisture profile. New averaging
techniques were proposed which were shown to locate the steep front with sig-
nificantly more accuracy. The exact solution was required as a basis for this
study. To meet this need, a quasi-analytic technique was introduced and shown
to be effective through numerical experiments and comparison with an alternative
scheme.
78:02G-002
BOUNDARY CONDITIONS IN MODELING WATER FLOW IN UNSATURATED SOILS,
Zaradny, H.
Polish Academy of Sciences, Gdansk. Institute of Hydraulic Research.
Soil Science, Vol. 125, No. 2, p 75-82, February, 1978. 11 fig, 20 ref.
Descriptors: *Soils, *Model studies, *Soil water movement, *Unsaturated soils,
Flow, Mathematical models, Moisture content, Sands, Boundaries (property),
Equations.
Simultaneous physical and mathematical modeling was employed to prove that the
Richards equation holds true for problems of water flow in unsaturated sand
soils. This was shown through good agreement between computation results and
data obtained from a physical model. Fine sand was used in the model, and
changes in the water content were measured with Am 241. Good results were
obtained upon assuming the boundary condition along the supply line to be in the
form of the x-derivative of water content. It also was found that the widely
accepted boundary condition, namely that water content is constant at the supply
boundary, can bring about erroneous conclusions. Good efficiency was achieved
in the computations upon the assumption of a time variable increment which can
be determined with a criterion derived through numerical experiments.
78:02G-003
THE USE OF DYNAMIC SOIL WATER CHARACTERISTICS IN A NUMERICAL DESORPTION MODEL,
Watson, K.K., and Whisler, F.D.
Mississippi Agricultural and Forestry Experiment Station, Mississippi State.
Soil'Science, Vol. 125, No. 2, p 83-91, February, 1978. 6 fig, 11 ref.
Descriptors: *Soil water, *Pressure head, *Soil water movement, *Model studies,
Soils, Mathematical models, Water table, Drainage, Desorption, Hysteresis.
27
-------
A numerical solution of the gravity drainage to a water table of an initially
saturated column of porous material was used to examine the results of experi-
mental studies where the volumetric water content (theta) during desorption was
found to be dependent on both the soil water pressure head (h) and the rate of
change of h with time (dh/dt). In keeping with the experimental findings, the
h(theta) relationship was made space-dependent, and the water content and soil
water pressure head profiles for this case were compared with the results ob-
tained for two analyses in which the h(theta) relationship was held constant
during drainage. These comparisons indicated that the water content profile
is generally an insensitive measure of h(theta) variations. The relationship
between h and dh/dt for specified theta values was determined from the space-
dependent h(theta) analysis and compared with the shape of the curves reported
in the experimental studies.
78:02G-004
THEORETICAL MODELING OF MIXED-ELECTROLYTE SOLUTION FLOWS FOR UNSATURATED SOILS,
Bresler, E.
Agricultural Research Organization, Bet Dagan, Israel, Division of Soil
Physics.
Soil Science, Vol. 125, No. 4, p 196-203, April, 1978. 20 ref.
Descriptors: *Mathematical models, *Unsaturated flow, *Salts, *Soils,
Theoretical analysis, Equations, Calcium, Sodium, Convection, Diffusion.
A mixed salt solution with ions that interact with the soil matrix are important
in field problems involving the simultaneous flow of water and mixed Na-Ca salts
in unsaturated soils. Governing partial differential equations describing tran-
sient, one-dimensional, simultaneous transfer of mixed anions, cations, and
water were formulated, taking into account physicochemical interaction between
mono and divalent ions and the soil matrix. Effects of convection, diffusion,
mechanical dispersion, anion exclusion, cation exchange and adsorption, and
coupling phenomena were considered jointly. Soil-interacting and coupling para-
meters were estimated theoretically from mixed-ion diffuse double-layer theory,
taking into account tactoids, capillarity, and hydrodynamic considerations. The
coupling-interacting parameters included: osmotic efficiency coefficient, anion
exclusion, cation exchange equilibria, soil water retentivity, 'and unsaturated
hydraulic conductivity and their dependence on soil water content and soil
solution concentration and composition. A finite difference approach that
eliminates numerical dispersion was used to approximate the nonlinear partial
differential equations and the boundary conditions appropriate to infiltration,
redistribution, drainage, and evaporation of soil water. A brief computational
scheme concluded the paper.
78:02G-005
A SOIL COLUMN TENSION LYSIMETER THAT MINIMIZES EXPERIMENTAL EDGE EFFECTS,
Cronan, C.S.
Dartmouth College, Hanover, New Hampshire, Department of Biological Sciences.
Soil Science, Vol. 125, No. 5, p'306-309, May, 1978. 2 fig, 2 tab, 12 ref.
Descriptors: *Lys±meters, *Leachate, *Soil chemistry, "Infiltration, *Perco-
lation, *Tension lysimeter, *Edge effects, Instrumentation, Infiltrometers,
Runoff.
A new tension lysimeter, intended for use with isolated, undisturbed soil'
columns, has been developed. This lysimeter offers the following advantages:
it is inexpensive; it minimizes problems associated with experimental edge
effects; it is essentially chemically inert; and it permits sampling both
saturated and unsaturated flow in soil leaching experiments. Data were pre-
sented to illustrate the relatively low variability observed in flow .volumes
and leachate chemistry between replicate undisturbed soil columns receiving
identical treatments.
78:02G-006
SOLUTE TRANSPORT THROUGH SOIL WITH NONUNIFORM WATER CONTENT,
DeSmedt, F., and Wierenga, P.J.
28
-------
New Mexico State University, University Park, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 1, p 7-10, January-
February, 1978. 4 fig, 16 ref.
Descriptors: *Solutes, *Soil water movement, *Moisture content, *Model studies,
Mathematical models, Theoretical analysis. Analytical techniques, Equations,
Soil water, Leachate.
An approximate analytical solution was presented for steady flow of salt through
soil with a nonuniform distribution of the water content. The solution was in
good agreement with a numerical computer solution provided by the CSMP simula-
tion language. Both solutions also agreed with the analytical solution for
soils with a uniform distribution of the water content. It was shown that
effluent curves from soil profiles, with the same average water content and
leached at the same steady rate, are basically the same and thus independent of
the variation of the water content in such profiles.
78:020-007
TRANSIENT-AND STEADY-FLOW EXPERIMENTS TESTING THEORY OF WATER FLOW IN SATURATED
BENTHONITE,
Smiles, D.E.
Commonwealth Scientific and Industrial Research Organization, Canberra City,
Australia, Division of Environmental Mechanics.
Soil Science Society of America Journal, Vol. 42, No. 1, p 11-14, January-
February, 1978. 5 fig, 1 tab, 12 ref.
Descriptors: *Soil water movement, *Flow, *Model studies, Mathematical models,
Laboratory tests, Stratified flow. Steady flow, Unsteady flow, Darcy's law,
Clays.
The theory of water flow in a saturated, swelling clay has been criticized
recently. This criticism concerns possible effects on the material character-
istics of particle re-orientation during transient flow, as well as suggestions
that the flux equation (Darcy's law) may be inappropriate to such systems. This
paper examined these problems by comparing data from transient-and steady-flow
experiments with bentonite. The data from all experiments are mutually con-
sistent within the experimental error. It was concluded that Darcy's law is
valid for this material and that the conductivity/water content, and water
content/suction relationships are well defined.
78:020-008
DISPERSION IN SOIL COLUMNS: EFFECT OF BOUNDARY CONDITIONS AND IRREVERSIBLE
REACTIONS,
Parlange, J.-Y., and Starr, J.L.
Connecticut Agricultural Experiment Station, New Haven.
Soil Science Society of America Journal, VoL 42, No. 1, p 15-18, January-
February, 1978. 4 fig, 17 ref.
Descriptors: 'Dispersion, *Soils, *Model studies, 'Mathematical models, Adsorp-
tion, Convection, Diffusion, Soil water, Solutes, Aqueous solutions.
A closed form approximate analytical solution was provided which describes the
transport of a solute in a soil column. The effects of convection, dispersion,
and adsorption were included. The latter can include both linear adsorption and
first-or zero-order reactions. The effect of the finite length of a soil column
on the miscible displacement of the solute was discussed in detail. It was
shown in particular that the standard solution used in the past is accurate to
describe the breakthrough curve but not the profile within the column.
78:020-009
STEADY-STATE SOLUTE CONVECTION IN TWO DIMENSIONS WITH NONUNIFORM INFILTRATION,
Batu, V., and Gardner, W.R.
Wisconsin University, Madison, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 1, p 18-22, January-
February, 1978. 6 fig, 16 ref.
29
-------
Descriptors: *Solute, *Percolation, *Infiltration, *Model studies, Mathematical
models. Soil water, Soil water movement. Flow, Unsaturated flow, Non-uniform
flow.
The steady-state unsaturated flow equation in two dimensions was solved for an
exponential unsaturated conductivity using the Kirchhoff transformation.
Streamlines, travel times, and isochrones were calculated for an infiltration
rate which is a piece-wise linear function of horizontal coordinate. Results
were compared with the equivalent solutions for a saturated soil. In addition
to solutions in dimensionless form, an example was presented for Plainfield
sand. The results confirmed that surface variations in infiltration rate may
be propagated to a considerable depth, particularly in sandy soils. This may
account, in part, for the variability in solute leaching frequently observed in
the field.
78:02G-010
EFFECTS OF CLAY TYPE AND CONTENT, EXCHANGEABLE SODIUM PERCENTAGE, AND ELECTRO-
LYTE CONCENTRATION ON CLAY DISPERSION AND SOIL HYDRAULIC CONDUCTIVITY,
Frenkel, H., Goertzen, J.O., and Roades, J.D.
Agricultural Research Service, Riverside, California, Salinity Lab.
Soil Science Society of America Journal, Vol. 42, No. 1, p 32-39, January-
February, 1978. 9 fig, 2 tab, 31 ref.
Descriptors: *Hydraulic conductivity, *Electrical conductance, *Soils, *Clays,
Laboratory tests, Soil water movement, Soil water, Alkaline soils, Leachate,
Salts.
The hydraulic conductivities and gradients along soil columns packed with mont-
morillonitic, vermiculitic, and kaolinitic soils adjusted to different levels of
exchangeable sodium were determined at different salt concentrations. The data
showed that plugging, of pores by dispersed clay particles is a major cause of
reduced soil hydraulic conductivity for surface soils irrigated with sodic
waters.
78:02G-011
MULTIPLE TENSIOMETER FLUSHING SYSTEM,
Huber, M.J., and Dirksen, C.
Agricultural Research Service, Riverside, California, Salinity Lab.
Soil Science Society of America Journal, Vol. 42, No. 1, p 168-170, January-
February, 1978. 1 fig, 5 ref.
Descriptors: *Tensiometers, *Soil water, *Instrumentation, Equipment, Valves,
Air, Bubbles, Irrigation, Soil science, Flushing.
A system for simultaneous flushing of a large number of tensiometers was
described. It includes a multiple shutoff valve and a manometer with movable
bottom. Flushing procedures were described; they are fast and simple. It can
be used with any direction of installation of tensiometers or tubing, for in-
stance, when all tubing is kept below the soil surface to reduce temperature
fluctuations. A concentric tubing arrangement reduces air diffusion into the
measuring tubing. The system offers potential for improved data quality and
reduced need for flushing.
78:026-012
HYDRODYNAMIC DISPERSION DURING ABSORPTION OF WATER BY SOIL,
Smiles, D.E., Philip, J.R., Knight, J.H., and Elrick, D.E.
Commonwealth Scientific and Industrial Research Organization, Canberra,
Australia, Division of Environmental Mechanics.
Descriptors: *Dispersion, *Soil water movement, *Solutes, *Absorption, Labora-
tory tests, Leaching, Unsteady flow, Unsaturated flow, Soil water, Salts.
An experimental study is reported of hydrodynamic dispersion of low concentra-
tion solutions during absorption into horizontal columns of soil with initially
uniform moisture and solute contents. The initial soil solutions were of rela-
tively high salt concentration. It was found that both the water and salt
30
-------
concentration profiles preserved similarity in terms of distance divided by the
square root of time. This observation implies that the longitudinal dispersion
coefficient is insensitive to pore water velocity and may be taken as a function
of the volumetric water content only, at least for a given initial (low) mois-
ture content. The formulation which follows is frankly phenomenological. It
provides a simple means of predicting dispersion during flow in unsaturated soils
which promises to be sufficiently accurate for most purposes.
78:02G-013
PERINENT CRITERIA FOR DESCRIBING THE DISSOLUTION OF GYPSUM BEDS IN FLOWING WATER,
Keisling, T.C., Rao, P.S.C., and Jessup, R.E.
Goergia Coastal Plain Experimental Station, Tifton, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 2, p 234-236, March-April,
1978. 1 fig, 4 ref.
Descriptors: *Gypsum, *Dissolved solids, *Mass transfer, *Dissolution, Model
studies, Mathematical models, Solutes, Flow, Dispersion, Erosion.
The equation for convective-dispersive solute transport in porous beds and the
continuity equation were used to derive a relationship describing the dissolu-
tion of gypsum beds in flowing water. The parameters involved in the derived
relationship were: bed length, solution flow velocity, dispersion coefficient,
mass transfer rate coefficient, and gypsum fragment size. The proposed rela-
tionship was compared with previously published data and shown to be valid. A
potential practical field application of the procedure was presented.
78:02G-014
CALIBRATION STABILITY AND RESPONSE TIME FOR SALINITY SENSORS,
Wood, J.D.
Agricultural Research Service, Riverside, California, Salinity Laboratory.
Soil Science Society of America Journal, Vol. 42, No. 2, p 248-250, March-April,
1978. 1 fig, 4 tab, 14 ref.
Descriptors: Instrumentation, *Salinity, *Saline, soils, Calibrations, Equipment,
Laboratory tests,' Stability, Electrical conductance, Measurement, Soil science.
Commercially produced salinity sensors removed from field and lysimeter experiments
lasting from three to five years were tested for calibration stability relative to
the original factory calibration. Significant changes in calibration occurred in
up to 14% of the sensors after four and five years of use. Response to a step-
change in salinity also was examined for commercial units in a field installation.
Calculated response factors were lower than those found in a previous laboratory
experiment. However, response was sufficiently rapid to assure accurate readings
if changes in salinity occur in time intervals exceeding five days.
78:02G-015
APPROXIMATE ANALYTICAL SOLUTION FOR SOLUTE FLOW DURING INFILTRATION AND REDISTRIBUTION,
De Smedt, P., and Wierenga, P.J.
New Mexico State University, Las Cruces, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 3, p 407-411, May-June,
1978. 5 fig, 3 ref, 20 equ.
Descriptors: Analytical techniques, Dispersion, Soil water movement, Solutes,
Infiltration, Simulation analysis, Hydrodynamics, Unsaturated flow, Numerical analysis.
An approximate analytical solution is developed to describe solute flow in soil
during infiltration and redistribution. For the solution it is assumed that
hydrodynamic dispersion is linearly related to the pore water velocity. In
order>to use the solution it is necessary to estimate the solute penetration
depth. Methods of estimating the solute penetration depth are discussed.
Solute concentration distributions computed with the approximate analytical
solution are compared with those obtained with a numerical model. It is shown
that the solution proposed is most useful during the infiltration phase. Dur-
ing the redistribution phase the approximate analytical solution provides a
31
-------
first-order estimate of the solute distribution with time and depth. Computed
chloride distributions compare favorably with chloride concentrations observed
by Warrick et al. (1971).
78:02G-016
SOIL WATER FLOW MODEL WITH TWO-DIMENSIONAL AUTOMATIC GAMMA RAY ATTENUATION
SCANNER,
Dirksen, C., and Huber, M.J.
Science and Education Administration, Riverside, California, Salinity Laboratory.
Water Resources Research, Vol. 14, No. 4, p 611-614, August, 1978. 2 fig, 17
ref.
Descriptors: *Soil water movement, *Moisture content, laboratory tests,
*Instrumentation, Model studies, Soil water, Gamma rays, Moisture meters, Soil
moisture meters, Automation.
Described is a physical laboratory model to study two-dimensional transient
water and solute transport in unsaturated soil, including water uptake by roots.
It features an automatic two-dimensional gamma ray attenuation scanner for mea-
suring soil water content. Automation is obtained with a simple closed loop
control circuit. After a gamma count is transmitted to the teletypewriter, a
signal is sent to the hydraulically moved scanner to search for the next grid
point. Upon arrival, the scanner sends a signal back to initiate another data
acquisition sequence, and so on. In this way, synchronization between counter
and scanner is assured independent of counting time, travel time, configuration
of grid points, temporary slowdown, etc. It also eliminates dead time between
grid points for any recording pattern. Grid points are established by an array
of holes that trap the core of a solenoid actuator. The configuration of grid
points can be changed easily by opening and closing the desired holes. This
mechanical trapping was found to be simpler and more accurate than a potentio-
metric control. The soil water flow model is constructed in modules. It can be
used as one unit of 3.15 by 1.07 by 0.178 m and inclined up to 30 degrees, or it
can be subdivided into up to eight compartments, each with its own drainage
filter tubes. The front glass walls allow visual.observations of soil packing,
wetting fronts, root distribution, etc. The back aluminum walls allow installa-
tion of instruments, such as tensiometers, salinity sensors, and psychrometers.
78:026-017
LINEARIZED MOISTURE FLOW WITH LOSS AT THE SOIL SURFACE,
Lomen, D.O., and Warrick, A.W.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Journal, Vol. 42, No. 3, p 396-399, May-June,
1978. 2 fig, 8 ref, 12 equ,
Descriptors: Soil water movement, Unsaturated flow, Evaporation.
The general solution of a linearized moisture flow equation is derived for point
and line sources whether buried or on the soil surface. The surface flux is
taken to be proportional to the matric flux potential, which is consistent with
the physical situation of small evaporative losses for dry soil and larger
losses for wet soil. The fraction of water lost at the surface turns out to be
identical for point and line sources and for the steady-state case is (m/(2+m))
exponent (-alpha d) where m is the surface flux proportionality constant, d the
depth of source, and alpha a constant from the assumed unsaturated hydraulic
conductivity function. This fraction is plotted as a function of time for a
fixed source depth. Also given are curves depicting the total water loss as a
function of source depth. A generalized solution is derived for any type of
source located in a horizontal plane.
78:02G-018
HYDRAULIC CONDUCTIVITY OF SOILS: UNIFIED APPROACH TO THE STATISTICAL MODELS,
Mualem, Y., and Dagan, G.
Colorado State University, Fort Collins, Department of Civil Engineering.
Soil Science Society of America Journal, Vol. 42, No. 3, p 392-395, May-June,
1978. 12 ref.
32
-------
Descriptors: *Hydraulic conductivity, *Soils, *Statistical models, Unsaturated
flow, Porous media, Soil moisture. Pore pressure, Equations, Mathematical
models, Darcy's law.
Conceptual theory of the hydraulic conductivity of unsaturated porous media was
presented. This analysis permits the systematic derivation of the models of
E.G. Childs and N. Collis George, M.R.J. Wyllie and G.H.F. Gardner, and Y.
Mualem, as well as other existing and new versions, from common statistical
principles. The resulting formulas of unsaturated hydraulic conductivity can be
classified into three categories: (1) universal formulas independent of the soil
type which result from extremely simplifying assumption; (2) formulas with one
degree of freedom, and (3) formulas with two degrees of freedom. The latter two
types of equations result from accounting for the correlation between pores and
the tortuosity of flow path. These formulas can be adjusted to soil type to
represent better the variability of soil properties and to increase the accuracy
of the predicted hydraulic conductivity. However, in this stage it is a poten-
tial advantage only. Empirical study should be followed in order to derive the
optimal methods of estimating the unknown parameters.
78:02G-019
LEACHING CHARACTERISTICS OF A LAYERED FIELD SOIL,
Starr, J.L., DeRoo, B.C., Frink, C.R., and Parlange, J.Y.
Connecticut Agricultural Experiment Station, New Haven.
Soil Science Society of America Journal, Vol. 42, No. 3, p 386-391, May-June,
1978. 8 fig, 18 ref.
Descriptors: *Groundwater movement, *Percolating water, *Soil physical proper-
ties, Infiltration,.Soil chemistry. Leaching, Solutes, Soil water movement,
Saturated flow.
Two ponded flow experiments were conducted to study the leaching characteristics
of a layered field soil, fine sandy loam over coarse sand, with a water table at
a depth of 1.8 m. In the first experiment, a steel cylinder 1.8 m in diameter
was driven into a soil to a depth of 3.6 m. Infiltrations of water and dye pro-
vided the means for direct observation of the effect of air entrapment upon the
rates of infiltration as well as the primary pattern of water flow through the
coarse subsoil. The rate of infiltration was observed to increase by nearly two-
fold when the entrapped air between the saturated surface layer and the shallow
groundwater table was vented directly to the atmosphere. Removal of the soil
layers following infiltration of a dye solution showed that most of the infil-
trating water moved through fingers ranging from 5 to 20 cm in diameter. . In the
second experiment, chloride distributions at six depths were measured following
the application of a pulse of 0.3N CaC12 solution to the soil surface. Chloride
movement for the 20- to 60-cm soil depths averaged about 50% slower than that
determined from the average pore-water velocity at the soil surface. In contrast
to this relatively low rate of chloride movement, several salt pulses reached the
120- and 180-cm depths soon after or before reaching the 60-cm depth. This
greatly increased flow rate corresponds to the observations in the first experi-
ment where flow became unstable and the solute moved in fingers of flow below tine
60-cm depth.
78:02G-020
AN ANALYSIS OF SENSIBLE AND LATENT HEAT FLOW IN A PARTIALLY FROZEN UNSATURATED
SOIL,
Fuchs, M., Campbell, G.S., and Papendick, R.I.
Washington State University, Pullman, Department of Agronomy and Soils.
Soil Science Society of America Journal, Vol. 42, No. 3, p 379-385, May-June,
1978. 5 fig, 2 tab, 15 ref, 36 equ, 2 append.
Descriptors: Frozen soils, Heat flow, Freezing, Thawing, Solutes, Latent heat,
Thermal conductivity. ,
A heat flow theory has been developed which can be used to predict freezing and
thawing cycles of a temperate soil. The latent heat of fusion is incorporated
into the classical heat flow equation with the heat capacity and the thermal
33
-------
conductivity of the soil modified to include terms which account for the phase
transformation. Computations for a Palouse silt loam soil show that the ice-
liquid phase transformation occurs over a defined temperature range where the
apparent heat capacity and the apparent thermal conductivity may take on values
which are several orders of magnitude larger than those either in the unfrozen
or in the near completely frozen soil. The computations also indicate that
the presence of solutes in the soil water significantly lowers the temperature
range over which the freeze-thaw zone develops and may allow considerable
transport of water and heat at lower temperature than in the absence of solutes.
78:020-021
A METHOD OF PROMOTING PENETEATION OF WATER INTO TIGHT, SLOPING SOIL UNDER DRIP
IRRIGATION,
Hillel, D.
University of Massachusetts, Amherst, Department of Plant and Soil Science.
Soil Science, Vol. 125, No. 5, p 329-330, May, 1978. 1 fig.
Descriptors: Irrigation, Infiltration, Penetration, Runoff, Evaporation, Root
zone. Gravels, Methodology.
A method is proposed to increase penetration of water into the root zone, as
well as to reduce runoff and evaporation by means of gravel-filled pits under
each emitter when drip irrigation is applied to sloping ground of low infil-
trability. A sample calculation is provided to help determine the optimal
dimensions of the gravel pits.
78:02G-022
FRONTAL MOVEMENT OF AQUEOUS SOLUTIONS DURING REDISTRIBUTION THROUGH AIR-DRY SAND
COLUMNS AS A FUNCTION OF COLUMN LENGTH AND TIME,
Routson, R.C., and Brown, D.J.
Battelle Pacific Northwest Laboratories, Richland, Washington.
Soil Science, Vol. 125, No. 5, p 320-325, May, 1978. 5 fig, 3 tab, 19 ref.
Descriptors: *Aqueous solutions, *Sands, *Laboratory tests, *Soil water move-
ment, Sorption, Soils, Depth, Graphical analysis, Equations, Wetting.
The frontal movement during redistribution of unsorbed waste fronts through an
air-dried sand was measured as a function of time and column length for columns
25-200 cm long. All column data fit an equation of the form S = Ex T to the F
power. S was found to be significantly correlated with T (at the 1% level).
The equation was normalized by dividing S and E by the column length. When this
was done, data for all columns fit a single normalized equation. Use of this
equation allows estimation of the shortest possible time necessary for the front
of a pulse of waste solution to reach a given depth in a homogeneous soil
system.
78:02G-023
EXCHANGEABLE SODIUM AND SOIL WATER BEHAVIOR UNDER FIELD CONDITIONS,
Acharya, C.L., and «Abrol, I.P.
Central Soil Salinity Research Institute, Karnal, India.
Soil Science, Vol. 125, No. 5, p 310-319, May, 1978. 9 fig, 1 tab, 15 ref.
Descriptors: *Sodium, *Soil management, *Alkaline soils, "Irrigation water,
*Soil chemical properties, Infiltration, Permeability, Soil analysis, Leaching,
Land reclamation.
The effect of exchangeable sodium on soil water behavior under field conditions
was investigated in five differentially gypsum treated plots of a highly sodic
soil. The soil is representative of the sodic soils of the Indo-gangetic plains
in northern India. The soil texture is sandy loam in the surface 0-15 cm, and
the clay fraction is dominantly illitic. Exchangeable sodium percentage (ESP)
varied from 4 to 38 in 0-15 cm, and 28 to 88 in the 15-30 cm layer. Basic in-
take rate of the soil increased from 8.7 mm per day in soil of highest ESP to
about 25 mm per day in soil of lowest ESP. Higher basic intake rate and in-
creased retention at low suctions resulted in greater profile water storage.
34
-------
Soil water diffusivity values (D) calculated from the water distribution
following evaporation showed that at a water content of 0.22 cu cm/cu while D
(sq cm/day) decreased from 34 to 26 when ES.P increased from 4 to 11, the D value
sharply decreased to 8 with a further rise in ESP to 16. Improvement in trans-
mission characteristics resulting from lowered ESP was reflected in the drying
pattern of soils. The first stage of drying was delayed in low ESP treatments
compared to the high ESP treatment because of regular movement of water from
lower layers to the surface to meet the evaporation demand. The effect of
treatments on water movement was noticeable to a depth of 90 cm studies in these
experiments, although the improvement in layers below 15 cm was very small in
treatments receiving lower doses in gypsum.
78:02G-024
COMPACTION EFFECTS ON THE HYDRAULIC CONDUCTIVITY OF A CLAY SOIL,
Douglas, E., and McKyes, E.
Macdonald College, Ste. Anne de Bellevue, Quebec, Canada, Department of
Agricultural Engineering.
Soil Science, Vol. 125, No. 5, p 278-282, May, 1978. 6 fig, 7 ref.
Descriptors: *Compaction, *Compacted soils, *Hydraulic conductivity, *Clays,
Unsaturated flow, Laboratory tests, Equations, Saturated soils, Porosity,
Pressure.
Unsaturated hydraulic conductivities of laboratory-compacted samples of Ste.
Rosalie clay were measured, and the values obtained were corrected for the
effective changing porosity under increasing pressure gradients. An equation
was presented that permits predicting the corrected hydraulic conductivity as a
function of compaction in terms of porosity.
78:02G-025
USE OF METHANOL-WATER SOLUTIONS FOR FREEZE PROTECTION OF TENSIOMETERS,
Wendt, C.W., Wilke, O.C., and New, L.L.
Texas A & M University, Lubbock, Agricultural Research and Extension Center.
Agronomy Journal,' Vol. 70, No. 5, p 890-891, September-October, 1978. 2 fig, 1
tab.
Descriptors: Frozen soils, Freezing, Tensiometers, Irrigation, Soil water, Soil
water movement.
The use of tensiometers to schedule irrigations has been limited primarily to
summer crops because of water freezing in the tensiometers during the winter
months. Since methanol-water mixtures have lower freezing points than water, a
greenhouse study was conducted.using an Olton loam soil (Acridic Paleustolls) to
determine the effect of a methanol-water mixture (30% methanol by volume) on
tensiometer readings and plant growth. No major effects of tensiometer readings
or plant growth were noted. Results from a field demonstration on irrigated
winter wheat (Triticum aestivum L.) indicate that tensiometers with such
mixtures can be used to estimate soil water tension changes at atmospheric
temperatures down to -18.8 C.
78:020-026
EVALUATION OF PEAT AND GRANULAR INOCULUM FOR SOYBEAN YIELD AND N FIXATION UNDER
IRRIGATION,
Bezdicek, D.F., Evans, D.W., Abede, B., and Witters, R.E.
Washington State University, Pullman, College of Agriculture Research Center.
Agronomy Journal, Vol. 70, No. 5, p 865-868, September-October, 1978. 1 fig,
5 tab, 15 ref.
Descriptors: Nitrogen fixation, Carriers, Soybeans, Peat, Granules, Symbiosis.
The purpose of this study was to evaluate peat and granular inoculum for effec-
tiveness in nodulation, N fixation, and yield of soybeans in a soil deficient in
N. Maximum yield response from inoculation (less control) was 3,454 kg/ha
(51.4 bu/A) in 1975 and 2,547 kg/ha (37.9 bu/A) in 1976. Total N fixed was
estimated to be as high as 311 and 263 kg/ha in 1975 and 1976, respectively.
35
-------
The proportion of plant N derived from N fixation ranged from 71 to 80%.
Estimates of total N fixed based on acetylene reduction were half of those
based on total plant N. In general, higher soybean yield and better nodulation
were obtained with the granular than peat carriers, although in these instances,
higher-than-recommended rates of granular carriers were used. These studies
show that soybeans are capable of fixing over 300 kg/ha of N, an amount which is
considerably higher than that reported elsewhere. The data suggest that in
soybean-growing areas where 25 to 40% of the total N is from fixation, the soy-
bean symbiotic N-fixing system is capable of fixing sufficient N for yields far
beyond that now reported.
78:02G-027
STUDY OF THE RELATIVE EFFICIENCY OF FINITE DIFFERENCE AND GALERKIN TECHNIQUES
FOR MODELING SOIL-WATER TRANSFER,
Hayhoe, H.N.
Department of Agriculture, Ottawa, Ontario, Canada, Chemistry and Biology
Research Institute.
Water Resources Research, Vol. 14, No. 1, p 97-102, February, 1978. 8 fig, 2
tab, 14 ref.
Descriptors: *Infiltration, *Soil water, *Soil water movement, *Model studies,
Mathematical models. Numerical analysis, Analytical technique, Moisture content,
Soils, Soil science.
Horizontal infiltration of water into a dry soil was used to study the effi-
ciency of finite difference and Galerkin procedures in accurately locating the
steep wetting front.. The location of the wetting front was determined by a
quasi-analytic solution to Richard's equation. The Galerkin technique was evalu-
ated by using linear, Hermite cubic, and Lagrange quintic elements. These
schemes were compared with the performances of the Crank-Nicolson central dif-
ference method where a standard and a modified averaging procedure for soil-
water diffusivity on grid subintervals is utilized. The comparisons were made
on the basis of error as a function of spatial grid refinement and the relative
efficiency in achieving a practical level of accuracy. The results lead to the
conclusion that the Galerkin scheme with linear elements or the finite differ-
encing scheme with the modified averaging procedure is preferable to the other
techniques.
78:02G-028
VARIABILITY OF HYDRAULIC CONDUCTIVITY WITHIN AND BETWEEN NINE WISCONSIN SOIL
SERIES,
Baker, F.G.
Wisconsin University, Madison, Department of Soil Science.
Water Resources Research, Vol. 14, No. 1, p 103-108, February, 1978. 3 fig, 2
tab, 17 ref.
Descriptors: *Hydraulic conductivity, *Moisture content, "Variability, *Soil
types, *Wisconsin, Soil horizons, Infiltration, Soils, Soil water, Soil water
movement.
Hydraulic conductivity was measured in selected subsurface horizons of nine soil
series by using the crust test method. Measurements were made for several mois-
ture potentials in the range 0 to -150 cm of water at several randomly selected
sites per soil series. The morphological character of the soil series spanned a
broad range, from sands to clay loam soils. The hydraulic conductivity charac-
teristic of each series was described mathematically and the series conductivity
curves were related as a family of curves. By using multivariate discriminant
analysis, the series were grouped.into classes of similar hydraulic behavior,
based on the dispersion of moisture potential and hydraulic conductivity data
within and between series. A 95% prediction interval was constructed to include
the range of conductivities to be expected at future sites.
78:02G-029
EFFECT OF SOIL MATRIC POTENTIAL AND SEEDING DEPTH ON EMERGENCE OF BARLEY,
Sepaskhah, A.R., and Ardekani, E.R.
36
-------
Pahlavi University, Shiraz, Iran, Department of Irrigation.
Agronomy Journal, Vol. 70, No. 5, p 728-731, September-October, 1978. 4 tab
17 ref, 6 equ.
Descriptors: Barley, Germination, Emerging vegetation stage, Seeds, Moisture
tension, Crop production, Crop response.
The effects of soil matric potential and seeding depth on emergence percent and
rate of emergence of barley were investigated. Seedling emergence of 'Zarjo'
cultivar of barley was measured in a Calcixerillic Xerochrept soil at -0.6 to
-30.0 bars soil matric potentials and at 2 to 12 cm seedling depths in the
greenhouse. Cultivar response to seedling depth was determined by seedling
emergence measurements of 'Torsh1, Zargo, and 'Shaneii1 cultivars at seeding
depths of 2 to 12 cm under the same experimental conditions. Soil matric poten-
tial of -30.0 bars reduced the seedling emergence of Zarjo and resulted in the
lowest emergence rate. However, soil matric potentials of -0.6 and -1.5 bars
also reduced Zarjo emergence at the 12-cm seeding depth. Seedling emergence and
emergence rate of Zarjo were lower at the 12 cm seeding depth at all levels of
soil matric potentials. The emergence rate was also reduced at the 8-cm seeding
depth, but only at -30.0 bars. Seedling emergence of Shaneii was found to be
lower than that of the Torsh and Zarjo cultivars. The rates of emergence of the
cultivars were not greatly different at the various seeding depths.
78:02G-030
ALTERNATE DRYING AND REWETTING EFFECTS ON CHEMICAL AND PHYSICAL PROPERTIES AND
MOISTURE-SALINITY RELATIONSHIPS OF A HISTOSOL,
Giskin, M., and Levin, I.
Agricultural Research Organization, Bet Dagan, Israel, The Volcani Center.
Agronomy Journal, Vol. 70, No. 3, p 445-447, May-June, 1978. 1 fig, 2 tab,
J--? jT6£ *
Descriptors: Organic soils, Drying, Wetting, Soil management, Soil chemical
properties, Soil physical properties, Moisture content, Electrical conductance.
Irrigation.
The purpose of the study was to investigate the possible influences on soil
management of changes in chemical and physical properties resulting from a
Histosol being carried through several successive dryings and wettings. Soil
from the 0 to 30 cm layer of a low moor Histosol with a pH of 7.6 and organic
matter content of 55.3% was used. The soil was put through three successive
cycles of air-drying and rewetting; subsamples were removed at each stage and
physical and chemical determinations were carried out. The saturation percent-
age of the field sample decreased from 95.9 to 87.3% after the third drying
cycle. The electrical conductivity of the saturation extract decreased at each
drying stage, due to the large differences in the nitrate content between the
dry and wet stages (8 vs. 380 ppm). Moisture retention curve data showed a 5%
difference in available water between the moist field sample and the same sample
after air-drying. The data showed that laboratory measurements of soil-water
relations for a Histosol change with time, i.e., with each exposure to drying
and rewetting prior to sampling. This information will have a direct bearing on
the management of a Histosol.
78:02G-031
SOIL MOISTURE SENSING WITH AIRCRAFT OBSERVATIONS OF THE DIURNAL RANGE OF SURFACE
TEMPERATURE,
Schmugge, T., Blanchard, B., Anderson, A., and Wang, J.
National Aeronautics and Space Administration, Greenbelt, Maryland, Goddard
Space Flight Center.
Water Resources Bulletin, Vol. 14, No. 1, p 169-178, February, 1978. 7-fig.
1 tab, 7 ref. *
Descriptors: *Remote sensing, *Soil moisture, *Soil temperature, *Arizona,
Soil surfaces. Temperature, Diurnal, Crops.
Aircraft observations of the surface temperature were made by measurements of
the thermal emission in the 8-14 micrometer band over agricultural fields
37
-------
around Phoenix, Arizona. The diurnal range of these surface temperature
measurements was well correlated with the ground measurement of soil moisture
in the 0-2 cm layer. The surface temperature observations for vegetated fields
were found to be within 1 or 2C of the ambient air temperature, indicating no
moisture stress. These results indicated that for clear atmospheric conditions
remotely sensed, surface temperatures can be a reliable indicator of soil
moisture conditions and crop status.
78:02G-032
NUTRIENT EFFECTIVENESS IN RELATION TO RATES APPLIED FOR POT EXPERIMENTS: I.
NITROGEN AND POTASSIUM,
Terman, G. L., and Mortvedt, J.J.
National Fertilizer Development Center, Muscle Shoals, Alabama, Soils and
Fertilizer Research Branch.
Soil Science Society of America Journal, Vol. 42, No. 2, p 297-302, March-April,
1978. 7 fig, 7 ref.
Descriptors: Fertilizers, Nutrients, Nitrogen, Potassium, Phosphorus, Rates of
application. Greenhouses, Corn (field), Rice, Crop response.
A N source experiment was conducted on infertile Mountview sil (Typic Paleudult)
to evaluate four N sources at multiple rates of applied N and P. Granular
ammonium nitrate (AN), sulfur-coated urea (SCU), oxamide (Ox), and isobutylidene
diurea (IBDU) were evaluated for corn (Zea mays L.) at N rates of 0, 400, 800,
and 1,200 mg/pot (5 kg of soil), each at P rates of 0, 60, 120, 480, and 960
mg/pot. Yield response to applied N was in the order AN » SCU > Ox > IBDU at
the higher rates of applied P. At 60 and 120 mg of applied P/pot, however, P
was too deficient for satisfactory evaluation of the N sources. In an experi-
ment with flooded rice (Oryza sativa L.), P limited yields less than did N. In
other N-P and P-K factorial experiments, rates of other nutrients and length of
growth period also greatly affected crop response to applied N and K.
78:02G-033
NUTRIENT EFFECTIVENESS IN RELATION TO RATES APPLIED FOR POT EXPERIMENTS: II.
PHOSPHORUS SOURCES,
Mortvedt, J.J., and Terman, G.L.
National Fertilizer Development Center, Muscle Shoals, Alabama, Soils and
Fertilizer Research Branch.
Soil Science Society of America Journal, Vol. 42, No. 2, p 302-306, March-April,
1978. 4 fig, 3 tab, 12 ref.
Descriptors: Nutrients, Rates of application, Phosphorus compounds, Fertil-
izers, Greenhouses, Corn (field), Crop response, Crop production.
Three greenhouse pot experiments were conducted with corn (Zea mays L.) grown on
infertile soils to evaluate four fertilizers as sources of P. The granular
sources were concentrated superphosphate (CSP, 90% of P water-soluble), mono-
ammonium phosphate (MAP, 100% of P water-soluble), a mixture of 30% of the P as
CSP and 70% as dicalcium phosphate (DCP, water-insoluble), and a 10-90% mixture
of CSP and DCP. yarious rates of P per plot from each source were compared.
These P sources and rates were compared at various levels of N and K. The order
of effectiveness was the same at all levels of applied N and K: MAP > CSP > 30%
CSP + 70% DCP > 10% CSP + 90% DCP. This indicates that on these soils, P was
the chief limiting nutrient at all levels of N and K, However, yield levels and
the precision'of determining differences in effectiveness among sources relative
to experimental error increased greatly at higher rates of applied N and K.
78:020-034
RAPID ESTIMATE OF UNSATURATED HYDRAULIC CONDUCTIVITY FUNCTION,
Bresler, E., Russo, D., and Miller, R.D.
Agricultural Research Organization, Bet Dagan, Israel, Division of Soil Physics.
Soil Science Society of America Journal, Vol. 42, No. 1, p 170-172, January-
February, 1978. 4 fig, 10 ref.
38
-------
Descriptors: *Hydraulic conductivity, *Unsaturated flow, *Infiltration,
*Estimating equations, Laboratory tests, Soil physical properties, Pore
pressure, Pore water, Horizontal infiltration, Wetting front.
From results of Reichardt, Nielsen, and Biggar and of Russo and Bresler, it was
inferred that a laboratory horizontal infiltration experiment with air-dry soil
yields an estimate of the saturated-unsaturated hydraulic conductivity function
given by K(h) = 0.27(m to the 4th power)(h sub e/h) to the 2.6 power or K(theta)
= 0.27(m to the 4th power)(theta - theta sub d)(theta sub w - theta sub d)) to
the 7.2 power. Here m = dx/d(t to the 1/2 power); x is distance to the wetting
front and t is infiltration time; theta sub d and theta sub w are water contents
of air-dry and "unsaturated" soil; h is pore water pressure head, and h sub e is
the air entry value of h. These relationships can serve as a general approxi-
mation of K(theta) and K(h) in nonsodic stable soils. Field measurements of h
sub e and saturated K can also be used to derive K(theta) and K(h).
78:02G-035
THE ROLE OF NITRATE DIFFUSION IN DETERMINING THE ORDER AND RATE OF DENITRIFICA-
TION IN FLOODED SOIL: I. EXPERIMENTAL RESULTS,
Reddy, K.R., Patrick, W.H., Jr., and Phillips, R.E.
North Carolina State University, Raleigh, Department of Biological and Agricul-
tural Engineering.
Soil Science Society of America Journal, Vol. 42, No. 2, p 268-272, March-April,
1978. 5 fig, 3 tab, 18 ref.
Descriptors: Denitrification, Nitrates, Anaerobic conditions, Flooding, Sub-
mergence, Nitrogen, Diffusion, Incubation.
In this study, 15 soils from various locations in the U.S. were amended with
0.5% rice straw and incubated under saturated conditions without 02, either with
no excess floodwater or with a 3-cm overlying layer of floodwater. The dis-
appearance of added and native N03(-)-N and its conversion to N2 and N20 fol-
lowed apparent zero-order reaction kinetics when all the N03(-)-N was present in
the active soil layer (no excess floodwater). When added N03(-)-N was present
in both the floodwater and the soil layer, N03(-)-N disappearance followed
apparent first-order reaction kinetics. A decrease in N03(-)-N concentration in
the soil layer caused NO3(-)-N in the floodwater to diffuse into the soil layer
(a first-order reaction with respect to N03(-)-N concentration) where it was
denitrified. The rate of denitrification was faster in soils incubated with no
excess floodwater compared to soils incubated under 3 cm of floodwater. One soil
(Crowley silt loam), when incubated with no added carbon source and no excess
floodwater, showed N03(-)-N disappearance to follow first-order kinetics. When
this soil was incubated with an additional carbon source, NO3(-)-N disappearance
was zero-order.
78:02G-036
THE ROLE OF NITRATE DIFFUSION IN DETERMINING THE ORDER AND RATE OF DENITRIFICA-
TION IN FLOODED SOIL: II. THEORETICAL ANALYSIS AND INTERPRETATION,
Phillips, R.E., Reddy, K.R., and Patrick, W.H., Jr.
Kentucky University, Lexington, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 2, p 272-278, March-April,
1978. 7 fig, 13 ref, 12 equ, 1 append.
Descriptors: Denitrification, Nitrates, Flooding, Submergence, Nitrogen, Diffu-
sion, Theoretical analysis.
A theoretical analysis.of denitrification occurring in submerged soil in a test
tube, when assumed to be a zero-order reaction with available organic carbon
nonlimiting, appears to be a first-order reaction if the effects of diffusion
are neglected. This is so because denitrification occurs at a faster rate than
the diffusive flux can supply NO3(-j-N to the soil. After some length of time,
the concentration of NO3(-)-N in the lower portion of the flood-water-soil inter-
face will be equal to the concentration in the flood-water. After which time,
denitrification occurs only in the upper portion of the soil sample. It is
suggested that the true order of reaction and rate constant of denitrification in
a test tube can be evaluated experimentally by eliminating the floodwater above
39
-------
the soil sample; with this experimental geometry some of the confounding effects
of diffusion of N03(-)-N can be minimized. If diffusion is neglected, not only
is the order of reaction misjudged but the depth of floodwater above the soil
has a significant effect on the magnitude of the calculated rate constant of the
apparent first-order reaction also.
78:02G-037
RELATIONSHIP TO EXTRACTABLE SOIL MANGANESE TO SOIL PROPERTIES,
Shuman, L.M., and Anderson, O.E.
Georgia University, Experiment, Department of Agronomy.
Soil Science Society of America Journal-, Vol. 42, No. 4, p 666-667, July-August,
1978. 2 tab, 8 ref.
Descriptors: Manganese, Soil chemical properties, Soil physical properties,
Ammonium compounds, Organic matter, Cation e-xchange, Greenhouses, Soil chemistry.
In a greenhouse experiment eight Southeastern soils were amended to give pH
levels of 4.8, 5.8, and 6.8 and were treated with 0, 25, and 50 ppm Mn. After
growing wheat (Triticum aestivium L.) for 40 days, the soils were extracted for
Mn using six extractants: H20, neutral IN NH40Ac (with and without 0.2% hydro-
quinone), "double acid", diethylenetriaminepentaacetic acid (DTPA) and ethylene-
diaminedi-o-hydroxyphenylacetic acid (EDDHA). Except for the low-Mn soils,
greater differences in extractable Mn were observed among soil types and soil pH
levels than among Mn rates. Extractable Mn was correlated with soil clay con-
tent and total soil Mn. Organic matter content with a narrow range from 1.0 to
2.9%, silt content and cation exchange capacity (CEC) were not correlated with
extractable Mn. The extractable Mn decreased as soil pH increased for the H20,
NH40Ac alone, and DTPA extractants making them preferable for predicting soil
Mn availability since higher pH causes Mn to be less available to the plant.
78:02G-038
A SOIL MOISTURE BUDGET MODEL ACCOUNTING FOR SHALLOW WATER TABLE INFLUENCES,
Stuff, R.G., and Dale, R.F.
Purdue University, West Lafayette, Indiana, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 4, p 637-643, July-August,
1978. 9 fig, 1 tab, 15 ref, 10 equ.
Descriptors: Soil moisture, Evapotranspiration, Capillary water, Water balance,
Field capacity, Moisture deficit, Computer models, Water table.
Soil moisture balance programs developed on well-drained soils were found to be
unsatisfactory for a soil underlain by shallow water tables, a condition typical
of about 9 million acres of cropland in Indiana. Capillary rise past a 105-cm
root zone boundary was estimated as the difference between estimated evapotrans-
piration (ET) and changes in soil moisture under corn (Zea mays L.) on a tile-
drained Typic Argiaquoll at West Lafayette, Indiana, during three growing
seasons, 1971-1973. Capillary water was found to supply an average of 27% of
the ET in periods with little or no precipitation. Computer model estimates
showed capillary water to furnish about 17% of the total ET over a 100-day
period from 49 days*before silking to 50 days after. The derived relationships
with those obtained from literature sources and assumptions regarding runoff and
recharge were programmed in a computer model for simulating the daily moisture
conditions. The model was found to closely track measurements of both soil
moisture and water table depths in four independent seasons: early and late
plantings in 1970 and 1974.
78:02G-039
SALT OUTFLOWS FROM NEW AND OLD IRRIGATED LANDS,
Carter, D.L., and Robbins, C.W.
Idaho University, Kimberly, Snake River Conservation Research Center.
Soil Science Society of America Journal, Vol. 42, No. 4, p 627-632, July-August,
1978. 3 fig, 3 tab, 13 ref.
Descriptors: Salinity, Leaching, Leachate, Drainage water, Water quality, Salt
balance, Irrigated land.
40
-------
Three water application treatments with low salt water were applied to previously
nonirrigated soil and to a similar soil which had been irrigated for 67 years.
The total soluble salt content of these soils initially, and after one and two
seasons of treatment, was measured to determine salt outflow. Residual soluble
salts were esse.ntially removed from the previously nonirrigated soil after 30 cm
of water/m depth of soil had passed from the soil as leachate, regardless of the
number of seasons required for that amount of leaching. The total quantity of
residual salt removed from soil 5 m deep was 70 metric tons/ha, with about 38
metric tons/ha being leached out by the first 14 cm of leachate. After the
residual salt was removed, the salt content of the newly irrigated soil was the
same as that of the soil which had been irrigated for 67 years. Subsequent salt
outflow from the soil was directly related to the quantity of water leaching
through the soil, indicating .that more minerals dissolved with more leaching.
Soils irrigated for many years and then not irrigated for up to 10 years had no
measurable reaccumulation of soluble salts during the period of nonirrigation.
78:020-040
EFFECTS OF SOIL MOISTURE ON THE DIFFUSION COEFFICIENTS AND ACTIVATION ENERGIES OF
TRITIATED WATER, CHLORIDE, AND METRIBUZIN,
Scott, H.D., and Paetzold, R.F.
Arkansas University, Fayetteyille, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 1, p 23-27, January-
February, 1978. 3 fig, 2 tab, 25 ref.
Descriptors: *Diffusion, *Soil moisture, *Solutes, Laboratory tests. Moisture
content, Soils, Soil horizons, Adsorption, Radioisotopes, Tritium.
Diffusion coefficients of tritiated water, chloride, and metribuzin were deter-
mined in Captina silt loam as functions of soil water content and soil tempera-
ture. Tritiated water and metribuzin were found to diffuse in both liquid and
vapor phases, whereas chloride diffusion was restricted to the solution phase.
For a given soil water content, values of the diffusion coefficients were larger
in soil samples from the Ap horizon than in those from the B2t horizon for
tritiated water and chloride. This was attributed to the greater tortuosity in
the B2t horizon. Metribuzin had similar diffusion coefficients in both horizons,
apparently reflecting offsetting effects due to the greater adsorption by the Ap
and greater tortuosity in the B2t. Thermodynamic studies indicated that the
energy requirement for diffusion of these solutes was inversely related to soil
moisture content for tritiated water and metribuzin. Activation energies for
chloride diffusion were lower than for other solutes at equal soil water contents.
78:020-041
LINEAR AND NONLINEAR MODELS OF INFILTRATION FROM A POINT SOURCE,
Ben-Asher, J., Lomen, D.O., and Warrick, A.W.
Arizona Water Resources Research Center, Tucson.
Soil Science Society of America Journal, Vol. 42, No. 1, p 3-6, January-February,
1978. 6 fig, 11 ref.
Descriptors: *Infiltration, *Irrigation, *Soil water movement, *Model studies,
Mathematical models. Analytical techniques, Equations, Soils, Soil water, Soil
types.
Numerical and analytical solutions for water flow from a point source were com-
pared. The numerical solution was for the nonlinear moisture flow equation, and
the analytical solution was for the corresponding linearized form. For cyclic
conditions, results were approximately the same with regard to range in values
between the wettest and driest values. However, the numerical results showed a
faster response both for wetting and drying. Computational times required of the
analytical solution were of the order of 1/20 to l/200th of that required for the
finite difference solutions.
78:026-042
HYDRAULIC CONDUCTIVITY OF UNSATURATED POROUS MEDIA: GENERALIZED MACROSCOPIC
APPROACH,
Mualem, Y.
41
-------
Colorado State University, Fort Collins, Engineering Research Center.
Water Resources Research, Vol. 14, No. 2, p 325-334, April, 1978. 2 fig, 5 tab,
41 ref.
Descriptors: *Hydraulic conductivity, *Porous media, *Unsaturated flow, *Mathe-
matical models, Equations, Theoretical analysis, Soil texture, Statistical
models, Porosity, Specific yield.
The macroscopic approach which yields the power function relationship between
the relative permeability and the effective saturation, K sub r = S sub e to the
n power, was generalized to allow n to vary with the soil type. Theoretical
analysis shows that n may receive values lower than 3.0 for granular porous
media and higher than 3.0 for soils of the fine texture. These findings were
verified by using experimental data of 50 soils. The lower limit of n was
found to be 2.5, while high values (up to n = 24.5) were found for the-fine-
textured soils. Statistical analysis of the measured data of the 50 soil sam-
ples showed a significant correlation between n and w, which indicates the
amount of work per unit volume of soil required to drain a saturated soil to the
wilting point. By using the soil characteristics psi-theta, an empirical formula
was derived which relates n to w by n = 0.015w + 3.0. This proposed model was
compared with the two previous versions of Averjanov and Irmay on the basis of
the experimental data of the 50 soils. A very good agreement was found between
the measured K sub r - theta curves and the theoretical ones, derived by the new
model, for granular soils as well as for soils of fine texture where the other
models very often fail. The accuracy of the new model is competitive with the
best of the statistical models analyzed by Mualera. By this study, the power
function model gains a high degree of accuracy, which compounded by its simpli-
city, produces an efficient tool for prediction of the hydraulic conductivity of
unsaturated soils.
78:02G-043
SOLUTE TRANSPORT DURING ABSORPTION OF WATER BY SOIL: LABORATORY STUDIES AND
THEIR PRACTICAL IMPLICATIONS,
Smiles, D.E., and Philip, J.R.
Commonwealth Scientific and Industrial Research Organization, Canberra City,
A.C.T. 2601, Australia, Division of Environmental Mechanics.
Soil Science Society of America Journal, Vol. 42, No. 4, p 537-544, July-August,
1978. 4 fig, 1 tab, 14 ref, 21 equ.
Descriptors: Leaching, Unsaturated flow, Absorption, Scaling, Infiltration,
Capillary action.
An experimental study of solute transport during absorption into uniform
horizontal soil columns is reported. The inferred dispersion coefficient is
essentially independent also of the volumetric moisture content (at least in the
range 0.18-0.28). It is approximately equal to the product of the volumetric
moisture content and the molecular diffusivity of KC1 in water. The practical
implications of the work for field problems are. explored, use being made of
scaling theory for flow processes involving capillarity and viscous flow. It is
concluded that, for the majority of field soils, solute transport during unsat-
urated flow of any practical duration may be described by a velocity-independent
dispersion coefficient. This represents a very great simplification of the
formulation, analysis, and prediction of solute transport in such systems. The
observed pistonlike displacement of the initial water in the columns by the
absorbed wat^er suggests that there is no basis for subdividing the water in the
system into mobile and immobile fractions. Further theoretical and experimental
work is under way on solute transport during infiltration, and during absorption
into very coarse-textured soils (for which the dispersion coefficient is not
velocity independent.)
78:02G-044
STEADY INFILTRATION FROM SINGLE AND PERIODIC STRIP SOURCES,
Batu, V.
Karadeniz Technical University, Trabson, Turkey, Department of Civil Engineering.
Soil Science Society of America Journal, Vol. 42, No. 4, p 544-549, July-August,
1978. 7 fig, 15 ref, 49 equ.
42
-------
Descriptors: Infiltration, Soil water, Fourier analysis, Hydraulic conductivity.
Sprinkler irrigation.
The matric flux potential and horizontal and vertical flux distributions were
obtained using Fourier analysis techniques for single and periodic strip sources
located on the soil surface. The theory is based on the assumption that the
hydraulic conductivity is an exponential function of the soil water potential.
The matric flux potential distributions were compared with the results obtained
by Warrick and Lomen (1976, Soil Sci. Soc. Am. J. 40:639-643) who used different
mathematical techniques.
78:02G-045
TRANSIENT CHANGES IN THE SOIL-WATER SYSTEM FROM IRRIGATION WITH SALINE WATER-
I. THEORY,
Jury, W.A., Frenkel, H., and Stolzy, L.H.
California University, Riverside, Department of Soil and Environmental Science.
Soil Science Society of America Journal, Vol. 42, No. 4, p 579-585, July-August
1978. 5 fig, 5 tab, 15 ref, 11 equ.
Descriptors: Saline water, Soil water movement, Chemical precipitation.
Leaching, Diffusion, Travel time, Cation exchange, Dispersion, Irrigation water.
Transient soil solution concentrations and salt precipitation rates in the root
zone are shown to be influenced by the ion composition and concentration of the
applied water and soil exchange complex as well as by the water uptake distri-
bution and infiltration rate. Calculations are performed on three kinds of
infiltration water to estimate the ionic composition of the soil solution, the
rate of gypsum and CaCO3 precipitation, and the time to reach steady state for a
given irrigation management. Solution concentrations adjusted for exchange
interactions were shown to precipitate twice the quantity of salt in a given
time, resulting in lowered solution concentration and altered composition
Ca(2+), Mg(2+), Na(2+), and S04(2-) ion concentrations in the solution phase,
with up to 1,600 days required to reach steady state through the top 150 cm for
a leaching fraction of 0.05. The extent of precipitation is also found to
depend strongly on the concentration of sulfate and degree of saturation with
gypsum in the irrigation water. Diffusion and dispersion are also shown to
influence the duration of the transient phase.
78:02G-046
TRANSIENT CHANGES IN THE SOIL-WATER SYSTEM FROM IRRIGATION WITH SALINE WATER:
II. ANALYSIS OF EXPERIMENTAL DATA,
Jury, W.A., Frenkel, H., Devitt, D., and Stolzy, L.H.
California University, Riverside, Department of Soil and Environmental Science.
Soil Science Society of America Journal, Vol. 42, No. 4, p 585-590, July-August,
1978. 4 fig, 7 tab, 13 ref, 3 equ.
Descriptors: Saline water, Soil water movement, Cation exchange, Chemical
precipitation, Solutes, Irrigation water, Wheat, Sorghum, Lysimeters.
Twenty-three lysimeters containing four soil types with alternate wheat (Triticum
aestivum L.) and sorghum (Sorghum vulgare Pers.) crops were irrigated with three
synthesized levels (2.2, 3.9, 7.1 mmho/cm) of"irrigation water. Salt balance was
calculated from soil salinity sensor electrical conductivity EC measurements by
determining a relationship between solution EC and solution concentration using a
chemical equilibrium model. Exchangeable cations were measured after the third
crop. All methods of determining salt balance showed the order of 50% salt
precipitation over the first 500 days of the experiment, approximately two times
the expected amount when root zone salt concentrations have reached steady state.
Release of Ca(2+) ions from exchange sites and subsequent enhanced gypsum and
Ca CO3 precipitation was assumed to be responsible for the difference between
transient and steady-state behavior. The drainage composition of a lysimeter
which had moved one pore volume through the root zone showed that only Cl(-) was
approaching a steady-state value. Exchange effects and enhanced precipitation
were assumed to be buffering the concentration of the other ions. Water uptake
in all lysimeters was occurring primarily in the top 20 cm, a consequence of high
irrigation water salinity and daily irrigation.
43
-------
78:02G-047
MOISTURE PROFILES DURING STEADY VERTICAL FLOWS IN SWELLING SOILS,
Giraldez, J.V., and Sposito, G.
California University, Riverside, Department of Soil and Environmental Sciences.
Water Resources Research, Vol. 14, No. 2, p 314-318, April, 1978. 3 fig, 1 tab,
21 ref, 10 equ.
Descriptors: Steady flows, Soil water movement, Saturated flow, Unsaturated
flow, Profiles, Overburden.
Practical working equations for describing numerically soil moisture profiles in
homogeneous swelling soils during steady vertical flows were developed. These
equations were solved on a computer with soil water and swelling curve data
appropriate to Rideau clay loam, which was taken as a typical example of a
swelling soil. Unsaturated swelling soils were shown to exhibit either xeric
or hydric profiles for downward flows, whereas for upward flows they exhibit
only a zeric profile, just as rigid soils do. On the other hand, saturated
swelling soils were shown to have hydric profiles in the downward flow situation
and either hydric or zeric profiles during upward•flows. The overburden or
"envelope pressure" potential was shown to exert a great influence, in almost
all circumstances, in reducing the maximum evaporative flow from a shallow water
table in a swelling soil as compared to the equivalent nonswelling case.
78:020-048
A TWO-DIMENSIONAL LINEARIZED VIEW OF ONE-DIMENSIONAL UNSATURATED-SATURATED FLOW,
Cushman, J., and Kirkham, D.
Iowa State University; Ames, Department of Agronomy.
Water Resources Research, Vol. 14, No. 2, p 319-323, April, 1978. 4 fig, 16 ref.
Descriptors: *Saturated flow, *Unsaturated flow, *Mathematical models, *Numer-
ical analysis, Equations, Finite element analysis, Infiltration, Moisture con-
tent, Pressure head, Theoretical analysis.
A numerical analysis of the one-dimensional, unsaturated-saturated flow problem
was presented. Both the pressure head and moisture- content equations were
studied for vertical and horizontal infiltration, respectively. The problems
were considered in a two-dimensional setting in which time was considered the
second dimension. The numerical scheme used was finite element analysis
coupled with a simple linearizing assumption. The numerical process was com-
pared with various other analytic and numerical solutions of the same problems.
It was shown that if the size of the elements is not too large, the method is
very accurate.
78:02G-049
ON OSCILLATION OF NUMERICAL SOLUTION OF A MODIFIED RICHARDS' EQUATION,
Krishnamurthi, N., Sunada, O.K.,. and Longenbaugh, R.A.
Utah International Incorporated, San Francisco, California, Department of
Environmental Quality.
Water Resources Research, Vol. 14, No. 1, p 52-54, February, 1978. 1 fig,
16 ref, 8 equ.
*
Descriptors: Mathematical studies, Numerical analysis, Soil water movement,
Hydraulic conductivity, Gravitational water, Diffusivity.
Numerical solutions of differential equations should be checked for the condi-
tions of consistency, convergence, and stability. The implicit solutions that
satisfy these conditions are sometimes found to be oscillatory about the true
solutions. The reasons for these oscillations are explained. A method to derive
criteria for nonoscillatory solutions of a nonlinear partial differential equa-
tion is outlined. These criteria for modified Richards' equation are presented,
and their physical significances are explained.
78:02G-050
DENITRIFICATION IN FOUR CALIFORNIA SOILS: EFFECT OF SOIL PROFILE
CHARACTERISTICS,
44
-------
Gilliam, J.W., Dasberg, S., Lund, L.J., and Focht, D.D.
California University, Riverside, Department of Soil Science and Agricultural
Engineering.
Soil Science Society of America Journal, Vol. 42, No. 1, p 61-66, January-February,
1978. 4 fig, 3 tab, 25 ref.
Descriptors: Denitrification, Soil profiles, Steady flow, Soil water movement,
Nitrates, California.
The effects of soil profile characteristics upon rate and products of denitrifica-
tion were investigated using four soils in laboratory columns under steady-state
water flow conditions. Soils with heavy textured subsoils readily reduced added
N03(-). However, the soil with the lowest clay content had restricted water flow
in the surface horizon and reduced the greatest amount of N03(-). It was con-
cluded that any soil condition which impedes water flow will be positively related
to denitrification and that spatial variability in denitrification is likely to be
as great as observed variability in water movement. The ratio of N2 to N2O found
during denitrification was extremely variable with measured values from 100:1 to
1:4.- The low concentrations of N20 measured during denitrification occurred in
soils where the denitrification was occurring deep in the soil profile, but there
was no indication that this low concentration was a result of further reduction of
N20 as N2O diffused through the soil profile. Our data indicate that it is
currently not possible to accurately predict relative amounts of N2 and N2O which
will be produced during most denitrification in soils, and that estimates of that
N2O produced from agricultural lands have a large uncertainty factor.
78:02G-051
RESIDUAL FERTILIZER NITROGEN IN A FLOODED RICE SOIL,
Reddy, K.R., and Patrick, W.H., Jr.
North Carolina State University, Raleigh, Department of Biological and
Agricultural Engineering.
Soil Science Society of America Journal, Vol. 42, No. 2, p 316-318, March-April,
1978. 2'fig, 4 tab, 2 ref.
Descriptors: Nitrogen, Stable isotopes, Fertilization, Rice, Flood irrigation,
Incubation, Nutrients.
Residual effects of 15N-labelled fertilizer (ammonium sulfate) nitrogen were
measured during the second cropping season of rice (Oryza sativa L.). During the
first cropping season, labelled fertilizer N was applied at 100 kg N/ha using
different methods of N application. At the end of harvest the rice straw obtained
during the first cropping season was incorporated back into the respective plots.
During the second season half the plots were treated with an additional 100 kg N/ha
of nonlabelled fertilizer N as an early season top dressing. The uptake of residual
labelled N was measured during the growing season and at harvest time under ferti-
lized and nonfertilized conditions. The recovery of residual labelled N in grain
and straw was 2.7 to 3.1 kg N/ha, with a large fraction of N still remaining in
the soil. Approximately 3 to 5 kg of the residual labelled N/ha present at the
beginning of the season was not accounted for in any fraction and was assumed to be
lost from the system. Over a 2-year period, about 66 to 82% of the applied
labelled fertilizer N could be accounted for by plant uptake or in the soil with
the remainder lost from the plant-soil system.
78:02G-052
INFILTRATION DURING AN UNSTEADY RAIN,
Chu, S.T.
South Dakota State University, Brookings, Department of Agricultural Engineering.
Water Resources Research, Vol. 14, No. 3, p 461-466, June, 1978. 1 fig, 3 tab,
12 ref. ,
Descriptors: "-Infiltration, *Rainfall, *Model studies, Mathematical models,
Precipitation (atmospheric), Soil water, Soil water movement, Rainfall intensity,
Precipitation excess, Ponding, Soil moisture, Runoff, Unsteady rain.
Infiltration during a rainfall event can be divided into two distinct stages- a
stage with surface ponding and a stage without surface ponding. Few of the infil-
tration models in current use are suitable to describe infiltration for both
stages. In this paper the Green and Ampt equation was applied to determine the
time that separates these two stages so that infiltration for the different stages
45
-------
can be treated separately. To obtain an integrated form of the Green and Ampt
equation, it is traditionally assumed that the cumulative infiltration is zero
at the time when surface ponding starts. But in a rainfall event, the cumulative
infiltration equals the water infiltrated into the soil profile prior to the
ponding time, which is usually not zero. Therefore, a modification in the tradi-
tional Green and Ampt equation is needed to describe infiltration during a rainfall
event. It was shown that this modification is equivalent to a shift of the time
scale by an amount which was referred to as the pseudotime. The modified version
of the Green and Ampt equation was applied to determine rainfall excess and to
predict total runoff for three major storms recorded by the Agricultural Research
Service from 1957 to 1959 on a watershed near Oxford, Mississippi. A comparison
of the prediction and the measured total runoff appeared to be promising.
78:02G-053
THE STATISTICAL MECHANICAL THEORY OF WATER TRANSPORT THROUGH UNSATURATED SOIL 1.
THE CONSERVATION LAWS,
Sposito, G.
California University, Riverside, Department of Soil and Environmental Sciences.
Water Resources Research, Vol. 14, No. 3, p 474-478, June, 1978. 26 ref, 30 equ.
Descriptors: Soil water movement, Unsaturated flow. Momentum equation, Fluid
mechanics, Continuity equation, Heterogeneity, Soil physics.
The macroscopic differential equations of mass and momentum balance for water in
a rigid unsaturated soil are derived from first principles by using the methods
of statistical mechanics. The derivation begins with the development, at the
molecular level, of expressions for the mass and linear momentum densities of water
in a soil. The derivatives of these expressions with respect to the time then
provide for local balance equations that are ensemble averaged and local volume
averaged in order to produce the macroscopic balance equations. The resulting
macroscopic equations agree with those derived for mass and linear momentum transport
in a soil on the basis of the continuum theory of mixtures. The unified insight
into mass transport processes afforded by a statistical mechanical theory as com-
pared to one evolved from a solely macroscopic view is discussed.
78:02G-054
THE STATISTICAL MECHANICAL THEORY OF WATER TRANSPORT THROUGH UNSATURATED SOIL 2.
DERIVATION OF THE BUCKINGHAM-DARCY FLUX LAW,
Sposito, G.
California University, Riverside, Department of Soil and Environmental Sciences.
Water Resources Research, Vol. 14, No. 3, p 479-484, June, 1978. 18 ref, 55 equ.
Descriptors: Soil water movement, Unsaturated flow, Soil water, Hydraulic
conductivity. Steady flow, Model studies, Markov processes. Soil physics.
The Buckingham-Darcy flux law, an empirical equation that relates the volumetric
flux density of water in an unsaturated soil to the gradient of the total potential,
is derived from first principles by using the methods of statistical mechanics. The
derivation given, a direct application of well-known techniques in nonequilibrium
statistical mechanics, proceeds through a detailed molecular description of two
laboratory experiments for measuring the hydraulic conductivity tensor of a homo-
geneous unsaturated soil. In the first experiment the steady flow of water is
induced by a gradient in the matrie potential, while in the second, flow is induced
by a gradient in the gravitational potential. In both cases, the appropriate
form of the BUckingham-Darcy law is derived on the basis of a linear response
approximation, and an expression for the hydraulic conductivity is given in terms
of a time integral of the correlation function for the velocities of the water
molecules in the soil. The problem of calculating the hydraulic conductivity of
a soil thereby is reduced to quadrature and to the task of developing a molecular
model of the velocity correlations among the water molecules. A recent successful
model of this type is discussed briefly.
78:02G-055
A PARAMETER-EFFICIENT HYDROLOGIC INFILTRATION MODEL,
Smith, R.E., and Parlange, J.Y.
Agricultural Research Service, Fort Collins, Colorado.
46
-------
Water Resources Research, Vol. 14, No. 3, p 533-538, June, 1978. 6 fig, 18 ref.
Descriptors: *Infiltration, *Ponding, *Model studies, Mathematical models,
Rainfall, Hydraulic conductivity, Soil water, Soil water movement. Soils, Soil
types, Equations, Infiltration rates, Hydrology, Infiltration models.
By adopting two extreme assumptions concerning the behavior of unsaturated soil
hydraulic conductivity K near saturation, a two-branched model was derived for
ponding time and infiltration rate decay for arbitrary rainfall rates. One
assumption was that K varies slowly near saturation and leads to an expression
for ponding time and infiltration decay. For initially ponded conditions, ponding
time was zero, and with the rainfall rate approaching infinity, the familiar
Green and Ampt expression results. The other, rather opposite assumption was that
K varies rapidly, e.g., exponentially, near saturation. This model also holds for
both rainfall_and ponded surface conditions, and for ponded conditions the expres-
sion is identical to that of Parlange. Each model uses only two parameters,
saturated soil conductivity K sub s and a parameter that is roughly related to
sorptivity and responds nearly linearly to variations in initial saturation.
Both parameters are physically related to measurable soil properties. Methods
were presented to estimate parameters of either model from infiltrometer tests.
The two models were compared with a precise numerical solution of the unsaturated
soil water diffusion equations for three soils that represent a range of soil
behaviors near saturation. Results showed that either assumption would be an
excellent model for most hydrologic purposes, and the relative goodness of fit
of each model is generally consistent with the appropriate behavior of K, as the
water content approaches the saturated water content.
78:02G-056
BASIC MATHEMATICAL MODELS OF TOXICANT TRANSPORT THROUGH THE SOIL PROFILE,
Rachinskii, V.V.
Timiryazev1 Academy of Agricultural Sciences, Moscow, Union of Soviet Socialist
Republics.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978. Athens, Georgia,
p 201-209. 5 ref, 26 equ.
Descriptors: Pesticide kinetics, Sorption, Dynamics, Mathematical models,
Chromatography, Kinetics, Pesticide toxicity.
This paper discusses basic mathematical models of toxicant transport through
the soil profile; and has developed mathematical expressions for the sOrption
dynamics problems using the kinetic parameter of time lag'and at a variable
velocity of the mobile phase.
78:02G-057
DRAINAGE IN A NATURAL LAYERED PROFILE BY FINITE ELEMENT ANALYSIS,
Khanjani, M.J., and Bloomsburg, G.L.
Idaho University, Moscow, Department of Agricultural Engineering.
Paper No. 78-2036, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p. 8 fig, 1 tab,
5 ref.
Descriptors: Drainage, Finite element analysis, Computer programs, Subsurface
drains. Water table, Porosity, Hydraulic conductivity, Soil properties, Soil
profiles, Pore pressure.
An agricultural soil profile consisting of four different soil types is modeled
by means of a finite element computer program. The results are in the form of
a curve for water table height at midpoint between drains versus a dimensionless
function of time. Composite values for soil properties (apparent, conductivity,
displacement head, and drainage porosity) are calculated, and the result from
running a one layer composite profile are compared to results from an actual
profile. The effect of drain distance above the impermeable layer is also
investigated. The Dupuit-Forchheimer assumptions are not used in this analysis
and unsaturated flow above the water table is considered.
47
-------
78:02G-058
INFLUENCE OF SOIL AIR AND DRAINAGE ON INFILTRATION,
Jarrett, A.R., Hoover, J.R., and Davis, C.L.
Pennsylvania State University, University Park, Department of Agricultural
Engineering.
Paper No. 78-2039, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 8 p. 7 fig, 22 ref.
Descriptors: Infiltration, Infiltration rates, Drainage, Air, Subsurface drainage,
Rainfall, Runoff, Subsurface drains, Surface runoff, Laboratory tests.
The effect of soil air entrapment and subsurface drainage in a sand were evaluated.
During rainfall, the entrapped soil air pressure stopped the infiltration process
converting all precipitation to runoff except when the entrapped air was permitted
to vent via the subsurface drain, at which time infiltration and subsurface drainage
started and runoff ceased.
78:020-059
A SIMPLE FINITE ELEMENT METHOD OF INFILTRATION,
Pall, R., Jarrett, A.R., and Morrow, C.T.
Pennsylvania State University, University Park, Department of Agricultural
Engineering.
Paper No. 78-2068, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 10 p. 14 fig, 12 ref,
8 equ.
Descriptors: Infiltration, Infiltration rates. Soil water movement, Numerical
analysis, Finite element analysis, Darcy's law, Diffusivity, Computer models,
Energy conservation, Soil water.
A numerical solution of one dimensional infiltration was developed from basic
principles of flow and energy conservation using finite element technique. An
exponential relationship between hydraulic diffusivity and volumetric moisture
content was used for diffusivity calculations. Solutions obtained for horizontal
moisture distribution gave an excellent agreement with exact solution of Scott
et al. and numerical solutions of Philip and Hanks 'and Bowers.
78.-02G-060
PREDICTING DISPERSION COEFFICIENTS IN SOILS,
Smajstrla, A.G., Reddell, D.L., and Barnes, P.L.
Texas A & M University, College Station, Department of Agricultural Engineering.
Paper No. 78-2074, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 16 p. 16 fig, 18 ref,
10 equ.
Descriptors: Dispersion, Soil physical properties, Numerical analysis, Hydrologic
properties, Soil water movement,' Capillary water, Diffusion, Simulation analysis,
Model studies, Computer models.
A numerical model was developed to predict the magnitudes of dispersion coefficients
as functions of soil physical and hydrologic properties and solution velocities.
A capillary bundle model was used, and the bundle hydraulic properties were deter-
mined from the hydraulic conductivity function. Interaction between bundles was
described as a diffusion-controlled process. The model'generated breakthrough
curves from simulated steady flow displacement of one soil solution with a second
one. From the breakthrough curves, dispersion coefficients were calculated. The
breakthrough curves and dispersion coefficients were compared with those measured
in the laboratory with good agreement for unsaturated flow conditions and for
saturated flow at low velocities. Agreement during saturated flow at large veloci-
ties was only obtained when a matching factor was used to describe mixing between
capillary bundles.
48
-------
78:02G-061
TRANSIENT FLOW IN UNSATURATED POROUS MEDIA,
Lin, S.H.
Polytechnic Institute of New York, Brooklyn, Department of Chemical Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY7, Proceedings Paper 13886, p 975-982, July, 1978. 4 fig, 12 ref.
Descriptors: *Porous media, *Unsaturated flow,,*Diffusion, Hydraulic conductivity,
Infiltration, Moisture content, Unsteady flow, Silts, Loam, Soil water movement,
Mathematical models, Equations, Orthogonality.
Transient water movement in both horizontal and vertical unsaturated porous media
was investigated. The nonlinear partial differential equation governing the one-
dimensional flow was solved by the orthogonal collocation method. This method
involves the approximation of the spatial derivative terms in the partial differen-
tial equation by an orthogonal polynomial and thus the partial differential
equation is transformed into a set of ordinary differential equations which in
turn-can be integrated numerically. The present numerical solutions were found
to be in excellent agreement with previous solutions for the cases under considera-
tion. Because of its high accuracy, computational stability, and easy implemen-
tation, the orthogonal collocation method can be a very good alternative for
tackling these nonlinear diffusion problems.
78:02G-062
LONGITUDINAL AND TRANSVERSE DISPERSION COEFFICIENTS IN UNSATURATED PLAINFIELD
SAND,
Yule, D.P., and Gardner, W.R.
Wisconsin University, Madison, Department of Soil Science.
Water Resources Research, Vol. 14, No. 4, p 582-588, August, 1978. 7 fig, 2 tab,
19 ref.
Descriptors: *Dispersion, *Soils, *Sands, *Laboratory tests. Instrumentation,
Mathematical models, Soil water movement, Unsaturated flow, Transverse dispersion,
Longitudinal dispersion.
The relationship between the longitudinal and transverse dispersion coefficients
(D sub L and D sub T) and the pore water velocity (v) and the effective diffusion
coefficient (D sub e) was determined for v between 0.01 and 0.28 cm/min in a
vertical unsaturated column (L = 23 cm) of C horizon Plainfield sand. The inflow
and outflow control systems on the soil column consisted of rows of porous ceramic
tubes with individual adjustable pressure controls. Uniform inflow and outflow
were achieved across the column, and v was maintained constant during each
experiment. An analysis of the transverse spread produced indicated that the
effect of apparatus-induced dispersion was less than 10%. D sub L (sq cm/min) was
linearly related to v(cm/min) (D sub L = 0.216v + 0.0032; sq r = 0.90). Slightly
larger D sub L was found in experiments with H2O replacing Cl than in experiments
with Cl replacing H2O. D sub L at the lowest v was 2 orders of magnitude greater
than D sub e. D sub T (sq cm/min) was essentially independent of v(d sub T =
0.0035V + 0.0031; sq r = 0.15) and was about 2 orders of magnitude greater than
D sub e at the lowest v studied. The spread of tracer at the outflow was inversely
proportional to v, and transverse dispersion had reduced the concentration peak of
the inflow by 84% at L = 23 cm and v = 0.01 cm/min. The ratio D sub L/D sub T
was proportional to v and ranged from about l(v = 0.01 cm/min) to about 20 (v =
0.28 cm/min).
78:02G-063
ANALYSIS OF A CAPILLARY HYSTERESIS MODEL BASED ON A ONE-VARIABLE DISTRIBUTION
FUNCTION,
Mualem, Y., and Morel-Seytoux, H.J.
Colorado State University, Fort Collins, Engineering Research Center.
Water-Resources Research, Vol. 14, No. 4, p 605-610, August, 1978. 11 fig, 12 ref.
Descriptors: *Hysteresis, *Soil moisture, *Model studies, *Mathematical models,
*Theoretical analysis, Porous media, Soil water movement, Model calibration,
Drying curves, Soil science.
49
-------
Parlange's model corresponds to a special case of Mualem's similarity hypothesis
f(psi sub w, psi sub d) = h(psi sub w)l(psi sub d) in which h(psi) is set at
unity for all psi values. Interpreted in terms of the soil water domain theory,
this assumption implies that the relative pore volume of the domains is distributed
uniformly in respect to the wetting radius (or to psi sub w). In this paper, the
proper mathematical equation was derived for calibrating the model from the
experimental main drying curve. The applicability of Parlange's model for the
soil water hysteresis was analyzed theoretically and extensively tested for
different types of porous media. Theoretical hysteretic curves derived by
direct implementation of Parlange's model were compared with experiments. These
comparisons showed that Parlange's model contradicts well-known properties of the
soil moisture characteristics. The good results reported by Parlange were not
obtained when actual measured curves of the hysteresis loop were used. Whether
the main branch of hysteresis for wetting or for drying is used in calibration,
badly distorted shapes of hysteresis curves are obtained. Parlange's suggestion
for calibrating the model on the basis of the main drying curve plus on6 addi-
tional point from the main wetting curve is considered too arbitrary to be
reliable.
78:02G-064
A MATHEMATICAL TREATMENT OF INFILTRATION FROM A LINE SOURCE INTO AN INCLINED
POROUS MEDIUM,
Zachmann, D.W.
Colorado State University, Fort Collins, Department of Mathematics.
Soil Science Society of America Journal, Vol. 42, No. 5, p 685-688, September-
October, 1978. 3 fig, 1 tab, 15 ref, 31 equ.
Descriptors: Infiltration, Mathematical studies, Porous media, Hydraulic
conductivity, Pressure head. Capillary action. Steady flow.
An exact mathematical solution was obtained for two-dimensional steady infiltration
from a line source into an inclined porous medium with an impermeable lower
boundary. Unsaturated hydraulic conductivity was assumed to be an exponential
function of pressure head. Equations for a stream function and the pressure head
were developed and stream lines and contours of constant pressure head were plotted
for a sandy soil and a clay soil using inclinations of 5 degrees and 20 degrees
from horizontal.
78:02G-065
SOLUTE TRAVEL-TIME ESTIMATES FOR TILE-DRAINED FIELDS: III. REMOVAL OF A
GEOTHERMAL BRINE SPILL FROM SOIL BY LEACHING,
Jury, W.A., and Weeks, L.V.
California University, Riverside, Department of Soil and Environmental Sciences.
Soil Science Society of America Journal, Vol. 42, No. 5, p 679-684, September-
October, 1978. 7 fig, 3 tab, 10 ref, 13 equ.
Descriptors: Ion exchange, Solutes, Travel time, Estimating, Brines, Leaching,
Reclamation, Tile drainage, Ion transport, Soil water movement.
The time required to leach a slug of saline, sodic geothermal brine from the
point of injection to the tile outlet of an artificially drained field was ;
calculated. Sprinkler, complete, and partial ponding leaching methods were com-
pared as a function of drain spacing and initial location of the spill. Calculated
results were presented as dimensionless parameters which scale the drainage system
dimensions and the soil water transport properties. Ponded leaching required
more water, but less time to leach brine out of the system for all situations
except where the brine spill occurs near the midpoint between tile lines. A
simple calculation was proposed to estimate the leaching fluid volume required
to remove excess Na(+) from the exchange complex. Good agreement was attained
between simulated and experimental results involving a laboratory s"oil column.
It was estimated that for fine-textured soils in the Imperial Valley of California
it may require up to 30 pore volumes of leaching fluid to replace Na(+) with
Ca(2+) if saturated gypsum solution is used in reclamation. Application time
per pore volume was calculated to be in excess of 1 year for all cases except
ponded leaching directly over a tile line.
50
-------
78:02G-066
DISPLACEMENT OF SOIL WATER BY SIMULATED RAINFALL,
Quisenberry, V.L., and Phillips, R.E.
Clemson University, South Carolina, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 5, p 675-679, September-
October, 1978. 3 fig, 3 tab, 15 ref, 1 equ.
Descriptors: Soil water movement, Simulated rainfall, Tracers, Soil water,
Moisture content, Laboratory tests.
Displacement of initial soil water by simulated rainfall was measured in
aggregates of Maury silt loam soil in columns in the laboratory and under field
conditions using tritiated water and/or Cl- as a tracer of added water. Dis-
placement values measured in aggregates were larger (53 to 85%) than those
measured under field conditions (7 to 56%). Percent displacement of initial
soil water in Galloway silt loam under field conditions were similar to those
of Maury, but were larger in Huntington silty clay loam than in Maury. Initial
soil water content of Maury soil did not appear to affect percent displacement.
Percent displacement in Maury soil increased as the depth of tillage increased.
78:02G-067
THE DEPENDENCE OF THE PARAMETERS IN THE GREEN AND AMPT INFILTRATION EQUATION ON
THE INITIAL WATER CONTENT IN DRAINING AND WETTING STATES,
Aggelides, S., and Youngs, E.G.
Cambridge University, Cambridge, England, Department of Applied Biology.
Water Resources Research, Vol. 14, No. 5, p 857-862, October, 1978. 10 fig,
1 tab, 22 ref, 18 equ.
Descriptors: Infiltration, Infiltration rates, Moisture content, Soil water
movement. Drying, Wetting, Hysteresis.
The parameters in the Green and Ampt infiltration equation were determined from
infiltration experiments in a sand column at various uniform initial water contents
in both draining and wetting states and were compared with various estimate ob-
tained from the soil water properties measured on the same experimental column.
The estimates of the soil water pressure head at the wetting front were generally
more negative than the values obtained from the directly measured parameters.
It was found that the calculated cumulative infiltration as a function of time
was fitted better by using Bouwer's crude "water entry" estimate than values
deduced by approximating Richards' flow equation.
78:02G-068
CLIMATE, SOIL, AND VEGETATION 3. A SIMPLIFIED MODEL OF SOIL MOISTURE MOVEMENT
IN THE LIQUID PHASE,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 722-730, October, 1978. 13 fig,
15 ref, 62 equ.
Descriptors: Soil water movement, Mathematical models, Porous media, Water
balance, Infiltration, Capillary action, Analytical techniques, Climatic data,
Soil properties. Vegetation.
Natural soil systems were modele'd one dimensionally from the surface to a
stationary water table by a homogeneous medium defined by three independent para-
meters. Four varieties of soil moisture movement were analyzed separately, and
their effects were linearly superimposed. Infiltration and exfiltration were des-
cribed by the Philip equation, which assumed the.medium to be effectively semi-
infinite and the internal soil moisture at the beginning of each storm and inter-
storm period was assumed to be uniform at its long-term space-time average. The
exfiltration equation was modified for the presence of natural vegetation through
the approximate introduction of a distributed sink representing the moisture
extraction by plant roots. Gravitational percolation to groundwater was assumed
to be steady throughout the rainy season at a rate determined by the long-term
space-time average soil moisture. Capillary rise from the water table was assumed
to be steady throughout the year and to take place to a dry surface.
51
-------
78:020-069
CLIMATE, SOIL, AND VEGETATION 6. DYNAMICS OF THE ANNUAL WATER BALANCE,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 749-764, October, 1978. 11 fig,
4 tab, 20 ref, 74 equ.
(See 78:02A-008)
78:02G-070
CLIMATE, SOIL, AND VEGETATION 7. A DERIVED DISTRIBUTION OF ANNUAL WATER YIELD,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 765-776, October, 1978. 10 fig,
3 tab, 13 ref, 35 equ.
(See 78:02A-007)
78:02G-071
A TWO-ELEMENT CERAMIC SENSOR FOR MATRIC POTENTIAL AND SALINITY MEASUREMENTS,
Scholl, D.G.
Forest Service, United States Department of Agriculture, Albuquerque, New Mexico,
Rocky Mountain Forest and Range Experimental Station.
Soil Science Society of America Journal, Vol. 42, No. 3, p 429-432, May-June,
1978. 3 fig, 6 ref.
Descriptors: *Soil moisture meters, *Saline soils, *Salinity, *Soil moisture,
*Salinity sensor, *Soil moisture sensor, *Coalmine spoil, *Salinity meter,
*Matric potential sensors, Salinity measurements.
A two-element ceramic sensor was developed to produce optimum electrical response
to both soil water matric potential and salinity. A spring-loaded housing was
developed for the elements for either drill-hole or pit-face placement. The
sensors were calibrated under various matric potential, salinity, and temperature
conditions. An initial field test with 72 sensors was conducted under irrigated
coal mine spoil conditions. Laboratory and field results indicated reasonable
instrument precision over a wide range of matric potential and salinity. The
correlation between sensor output and water content in the field was best where
the mean of several sensors was used.
78:020-072
DERIVATION OF EQUATIONS FOR VARIABLE RAINFALL INFILTRATION,
Morel-Seytoux, H.J.
Colorado State University, Fort Collins, Engineering Research Center.
Water Resources Research, .Vol. 14, No. 4, p 561-568, August, 1978. 7 fig, 2 tab,
9 ref, 41 equ, 1 append.
Descriptors: Infiltration, Infiltration rates, Rainfall, Ponding, Estimating
equations. Soil water movement, Mathematical models.
Formulae were derived for prediction of ponding time and cumulative infiltration
following ponding under a condition of piecewise variable and even intermittent
rainfall. The derivatives do not assume immediate saturation at the surface or
a piston displacement of air by water; they include the viscous flow of air. The
results were compared with experimental data of James and Larson (ASAE Winter
Meeting Paper, Chicago, Illinois, 1974) for two conditions: constant rainfall
and intermittent rainfall. The proposed formulae are simple to use, requiring
no complex solution of a partial or even an ordinary differential equation. The
numerical calculations presented in the paper were performed with a small pocket
calculator. The agreement with experimental data is good.
78:02G-073
EMPIRICAL EQUATIONS FOR SOME SOIL HYDRAULIC PROPERTIES,
Clapp, R.B., and Hornberger, G.M.
Virginia University, Charlottesville, Department of Environmental Sciences.
Water Resources Research, Vol. 14, No. 4, p 601-604, August, 1978. 2 fig, 2 tab,
15 ref, 7 equ.
52
-------
Descriptors: Soil physical properties, Hydraulic properties. Soil moisture,
Hydraulic conductivity, Infiltration, Air entrainment, Moisture tension, Equations.
The soil moisture characteristic may be modeled as a power curve combined with a
short parabolic.section near saturation to represent gradual air entry. This
two-part function—together with a power function relating soil moisture and
hydraulic conductivity—was used to derive a formula for the wetting front suction
required by the Green-Ampt equation. Representative parameters for the moisture
characteristic, the wetting front suction, and the sorptivity, a parameter in the
infiltration equation derived by Philip (Soil Sci., 84, 257-264, 1957), were
computed by using the desorption data of Holtan et al. (ARS 41-411, 609 pp., ARS,
Beltsville, Maryland, 1968). Average values of the parameters, and associated
standard deviations were calculated for 11 soil textural classes. The results
of this study indicate that the exponent of the moisture characteristic power
curve can be predicted reasonably well from soil texture and that gradual air entry
may have a considerable effect on a soil's wetting front suction.
78:02'G-074
CLIMATE, SOIL, AND VEGETATION 1. INTRODUCTION ,TO WATER BALANCE DYNAMICS,
Eagleson, P.S.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 705-712, October, 1978. 8 fig, 16 ref,
23 equ.
Descriptors: Water balance, Dynamics, Climatic data, Vegetation, Stochastic
processes, Probability, Soil moisture, Statistical methods, Soil-water-plant
relationships, Soil properties.
A statistical dynamic formulation of the vertical water budget at a land-atmosphere
interface was outlined. Physically based dynamic and conservation equations
expressed the infiltration, exfiltration, transpiration, percolation to groundwater
and capillary rise from the water table during rainstorms and interstorm periods
in terms of independent variables representing the precipitation, potential evapo-
transpiration, soil and vegetal properties, and water table elevation. Uncertainty
was introduced into these equations through the probability density function of the
independent climatic variables and yielded derived probability distributions of the
dependent water balance elements: surface runoff, evapotranspiration, and groundwater
runoff. The mean values of these quantities gave a long-term average water balance
which, to the first order, defined the annual water yield and water loss in terms
of the annual precipitation and potential evapotranspiration and in terms of physical
parameters of the soil, vegetation, climate, and water table. This analytical
framework provides physical insight into the dynamic coupling of climate-soil-
vegetation systems.
78:020-075
ERRORS IN GAMMA HRAY MEASUREMENTS OF WATER CONTENT AND BULK DENSITY IN NONUNIFORM
SOILS,
Nofziger, D.L.
Oklahoma State University, Stillwater, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 6, p 845-850, November-
December, 1978. 7 fig, 1 tab, 6 ref, 7 equ. ,
Descriptors: Soil moisture, Soil water. Moisture content, Bulk density, Measurement,
Stratification, Infiltration, Attenuation, Gamma rays, Clays.
Recent experimental study of freezing soils has shown gamma-ray measurements of
water content and bulk density are in error when the water content and bulk density
are not uniform throughout the gamma-ray beam. Many gamma-ray measurements involve
nonuniform soils. This study was conducted to determine the magnitude of errors
due to nonuniform bulk density and water content. Errors in gamma-ray water content
and bulk density were determined for soil-water systems with linear and step-function
changes in water content and bulk density and for measurements of water absorption
by a nonswelling porous medium. Both single-energy and dual-energy gamma-ray systems
were analyzed. The results showed that large errors in water content and bulk
density determined by dual-energy gamma-ray measurements can occur for highly
stratified soils and relatively small errors occur if the bulk density and water
content change linearly in the collimated beam. Both single- and dual-energy systems
53
-------
accurately measured the average water content in the collimated beam when the
bulk density of the soil was constant. However, the average water content
in the beam did not always represent the water content at the middle of the
collimated beam and the middle of the preset time period. Errors due to non-
uniform soil can be evaluated using the equations and graphs presented.
78:02G-076
SEASONAL WATER USE BY WINTER WHEAT GROWN UNDER SHALLOW WATER TABLE CONDITIONS,
Saini, B.C., and Ghildyal, B.P.
G.B. Pant University of Agriculture and Technology, Pantnagar, Distr. Nainital,
India.
Agricultural Water Management, Vol. 1, No. 3, p 263-276, November, 1978. 10 fig,
1 tab, 27 ref.
Descriptors: Water requirements, Soil water movement, Shallow water, Moisture
tension, Water management (applied), Moisture content, Root zone, Tensiometers,
Moisture deficit, Wheat.
Techniques for estimating seasonal water use from soil profile water depletion
frequently do not account for flux below the root zone. A method using tensio-
meters for obtaining evapotranspiration losses from the root zone and water
movement below it was discussed. Soil water flux below the root zone was
approached by a sequence of pseudo steady state solutions of the flow equation.
Upward soil water flux contributed 36 to 73% to the total water requirement of
winter wheat (Triticum aestivum L.) whereas soil water depletion accounted for
11 to 19% only. Water use efficiency with one irrigation during an early
stage of plant development was greater than with no or three irrigations. This
was the result of both decrease of resistance due to soil moistening and better
root development. Tensiometer readings were also interpreted to estimate root
zones, water table depths and soil moisture contents. Methods described in this
paper can be used in determining seasonal water use by growing crops, replacing
or supplementing lysimeter or meteorology approaches to this problem.
78:02G-077
CONVECTIVE TRANSPORT OF SOLUTES BY STEADY FLOWS 1. GENERAL THEORY,
Raats, P.A.C.
Institute for Soil Fertility, Oosterweg 92, Haren, The Netherlands.
Agricultural Water Management, Vol. 1, No. 3, p 201-218, November, 1978. 3 fig,
1 tab, 10 ref, 64 equ.
Descriptors: Soil water movement, Solutes, Convection, Steady flow, Theoretical
analysis, Anisotropy, Water quality, Travel time, Leaching, Drainage.
A comprehensive theory describing convective transport of solutes was presented.
The time required for a parcel of water to move from one point to another along
a streamline was determined, and this basic information was then used to describe
collections of parcels of water forming a surface. Input-output relationships
were determined in terms of the distribution of the solute over the inflow and out-
flow surfaces. A simple geometric transformation was used to extend the theory
to anisotropic media.
78:02G-078
CONVECTIVE TRANSPORT OF SOLUTES BY STEADY FLOWS II. SPECIFIC FLOW PROBLEMS,
Raats, P.A.C.
Institute for Soil Fertility, Oosterweg 92, Haren, The Netherlands.
Agricultural Water Management, Vol. 1, No. 3, p 219-232, November, 1978. 5 fig,
31 ref, 27 equ.
Descriptors: Soil water movement, Solutes, Convection, Steady flow, Drainage,
Leaching, Flow characteristics, Flow system, Travel time.
A comprehensive .theory describing convective transport of solutes was presented
in Part I (Agric. Water Manage., 1:201-218). In this paper, the general theory
was applied to specific flow problems. The relatively simple problem of leaching
to drains and ditches induced by an input distributed uniformly over the surface
was discussed in detail. It was shown that if the ratio of the halfspacing between
the drains or ditches and the depth to the impermeable layer is larger than about
five, density distribution is approximately exponential. The general theory was
also used to evaluate the literature on many other problems.
54
-------
78:02G-079
SOIL WATER RETENTION AS RELATED TO PARTICLE SIZE IN SELECTED SANDS AND LOAMY
SANDS,
Rivers, E.D., and Shipp, R.F.
Bureau of Reclamation, Bismark, North Dakota, Missouri-Souris Projects Office.
Soil Science, Vol. 126, No. 2, p 94-100, August, 1978. 1 fig, 3 tab, 7 ref.
Descriptors: *Soil water, *Particle size, *Soil-texture, *North Dakota, *Soil
water retention, *Glacial Lake Souris basin (ND), Retention, Field capacity,
Soils, Loam.
Sands and loamy sand within the Glacial Lake Souris basin in North Dakota vary
considerably Jroni one area to another in their particle size distribution. The
objective was to relate water retention of these sandy soil textural classes to
particle size percentage. Water retention percentages, on an over-dry basis,
were determined for samples at field capacity under field conditions and also at
1/10-, 1/15-, and 1/20-bar soil water suction for air-dried, less than 2-mm
samples in conventional porous ceramic plate-pressure pot equipment. No single
soil water suction produced water retention values adequately representing
field capacity for all textures. In most instances, the percentage of very fine
sand alone and in combinations with the percentages of silt and clay were corre-
lated significantly with soil water values.
78:02G-080
THE DEPENDENT DOMAIN THEORY APPLIED TO SCANNING CURVES OF ANY ORDER IN HYSTERETIC
SOIL WATER RELATIONSHIPS,
Poulovassilis, A., and El-Ghamry, W.M.
Agricultural Research Council, Cambridge, England, Unit of Soil Physics.
Soil Science, Vol. 126, No. 1, p 1-8, July, 1978. 9 fig, 13 ref.
Descriptors: *Soil water, *Hysteresis, *Model studies, Mathematical models,
Wetting, Drying, Moisture content, Pressure, Pore pressure, Theoretical analysis.
The dependent domain theory was extended to cover scanning curves of any order
in the hysteretic relationship between soil water content, theta, and pressure,
P. It was argued that if the distribution function1, F, for the domains depends
on the most recent reversal value of P, than F depends also on all the previous .
reversalt values. Experimental primary scanning curves and scanning curves of
the first, second, and third orders of the relationship between theta and P for
a sand were presented, and the hysteretic behavior of this experimental relation-
ship was compared with that predicted by the dependent domain theory.
78:02G-081
PREDICTED AND MEASURED DRAINABLE POROSITIES FOR FIELD SOILS,
Skaggs, R.W., Wells, L.G., and Ghate, S.R.
North Carolina State University, Raleigh, Department of Biological and Agricultural
Engineering.
Transactions of the American Society of Agricultural Engineering, Vol. 21, No. 3,
p 522-528, May-June, 1978. 8 fig, 3 tab, 12 ref.
Descriptors: *Porosity, *Soil properties, *Drainage, *Model studies, *Drainable
porosities. Laboratory tests, Soil water movement, Water table, Soil science,
Soils.
Experiments were conducted on large field cores to determine the relationship
between drainage volume and water table depth for five soils. The measured
drainage volumes were less than predicted from the soil water characteristics
for three soils, but were in good agreement for the other two. Drainable poro-
sities were calculated from both theoretical and experimental drainage volume-
water table depth relationships by assuming that the unsaturated zone is
essentially "drained to equilibrium" with the water table. The experimental
drainable porosities thus obtained were less than predicted. Drainable porosities
for drainage to two-dimensions were calculated from experimental results for
one dimension by assuming an elliptical water table profile. These results gave
nearly constant drainable porosities for the layered soils and a variable drainable
porosity for Wagram, a homogeneous, sandy soil.
55
-------
78:020-082
TIME OF SPREAD RELATIONSHIP IN IRRIGATION CHECK BASINS,
Sharma, T.C.
Guelph University, Ontario, Canada.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 3, p 505-509, June 20, 1978. 3 fig, 4 tab, 5 ref, 10 equ.
Descriptors: Basins, Irrigation, Dimensional analysis, Time, Infiltration,
Estimating, Estimating equations.
Time of spread of water in a check basin is of vital importance for designing
efficient check basin irrigation system. The analytical solutions for determina-
tion of time of spread tend to be quite complex and impractical due to the un-
steady spatially varied nature of flow on nearly zero slopes of the land. In
this study, the technique of dimensional analysis was used to derive time of
spread relationships in check basins.
78:02G-083
INTAKE CHARACTERISTICS OF IRRIGATION FURROWS.
Fangmeier, D.D., and Ramsey, M.K.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 4, p 696-700, 705, August 20, 1978. 3 fig, 3 tab, 5 ref, 19 equ.
Descriptors: Infiltration, Intakes, Furrow irrigation, Infiltration rates,
Furrows, Estimating equations.
Seven irrigations were conducted on precision field furrows. Water volume balances
were used to calculate infiltration and intake functions. The Philip equation
provided a slightly better estimate of infiltration than the Kostiakov equation,
but the constants in the Philip equation were more difficult to obtain. The
intake rate appeared to be linearly related to the wetted perimeter for the
irrigations conducted.
78:02G-084
VARIABILITY OF SOIL WATER RETENTION CURVES AND PREDICTED HYDRAULIC CONDUCTIVITIES
ON A SMALL PLOT,
Cameron, D.R.
Research Station, Research Branch, Agriculture Canada, Swift Current, Saskatchewan
S9H 3X2.
Soil Science, Vol. 126, No. 6, p 364-371, December, 1978. 3 fig, 4 tab, 19 ref.
Descriptors: Soil moisture. Soil water, Moisture content, Moisture tension,
Hydraulic conductivity, Drying, Wetting, Retention, Soil water movement.
Soil water retention curves were measured on cores taken from five sites at six
depths in a Bainsville clay loam soil. There were differences in both the shape
and magnitude of the average moisture characteristic curves from one location to
another in the 225 sq m plot. Coefficients of variation ranged from 4.2 to 13%
in the surface layers and from 2.4 to 6.5% in the deeper layers. There were no
consistent trends in variability with respect to tensions from 0 to -500 cm H2O.
Predicted and measured hydraulic conductivity functions were variable, often
showing a 100-fold difference at a given water content. The measured K functions
were steeper than those predicted, and the match between them was considered
reasonable only at the lower water contents.
78:02G-085
THEORY AND SYSTEM OF AUTOMATIC DETERMINATION OF SOIL MOISTURE CHARACTERISTICS
AND UNSATURATED HYDRAULIC CONDUCTIVITIES,
Boels, D., Van Gils, J.B.H.M., Veerman, G.J., and Wit, K.E.
Institute for Land and Water Management Research (ICW), P.O. Box 35, Wageningen,
The Netherlands.
Soil Science, Vol. 126, No. 4, p 191-199, October, 1978. 6 fig, 3 tab, 24 ref,
11 equ.
56
-------
Descriptors: Soil moisture, Moisture content, Water pressure, Soil water. Soil
water movement, Unsaturated flow, Hydraulic conductivity, Infiltration, Core.
The moisture characteristic and the unsaturated hydraulic conductivity were cal-
culated from the measured water pressures at different depths in a soil core and
the weights during evaporation at the'top of the core. The measured water pres-
sure was ass'umed to represent the mean pressure in a layer of a certain thickness,
and the moisture characteristic was assumed to be described with sufficient ac-
curacy by a polynom. The tangent of the polynom in each pressure interval was
solved from a set of equations. The water pressure at different depths was
measured with one pressure transducer, connected with a scannivalve; the weight
was measured with a strain-gauge load cell; and the data were recorded on a
magnetic cassette tape. The recorded data were processed by a computer and
stored on a magnetic disc. When the saturated conductivity was relatively high,
a steady-state infiltration method was applied to determine the unsaturated
hydraulic conductivity at high water contents.
78:02G-086
TRANSPORT OF REACTIVE SOLUTES DURING TRANSIENT UNSATURATED WATER FLOW IN
MULTILAYEESD SOILS,
Selim, H.M.
Louisiana State University, Baton Rouge, Department of Agronomy, Louisiana
Agricultural Experiment Station.
Soil Science, Vol. 126, No. 3, p 127-135, September, 1978. 10 fig, 14 ref,
19 equ.
Descriptors: Soil water movement, Soil water, Unsaturated flow, Unsteady flow,
Infiltration, Adsorption, Mathematical models.
A numerical model was developed to predict water and reactive solute transport
through water-unsaturated, multilayered soils. An explicit-implicit finite
difference approximation method was used to solve the water and solute transport
equations simultaneously. Calculated results were presented for two-and three-
layered soils during water infiltration and redistribution. Linear and nonlinear
equilibrium adsorption, first-order kinetic reaction, and irreversible kinetic
reaction were used to describe solute adsorption in individual soil layers. It
was found that, for all adsorption mechanisms considered, concentration distri-
bution during infiltration and redistribution was significantly influenced by
the order in which the soil layers were stratified.
57
-------
SECTION VIII
WATER CYCLE
LAKES (GROUP 02H)
78:02H-001
FIELD INVESTIGATION OF SELECTIVE WITHDRAWAL,
Ivey, G., and Imberger, J.
California University, Berkeley, Department of Mechanical Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
104, No. HY9, p 1225-1237, September, 1978. 4 fig, 3 tab, 6 ref, 5 equ-, .2 append.
Descriptors: Reservoirs, Reservoir operation, Withdrawal, Reservoir releases,
Diffusion, Viscous flow, Buoyancy, Australia.
An integral part of a reservoir management scheme is the specification of the
nature and extent of the flow within the reservoir induced by withdrawing water
at an outlet. The steady-state thickness and extent of the withdrawal layer
were examined in this paper. Existing theory indicated that, throughout the
study period, the withdrawal layer was in a steady state in the regime governed
by a balance between buoyancy and viscous forces. A natural salt tracer in the
water enables estimates of the mean withdrawal layer thickness over a 10-km
(6.2-mile) length upstream from the sink for two different time periods. To
achieve good agreement between theoretical predictions and field measurements,
it was necessary to postulate transport coefficients of momentum approximately
ten times the molecular value. Comparisons with model simulations over the same
time period suggested an effective average Prandtl number of 20 in the hypolimnion
78:02H-002
ON THERMAL STRATIFICATION IN RESERVOIRS DURING THE WINTER SEASON,
Rahman, M.
National Research Council of Canada, Ottawa, Ontario, Division of Mechanical
Engineering.
Water Resources Research, Vol. 14, No. 2, p 377-380, April, 1978. 2 fig, 5 ref.
Descriptors: *Thermal stratification, *Reservoirs, *Seasonal, *Diffusivity,
*Boundary processes, *Temperature profile, Numerical analyses, Heat flux, Initial
temperature, Ice.
A one-dimensional mathematical model describing the thermal structure in stratifie
reservoirs during the winter season was considered. With the help of this model,
an attempt was made to clarify some of the physical factors which strongly in-
fluence the temperature profiles in reservoirs. It has been observed that there
are many factors which influence the shape of the vertical temperature distribu-
tion, namely, the profile at the time of ice formation, the heat exchange by
diffusion in the water mass, the heat exchange due to inflow and outflow of water
in reservoirs, etc. This model accounts for a qualitative assessment of the
possible effects of diffusivity and the initial shape of the temperature profiles
on the variation of the vertical temperature distribution.
58
-------
SECTION IX
WATER CYCLE
WATER AND PLANTS (GROUP 021)
78:021-001
IRRIGATION EFFECTS ON VEGETATIVE AND REPRODUCTIVE DEVELOPMENT OF THREE SOYBEAN
CULTIVARS,
Ashley, D.A., and Ethridge, W.J.
Goergia University, Athens, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 3, p 467-471, May-June,
1978. 6 tab, 13 ref.
Descriptors: Soybeans, Supplemental irrigation, Growth stages, Plant growth,
Irrigation effects.
This field experiment considered four moisture regimes—no irrigation, full
season irrigation, irrigation starting at bloom stage, and irrigation starting
at pod fill stage-on three soybean cultivars, "Ransom", "Hamptom 266A", and
"Coker 102". Data were collected for seed yield, pod number and dry weight,
dry weight of vegetative components during reproductive development and seasonal
soil moisture status. The soil was a sandy loam. Full season and bloom stage
irrigation treatments produced higher yields than the unirrigated check except
for Hamptom 266A in 1974. Yields from plants receiving the podfill stage
irrigation treatment were higher than the unirrigated check in drier seasons of
1972 and 1973 but not in 1974. Irrigation beginning at pod fill produced yields
equal to the full season and bloom stage treatments in some cases and somewhat
lower yields in other cases. Water application prior to blooming greatly in-
creased vegetative dry weight, number, and dry weight of pods. Beginning irri-
gation during reproductive development had little effect on vegetative dry
weight, but usually resulted in a greater number of pods late in the season
than the unirrigated check. Higher yields and greater response to irrigation
were obtained from shorter Ransom plants than the other two cultivars.
78:021-002
IRRIGATION TIMING—ITS INFLUENCE ON THE EFFECTS OF SALINITY AND WATERLOGGING
STRESSES IN TOBACCO PLANTS,
West, D.W., and Black, J.D.F.
Horticultural Research Institute, Victoria, Australia, Department of Agriculture.
Soil Science, Vol. 125, No. 6, p 367-376, June, 1978. 1 fig, 4 tab, 33 ref.
Descriptors: Saline water. Water quality, Sodium chloride, Drainage, Soil-water-
plant relationships, Oxygen, Irrigation, Diffusion, Growth chambers, Tobacco.
The effects of irrigation timing on the interaction between salinity and water-
logging, and changes in the oxygen status in the root zone of a heavy soil under
tobacco plants irrigated with drip system were studied. Water uptake was
significantly reduced by the presence of NaCl in the root zone irrespective of
irrigation and drainage treatment. Leaf chloride in all nonsalinized treatments
was significantly lower than in all salinized treatments. Both day and night
waterlogged saline treatments contained significantly higher leaf chloride than
the nonwaterlogged saline treatment. The night-waterlogged saline treatment
contained significantly lower leaf chloride than the day-waterlogged saline
treatment. Similar trend to high Cl(-) content with day waterlogging was present
with petioles and stems. Root Cl(--} concentrations were relatively low irrespective
of treatment. Leaf sodium concentrations were relatively low irrespective of
treatment. Leaf sodium concentrations of day- and night-waterlogged saline
treatments were significantly higher than all other treatments, and the day-
waterlogged salinized plants had significantly higher leaf Nat than the night-
waterlogged salinized plants. The results suggests that plants in a soil with
some chance of being waterlogged in the root zone and with NaCl present in the
root zone would benefit from being irrigated at night rather than during the day.
59
-------
78:021-003
CROP WATER REQUIREMENT IN RELATION TO CLIMATE AND SOIL,
Shalhevet, J-, and Bielorai, H.
Institute of Soils and Water, Bet Dagan, Israel, ARO-The Volcani Center.
Soil Science, Vol. 125, No. 4, p 240-247, April, 1978. 2 fig, 4 tab, 22 ref.
Descriptors: Water requirements, Yield equation. Climatic data, Soil properties,
Cotton, Sorghum, Grapefruit, Evapotranspiration, Evaporation, Pans, Correlation
analysis.
The effect of variation in climate and soil on the production function of water
for the yield of cotton, sorghum, and grapefruit was analyzed to determine the
transferability of water requirement information, accumulated in Israel, to
other regions of the world. A model giving relative yield (Y) as a linear
function of relative evapotranspiration (EK/EQ) for all climatic regions together
was compared with regional relationships of Y to net water application. Y is the
ratio of a treatment yield to the maximum yield obtained in an experiment; Et
and E0 are the cumulative seasonal evapotranspiration, including a small drainage
component, and pan evaporation, respectively. The correlation coefficients were
high for field crops but smaller for citrus. About 90 percent of the variability
in yield of field crops were attributed to differences in potential evapotranspira-
tion and in irrigation amounts. No effect was found of variation in soil on crop
yield due to the rather uniform water-storage capacity of soils of varying texture.
It was proposed that the production functions obtained in Israel may be used in
regions with similar climatic characteristics for a wide range of soils after
accounting for climatic variations through pan evaporation estimates.
78:021-004
SIMULATED PLOW THROUGH THE ROOT XYLEM,
Busscher, W.J., and Fritton, D.D.
Rutgers University, New Brunswick, New Jersey, Department of Soils and Crops.
Soil Science, Vol. 125, No. 1, p 1-6, January, 1978. 5 fig, 14 ref, 5 equ.
Descriptors: Xylem, Root systems, Flow resistance, Flow rates, Simulation
analysis, Model studies, Water pressure, Evapotranspiration.
Flow through the xylem of a complex root system is simulated to measure xylem
resistance to water flow, and to determine whether or not this resistance
is significant. Equations are set up that model xylem water flow as if it were
flow through thin tubes. The root characteristics needed to solve these equations
are obtained from an earlier work. Xylem water flow is first considered foz a
single main root and its laterals. It decreases with age of the root or in-
crease of root length, and it increases with the addition of laterals. The
advantage of an increasing number of main roots is also shown. Finally, flow
through the plant crown is compared to Thornthwaite and Blaney-Criddle evapo-
transpirational estimates. Less than 10 millibars of water pressure is needed
to overcome xylem resistance, and, therefore, the resistance is considered
negligible.
78:021-005
RELATIONSHIP BETWEEN SOIL TEST AND SMALL GRAIN RESPONSE TO P FERTILIZATION IN
FIELD EXPERIMENTS,
Fixen, P.E., and Carson, P.L.
South Dakota State University, Brookings, Department of Plant Science.
Agronomy Journal, Vol. 70, No. 5, p 838-844, September-October, 1978. 3 fig, 8 tab/
35 ref.
Descriptors: Soil tests, Fertilization, Phosphorus, Grains (crops), 'Correlation
analysis, Regression analysis, Climatic data, Soil properties, Crop response,
Organic matter.
Yield data from 74 small grain field experiments over a 13-year period were used
to evaluate the relationship between various soil tests and P response. The soil
tests examined in this study were the Bray 1 (soil to solution ratio of 1:7, 1:10,
1:20, and 1:50), Olsen P, and P sorption index of Bache and Williams. The crop
species included were Triticum aestivum L., Hordeum vulgare L., and Avena sativa
L. The highest correlation between soil test value and yield response P
60
-------
2
fertilization was found with the Bray 1, 1:50 (r = 0.41). An additional 23%
of the yield response variation could be explained by including six
additional variables in a multiple regression analysis employing dummy
variables. The r value between P sorption index and yield response on alkaline
soils was -0.70 but was near zero for. acid soils. Differences were also noted
in degree of response between parent materials and crop species. Organic
matter content appeared to influence response on some soils.
78:021-006
ALFALFA WATER USE AND PRODUCTION ON DRYLAND AND IRRIGATED SANDY LOAM,
Bauder, J.W., Bauer, A., Ramirez, J.M., and Cassel, D.K.
North Dakota State University, Fargo, Department of Soils.
Agronomy Journal, Vol. 70, No. 1, p 95-99, January-February, 1978. 2 fig, 3 tab,
12 ref.
Descriptors: Alfalfa, Irrigation effects, Soil-water-plant relationships.
Moisture stress, Evapotranspiration, Fertilization, Crop production, Great Plains,
Correlation analysis.
This study was carried out on a Maddock sandy loam soil, a member of the sandy,
mixed frigid Udorthentic Haploboralls. Four irrigation levels, ranging from
dryland to excessive irrigation, were established as whole plots in a randomized
block, split plot design. Eight different fertilizer treatments of P, K, and S
were applied to split plots during the 1st year of the study. Under a three
harvest per season management system dry matter yield was significantly affected
by harvest number and irrigation treatment each year. Within the dryland and
deficient irrigation treatment by year, yields decreased with each cutting; with
optimum and excessive irrigation, yields varied inconsistantly with cutting,
yields increased 14 to 330% over dryland by increasing irrigation applica-
tions. When plant water stress existed throughout the growing season, relative
yield correlated with relative evapotranspiration in a near perfect, linear
manner. Under nonstress conditions, irrigation, growing season precipitation,
and soil water depletion required consideration to attain nearly perfect correla-
tion of relative yield with relative evapotranspiration. The results of this
study indicated that under plant water stress conditions, alfalfa dry matter
yield is a linear function of plant water use.
78:021-007
NUTRIENT UPTAKE BY GRASS AND LEACHING LOSSES FROM SOLUBLE AND S-COATED UREA AND
KC1,
Allen, S.E., Terman, G.L., and Kennedy, H.G.
National Fertilizer Development Center, TVA, Muscle Shoals, Alabama, Soils and
Fertilizer Research Branch.
Agronomy Journal, Vol. 70, No. 2, p 264-268, March-April, 1978. 4 fig, 4 tab,
6 ref.
Descriptors: Leaching, Fescues, Sudangrass, Nutrients, Fertilizers, Nitrogen,
Potassium, Crop response, Lysimeters, Ureas.
Slow-release fertilizers should provide for more efficient nutrient use by the
crop as well as reduce leaching losses. This study was conducted to measure
crop response to N or K in uncoated urea, ammonium nitrate, S-coated urea, and
S-coated KC1 and to relate leaching losses to N03 - N and cations. In one
series, granular N sources to supply 200 or 400 kg of N/surface ha were mixed with
the upper 20 cm of a 1:1 mixture of Norfolk si (Typic Paleudult) and builders sand
contained in 15 cm by'120 cm columns. A second series was similarly fertilized with
K sources to supply 100 or 200 kg of K/surface ha.
78:021-008
ROOT-SINK DESCRIPTIONS OF WATER SUPPLY TO DRYLAND WHEAT,
Rickman, R.W., Allmaras, R.R., and Ramig, R.E.
Oregon State University, Pendleton, Columbia Plateau Conservation Research Center.
Agronomy Journal, Vol. 70, No. 5, p 723-728, September-October, 1978. 11 fig,
13 ref, 4 equ.
61
-------
Descriptors: Moisture uptake, Wheat, Moisture tension, Soil water movement, Soil
profiles, Root distribution, Dry farming, Soil-water-plant relationships, Sink,
Hydraulic conductivity.
Soil water content changes were supplemented with calculations of water flow
between soil layers to provide an improved description of water uptake by dry-
land wheat (Triticum aestivum L.). Water content changes were estimated from
neutron meter measurements. Soil water flux was estimated from field measure-
ments of both hydraulic conductivity and hydraulic head gradients; unsaturated
conductivity beyond the range of field measurement was calculated with the pore
interaction model of Marshall matched to field measured values at 250 mb.
Seasonal water-uptake patterns, determined by the root-sink description, differed
from those shown by only water content measurements. Peak water-use rates did
not coincide with maximum leaf area index, but coincided with the period from
heading to completed head extension. Water flux in the profile was important for
supplying water during grain filling and was critical in this layered soil,
which restricted rooting to depths less than 150 cm.
78:021-009
FERTILIZER PLACEMENT EFFECTS ON SOYBEAN SEED YIELD, N2 FIXATION, AND 33P UPTAKE,
Ham, G.E., and Caldwell, A.C.
Minnesota University, St. Paul, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 5, p 779-783, September-October, 1978. 2 fig,
4 tab, 20 ref.
Descriptors: Nitrogen fixation, Soybeans, Phosphorus, Radioisotopes, Fertilizers,
Ureas, Seeds, Productivity.
This study was planned to evaluate the efficiency of P fertilizer utilization
by field-grown soybeans with different fertilizer placements using 33P labelled
fertilizer (35 kg P/ha) on a Waukegan silt loam soil (Typic Hapludoll) low in
plant available N and P. In addition, urea (30 kg N/ha) labelled with 15N was
added to measure the effect of P fertilizer placement on N uptake and N2 fixation
using the "A" value concept concerning the measurements of available soil nutrients
developed by Fried and Dean (1952). Soybean seed yield and total P uptake were
increased significantly by adding P fertilizer with no differences among the
fertilizer placements (seed yield ranged from 3,811 to 4,035 kg/ha compared to
3,200 kg/ha for the control). The 33P labelled fertilizer provided a direct,
quantitative measure of the efficiency of plant use of the added P and provided
a basis of evaluating the fertilizer placements without the hazards associated
with 33P over the 149-day experiment. The "A" value concept provided a reliable
estimate of N2 fixation which agreed with Kjeldahl measurements.
78:021-010
DIFFERENTIAL RESPONSE OF SOYBEAN VARIETIES TO SOIL CADMIUM,
Boggess, S.F., Willavize, S., and Koeppe, D.E.
Illinois University, Urbana, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 5, p 756-760, September-October, 1978. 1 fig, 5 tab,
30 ref.
Descriptors: Cadmium, Toxicity, Soybeans, Varieties, Crop response, Sewage sludge,
Soil amendments, Trace elements.
This paper presents the results of a comprehensive survey of the Cd uptake and
effect by a number of the prominent soybean (Glycine max (L.) Merrill) varieties
grown on several CdC12 or sewage slude-amended soils in the glasshouse'. In all
varieties, Cd toxicity symptoms appeared as a continuum from slight effects ob-
served as a red, red-brown, or purple coloration at the junction of the leaf
blade and petiole, to severe leaf curling and extensive reddening of the leaf
veins, chlorosis, and finally a brittle condition followed by abscission of the
leaves. All varieties showed increased shoot Cd concentration and decreased dry
weight in response to soil CdC12, but varietal differences in the severity of
these Cd effects were observed. Further analysis of data for Cd susceptibility
suggested that, of the soybean varieties tested on CdC12-amended soils, Dunfield,
Harosoy, Arksoy, Dare, Flambeau, and Scioto were generally the most susceptible
while Clark, Mandarin, Mukden, Jackson, and Lee were consistently ranked as less
susceptible.
62
-------
78:021-011
SEEDLING EMERGENCE AS RELATED TO TEMPERATURE AND MOISTURE TENSION,
Wright, D.L., Blaser, R.E., and Woodruff, J.M,
Florida University, Quincy.
Agronomy/Journal, Vol. 70, No. 5, p 709-712, September-October, 1978. 1 fig,
1 tab, 16 ref.
Descriptors; Erosion control, Grasses, Legumes, Highway beautification,
Germination, Seeds, Moisture tension, Temperature.
To aid in selection of species for mixtures of seed for controlling erosion on
newly constructed highway slopes, an experiment was designed to determine total
emergence and rates of emergence of several grass and legume species and cultivars
under various soil moisture and temperature regimes. The experimental observa-
tion suggested that the aggressive species of annual and perennial ryegrass,
German millet, redtop, weeping lovegrass, and Abruzzi rye compete strongly with
slower developing perennial grasses and legumes when seeded in the appropriate
season. It was also observed that successful establishment of the intermediate
species such as bluegrass, crownvetch, creeping red fescue, and Kentucky 31 tall
fescue depends on cool temperatures and high moisture availability. Nonaggressive
species of crownvetch and sericea also required high moisture and cool temperature,
whereas common bermudagrass needed high moisture and warm temperatures. It was
concluded that modification of seed mixtures should depend on the season of
seeding and the type of vegetation, desired, and that lower rates of agressive
species should be used while seeding mixtures of aggressive species with slow-
developing species when conditions favor rapid emergence and growth for both.
78:021-012
DIFFERENCES AMONG GENOTYPES OF CORN IN THE KINETICS OF P UPTAKE,
Nielsen, N.E., and Barber, S.A.
The Royal Veterinary and Agricultural University, Copenhagen, Denmark.
Agronomy Journal, Vol. 70, No. 5, p 695-698, September-October, 1978. 6 tab,
23 ref, 1 equ.
Descriptors: Corn (field), Phosphorus, Simulation analysis, Soil properties,
Root systems, Correlation analysis.
Many plant species utilize fertilizer of soil P inefficiently. A survey of 12
inbred corn genotypes (Zea mays L.) grown in water culture indicated a 1.8 to 3.3-
fold variation in root weight, root length per unit of plant weight, root length
per unit of root weight, and maximal net P influx. Some aspects of the role of
genetics were elucidated by comparing the P absorption parameters of five inbreds
with those of four single-cross hybrids made from these inbreds. Five single
crosses were grown at low and high P levels in the field on a Raub silt loam
(Aquic Argiudoll) to test the significance of the measured root parameters on P
uptake. Plants were harvested 22, 38 and 51 days after planting. Phosphorus
uptake was also simulated by a model using soil and plant root parameters related
to P uptake. The correlation between predicted and observed P uptake was r2 =
0.90 for the 22 to 38-day time interval and r2 =0.98 for the 22 to 51-day time
interval. Hence, observed differences among corn single crosses in their plant
root parameters were reflected in their P uptake when grown in the field.
78:021-013
TEMPERATURE DEPENDENCE OF WATER UPTAKE BY PLANT ROOTS,
Dalton, F.N., and Gardner, W.R.
Wisconsin University, Madison, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 3, p 404-406, May-June, 1978. 4 fig, 1 tab, 11 ref,
13 equ.
Descriptors: Moisture uptake, Root systems, Temperature, Solutes, Kinetics,
Diffusivity.
The transport of water through root membranes is described in terms of equations
which couple water and solute transport. The solute transport equation includes
active as well as passive uptake. Temperature effects are manifested in the
viscosity of water, the osmotic permeability coefficient of the membranes, and the
rate constant for the active solute uptake. From standard reaction rate kinetics,
reasonable estimates of the temperature coefficients of these three processes are made.
63
-------
A general equation for the effect of temperature on the uptake rate for a given
driving force is derived. This difference in flux between live and dead roots
is adequately described by the model, indicating the significance of the active
component of the uptake process.
78:021-014
INFLUENCE OP K ON THE UPTAKE, TRANSLOCATION, AND REDUCTION OF NITRATE BY BARLEY
SEEDLINGS,
Blevins, D.G., Hiatt, A.J., Lowe, R.H., and Leggett, J.E.
Kentucky University, Lexington, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 3, p 393-396, May-June, 1978. 5 fig, 1 tab, 17 ref-
Descriptors: Nitrates, Translocation, Reduction (chemical), Barley, Organic
acids, Metabolism, Calcium, Potassium, Growth chambers.
The purpose of this study was to determine the influence of K or Ca on nitrate
uptake, translocation, and reduction in barley seedlings. Six-day-old barley
seedlings were grown for 2 to 36 hours in solutions of 1.0 meg/liter KN03 or Ca
(NO3)2, each containing 0.4 meq/liter of CaS04. Experiments were conducted in a
growth chamber at 27 C with a photosynthetic irradiance of 5.3 mW times cm-3.
Seedlings treated with Ca(N03)2 (low K) had lower levels of nitrate uptake, nitrate
reductase activity, and lower organic acid concentrations than seedlings treated
with 1 mM KN03. The solution pH and the expressed sap pH of roots and shoots of
the low K seedlings increased during the experiment. The shoots of the low-K
seedlings had much lower nitrate concentrations and lower levels of nitrate reduc-
tase activity than the roots, suggesting that K plays a major role in nitrate
translocation. These results support the hypothesis that potassium malate is
cycled from the tops to the roots where decarboxylation occurs, providing a source
of HCO3(-) for exchange with NO3(-) during absorption.
78:021-015
RESPONSES OF STOMATA AND WATER, OSMOTIC, AND TURGOR POTENTIALS OF JOJOBA TO WATER
AND SALT STRESS,
Adams, J.A., Bingham, F.T., Kaufmann, M.R., Hoffman, G.J., and Yermanos, D.M.
California University, Riverside, Department of Soil and Environmental Sciences.
Agronomy Journal, Vol. 70, No. 3, p 381-387, May-June, 1978. 4 fig, 2 tab, 42 ref-
Descriptors: Desert plants, Soil-water-plant relationships, Salt tolerance.
Drought tolerance; Turgidity, Transpiration, Stomata, Xylem.
Jojoba (Simraondsia chinensis (Link) Schneider) is a desert shrub which can provide
a much needed substitute for sperm whale oil. Because of the absence of soil-
plant-water data for jojoba and the limited amount of such information for desert
plants in general, selected plants were water-and-salt-stressed in greenhouse soil
and sand culture experiments. Responses of leaf water, osmotic, and turgor poten-
tials to stress and associated stomatal behavior were studied.
78:021-016
FORAGE YIELD AND FERTILIZER RECOVERY BY THREE IRRIGATED PERENNIAL GRASSES AS
AFFECTED BY N FERTILIZATION,
Hanson, C.L., Power, J.F., and Erickson, C.J.
Northwest Watershed Research Center, Boise, Idaho, United States Department of
Agriculture.
Agronomy Journal, Vol. 70, No. 3, p 373-375, May-June, 1978. 3 tab, 5 ref.
Descriptors: Forage grasses. Hay, Nitrogen, Fertilization, Crop response,
South Dakota.
The purpose of this study, conducted in western South Dakota on heavy clay soils
was to determine forage yield responses and N recovery of three irrigated grasses-'
reed canarygrass, garrison creeping foxtail, and smooth brome—to single and split
N applications. Single N treatments consisted Of 0, 56, 112, 224, or 448 kg N/ha
applied in March. For the split N applications, these same rates were applied
both in March and again after the first hay fritting. Forage yields were maximum
64
-------
when the grasses were fertilized with 224 kg N/ha in the split applications. First
cutting forage N percentage varied between 0.8 to 2.8 for N rates of 56 kg N/ha
and above. The percentage of N was highest, frequently over 3%, in second cutting
forage from treatments receiving split fertilizer applications. Percent total
N recovered increased as fertilizer rate increased when all N was applied in March,
but recovery was highest for the split application of 224 kg N/ha.
78:021-017
EFFECT OF SLOW RELEASE FERTILIZER ON FERTILIZER RESIDUES AND ON YIELD AND
COMPOSITION OF FLUE-CURED TOBACCO,
San Valentin, G.O., Robertson, W.K., Johnson, J.T., and Weeks, W.W.
Philippines University, Banos College, Laguna 3720, Philippines, Department of
Agriculture.
Agronomy Journal, Vol. 70, No. 2, p 345-348, March-April, 1978. 9 tab, 7 ref.
Descriptors: Tobacco, Potassium, Fertilizers, Solubility, Nutrient removal,
Sulfur.
Tobacco was grown for 5 years on Lakeland fine sandy soil, a soil which retains
very little K. Split applications of K2SO4 were compared to single applications
of K2SO4 and resin- polyvinyl-, and S-coated K materials. Yields and chemical
composition of tobacco leaves and soil were used to measure the relative effective-
ness of K treatments. Yields and K contents of tobacco leaves were increased by
K fertilization. Split applications of K2S04 were more effective than single
applications at planting. In years with heavy rainfall, applying slowly-soluble
sources all at planting was better than applying K2SO4 in split application.
Potassium from slowly soluble materials was less readily leached than from K2SO4,
resulting in higher concentration of K within 60 cm of the surface at the time of
tobacco flowering. When various thickness of S were applied to give a range of
K release, the thicker coatings gave higher yields. Treatments that provided
higher K contents increased total alkaloids and decreased reducing sugars in the
first of the two years that they were measured. Application of K fertilizers
with reduced solubility should assure good yields, quality, and a high level of
K in tobacco.
78:021-018
DRY MATTER PRODUCTION AND TRANSLOCATION IN MAIZE SUBJECTED TO DROUGHT DURING
GRAIN FILL,
Jurgens, S.K., Johnson, R.R., and Boyer, J.S.
Illinois University, Urbana, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 4, p 678-682, July-August, 1978. 5 fig, 5 tab,
17 ref.
Descriptors: Corn (field), Moisture stress, Moisture deficit, Photosynthesis,
Translocation, Crop response, Crop production.
The objective of this research was to study the problem of yield loss to be
expected and the physiological mechanism that cause the loss due to dry condi-
tions most frequently occurring during the second half of the growing season of
maize (Zea mays L.). Drought was imposed during-the grain filling stage of
maize to determine Its relative effects on photosynthesis and translocation.
78:021-019
EFFECTS OF SOIL WATER STRESS ON GROWTH AND NUTRIENT ACCUMULATION IN CORN,
Verasan, V., and Phillips, R.E.
Kasetsart University, Bangkok, Thailand, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 4, p 613-618, July-August, 1978. 6 fig, 10 ref.
Descriptors: Moisture stress, Moisture deficit, Corn (field), Plant growth,
Nutrients, Plant physiology, Transpiration, Moisture tension.
The objective of this study was to more clearly delineate the effect of soil
water stress on growth and accumulation of nutrient ions in corn. Corn was
grown in the greenhouse in 20-liter pots containing soil from the Ap horizon
of Maury silt loam (Typic Paleudalfs) under two soil moisture treatments,
stressed and nonstressed. The relationship soil water potential and cumulative
evapotranspiration with nutrient accumulation and dry matter production were
more significant than the relationship of soil water potential with dry matter
65
-------
production and nutrient accumulation. Since water stress affects turgidity,
photosynthesis, respiration, cell enlargement, and other physiological processes
of the plant, it was concluded that cumulative transpiration is a better integrator
of the effects of these processes on plant growth than is soil water potential.
78:021-020
FIELD MEASURED AND SIMULATED CORN LEAF WATER POTENTIAL,
Reicosky, D.C., and Lambert, J.R.
Agricultural Research Service, Morris, Minnesota, United States Department of
Agriculture.
Soil Science Society of America Journal, Vol. 42, No. 2, p 221-228, March-April,
1978. 6 fig, 2 tab, 27 ref.
Descriptors: Sweet corn, Simulation analysis. Moisture content, Moisture tension,
Microenvironment, Stemflow.
The dynamic nature and magnitude of field-measured leaf water potential for sweet
corn (Zea mays L.) was compared with that predicted by the model TROIKA. Some
plant parameters for corn were estimated from the literature and field observa-
tion, whereas the moisture desorption curve and the hydraulic conductivity-water
content relationship were determined for the Varina sandy loam. Leaf water po-
tential-relative water content relationships were determined in the greenhouse.
Hourly microclimate data were used as input to the model, and the predicted and
observed value of leaf water potential were compared for 3 days during the growing
season. Generally, the model predicted leaf water potential with reasonable
accuracy throughout the day. Water potential gradients in the soil were small as
compared with those across the root and across the stomatal opening.
78:021-021
POTASSIUM UPTAKE BY ONION ROOTS CHARACTERIZED BY POTASSIUM/RUBIDIUM RATIO,
Baligar, V.C., and Barber, S.A.
Purdue University, Lafayette, Indiana, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 4, p 618-622, July-August,
1978. 8 tab, 15 ref, 3 equ.
Descriptors: Cations, Cation exchange, Potassium, Onions, Sweet corn, Selectivity,
Diffusivity, Root systems.
A common belief is that plant roots absorb cations from the solution phase of the
soil. Experiments with corn (Zea mays L.) using K/Rb ratio to evaluate the source
of K and Rb absorbed indicated the plant roots absorbed these ions in the ratio
of exchangeable K and Rb. The objective of this research was to study the source
of K and Rb absorbed from soil by onion (Allium cepa) roots since they do not have
root hairs and this may influence the uptake mechanism. Onions absorbed K/Rb with
a ratio which was intermediate between the ratio of exchangeable K and Rb and the
ratio of these cations in solution. In comparison with corn, onions absorbed K
at one-third the rate, but absorbed water three times faster so that mass flow
contributed a greater proportion of K absorbed by onions than that by corn. This,
rather than differences in root hairs may be the reason for the observed differences
in K uptake between corn and onions.
78:021-022
UPTAKE OF CADMIUM FROM PHOSPHATE FERTILIZERS BY PEAS, RADISHES, AND LETTUCE,
Reuss, J.O., Dooley, H.L., and Griffis, W.
Corvallis Environmental Research Laboratory, Corvallis, Oregon 97330.
Journal of Environmental Quality, Vol. 7, No. 1, p 128-133, January-March, 1978.
2 fig, 7 tab, 6 ref.
Descriptors: Heavy metals, Phosphates, Fertilizers, Cadmium.
Cadmium uptake from phosphate fertilizers by radish, lettuce, and garden peas was
investigated in the greenhouse. Reagent grade mono-calcium phosphate and concen-
trated superphosphate (CSP) were used as a P source on a coarse-textured acid soil.
The effect of mono-calcium phosphate compared with that of CSP on radish, lettuce
and peas was nonsignificant. On a medium-textured calcareous soil the use of this
CSP increased the Cd content of radish tops by about 80% and that of lettuce by 50%.
66
-------
The effect on radish roots from calcareous soil was nonsignificant. Pea seeds
and foliage on this soil were below our Cd detection limit. Uptake on both
soils was a linear function of the Cd content of the fertilizer. In the acid
soils, spot placement of fertilizer in comparison to mixing it with the soil re-
sulted essentially the same Cd uptake from CSP fertilizer. Spot placement of
Di-ammonium phosphate (DAP) almost completely eliminated Cd uptake from the
fertilizer. In the calcareous soil spot placement increased Cd uptake from the
CSP fertilizer, but slightly depressed uptake from DAP.
78:021-023
USE OF K/Rb RATIO TO CHARACTERIZE POTASSIUM UPTAKE BY PLANT ROOTS GROWING IN
SOIL,
Baligar, V.C., and Barber, S.A.
Purdue University, West Lafayette, Indiana, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 4, p 575-579, July-Auaust
1978. 3 fig, 5 tab, 18 ref, 2 equ.
Descriptors: Potassium, Root systems, Root development, Moisture uptake, Ion
exchange, Sweet corn, Growth chambers.
Interaction between the plant root and the soil on cation influx into the root
is not well understood. Use of the ratio of K/Rb, two ions absorbed inter-
changeably by the root, enables measurement of the K ion medium influencing K
influx into the root. In experiments with corn (Zea mays L.) grown in eight
soil-R systems in a growth chamber, the K/Rb ratio of uptake was similar to the
K/Rb ratio of the ions on the exchange sites, and not the K/Rb ratio of the
solution cations. The data may be interpreted to indicate that K and Rb on the
exchange sites had more influence on K and Rb flux into the root than K and Rb in
solution. Diffusion of K and Rb from the soil to H-saturated exchange membranes
was in the ratio of K/Rb in solution.
78:021-024
GROWTH AND ELEMENTAL COMPOSITION OF CORN AND BEAN SEEDLINGS AS INFLUENCED BY SOIL
APPLICATION OF COAL ASH, '
Adriano, D.C., Woodford, T.A., and Ciravolo, T.G.
savannah River Ecology Laboratory, P.O. Drawer E, Aiken, South Carolina 29801.
Journal of Environmental Quality, Vol. 7, No. 3, p 416-421, July-September, 1978.
5 tab, 43 ref.
Descriptors: Coal mine wastes, Corn (field), Beans, Crop production, Soil chemical
Properties, Fossil fuels, Fly ash, Toxicity, Salinity, Deficient elements.
Analyses of O.lN HC1 extracts of ash (slag + fly ash) samples from bituminous coal
•revealed high concentrations of K, Ca, and Fe and intermediate concentrations of P,
M9/ Cu, Mn, and Zn. Of the elements analyzed, the extractable concentrations in-
creased as particle size decreased from >1,000 micron to <105 micron. The slightly
acidic ashes were mixed with Troup sandy loam at rates of 5, 10, and 20% by weight
and equilibrated in a glasshouse for 1 mo before planting. "Coarse" ash was used
at only the 10% rate. Corn and bush bean yields from ash-amended soils were
statistically equal to yields from a control treatment but significantly lower than
fertilized treatment. Corn exhibited P deficiency symptoms while symptoms charac-
teristic of B toxicity occurred in beans. Analyses of tissues of both crops indi-
cated that P concentrations were at deficiency levels while Cu, Mn, and Zn were
deficient to marginal. Iron, however, appeared to be in the normal range.
Salinity as indicated by EC of leachate of 3 mmhos/cm or greater, B excess as
indicated by the toxicity symptoms in beans, and P deficiency as indicated by
low p concentrations in plant tissues could limit crop growth in ash-treated soils.
78:021-025
CORN PRODUCTION AS INFLUENCED BY IRRIGATION AND SALINITY—UTAH STUDIES,
Hanks, R.J., Ashcroft, G.L., Rasmussen, V.P., and Wilson, G.D.
°tah State University, Logan, Department of Soil Science and Biometeorology.
Irrigation Science, Vol. 1, No. 1, August, 1978, p 47-59. 9 fig, 3 tab, 8 ref.
Descriptors: Irrigation, Salinity, Corn (field), Moisture stress, Moisture deficit,
Growth stages, Saline water, Evapotranspiration, Crop production, Crop response.
67
-------
This paper reported the results of a two-year field study at Logan, Utah which
was one of a series of similar experiments carried out at Fort Collins, Colorado,
Davis, California and Yuma, Arizona. A range of water application rates were
imposed using a line-source system and in some treatments water was withheld
during certain growth stages. Salinity variables were imposed by presaliniza-
tion before planting and by the use of saline irrigation water. Regardless of
irrigation or salinity regime, corn grain and total dry matter production were
linearly related to evapotranspiration, which was measured as the sum of irriga-
tion, rainfall and soil water depletion minus drainage. Presalinization of the
soil decreased yields in proportion to the salinity imposed, the decrease being
associated with reductions in evapotranspiration caused by reduced soil water
depletion as compared to the nonsalinized treatments.
78:021-026
THE EFFECT OF SUPPLEMENTAL IRRIGATION AND NITROGEN FERTILIZATION ON WHEAT
(TRITICUM AESTIVUM L.),
Shimshi, D., and Kafkafi, U.
Regional Experiment Station, Agricultural Research Organization, Mobile Post
Negev 2, Gilat, Israel.
Irrigation Science, Vol. 1, No. 1, August, 1978, p 27-38. 2 fig, 7 tab, 13 ref.
Descriptors: Supplemental irrigation, Fertilization, Nitrogen, Wheat, Crop
response, Crop production. Growth stages.
During 1971/72 an experiment was conducted at the Gilat Regional Experiment
Station in the Negev region of Israel, in which the combined effect of irrigation
and nitrogen fertilizer on wheat was studied. The following aspects were investi-
gated: the general nature of the interaction of irrigation and nitrogen on crop
yields and the effect of nitrogen on water use and water relations of the wheat
plant.
78:021-027
EFFECTS OF CHELATED IRON ON THE GROWTH OF TWO SPECIES OF VALLISNERIA,
Dooris, P.M., and Martin, D.F.
South Florida University, Tampa, Department of Biology and Chemistry.
Water Resources Bulletin, Vol. 14, No. 5, p 1088-1093, October, 1978. 4 tab,
12 ref.
Descriptors: Aquatic plants, Iron, Nutrient requirements, Plant growth, Florida,
Water management (applied).
Iron, added as (Fe-EDTA)(-), was found stimulatory to V. spiralis at a concen-
tration of 0.05 ppm. (Fe-EDTA)(-) had no effect upon growth of V. neotropicalis
as measured by changes in dissolved oxygen and dry weight. Results were compared
with those derived from similar studies with Hydrilla verticillata and Egeris
densa. The implications of lake drawdown and aeration were discussed.
78:021-028
ABSORPTION RATES OF AMMONIUM AND NITRATE BY RED KIDNEY BEANS UNDER SALT AND WATER
STRESS,
Frota, J.N.E., and Tucker, T.C.
Arizona University, Tucson, Department of Soil, Water and Engineering.
Soil Science Society of America Journal, Vol. 42, No. 5, p 753-756, September-
October, 1978. 2 fig, 5 tab, 21 ref.
Descriptors: Salinity, Moisture stress. Absorption, Ammonium salts, Nitrates,
Beans, Moisture deficit. Crop production. Crop response, Nitrogen.
The purpose of this study was to gain additional knowledge regarding the influence
of salinity and water deficit on plant uptake of NH4(+) and NO3(-). The absorption
patterns of NH4(+) and N03(-) by red kidney beans (Phaseolus vulgaris L.) were
determined under normal conditions (water stress) using an inverse isotope dilution
technique with 15N. Salt and water stress inhibited the absorption of both NH4(+)
and NO3(-). There was no difference between these two stress treatments in NH4(+)
uptake, but carbowax restricted N03(-> uptake more than did NaCl. Under NaCl
salinity the plants absorbed the same amount of N independent of N source; under
68
-------
water stress more NH4(+) than N03(-) was absorbed. Water absorption was reduced
y both stress treatments; N and water uptake were highly correlated. Root
permeability decreased in plants subjected to stress. Dry matter production
ana total N per plant decreased, but the N percentage increased in the stressed
78:021-029
SALT AND WATER STRESS INFLUENCES NITROGEN METABOLISM IN RED KIDNEY BEANS,
trota, J.N.E., and Tucker, T.C.
Arizona University, Tucson, Department of Soils, Water and Engineering.
soil science Society of America Journal, Vol. 42, No. 5, p 743-746, September-
October, 1978. 6 tab, 27 ref.
Descriptors: Salinity, Moisture deficit, Nitrogen, Metabolism, Beans, Crop
production.
oth salinity and water deficit reduce yields of crop plants. This study was an
3"emPfc to provide a better understanding of these stress effects on N metabolism
vul • utilization of NH4-N and NO3-N. Red kidney bean plants (Phaseolus
in aris L'' were grown under salt stress (NaCl) , water stress (carbowax) , and
ac-a normal nutrient solution (control). The 15N in N03(-), NH4(+), alpha amino
m f' total soluble-N and protein-N in plant shoots were analyzed after the
48 h received 15(NH4)2S04 and K15NO3 in nutrient solution for 6, 12, 24, and
N* 7°urs- Sodium chloride and carbowax . resulted in equal accumulations of N03-N,
. _ .' f and free alpha amino acids in bean shoots. Protein synthesis was
sal? i °antly reduced in bean shoots when the plants were subjected to NaCl
uni tv and carbowax, with either source of N, and the inhibition was more severe
unaer salt stress than water stress.
78:021-030
AMnX«G AND RATE OF FERTILIZER NITROGEN FOR SUGARBEETS RELATED TO NITROGEN UPTAKE
AND POLLUTION POTENTIAL,
Caltl' P:J-' Broadbent, F.E. , and Fried, M.
Jo nia University, Davis, Department of Soil Microbiology.
ournal of Environmental Quality, Vol. 7, No. 3, p 368-372, July-September, 1978.
* f 3 tab, 11 ref.
bee£riptors : Nitrogen, Fertilization, Timing, Nutrient requirements, Sugar
ee«, Water pollution, Crop production, Tracers.
as"trC?en ^N' uptake by sugarbeets (Beta vulgaris L.) from fertilizer and soil,
in ^ lated to time and rate of application, was evaluated at Davis, California,
si.° field experiments utilizing 15N-deleted ammonium sulfate. There were no
was Cant differences in root, top, or sugar yield when fertilizer N (135 kg/ha)
or appliecj at planting, at thinning, split equally between thinning and layby,
suh ? e<3ually between planting, thinning, and layby. Also, there were no
to ^tantial differences in soil or fertilizer N in tops and roots in response
Wer se dates of application. Fertilizer N recovery was 47% when 112 kg N/ha
a_ e.aPPlied to achieve maximum sugar yield. Roots removed as much N as that
tim 3nd tops contained an additional 105 kg N/ha. When applied N was 2.5
as the amount required for maximum sugar yield, tops and roots contained almost
a much N as applied. The sugarbeet crop, carefully fertilized, has potential for
ij-eviation of nitrate pollution of groundwater.
RELATIONS OF CADMIUM-TREATED PLANTS,
m, M.B.
Jo,,homa Sfcate University, Stillwater, Department of Agronomy.
•> finai °f Environmental Quality, Vol. 7, No. 3, p 334-336, July-September, 1978.
* 1 tab, 21 ref.
s®?criptors: Turgidity, Water pressure, Osmotic pressure, Cadmium, Transpiration,
QiJ.-water-plant relationships.
69
-------
Turgor pressures, stomatal resistances, and transpiration rates were measured
during a 50-day period in leaves of chrysanthemum (Chrysanthemum morifolium
Ramat. "Indianapolis White") plants grown in nutrient solution with 0, 0.01,
0.1, and 1.0 microgram/ml Cd added as CdS04. At harvest, dry weight and Cd
concentrations in roots, steins, and leaves were determined. Leaf abscission
occurred on Cd-treated plants. Turgor pressures were highest in plants grown
with 0.01 microgram/ml Cd and lower in plants treated with 0, 0.1, and 1.0 micro-
gram/ml Cd. Stomatal resistances were lowest in plants grown with 0.01 microgram/
ml Cd and progressively higher in plants treated with 0, 0.1, and 1.0 microgram/
ml Cd. Results indicated that quantities of Cd permitted in irrigation water in
the United States (0.05 microgram/ml) might be detrimental to growth because of
reduced turgor pressure and increased stomatal resistance.
78:021-032
EXTRACTABILITY OF CADMIUM, COPPER, NICKEL, AND ZINC BY DOUBLE ACID VERSUS DTPA
AND PLANT CONTENT AT EXCESSIVE SOIL LEVELS,
Korcak, R.F., and Fanning, D.S.
United States Department of Agriculture, Science and Education Administration,
Fruit Laboratory, Beltsville Agricultural Research Center-West, Beltsville,
Maryland.
Journal of Environmental Quality, Vol. 7, No. 4, p 506-512, October-December, 1978.
1 fig, 9 tab, 18 ref.
Descriptors: Trace elements, Elements (chemical), Heavy metals, Corn (field),
Sewage sludge, Correlation analysis, Cadmium, Copper, Nickel, Zinc.
Cadmium, copper, nickel, and zinc were applied as sulfate salts to samples of
surface horizons of three Maryland soils in the greenhouse at rates of metals
equivalent to those in 0 to 896 dry metric tons/ha of Washington, D.C., digested
sewage sludge. The sludge was also applied at a rate of 224 dry metric tons/ha.
Two pH regimes, approximately 5.5 and 6.5, were maintained. Metals were extracted
by the DTPA (diethylenetriaminepentaacetic acid buffered at pH 7.3) or double acid
(0.05N HC1, 0.025N H2S04) extractants. Correlations were determined between
extractable soil metals and metal content of two crops of corn (Zea mays L.)
each grown for 30 days, but at times of 1 or 13 mo after making the chemical
amendments to the soils. The results of the experiments were reported.
78:021-033
THE UPTAKE OF 203Hg-LABELED MERCURY COMPOUNDS BY BROMEGRASS FROM IRRIGATED
UNDISTURBED SOIL COLUMNS,
Hogg, T.J., Bettany, J.R., and Stewart, J.W.B.
Saskatchewan University, Saskatoon, Saskatchewan, Canada, Institute of Pedology.
Journal of Environmental Quality, Vol. 7, No. 3, p 445-450, July-September, 1978.
1 fig, 8 tab, 17 ref.
Descriptors: Mercury, Sewage effluent. Sewage disposal, Environmental effects,
Bromegrass, Irrigation, Volatility, Leachate, Organic matter.
Bromegrass (Bromus inermis) was grown under conditions of sewage effluent irrigation
on undisturbed soil columns in which the 0- to 10-cm layers had been treated with
10 micrograms Hg/g soil as 203Hg-labeled mercuric chloride (HgC12), phenyl
mercuric acetate (PMA), and methyl mercuric chloride (MMC). Mercury concentra-
tions in. plant dry matter decreased over three successive harvests and highest
values were found on MMC-treated soils of fine texture and low organic matter
content (2.0 to 0.2 micrograms Hg/g for first and third harvest, respectively).
Exposure of the plants and soils to simulated fall conditions resulted in a small
but significant increase in the Hg concentration of plant dry matter. Higher levels
of Hg were found in plant stems than plant foliage at the termination of the experi-
ment and even higher levels in the main roots and fine roots separated from the 0-10
cm soil layer. Mercury concentration of root decreased with depth for all Hg treat-
ments, but were still 150 times greater than background levels in the MMC-treated
soils at the 40- to 60-cm depth. A significant amount of all forms of applied
Hg (10-32%) was lost during the experiment, presumably by volatilization. The
majority of the remaining Hg in the soil was found to be strongly bound and not
extractable by weak salt solutions, dilute acids, and chelates.
70
-------
78:021-034
CORN YIELD RESPONSES TO WATER STRESS MANAGEMENT,
Stegman, E.G., and Aflatouni, M.
North Dakota State University, Fargo, Department of Agricultural Engineering.
Paper No. 78-2558, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978', Palmer House Hotel, Chicago,
Illinois, 9 p. 8 fig, 3 tab, 18 ref, 1 equ.
Descriptors: Moisture stress, Evapotranspiration, Crop response, Corn (field),
Moisture deficit, Growth stages, Irrigation, Water management (applied), Water
requirements, Irrigation systems.
Relative yield (Y/Ymax) vs. relative evapotranspiration (ET/ETmax) functions were
defined for major growth periods. These functions also suggested some yield loss
may occur due to water stress before an ET depression necessarily also occurs.
Relative yield attainment was also related to minimum levels of leaf xylem pressure
just prior to stress relief in given growth stages.
78:021-035
PREDICTING YIELDS,
Haun, J.R.
Clemson University, South Carolina, Department of Horticulture.
Crops and Soils Magazine, Vol. 31, No. 2, p 7-9, November, 1978. 3 fig.
Descriptors: Crop production, Crop response, Climatic data, Weather data, Plant
growth.
This paper presents a new concept in the evaluation of plant-environment relations
for developing yield prediction systems. This approach involves the daily mea-
surement of plant response in the field under natural, uncontrolled variations
in weather conditions. These plant growth data, with associated weather variables,
are to be analyzed by computer to develop the yield prediction system.
78:021-036
SOYBEAN CROP WATER REQUIREMENTS,
Dominguez, J., Horta, M. , and Robledo, E.
Regional Center of Agricultural Research No. 06, CRIDA 06, Spain, Department of
Cereals and Legumes .
ICID Bulletin, Vol. 27, No. 2, p 30-35, July, 1978. 3 fig, 22 ref.
Descriptors: Soil-water-plant relationships, Water requirements, Soybeans,
Moisture deficit, Moisture stress, Growth stages, Water management (applied),
Evapotranspiration, Yield equations, Crop production.
In experiments carried out in the three-year period 1974-1976, in "Pinca El Encin",
CRIDA 06, Alcala de Henares, on soybean crops irrigated by sprinklers, Amsoy
variety, a very high correlation between the RET (Real Evapotranspiration) in the
flowering and pod formation period and the final grain production was found. This
suggested, on the one hand, subjecting the plant to an initial deficit to adequately
develop the root system and on the other, ': supply ing quantities of about 9 mm during
the said period, which should increase the production level to 4,000 kg/hectare.
Penman's modified formula for daily application, following the guidelines of the
Irrigation Management Service, proved to be inadequate in the sense that it pro-
vided low ETP values. A greater consideration of the aerodynamic term was suggested
by the influence that the advective effect has on irrigation areas. with arid cli-
mates. For practical experiments the scheme proposed in the DWR-UCD Meeting 1975
based, on the utilization of the distribution curves of a water sprinkler, was
proved satisfactory, leading to a more reliable analysis, and to a simplification
of the experimental procedure.
78:021-037
WATER BALANCE OF FLOODED RICE PADDIES,
Brown, K.W., Turner,. F.T., Thomas, J,C,, Deuel, L,E,, a.nd Keener. M.E.
iexas ASM University, College Station, Department o? Soil and Crop Sciences,
" ""^ Manaement Vo1' 1 No- 3 2-
,
3 tab" ""^ Management' Vo1' 1' No- 3' P 277-291, November, 1978. 10 fig,
71
-------
Descriptors: Water balance, Submerged plants, Flood irrigation. Rice, Water
management (applied), Water requirements, Evapotranspiration, Runoff.
2
Rice (Oryza sativa L., var. Labelle) was grown in 300 m paddies of Beaumont clay
soil (Typic pelludert) and subjected to two management schemes of flooded rice
culture. These schemes were continuous irrigation and intermittent irrigation.
Careful measurements of irrigation, precipitation, evapotranspiration, deep
percolation and runoff were made, and the total water balance for the two water
management schemes was calculated. The results showed continuous irrigation to
be very wasteful of water with slightly over 1 m of irrigation water applied to
supply an evapotranspirational need of 0.5—0.6 m. The intermittent irrigation
management was less wasteful but still could be improved upon. Suggestions were
presented for techniques to help improve the water use efficiency and reduce
runoff losses.
78:021-038
SEASONAL WATER USE BY WINTER WHEAT GROWN UNDER SHALLOW WATER TABLE CONDITIONS,
Saini, B.C., and Ghildyal, B.P.
G.B. Pant University of Agriculture and Technology, Pantnagar, Distr. Nainital,
India.
Agricultural Water Management, Vol. 1, No. 3, p 263-276, November, 1978. 10 fig,
1 tab, 27 ref.
(See 78:02G-076)
78:021-039
LEAF OSMOTIC POTENTIAL AS AN INDICATOR OF CROP WATER DEFICIT AND IRRIGATION NEED
IN RAPESEED (BRASSICA NAPUS L.),
Clarke, J.M., and Simpson, G.M.
Research Station, Research Branch, Agriculture Canada, Swift Current, Saskatchewan
S9H 3X2, Canada.
Agricultural Water Management, Vol. 1, No. 4, p 351-356, December, 1978. 2 fig,
3 tab, 8 ref.
Descriptors: Moisture deficit, Moisture content, Water requirements, Moisture
stress, Moisture tension, Leaves, Scheduling, Tensiometers, Osmotic pressure,
Crop production.
Leaf osmotic potentials (LOP) of field-grown rapeseed (Brassica napus L.) were
measured in 1975 and 1976 under rainfed conditions and at two levels of irrigation.
Irrigations were scheduled on the basis of tensiometer measurements in 1975, and
on the basis of LOP in 1976. The LOP of rainfed plants was lower (more negative)
than that of irrigated plants. Leaf osmotic potential responded to changes in
soil moisture caused by precipitation or irrigation. Tensiometers placed at 0.2
m depth in the high irrigation treatment were as responsive to soil moisture
changes as LOP. Scheduling of irrigations on the basis of LOP in 1976 produced
yield differences between water regimes similar to those obtained in 1975. It
was concluded that leaf osmotic potential provides a satisfactory means for
determining need for irrigation in B. napus.
78:021-040
RESPONSE TO CORN TO LIMITED IRRIGATION ON SANDY SOILS,
Wilson, G.D., Watts, D.G., and Fischbach, P.E.
Nebraska University, North Platte, Department of Agricultural Engineering.
Paper No. 78-2554, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 11 p. 6 fig, 5 tab, 3 ref, 1 equ, 3 append.
Descriptors: Irrigation, Moisture deficit, Irrigation effects, Water management
(applied), Growth stages, Plant populations, Yield equations, Corn (field),
Water requirements, Crop production.
The objective of this experiment was to provide information for producers to enable
them to make sound decisions concerning irrigation management when water is limited.
Five irrigation management systems were evaluated on a Valentine very fine sand
(Typic Ustipsamment) in North Central Nebraska in 1977 and 1978. Two management
systems included limited irrigation. The latter were subdivided into three treat-
ments each in 1977 providing a total of six discrete limited irrigation treatments.
72
-------
Another treatment was added in 1978 making a total of seven limited irrigation
treatments. In each year, the limited irrigation treatments were compared to
nonirrigated and fully irrigated checks. Significant water savings were achieved
with the limited irrigation treatments. Yield variation from full irrigation
yields ranged from 4750 kg/ha reductions to 900 kg/ha increases. As much as
12.2 cm of irrigation water were saved with no yield reduction, even though water
use was reduced. Irrigation response ratio was defined as the yield increase
over the nonirrigated crop per unit of water applied. It was presented as a
management tool and was significantly affected by limited irrigation.
78:021-041
EVALUATION OF CROP WATER STRESS UNDER LIMITED IRRIGATION,
Heermann, D., and Duke, H.
Agricultural Research, Science and Education Administration, Fort Collins,
Colorado, United States Department of Agriculture.
Paper No. 78-2556, Presented at the 1978 Winter Meeting of the American Society
°f Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 5 p. 8 fig, 8 ref.
Descriptors; Moisture stress. Moisture deficit, Sprinkler irrigation, Soil
moisture, Yield equations, Corn (field), Growth stages, Water requirements.
Limited water application plots were established under 2 center pivot systems
Planted to corn. Stress was quantified by measuring water applied, soil water,
canopy temperatures and plant water potentials. Yield reductions were linearly
related to applied water and average canopy temperature differences between control
and stressed plots.
78:021-042
IRRIGATED CORN YIELD RESPONSE TO WATER,
Musick, J.T., and Dusek, D.A.
southwestern Great Plains Research Center, Bushland, Texas, United States Department
Paper No. 78-2557, Presented at the 1978 Winter Meeting of the American Society of
Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago, Illinois
**> p. 8 fig, 3 tab, 16 ref. '
Descriptors: Irrigation, Crop response, Moisture deficit, Evapotranspiration,
Moisture stress, Corn (field), Water requirements. Yield equations, Growth stages
water management (applied).
Corn grain yield response to water deficits and seasonal evapotranspiration-yield
relationships were determined during a 3-yr study in the Southern High Plains.
sensitivity of yields and water-use efficiencies to plant-water stress indicated
tnat limited irrigation should not be practiced in the high-evaporative demand
climate.
78:021-043
MAGNESIUM UPTAKE FROM EXCHANGEABLE AND NONEXCHANGEABLE SOURCES IN SOILS AS MEASURED
BY INTENSIVE CROPPING,
Christenson, D.R., and Doll, E.G.
Michigan State University, East Lansing, Department of Crop and Soil Sciences.
Soil Science, Vol. 126, No. 3, p 166-168, September, 1978. 4 tab, 6 ref.
Descriptors: Magnesium, Nutrients, Minerology, Greenhouses, Nutrient removal,
°ats, Michigan, Plant growth.
Several soils were cropped with four consecutive crops of oats (Avena sativa,
Garry") in the greenhouse. Changes in exchangeable Mg levels were used to indi-
cate uptake from that source. The remainder of the uptake was attributed to the
nonexchangeable source. Total uptake by the four crops did not appear to be
related to total Mg level in the soil, percent clay in the soil, or exchangeable
Mg level. Mg availability did appear to be related to the mineralogy of the
medium clay fraction.
73
-------
SECTION X
WATER CYCLE
EROSION AND SEDIMENTATION (GROUP 02J)
78:02J-001
A SIMPLE LABORATORY APPARATUS TO MEASURE RELATIVE ERODIBILITY OF SOILS,
Chandra, S., and De, S.K.
Allahabad University, India.
Soil Science, Vol. 125, No. 2, p 115-121, February, 1978. 3 fig, 3 tab,' 18 ref.
Descriptors: *Erosion rates, *Measurement, *Erosion, *Erodibility, Soils,
Laboratory equipment, Laboratory tests, Clays, Soil conservation. Instrumentation.
A simple laboratory apparatus designed for rapid and inexpensive measurement of
the relative erodibility of soils was described. Erosion coefficients obtained
with this apparatus were correlated with other erosion indices, viz., erosion
ratio, clay ratio, and silicarsesquioxide ratio, and were found to be in good
agreement. This apparatus can be used where routine analysis is required of a
large number of soil samples for their relative erodibility by water.
78:02J-002
EROSION RATES OF COHESIVE SOILS,
Ariathurai, R., and Arulanandan, K.
Nielsen Engineering and Research, Incorporated, Mountain View, California.
Journal of the Hydraulics Division, Proceedings of the American Society of Civil
Engineers, Vol. 104, No. HY2, Technical Notes, p 279-283, February, 1978. 5 fig,
4 ref, 1 append.
Descriptors: *Erosion rates, *Cohesive soils, *Laboratory tests. Erosion, Soils,
Shear stress, Clays, Soil types, Cation exchange, Loam, Illitie, Temperature,
Chemical properties, Mechanical properties, Expansive soils, Testing procedures,
Yolo loam. Sodium adsorption ratio.
The objective was to describe the effects of the principal physical and chemical
factors on the rate of erosion of saturated cohesive soils. A number of remolded
samples with different types and amounts of clay and different pore fluid composi-
tions were preconsolidated in a 7.6-cm diam cylindrical tube at a normal stress of
1 kg/sq cm. After consolidation, the samples were placed in the eroding fluid
to be used and were allowed to swell for a few hours. The results of erosion
tests on over 200 natural and made-up soil samples indicated that the erosion
rate constant M lies in the range 0.003 g/sq cm x min to 0.03 g/sq cm x'min with
few exceptions. The slopes of the erosion rate curves increases,.with increase
in critical shear stress. If the relationship between s and critical shear stress
were inverse, then M would be independent of the critical shear stress, although
N may vary with other*chemical and physical parameters. If further measurements
designed to investigate the relationship between the erodibility constants criti-
cal shear stress and M should yield a functional relationship between the two,
there will be one less parameter to deal with in problems such as the determina-
tion of soil yield from watersheds, and estuarial sediment transport.
78:02J-003
PHYSICAL, CHEMICAL, AND MINERALOGICAL PROPERTIES OF FLUVIAL UNCONSOLIDATED BOTTOM
SEDIMENTS IN NORTHWESTERN OHIO,
Wall, G.J., Wilding, L.P., and Smeck, N.E.
Guelph University, Ontario, Canada NIG 2W1, Agricultural Canada.
Journal of Environmental Quality, Vol. 7, No. 3, p 319-325, July-September, 1978.
5 fig, 5 tab, 16 ref.
Descriptors: Fluvial sediments, Unconsolidated sediments, Chemical properties,
Physical properties, Minerology, Water pollution, Water quality, Heavy metals,
Sediment load, Suspended load.
74
-------
Fluvial unconsolidated bottom sediments that have the potential to become part of
the suspended sediment load in the Maumee River Basin, Ohio, ranged in texture from
sandy loams to' clays. The water-dispersible clay was lower in mica but higher in
expandable 14 A (smectite) and quartz constituents than the electrolyte-dispersible
clay. The mineralogy of clay-sized bottom sediments from upstream agricultural
drainage ditches, major Basin tributaries, and from the Maumee River were found to
be essentially identical. The 2- to 50-microns fraction was dominated by quartz
with secondary amounts of mico, kaolinite, feldspars, and carbonates. Mean
calcite, dolomite, and calcium carbonate equivalent values were 4.1, 3.4, and 7.8%,
respectively. Organic matter content of the fluvial bottom sediments (3 to 7%)
was analogous to Lake Erie bottom sediments and Maumee River suspended sediments.
CEC values ranged from 39 to 55 meq/100 g for the total clay fraction. Enrichment
of heavy metals of bottom sediments over surficial soil materials occurred for Cu,
Ni, Zn, Ca, and Pb by factors of 1.6, 2.0, 2.3, 3.5, and 3.0, respectively. Traces
of herbicides and insecticides were detected in the filtered stream water samples
and bottom sediment materials. Downstream trends in selected physical, chemical,
and mineralogical properties could not be related to increased urban influences or
increased stream discharge.
78:02J-004
UNIT SEDIMENT GRAPH,
Rendon-Herrero, O.
Mississippi State University, Starkville, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 889-901, October, 1978. 12 fig, 3 tab,
23 ref, 3 equ.
Descriptors: Sediment discharge, Suspended load, Unit hydrographs, Graphical
analysis, Graphical methods, Small watersheds, Surface runoff, Soil erosion,
Precipitation (atmospheric).
The unit hydrograph method was extended to sediment graph analysis, thus yielding '
a unit sediment graph. The method is applicable to small uniform watersheds where
the main contribution to suspended sediment transported in the drainage channels as
the result of runoff derives from upslope erosion, that is, from wash load and not
from entrained bed load material. Bixler Run, a small wash load-producing water-
shed near Loysville, Pennsylvania, was used as a data source in deriving unit
sediment graphs. The hydrographs and concomitant sediment graphs used were
generally parallel in shape and coincided during peak flow.
78:02J-005
DEPOSITION OF NONUNIFORM SEDIMENT ON CONCAVE SLOPES,
Davis, S.S., Foster, G.R., and Huggins, L.F. _ ...
Purdue University, Lafayette, Indiana, Department of Agricultural Engineering.
Paper No. 78-2519, Presented at.the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 19 p. 8 fig, 4 tab, 20 ref, 3 equ.
Descriptors: Sediment transport, Simulation analysis, Overland flow, Aggregates,
Sands, Sediment yield, Homogeneity, Heterogeneity, Slopes, Watersheds (basins).
A laboratory study was conducted to investigate behavior of simulated natural
sediments transported and deposited by overland flow. Aggregate substitutes and
sand were studied both as separate homogeneous-sediments and as weight proportionally
combined heterogeneous sediment mixtures.
78:02J-006
DESIGN AND OPERATION OF GRADIENT TERRACE SYSTEMS,
Bondurant, D.T., and Laflen, J.M.
Soil Conservation Service, Des Moines, Iowa.
Paper No. 78-2520, Presented at the 1978 Winter Meeting of the American Society
°f Agricultural Engineers, December- 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 7 p. 4 fig, 5 tab, 19 ref.
Descriptors: Terracing, Erosion control, Pollution abatement, Design criteria,
Costs, Water quality, Graded, Soil conservation, Water conservation, Sediment
control.
75
-------
Two types of gradient terraces were planned on each of two Iowa fields. Comparison
shows that the type of terrace selected will have a major effect on cost of
terracing and on farmer acceptance, but little effect on off-field water quality.
78:02J-007
EXCAVATED SEDIMENT TRAPS—WHAT RALPH WALDO EMERSON WAS REALLY TALKING ABOUT,
Tryon, C.P., Parsons, B.L., and Miller, M.R.
Mark Twain National Forest, Rolla, Missouri.
Paper No. 78-2089, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 10 p. 9 ref.
Descriptors: Sediment control, Sediments, Sediment load, Soil erosion, Detention
reservoirs, Erosion, Cost comparisons, Comparative costs, Missouri.
A decade of experience on large earth moving jobs in the Missouri Ozarks has
shown that excavated sediment traps are incomparably superior to small detention
dams in terms of cost, industry acceptance, and sediment trap efficiency.
78:02J-008
REDUCING STREAM SEDIMENT LOADS BY IRRIGATION DIVERSIONS,
Johnson, C.W., and Smith, J.P.
Northwest Watershed Research Center, Boise, Idaho,
Paper No. 78-2088, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 14 p. 4 fig, 4 tab,
11 ref.
Descriptors: Sediment control, Sediment load, Sediment discharge, Soil erosion,
Sediments, Streamflow, Diversion, Diversion structures, Irrigation, Idaho.
A streamflow, irrigation diversion, and suspended sediment study on the Reynolds
Creek Experimental Watershed in southwest Idaho shows the effectiveness of an
irrigation system in reducing downstream sediment loads. About 560 tonnes of
sediment per year was deposited on 690 ha of pasture, hay, and grain cropland,
an average deposition of 0.08 mm per year. The sediment from natural streamflow
is usually beneficial to crop production in this mountain valley.
78:02J-009
THE DESIGN OF SEDIMENT BASINS,
Ward, A.D., Haan, C.T., and Barfield, B.J.
Kentucky University, Lexington, Department of Agricultural Engineering.
Paper No. 78-2086, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 32 p.. 4 fig, 4 tab,
17 ref, 15 egu.
Descriptors: Sediment control, Sediments, Detention reservoirs, Design, Mining,
Mine wastes, Hydrologic aspects, Regression analysis, Simulation analysis,
Computer programs.
Passage of Public Law 95-87 has placed several new restrictions on the design of
surface mine sediment basins. It created much controversy as to the required
sizing of the sediment basins, and adequate design methods are not available for
estimating basin performance and effluent sediment concentrations. This paper
presents guidelines as to how the hydrologic parameters affecting sediment basin
design may be quantified and contains predictive equations for estimating' basin
trap efficiency and peak effluent sediment concentrations. Multiple regression
analysis techniques were employed with data generated by a hydrograph computer
program and by a simulation model. The simulation model has been tested on several
actual basins and appears to give a good estimate of basin performance. It also
gave a good estimate of the performance of Callahan Reservoir during a 60-day
period in 1973. A new version of the model allows for variation in the particle
size distribution with runoff rate, and in this paper criteria are presented which
account for basins with a permanent pool and also considers base flow conditions
following a design storm event.
76
-------
78:02J-010
SEDROUTE PROCEDURE FOR ESTIMATING EROSION AND SEDIMENT IMPACTS,
Kelly, G.D.
Manti-LaSal National Forest, Price, Utah.
Paper No. 78-2081, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 7 p. 4 ref, 3 equ.
Descriptors: Sediment yield, Surface runoff, Runoff, Sediments, Model studies,
Sediment load, Data processing, Mining, Sediment control, Idaho.
The SEDROUTE procedure predicts the amount and charge in erosion and sediment
yield that will occur from a proposed project. The model uses a minimum of data
and responds to changing project details. Impacts are routed downstream to show
the effects of other water and sediment sources.
78:02J-011
SEA RESEARCH PROGRAM FOR CHANNEL STABILITY AND GULLY CONTROL,
Little, W.C., Piest, R.F., and Robinson, A.R.
Paper No. 78-2080, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p. 13 ref.
Descriptors: Channel erosion. Channel improvement, Stability, Gullies, Gully
erosion, Stream erosion, Stabilization, Research and development. Environmental
effects.
There are a multitude of factors relating to problems of unstable channels and
active gullies. There are limited methods of control and additional cost
effective methods are required. The potential for improved technology is great.
The USDA, Science and Education Administration, Federal Research Program is
conducting research on stabilization of stream channels and control of gullies.
78:02J-012
EROSION SIMULATION FOR LAND USE MANAGEMENT,
DeCoursey, D.G.
Sedimentation Laboratory, Oxford, Mississippi, U.S. Department of Agriculture.
Paper No. 78-2Q82, Presented at the 1978 Summer Meeting of the'American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p. 6 fig, 8 tab.
Descriptors: Soil erosion, Erosion, Simulation analysis, Runoff, Surface runoff,
Sediment yield, Hydrographs, Land management, Land use, Cotton.
In May, 1976, a paper entitled "Philosophy of Erosion Simulation for Land Use
Management" by D.G. DeCoursey and L.D, Meyer was presented at a Soil Erosion
Workshop at Purdue University. The paper described schematically, a concept for
combining hydrology, infiltration, moisture redistribution, crop growth, and
rill-interrill erosion models to produce a dynamic simulation system that can be
assembled to evaluate the environmental impact of land management alternatives.
Most of the parameters are based on measurable factors or field tests. This
Paper describes such a simulation system and the data necessary to use it. Data
from a cotton field in the Mississippi Delta were used to test and refine the
system. Examples showing how the system can be used to evaluate alternative
land management schemes, are presented. Output from the system includes runoff,
sediment, and cotton production. They were used to show how factors such as
Plant population fertilizer, row spacing, land slope and tillage operations can
affect management alternatives.
78:02J-013
TOTAL LOAD OF BED MATERIALS IN OPEN CHANNELS,
Kikkawa, H., and Ishikawa, T.
Tokyo Institute of Technology, Japan, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY7, Proceedings Paper 13895, p 1045-1059, July, 1978. 10 fig, 12 ref, 2
append.
Descriptors: *Bed load, *Open channels, *Model studies, *Stochastic models,
Channel flow, Sediment transport, Stochastic processes, Suspended load, Hydraulics,
Sedimentation, Equations, Mathematical models, Bed material load, Sediment sources,
Synthetic models.
-------
Bed material load usually is classified into bed load and suspended load. They
have been treated individually in the previous theoretical studies, but to obtain
the expression of total load, their mutual relation must be formulated. The main
objective in this investigation was to study this relation. The basic consideration
was that the bed layer is formed under the balance of vertical forces acting on
sediment particles near and on the bed surface.and this layer can be regarded as
the source of sediments to be diffused to the region of suspended load. According
to this consideration: (1) a new stochastic model that interrelates bed load
and suspended load was considered to simulate the particle movement; and (2) the
equation of dynamic balance in the bed layer was introduced and improved by using
the results of basic experiments. A total load equation was derived by combining
the results of two processes. The data presented by U.S.G.S. were used to verify
it.
78:02J-014
DIFFUSION OF SEDIMENT IN LONG CHANNELS,
Aronsson, G.
Uppsala University, Sweden, Department of Mathematics.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY6, Proceedings Paper 13845, p 821-837, June, 1978. 7 fig, 12 ref, 1 append.
Descriptors: *Dispersion, *Diffusion, *Sediments, *Model studies, *Long channels,
Mathematical models, Distribution, Distribution patterns, Sediment distribution.
Spatial distribution, Channels, Turbulence, Sediment transport, Sedimentation,
Mathematics.
A model was presented, treating the transport of suspended material in a broad
channel under simplifying assumptions. The motion of sediment was treated as a
diffusion process, and a differential equation was derived. The form of an
"equilibrium distribution" g(y) was derived, corresponding to the classical distri-
bution of Prandtl and Rouse. Mathematically the following two results were
proven: (1) if a stationary (time dependent) state prevails downstream at a certain
point P, then the distribution downstream P tends (with increasing distance to
P) exponentially to the "equilibrium distribution"; and (2) if the sediment dis-
tribution in the incoming downstream P will tend to the stationary solution ex-
ponentially with time. Although these results seem to be physically evident, they
apparently have not been proven before.
78:02J-015
EROSION CONTROL/SEDIMENT MODELING—SOUTHERN IDAHO A PROGRESS REPORT,
Longley, T.S.
Idaho University, Aberdeen, Research and Extension Center.
Paper No. 78-2028, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 6 p. 3 fig, 4 ref,
12 egu.
Descriptors: Soil erosion, Erosion, Agricultural watersheds, Sediments, Sediment
load, Return flow, Idaho, Irrigation, Water quality, Model studies.
The progress of erosion control/sediment modeling was reported. The modeling
effort proceeded in three steps: (1) the furrow erosion submodel, (2) the instream
erosion control practice submodel, and (3) the routing method to route the water
down through the watershed. The furrow erosion submodel predicts the sediment
lost from an individual field using furrow hydraulic parameters and the stream power
concept explained below. The instream erosion control practice submodel predicts
the effectiveness of the best management practices in cleaning the sediment from
the return flow, and finally a routing procedure is used to move the flow and
associated sediment through the watershed.
78:02J-016
SCOUR OF BED MATERIAL IN VERY ROUGH CHANNELS,
Bayazit, M.
Technical University, Istanbul, Turkey, Department of Hydraulics and Water Power.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY9, p 1345-1349, September, 1978. 3 fig, 2 ref, 4 equ, 1 append.
78
-------
Descriptors: Scour, Open channel flow, Roughness (hydraulic), Beds, Velocity, Flow
characteristics, Vibrations.
In this paper an attempt was made to explain the relative roughness effect on the
scour of bed material in shallow depths on the basis of flow characteristics ob-
served in a previous study (Bayazit, J. of Hydraulic Res., 14(2), 1976). Experi-
ments with densely packed uniform spheres confirmed that the initiation of motion
of bed material is affected by the relative roughness of the channel. At shallow
depths, larger values of the Shields' parameter are required to initiate the motion.
This was explained by the reduction of nondimensional velocities at the bed level
with the increase of relative roughness. The effective value of the instantaneous
flow velocity was thus achieved at higher bed shear stresses in comparison with
flows at mild slopes.
78:02J-017
NUMERICAL STUDY OF CONTINUOUS SALTATION,
Reizes, J.A.
New South Wales University, Sydney, Australia, School of Mechanical and
Industrial Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY9, p 1305-1321, September, 1978. 12 fig, 15 ref, 31 egu, 3 append.
Descriptors: Saltation, Sediment transport, Numerical analysis, Mathematical
models, Computer programs, Bed load, Simulation analysis, Drag.
This paper reported a theoretical study of a particle in continuous saltation
involving a numerical solution of the three-dimensional equations of particle
motion including collision with the bed. Some of the difficulties and inaccuracies
associated with an experimental evaluation of bed load were avoided by the use of
a computer simulation of a saltating particle. Continuous saltation was possible
as the result of the proposed three-dimensional bed-particle interactions, even
in the absence of vertical fluid velocity component's and lift forces. Comparison
with experimental data suggested that the model is at least a reasonable represen-
tation of the process. It was shown that for an isolated particle near the bed,
an apparent lift force, which can be greater than the gravitational force, results
from the nonlinear drag force. It was also shown in this study that previously
attempted single parameter correlations are inadequate and that at least two
Parameters are required to collapse the numerical results into an orderly array
of curves. The Shields entrainment function and the particle Reynolds number were
modified to obtain two parameter correlations.
?8:02J-018
TRANSPORT OF A NONCOHESIVE SANDY- MIXTURE IN RAINFALL AND RUNOFF EXPERIMENTS,
Walker, P.H., Kinnell, P.I.A., and Green, P.
Sediment Transport Group, Division of Soils, Box 639, P.O. Canberra City, A.C.T.
2601, Australia.
Soil Science Society of America Journal, Vol. 42, No. 5, p 793-801, September-
October, 1978. 8 fig, 3 tab, 20 ref, 4 equ.
Descriptors: Raindrops, Runoff, Surface runoff, Suspension, Rainfall intensity,
Bed load, Suspended load, Overland flow, Soil erosion.
Rainfall intensities of 45, 100, and 150 mm/hr with systematically varied kinetic
energies were applied to a saturated noncohesive, sandy bed 3 m long and set at
slopes of 0.5 and 5%. Detailed size analyses of solids discharged showed that the
*31 micron fraction was most readily mobilized and behaved as a suspended load;
and 31- to 250-micron fraction was transported slowly, much apparently as saltating
bed load; the 0.25- to 4-mm fraction was transported rapidly, grains tending to
move as rolling bed load; the >4 mm fraction behaved as a lag gravel. The sedi-
mentary properties of bed deposits also reflected the differentiation of various
size fractions and minerals in the original mixture. The effects of raindrop im-
Pacts within the flow were more important in promoting transport of solids than
the aerial component of splash. Under conditions where overland flow had
developed, transport of solids was related directly to rainfall intensity and
variations in rainfall energy that were associated with variations in raindrop
impact frequency. Increases in rainfall energy due to increasing raindrop sizes
not result in increases in solids discharged.
79
-------
78:02J-019
SUBSURFACE DRAINAGE MODEL WITH ASSOCIATED SEDIMENT TRANSPORT,
Bottcher, A.B., Monke, E.J., and Huggins, L.F.
Florida University, Gainesville.
Paper No. 78-2502, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 21 p. 4 fig, 15 ref, 18 equ.
Descriptors: Subsurface drainage, Model studies, Computer models, Sediment
transport. Simulation analysis. Tile drainage, Water yield, Sediment yield,
Flow rates. Hydraulic conductivity.
A computer model was developed, using the GASP IV simulation language to simulate
the water flow and sediment movement from a subsurface drainage system. The model
uses a one dimensional form of the Richard's Equation and a steady state tile flow
formula by Toskoz and Kirkham to express the water movement process. The particle
detachment model, which is based on a force balance relationship, is driven directly
by the output of the flow model. Data required by the model includes rainfall,
evapotranspiration, soil properties, and the drainage system layout. Calibration
and verification was completed using data collected from a seventeen hectare tile
drainage system located on a flat Hoytville silty clay soil. A comparison of the
simulated and observed results indicate that the model will reliably predict
water yield, sediment yield and the sediment concentration curve. The model had
difficulty in simulating the actual shape of the flow hydrograph.
78:02J-020
FARM LEVEL ECONOMIC EVALUATION OF EROSION CONTROL,
McGrann, J.M.
Iowa State University, Ames.
Paper No. 78-2515, Presented at the 1978 Winter Meeting of the American Society of
Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago, Illinois,
13 p. 2 fig, 3 tab, 15 ref.
Descriptors: Erosion control, Soil erosion, Cost comparisons, Soil management,
Economic feasibility, Water pollution, Economic impact, Contour farming.
Farm level economic evaluation of erosion control alternatives in three major
soil associations in Iowa indicated that: (1) residue tillage and contouring is
the most cost effective alternative to reduce soil erosion, (2) the economic impact
of reducing soil loss is less on mixed crop and livestock farms than specialized
crop farms, and C3) although the economic impact of erosion control differs between
soil areas, reduction of soil loss below the 5 ton level can be accomplished through
conservation tillage in large areas of Iowa with little reduction in farm income
without public participation in farm level costs.
78:02J-021
EROSION INVENTORY-SHEET AND RILL EROSION,
Dideriksen, R.I., and Hidlebaugh, A.R.
Soil Conservation Service, Washington, District of Columbia.
Paper No. 78-2514, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 33 p. 3 fig, 14 tab, 13 ref.
Descriptors: Erosion, Soil erosion, Rill erosion. Sheet erosion, Wind erosion,
Erosion control, Data collections, Conservation.
Erosion by wind and water from farmland remains a serious problem in the United
States. This inventory takes a new look at the problem and provides current
information on natural and related resources on nonfederal land for all states
except Alaska. Nearly one quarter million randomly selected sample sites were
observed in the field and farm owners and operators were interviewed. The data
gathered in 1977 were used in the Universal Soil Loss and Wind Erosion models
to estimate the rate and amount of sheet, rill, and wind erosion for different
soils, land uses, and management systems.
80
-------
78:02J-022
EVALUATION OF GRASS CHARACTERISTICS RELATED TO SEDIMENT FILTRATION,
Hayes, j.c., Barfield, B.J., and Barnhisel, R.I.
Kentucky University, Lexington, Department of Agricultural Engineering.
Paper No. 78-2513, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago
Illinois, 21 p. 7 fig, 2 tab, 10 ref.
Descriptors: Sediment transport. Sediment control, Filtration, Grasses, Vegetation
effects, Sediment yield. Water pollution, Regression analysis, Rouahness coeffi-
cient, Watershed management. ' '
Vegetal filtration was proposed as a means of reducing sediment from disturbed
areas. Recent studies using simulated media have led to relationships which
define deposition within a grass filter. Several characteristic dimensions were
required to define the effects of vegetation on flow and sediment transport.
Quantification of these dimensions, sensitivity of the relations to errors in
measurement, and further verification data was included in the paper.
78:02J-023
NITROGEN AND PHOSPHORUS LOSSES IN RUNOFF FROM NO-TILL SOYBEANS,
McDowell, L.L., Ryan, M.E., McGregor, K.C., and Greer, J.D.
Sedimentation Laboratory, Oxford, Mississippi, United States Department of
Agriculture.
Paper No. 78-2508, Presented at the 1978 Winter Meeting of the American Society
°f Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 8 p. 10 fig, 4 tab, 18 ref.
(See 78:05G-043)
78:Q2J-024
A FINITE ELEMENT HYDROLOGIC MODEL TO DETERMINE THE EFFECT OF LAND MANAGEMENT
PRACTICES ON EROSION AND SEDIMENTATION IN A WATERSHED,
Ross, B.B., Shanholtz, V.O., and Contractor, D.N.
Virginia Polytechnic Institute and State University, Blacksburq, Department of
Civil Engineering.
Paper No. 78-2507, Presented at the 1978 Winter Meeting of the American Society of
Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 42 p. 11 fig, 7 tab, 41 ref, 12 equ.
Descriptors: Soil erosion, Sedimentation, Sediment transport, Erosion, Land
management, Flood routing, Finite element analysis, Water quality, Simulation
analysis, Model studies.
The use of a finite element flood routing model for simulating erosion and sediment
transport was proposed. A conceptual framework was provided whereby detailed
spatiotemporal variations in such factors as soils, landuse topography and rainfall
can be integrated to predict water quantity and quality to determine the effect
°f various landuse management practices on erosion and sediment transport.
78:02J-025
SEDIMENT SIZES ERODED FROM ROWCROP SIDESLOPES,
"eyer, L.D., Harmon, W.C., and McDowell, L.L.
Sedimentation Laboratory, Oxford, Mississippi, United States Department of
Agriculture.
PaPer No. 78-2518, Presented at the 1978 Winter Meeting of the American Society
°f Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 9 p. 7 fig, 4 tab, 13 ref.
Descriptors; Sediments, Sediment distribution, Simulated rainfall, Soil erosion,
Size, Rainfall intensity, Canopy.
Row sideslopes of ten soils were studied under simulated rainstorms to determine
the size distributions of their eroded (undispersed) sediment. The eroded sediment
sizes for different soils differed considerably. These distributions were com-
pared to the size distributions of the dispersed sediment and original surface
soil. The undispersed sediment was coarser than the dispersed soil or sediment,
much coarser for many soils. For each soil, the sediment size distribution changed
relatively little with major changes in rain intensity, continued erosion, and
crop canopy. 81
-------
78:02J-026
EROSION DEPOSITS IN TILE-DRAINS,
Paterson, E., and Mitchell, B.D.
The Macaulay Institute for Soil Research, Braigiebuckler, Aberdeen AB9 2QJ,
Great Britian.
Agricultural Water Management, Vol. 1, No. 4, p 311-317, December, 1978. 2 fig,
1 tab, 6 ref.
Descriptors: Tile drains, Tile drainage, Silting, Deposition (sediments). Soil
erosion, Sedimentation, Drainage.
The mechanism of silting up of tile field drains in two heavy textured surface
water gley soils was examined by comparing the physical and mineralogical
characteristics of deposits in drains with those of the clay soil directly above
The deposits consisted of clay, silt and sand and are distinctly laminated. They
appeared to be the result of internal erosion of the soil. The processes"operative
Mnnefnfc^ I6 *een! ^"i i?flow °f soil throu?h ^e drain joints; (b) sedimenta-
tion in the drain; (c) elution of very fine material. The possibility that this
silting-up phenomenon is not uncommon in the tile field drains of surface water
gley soils of Scotland was recognized.
78:02J-027
SIZE DISTRIBUTION OP ERODED MATERIAL FROM SIMULATED RAINFALL: EFFECT OVER A RANGE
OF TEXTURE,
Gabriels, D., and Moldenhauer, W.C.
State University, Ghent, Belgium, Department of Agricultural Sciences.
Soil Science Society of America Journal, Vol. 42, No. 6, p 954-958, November-
December, 1978. 1 fig, 4 tab, 16 ref.
Descriptors; Soil erosion, Erosion, Surface sealing, Particle size, Runoff,
Simulated rainfall, Soil texture, Soil aggregates, Water pollution.
This study reported size distributions and composition of material detached by water
drops and transported in shallow flow. The size distributions of aggregates and
primary particles in the splashed, washed, and seal material at different times
during a laboratory simulated rainfall were compared for different textured soils.
The wash had more finer material than did the splash. The wash and splash material
at equilibrium were not different from the original soil, while the seal of all
soils had a larger silt content than the original soils. The silt loam soil had
seals with about the same clay content as the original soil, while silty clay soils
had seals with less clay than the original soils. Of significance from this study
was the low percentage of dispersed clay being eroded compared to the percent of
Mm» lnT^en,«rigi?aV0il,,?« that this Percenta
-------
SECTION XI
WATER CYCLE
CHEMICAL PROCESSES (GROUP 02K)
78:02K-001
UTILIZATION OF LABELLED UREA AND AMMONIUM SULFATE BY LOWLAND RICE,
Reddy, K.R., Patrick, W.H., Jr.
Louisiana State University, Baton Rouge, Department of Agronomy.
Soil science Society of America Journal, Vol. 42, No. 3, p 465-467, May-June
1978. 4 tab, 4 ref.
Descriptors: Stable isotopes. Ureas, Ammonium compounds, Nitrogen, Fertilizers,
Fertilization, Rice, Flood irrigation.
The objective of this investigation was to compare labelled ammonium sulfate and
urea in their effect on yield and N utilization in field microplots on Crowley
silt loam (typic albaqualf). Nitrogen was applied as an early season topdressing
or as a midseason topdressing and the grain and straw yield and recovery of
labelled and native N in the grain straw, and soil were measured. No significant
differences in grain and straw yields were observed for the two sources and two
times of N application. Ammonium sulfate and urea did not differ significantly
in N utilization by the crop. For both sources the recovery of labelled N in
the soil-plant system was highest (34 to 55 kg N/ha) in the plots receiving early
season topdressing (30 to 38 kg N/ha). More native soil N was taken up by the
plants during 1976 as compared to the 1975 season.
78:02K-002
DETERMINATION OF STABILITY CONSTANTS OF METAL-HUMIC ACID COMPLEXES BY POTENTIO-
METRIC TITRATION AND ION-SELECTIVE ELECTRODES,
Takamatsu, T., and Yoshida, T.
National Institute for Environmental Studies, Yatabe-cho, Ibaraki, Japan, Water
and Soil Environment Division.
Soil Science, Vol. 125, No. 6, p 377-386, June, 1978. 8 fig, 4 tab, 19 ref, 14 equ.
Descriptors: Heavy metals, Humic acids, Electrodes, Pollutants, Copper, Cadmium,
Lead.
A new technique based on the combined use of potentiometric titration and ion-
selective electrodes was proposed for determining apparent stability constants
(successive stability constants and overall stability constants) of divalent metal
cation Cu(++), Pb(++), and Cd(++) complexes with humic acids. Fourteen humic
acids from diverse sources, including humidified rice straw, were examined. The
stability constants increased with an increase in pH, and the order of values
obtained was Cu{++) > Pb(++) »Cd(++). The overall logarithmic stability con-
stants with the soil humic acid examined were" 8.65 for Cu(++), 8.35 for Pb(++),
and 6.25 for Cd(++) at pH 5.0. The overall stability constants of Cd(++) complexes
ranged from 430,000 to 4.6 times 10 to the 7th power at pH 6.0. The overall
stability constants increased with increasing humification in the higher humifi-
cation range, and the values correspond to the contents of very weakly acidic
functional groups. The binding mechanisms of the metal cation complexes with
humic acids seemed to accompany the coordinate bonds of undissociated very weakly
acidic functional groups, in addition to the ionic bonds through COOH and/or OH
groups.
78:02K-003
FACTORS AFFECTING GYPSUM AND CATION EXCHANGE CAPACITY DETERMINATIONS IN GYPSIFEROUS
SOILS,
Sayegh, A.H., Khan, N.A., Khan,'P., and Ryan, J.
American University of Beirut, Lebanon, Department of Soils and Irrigation.
Soil Science, Vol. 125, No. 5, p 294-300, May, 1978. 4 fig, 15 ref.
83
-------
Descriptors: Cation exchange, Gypsum, Calcium, Magnesium, Sodium compounds,
Ammonium compounds. Soil profiles, Particle size.
Profiles of gypsiferous soils from the Euphrates basin of Iraq and Syria were
studied. Increasing fineness of grinding, from 10, 50, 100, and 170 to 270-mesh,
increased the measured amounts of gypsum and soluble Ca + Mg. These variables
also increased as the soilrwater ratio increased i.e., 1:50, 1:100, and 1:500.
Cation exchange capacity values at 10, 100, and 270-mesh sizes were determined by
various procedures: IN NaOAC/NH40AC solutions prepared with distilled water and
with 1:1 water-acetone mixture; pretreatments of the soil with 2N BaC12*2H2O,
saturated Na2C2O4, and saturated (COOH)2-2H20 by shaking for variable periods up
to six days. After each pretreatment, CEC was determined by the conventional
NaOAC/NH4OAC procedure. Highest values were obtained after pretreatment, the
order being Na2C204, BaC12-2H20, and (COOH)2-2H20. Values increased with time of
shaking during pretreatment and with increasing fineness of particle size.
Criteria are presented for determining gypsum and CEC in soils containing
significant amounts of gypsum.
78:02K-004
FERTILIZATION DECISION MODEL-A SYNTHESIS OP SOIL AND PLANT PARAMETERS IN A COM-
PUTERIZED PROGRAM,
Kafkafi, U., Bar-Yosef, B., and Hadas, A.
Institute of Soils and Water, Bet Dagan, Israel, ARO-The Volcani Center.
Soil Science, Vol. 125, No. 4, p 261-268, April, 1978. 1 fig, 2 tab, 43 ref,
3 append.
Descriptors: Fertilization, Computer models, Plant growth, Nitrates, Nitrogen,
Phosphates, Potassium, Ammonium compounds, Nutrient removal, Root development.
A fertilization decision model was suggested, based on soil and plant parameters.
The optimum concentration range of nitrate nitrogen in the soil solution, during
the uptake period of the growing plant, was suggested to be 50 to 250 ppm N-N03
for all soils and plants. The optimum bicarbonate-soluble P was found to vary
with plant and soil type, and was determined by response experiments. Percent
recovery of added fertilizer by bicarbonate extraction was used to calculate the
amount of fertilizer needed to raise the extraction'value to the optimum level.
Exchangeable potassium was considered to be the only source important during
the growing season of an annual crop. The uptake rate of nutrients during the
growing season, depth of root penetration, and sensitivity to ammonium were con-
sidered to be the main plant parameters. The model calculates, at preset time
intervals, the balance between the quantity of nutrients in the root zone and
uptake by plants. A decision to add fertilizer is made if a deviation from the
optimum exceeds a predetermined value.
78:02K-005
SIMULATION OF NITROGEN PROCESSES IN SOILS FOR ESTIMATING FERTILIZER REQUIREMENTS,
Kruh, G., Hagin, J., and Sharon, S.
Technion-Israel Institute of Technology, Haifa, Israel, Faculty of Agricultural
Engineering.
Soil Science, Vol. 125, No. 4, p 255-260, April, 1978. 3 fig, 2 tab, 19 ref.
Descriptors: Fertilization, Computer models, Simulation analysis, Cotton,
Ammonium compounds, Nitrates, Soil moisture, Crop response, Timing.
In a field experiment on cotton, ammonium sulfate was applied to give 60, 120, and
180 kg N/ha, all in winter, early spring, and late spring applications. A check
treatment was included. Soil samples to a depth of 120 cm were taken from time
to time, and moisture and nitrate concentrations were measured. The early spring
fertilization at the two lower levels of application produced higher yields than
the two other application times, with a maximum at the 120-kg N/ha level. The
highest level of application induced a yield depression. The early spring appli-
cation produced a nitrate distribution in the soil profile with a peak in the 20-
40 cm depth. The yield results were partially explained by the nitrate distri-
bution in the soil profile during the early growth period. A computer program
simulated well, within experimental errors, the nitrate distribution in the soil
profile. It was concluded that such a program could improve considerably nitrogen
fertilizer requirements and timing predictions.
84
-------
78:02K-006
HULA VALLEY PEAT: REVIEW OF CHEMICAL AND GEOCHEMICAL ASPECTS,
Brenner, S., Ikan, R., Agron., N.A., and Nissenbaum, A.
Hebrew University of Jerusalem, Israel, Department of Organic Chemistry.
Soil Science, Vol. 125, No. 4, p 226-232, April, 1978. 3 fig, 2 tab, 32 ref.
Descriptors: Peat, Chemical properties, Pleistocene epoch, Inorganic compounds,
Organic matter, Stable isotopes, Elements (chemical), Geochemistry.
In the Hula Valley, Israel, four layers of peat of Middle Pleistocene to Holocene
age, interbedded with limriic clays and marls, are found above 300-m depth. The
main detrital minerals are kaolinite, montmorillonite, and illite. Average ele-
mental values of organic and inorganic matters (on dry basis) present in each
horizon and average calorific values of each horizon are reported. Organic con-
stituents of the upper layer have been identified. A detailed.quantitative in-
vestigation of the distribution with depth in the top peat layer of the humic,
fulvic, and hymatomelanic acids, as well as of the beta-humus and humin, showed
humin to be the dominant fraction of the organic matter. Analysis of the peat
organic fractions for carbon and hydrogen stable isotopes shows that with depth
the difference in delta C13 between the humic and fulvic acids disappears and the
delta C13 stabilized at around-18 parts per thousand. The isotope data indicate
the dynamic nature of the fulvic acid in the peat. The delta D values were around-
60 parts per thousand, but the data are too meager for any firm conclusion.
78:02K-007
THE NATURE OF BASALT WEATHERING IN ISRAEL,
Singer, A.
The Hebrew University of Jerusalem, Israel, Department of Soil and Water Science.
Soil Science, Vol. 125, No. 4, p 217-225, April, 1978. 5 fig, 17 ref.
Descriptors: Weathering, Soil formation, Basalts, Aeolian soils, Saprolites,
Clay minerals, Quartz.
Three major weathering forms of upper Cenozoic basalts are recognized: a weathering
crust, several millimeters thick, at the interface with the massive basalt; a
weathering zone, several centimeters thick, associated with vesicular basalt; and
thoroughly altered basalt saprolite, mostly obtained under prolonged water-saturated
conditions. The clay fractions in the weathering crust and zone consist of smectite
and kaolinite with halloysite, while, in the saprolite, smectite is the only clay
Mineral formed. Si02/A1203 ratios change from 6-7 in the rock to 2-3 in the crust
clay, and this decrease represents maximum desilication obtained under eastern
Mediterranean conditions. With soil development, a resilioation of soil clays
relative to crust clay may take place in the deeper stable profiles. Soil develop-
ment also involves aeolian accumulation of quartz in the coarser size fractions,
and Fe and K enrichment in the clay fraction. Grumusols (Vertisols) represent the
mature, stable end products of basalt weathering on uneroded surfaces in the semi-
arid and subhumid parts of the eastern Mediterranean. In the more humid parts,
Red and Brown Mediterranean soils (Xeralfs) become dominant.
78:Q2K-008
APPLICATION OF THE ELECTRICAL DOUBLE LAYER THEORY TO PREDICT ION ADSORPTION IN
MIXED IONIC SYSTEMS,
Ravina, I., and Gur, Y. . , , .. .
Technion-lsrael Institute of Technology, Haifa, Israel, Faculty of Agricultural
sSiinIcience, Vol. 125, No. 4, p 204-209, April, 1978. 3 fig, 3 tab, 16 ref, 16 equ.
Descriptors: Cation adsorption, Alkali metals, Ions, Hydration, Soil chemistry.
A Poisson-Boltzmann equation including hydration forces and the dielectric saturation
effects for describing the electric double layer was presented and compared with
the Gouy-Chapman theory. Ionic concentrations in the double layer were calculated
by the revised equation showing the specific adsorption of the various alkali metal
cations.
85
-------
78:02K-009
RESIDUAL FORMS OF FERTILIZER NITROGEN IN FIELD SOILS,
Smith, S.J., Chichester, F.W., and Kissel, D.E.
U.S. Agricultural Water Quality Management Laboratory, Durant, Oklahoma.
Soil Science, Vol. 125, No. 3, p 165-169, March, 1978. 1 fig, 2 tab, 17 ref.
Descriptors: Fertilizers, Nitrogen, Chemical analysis, Nitrates, Chemical reactions,
Aerobic conditions, Soil chemistry.
Residual fertilizer N was characterized in Houston Black clay and Keene silt loam
surface soils from recent field microplot-N balance studies involving liberal (328-
560 kg N/ha) 15N-labeled rates. Results indicate residual N is readily distributed
in all_the organic and inorganic soil N forms, even after the first cropping season.
An equivalent distribution of the residual N with the indigenous soil N, however, had
not occurred after three years. During this period the residual N was more than
twice as susceptible to mineralization as the soil N. Most of the residual N was
incorporated in amino acid N-forms.
78:02K-010
MECHANISM OF ZINC ADSORPTION BY IRON AND ALUMINUM OXIDES,
Kalbasi, M., Racz, G.J., and Loewen-Rudgers, L.A.
University of Manitoba, Winnipeg, Manitoba, Canada, Department of Soil Science.
Soil Science, Vol. 125, No. 3, p 146-150, March, 1978. 1 fig, 1 tab, 13 ref.
Descriptors: Adsorption, Zinc, Iron oxides, Aluminum, Ion exchange, Aqueous solu-
tions, Soil chemistry, Hydrogen ion concentration. Chlorides.
Adsorption of Zn from aqueous solutions of ZnC12 by hydrated A1203 and Fe203 was
highly pH-dependent and increased markedly with increasing pH. Fe203 had a higher
Zn adsorption capacity, at equivalent pH values, than A1203. Experimental observations
suggested that surface aqus (-OH2) and hydrono (-OH) groups were involved in Zn ad-
sorption. In addition, experimental observations lead to the postulation that two
types of adsorption, specific and nonspecific, depending upon reversibility (exchange-
ability with Ba(2+)), occurred. Specific and nonspecific adsorptions of Zn(2+) were
accounted for 60 to 90% and 40 to 10% of the total Zn adsorption respectively. For
specific adsorption, an olation bridge structure between Zn(2+) and two surface -OH2
groups was postulated; and for nonspecific adsorption, a single-bond structure in
which ZnCl(+) replaced one H(+)from surface -OH2 groups was postulated. The ratio
of specific to nonspecific adsorption increased with increasing pH. It was concluded
that specific adsorption of Zn by A1203 and Fe203 may be at least partially responsi-
ble for the frequency reported fixation and unavailability of added Zn to soils.
78:02K-011
CHEMICAL CHARACTERIZATION OF LOCAL AND STRATOSPHERIC PLUTONIUM IN OHIO SOILS
Muller, R.N.
Argonne National Laboratory, Argonne, Illinois, Radiological and Environmental Re-
search Division.
Soil Science, Vol. 125, No. 3, p 131-136, March, 1978. 1 fig, b tab, 21 ref, 1 append.
Descriptors: Isotope studies, Chemical analysis, Ecosystems, Industrial wastes, Soil
contamination, Ohio.
The chemical nature of plutonium derived from stratospheric fallout and industrial
sources was studied in three agricultural soils. The majority of the soil plutonium
was associated with a reductant-soluble, hydrous oxide phase that, under most condi-
tions of terrestrial ecosystems, remains essentially immobile. The proportion of
plutonium associated with organic matter (0.1N NaOH-extractable) varied among soils,
and increased with decreasing particle size in the same soil. In a soil containing
238Pu from a local fabrication facility and 239,240Pu from stratospheric fallout,
isotopic ratios between the NaOH-extractable and residual phases were essentially con-
stant, indicating that, in these soils, plutonium from both sources behaves similarly.
The distribution of soil plutonium with particle size appears to be most directly
related to the mass of the soil particle.
86
-------
78-.02K-012
EFFECTS OF TEMPERATURE AND TIME ON HYDROXY ALUMINUM PHOSPHATE-MONTMORILLONITE
COMPLEX,
Webber, M.D.
Soil Research Institute, Agriculture Canada, Ottawa, Ontario KlA OC6.
Soil Science, Vol. 125, No. 2, p 107-114, February, 1978. 3 fig, 3 tab, 16 ref.
Descriptors: Montmorillonite, Aluminum, Phosphates, Clay minerals, Temperature, Time,
Solubility, Suspension, Aerobic conditions, Acidic soils.
Hydroxy aluminum phosphate-montmorillonite complex persisted for 320 days in aqueous
aerobic suspensions that exhibited a pH range of 2.5 to 3 and were maintained at 10,
25, and 35C. There were small changes in its chemical and x-ray diffraction properties
with time, and these occurred more quickly as the temperature was raised. It persisted
for 100 to 200 days at 50C, but then variscite formed and interlayer material dis-
appeared from the clay. Solubility calculations indicated that preparations con-
taining the complex were undersaturated with respect to gibbsite and supersaturated
with gibbsite, but saturated with variscite. Seeding the preparations with variscite
and aging at 25C did not cause variscite to form. It is postulated that amorphous
hydroxy aluminum phosphate, which is an important soil-fertilizer reaction product
and a good source of phosphorus for plants on neutral soil, is likely to persist
indefinitely in temperate acid soils.
78:02K-013
REACTION PRODUCTS AND SOLUBILITY OF APPLIED ZINC COMPOUNDS IN SOME MANITOBA SOILS,
Kalbasi, M., Racz, G.J., and Lewen-Rudgers, L.A.
University of Manitoba, Winnipeg, Manitoba, Canada, Department of Soil Science.
Soil Science, Vol. 125, No. 1, p 55-64, January, 1978. 4 fig, 6 tab, 26 ref.
Descriptors: Zinc, Solubility, Sulfates, Sulfides, Ammonium compounds, Fertilizers,
X-ray diffraction, Calcareous soils, Soil chemistry.
2nS04, ZnEDTA, ZnS, and ZnSO4 plus NH4H2P04 were banded in soils, and the solid-
Phase zinc compounds were identified using x-ray diffraction analysis. Solubility
of zinc in soil adjacent to the fertilizer band was determined by measuring the zinc
concentration in soil-water extracts. The reaction product in a noncalcareous soil
-------
this time and unrecoverable in the NaHCO3 solution upon immediate extraction. Thus,
the labile compounds, like RNA, its four 3' nucleotides, and glycerophosphates were
recoverable in the 0-5M NaHCO3-extracting solution (pH 8.5) of Olsen et al., while
the Na-phytate, a relatively resistant compound, was not. Native Po was only slightly
affected. However, a relatively constant amount of native Po was extracted, irre-
spective of extraction periods lasting 0.5 to 6 h.
78:02K-015
THE BEHAVIOR OF SULPATE ON SALT INPUT IN PODZOLIC BROWN EARTH,
Khanna, P.K., and Beese, F.
Georg-August University, Buesgenweg 2, Goettingen, West Germany, Institute of Soil
Science and Forest Nutrition.
Soil Science, Vol. 125, No. 1, p 16-22, January, 1978. 4 fig, 3 tab, 17 ref.
Descriptors: Sulfates, Salts, Adsorption, Chemical precipitation, Podzols, Effluents*
Leachate, Sorption, Inorganic compounds.
The behavior of sulfate concentration in the leachate of an acid podzolic brown earth
was studied, when a slug of neutral salt (KCl + KN03) passed through the upper
sulfate-enriched layers of the soil. The effluent of five undisturbed soil columns
was collected daily, and H(+), Cl(-), and SO4(—) concentrations were measured. A
constant flux of water, either 1.0 cm/day or 0.3 cm/day, was maintained. Sulfate
concentration in the leachate showed a decrease when the salt passed the columns.
The decrease corresponded with an increase of H(+) and Cl(-) concentrations. The
behavior of sulfate was almost the same irrespective of the flow rates. At the lower
rate, sulfate retention was about twice that at the higher rate. Though precipi-
tation of basic aluminum sulfates cannot be excluded, the behavior of sulfate must
be interpreted in terms of specific adsorption.
78:02K-016
FIELD PERSISTENCE AND MOVEMENT OF TRIFLURALIN IN TWO SOIL TYPES,
Duseja, D.R., and Holmes, E.E.
Tennessee State University, Nashville.
Soil Science, Vol. 125, No. 1, p 41-48, January, 1978. 1 fig, 8 tab, 27 ref.
Descriptors: Herbicides, Weed control, Weeds, Johnson grass, Oats, Movement,
Persistence.
Trifluralin (alpha, alpha, alpha-trifluoro-2, 4, dinitro-N, N-dipropyl-p-toluidine)
was applied in 1973 to Egam load and Season clay field plots. Trifluralin
persistence and movement in both soils was essentially the same, even though higher
herbicide rates were applied to Beason clay, according to manufacturer's recommenda-
tions. There was an increasing trend of herbicide residues with excessive rates of
trifluralin application. The herbicide essentially dissipated from soils in five
months, with only 2.1 percent and 0.4 percent of the initially applied amounts re-
maining in the soil profile, in the Egam and Beason soils, respectively, at the
highest (two times) rate of herbicide application. No herbicide was detected in the
soil the following spring (eleven months after application). Herbicide persistence
could be described by a first-order kinetics. Downward movement of trifluralin
under the conditions of this experiment did occur to the eight in depth; further
penetration of herbicide was essentially nil. Apparently, upward movement of
trifluralin also occurred under these conditions. The control of Johnson grass and
two broadleaf weed species present in the soil lasted from four to five weeks only.
78:02K-017
NITRAPYRIN DEGRADATION AND MOVEMENT IN SOIL,
Touchton, J.T., Hoeft, R.G., and Welch, L.F.
Georgia University, Georgia Station, Experiment, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 5, p 811-816, September-October, 1978. 5 fig, 5 tab,
13 ref.
Descriptors: Nitrification, Inhibitors, Degradation (decomposition), Movement,
Ammonium compounds, Ammonia, Fertilizers, Soil chemical properties, Soil physical
properties.
88
-------
Nitrapyrin [2-chloro-6-(trichloromethyl)pyridine] is applied with ammonium-N
fertilizers to control nitrification in soil. However, little information is avail-
able on the persistence or loss of field-applied nitrapyrin. The objective of this
study was to monitor movement and degradation of nitrapyrin in soil. Nitrapyrin
was applied with anhydrous ammonia in the fall of 1975 and spring of 1975 and 1976.
Measurable quantities of nitrapyrin were not found beyond 7.5 cm from the point of.
release in the soil. The distance that nitrapyrin moved from the point of release
in the soil was not affected by nitrapyrin rates. Greater nitrapyrin movement was
not detected in one direction from the point of release in the soil than in another
direction. Increasing rates of anhydrous ammonia had no effect on nitrapyrin movement
of degradation. The most rapid rate of degradation occurred soon after application
and decreased with time. The data suggest that nitrapyrin degradation and movement
will depend on the physical and chemical characteristics of the soil. Even though
degradation rates decreased with time, no indication was found to prove that soil
accumulations of nitrapyrin will result from once-a-year applications.
78:02K-018
EFFECT OF NITRAPYRIN ON NITRIFICATION OF FALL AND SPRING-APPLIED ANHYDROUS AMMONIA,
Touchton.. .T.T., Hoeft, R.G., and Welch, L.F.
Illinois University, Urbana, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 5, p 805-810, September-October, 1978. 5 fig, 5
tab, 15 ref.
Descriptors: Nitrification, Inhibitors, Denitrification, Nitrates, Fertilizers,
Ammonia, Leaching, Timing, Rates of application, Soil types.
Nitrification of ammonium fertilizers in late fall and early spring and subsequent
nitrate losses through leaching and denitrification are a continuing economical
and environmental concern. To evaluate the effects of nitrapyrin on nitrifica-
tion, anhydrous ammonia with and without nitrapyrin was applied in the fall and
spring to poorly drained soils. Nitrogen and nitrapyrin rates ranged from 0 to
268 and 0 to 1.12 kg/ha, respectively. Detailed sampling from ammonia retention
zones was conducted throughout the fall, spring, and summer. Effects of nitra-
pyrin on nitrification varied with time of application, nitrapyrin rate, and
soil type.
78f02K-019
NITROGEN RELEASE CHARACTERISTICS OF ISOBUTYLIDENE DIUREA AND ITS EFFECTIVENESS
AS A SOURCE OF N FOR FLUE-CURED TOBACCO,
Miner, G.S., Lilly, J.P., and Terry, D.L.
North Carolina State University, Raleigh, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 3, p 434-438, May-June, 1978. 3 fig, 3 tab, 12
ref.
Descriptors: Nitrogen, Leaching, Tobacco, Nutrient removal. Fertilizers, Parti-
cle size.
The objectives of this study were to investigate the release characteristics of
isobutylidene diurea (IBDU), with N-release characteristics dependent primarily
upon the effects of particle size on chemical dissolution rather than the effects
of environmental variation on biological activity, in laboratory and greenhouse
studies and to evaluate it as a source of N for flue-cured tobacco in the field.
Urea, NaN03, and four particle sizes of IBDU (1.05, 0.75, 0.55, and 0.40 mm) were
applied at rates of 200 and 400 mg N per kg of soil to a Norfolk sandy loam
(Typic paleudult) in lysimeters and subjected to leaching at ten intervals over
a 109-day period. Percentage removal of N from these sources were observed at a
different leaching time. The effects of particle size of IBDU on dry matter and
N uptake were studied to determine their N release characteristics. IBDU parti-
cle sizes of 1.05 and 0.40 mm were compared with NaN03 and Urea as N sources for
flue-cured tobacco.
78:02K-020
FATE OF FERTILIZER NITRATE APPLIED TO COASTAL BERMUDAGRASS ON A SWELLING CLAY SOIL,
Kissel, D.E., and Smith, S.J.
Texas Agricultural Experiment Station, Temple, Blackland Research Center.
Soil Science Society of America Journal, Vol. 42, No. 1, p 77-80, January-
February, 1978. 3 tab, 16 ref.
89
-------
Descriptors: Nitrates, Denitrification, Fertilizers, Bermudagrass, Soil physical
properties.
The disposition of N fertilizer applied to Coastal bermudagrass in the field over
two growing seasons was determined by applying 560 kg N/ha as Ca(N03)2 tagged with
7.599 atom % 15N to a field microplot during 1974 and measuring various components
of the N balance. Plant uptake of residual N was measured during 1975. Forty-nine
percent of the applied N was recovered in harvested forage in 1974. About 40% of the
applied N remained in the soil as residual N at the end of 1974. About 10% of
N was unaccounted for, indicating that denitrification losses were no more than
10% of the applied N. Most of the residual N at the end of the first growing
season was immobilized N or was present in the root system of the grass. Immobili-
zation is, therefore, a major factor causing low recovery of applied N by Coastal
bermudagrass on swelling clay soils. Moreover,-since only 17% of the residual
N was recovered in forage during 1975 (7% of the N applied in 1974) , most of
the immobilized N was not available the following year.
78:02K-021
IMPORTANCE OF THE ORGANIC PHOSPHORUS FRACTION IN EXTRACTS OF CALCAREOUS SOIL,
Abbott, J.L.
Cotton Research Center, 4201 E. Broadway, Phoenix, Arizona 85040.
Soil Science Society of America Journal, Vol. 42, No. 1, p 81-85, January-February,
1978. 2 fig, 8 tab, 10 ref.
Descriptors: Soil analysis, Calcareous soils, Phosphorus, Forage sorghum, Ferti-
lizers, Organic compounds, Soil chemistry.
Laveen clay loam soil samples were collected immediately following the harvest
of forage sorghum (Sorghum bicolor (L.) Moench). Two sets were prepared before
growing turnips (Brassico rapa L.) as the test crop in the greenhouse. One set
was without treatment and the other, to simulate winter and spring conditions,
was incubated for twenty days after addition of N and dextrose. Phosphorus uptake
by turnips and changes in soil P forms were positively correlated with correspond-
ing measurements taken during the growth of the sorghum crop. Correlations
among P uptake by forage sorghum, turnips, and soil P measurements indicated
their value in predicting available P. Prediction values for two of the procedures
were improved by including the extractable organic P with the inorganic P for the
incubated soil. Results showed that (1) time of sampling, (2) the crop to be
grown, (3) the method of extraction, and (4) the means of converting organic P
to a measurable inorganic form in the extract are of prime concern in deciding
when to include extractable organic P in the P evaluation of a given soil.
78:02K-022
MINERALIZATION, IMMOBILIZATION AND NITRIFICATION,
Broadbent, F.E.
California University, Davis, Department of Land, Air and Water Resources.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 109-134, May 15-18,
1978. 5 fig, 3 equ, 33 ref.
Descriptors: Nitrogen, Nitrification, Ammonia, Decomposing organic matter, Soil
microorganism, Inorganic compounds, Pollutants, Inhibitors.
The decomposition of organic substances containing nitrogen through the acti-
vities of soil microorganisms and resulting in the release of some of the nitro-
gen as ammonia is called nitrogen mineralization. Net mineralization occurs when
the quantity of nitrogen in the material undergoing decomposition exceeds the
needs of the microbial population for nitrogen to produce new cells. If the
decomposing substances do not contain enough nitrogen to meet the needs of the
microbial population, any inorganic nitrogen present in the soil will be utilized
by the microbes and converted to cell protein and other nitrogenous compounds.
This process is called immobilization. In a sense the assimilation of inorganic
nitrogen by growing plants is also immobilization, but this discussion considers
only the microbiological process. The nitrogen supplying capacity of soils
depends to a large extent on rates of mineralization and immobilization. Various
procedures have been utilized to obtain estimates of nitrogen mineralization
over a growing season, the most successful of which have been based on incubation
90 "
-------
of soil samples under controlled conditions for a few weeks. Desirable management
practices should favor not only efficient utilization of fertilizer nitrogen,
but also maximum crop uptake of mineralized, nitrogen. Experiments with isotopi-
cally labeled fertilizers indicate that these two objectives are compatible
with each other and also with the need to minimize leachable nitrate.
78:02K-023
SIMULATION OF NUTRIENT LOSS FROM SOILS DUE TO RAINFALL ACIDITY,
Reuss, J.O.
Environmental Research Laboratory-Corvallis, Corvallis, Oregon, Office of Research
and Development, United States Environmental Protection Agency.
Publication No. EPA-600/3-78-053, May, 1978. 45 p, 12 fig, 4 tab, 18 ref.
Descriptors: Rainfall, Water analysis, Water chemistry, Soil science, Soil
chemistry, Plant nutrition, Ecology.
This paper describes a simulation model that provides a quantitative system uti-
lizing established relationships from soil chemistry to predict the most likely
effect of rainfall acidity on the leaching of cations from noncalcareous soils.
The model utilizes the relationships between lime potential (pH - l/2pCa) and
base saturation described by Clark and Hill (Soil Sci. Soc. Amer. Proc. 28:490-
492, 1962) and Turner and Clark (Soil Sci. 99:194-199, 1964), the equilibrium
between CO2 partial pressure and H+ and HCO3- in solution, the apparent solubi-
lity product of AL(OH)3, the equilibrium of cations and anions in solution, the
Freundlich isotherm description of ions between the solution and sorbed or ex-
changeable phases. Ionic composition of leachates in response to rainfall
composition can thus be computed. Ions considered in the present version are
H+, Ca2+, A13+, S042-, CL-, and HC03-. The model predicts almost exact chemical
equivalence between basic cation removed in the leachate and strong acid anions
entering the system in the rainfall of pH - l/2pCa is above 3.0, at which point
the base saturation will generally not exceed 20%. At lower pH - l/2pCa values
leaching of anions in association with H+ and A13+ becomes significant and these
cations predominate when pH - l/2pCa falls below 2.0.
78:02K-024
MULTICOMPONENT CATION ADSORPTION DURING CONVECTIVE-DISPERSIVE FLOW THROUGH SOILS:
EXPERIMENTAL STUDY,
Lai, s-H., Jurinak, J.J., and Wagenet, R.J.
Utah State University, Logan, Department of Soils and Biometeorology.
Soil Science Society of America Journal, Vol. 42, No. 2, p 240-243, March-April,
1978. 5 fig, 14 ref, 2 equ.
Descriptors: Cation adsorption-, Cation exchange, Soil water movement, Solutes,
Sodium, Magnesium, Calcium, isotherms.
The adsorption of H(+), Mg(2+), and Ca(2+) from aqueous solutions flowing through
soil was examined under different total cation concentrations and input pulse
volumes. The pulses of H(+) and Mg(2+), which were introduced into a Ca(2+)-
saturated Yolo loam soil column, appeared separately in the effluent. The degree
of separation decreased with total concentration, but was not affected signifi-
cantly by the pulse volume. At constant total concentration, the initial
appearance of the Mg(2+) pulse was delayed with increasing pulse volume. The
experimental results were compared to theoretical calculations based on a single
component linear equilibrium model. At a low loading (a small amount of adsorb-
ate with respect to a large amount of adsorbent), the agreement of the theoreti-
cal model and the experimental results was satisfactory. However, when the
loading was increased, the discrepancy between the calculated values and the
experimental results increased.
78:02K-025
ADSORPTION OF ALDICARB BY CLAYS AND SOIL ORGANO-CLAY COMPLEXES,
Supak, J.R., Swoboda, A.R., and Dixon, J.B.
Texas A&M University, College Station, Department of Soil and Crop Science.
Soil Science Society of America Journal, Vol. 42, No. 2, p 244-248, March-April,
1978. 3 fig, 3 tab, 22 ref.
91
-------
Descriptors: Carbamate pesticides, Systemics, Insecticides, Adsorption, Illite,
Montmorillonite, Kaolinite, Clay minerals.
Adsorption experiments conducted with S-methyl-14C-aldicarb resulted in what
appeared to be negative adsorption (exclusion) of the toxicant on Ca- and Al-
saturated montmorillonite clays. Calculated exclusion volumes indicated that
aldicarb did not penetrate the interlamellar region. Aldicarb was excluded from
at least the first 16 layers of water on external surfaces of montmorillonite.
Positive adsorption occurred with Ca- and Al- saturated illite and kaolinite
clays. Equilibration of aldicarb solutions with one acid and two calcareous
Vertisols, and with the organo-clay complexes isolated from these Vertisols,
produced negative adsorption isotherms for the acid and positive adsorption iso-
therm for calcareous adsorbents.
78:02K-026
POTASSIUM AND RUBIDIUM ADSORPTION AND DIFFUSION IN SOIL,
Baligar, V.C., and Barber, S.A.
Guelph University, Ontario, Canada, Department of Land Resource Science.
Soil Science Society of America Journal, Vol. 42, No. 2, p 251-254, March-
April, 1978. 2 fig, 4 tab, 10 ref, 6 egu.
Descriptors: Cation adsorption, Cation exchange, Potassium, Cations, Diffusion,
Correlation analysis, Organic matter.
The adsorption of K and Rb by four soils was investigated to determine the
differences in adsorption of K and Rb which may occur and how they are affected
by soil properties with the view of using this information to evaluate the in-
take mechanisms for K and Rb by plant roots" growing in soil. Rubidium was
adsorbed preferentially to K by all four soils. Selectivity coefficient k sub
Rb/K, indicating the size of the effect ranged from 1.9 to 4.4. Adding K
decreased k sub Rb/K, increased the amount of nonexchangeable Rb and decreased
exchangeable Rb. There was a negative correlation (coefficient of determination
= 0.78) between exchangeable K in the soil and k sub Rb/K. The level of K in
the soil had a greater effect on k sub Rb/K than varying types of exchange sites
present due to differences in clay and amounts of organic matter in the four
soils investigated. The size of the selectivity coefficient'indicated that the
difference between K/Rb ratios in the solution and exchange phases of these soils
used and differences between soils made them suitable for use in plant uptake
studies of the mechanisms of K and Rb uptake.
78:02K-027
THE DISTRIBUTION OF MICRONUTRIENT CATIONS IN SOIL UNDER CONDITIONS OF VARYING
REDOX POTENTIAL AND pH",
Sims, J.L., and Patrick, W.H., Jr.
Kentucky University, Lexington, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 2, p 258-262, March-April,
1978. 5 tab, 19 ref.
Descriptors: Iron, Manganese, Zinc, Copper, Organic matter, Nutrient removal,
Flooding, Toxicity.
A laboratory study was conducted to determine the influence of redox potential
and soil pH on the distribution of Fe, Mn, Zn, and Cu in Mhoon silty clay loam
soil (Typic Fluvaguents) and to provide insight into factors affecting micro-
nutrient dissolution and mobility in soil. Generally, greater amounts of Fe, Mn,
Zn, and Cu were found in the Na acetate (exchangeable) and pyrophosphate (organic)
extractions at low pH and Eh than at high pH or Eh. In contrast, the amounts
(except Mn) in the water-soluble, NH2OH-HC1, and oxalate fractions were greater
at high pH or Eh. Although the micronutrients were brought into solution at
low pH and Eh, much of the soluble cations soon associated with the exchange-
able and organic fractions. After reduction, mobilized Fe associated about
equally with the exchangeable, organic, and NH20H-HC1 fractions; immobilized Mn
with the exchangeable and water-soluble fractions; mobilized Zn with the organic
fraction; and the mobilized Cu with the organic and water-soluble fractions.
Separation of the water-soluble fraction into free ions and those complexed by
soluble organic matter indicated that micronutrient cations were complexed by
organic matter to a greater extent in reduced soil.
92
-------
78:02K-028
DETERMINING SOIL GYPSUM CONTENT AND EXPRESSING PROPERTIES OF GYPSIFEROUS SOILS,
Nelson, R.E., Klameth, L.C., and Nettleton, W.D.
National Soil Survey Laboratory, Lincoln, Nebraska, Soil Conservation Service.
Soil Science Society of America Journal, Vol. 42, No. 4, p 659-661, July-August,
1978. 1 fig, 2 ref, 18 egu.
Descriptors: Gypsum, Sulfates, Soil water, Soil chemical properties, Soil tests,
Soil chemistry.
The standard method for measuring the gypsum content of soils is a lengthy one,
partly because of the presence of Na and Mg sulfates in most gypsic horizons,
and partly because of the difficulty in dissolving all the gypsum in the sample.
A more rapid method, sufficiently accurate for taxonomic uses, has been developed
and is based on loss of crystal water of gypsum upon heating to 105 C. Percent
gypsum, calculated on an oven-dry weight basis from loss of crystal water,
equals 1.038 x percent gypsum by the standard chemical method + 0.17. The
standard error of estimate for the new methods is + 1.8% gypsum. Equations are
given for expressing properties of gypsiferous soils on an oven-dry + crystal
water of gypsum weight basis.
78:02K-029
THE ACETYLENE INHIBITION METHOD FOR SHORT-TERM MEASUREMENT OF SOIL DENITRIFICATION
AND ITS EVALUATION USING NITROGEN-13,
Smith, M.S., Firestone, M.K., and Tiedje, J.M.
Michigan State University, East Lansing, Department of Crop and Soil Sciences.
Soil Science Society of America Journal, Vol. 42, No. 4, p 611-615, July-August,
1978. 1 fig, 6 tab, 11 ref.
Descriptors: Denitrification, Inhibitors, Nitrogen, Reduction (chemical),
Anaerobic conditions, Aerobic treatment.
Acetylene was found to effectively inhibit the reduction of N20 by anaerobic
soils. With concentrations of C2H2 above 0.1 atm, added N03(-) was quantita-
tively converted to N2O and added N2O was reduced at an insignificant rate.
Experiments with 13N demonstrated that at low soil nitrate concentrations at
least 0.1 atm C2H2 was required for effective inhibition. Denitrification rates
determined by 13N and by C2H2 inhibition methods correlated well, as did deter-
mination of N2O/(N2 + N2O). The methods also revealed that an acceleration in
denitrification rate occurred within a few hours after soil was exposed to
anaerobic conditions. The acetylene method was generally used to measure deni-
trification rates in soils incubated as anaerobic slurries, but was also used
to determine rates for field moist aggregrates incubated anaerobically and
aerobically. When assayed as anaerobic slurries, initial denitrification rates
ranged from 0.1 to 0.7 mmoles N gas/soil/min for the mineral soils examined.
The denitrification rate in aerobic aggregrates was approximately 1,000 times
less, showing the strong inhibitory effect of 02 on the indigenous denitrifying
enzymes.
78j02K-030
THE MECHANISM OF SULFATE ADSORPTION ON IRON (OXIDES,
Parfitt, R.L., and Smart, R. St. C.
Griffith University, Nathan. 4111, Queensland, Australia, School of Science.
Soil Science Society of America Journal, Vol. 42, No. 1, p 48-50, January-
February, 1978. 5 fig, 2 tab, 17 ref.
Descriptors: Sulfates, Adsorption, Iron oxides, Isotherms, Spectroscopy,
Structural models, Soil chemistry.
Adsorption isotherms were determined for sulfate adsorption on iron oxides under
acid conditions. The product of the surface reaction between the iron oxides
and sulfate ions was examined by infrared spectroscopy which showed four bands
in the upsilon S-O stretching region. Thus a structural model could be obtained
for the reaction. Two surface hydroxyl groups (or OH2(+) ions) are replaced by
one sulfate ion, and two oxygen atoms of the sulfate ion are coordinated each
to a different Fe(3+) ion, resulting in the binuclear bridging surface complex
Pe-o-S(O2)-0-Fe. The complex is formed on the surfaces of goethite (alpha-FeOOH) ,
93
-------
akaganeite (beta-FeOOH), lepidocrocite (gamma-FeOOH), hematite (alpha-Fe2O3) and
amorphous ferric hydroxide.
78:02K-031
POTENTIAL USE OF FINELY DISINTEGRATED IRON PYRITE IN SODIC AND IRON-DEFICIENT
SOILS r
Vlek, P.L.G., and Lindsay, W.L.
Colorado State University, Fort Collins, Department of Agronomy.
Journal of Environmental Quality, Vol. 7, No. 1, p 111-114, January-March, 1978.
3 fig, 3 tab, 15 ref.
Descriptors: Pyrite, Oxidation, Sulfur, Fertilizers, Mine wastes, Soil amendments,
Colorado.
The rate of chemical oxidation of iron pyrite in water was measured as a function
of particle size. Reducing the particle size greatly increased the rate of oxi-
dation. For pyrite > 250 microns, the PH of the solution leveled off at 5
after six hours while the clay size pyrite dropped to pH4 within twenty-four
hours. in these studies, pyrite was applied at 1% initially with an additional
1% after one month to a slightly sodic, iron-deficient, loamy sand soil from
Colorado. The soil/water ratio was 1:2. When clay size pyrite was used, the
pH of the soil decreased from 8.3 to 7.8 after 1 mo and to 5.7 after 2 mo The
coarser pyrite decreased the PH only slightly. No significant change in the
composition of exchangeable ions occurred during the first month, but the composi-
tion had changed sufficiently after 2 mo to flocculate the clay The DTPA-
extractable iron increased from 1.5 to 64 PPm for the finest pyrite treatment
during 1 mo, copper double, and manganese quadrupled during this period. Finely
disintegrated pyrite may be useful for reclaiming slightly sodium-affected soils
or for providing slow release available iron.
78:O2K-032
PHOSPHATE ADSORPTION-DESORPTION CHARACTERISTICS OF SOILS AND BOTTOM SEDIMENT IN
THE MAUMEE RIVER BASIN OF OHIO,
McCallister, D.L., and Logan, T.J.
Texas A & M University, College Station, Department of Agronomy
Journal of Environmental Quality, Vol. 7, No. 1, p 87-92, January-March, 1978.
z rig, 6 tab, 27 ref.
Descriptors: Adsorption, Eutrophication, Pollutants, Phosphates, Runoff, Isotherms.
Langmuir adsorption isotherms showed that Maumee River Basin sediments had
adsorption capacities 10 to 20 times greater than Basin soils. Although the
soil clay fractions had adsorption capacities higher than the whole soil, they
were considerably less than those of the sediments and the difference is attri-
buted to the higher content of amorphous or low-range order iron and aluminum
components in the bottom sediments. Equilibrium phosphorus concentration (EPC)
and phosphorus desorbed was similar for soil and sediments as well as total P
indicating that although the bottom sediments have a high capacity to adsorb P,
this capacity has not been realized. Correlations between adsorption-desorption
parameters and soil/sediment properties are presented. Bray PI "available" P
was highly correlated with EPC and P desorbed in the soils but to a lesser
extent in the bottom sediments. CDB and oxalate extractable-P was highly cor-
related with P adsorption capacity in the bottom sediments but not in the soils.
78:02K-033
MICROBIAL ASPECTS OF THE VOLATILE LOSS OF APPLIED MERCURY (II) FROM SOILS
Landa, E.R. '
Oregon State University, Corvallis, Department of Soil Science and Agricultural
L-il clnl S T^2Ty •
Journal of Environmental Quality, Vol. 7, No.1, p 84-86, January-March, 1978.
1 fig, 1 tab, 21 ref.
Descriptors: Autoclaves, Mercury, Volatility, Microbial degradation, Soil
amendments, Montana.
94
-------
Five surface soils from southeastern Montana were studied to determine the
effects of autoclaving and glucose additions on the volatile loss of applied
divalent inorganic mercury. Soils were amended to 1 ppm Hg as 203 Hg - Hg
(N03)2, maintained at room temperature near the 1/3-bar moisture content, and
Hg content monitored for seven weeks. Mercury losses from soils receiving
neither autoclaving or glucose additions ranged from 5 to 30%. In general,
autoclaving reduced the total quantity of Hg lost, while glucose additions
increased the initial loss rate of applied Hg.
78:02K-034
COPPER AND CADMIUM ADSORPTION CHARACTERISTICS OF SELECTED ACID AND CALCAREOUS
SOILS,
Cavallaro, N., and McBride, M.B.
Cornell University, Ithaca, New York, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 4, p 550-556, July-August,
1978. 9 fig, 2 tab, 27 ref.
Descriptors: Heavy metals, Copper, Cadmium, Adsorption, Ion exchange, Acidic
soils, Calcareous soils, Soil chemistry, New York.
Samples of two New York soils, an acid and a neutral silt loam, were equilibrated
with Cu(2+) and Cd(2+) solutions in concentrations ranging from 0.00001 to 0.0001M
in distilled water and in 0.01M CaCl2. The extent of complexation and adsorption
of the heavy metals was measured using specific ion electrodes and atomic absorp-
tion. The data were found to fit the Langmuir adsorption model, and the Cu(2+)
adsorption maxima were greater than those of Cd(2+) for both soils. Acid soils
demonstrated much less ability to retain the heavy metals than neutral soils.
In the presence of 0.01M CaCl2, adsorption of the metals was much reduced, suggest-
ing Ca(2+) competition for adsorption sites. A considerable amount of Cu(2+)
was complexed in the soil solutions, but Cd(2+) complexation was much less evident.
The results support an ion exchange mechanism of adsorption in the surface soils,
arid suggest that precipitation occurs in calcareous subsoils.
78:02K-035
THERMODYNAMICS OF POTASSIUM-CALCIUM AND MAGNESIUM-CALCIUM EXCHANGE REACTIONS ON A
KAOLINITIC SOIL CLAY,
Udo, E.J.
Ibadan University, Nigeria, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 4, p 556-560, July-August,
1978. 2 fig, 3 tab, 22 ref, 15 equ.
Descriptors: Thermodynamics, Cation exchange, Kaolinite, Potassium, Calcium,
Magnesium, Adsorption, Isotherms, Selectivity, Soil profiles.
Thermodynamic parameters derived from experimental results were determined for the
potassium-calcium and magnesium-calcium exchange reactions on a kaolinitic soil
clay separated from the B horizon of a strongly weathered soil Profile. The clay
samples were equilibrated at 10 and 30 C with a mixed solution of KCl and CaC12
for the K-Ca system or MgCl2 and CaCl2 for the Mg-Ca system. For the K-Ca system,
the selectivity coefficients were high indicating a greater affinity of the clay
for K than for Ca. The high equilibrium constant and the negative values of
standard free energy and enthalpy changes for the exchange of Ca for K also revealed
a preference of the clay for K relative to Ca ions. In the Mg-Ca system, the
exchange isotherms and the low selectivity coefficients indicated a preference of
Ca ions for the clay phase. This exchange of Ca for Mg was accompanied by an in-
crease in the free energy and enthalpy changes also pointing to a more stable Ca-
clay than Mg-clay.
78:02K-036
PREDICTION OF PHOSPHORUS DIFFUSION FROM FERTILIZER SOURCE,
Hira, G.S., and Singh, N.T. . .,
Punjab Agricultural University, Ludhiana, India, Department of Soils.
Soil science Society of America Journal, Vol. 42, No. 4, p 561-565, July-August,
1978. 7 fig, 2 tab, 11 ref, 11 equ.
Descriptors: Phosphorus, Diffusion, Fertilization, Diffusivity, Adsorption,
Isotherms, Soil chemistry.
95
-------
Rate of P diffusion from fertilizer applied at the soil surface was studied using
Pick's law of diffusion. The diffusion coefficient of P was determined from a
knowledge of the tortuosity factor and P adsorption isotherm. Phosphorus diffu-
sion coefficient calculated from Nye's equation did not prove suitable at very
low or high concentration of P at the soil surface. The phosphorus diffusion
coefficient calculated from experimental data increased linearly with the square
root of P concentration applied at the source. Predicted P concentration-distance
profiles were very close to the experimental values estimated by employing a
sectioning technique.
78:02K-037
PHOSPHATE DESORPTION FROM KAOLINITE SUSPENSIONS,
Bar-Yosef, B., and Kafkafi, U.
Division of Soil Chemistry and Plant Nutrition, Bet Dagan, Israel, The Volcani
Center.
Soil Science Society of America Journal, Vol. 42, No. 4, p 570-574, July-August,
1978. 5 fig, 2 tab, 18 ref, 2 equ.
Descriptors: Phosphates, Kaolinite, Activation energy, Hysteresis.
The objective of this work was to study the effect of the .desorption method used,
equilibration time and the dissolved silica on the desorption of P from kaolinite.
Two desorption methods were used: (i) diluting 1% suspensions by various volumes
of the same electrolyte,-arid (ii) immersing a dialysis tube containing 0.25%
suspension (+P) in an identical suspension initially free of P. The desorption
process in both cases could be divided into a rapid and a slow first-order
reaction. The rapid reaction rate constant was similar in both systems (about
4.65 x 0.001/hour at 25 C). The slow reaction constants were 0.3 x 0.001/hour and
1.15 x 0.001/hour for cases (i) and (ii) , respectively. The activation energy of
the desorption process in case (ii) was 16.2 Kcal/mole for the rapid and 4.8 Real/
mole for the slow reaction. The amount of silica dissolved from kaolinite due to
dilution with 0.01M KC1 depended on the dilution ratio and reached 16 mg SiO2/g
kaolinite when the suspension was diluted 100-fold. Readsorption of part of the
dissolved silica is stipulated to contribute to the fast P desorption process.
78:02K-038
FACTORS AFFECTING DENITRIFICATION IN A SONORAN DESERT SOIL,
Westerman, R.L., and Tucker, T.C.
Oklahoma State University, Stillwater, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 4, p 596-599, July-August,
1978. 4 fig, 3 tab, 6 ref.
«
Descriptors: Denitrification, Nitrogen, Temperature, Moisture content, Time, Arid
climates, Deserts, Carbon, Depth. ',
Incubation studies were conducted to determine the effect of temperature, moisture
content, organic C, soil depth, and time on transformations of added 15NO3(-N) to
a Sonoran Desert soil in open and closed systems. In open system studies, increasing
temperature from 20 to 37 C, adding organic C, and increasing moisture content from
field capacity to saturation increased denitrification losses 16, 22, and 2%,
respectively. There were no apparent differences in immobilization of 15N03(-N)
due to temperature, time, moisture content, or soil depth without organic C'amend-
ments. However, immobilization of 15N03C-N) soil with organic C amendments was
increased markedly with increased temperature and time, but initial moisture con-
tent had little effect. At C/N ratios of 150:1 only traces of 15N appeared in
NH4(-N), however, at C/N ratios of 15:1 to 45:1 ammonification and immobilization
occurred simultaneously. Closed system investigations with organic C and 15N03(-N)
amendments showed 79% loss in five days with the remaining 21% accumulating as
organic-15N. Denitrification losses in open systems with soil moisture contents
representative of saturated conditions were 70% of the loss observed under closed
systems at the same moisture content.
96
-------
78:02K-039
SURFACE CHARGE MANIPULATION OF CONSTANT SURFACE POTENTIAL SOIL COLLOIDS: I
RELATION TO SORBED PHOSPHORUS,
Warm, S.S., and Uehara, G.
Hawaii University, Honolulu, Department of Agronomy and Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 4, p 565-570, July-August
1978. 7 fig, 4 tab, 20 ref, 7 equ.
Descriptors: Colloids, Phosphorus, Cation adsorption, Cation exchange, Soil
management, Soil chemistry.
A significant correlation was found between the zero point of charge and the
quantity of phosphorus applied to soil material from an Oxisol. Sorbed phosphorus
lowered the zero point of charge and increased surface charge density at any pH
above the zero point of charge. The soil was treated with 0, 100, 500, and 1,500
Ppm P as (NH4J2HPO4. For the soil with no added phosphorus, low concentration
of monovalent electrolyte and within two pH units of the zero point of charge,
diffuse layer theory adequately predicted surface charge. For high electrolyte
concentration and high pH, the Stern theory with specific adsorption energy
predicted the experimental results. The calculated results indicated charge
reversal in the high-phosphorus samples.
78:02K-040
EFFECTS OF SOLUTION CHEMISTRY AND ENVIRONMENTAL CONDITIONS ON AMMONIA VOLATILIZATION
LOSSES FROM AQUEOUS SYSTEMS,
Vlek, P.L.G., and Stumpe, J.M.
International Fertilizer Development Center, Florence, Alabama, Agro-Economic
Division.
Soil Science Society of America Journal, Vol. 42, No. 3, p 416-421, May-June, 1978.
5 fig, 1 tab, 17 ref, 7 equ.
Descriptors: Nitrogen, Ammonia, Volatility, Rice, Fertilization, Aqueous solutions,
Kinetics.
Laboratory studies were conducted to explain the wide variation in reported esti-
mates of ammonia volatilization losses from N-fertilized paddy fields. The ammonia
volatilization capacity of a system was found to be equivalent to its alkalinity.
In solutions lacking alkalinity, loss of (NH4)2SO4 was limited, whereas loss of
(NH4)2C03 was essentially complete. Ammonia loss from solution is best described
as a consecutive reaction with opposing step. Ammonia volatilization per se
followed first-order reaction kinetics. The rate of ammonia volatilization was
severely restricted by limiting the movement of air above the water, as is often
the case in the laboratory and field studies reported to date. Ammonia volatili-
zation was enhanced by water turbulence and increased exponentially with temperature
from almost nil at 0 C to approximately 20 mg N/100 sq cm/5 hours at 46 C.
78:02K-041
CALCIUM-SUPPLYING CHARACTERISTICS OF TWO GYPSUM MATERIALS ON SOUTHEASTERN COASTAL
PLAIN SOILS,
Keisling, T.C., and Walker, M.E.
Texas A & M University, Overton, Agricultural Research and Extension Center.
Soil Science Society of America Journal, Vol. 42, No. 3, p 513-517, May-June, 1978.
2 fig, 2 tab, 16 ref.
Descriptors: Gypsum, Calcium sulfate, Peanuts, Granules, Leaching, Particle size,
Coastal plains.
Field studies were conducted on two soils to study the manner in which finely and
coarsely divided gypsum materials supplied Ca to the soil depth where peanut
(Arachis hypogaea L.) fruit absorb Ca. The finely divided material was charac-
terized chemically as CaS04-2H20, approximately 72% CaS04 or 20.2% Ca and physically
as having 88% of the particles < 0.25 mm in diameter. The coarsely divided material
was characterized chemically as CaSOR, approximately 92% CaS04 or 26.5% Ca and
Physically as having 82% with particle diameters < 4.2 mm, but > 0.5 mm. The
amount of Ca transported to a given soil depth was found to be related to the
n^agnitude, order, and frequency of rainfall events. The fine gypsum material was
found to be more effective in supplying Ca to the soil depth where peanut fruit
97
-------
are absorbing it early in the growing season than the coarser material. Dissolu-
tion of gypsum sources consisting of different particle sizes and subsequent
transport of Ca into the fruiting zone of peanuts was not always closely related
to the total amount of rainfall. Either the finely or coarsely divided gypsum
could supply more Ca to the fruiting zone depending on the rainfall pattern.
78:02K-042
COMETABOLISM OF FOREIGN COMPOUNDS,
Golovleva, L.A., and Skryabin, G.K.
Institute of Biochemistry and Physiology of Microorganisms.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
P 73-85. 6 fig, 11 ref.
Descriptors: Microbial degradation, Soil microbiology, Microorganism, Soil
microorganism, Herbicides, Chemical degradation, Environmental control.
The fermentative conversions of many organic substances are closely connected or
even depend on oxidation of other compounds—cosubstrates. This dependence is
generally called cometabolism. The best known are the cometabolism processes of
foreign compounds—xenobiotics, though there are also the examples of cometabolism
of natural compounds for instance steroids and terpenes as well as such substrates
as xylose, widely spread in nature and easily metabolized. The investigations
conducted by the authors proved that conversions of many xenobiotics are possible
only under cometabolism conditions. The experiments with introduction of micro-
organisms into natural water reservoirs did not give positive results. However,
the degradation of herbicides was significantly accelerated after introducing
cosubstrates. So, analysis of 2,4-D dynamics in waste waters of rice fields has
shown that 2,4-D disappeared more quickly if propionate was used as cosubstrate.
In this case, the herbicide was not detected in the water in three days; at the
same time, about 25% of initial 2,4-D was present in control experiments (without
propionate).
78:02K-043
AMMONIA VOLATILIZATION LOSSES FROM FLOODED RICE SOILS,
Mikkelsen, D.S., De Datta, S.K., and Obsemea, W.N.
The International Rice Research Institute, Los Banos, Laguna, Department of
Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 5, p 725-730, September-
October, 1978. 8 fig, 10 ref.
K
Descriptors: Nitrogen, Volatility, Hydrogen ion concentration, Diurnal, Ammonia,
Submerged plants, Fertilization.
The pH of the flood water in rice fields is largely determined by the chemical
equilibria that exist between the C02 balance achieved by the aquatic biota and
the various solutes, solids, and gases in the water. Water pH values undergo
diurnal changes increasing by midday to values as high as pH 9.5-10 and decreasing
as much as 2-3 pH units during the night. The pH of shallow flood water is greatly
affected by the total respiration activity of all the heterotrophic organisms and
the gross photosynthesis of the species present. Ammonium from fertilizers broad-
cast into a high pH water are highly susceptible to direct NH3 volatilization
losses. Nitrogen losses from fertilizer broadcast into flood water on a fertile,
neutral-pH Maahas clay were as high as 20% of the amount applied, but losses varied
depending upon water pH, the nitrogen source, rate, time, and method of applica-
tion. Losses from an acid Luisiana clay, where the flood water was not conducive
to algal growth and did not exceed pH 6.8, produced NH3 volatilization losses
consistently less than 1% of the total N applied. Placement of N fertilizer in
the soil at depths of 10-12 cm reduced NH3 volatilization losses to less than
1% of the total N applied.
78:02K-044
CHEMISTRY OF SNOW MELTWATER: CHANGES IN CONCENTRATION DURING MELTING,
Johannessen, M., and Henriksen, A.
Norsk Institute for Vannforskning, Blindern.
Water Resources Research, Vol. 14, No. 4, p 615-619, August, 1978. 7 fig, 4 tab,'
12 ref.
98
-------
Descriptors: *Snow, *Snowmelt, *Melt water, *Water chemistry, Laboratory tests,
On-site investigations, Lysimeters, Snowpacks, Hydrogen ion concentration, Acids.
Over much of Norway a large portion of the yearly precipitation falls as snow,
and the pollutants contained in precipitation accumulate in the snowpack to be
released during a short period in spring. Atmospheric fallout of sulfur com-
pounds has been estimated to be about 30% of the total deposition in Norway, but
fallout on the snow cover is probably considerably smaller. During winters with
little or not snowmelt before spring, most of the pollutant load is retained in
the snowpack. Laboratory and field lysimeter experiments indicated that 5-80%
of the pollutant load is released with the first 30% of the meltwater. The
average concentration of pollutants in this fraction is 2-2.5 times the concen-
tration in the snowpack itself. The very first fractions may contain more than
5 times the snowpack itself. These high concentrations may be due to a freeze-
concentration process during snow recrystallization and melting in which contami-
nants accumulate preferentially at the surfaces of ice particles. The resulting
increase in the acid concentration of low-buffered water courses occassionally
leads to social physiological stress to fish and other aquatic organisms and even
to massive fish kills. This process occurs at a time which is critical to the
hatching stage of salmonid fish species.
78:02K-045
ELECTRON PROBE MICROANALYSIS OF CALCITE GRAINS CONTAINING PHOSPHORUS IN SOIL,
Qureshi, R.H., and Jenkins, D.A.
Agricultural University, Lyallpur, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 703-705, September-
October, 1978. 4 fig, 11 ref.
Descriptors: Calcite, Phosphorus, Chemical analysis. Soil tests, Nutrients,
Soil analysis, Analytical techniques.
Calcite, comprising both clastic sand-sized grains and fossil foraminifera
inherited from a marine Cretaceous (Gault)clay, was isolated from a haplaquept
(gleyic brown calcareous earth) in the United Kingdom and shown by wet chemical
analysis to contain an average of 0.3% phosphorus. Electron probe microanalysis
indicated that this phosphorus is uniformly distributed within the calcite
rather than concentrated as discrete calcium phosphates, and it was concluded
that it was biogenic-diagenic rather than pedogenic in origin. Such sources
were found to constitute 50-80% of the total soil phosphorus and thus suggested
to be relatively available in the upper horizons of the profile.
78:02K-046
THE SPECTROPHOTOMETRIC AND FLUOROMETRIC DETERMINATION OF ALUMINUM WITH 8-
HYDROXYGUINOLINE AND BUTYL ACETATE EXTRACTION,
Bloom, P.R., Weaver, R.M. , and McBride, M.B.
Minnesota University, St. Paul, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 713-716, September-
October, 1978. 2 fig, 3 tab, 11 ref.
(See: 78S07B-018)
78:02K-047
CATION EXCHANGE EQUILIBRIA IN A MIXED SOIL SYSTEM CONTAINING THREE HETEROVALENT
CATIONS ,
Wiedenfeld, R.P., and Hossner, L.R. .
Texas Agricultural Experiment Station, Weslaco, Department of Soil and Crop
.
Soil Science Society of America Journal, Vol. 42, No. 5, p 709-712, September-
October, 1978. 4 fig, 1 tab, 12 ref, 15 equ.
Descriptors: Cation exchange, Cations, Chemical reactions, Thermodynamic
behavior, Equilibrium, Calcium, Magnesium, Sodium.
Cation exchange equations used with soils have been suitable only for systems
containing two cations. Theoretical exchange equilibria relationships for a
mixed soil system containing three heterovalent cations: Ca(2+>, Mg(2+), and
Na(+); were presented. Predictive equations for this tertiary system were derived
i,
99
-------
using solid phase activity coefficients and thermodynamic equilibrium constants
for the three binary systems obtained from experimental data. Theoretical
cation exchange equilibria described for this tertiary system were in agreement
with recognized exchange properties for these three cations. Interactions between
two cations as they affect the exchange behavior of a third cation were also
predicted. The methods presented are applicable to systems containing any
number of heterovalent cations.
78:02K-048
TEMPERATURE AND pH AS LIMITING FACTORS IN LOSS OF NITRATE FROM SATURATED ATLANTIC
COASTAL PLAIN SOILS,
Gilliam, J.W., and Gambrell, R.P.
North Carolina State University, Raleigh, Department of Soil Science.
Journal of Environmental Quality, Vol. 7, No. 4, p 526-532, October-December,
1978. 5 fig, 2 tab, 35 ref.
Descriptors: Nitrates, Reduction (chemical), Denitrification, Nitrogen, Water
pollution, Groundwater, Atlantic Coastal Plain.
Nitrate reduction rates under water-saturated conditions were determined for two
acid Atlantic Coastal 'Plain topsoils and their acid subsoils at 5, 15, and 25 C.
Nitrate reduction readily occurred in subsoils even at pH values of 4.5 when an
energy source was added. It was concluded that the acid pH values which commonly
occur in Atlantic Coastal Plain soils is not a serious limiting factor in NO3(-)
reduction. It was also concluded that the temperatures of 5 to 15 C which exist
in the shallow groundwater of the Atlantic Coastal Plain soils during much of
the winter limits the .rate of N03(-) reduction and nitrate reduction can occur
in these soils at 5 C but the rate is relatively slow and is highly dependent
upon the amount of available C. A significant amount of NO3(-) reduction was
expected during the winter in poorly drained soils which contain relatively high
organic matter contents.
78:02K-049
METABOLISM OF NITROPHENOLS IN FLOODED SOILS,
Sudhakar-Barik, and Sethunathan, N.
Central Rice Research Institute, Cuttack-753006, India, Laboratory of Soil
Microbiology.
Journal of Environmental Quality, Vol. 7, No. 3, p 349-352, July-September, 1978.
4 tab, 12 ref.
Descriptors: Orgdnophosphorus compounds, Flooding, Water pollution, Nitrites,
Isotope studies, Pollutants.
Nitrophenols (p-,0-> and m-isomers and 2,4-dinitrophenol) disappeared fairly rapidly
from flooded alluvial and organic matter-rich acid sulfate (pokkali) soils inoc-
ulated with parathion (0,0-diethyl 0,p-nitrophenyl phosphorothioate)-enrichment
cultures from the respective soils. Nitrite, one of the reported end-products of
nitrophenol (0,0-dimethyl 0,p-nitrophenyl phosphorothioate) metabolism, accumulated
only in inoculated alluvial soil, irrespective of the type of nitrophenol added.
In an isotope study, ring cleavage of p-nitrophenol leading to carbon dioxide
was demonstrated in flooded soils inoculated with parathion-enrichment culture,
particularly under stirred conditions. Nitrophenols decomposed also in uninoculated
samples of both soil types, though slowly as compared to inoculated soils; but
nitrite and carbon dioxide were not formed. Resting cells of a bacterium,'
Pseudomonas sp. ATCC 29353, readily hydrolyzed parathion and then liberated nitrite .
from p-nitrophenol. In cell-free suspension, the reaction ceased at the p-nitropheno1
stage. In bacterial cultures, parathion was hydrolyzed without proliferation while
subsequent degradation of p-nitrophenol involved metabolism leading to bacterial
enrichment.
78:02K-050
CATION-EXCHANGE CAPACITY OF CLAY-RICH SOILS IN RELATION TO ORGANIC MATTER, MINERAL
COMPOSITION, AND SURFACE AREA,
Martel, Y.A., De Kimpe, C.R., and Laverdiere, M.R.
Agriculture Canada, 2560 chemin Gomin, Sainte-Foy, Quebec, GIV 2J3, Canada.
Soil Science Society of America Journal, Vol. 42, No. 5, p 764-767, September-
October, 1978. 1 fig, 7 tab, 16 ref.
100
-------
Descriptors: Cation exchange, Clay minerals, Clays, Organic matter, Minerology,
Soil horizons, Regression analysis, Soil texture.
Regression analyses were used to correlate organic matter, texture and surface
area values to the cation-exchange capacity (CEC) or clay-rich soils in the low-
lands of Quebec. The Ap, Bg and Cg horizons of 11 Gleysolic soils (Agu-Suborders)
were analyzed for CEC, exchangeable bases and acidity, total and fine clay contents,
organic matter, surface area and mineralogical composition. The soils contained
illite, chlorite, smectite, and vermiculite in addition to quartz and feldspars.
In the Ap horizon, total clay and fine clay contents were better related to CEC
than organic matter and surface area. In the Bg and Cg horizons, surface area
gave the best correlation with CEC. As calculated by multiple regression equa-
tions, CEC values of organic matter increased with depth from 56.5 to 223 meq/
100 g, while CEC values of total clay decreased from 37.7 to 22.5 meq/100 g and
that of fine clay decreased from 57.5 to 50.7 meq/100 g. Variations in the
mineralogical composition, although small, were sufficient to explain nearly 50%
of the variations in the CEC.
78:02K-051
ADSORPTION AND EXTRACTABILITY OF MOLYBDENUM IN RELATION TO SOME CHEMICAL PROPERTIES
OF SOIL,
Karimian, N., and Cox,F.R.
Pahlavi University, Shiraz, Iran, College of Agriculture, Department of Soil
Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 757-761, September-
October, 1978. 3 fig, 4 tab, 32 ref.
Descriptors: Molybdenum, Adsorption, Soil chemical properties, Soil tests,
Iron oxides, Organic matter, Hydrogen ion concentration, Phosphorus.
Adsorption of Mo from aqueous solutions was determined for eight soils from the
Atlantic Coastal Plain and Piedmont regions. The data followed the Freundlich
isotherm more consistently than the Langmuir. Adsorption increased as the organic
matter and/or Fe oxide contents of the soils increased. Adsorption from an
aqueous solution that was initially 0.3 mM Mo (AdMo) also was determined on 32
soils collected from the regions. The AdMo level was positively correlated with
Fe oxide and organic matter contents and negatively correlated with pH and P
levels. The level of Mo extracted with acid ammonium oxalate (Grigg Mo) and an
anion exchange resin (resin Mo) were also determined and related to soil chemical
properties and a lime treatment. Grigg Mo was positively correlated with amor-
phous and free Fe oxide by oxalate. Resin Mo was positively correlated with pH
but not with other soil properties. Incubating soils with CaC03 increased the
level of resin Mo.
78:02K-052
CHEMICAL CHARACTERIZATION OF THE GASEOUS AND LIQUID ENVIRONMENTS OF SUBSURFACE
DRAIN SYSTEMS,
Meek, B.D., Grass, L.B., and MacKenzie, A.J.
Imperial Valley Conservation Research Center, Brawley, California.
Soil Science Society of America Journal, Vol. 42, No. 5, p 693-698, September-
October, 1978. 3 fig, 6 tab, 14 ref.
Descriptors: Chemical precipitation, Subsurface drains, Subsurface drainage,
Aeration, Iron, Manganese, Oxygen, Drainage water, Oxidation, Reduction (chemical).
Chemical composition of subsurface drain effluents was determined in the field as
a function of location (various depths and soil textures), entry point of the
solution into the drainpipe, and distance from outlet (with or without a water
trap). Liquid samples were analyzed for Fe, Mn, NO3-N, HC03, organic carbon,
electrical conductivity, pH, and dissolved oxygen, and gas samples were analyzed
for 02 and C02.
78:02K-053
BIOLOGICAL HYDROLYSIS OF PARATHION IN NATURAL ECOSYSTEMS,
Sudhakar-Barik, and Sethunathan, N.
Central Rice Research Institute, Cuttack-753006, India, Laboratory of Soil
Microbiology.
101
-------
Journal of Environmental Quality, Vol. 7, No. 3, p 346-348, July-September,
1978. 5 tab, 11 ref.
Descriptors: Organophosphorus compounds. Flooding, Hydrolysis, Water pollution.
Parathion (0,0-diethyl 0,p-nitrophenyl phosphorothioate) was applied to flooded
soils and to water and sediment river, lake, and pond samples at 15-day intervals.
While p-nitrophenol (0,0-dimethyl 0,p-nitrophenyl phosphorothioate), the hydrolysis
product of parathion, was not detected, even at the end of 12 days after the first
addition, it was detected in all samples within 6 hours after two or three additions
of the insecticide. Enrichment cultures from the samples of different ecosystems
lost their ability to hydrolyze parathion following autoclaving, suggesting micro-
bial participation in parathion hydrolysis.
78:02K-054
EXTRACTABILITY OF CADMIUM, COPPER, NICKEL, AND ZINC BY DOUBLE ACID VERSUS DTPA
AND PLANT CONTENT AT EXCESSIVE SOIL LEVELS,
Korcak, R.F., and Fanning, D.S.
United States Department of Agriculture, Science and Education Administration,
Fruit Laboratory, Beltsville Agricultural Research Center-West, Beltsville,
Maryland.
Journal of Environmental Quality, Vol. 7, No. 4, p 506-512, October-December, 1978.
1 fig, 9 tab, 18 ref.
(See 78:021-032)
78:02K-055
INFLUENCE OF THE CHEMICAL FORM OF MERCURY ON ITS ADSORPTION AND ABILITY TO LEACH
THROUGH SOILS,
Hogg, T.J., Stewart, J.W.B., and Bettany, J.R.
Saskatchewan University, Saskatoon, Saskatchewan, Canada, Institute of Pedology.
Journal of Environmental Quality, Vol. 7, No. 3, p 440-445, July-September, 1978.
2 fig, 4 tab, 19 ref.
Descriptors: Mercury, Adsorption, Leaching, Volatility, Sewage effluents, Sewage
disposal, Irrigation, Soil analysis.
The adsorption of Hg by two soils, differing in chemical and physical characteristic3'
indicated that both methyl mercuric chloride {MMC) and phnyl mercuric acetate (PMA)
and mercuric chloride (HgC12) followed the linear form of the Langmuir adsorption
isotherm. The highest adsorption maxima for all Hg compounds were found for the
soils which had the higher organic matter content and clay content. Adsorption
maxima increased in the order MMC < PMA < HgC12. A two-rate effluent leaching
experiment was conducted utilizing undisturbed soil cores of the same two soils and
the same three Hg compounds (labeled with 203Hg) which were applied uniformly to
the top 0-10 cm >f each column. In contrast to the movement of other cations in
the effluent and soil, even at the higher irrigation rate, none of the applied Hg
was found to move below the 10- to 20-cm soil layer. The lack of movement of
Hg and the high adsorption maxima was a consequence of the strong, binding between
Hg compounds and soil. The inability of weak chemical extractants (CaC12, NH40AC,
DTPA, EDTA) to remove significant quantities of Hg confirmed this hypothesis.
Seven to 31% of the applied Hg was lost from the columns during the experiment
presumably by volatilization.
78:02K-056
SEASONAL VARIATION IN PC02 AND 13C CONTENT OF SOIL ATMOSPHERE,
Rightmire, C.T.
United States Geologic Survey, Idaho National Engineering Laboratory, Idaho Falls.
Water Resources Research, Vol. 14, No. 4, p 691-692, August, 1978. 1 fig, 9 ref,
2 equ.
Descriptors: Soil gases, Soil environment, Carbon dioxide, Seasonal, Groundwater
recharge, Artificial recharge.
Soil carbon dioxide is the dominant source of dissolved inorganic carbon in
recharging waters. Samples of soil C02 were collected to determine if seasonal .
variations in 13C content parallel those previously observed for PCO2. Signifi-
cant seasonal variations in both PC02 and 13C content were observed. The data
102
-------
presented in this paper indicated that the studies of groundwater carbonate
chemistry require knowledge of the season during which major recharge occurs.
78:02K-057
LONG-TERM DENITRIFICATION STUDIES IN SOILS FERTILIZED WITH (15NH4)2S04(1),
Focht, D.D., and Stolzy, L.H.
California University, Riverside, Department of Soil and Environmental Sciences.
Soil Science Society of America Journal, Vol. 42, No. 6, p 894-898, November-
December, 1978. 6 fig, 1 tab, 31 ref, 3 egu.
Descriptors: Denitrification, Nitrogen, Nitrates, Nitrogen cycle, Soil gases,
Air pollution, Lysimeters, Isotope studies, Fertilization.
A 2-year study was conducted in lysimeters containing four different soils with
successive summer and winter crops of corn and barley, respectively. The crops
were fertilized with (15NH4)2SO4 at application rates equivalent to 134, 108,
415, and 440 Kg N/ha for the respective summer 1973, winter 1974, summer 1974, and
winter 1975 crops. The frequency of 15N dinitrogen samples was higher in the
summer and high at the lower fertilizer rates, while the reverse was true for
NO3(-J concentrations in leach water and N20 concentrations in the soil profile.
Emissions of N20 from soil, even where the higher concentrations were observed,
were low in terms of N losses with the greatest mass emission at any time
amounting to 6.5 g/ha over a 1-day period. Nitrogen gas emissions over a 1-week
period in one instance were estimated at 5.2 kg N/ha: it was observed that this
amount could be generated from low (1 ppm or less) concentrations of N20.
78:02K-058
EXCHANGE ADSORPTION OF TRACE QUANTITIES OF CADMIUM IN SOILS TREATED WITH CALCIUM
AND SODIUM: A REAPPRAISAL,
Milberg, R.P., Brower, D.L., and Lagerwerff, J.V.
Agricultural Environmental Quality Institute, Beltsville Agricultural Research
Center, Beltsville, Maryland 20705.
Soil Science Society of America Journal, Vol. 42, No. 6, p 892-894, November-
December, 1978. 2 tab, 4 ref, 1 equ.
Descriptors: Cation exchange, Cation adsorption, Cadmium, Calcium, Sodium,
Organic matter.
This paper presents a reevaluation and revision of the data on Ca-Cd and Na-Cd
exchange in three soils originally presented in an earlier paper (Lagerwerff
and Brower, Soil Sci. Am. Proc. 36:734-737). Cadmium was selectively adsorbed
over Ca in Cecil, Winsum, and Yolo soils with up to 1.7% of the total cation
exchange capacity occupied by Cd. Selectivity was greatest in Yolo and least
in Cecil. Effects of undissociated Cd in solution were minor. Separation
factors decreased with increasing exchangeable Cd. Reexamination of Cd-Na
exchange revealed that anomalous earlier results were due to the dispersion
of organic matter during treatment with Na2CO3 in the preparation of Na-saturated
soils. Na-Cd exchange was normal where organic matter loss was prevented.
78:02K-059
SERIOUS INTERFERENCES IN THE DETERMINATION OF TRACE METALS IN SOILS BY FLAME
AND FLAMELESS ATOMIC ABSORPTION SPECTROMETRY,
Mubarak, A., Hageman, L., Howald, R.A., and Woodriff, R.
Montana College of Mineral Science and Technology, Butte, Department of
Chemistry.
Soil Science Society of America Journal, Vol. 42, No. 6, p 889-891, November-
December, 1978. 5 tab, 14 ref.
Descriptors: Trace elements, Spectrometers, Chemical analysis. Soil chemistry;
Absorption.
Negative interfering effects on the carbon rod atomizer (CRA) absorbances of Mn,
Fe, and Ni were found to occur in the presence of the chlorides of the major
cations (Ca, Mg, Na) in the soil solution. These interferences were corrected
either by precipitation of the chlorides with silver nitrate or by incorporating
a relatively high level of sulfuric or nitric acid into the sample volume.
103
-------
Magnesium ion, irrespective of the associated anion, was found to lower the Cd
signal on the CRA. High concentrations of MgSO4 caused lowering of the Mn
signal when using air-acetylene 'flame. This lowering effect of MgS04 was
avoided upon using N2O-acetylene flame. No interferences were noticed for Mn and
Zn when using the constant temperature furnace developed at Montana State
University.
78:02K-060
SURFACE CHARGE MANIPULATION IN CONSTANT SURFACE POTENTIAL SOIL COLLOIDS: II.
EFFECT ON SOLUTE TRANSPORT,
Wann, S.S., and Uehara, G.
Hawaii University, Honolulu, Department of Agronomy and Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 6, p 886-888, November-
December, 1978. 6 fig, 2 tab, 6 ref, 1 equ.
Descriptors: Ion transport, Ion exchange. Colloids, Nutrient removal, Potassium,
Phosphorus, Isotherms.
Potassium breakthrough curves from soil columns containing samples collected from
an oxic horizon of a Typic Torrox shifted to the right as the sample was treated
with increasing levels of P. The shift in the breakthrough curve was significantly
related to a lowering of the zero point of charge. The lowering of the zero
point of charge was in turn related to levels of applied P. The anion accompanying
K also had a marked effect on the position of the breakthrough curve. When
the accompanying anion was Cl, S, and P respectively, the K concentration in the
effluent attained one-half of influent concentration at 4.25, 5.30, and 8.20 pore
volumes.
78:02K-061
FIELD MEASUREMENT OF DENITRIFICATION: I. FLUX OF N2 AND N2O,
Rolston, D.E., Hoffman, D.L., and Toy, D.H.
California University, Davis, Department of Land, Air and Water Resources.
Soil Science Society of America Journal, Vol. 42, No. 6, p 863-869, November-
December, 1978. 7 fig, 3 tab, 16 ref, 3 equ.
Descriptors: Denitrification, Nitrogen, Nitrogen cycle, Measurement, Soil gases,
Diffusion, Soil moisture, Soil temperature. Water pollution.
•
The objective of the research reported in this paper was to measure denitrificatibn
in a field soil directly from the fluxes of N2 and N2O at the soil surface at a
high and low soil temperature, at two water contents near saturation, and at three
levels of C input (cropped, uncropped, and manure). The research was conducted
on small one-m2 field plots because of the large cost of N03(-) fertilizer tagged
with high enrichments of 15N.
78:02K-062
DETERMINATION OF THE APPARENT DISPERSION COEFFICIENT OF.SOLUTES IN UNSATURATED
SOIL,
Paetzold, R.F., and Scott, H.D.
United States Department of Agriculture, Soil Conservation Service, National Soil
Survey Laboratory, Lincoln, Nebraska 68508.
Soil Science Society of America Journal, Vol. 42, No. 6, p 874-877, November-
December, 1978. 3 fig, 1 tab, 14 ref, 16 equ.
Descriptors: Dispersion, Solutes, Diffusion, Convection, Unsaturated flow,
Radioisotopes, Pesticides, Herbicides, Soil chemistry.
A method for determining the apparent dispersion coefficient of a solute in
unsaturated soils at relatively low soil water flow rates was presented. Two
soil cores with different initial water contents were joined and water allowed to
flow between the soil cores for a specified time interval. The distribution of
a radioactively tagged solute, initially present in one of the soil cores, was
subsequently determined by freezing the cores in liquid air, sectioning the soil •
with a refrigerated microtome, and analyzing the soil sections for solute content
using liquid scintillation techniques. Apparent dispersion coefficients could-be
determined either with or against the water, flow. The solutes used in this study
were tritiated water, chloride, and metribuzin (a herbicide).
104
-------
78:02K-063
A UNIVERSAL DIMENSIONLESS PHOSPHATE ADSORPTION ISOTHERM FOR SOIL,
Shayan, A., and Davey, B.C.
Arya-Mehr University of Technology, Isfahan, Iran.
Soil Science Society of America Journal, Vol. 42, No. 6, p 878-882, November-
December, 1978. 3 fig, 1 tab, 20 ref, 5 equ.
Descriptors: Adsorption, Phosphates, Isotherms, Kaolinite, Chemical potential,
Fertilizers, Soil chemistry.
A unique dimensionless phosphate adsorption isotherm, covering the solution
concentration range 0.000001 to 0.1M P, which has been found to fit 17 materials
including 15 soils, pure kaolinite and amorphous Al(OH)3, was derived. The soils
shown to fit the isotherm included chronic luvisols, pellic vertisols, calcic
luvisols, a tropeptic eutrorthox, a volcanic ash soil from New Zealand, and a
number of English soils. The necessary parameters to derive a complete adsorp-
tion isotherm for a particular soil from the universal isotherm, required three
adsorption experiments in the high concentration range (0.000001 to 0.0001H P)
to define the linear portion of the isotherm and the critical concentration.
Three other determinations in the range 0.000001 to 0.0001N P were needed to ob-
tain the areundlich isotherm from the data after correction, for the effect of the
linear region of the isotherm at high concentration. The advantage of this
universal isotherm over conventional isotherms, is that it requires less experi-
mental work to define and is applicable over a wide range of P concentrations
such as might be found surrounding a fertilizer granule.
78:02K-064
CHLORIDE AS A FACTOR IN MOBILITIES OF Ni{II), Cu(II), AND Cd(II) IN SOIL,
Doner, H.E.
California University, Berkeley, Department of Soils and Plant Nutrition.
Soil Science Society of America Journal, Vol. 42, No. 6, p 882-885, November-
December, 1978. 5 fig, 3 tab, 15 ref, 4 equ.
Descriptors: Trace elements/ Metals, Chlorides, Adsorption, Ion transport,
Leachate, Chemical analysis, Soil analysis, Water pollution. Laboratory tests.
An investigation was undertaken to study the mobility of chloro-complexes of
Ni(ii), Cu(II), and Cd(II) through soil. Soil columns were leached with 0.1,
0.2, 0.3, or 0.5M NaCl or CaC104 solutions, each containing 10 microgram/ml
Ni(ii), Cu(II), or Cd(II). Sodium perchlorate solutions were used as a compari-
son with CaCl at the same ionic strength since perchlorate is not considered to
form complexes with the metals. Leachates from columns and soils were collected
and analyzed. Mobility of all metals tested in chloride solutions was from 1.1
to 4 times greater than that in C104(-) solution. Chloride increased the
mobility of Cd(II) the most which corresponds to its having the largest stability
constants. Copper (II) was slowest to appear in the leachate and was strongest
adsorbed as evidenced by analysis of soil by digestion with either 4N HN03 or
acidified NH20H-HC1. These results showed that Cl(-) has a marked effect on the
mobility of Cd(II) and, to a lesser extent, Ni(II) and Cu(II).
78:02K-065
A KINETIC STUDY OF THE CaCO3 PRECIPITATION REACTION,
Gilmour, J.T., Shirk, K.S., Ferguson, J.A., and Griffis, C.L.
Arkansas University, Fayetteville, Department of Agronomy.
Agricultural Hater Management, Vol. 1, No. 3, p 253-262, November, 1978. 2 fig,
4 tab, 10 ref, 5 equ.
Descriptors: Chemical precipitation, Chemical reactions. Soil chemistry,
Calcium carbonate, Magnesium carbonate. Kinetics, Water management (applied),
Mathematical models, Rice.
In order to develop water management practices which would minimize localized
precipitation of Ca and Mg carbonates on Arkansas' rice fields, a description
of the precipitation reaction was needed. Waters studied were prepared solutions
which contained varying amounts of Ca(HCO3)2, Mg
-------
order kinetics where Ca was the rate determining ion. An empirical equation
was developed which showed that the rate constant could be calculated from
temperature and solution composition data. An evaluation of the rates of Ca and
Mg loss from solution for the experimental periods studied showed that Mg losses
were small when compared to Ca losses.
78:02K-066
THE NITROGEN-15 ABUNDANCE IN A WIDE VARIETY OP SOILS,
Shearer, G., Kohl, D.H., and Chien, S-H.
Washington University, St. Louis, Missouri, Center for the Biology of Natural
Systems.
Soil Science Society of America Journal, Vol. 42, No. 6, p 899-902, November-
December, 1978. 1 fig, 6 tab, 13 ref, 2 equ.
Descriptors: Nitrogen, Soil chemical properties, Fertilizers, Environment,
Soil chemistry, Sampling, Correlation analysis.
One hundred thirty-nine soil samples from 20 states were analyzed for 15N
abundance. Soil characteristics and environmental conditions at the sampling
sites varied widely. The total N of surface soil samples had a mean delta 15N
value (per mill 15N excess) slightly but significantly higher than the mean
value for soils collected from deeper layers, although the relationship between
delta 15N and soil depth was not consistent from location to location. Differences
among mean delta 15N values for the total N of soil samples collected from crop-
land, pasture, uncultivated land (with native herbs), and forest were not
striking. There was no systematic effect of variation in the rate of application
of N fertilizer on the delta 15N of the total N of soils. The mean delta 15N
value of surface soils, with respect to atmospheric N, was +9.22 and the
standard deviation was 2.10 delta 15N units. The range within which 90% of the
samples fell was +5.1 to +12.3 delta 15N units. Less than half of the variation
among the soils in delta 15N of the total N could be accounted for by differences
in environmental variables or soil characteristics.
78:02K-067
NITROGEN MINERALIZATION AND DENITRIFICATION IN ORGANIC SOILS,
Guthrie, T.F., and Duxbury, J.M.
Cornell University, Ithaca, New York, Department of Soil Organic Chemistry.
Soil Science Society of America Journal, Vol. 42, No. 6, p 908-912, November-
December, 1978. 1 fig, 6 tab, 13 ref.
Descriptors: Nitrogen, Denitrification, Organic soils. Nitrates, Leachate,
Laboratory tests.
The quantities of N mineralized when columns of Histosols were incubated at field
capacity for period up to 28 days corresponded to 500-600 kg N/ha per year without
correction for N lost by denitrification. An absorption train utilizing molecular
sieve 5A to collect N2O was used in denitrification experiments. Under an argon
stream, 52-53% of the added NO3(-)-N was recovered as N2O, whereas the maximum
concentration of N20 accumulating in the headspace of closed vessels amounted to
65% of the added N03(-)-N. The quantity of N2O either collected or accumulating
in a headspace was reduced to 15-41% of the N03(-)-N denitrified when a second
addition of N03(-) was made to the soils. Denitrification occurred in both drained
and flooded soil columns amended with N03(-). The N20 recovered ranged from 2.5-
9% and 9-19% of the N03(-)-N denitrified in the drained and flooded columns,
respectively.' From 78-98% of the N2O was recovered in leachate from the flooded
columns and the corresponding range for the drained columns was 11-52%.
78:02K-068
NITRATE REDUCTION TO AMMONIUM IN ANAEROBIC SOIL,
Buresh, R.J., and Patrick, W.H.
Louisiana State University, Baton Rouge, Center for Wetland Resources.
Soil Science Society of America Journal, Vol. 42, No. 6,-p 913-918, November-
December, 1978. 3 fig, 3 tab, 32 ref.
Descriptors: Nitrates, Reduction (chemical), Anaerobic conditions, Denitrifica-
tion, Nitrogen, Oxidation-reduction potential. Soil chemistry.
106
-------
The objectives of this study were: (i) to compare the influence of various C
substrates upon the extent of NO3(-) reduction to NH4(+) relative to denitrifi-
cation in anaerobic soil, and (ii) to determine the significance of NO3(-)
conversion to NH4(+) and organic N in unamended anaerobic soil. Ammonium
accumulates by way of mineralization under anaerobic conditions, consequently
15N-labelled N03(-) was employed to distinguish between soil and NO3{-) -derived
NH4(+). It was concluded that transformation of significant amounts of N03(-)
to NH4(+) and organic N required intensely reduced soil conditions. The reaction
was apparently not suppressed by NH4(+). Evidence indicated that NO3(-) was
reduced to NH4(+) by a nonassimilatory pathway in which NO3(-) functioned as a
terminal electron acceptor.
78:02K-069
PHOSPHORUS SUPPLYING CAPACITIES OP PREVIOUSLY HEAVILY FERTILIZED SOILS,
Novais, R., and Kamprath, E.J.
Universidade Federal de Vicosa, Brazil, Department of Soils.
Soil Science Society of America Journal, Vol. 42, No. 6, p 931-935, November-
December, 1978. 3 fig, 7 tab, 22 ref.
Descriptors: Phosphorus, Soil tests, Soil chemical properties, Fertilizers,
Nutrient removal, Chemical analysis, Soil analysis, North Carolina.
Four Coastal Plain soils and one Piedmont soil heavily fertilized in the past were
intensively cropped in greenhouse pots to determine changes in extractable soil
P as measured by North Carolina, Bray I and Olsen extractants. Slopes relating
changes in extractable P with P removed by cropping were very similar for the
three sandy soils. Changes in extractable P with the North Carolina and Bray
I extractants were correlated with P buffer capacity, % clay, and soil surface
area. The principal source of P removed by cropping was NH4F-P in sandy Coastal
Plain soils; NH4F-P and NaOH-P supplied equal amounts in the clayey Piedmont
soil. Sandy Coastal Plain soils which originally contained more than 74 ppm
North Carolina extractable P and 71 ppm Bray I extractable P supplied 82 to 108
kg P/ha to nine crops of pearl millet (Pennisetum americanum, cv. Gahi-1).
78:02K-070
CATION EXCHANGE EQUILIBRIA IN FLORIDA AND INDIANA HISTOSOLS,
Baligar, V.C., Barber, S.A., and Myhre, D.L.
Purdue University, West Lafayette, Indiana.
Soil Science, Vol. 126, No. 2, p 109-117, August, 1978. 2 fig, 4 tab, 31 ref,
8 egu.
Descriptors: Cation exchange, Organic soils, Cation adsorption, Selectivity,
Potassium, Isotherms, Soil chemistry, Soil chemical properties, Florida, Indiana,
Ion exchange equilibria have been investigated in mineral soils, but little infor-
mation is available for organic soils. This investigation was undertaken to
characterize the cation selectivity' of differing histosols and to determine a
suitable cation exchange equation to express the ion selectivity in these soils.
Four histosols were incubated for 3 weeks with 5 levels of K and Rb. At the end
of incubation, ions in soil solution and on the adsorbed phase were determined.
All soils had a greater fraction of Ca in the exchange phase than in solution,
whereas with Mg, Mn, K, and Rb, the reverse occurred. Increasing K and Rb satura-
tion was related to an increase in selectivity coefficient for Rb-K. On the
Pahokee muck soils, Rb was adsorbed more tightly than K, where the amount of Rb
added exceeded 1.0 me/100 g of soil. On the Edwards muck soil, Rb was adsorbed
preferentially to K at all levels. Magnesium was adsorbed preferentially to Ca
on the Edwards muck soil, but not on the Pahokee soils. Selectivity coefficients
for K-Ca were calculated using the Kerr, Gapon, Krishnamoorthy and Overstreet,
Vanselow, and Scheffer and Ulrich equations. In all but the Scheffer and ulrich
equation, the selectivity coefficient decreased as K and Rb were increased. In
the latter it increased. No equation satisfactorily described the system.
107
-------
78:02K-071
NITROGEN AND CHLORIDE LEACHING IN A SANDY FIELD PLOT,
Cameron, D.R., Kowalenko, C.G., and Ivarson, K.C.
Soil Research Institute, Agriculture Canada, Ottawa, Ontario K1A OC6.
Soil Science, Vol. 126, No. 3, p 174-180, September, 1978. 3 fig, 2 tab, 15 ref.
Descriptors: Nitrogen, Chloride, Leaching, Leachate, Environmental sanitation,
Denitrification, Nitrates.
In field experiments conducted on a well-drained, sandy soil, 59 and 99 percent
of the added chloride was lost by leaching from the 0-75-cm layer by the end
of October in 1975 and 1976, respectively. Chloride losses were proportional to
total precipitation. The average spring-to-fall rates of N losses for 1975 and
1976 were 0.65 and 1.45 kg N/ha/day, and were directly proportional to N
fertilization rates of 120 and 255 kg/ha, respectively. N03-N and Cl tended to
show similar distribution patterns in the profile, and ratios of Cl to N03-N in-
dicated predominant leaching rather than denitrification losses. N and Cl losses
appeared to be associated with irregular, diffuse bulges, rather than with distinct
peaks of solute moving steadily downward.
78:02K-072
INFLUENCE OF PHOSPHORUS ON ZINC, IRON, MANGANESE, AND COPPER UPTAKE BY PLANTS,
Wallace, A., Mueller, R.T., and Alexander, G.V.
California University, Los Angeles, Laboratory of Nuclear Medicine and Radiation
Biology.
Soil Science, Vol. 126, No. 6, p 336-341, December, 1978. 3 tab, 28 ref.
Descriptors: Nutrient removal, Nutrients, Zinc, Iron, Manganese, Copper,
Phosphorus, Plant growth, Beans.
Five cultivars of soybeans (Glycine max. L.) and a bush bean (Phaseolus vulgaris
L. cv "Improved Tendergreen") were grown in nutrient solutions with different
P levels, solution pH, and, in the case of bush bean, at different Fe levels.
The objective of the experiments was to obtain more definitive answers to problems
of P-induced Zn and Fe deficiencies. Differential solution pH, obtained by
adding solid phase CaCO3 to the nutrient solution (about pH 7) vs. a regular
solution (about pH 4-5), indicates that pH is very important in the effects ob-
tained. At high pH, increasing solution P decreased the leaf, stem, and root
concentrations of Zn, Mn, and Cu in soybeans. Iron was decreased in roots, but
not in leaves and stems. In contrast, at low pH, increasing the P resulted in
more Zn, Mn, and Cu but less Fe in leaves, stems, and roots. Results with bush
beans were only slightly different from those with soybeans, and the Zn-P effects
were modified slightly by Fe levels. High P decreased Fe transport to leaves in
bush beans at low and high pH, but only at the high Fe level.
78:02K-073
EFFECT OF SULFATE IONS ON THE STABILITY AND EXCHANGE CHARACTERISTICS OF AN
ALUMINUM-INTERLAYERED WYOMING BENTONITE,
Singh, S.S., and Miles, N.M.
Soil Research Institute, Research Branch, Agriculture Canada, Ottawa, Ontario
K1A 06C, Canada.
Soil Science, Vol. 126, No. 6, p 323-329, December, 1978. 2 fig, 4 tab, 16 ref.
Descriptors: Bentonite, Suspension, Clay minerals, Sulfates, Chemical precipi-
tation, X-ray diffraction, Chemical properties, Soil chemistry.
Alurainura-interlayered, Wyoming bentonite suspensions, containing different
amounts of precipitated Al, were equilibrated with S04 solutions at different
concentrations. The amount of Al precipitated as Al-hydroxy complex was 400,
550, and 750 me/100 g clay, and the concentration of SO4 in solution as 10, 20,
and 30 me/1. On equilibration, the hydroxy-Al interlayer precipitate in the
Wyoming bentonite reacted with S04 ions, and a neutral precipitate of aluminum
hydroxy sulfate was formed. Heating the Wyoming bentonite to 700°C resulted in
complete collapse, showing that the precipitate was no longer present in the
interlayer space. A crystalline compound of aluminum liydroxy sulfate was formed
as evidenced by x-ray diffraction patterns. In the case of Al-interlayered,
Wyoming bentonite suspensions that were not equilibrated with SO4 solution, the
Al-hydroxy precipitate remained in the interlayer space and blocked the exchange
sites. Treatment of these samples with S04 solutions resulted in an increase of
exchange capacity that was concentration-dependent.
108
-------
78:02K-074
EVALUATION OF AMMONIUM RELEASE BY ALKALINE PERMANGANATE EXTRACTION AS AN INDEX
OF SOIL NITROGEN AVAILABILITY,
Stanford, G.
United States Department of Agriculture, Science and Education Administration,
Northeastern Region, Biological and Waste Management and Soil Nitrogen Laboratory,
Beltsville, Maryland 20705.
Soil Science, Vol. 126, No. 4, p 244-253, October, 1978. 1 fig, 4 tab, 27 ref.
Descriptors: Nitrogen, Chemical analysis, Soil chemistry, Organic matter.
Laboratory tests, Hydrolysis, Oxidation.
The relation of potentially mineralizable soil nitrogen, NO, to hydrolytic and
oxidative release of NH4-N from soil organic matter by extraction with alkaline
permanganate was investigated using 62 soils representing several major agricultural
regions in the United States. The NH4-N was recovered by steam-distilling 1-g
samples of soil during extraction for 4 min with several concentrations of NaOH
and KMn04 in different combinations. The same concentrations of NaOH, without
KMn04, were used to determine amounts of NH4-N released by hydrolysis (B) during
steam distillation. Oxidative release was estimated as the difference between
total NH4-N produced during alkaline permanganate extraction (BOx) and that
derived by NaOH distillation. With few exceptions, correlations of NO with BOx
were as good as, or better than, simple correlations of NO with B or (BOx - B).
Thus, the extra effort required for separate NaOH and NaOH-KMn04 extractions did
not appear to be justified. It was concluded that the alkaline permanganate
methods thus far reported by various investigators, as well as modifications
evaluated in this study, offer a less precise and reliable basis for predicting
NO than does acid permanganate extraction for measuring oxidative release of
NH4-N.
78:02K-075
OXIDATIVE RELEASE OF POTENTIALLY MINERALIZABLE SOIL NITROGEN BY ACID PERMANAGANATE
EXTRACTION,
Stanford, G., and Smith, S.J.
United States Department of Agriculture, Agricultural Research Service, Biological
Waste Management and Soil Nitrogen Laboratory, Beltsville, Maryland 20705.
Soil Science, Vol. 126, No. 4, p 210-218, October, 1978. 6 fig, 2 tab, 13 ref.
Descriptors: Nitrogen, Chemical analysis, Soil tests, Organic matter, Soil
chemistry. Laboratory tests, Oxidation.
The relation of potentially mineralizable soil nitrogen, NO, to the oxidative release
of NH4-N from soil organic matter during extraction with acid KMn04 was investigated,
using 62 soils. Included in the study were members of 8 soil orders comprising
43 noncalcareous and 19 calcareous soils. Soils were extracted with 1 N H2S04 solu-
tions of 0.05 and 0.1N KMn04 (HOx) and with 1 N H2S04 (H) alone for 1 h at room
temperature, and amounts of NH4-N released were determined. The expression HOx -
H denotes the quantity of NH4-N released owning to partial oxidation of soil organic
matter. Later, a more direct and simpler procedure for determining oxidative
NH4-N release was adopted, in which soils were preextracted with 1 N acid, and the
soil residues were extracted with acidic KMn04. Regression equations that may be
useful in predicting NO from the oxidative release of NH4-N were developed. Amounts
of NH4-N released by oxidation with 1 N H2SO4 solutions of 0.05 and 1.0 N KMn04,
respectively, were approximately one-third and one-half of NO. It was concluded
that the NH4-N was derived from oxidation of the soil organic N fraction most readily
susceptible to biological mineralization.
109
-------
SECTION XII
WATER SUPPLY AUGMENTATION AND CONSERVATION
WATER YIELD IMPROVEMENT (GROUP 03B)
78:03B-001
ANALYSIS OF FALLOW-FARMING SYSTEMS IN SEMI-ARID AFRICA USING A MODEL TO SIMULATE
THE HYDROLOGIC BUDGET,
Hall, A.E., and Dancette, C.
California University, Riverside, Department of Plant Sciences.
Agronomy Journal, Vol. 70, No. 5, p 816-823, September-October, 1978. 10 fig,
4 tab, 16 ref, 7 equ.
Descriptors: Semiarid climates. Fallowing, Model studies, Simulation analysis,
Hydrologic budget, Evaporation, Water conservation, Soil moisture, Root system.
A model was developed to predict bare soil evaporation, crop water use, and the
distribution of water in the soil. Comparisons with hydrologic budget data ob-
tained in the field with bare soil, cowpeas (Vigna unguiculata (L.) Walp.), and
millet (Pennisetum typhoides (Burm. f.) S. and W.) indicated that the models
performed adequately for the conditions and objectives of the study. Simulations
of annual fallow, predicted that the amounts of water conserved in the soil would
rapidly decrease with decreases in annual rainfall. The simulations predicted
that substantial quantities of water may be conserved in the soil by partial
fallow during wetter years. More soil moisture would be conserved with the
shorter cycle variety, but the longer cycle variety would have greater need for
this moisture in this climatic zone during dry years, indicating a possible
advantage of rotations involving short cycle, and long cycle crops. The simula-
tions predicted that present varieties may only use a small proportion of the
moisture that may be stored below 150 cm depth in the soil by partial fallow,
indicating a possible need for developing varieties with faster growing, deeper,
root systems.
110
-------
SECTION XIII
WATER SUPPLY AUGMENTATION AND CONSERVATION
USE OF WATER OF IMPAIRED QUALITY (GROUP 03C)
78:03C-001
TESTING SALT TOLERANCE VARIABILITY AMONG TALL WHEATGRASS LINES,
Shannon, M.C.
United States Salinity Laboratory, United States Department of Agriculture,
4500 Glenwood Drive, Riverside, California 92501.
Agronomy Journal, Vol. 70, No. 5, p 719-722, September-October, 1978. 1 fig,
3 tab, 22 ref.
Descriptors: Wheatgrass, Salt tolerance, Varieties, Variability, Plant
breeding, Plant physiology.
In the present study a screening procedure was evaluated to determine its
usefulness in detecting variation among introductions of tall wheatgrass (Agro-
pyron elongatum (Host) Beauv.). In greenhouse sand flats, 32 lines of tall
wheatgrass were established and subjected to stepwise increases in salinity up
to 765 meq/liter or until severe leaf damage resulted. The lines were classified
into five groups based on relative leaf damage and recovery rates from salt
treatment. Repeating the screening procedure on seven each of the most tolerant
and most sensitive lines reaffirmed the results of the first screening. Mineral
analyses indicated that tolerance was associated with restricted accumulation
of Na, Ca, and Cl in the shoots. Proline and soluble sugars contributed to
osmotic adjustment at high salinities, but sensitive and tolerant lines did not
differ in proline content. This screening technique appeared to discriminate
between lines with different ion transport properties and different salt
tolerances. The sensitive and tolerant lines identified may be beneficial in
future breeding and physiological studies.
78:03C-002
ROOT GROWTH ALONG PLEXIGLAS SURFACES BY SUGARCANE UNDER DIFFERENT SOIL SALINITY
CONDITIONS,
Gerard, C.J.
Texas ASM University, Vernon, Texas Agricultural Experiment Station.
Agronomy Journal, Vol. 70, No. 4, p 639-643, July-August, 1978. 7 fig, 1 tab,
12 ref.
Descriptors: Root development, Salinity, Moisture stress, Growth stages, Sugar-
cane, Plant growth, Saline soils, Crop response, Saline water.
Root growth of sugarcane (Saccharum officinarum L.) in soils irrigated with
waters with electrical conductivities of 1.1, 5.0, and 8.0 mmhos/cm varied with
stage of plant growth, time and salinity treatments. Root growth was greatest
at soil depths of 20 to 60 cm in May, June, and July, a period of high growth
rate and high evaporative conditions. During these months, average root inten-
sities of sugarcane, irrigated with waters with salinities of 1.1, 5.0, and 8.0
mmhos/cm, were about 0.5, 1.0, and 1.5 mm/sq cm, respectively. Moisture stress
induced by osmotic potentials of about -1.8 and -2.9 bar and high evaporative
conditions stimulated root intensities but reduced top growth by 22 and 50%,
respectively. These studies using root chambers have contributed to a better
understanding of the interactive influences of stages of plant growth, salinity,
and environment on root growth by sugarcane.
78:03C-003
THE EFFECT OF SALT PRECIPITATION AND HIGH SODIUM CONCENTRATIONS ON SOIL HYDRAULIC
CONDUCTIVITY AND WATER RETENTION,
Frenkel, H., Hadas, A., and Jury, W.A.
California University, Riverside, Department of Soil and Environmental Sciences.
Water Resources Research, Vol. 14, No. 2, p 217-222, April, 1978. 5 fig, 4 tab,
21 ref, 8 equ.
Ill
-------
Descriptors: Saline water, Water quality, Salinity, Irrigation, Leaching, Crop
response, Pollution abatement, Chemical precipitation, Hydraulic conductivity,
Soil-water-plant relationships.
Controlled irrigation management of moderate to poor quality water must assure
sufficient movement of solution through the root zone to maintain a salinity
regime which a crop can tolerate while at the same time minimizing the deteriora-
tion of groundwater or river quality. The work reported here analyzes the major
plant-soil-salinity interactions resulting from irrigation with saline water at
controlled leaching fractions. Simulations are run for leaching fractions of
0.30, 0.05, and 0.01 and three different water uptake patterns for two high-sul-
fate waters with different salinity levels: 2.1 and 6.6 mmho/cm. Results
suggest that soil hydraulic conductivity and water retention should not be ad-
versely affected by high sodium levels or cumulative salt precipitation even at
very low leaching fractions. However, it is probable that plant activity will
be impaired by the lower leaching fractions because of high osmotic pressure
within the root zone and that root proliferation could be reduced by soil struc-
ture cementation resulting from salt precipitation.
78:030-004
GRAPEFRUIT RESPONSE TO VARIABLE SALINITY IN IRRIGATION WATER AND SOIL,
Bielorai, H., Shalhevet, J., and Levy, Y.
Institute of Soils and Water, Agricultural Research Organization, The Volcani
Center, Bet Dagan, Israel, Division of Environmental Physiology and Irrigation.
Irrigation Science, Vol. 1, No, 1, August, 1978, p 61-70. 3 fig, 4 tab, 16 ref.
Descriptors: Saline water, Irrigation water. Salinity, Crop response, Grapefruit,
Osmotic pressure, Salts, Leaching, Saline soils.
Results were reported from a long-term field experiment designed to determine the
effect of irrigation water salinity on the yield and water uptake of mature grape-
fruit trees. Treatments were started in 1970 and consisted of chloride concen-
trations in the irrigation water of 7.1, 11.4 and 17.1 meq/1 added as NaCl +
CaC12 at a 1:1 weight ratio. For the last four years of the experiment, 1973 to
1976, yield was linearly related to the mean chloride concentration in the soil
saturation extract weighted according to the distribution of water uptake with
depth and time. There was a 1.45% yield reduction for each 1 meq/1 increase in
chloride concentration above a threshold value of 4.5 meq/1. This corresponded
to a 13.5% decrease per 1 mmho/cm increase in the electrical conductivity of the
soil saturation extract above a threshold value of 1.2 mmho/cm. Total water up-
take was reduced as salt concentration in the soil increased. Salt accumulation
in the soil depended on the quantity and salt concentration of the irrigation
water, rainfall, and on the amount of leaching. No leaf symptoms of either Cl(-)
or Na(+) injury were observed. The results indicate an osmotic—rather than a
specific ion effect—of salinity on grapefruit yield.
78:030-005
SALT TOLERANCE IN THE WILD RELATIVES OF THE CULTIVATED TOMATO: RESPONSES OF
SOLANUM PENNELLII TO HIGH SALINITY,
Dehan, K., and Tal, M.
Ben Gurion University of the Negev, Beer Sheva, Israel, Department of Biology,
Irrigation Science, Vol. 1, No. 1, August, 1978, p 71-76. 5 tab, 12 ref.
Descriptors: Salt tolerance, Salinity, Tomatoes, Moisture deficit, Ions,.
Saline soils.
The cultivated tomato Lycopersicon esculentum/ cultivar Rheinlands Ruhm, and the
wild species Solanum pennellii accession Atico, were compared with respect to
their salt tolerance. The wild species was found to be more salt tolerant than
the cultivated tomato. In contrast to L. esculentum plants, the growth of the
wild species was not impaired by the high salinity, although the latter accumulated
more C1C-3 and Na(-i-) ions and its K+ level decreased under salinity. The smaller
increase in water deficit under salinity in the wild species was attributed to
its higher accumulation of ions.
112
-------
78:030006
DRAINAGE PRACTICE IN IMPERIAL VALLEY,
Hermsmeier, L.F.
Imperial Valley Conservation Research Center, United States Department of
Agriculture-Agricultural Research Service, Brawley, California.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 1, p 105-109, February 20, 1978. 1 fig, 7 tab, 10 ref.
Descriptors: Salinity, Drainage practices, Drainage, Drainage programs, Colorado
River Basin, Saline water, Water quality. Salt balance, Colorado River,
California.
The Imperial Valley in California has been irrigated by Colorado river water from
the start of the century. The irrigation water quality was recognized as
presenting possible drainage and salinity problems. As early as in 1902, irriga-
tion engineers of the United States Department of Agriculture indicated that
the water table and salinity of the valley needed to be controlled. Even to
this day, the salinity remains to be a problem in the Imperial Valley. The
purpose of this paper was to describe briefly all the drainage studies and develop-
ments that have taken place until the recent years. It also reports the soil
types, climate, drainage cost and the crops grown in the valley.
113
-------
SECTION XIV
WATER SUPPLY AUGMENTATION AND CONSERVATION
CONSERVATION IN'DOMESTIC AND MUNICIPAL USE (GROUP 03D)
78:030-001
ESTIMATION OF URBAN IRRIGATION WATER USE AND REQUIREMENT,
Fok, Y-S., and Murabayashi, E.T.
Hawaii University, Honolulu, Department of Civil Engineering.
Paper No. 78-2030, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 7 p. 7 ref,.l equ.
Descriptors: Water conservation. Irrigation water. Landscaping, Consumptive use,
Water requirements, Aesthetics, Water utilization, Vegetation, Estimating,
Methodology.
The difference between normal urban irrigation water use and the consumptive use
requirement is the potential amount of water that might be saved without ad-
verse economic consequences to urban property values. These savings fit the
general demand on better urban water use efficiency and/or urban water conserva-
tion. Methods for the estimation of urban irrigation water use and requirement
are presented in this paper.
114
-------
SECTION XV
WATER SUPPLY AUGMENTATION AND CONSERVATION
CONSERVATION IN AGRICULTURE (GROUP 03F)
78:03F-001
MANAGEMENT OF IRRIGATED SOYBEANS ON A MODERATELY COARSE-TEXTURED SOIL IN THE UPPER
MIDWEST,
Cassel, O.K., Bauer, A., and Whited, D.A.
North Carolina State University, Charlotte, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 1, p 100-104, January-February, 1978. 2 fig, 4
tab, 22 ref.
Descriptors: Soybeans, Supplemental irrigation, Water management (applied), Fer-
tilization, Nitrogen, Nitrates, Tensiometers, Leaching, Irrigation programs.
The objectives of this study were to determine the yield potential of supplementally
irrigated soybeans on moderately coarse-textured soils and to develop an irrigation
schedule for efficient water management. The study, conducted on Maddock sandy
loam from 1972 to 1974, employed a split-split plot design with water level as the
main block and N fertility rates (0, 56, 112, and 224 kg/ha) as subplots. Water
levels were Wl (dryland), W2 (underirrigation), W3 (optimum) and W4 (overirrigation).
Sub-subplotS were planting dates in 1972 and cultivars in 1973 and 1974. Grain
yields were significantly different for water levels during each of the three years.
Three-year yield means were 543, 1,823, 2,428,'and 2,164 kg/ha for Wl, W2, W3,
and W4, respectively. The application of 224 kg/ha N fertilizer in 1972 increased
grain yield at the 0.95 probability level. An irrigation scheduling based upon
tensiometers proved effective in applying irrigation water. Based upon results
of this study, it was concluded that soybeans can be seriously considered as a
crop to be included in cropping systems for irrigated, moderately coarse-textured
soils in the Upper Midwest.
78:03F-002
EFFECTS OF CULTURAL PRACTICES ON GRAIN YIELD OF IRRIGATED WHEAT,
Day, A.D., Jackson, E.B., and Alemu, A.
Arizona University, Tucson, Department of Plant Sciences.
Agronomy Journal, Vol. 70, No..2, p 279-282, March-April, 1978. 4 tab, 21 ref.
Descriptors: Wheat, Cultural control, Nitrogen, Fertilization, Crop production,
Planting management, Beds, Irrigation.
Experiments were conducted at Yuma, Arizona, to study the effects of N fertilizer
treatments in combination with methods of planting and row positions on beds, on
the yield and quality of wheat grain. Six N fertilizer treatments (34, 17 + 17,
68, 34 + 34, 136, and 68 + 68 kg/ha), two methods of planting (on the flat and on
beds) , and four row positions on beds (north, south, east, and west) were evaluated.
Flat plantings resulted in higher wheat grain yields than did bed plantings;
however, bed plantings produced higher grain volume-weights. -Within planting
methods, N fertilizer treatments did not significantly influence grain yields or
grain volume-weights. Grain yield components were similar for both planting
methods. Wheat grown on beds with an east-west orientation produced more heads
per unit area, more seeds per head, and higher grain yields than did wheat pro-
duced on beds oriented in a north-south direction. Wheat responded to N fertili-
zation when grown on both flat and bed plantings during the winter months in the
Southwest.
78:03F-003
EFFECT OF FERTILIZATION ON PENNCROSS CREEPING BENTGRASS,
Waddington, D.V., Turner, T.R., Duich, J.M., and Moberg, E.L.
Pennsylvania State university, University Park, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 5, p 713-718, September-October, 1978. 2 fig, 7
tab, 15 ref.
115
-------
Descriptors: Fertilization, Turf grasses, Fertility, Productivity, Nitrogen,
Phosphorus, Potassium, Soil tests.
A field study was conducted on fine, mixed soil to determine the effects of N
sources (agrinite, Milorganite, ureaform, and urea), P rates (0, 0.49, 0.98, and
1.95 kg/100 m2), and K rates (0, 0.76, and 1.52 kg/100 m2) on soil nutrient levels
and the growth, quality, and chemical composition of "Penncross" creeping bentgrass
(Agrostis palustris Huds.) maintained as putting green turf. Wilting, disease,
chlorosis, and annual bluegrass (Poa annua L.) infestation were used to assess
quality. Fertilization with Milorganite increased available soil P and Mg.
Application of K increased both tissue and available soil K. However, a greater
increase in soil K and a smaller increase in tissue K were obtained by the second
additional increment of K than the first one. The greatest change in tissue P
occurred with the first incremental addition of P. Tissue P was not greatly
affected by soil P above 224 ppm. Less severe summer wilting was observed with
Agrinite, Milorganite, and K treatments. Annual bluegrass invasion was favored
by P and K fertilization and the effect of one was enhanced by the other. Mil-
organite, which increased soil P, also favored annual bluegrass.
78:03F-004
EFFECTIVENESS OF NITRAPYRIN IN CONTROLLING NITRIFICATION OF FALL AND SPRING-
APPLIED ANHYDROUS AMMONIA,
Hendrickson, L.L., Walsh, L.M., and Keeney, D.R.
Wisconsin University, Madison, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 5, p 704-708, September-October, .1978. 4 tab, 18
ref.
Descriptors: Nitrification, Inhibitors, Denitrification, Nitrogen, Ammonia, Crop
response, Fertilizers, Corn (field).
Fertilizer N applied in the fall for the next growing season is often less
efficient than N applied closer to the time of plant use. Efficiency might be
greatly improved by maintaining the N as NH4, through the use of the nitrification
inhibitor, Nitrapyrin t2-chloro-6 (trichloromethyl) pyridine]. To evaluate this
hypothesis, field trials were established during 1975 to 1977 in south central
Wisconsin using 84 to 168 kg/ha N applied as anhydrous ammonia with and without
0.55 kg/ha Nitrapyrin. The results indicated that while nitrification can be
significantly slowed by application of nitrapyrin, a yield response does not
result. It was thought that a response might have been obtained had a crop been
grown on the poorly-drained area adjacent to the harvested area since appreciable
N appeared to have been denitrified at this site. Nitrification inhibition by
nitrapyrin varied widely within the same field. The results illustrated the
problems involved in predicting whether nitrapyrin application will be effective
in reducing nitrogen losses and increasing yields,
78:03F-005
EVALUATION OF NITRAPYRIN AS A MEANS OF IMPROVING N EFFICIENCY IN IRRIGATED SANDS,
Hendrickson, L.L., Keeney, D.R., Walsh, L.M., and Liegel, E.A.
Wisconsin University, Madison, Department of Soil Science.
Agronomy Journal, Vol. 70, No. 5, p 699-703, September-October, 1978. 3 fig, 5
tab, 24 ref.
Descriptors: Nitrification, Inhibitors, Nitrogen, Ammonia, Nitrates, Fertilizers,
Potatoes, Leaching, Osmotic pressure.
The objective of this research was to determine if optimum levels of N might be
maintained throughout the growing season by delaying nitrification with a nitri-
fication inhibitor, Nitrapyrin. Several field experiments were conducted oh a
Plainfield loamy sand involving various N sources, rates, and times of application
with and without Nitrapyrin. Potato tuber yield and the forms and distribution
of N in and below the fertilizer bands were determined. Nitrapyrin extended the
persistence of applied NH4 in all experiments, but inhibition of nitrification wasof
relatively short duration. Nitrapyrin persistence was likely reduced by the more
rapid volatilization and hydrolysis in sandy soils. Further, the effectiveness
of Nitrapyrin was likely limited by rapid leaching NH4 out of the Nitrapyrin-
treated zone. Application of Nitrapyrin reduced both total tuber yield and the
proportion of marketable tubers. The soil sampling data showed that Nitrapyrin
maintained a much higher NH4-N/NO3-N ratio than comparable nonnitrapyrin treatments-
•116
-------
It appears that the predominance of NH4-N interfered with plant metabolism so
that both yield and normal development of tubers were impaired.
78:03F-006
ZINC NUTRITION OF RICE AS INFLUENCED BY RATES OF GYPSUM AND ZN FERTILIZATION OF
ALKALI SOILS,
Takkar, P.N., and Singh, T.
Punjab Agriculture University, Ludhiana, Department of Soils.
Agronomy Journal, Vol. 70, No. 3, p 447-450, May-June, 1978. 2 fig, 2 tab, 15
ref, 2 egu.
Descriptors: Rice, Nutrient requirements, Zinc, Gypsum, Alkaline soils, Crop
response, Fertilization, Reclamation, Submerged plants.
Three field experiments were conducted on Zn deficient alkali soils, two on
Natraquic calciorthids, and one on Aquic Camborthids, to determine the effect of
gypsum and Zn fertilization alone and in combination on the Zn nutrition of rice
IR 8. Three rates of gypsum and three rates of Zn and their possible combinations
were tried. At all the three locations, the growth of the rice crop was very
poor and exhibited Zn deficiency symptoms in control plots. The yield and Zn
uptake was higher in alkali soil high in CaCO3 and low in pH than in soils low
in CaCO3 and high in pH. Gypsum application markedly decreased the available
Zn from deficient to adequate levels. Optimum response of rice to Zn was ob-
served at 11.2 kg Zn/ha except in one of.the Nitraquic calciorthids where it was
22.4 kg Zn/ha. The beneficial effect of Zn application to rice grown on the
alkali soils under investigation was far more than that of gypsum.
78:03F-007
RADIATION AND ENERGY BALANCE OF SPRINKLER AND TRICKLE IRRIGATED FIELDS,
Ben-Asher, J., Fuchs, M., and Goldberg, D.
Ben-Gurion University, Beer Sheva, Israel, Institute of Soil and Water.
Agronomy Journal, Vol. 70, No. 3, p 415-417, May-June, 1978. 1 fig, 2 tab, 13
ref, 8 equ.
Descriptors: Water conservation, Sprinkler irrigation, Tomato, Evaporation,
Energy budget, Evapotranspiration, Radiation, Albedo.
Water conservation claims in favor of trickle irrigation are poorly documented.
The radiation and energy balance of tomatoes grown on sand dune soil and on bare
soil irrigated by sprinkling and trickling were compared. Under trickle irrigation,
the average ratio of five energy balance measurements of evapotranspiration over
evaporation pan (Class A) was 0.3, compared with 0.60 obtained under sprinkler
irrigation. The comparison of radiation balance over the trickle and sprinkler
irrigated plots indicates that the increased radiant heat loss and albedo from the
dry portion of the trickle irrigated plot decreases the available evaporative
energy at ground level. The smaller radiant heat load combines with the resis-
tance of the dry soil to water flux to reduce the evaporation of the trickle
irrigated plot.
78:03F-008
INFLUENCE OF WATER AND FERTILIZER MANAGEMENT ON YIELD AND WATER-INPUT EFFICIENCY
OF CORN,
Rhoads, F.M., Manse11, R.S., and Hammond, L.C.
Florida University, Quincy, Department of Soil Sciences.
Agronomy Journal, Vol. 70, No. 2, p 305-308, March-April, 1978. 2 fig, 4 tab, 9 ref.
Descriptors: Corn (field), Water management (applied), Fertilizers, Nutrients,
Irrigation, Leaching, Soil-water-plant relationships.
This study was conducted to evaluate efficiency of water input in terms of corn
grain yield per unit of water, with two fertilizer application methods under three
soil-water management systems on a Troup loamy sand. Water management consisted
of (a) control—natural rainfall only, (b) trickle irrigation scheduled daily
(0.64 cm/day), and (c) trickle irrigation scheduled by tensiometer (1.30 cm/
application). Tensiometers were placed in each treatment at six depths between
15 and 150 cm below the soil surface and rea'dings were recorded daily. Methods
117
-------
of applying fertilizers were designated (a) conventional—1/3 of N and all P and
K applied broadcast preplant, and remainder of N applied in two sidedressings;
(b) program fertilization—N-P-K applied broadcast in small increments (5, 5, 10,
20, 20, 20, and 20%) at two-week intervals after corn emerged. Average grain
yields for the above water management treatments were 2,790, 4,160, and 5,700 kg/
ha respectively. Highest irrigation water-input efficiency (150 kg/ha/cm)
occurred with program fertilization and tensiometer scheduled irrigation. Irri-
gation water-input efficiency was lowest (10 kg/ha/cm) with corn receiving daily
irrigation and conventional fertilization.
78:03F-009
ECONOMIC ANALYSIS OF IRRIGATION PRODUCTION FUNCTIONS: AN APPLICATION OF LINEAR
PROGRAMMING,
Pomareda, C.
International Bank for Reconstruction and Development, Washington, D.C., Develop-
ment Research Center.
Water Resources Bulletin, Vol. 14, No. 1, p 24-34, February, 1978. 1 fig, 4 tab,
9 ref.
Descriptors: *Economic analysis, *Irrigated agriculture, "Linear programming,
*Water utilization, *Production function, Optimization, Resource allocation,
Profit, Crops, Mathematical models.
For estimating the yield response to irrigation water, good and varied information
is available; however, little and only partial (for individual crops) economic
analysis has been made of this information. Herein, the economic analysis of
irrigation production functions is discussed and a modified separable linear
programming model is used for examining optimal levels of water use when, at the
farm level, various crops with different water response functions compete for the
same scarce resource. The effects of alternative water availabilities on the
optimal levels of water use are explored using a multicrop farm model in which,
in principle, the full water response function for each crop can be included. The
farm objective function is specified as the maximization of profits from various
crops, given a restriction in the availability of water and other inputs. This
method provides advantage over the partial one-crop type of analyses because it
captures intercrop, tradeoffs in water and land use in response to economic policies
or changes in water supply.
78:03F-010
NITROGEN BALANCES FOR THE SANTA MARIA VALLEY,
Lund, L.J., Ryden, J.C., Miller, R.J., Laag, A.E., and Bendixen, W.E.
California University, Riverside, Department of Soil and Environmental Sciences.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 395-413, May 15-18,
1978. 6 tab, 7 ref.
Descriptors: Nitrogen, Nutrient removal, Denitrificatiqn, Vegetable crops,
Leaching.
A simplified steady-state model has been used to develop nitrogen balances in the
Santa Maria Valley, California. Balances have been developed for selected manage-
ment units and for the valley as a whole. The balance developed for a field
cropped with vegetables for the past twelve years showed that 30% of the applied
nitrogen was removed in harvested crop, 37% was leached below the root zone and
33% was unaccounted-for, which was attributed to gaseous losses of nitrogen as
products of denitrification. Direct field measurement of denitrification over an
eight-month period at one site in the same field found a 29% loss of the applied
nitrogen. The first estimation of the nitrogen balance in the valley attributed
24% of the applied nitrogen to removal in harvested crops, 39% to leaching and 37%
to denitrification.
78:03F-011
ECONOMIC CONCEPTS AND POLICIES RELATED TO CONTROLLING NONPOINT SOURCE POLLUTION
STEMMING FROM AGRICULTURE,
Whittlesey, N.K., and Barkely, P.W.
Washington State University, Pullman, Department of Agricultural Economics.
Proceedings of National Conference on Management of Nitrogen in Irrigated
118 •
-------
Agriculture, California University, Sacramento, California, p 333-353, May 15-18,
1978. 14 ref.
Descriptor: Pollution abatement.
This paper describes the role of economics in solving nonpoint source pollution
problems in terms that are understandable for the noneconomist. An economist
attempts to watch over the process of converting natural resources into marketable
commodities to assure that the process achieves the greatest possible good for
members of society. Economic tools are well equipped to handle this process for
goods and resources known as private property, those items used exclusively by the
individual owners. Unfortunately, most pollution problems occur through the use
and misuse of public property, those items owned and used jointly by all members
of society. Air and water are the most common examples of public property. The
paper describes economic concepts and public policies that are useful for inter-
nalizing the costs caused by pollution and abating or solving pollution caused
problems. The concepts of opportunity cost and income distribution and their
role in pollution abatement are discussed. Methods of choosing levels of abate-
ment include the extremes of zero pollution and that which can be achieved by
best management practices. The economic and social optimum probably lies between
these extremes. Arbitrary standards are sometimes imposed as a compromise between
the extremes of zero pollution and no abatement in an effort to approximate optimal
levels of abatement.
78:03F-012
DIAGNOSTIC TECHNIQUES USED TO IDENTIFY OPTIMUM LEVELS OF NITROGEN FERTILIZATION
FOR IRRIGATED CROPS,
Jackson, T.L.
Oregon State University, Corvallis, Department 'of Soil Science.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 321-332, May 15-18,
1978. 27 ref.
Descriptors: Nitrogen, Fertilization, Irrigation water, Nitrates.
The nitrogen available for plant growth comes primarily from 1) the nitrogen
released from soil humus and crop residues, 2) nitrogen added as commercial ferti-
lizers and 3) residual inorganic nitrogen from previous growing seasons or pre-
vious crops. Irrigation ensures adequate moisture and relatively uniform yields
from year to year. Irrigation also makes feasible the application of fertilizer
nitrogen during the growth of the crop and this provides the opportunity to use
soil and plant analysis early in the crop season to assess nitrogen needs.
Examples of the use of diagnostic techniques for estimating the fertilizer nitro-
gen required to supplement residual nitrogen levels and the capacity of the soil
to release nitrogen are presented.
78:03F-013
USE OF MATHEMATICAL RELATIONSHIPS TO DESCRIBE THE BEHAVIOR OF NITROGEN IN THE
CROP ROOT ZONE,
Davidson, J.M., and Rao, P.S.C.
Florida University, Gainesville, Department of Soil Science.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 291-319, May 15-18,
1978. 7 fig, 3 tab, 27 ref, 7 equ.
Descriptors: Nitrogen, Denitrification, Root 2one, Soil water movement, Mathemati-
cal studies.
A procedure to estimate the movement of water-soluble nitrogen species (N03 and
NH4) was developed by assuming that (i) the soil-water residing in all pore-
sequences participates in the transport process, and that (ii) the soil-water
initially present in the soil profile was completely displaced ahead of the
water entering at the soil surface. Field-capacity and initial soil-water con-
tent distribution in addition to total water inputs were necessary parameters to
estimate solute transport in the root zone. First-order kinetics were assumed to
describe the nitrogen transformations (mineralization, immobilization, nitrifica-
tion, and denitrification). These transformation processes were considered to
119
-------
occur under ideal conditions. Plant uptake of water and nitrogen (nitrate
and ammonium) was estimated, respectively, from potential evapotranspiration and
nitrogen uptake rate under ideal environmental conditions for a given crop. Actual
plant uptake of water and nitrogen was dependent upon the available soil water
and total mineral nitrogen within the crop root zone. These mathematical rela-
tionships could be solved using a programmable desk-top calculator; however, a
larger computer was needed when more complex submodels were employed to describe
soil-water uptake. The proposed mathematical relationships can provide field
managers and regulatory personnel with an integrated description of the behavior
of nitrogen in the root zone during a crop growing season.
78:03F-014
MONITORING WATER FOR NITROGEN LOSSES FROM CROPLANDS,
Tanrji, K.K.
California University, Davis, Department of Land, Air and Water Resources.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 251-263, May 15-18,
1978. 10 ref.
Descriptors: Nitrogen, Return flow, Irrigated lands, Monitoring, Water quality.
This paper reviews monitoring for nitrogen in surface and subsurface return flows
from irrigated lands. Presented are the elements of a monitoring program:
objectives of monitoring, parameters to be measured, sampling programs that in-
clude site selection, sampling frequency and sampling method, laboratory methods
for nitrogen determinations, requirements for resources and facilities, evaluations
of collected data and other support information and data, and dissemination of
monitored results. Each of these elements are appraised and a conclusion is
drawn on monitoring waters for nitrogen losses from croplands.
78:03F-015
EFFECT OF WATER MANAGEMENT ON NITRATE LEACHING,
Letey, J., Biggar, J.W., Stolzy, L.H., and Ayers, R.S.
California University, Riverside, Department of Soil and Environmental Sciences.
Proceedings of National Conference on Management o-f Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 231-249, May 15-18,
1978. 4 fig, 3 tab.
Descriptors: Nitrates, Leaching, Water pollution, Water management, Nitrogen,
Fertilization, Effluents, Correlation analysis.
*
Nitrates which are leached (transported below the root zone) represent a resource
loss and a potential contribution to water pollution. The amounts of leached
nitrates for a given time period were determined at various commercial farming
sites in California and in a carefully controlled experimental plot receiving
various water and fertilizer application treatments. Some of the agricultural
sites had tile drainage systems and others had "free drainage" to the groundwater.
Linear regression analyses were conducted on the data. Similar results were
observed for the tile and free drainage systems. The highest correlation coeffi-
cient was for amount leached versus drainage volume followed by amount leached
versus fertilizer nitrogen application. In most cases there was no significant
correlation between nitrate concentration in the water below the root zone and
drainage volume or fertilizer nitrogen application. A significant linear relation-
ship between amount of leached nitrate and drainage volume was also obtained at
the experimental plot.
78:03F-016
LEACHING OF NITRATE FROM SOILS,
McNeal, B.L., and Pratt, P.P.
Washington State University, Pullman, Department of Agronomy and Soils.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 195-230., May 15-18,
1978. 4 fig, 5 tab, 35 ref.
Descriptors: Nitrates, Nitrogen, Leaching, Irrigated land, Denitrification,
Waste disposal.
120
-------
Calculation of soil solution nitrate concentrations, and of mass emissions of
nitrate, are illustrated. Estimation of average water flux from nitrate/chloride
ratios, and from drain field outflows, are discussed. The high potential for
nitrate leaching from irrigated animal and municipal waste disposal sites is
mentioned, with stress being placed on the high denitrification potential at
many such sites, because of high soluble carbon loadings, high soil microbe
levels, and rapid oxygen depletion. Root zone and subsoil nitrate-nitrogen
values are provided for typical croplands of southern California and central
Washington. Such values are related to irrigation management and to downward
water flux. Crop differences in ability to utilize all soluble nitrate from the
soil solution are stressed, and some management alternatives for preventing deep
percolation losses of nitrate are detailed. Predictions of nitrate leaching losses
from data for nitrogen application rate and drainage water volume are discussed.
Typical predictions are presented and are compared to experimentally-measured
values. Overpredictiori of nitrate leaching estimates for some furrow-irrigated
tracts in the Pacific Northwest is demonstrated.
78:03F-017
VOLATILE LOSSES OF NITROGEN FROM SOIL,
Rolston, U.E.
California University, Davis, Department of Land, Air and Water Resources.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 169-193, May 15-18,
1978. 4 fig, 18 ref.
Descriptors: Denitrification, Volatility, Nitrogen, Fertilization.
Nitrogen may be lost from soil inlhe gaseous form by two major mechanisms, ammonia
volatilization and denitrification. Ammonia gas may be lost to the atmosphere
whenever ammonium compounds are applied to the soil surface. The greatest ammonia
losses occur from calcareous soils at high soil pH. Fertilizers such as urea and
ammonium sulfate result in greater ammonia loss than that from ammonium nitrate
when applied to a moist soil surface. More than 50% of the applied fertilizer may
be lost by ammonia volatilization if precautions are not taken. The best solution
for minimizing ammonia loss is to incorporate or place ammonium compounds approxi-
mately 10 cm below relatively dry surface soil. The volatile products of denitri-
fication, nitrous oxide and nitrogen gas, may be lost from the soil whenever the
soil becomes wet enough that oxygen becomes depleted and sufficient carbon is
available from organic materials to support microbial activity. Denitrification
occurs significantly only over a very narrow soil-water content range near
saturation and in those portions of the soil profile with fairly high organic
material. Consequently, denitrification will generally only occur in the surface
60 cm of most soils of arid regions unless perched water tables exist at a buried
surface horizon. Management practices to either minimize or maximize denitrifi-
cation should be directed at controlling nitrate position and water content in the
surface soil.
78:03F-018
REMOVAL OF NITROGEN BY VARIOUS IRRIGATED CROPS,
Tucker, T.C., and Hauck, R.D.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 135-167, May 15-18,
1978. 2 fig, 7 tab, 16 ref.
Descriptors: Nitrogen, Nutrient removal, Crop production, Fertilizers, Soil
management.
Harvested agronomic and horticultural plants, excluding rice, are grown under
irrigation on over 16 million hectares of land in 33 states. Results of a
survey of published and recent unpublished information on removal of soil and
fertilizer nitrogen from irrigated land in the harvested portion of crops was
presented. The amount of nitrogen removed varied considerably among different
plant species and within the same species when grown under widely different manage-
ment and environmental conditions. The amount of fertilizer nitrogen apparently
removed by grain crops generally was within the average range for all crops, 40
to 60% of the nitrogen applied. Fertilizer efficiency is discussed from three
121
-------
main viewpoints: in terms of (1) the amount of applied nitrogen found in the
plant, (2) the yield of harvested plant parts in relation to amount of fertilizer
nitrogen applied, and (3) the cash value of marketable crop in relation to nitro-
gen cost. Examples are given, using data for coastal bermudagrass and wheat, pf
fertilizer efficiency as calculated on the basis of these viewpoints. Methodo-
logical problems of collecting data and problems of data interpretation are dis-
cussed in relation to the several concepts of fertilizer efficiency, and emphasis
is placed on the need to recognize the role of all soil, fertilizer, and crop
management factors in determining the efficiency by which plants use nitrogen^.
78:03F-019
THE INDISPENSABLE ROLE OF NITROGEN IN AGRICULTURAL PRODUCTION,
Olson, R.A.
Nebraska University, Lincoln, Department of Agronomy.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 1-31, May 15-18,
1978. 10 fig, 2 tab, 35 ref.
Descriptors: Nitrogen, Fertilizers, Nutrients, Crop production, Crop response,
Pollutants.
The indispensable role of nitrogen in food and fiber production for the world's
people cannot be disputed. There is no substitute for nitrogen in its essential
roles as a component of the chlorophyll and protein constituents of crop plants.
The quantity required for obtaining an economic yield of most crops exceeds that
of all other soil-derived essential nutrients. The advent of relatively cheap
fertilizer nitrogen in the 1950's caused radical increases in yields obtainable
with most crops in the developed countries and provided the spark that ignited
the Green Revolution in many of the Less Developed Countries in the 1960's as
well. Its preeminence in the food production chain notwithstanding, nitrogen has
been subjected recently to more critical surveillance than any other element in
agriculture by reason of energy expended in its conversion into fertilizers, its
monetary cost to the farmer, and its potential role as environmental pollutant.
The economic and environmental problems can be minimized, however, by matching
rate and timing of applied nitrogen with the amount likely to be provided the
soil during the growing season and with the water regime afforded. The agricultur-
al sector must achieve this matching objective promptly if it is not to be
condemned by the rest of society in the long term.
78:03F-020
ASSESSING THE SPATIAL VARIABILITY OF IRRIGATION WATER APPLICATIONS,
Karmeli, D., Salazar, L.J., and Walker, W.R.
Colorado State University, Fort Collins, Colorado, Department of Agricultural
and Chemical Engineering.
Publication No. EPA-600/2-78-041, March, 1978. 201 p, 38 fig, 25 tab, 71 ref,
6 append.
Descriptors: Irrigation, Efficiency, Sprinkler irrigation.
The current state of the art regarding the spatial distributions of irrigation
water applications under surface, sprinkler, and trickle irrigation systems has
been assessed. The analyses found in the literature and several new uniformity
concepts have been integrated into models which can be used in both field and
research applications. These models stimulate the spatial distributions of applied
irrigation wat'er under specified design and operating conditions. The performance
of an irrigation system has been described by a series of "quality" parameters
relating to: (1) uniformity in an irrigated field; (2) adequacy of the irrigation
system in meeting crop requirements; (3) volume of applied water wasted as deep
percolation; and (4) in the case of surface irrigation, the water leaving the
field as tailwater. Verification of the models developed during this project was
made against most of tfte data identified in the literature as well as an intensive
collection effort as part of this project. The results illustrate both the use
of the analytical approach and the procedures for field data collection.
122
-------
78:03F-021
RELATIVE EVALUATION OF WATER STRESS INDICATORS FOR SOYBEANS,
Sivakumar, M.V.K., and Shaw, R.H.
International Crops Research Institute for Semi-Arid Tropics, Hyderabad 500 016,
India.
Agronomy Journal, Vol. 70, No. 4, p 619-623, July-August, 1978. 7 fig, 1 tab, 23
ref, 1 egu.
Descriptors: Soybeans, Soil-water-plant relationships, Moisture stress, Moisture
deficit, Growth rates, Plant growth, Soil water, Iowa, Indicators.
Field studies were conducted during 1976 on Ida silt loam (fine, silty, mixed
(calcareous) mesic family of Typic Udorthents) at the Western Iowa Experimental
Farm, Castana, Iowa, to evaluate three plant measurements (vis., stomatal conduct-
ance, leaf-water potential, and leaf area) as water stress indicators for soybeans
(Glycine max (L.) Merr.). Daily means of stomatal conductance and leaf-water
potential measured several times during the growing season were closely related
to changes in soil-water potential. "Rate of leaf-area expansion" which is
defined as the change in average leaf area (leaf area/number of leaves) per plant
over a period of time, also showed a close correspondence with soil-water potential.
Relative growth rates of soybeans showed a negative correlation with stomatal con-
ductance, leaf-water potential, and rate of leaf-area expansion. The three plant
measurements should prove useful in explaining water-deficit effects quantitatively
under field conditions.
78:03F-022
ACCUMULATION AND REDISTRIBUTION PATTERN OF DRY MATTER AND N IN TRITICALE AND WHEAT
VARIETIES UNDER WATER STRESS CONDITION,
Lai, P., Reddy, G.G., and Modi, M.S.
California University, Davis, Department of Land, Air and Water Resources.
Agronomy Journal, Vol. 70, No. 4, p 623-626, July-August, 1978. 1 fig, 3 tab, 16
ref.
Descriptors: Cereal crops, Wheat, Moisture stress, Varieties, Nitrogen, Economic
efficiency, Translocation, Moisture deficit, Crop production, Grains (crops).
The objective of this study was to screen varieties of triticale (Triticale hexa-
ploide Lar.) relative to wheat (Triticum aestivum L.) for their high translocation
ability and N utilization efficiency. A field experiment was conducted on silt
loam soil (Typic Hapludoll) during 1973-74 at Pantnagar, India. Treatments con-
sisting of five varieties each of triticale and wheat were arranged in a randomized
block design with five replications. Plant samples were collected from a 0.125-sq
m area for dry matter and N content studies in culm, lower leaf, flag leaf, spike
chaff, and grain at successive stages. The loss of dry matter from different plant
parts was assumed to be translocated to the grains. Both triticale and wheat
cultivars differed greatly in their capacity to accumulate and redistribute dry
matter and N. On an average, triticale cultivars removed larger amounts of N than
the wheat.
78:03F-023
INFLUENCE ON MANURE APPLICATION RATES AND CONTINUOUS CORN ON SOIL-N,
Magdoff, F.R.
Vermont University, Burlington, Department of Plant and Soil Science.
Agronomy Journal, Vol. 70, No. 4, p 629-632, July-August, 1978. 2 tab, 18 ref,
6 equ.
Descriptors: Corn(field), Decomposing organic matter, Organic matter, Nitrogen,
Crop response, Nutrient requirements, Rates of application, Sites.
The manure-N experiments with continuous corn (Zea mays L.) were conducted on both
a somewhat poorly drained Panton clay (Typic Ochraqualf) and a well-drained Calais
loam (Typic Fragiorthod). Manure rates of 0, 22, 44, and 66 metric tons/ha/year
were combined in factorial arrangement with ammonium nitrate rates of 0, 112, and
224 kg N/ha/year. Comparison of calculated theoretical soil-N with experimentally
determined levels after five years and the response of corn to fertilizer-N indi-
cate that mineralization of manure organic-N, when applied to the Panton clay, was
less than when applied to the Calais loam. Thus, manure-N was less available to
123
-------
the growing crop on the clay -and accumulated in the soil at a greater rate than
in the loam. The annual manure application rates required to maintain initial
soil N levels in Panton clay and Calais loam under continuous corn production were
calculated to be 40 to 52 tons/ha respectively. Two mineralization models were
examined: Model 1 assumed only the first year manure mineralization rate above
native soil organic matter decomposition rate; Model 2 assumed a five-year
mineralization decay series. Both were effective in predicting final soil-N
levels.
78:03F-024
INFLUENCE OF FERTILIZER AND RESIDUE MANAGEMENT ON GRASS SEED PRODUCTION,
Canode, C.L., and Law, A.G.
Washington State University, Pullman, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 4, p 543-546, July-August, 1978. 3 tab, 8 ref.
Descriptors: Grasses, Wheatgrass, Fescues, Bromegrass, Fertilization, Burning,
Air pollution.
The experiments were conducted on a silt loam soil (Pachi Ultic Haploxerolls) as
a split-plot within each grass species. Main plots were three levels of 18-10-
10-7 fertilizer applied to supply N at 90, 112, and 135 kg/ha, with an associated
increase in P, K, and S. Main plots were split for open burning and two levels
of mechanical residue removal. Two crops of red fescue and four seed crops of
smooth bromegrass and crested wheatgrass were evaluated. Average seed yields
(kg/ha) for burning compared with mechanical straw removal were 636 vs. 495 for
red fescue, 1,122 vs. 848 for smooth bromegrass, and 872 vs. 790 for crested
wheatgrass. Interactions of fertilizer rates and residue management were not
significant. The increase in seed production resulting from burning residue
apparently was associated with control of downy bromegrass (Bromus tectorum L.)
and increased vigor of autumn growth.
78:03F-025
RESPONSE OF CORN TO ZN IN ORTHO- AND PYROPHOSPHATE FERTILIZERS, AS AFFECTED BY
SOIL TEMPERATURE AND MOISTURE,
Giordano, P.M., and Mortvedt, J.J.
National Fertilizer Development Center, Tennessee Valley Authority, Muscle Shoals,
Alabama, Soil and Fertilizer Research Branch.
Agronomy Journal, Vol. 70, No. 4, p 531-534, July-August, 1978. 2 fig, 2 tab,
8 ref.
Descriptors:- Fertilizers, Phosphates, Sweet corn. Zinc, Phosphorus, Soil moisture,
Soil temperature, Crop response, Plant growth.
The purpose of this investigation was to determine the effects of both soil
temperature and moisture regimes on the uptake of Zn and P by corn (Zea mays L.)
from ZnS04, granulated with ammonium ortho- and polyphosphate fertilizers and
applied to Nolichucky scl (pH 7.6), a Typic Paleudult soil. In a series of green-
house experiments, corn grown under various soil temperature (16 to 32 C) and
moisture regimes (0.3 to 0.15 atm) showed a marked reduction in dry matter yield,
as well as in Zn and P uptake, at low temperature, but varying soil moisture levels
had little effect. Uptake of Zn was greater when triammonium pyrophosphate rather
than monoammonium phosphate was the source of applied P, but uptake of P-from
the two P sources was comparable. Although lower Zn uptake appears to be a
function of depressed growth under cool soil conditions, it is likely that
deficiency arises because early Zn requirements cannot be met when the available
Zn supply is low. Uptake and yield results further suggest that early growth
retardation sometimes attributed to Zn deficiency during cool springs also may
be related to suppression of P uptake.
78.-03F-026
RADIATION AND ENERGY BALANCE ON A TRICKLE-IRRIGATED LEMON GROVE,
Ben-Asher, J., and Sammis, T.W.
Arizona University, Tucson, Water Resources Research Institute.
Agronomy Journal, Vol. 70, No. 4, p 568-572, July-August, 1978. 4 fig, 2 tab,
7 ref, 7 equ.
124
-------
Descriptors: Water conservation, Irrigation, Irrigation systems, Energy budget,
Evapotranspiration, Lemons, Albedo, Radiation.
This study was conducted to evaluate the water saving potential and evapotranspi-
ration from a trickle irrigated lemon grove (Citrus limon L. "Lisbon"). Detailed
measurements of global, reflected, and net radiation and its dissipation above
the plant, the unshaded sandy soil, and the area as a whole were made in the
spring and summer of 1975. Two sources of radiant energy were observed: net
radiation which accounted for 70% of the energy utilized in evapotranspiration
and reflected radiation from the unshaded soil accounting for 30%. Experimentally
the net radiation and evapotranspiration of the wet complex increased as the
average net radiation and the evapotranspiration from the area as a whole de-
creased and vice versa. On the other hand, evapotranspiration and its ratio to
evaporation from a class A pan were smaller than any previously reported values.
Therefore, it is suggested that for these two periods the contribution of energy
from the dry area to the wet did not reflect a specific disadvantage for trickle
irrigation.
78:03P-027
YIELDS, NUTRIENT REMOVAL, AND NUTRIENT CONCENTRATIONS OF DOUBLE-CROPPED CORN
AND SMALL GRAIN SILAGE,
Murdock, L.W., and Wells, K.L.
Kentucky University, Lexington, Department of Agronomy.
Agronomy Journal, Vol. 70, No. 4, p 573-576, July-August, 1978. 7 tab, 7 ref.
Descriptors: Sweet corn, Barley, Oats, Silage, Crop response, Crop production,
Nutrient removal, Kentucky.
The study was initiated to determine production levels from double-cropped silage,
the most compatible small grain species for double-cropped silage, and the rate
and method of fertilizer application needed for high production. Field experiments
were established on Huntington (fine-silty, mixed mesic fluventic Hapludoll) and
Pope (coarse-loamy, mixed, mesic fluventic Dystrochrept) soils. Three fertility
levels were tested with 392-128-280, 280-89-232, or 168-54-140 kg/ha of N-P-K
being applied each year. Single and split applications of K were studied. Barley
(Hordeum vulgare L.) and oats (Avena sativa L.) were compared as small grain
species. This study indicates that double-cropped corn and small grain for
silage can result in substantially higher dry matter production per unit land
area than single-cropped corn. Large amounts of minerals are removed, however,
particularly K, by the small grain component of the double-cropping system.
78:03F-028
SUGAR BEET GENOTYPE, N, AND SOIL MOISTURE AVAILABILITY INTERACTIONS IN COMPONENTS
OF BEET YIELD AND QUALITY,
James, D.W., Doney, D.L., Theurer, J.C., and Hurst, R.L.
Utah State University, Logan, Department of Applied Statistics and Computer Science.
Agronomy Journal, Vol. 70, No. 4, p 525-531, July-August, 1978. 8 fig, 2 tab,
16 ref.
Descriptors: Sugar beets, Nitrogen, Soil moisture. Crop response, Crop production,
Varieties.
This study was conducted to investigate the genotype of sugar beet (Beta vulgaris
L.) X soil N and genotype X soil water interaction from a broad genetic base.
A series of 20 genetically different genotypes differing in yield, sugar percent,
and impurity index potential were field tested in 1974 at four N levels: 0, 84,
210, and 525 kg/ha. In 1975, eight genetically diverse genotypes were field
tested at five N levels and four irrigation levels. The soil type was coarse,
loamy mixed mesic family of calcic haploxerolls. Analysis of data were for root
yield, sucrose percent, gross sugar, and impurity index, Highly significant
main effects due to N in 1974 and 1975 and water in 1975 were observed for all
measured parameters. A significant genotype (V) X (N) interaction was obtained in
1974 for all parameters. There was an apparent genotype X water interaction in
1975; however, unbiased statistical inferences could not be made because of the
experimental design. These interactions indicate that genetic variation exists
such that new cultivars may be developed that give high sugar production at low
N levels or are not affected adversely in quality at a high N level.
125
-------
78:03F-029
INHIBITION OF UREASE ACTIVITY BY HETEROCYCLIC SULFUR COMPOUNDS,
Gould, W.D., Cook, F.D., and Bulat, J.A.
Alberta University, T6G 2E1, Edmonton, Alberta, Canada, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 1, p 66-71, January-February,
1978. 3 fig, 5 tab, 30 ref.
Descriptors: Urea, Nitrogen, Nitrification, Inhibitors, Sulfur compounds. Soil
investigations, Volatility, Hydrolysis.
The inhibition of both jack bean urease and soil urease by several heterocyclic
mercaptans was investigated. The following compounds not previously tested as
urease inhibitors were found to be effective inhibitors of jack bean urease:
1,3,4-thiadiazole-2,5-dithiol; 5-mercapto-3-phenyl-l,3,4-thiadiazole-2-thione;
and 5-amino-l,3,4-thiadiazole-2-thiol. The disulfides of the latter two com-
pounds were found to be very potent inhibitors of jack bean urease. The results
are consistent with an inhibition mechanism involving a thiol-disulfide exchange
reaction between a disulfide and one or more of the sulfhydryl groups of urease.
The results also imply that inhibition of urease by the heterocyclic mercaptans
was due to trace amounts of the corresponding disulfides or polysulfides in the
mercaptan preparations. A number of heterocyclic mercaptans, two disulfides,
and a number of known urease inhibitors were evaluated as soil urease inhibitors,
and the following compounds were the most effective: 1,4-benzoquinone; hydro-
guinone > 2,5-dimethyl-1,4-benzoquinone; catechol; 1,3,4-thiadiazole-2,5-dithiol;
2,6-dimethy1-1,4-benzoquinone.
78:03F-030
NONUNIFORM SPRINKLER IRRIGATION APPLICATION EFFICIENCY,
Chaudhry, F.H.
de Sao Paulo Universidade, Sao Carlos, Brazil, Department of Hydraulics and
Sanitary Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR2, p 165-178, June, 1978. 4 fig, 15 ref, 43 equ,
3 append.
Descriptors: Irrigation efficiency, Sprinkler irrigation, Uniformity coefficient,
Distribution, Statistical methods, Irrigation, Irrigation design.
Application efficiency offers a physically significant characterization of
nonuniform irrigation which can help in striking a balance between the cost of
maintaining higher uniformity and the cost of water. This paper quantifies the
role of asymmetry in the various efficiency parameters of nonuniform irrigation
representing its areal pattern by a skew distribution. It is shown that if the
application ratio or the coefficient of variation, or both, are small, the appli-
cation efficiency approaches the value of the application ratio. The equality
between the application ratio and the application efficiency can be obtained at
relatively larger coefficients of variation (or smaller uniformity coefficients)
for positively skewed distributions. Given the statistical properties of the
sprinkler or surface irrigation distribution and the proposed application ratio,
the results of this study should permit a more accurate evaluation of the appli-
cation efficiency and thus of the economics of the proposed installations.
78:03F-031
EFFECT OF IRRIGATION REGIME ON MAIZE YIELDS,
Barrett, J.W.H., and Skogerboe, G.V.
Colorado State University, Fort Collins, Department of Agriculture and Chemical
Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil Engineers/
Vol. 104, No. IR2, p 179-194, June, 1978. 9 fig, 2 tab, 20 ref, 1 append.
Descriptors: Yield equations, Sweet corn, Crop response, Moisture stress, Water
requirements, Growth stages, Evapotranspiration, Crop production, Irrigation,
Irrigation efficiency.
To determine the economically optimal allocation of irrigation water to a given
crop, the relationship between the yield of the crop and its use of the supplied
water must be known. Different shapes of the function relating yield to water
126
-------
use have been obtained by various researchers. The strongly linear relationship
between wheat grain yield and precipitation has been supported by container and
field experiments that have demonstrated for many crops a linear relationship
between yield and water use until maximum- yield is obtained. The purpose of
this paper is to present field evidence substantiating the form of the crop
yield-water use function and to demonstrate the effects of different irrigation
regimes on the yield of corn.
78:03F-032
WATER TREATMENTS IN TRICKLE IRRIGATION SYSTEMS,
Nakayama, F.S., Gilbert, R.G., and Bucks, D.A.
Agricultural Research Service, Phoenix, Arizona, Department of Agriculture.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IRl, p 23-34, March, 1978. 11 fig, 1 tab, 12 ref, 1
append.
Descriptors: Irrigation water, Water treatment, Irrigation systems, Clogging,
Orifices, Water quality, Water analysis, Water pollution control, Filtration,
Colorado River.
A comprehensive two-year study on trickle irrigation systems using Colorado River
water in southwestern Arizona has shown that adequate water filtration is a primary
requirement for reliable emitter operation. Filtration systems must be able to
handle local peak loads in suspended particulates from the source water. For
the long-term operation of the trickle system, the practice of flushing mains,
submains and lateral lines, and chemical water treatment is essential for control-
ling the buildup of sediment, precipitates, and microbial slime. Precautions
must be taken to ensure that the emitters, line materials, and other equipment
are resistant to chemicals such as fertilizer, bactericide, insecticide, and
herbicide that may be injected into the system.
78:03F-033
BASIC IRRIGATION SCHEDULING PROCEDURES,
Fischbach, P.E.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Irrigation Age, Vol. 12, No. 7, p 66-67, April, 1978. 2 fig.
Descriptors: Irrigation, Irrigation water, Scheduling, Soil moisture, Moisture
content, Growth stages, Sweet corn. Moisture meters, Evapotranspiration, Water
conservation.
On a fine textured deep soil, four basic irrigation scheduling procedures were
compared on corn. The procedures consisted of irrigations according to (1) the
calculated crop water use, (2)- the average electrical resistance block reaching,
(3) the soil moisture content (feel method) at three stages of growth of the
corn plant, and (4) a predetermined range of net water application every fourteen
days. The difference between grain corn yields were not significant at the 5%
level between scheduling procedures. The least effort to schedule irrigations
was with the electrical resistance blocks. Applying only 2 inches of net irri-
gation water or less each irrigation is important so that nitrogen, water or
energy is not wasted. Using a water measuring meter to know how much water was
applied appears to be the most critical measurement to save nitrogen, water and
energy.
78:03F-034
ON-FARM LEVEL-BASIN IRRIGATION—SAVE WATER AND ENERGY,
Dedrick, A.R., Replogle, J.A., and Erie, L.J.
Agricultural Research Service, Phoenix, Arizona, U.S. Department of Agriculture.
Civil Engineering, Vol. 48, No. 1, p 60-65, January, 1978. 8 fig.
Descriptors: Surface irrigation, "Basins, Irrigation efficiency, Irrigation
systems, Irrigation practices, Water distribution (applied), Energy loss, Water
conservation, Automation.
Spiraling energy costs, and the doubtful availability of electricity or natural
gas for pumping, stand as a serious threat to future high-energy-consuming water
127
-------
application techniques. Even with the growing concern for water conservation,
we may run out of energy before we run out of water. Surface irrigation,
because of its lower energy requirements, deserve renewed attention. Thus,
despite the merits of sprinkler and trickle irrigation, conversion from surface
irrigation should be approached cautiously, especially where properly designed
surface irrigation techniques are suitable. Uniformity of application and
resultant minimal water loss over the irrigated area are prime criteria of an
irrigation system. These can be attained with level basins by balancing the
basin size to the irrigation water supply and soil intake characteristics.
The key factors in boosting irrigation efficiencies are suggested as: (1)
using lasers to make the farm field as level as possible, (2) using special
flumes and weirs to measure water flow, and (3) using automated gates to control
the amount of water applied to a field.
78:03F-035
TAILWATER PITS GAIN POPULARITY IN TEXAS,
Blair, J.
Big Spring, Texas.
Irrigation Age, Vol. 12, No. 7, p 70-71, April, 1978. 4 fig.
Descriptors: Tailwater, Silts, Irrigation, Water conservation, Irrigation
practices, Crop production, Water shortage.
Tailwater pits are one of the best methods yet devised to save irrigation water
on the hardlands of northwest Texas and eastern New Mexico. Interest in them
is still high, though the construction rate has slowed because of rising costs
and the increase in sprinkler systems. In the recent years tailwater pits are
designed according to the size of the field and amount of expected runoff with
efficient silt traps. The report also suggests to check pump and motor
occasionally to increase their efficiencies. It also suggests to irrigate alter-
nate rows, learn when the crops go through stress periods, use limited tillage
to'reduce evaporation, improve tillage to reduce fuel costs, grow crops that
use less water, and go back to terracing the fields if necessary.
78:03F-036
"NO ROOM FOR ERROR" SAYS YOUNG IRRIGATOR,
Irrigation Age, Vol. 12, No. 5, p 77, February, 1978.
Descriptors: Crop production, Management, Agriculture, Idaho, Potatoes,
Fertilizers, Herbicides, Pesticides-
*
The total management approach towards agricultural crop production of a Idaho
farmer was discussed. The approach includes frequent soil and plant testing,
selection of good seed varieties, timely applications of fertilizers, herbicides,
and pesticides of the right kind and amount including a good crop rotation program.
78:03F-037
STUBBLE BURN SCORES,
Irrigation Age, Vol. 12, No. 4, p 16, January, 1978.
Descriptors: Burning, Infiltration, Infiltration rates, Crop production-, Econo-
mics, Adoption of practices, Comparative benefits, Comparative costs, Comparative
productivity.
A study conducted at Texas A & M University compared plots where the straw was
worked, where it was removed by bailing and where the straw and stubble was burnt
off. The results showed that the difference in yields from the three types of
plots was statistically insignificant. But the calculated annual savings from
burning off each year rather than bailing or working back into the soil was $4.02/
acre; whereas burning every other year and every third year could save $2.01 and
$1.34/acre respectively. Another study involving infiltration rate showed that
the infiltration rate for the burnt area was. slower in the first hour, but in-
creased later during a 22-hour-period.. Total infiltration for the period for
the plot with straw worked in was 2.58 inches compared with 2.50 for straw
removed and 2.28 inches for the burned area. The effect of straw disposal treat-
ments on soil structure including changes in soil aggregates, bulk density,
128
-------
gas,
organic matter and compaction was studied. Results of dry and wet sieve
analyses showed no significant differences among the three treatments.
78:03F-038
NEW MEXICO PUMP STUDY POINTS TO FARMERS' NEED FOR EFFICIENCY KNOWLEDGE,
Irrigation Age, Vol. 12, No. 4, p 34-35, 58, January, 1978. 3 tab.
Descriptors: Pump testing, Pumping plants, Pumps, Efficiencies, Natural
Operation and maintenance, New Mexico.
A New Mexico irrigation pump study suggests farmers should know more about
pump efficiency and should have expert help in selecting pumps. Overall effi-
ciency of a pumping plant, according to the report, should range from 15 to
20%. A study conducted by Texas Tech College which covered power requirements
and efficiencies of 46 natural gas pumps revealed that only € pumps exceeded
15% overall efficiency while 16 had overall efficiencies below 10% and the
average was 10.7%. The study conducted in New Mexico suggested that the average
pump efficiency could be improved to 15% and thereby about 1.4 million cubic
feet of natural gas used for irrigation pumping during an average year in New
Mexico could be saved. This report also provides some guidelines for studying
pumping plant efficiency.
78:03F-039
TENSIOMETERS TEACH HOW TO SAVE FUEL AND WATER,
Rodgers, N.
Littlefield, Texas.
Irrigation Age, Vol. 12, No. 4, p 45-46, January, 1978.
Descriptors: Tensiometers, Equipment, Data collections, Irrigation, Irrigation
efficiency, Soil moisture, Moisture tension, Moisture content, Water conservation.
Tensiometers axe valuable tools for the irrigator helping him to save money and
water during the irrigation season. The irrigation schedule, based on soil
moisture tension, can be varied during different periods of the growing season,
depending upon the water requirements of the plant. However, they can mislead
the irrigator if the tensiometers are not properly placed and maintained.
Reading tensiometers daily has been suggested since it will indicate the danger
of the tensiometers breaking suction and thus taking false readings can be
avoided.
78:03F-040
DRAINAGE AND THE CENTER PIVOT SPRINKLER METHOD OF IRRIGATION,
Alvi, A.A.
Valmont International, Valley, Nebraska 68064.
ICID Bulletin, Vol. 27, No. 1, p 76-78, January, 1978. 7 ref.
Descriptors: Sprinkler irrigation, Irrigation, Drainage, Flooding, Salinity.
The surface method of flood irrigation is a source of drainage problems and it
also does not provide controlled amounts of water to crops as and when required.
The Center Pivot Sprinkler method of irrigation helps to solve these problems
and has some other additional advantages. This method of irrigation in combina-
tion with integrated drainage construction is hoped to meet growing needs of
food and fiber for the increasing world population.
78:03F-041
DEVELOPMENT OF AGRICULTURAL IRRIGATION IN THE FEDERAL REPUBLIC OF GERMANY,
Zanker, K.
Federal Ministry sof Food, Agriculture and Forestry, Bonn, Regierungsdirektor.
ICID Bulletin, Vol. 27, No. 1, p 85-88, January, 1978. 3 tab, 4 ref.
Descriptors: Irrigation, Irrigation systems, Sprinkler irrigation. Water
conservation. Water shortage, Arid climates, Semiarid climates.
Although the Federal Republic of Germany is situated in the temperate zone and
owing to its quite high rainfall has no real water shortage in the strict sense
129
-------
of the term, modern irrigation methods do, however, offer the possibility of doina
the available water supply more rationally and more economically. This is parti-
cularly true for years with low rainfall. In granting new water rights,
the authorities should strive to reserve the supply of groundwater primarily for
drinking purposes. In most cases for irrigation, surface water or effluent is
sufficient (the latter, of course, subject to standards of hygiene being met).
The results of the present paper can be usefully applied to areas where a real
water shortage exists-arid and semi-arid zones of the earth. The more economical
use of water available, made possible by more modern irrigation methods, which
can lead to a considerable saving of water, can be of great importance, especially
when water is in particularly short supply.
78:03F-042
STANDARDS FOR THE CALCULATION OF IRRIGATION EFFICIENCIES,
ICID Committee on "Assembling Irrigation Efficiency Data."
ICID Bulletin, Vol. 27, No. 1, p 91-101, January, 1978. 6 tab, 6 egu.
Descriptors: Standards, Irrigation efficiency, Irrigation, Irrigation ditches,
Irrigation canals, Irrigated land, Irrigation design.
The efficient management of irrigation water is becoming more and more important
as the competition for water of good quality grows ever keener with the world's
increasing population. Reliable measurements of water are vital in preventing
wastage and in the attainment of maximum beneficial use. Measurements should be
made and records kept of all water flowing into and through the supply system and
of all deliveries made from the system. Discharge measurements should be made
as accurately as is practicable and action should be taken to restrain overdelivery-
The purpose of this paper is to lay down a standard procedure for assessing
efficiency of water use in conveyance, distribution and field application operations-
78:03F-043
DRIP SYSTEMS STANDARDS AND SPECIFICATIONS,
Irrigation Journal, Vol. 28, No. 3, p 12-13, 32, May-June, 1978.
Descriptors: standards, Specifications, Irrigation, Irrigation systems, Water
conservation, Irrigation design, Installation.
These standards and specifications of drip irrigation systems outlined by the
Florida Irrigation Society contains useful information and guidelines for the
irrigation industry.
78:03F-044
UNDER-TREE IRRIGATION SYSTEM,
Irrigation Journal, Vol. 28, No. 3, p 34, May-June, 1978.
Descriptors: Irrigation, Water conservation, Irrigation systems, Sprinkler
irrigation, Drainage, Leaching.
A paper entitled, "Irrigation in Ihe 21st Century-Today," which appeared in the
May/June 1976 issue of the Irrigation Journal, dealt with the advantages of the
Micro Jet and referred to it as the irrigation system of the future. The purpose
of this paper is to describe an Israeli emitter, or minisprinkler which has been
in operation for a number of years and also shows a great potential for the
future.
78:03F-045
DRIP AND/OR SPRINKLER,
Olson, B.R., Jr.
Olson Engineering System, Indio, California.
Irrigation Journal, Vol. 28, No. 3, p 46-47, May-June, 1978.
Descriptors: Water conservation, Irrigation systems, Sprinkler irrigation, Water
management (applied), Irrigation water, Filtration.
The purpose of this report is to discuss the various aspects of a drip irrigation
system associated with its applicability and how it compares with a sprinkler
irrigation system.
130
-------
78:03F-046
COMPUTER SCHEDULING CAN SAVE MORE WATER,
Irrigation Age, Vol. 12, No. 6, p 17, March, 1978.
Descriptors: Irrigation programs, Scheduling, Irrigation efficiency, Water
conservation, Computer models, Computer programs, Water management (applied),
Nebraska, Irrigation systems.
It is reported that scheduling of irrigation water application through the use
of electrical resistance blocks to determine soil moisture content, with data
feedback to a computer system, can save up to 38% of the water and energy being
used in most irrigation operations without reducing yields. One such irrigation
scheduling computer program developed at the University of Nebraska-Lincoln has
been discussed in this report.
78:03F-047
BETTER WATER USE, SAYS TEXANS,
Blair, J.
Big Spring, Texas.
Irrigation Age, Vol. 12, No. 6, p 26, March, 1978.
Descriptors: Water conservation, Irrigation, Irrigation wells, Texas, Irrigation
efficiency, Grain sorghum, Cotton, Drought resistance, Surface irrigation,
Sprinkler irrigation.
Irrigation on the Southern High Plains will continue the trends started a few
years ago when production costs escalated. There will be greater emphasis on
irrigation efficiency, more timely watering, fewer irrigations, and a slow-down
in buying of new equipment. Also there will be a shift in crop acreages, with
some of the corn and wheat land being put in milo and cotton. Consensus of
opinion of the farmers is that despite higher irrigation costs most farmers will
pump the wells in 1978. But there will be continued improvement in pumping effi-
ciency, more water conservation methods used, more dependence on rainfall and
a shift to drought resistant crops, such as cotton and grain sorghum.
78:03P-048
CORN YIELDS FROM IRRIGATION WITH ADEQUATE AND DEFICIENT WATER,
Kroutil, W.F.
Nebraska University, North Platte, Department of Agricultural Engineering.
Paper No. 78-2555, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 19 p. 11 fig, 2 tab, 25 ref.
Descriptors: Water management "(applied), Corn (field), Moisture deficit, Yield
equations, Crop response, Crop production, Growth stages, Evapotranspiration,
Water conservation, Irrigation efficiency.
In 1974 and 1975, the effects of varying the time and the amounts of applied
irrigation water on corn yield .was studied on field plots at Fort Collins,
Colorado. A single irrigation sprinkler line extending through the center of
each plot provided the sole source of irrigation water. With this irrigation
design, the corn experienced greater water deficiency outward from the sprinkler
line. . In addition, irrigation water was withheld from some treatments during
various growth periods throughout the season. The field plots were preplant
irrigatdd to wet the soil profile to a depth in excess of three meters. Primary
comparisons were made of actual and/or relative yields of grain and dry matter
for different water application amounts and for evapotranspiration. Omitting
irrigation water during certain growth periods generally reduced yields. High
soil water holding capacity reduced the necessity for frequent irrigation.
Omitting all irrigations during two growth periods reduced yields substantially.
Omitting irrigations was not always detrimental if adequate water was available
in the soil profile to maintain adequate evapotranspiration. Of major signi-
ficance was the result that, with few exceptions, regular application of less
irrigation water than that required for maximum evapotranspiration produced
the best water use efficiencies expressed as yield-per-unit of water consumptively
used.
131
-------
78:03F-049
IRRIGATE—A SCHEDULING MODEL,
Tscheschke, P., Gilley, J.R., Thompson, T., and Pischbach, P.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Agricultural Engineering, Vol. 59, No. 1, p 45-46, January, 1978. 1 fig, 4 ref.
Descriptors: Water conservation, Scheduling, Irrigation, Computer models, Timing,
Crop production, Computer programs, Crop production, Evapotranspiration, Climatic
data, Irrigation systems.
Irrigation is a major consumer of the three scarce commodities: energy, water,
fertilizer. The need for conservation through good irrigation management prac-
tices is urgent. To help meet these needs, University of Nebraska has developed
an irrigation scheduling program called IRRIGATE for its AGNET (Agricultural
Computer Network) system. The network serves the Institute of Agriculture and
Natural Resources at the University of Nebraska-Lincoln and benefits the agri-
cultural community directly. As with all AGNET models, IRRIGATE is designed for
teaching, research and extension work. Access to AGNET can be made through small
portable computer terminals. These are priced from $2000 and are about the size
and shape of a portable typewriter. IRRIGATE records a field's soil moisture
status since planting and answers the important questions of when and how much
water should be applied in future irrigations. IRRIGATE 'is designed to be user
oriented. IRRIGATE can be used with a wide variety of irrigation systems, with
nine commonly grown area crops, with eight common soil types and with a minimum
of climatic data (maximum and minimum temperature only) if necessary. The irri-
gation scheduling for about 25,000 acres was handled through IRRIGATE and AGNET
in 1977.
78:03P-050
DRIP IRRIGATION-CHEMICAL, PHYSICAL WAYS TO KEEP EMITTERS OPEN,
Crops and Soils Magazine, Vol. 30, No. 6, p 15-18, March, 1978. 9 fig.
Descriptors: Maintenance, Clogging, Irrigation systems, Water conservation,
Treatment, Chemical precipitation.
The most serious problem in drip irrigation is plugging of 'emitters caused by
chemical or biological buildup in minute water passageways. Preventing that
buildup is a key to successfully operating most drip irrigation systems. Re-
searchers at Yuma and Phoenix, Arizona approached the clogging problem and
reclaimed old drip lines by adding dilute H2SO4 and hypochlorite solution
(laundry bleach) to the irrigation water entering the lines. After the initial
"slug" treatment, the emitters were operating at 95% of the designed flow. After
the 24- to 36-hour treatment, the entire system was treated with lower concen-
trations of chlorine and acid, keeping the system at about 1 ppm chlorine and
a pH of 7. That continuous treatment maintained satisfactory emitter performance,
not only in the older lines but in a newly installed system. More research is
being done to expand guidelines for maintaining emitter performance.
78:03F-051
LIMITED IRRIGATION TESTS GET RESULTS,
Irrigation Age Magazine.
Irrigation Age, Vol. 12, No. 8, p 72-74, May-June, 1978. 2 fig.
Descriptors: Water conservation, Moisture deficit, Growth stages, Timing, Corn
(field), Irrigation practices, Sorghum, Soybeans, Kansas, Nebraska.
Limited irrigation experiments were conducted in Kansas and Nebraska on corn,
sorghum and soybean. It was observed by the researchers in the two states that
corn yield was reduced by limiting' irrigation at any stage of growth but a single
irrigation was most effective just before the silking stage. With soybeans, they
observed that the most critical period was at the beginning of pod development,
^whereas with sorghum, the timing of irrigation was not found to be important
which gives it a management advantage when using limited water. The experiments
showed that the limited irrigation techniques help in saving water, energy and
irrigation equipment,wear and tear.
132
-------
78:03F-052
HOW IDAHO IRRIGATORS TRIM BACK POWER COSTS,
Henry, C.
Irrigation Age Magazine.
Irrigation Age, Vol. 12, No. 8, p 82-84, May-June, 1978.
Descriptors: Scheduling, Irrigation, Irrigation practices/ Electric power costs.
Fertilizers, Water conservation, Crop production, Idaho, Water management (applied)
The ibenefits obtained by an Idaho farmer by irrigation scheduling were reported.
Irrigation scheduling has not only helped to keep the power cost down but also
it has reduced labor-hour requirement, leaching of fertilizers and has resulted
in increased yields. One other additional advantage was in management operations,
such as thinning and cultivations, during periods indicated by favorable moisture
content.
78:03F-053
FLOAT VALVES IMPROVE PIPELINE SYSTEMS,
Humpherys, A.
Snake River Conservation Research, Agricultural Engineering Division, Kimberly,
Idaho.
Irrigation Age, Vol. 12, No. 7, p 12-15, April, 1978. 1 fig, 1 tab.
Descriptors: Water conservation, Floats, Valves, Flow control, Pipelines, Water
shortage, Irrigation efficiency.
Water shortages and rising energy and labor costs are forcing irrigators to look
for ways to increase irrigation efficiency and reduce operating costs. To
accomplish this, they need maximum system flexibility and ease of operation.
Many low pressure pipeline systems can be improved by using float valves to
provide better and easier water control. Float valves are relatively new and
since most of them are used in California where they were developed, many
farmers are not familiar with them. This paper discusses the applicability of
float valves in various situations of field irrigation systems.
78:03F-054
DISTRIBUTION PATTERNS AND LOSSES FOR FURROW IRRIGATION,
Karmeli, D.
Colorado State University, Fort Collins, Department of Agricultural and Chemical
Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR1, p 59-68, March, 197R. 4 fig, 1 fig, 10 ref, 22
equ, 1 append.
Descriptors: Furrow irrigation, Surface irrigation, Distribution patterns,
Irrigation efficiency, Model studies, Mathematical models, Recession curves,
Infiltration, Runoff.
A model was developed to describe the distribution patterns and efficiencies for
furrow irrigation. The model consisted of the following: (1) A frequency
curve of the diraensionless infiltration depth (actual infiltered depth/desired
infiltration depth), versus fractional length of run (distance from end of field/
total length of field); (2) Description of the frequency curve by a mathematical
model that enables the comparison of systems by using the model to establish
the various efficiencies and other statistical parameters such as the deviation
from desired application depth. The model, based on the power curve fit for
surface irrigation systems, was found to be a good representation of actual
patterns of distribution in an irrigated field. The model suggested allows for
integration of the various functions related to irrigation performance such as
water-yield function.
78:03F-055
STRAW-MULCH RATE EFFECT ON SOIL WATER STORAGE AND SORGHUM YIELD,
Unger, P.W.
United States Department of Agriculture, Southwestern Great Plains Research
Center, Bushland, Texas 79012.
Soil Science Society of America Journal, Vol. 42, No. 3, p 486-491, May-June,
1978. 4 fig, 3 tab, 12 ref.
133
-------
Descriptors: Mulching, Water conservation, Moisture availability, Grain sorghum,
Moisture content, Fallowing, Crop response.
A field study was conducted to determine the effects of straw mulch rates on soil
water storage during fallow and on subsequent grain sorghum production. Wheat
straw at rates of O(check), 1, 2, 4, 8, or 12 metric tons/ha was placed on field
plots in July 1973, 1974, and 1975. A different area, previously cropped to dry-
land wheat, was used each year. Atrazine (2-chloro-4(ethylamino)-6(isopropylamino)
-s-triazine) was applied for volunteer wheat and weed control before mulch placement'
Soil water content was measured periodically from July until the following May,
when grain sorghum was planted, and during the sorghum growing season. Available
soil water at planting averaged 12.3 and 21.4 cm for the 0- and 12-metric tons/ha
mulch treatments, respectively. The additional water, along with greater infil-
tration and lower evaporation during the growing season, increased grain yields,
which averaged 1,780 and 3,990 kg/ha for the respective treatments. Water-use
efficiency increased from 55.6 kg/ha-cm for no mulch to 115.0 kg/ha-cm'for 12
metric tons mulch/ha.
78:03F-056
A SOIL-WATER-NITROGEN MODEL FOR IRRIGATED CORN ON SANDY SOILS,
Watts, D.G., and Hanks, R.J.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Soil Science Society of America Journal, Vol. 42, No. 3, p 492-499, May-June,
1978. 8 fig, 25 ref, 20 egu, 1 append.
Descriptors: Nitrogen, Nitrates, Leaching, Model studies, Soil-water-plant
relationships, Sweet corn, Diffusion, Convection, Water balance, Irrigation.
A model was developed which describes the net changes of nitrogen amounts due to
transformations and the movement, uptake, and loss of nitrogen from the root
system of irrigated corn (Zea mays L.) grown on sandy soils. A potential
nitrogen uptake function developed from field data is used to determine the
maximum uptake for nonlimiting soil water and nitrogen availability. Actual
uptake is calculated as less than potential when soil water content and/or
mineral nitrogen concentration and distribution limit convective and diffusive
movement of nitrate to the root system. Separate calculations are made for
uptake resulting from each of these two mechanisms. Seasonal nitrogen uptake
was computed within ±15% of measured uptake on field plots where uptake by
above ground plant material ranged from 105 to 218 kg/ha. Computed nitrate
leaching losses compared favorably with losses estimated by multiplying perco-
lation loss determined from a weekly water balance, by measured nitrate concen-
tration at 150 cm depth. Field leaching losses estimated by the water balance-
concentration method ranged from 37 to 154 kg/ha.
78:03F-057
NITROGEN SOURCES FOR HAY PRODUCTION ON FLOODED MEADOWS,
Ludwick, A.E., Rumburg, C.B., and Siemer, E.G.
Colorado State University, Fort Collins, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 3, p 509-512, May-June, 1978.
7 tab, 13 ref.
Descriptors: Nitrogen, Nitrogen compounds, Ammonium compounds, Fertilizers,
Ureas, Nitrates, Denitrification, Hay, Flooding, Volatility.
Three experiments were conducted over a 3-year period to compare various urea
materials and ammonium nitrate as N sources for hay production on flooded meadow
sites. Each experiment was a complete factorial combination of fertilizer N
sources and rates broadcast once in the spring on established forage prior to
flood irrigation. The N sources in these experiments consisted of ammonium
nitrate, urea, sulfur-coated urea, urea ammonium polyphosphate and urea ammonium
sulfate. Hay yields and N uptake were significantly increased by N fertilizer
at each location; there was no significant response in hay yield or N uptake
resulting from residual N in the second season of Experiment 1. Source of N
did not influence hay yields nor N uptake.. The N content of the hay was signifi-
cantly influenced by the N fertilizer rate at two locations and the N source at
one location. In general, hay yields and N uptake increased with increasing
rates of fertilizer N. Fertilizer efficiency was low, at all locations, ranging
134
-------
between 8.5 and 19.6 kg hay/kg N. Fertilizer N recovery was <30% for all
treatments. Both efficiency and recovery of N tended to decrease with increasing
N rates.
78:03F-058
COMPUTER PROGRAMMING SOLID SET SYSTEMS,
Griffin, S.G.
The Toro Company, Riverside, California.
Paper No. 78-2012, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 9 p.
Descriptors: Sprinkler irrigation, Uniformity coefficient, Computer programs,
Water shortage. Testing, Simulation analysis, Nozzles, Water pressure, Design
criteria, Irrigation efficiency.
Solid set sprinkler system uniformity is of great importance in today's
agriculture. A computer program for evaluating sprinkler performance has been
developed. This program has shown to be valuable in product development as well
as providing more accurate information on system operation to the grower in
the field.
78:03F-059
CONTOUR FURROW IRRIGATION WITH LIQUID MANURE USING "MICROTUBING" FOR FLOW CONTROL,
DeTar, W.R.
Pennsylvania State University, University Park, Department of Agricultural
Engineering.
Paper No. 78-2027, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 45 p. 15 fig, 9 tab,
4 ref, 78 equ.
Descriptors: Contour furrows, Furrow irrigation, Fertilizers, Liquid wastes,
Flow control, Irrigation systems, Irrigation, Water management (applied).
The trickle-furrow concept is introduced. The low infiltration rate of dilute
liquid manure makes possible 100 ft lengths of run with only 0.3 gpm/furrow.
Furrows can run 8 hrs/set. Proposed is a solid-set arrangement of 1000 ft of
corrugated plastic tubing laterals descending 5-10% slopes with microtubing
outlets at each furrow. Field experiment yields rate-of-advance curves. A
prediction equation is given for length of run. Friction loss data are
presented. Work is still in progress.
78:03F-060
MANAGEMENT FOR MINIMIZING NITROGEN LEACHING LOSSES ON IRRIGATED SANDY SOILS,
Watts, D., Martin, D., Tscheschke, P., and England, M.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Paper No. 78-2025, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 22 p. 14 fig, 8 ref.
Descriptors: Nutrient removal, Nitrogen, Nitrates, Leaching, Organic matter,
Water management (applied), Nitrogen fixation, Corn (field), Nebraska, Soil
texture.
A model study was made to evaluate nitrogen uptake and the loss of water and
nitrate from the root zone of irrigated corn on sandy soils in Western Nebraska.
Three N sources, two N amounts and a wide range of irrigation applications were
simulated for growing seasons with normal and 75 percent above normal rainfall.
Control of irrigation amounts to minimize percolation and proper selection of
nitrogen amount and source all had a significant effect on nitrate leaching loss.
135
-------
78:03F-061
PEACH TREE RESPONSE TO DRIP APPLICATION OF WATER AND NUTRIENTS,
Chesness, J.L., and Couvillon, G.A.
Georgia University, Athens, Department of Agricultural Engineering.
Paper No. 78-2019, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 19 p. 1 fig, 4
tab, 36 ref.
Descriptors: Irrigation systems, Crop response, Crop production, Peaches, Water
management (applied), Fertilization, Nutrients, Nutrient requirements, Irrigation,
Southeast United States.
Two years of peach tree response to drip irrigation were reported on. Four
treatments involving two water regimens and two water applied fertilizer rates
were investigated. Yield in kg/cm trunk diameter/tree averaged 43 percent
higher for the irrigated treatments. There was no significant differences in
the yield and elemental leaf tissue levels for trees receiving one-half levels
of nutrients applied through the system.
78:03F-062
QUANTIFICATION OF RICE YIELD BENEFITS ATTRIBUTABLE TO IRRIGATION WATER,
Bhuiyan, S.I., and Sumayao, A.
International Rice Research Institute, Los Banos, Laguna, Philippines,
Department of Irrigation and Water Management.
Paper No. 78-2022, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 12 p. 15 fig, 1 tab,
16 ref.
Descriptors: Rice, Irrigation, Water management (applied), Moisture stress,
Crop response, Crop production, Yield equations/ Regression analysis, Management,
Irrigation effects.
An experiment with a split-plot design was conducted at three different locations
to grow LR-36 variety of rice in the dry season when no crop can be grown without
irrigation water in order to quantify rice yield benefits due to irrigation under
farmers' field condition. Five irrigation treatments, representing various
degrees of water stress during the reproductive growth stage of the crop, were
imposed in the main plots and three management package treatments, representing
the average farmer's level, intermediate level and high level use of other
inputs, were imposed in the subplots. High level of management combined with
adequate water produced about 5.1 t/ha, whereas farmer level management under
adequate water yielded 2.9 t/ha. Yield was reduced consistently as stress days
increased. An average of thirty one stress days caused a yield reduction of
1.0 t/ha under the farmer level, management, but an average reduction of about
1.5 t/ha under the two higher level managements. A regression model developed
showed that the location of the experiment had no significant effect on the
yield. The model predicts yield variation due to stress days and level of
management. Management was found to have a much stronger influence on yield
than water stress.
78:03F-063
POTATO AND LETTUCE RESPONSE TO IRRIGATION METHODS AND PRACTICES,
Sammis, T.W., and Hanson, E.G.
New Mexico State University, Las Cruces.
Paper No. 78-2020, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 11 p. 2 fig, 7 tab,
9 ref.
Descriptors: Irrigation practices, Irrigation systems. Surface irrigation,
Subsurface irrigation. Sprinkler irrigation, Potatoes, Lettuce, Irrigation
efficiency, Crop response, Crop production.
Spring potatoes and fall lettuce were irrigated with sprinkler, trickle, sub-
surface, and furrow irrigations for two consecutive years. Results are pre-
sented that pertain to the influence of these methods on crop yield, water-use
efficiency, quality at maturity, and the variability of measurements. The lowest
irrigation ratio for two consecutive years was achieved by trickle and subsurface.
136
-------
Water-use efficiency was indeterminate for the 1975 lettuce cropping year. In
1976, lettuce that was subsurface irrigated resulted in the highest water-use
efficiency. Potatoes subsurface and trickle irrigated resulted in the highest
water-use efficiency in 1975, and those irrigated by subsurface irrigation
resulted in the highest water-use efficiency in 1976.
78:03F-064
ASSESSING TRICKLE EMITTER APPLICATION UNIFORMITY,
Nakayama, F.S., Bucks, D.A., and Clemmens, A.J.
U.S. Water Conservation Laboratory, 4331 East Broadway, Phoenix, Arizona 85040.
Paper No. 78-2017, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 7 p. 6 fig, 2 tab,
4 ref, 14 equ, 2 append.
Descriptors: Irrigation systems, Uniformity coefficient, Water conservation,
Application methods, Irrigation efficiency, Sprinkler irrigation, Statistical
methods, Flow rates, Frequency curves, Irrigation.
A method was developed for showing the uniformity of water application by trickle
emitters based on the emitter's coefficient of variation. The derived design
uniformity coefficient equation for different numbers of emitters per plant
was related to the uniformity coefficient used in sprinkler irrigation. The
interrelationship between the computed design uniformity coefficient, the
manufacturer's coefficient of variation for the emitter, and the number of
emitters per plant can be used as a guide for selecting the number of emitters
per plant. In addition, a field uniformity coefficient and a field emitter
coefficient of variation were related to the fraction of plants adequately
irrigated.
78:03F-065
DRIP IRRIGATION OF ORANGE TREES IN HUMID CLIMATE,
Myers, J.M., and Harrison, D.S.
Florida University, Gainesville, Department of Agricultural Engineering.
Paper No. 78-2018, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 7 p. . 9 tab, 8 ref.
Descriptors: Sprinkler irrigation, Irrigation systems, Oranges, Humid climates,
Fertilization, Citrus fruits. Crop production, Irrigation, Statistical methods,
Florida.
Results of a four-year study of drip and overhead sprinkler irrigation on orange
trees grown in Florida on a sandy soil indicate responses are highly dependent on
rainfall amounts and characteristics. For a year with rainfall 28% below normal
average yields from trees with 2, 4 and 6 emitters/tree were 4.00, 4.24 and 4.83
boxes/tree, respectively. Yields for sprinkler and no irrigation checks were
4.41 and 2.37 boxes/tree. Differences In yield between the three drip irrigation
treatments and the sprinkler check were not significant at the 95% confidence
level, however, all four of these treatments were significantly better than the
no irrigation check. Average yields for quantities of water for drip irrigation
were 4.13, 5.16 and 5.43 boxes/tree for low medium and high amounts, respectively.
The statistical significance of the water quantity results are identical to those
for the emitter density results. Supplemental fertilizer application, through
the drip water distribution system, of 19-0-19 k/ha/year and 38-0-38 k/ha/year
of N-P-K did not appear to influence yields of oranges. Irrigation treatments
did not significantly affect production in years with average or above average
rainfall. Juice content and quality was not influenced by irrigation treatment
or rainfall.
78:03F-066
A SOLAR-POWERED PUMP FOR IRRIGATION,
Alexander, G.H.
Battelle Memorial Institute, Columbus, Ohio, Columbus: Laboratories.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 1-19, February 26-28, 1978. 8 fig.
Descriptors: Pumps, Pumping plants, Irrigation, Energy conversion, Economic
feasibility.
137
-------
A solar-powered irrigation pump designed for the Northwestern Mutual Life
Insurance Company by Battelle Memorial Institute has been in experimental and
developmental operation at Northwestern Mutual's Paloma Ranch near Gila Bend,
Arizona, since April 1977. An objective of this program was to design and
construct a prototype 35- to 50-horsepower solar-energy pumping system to
evaluate its applicability in a working irrigation environment. The range
includes approximately 22,000 irrigated acres; the yearly energy bill for
pumping water is approximately $1.5 million.
78:03F-067
ENERGY AND IRRIGATION,
Oostermeyer, J.S.
Shell Chemical Company, Houston, Texas.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 20-27, February 26-28, 1978.
Descriptors: Energy, Energy conversion, Irrigation, Agriculture, Irrigation
practices, Pesticides, Fertilizers, Nuclear energy, Oil, Natural gas.
This paper reviews the energy situation in the United States and how the energy
shortage is going to affect the national economy, thereby, the irrigated
agriculture. It also suggests the directions of a sound national energy policy
to deal with the situation and recommends better farm management practices to
reduce the cost of energy in irrigated agriculture.
78:03F-068
SOLID STATE CONTROL SYSTEMS FOR IRRIGATION,
Marian, M.B.
Solar Wind Systems, Incorporated, San Rafael, California.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 35-37, February 26-28, 1978.
Descriptors: Irrigation programs, Irrigation, Scheduling, Control systems,
Automatic control. Computer programs, Computer models.
This paper discusses the basic principles of solid state control systems, causes
of failure or malfunction of the systems, customer's responsibilities to insure
proper function, and their applicabilities in irrigation scheduling. Further,
it discusses three basic ways to program an irrigation controller and recommends
the use of removable media such as programming with a mark sense card.
78:03F-069
ELECTRICAL LOAD AND WATER MANAGEMENT,
Heermann, D.F., and Duke, H.R.
Science and Education Administration, Fort Collins, Colorado, United States
Department of Agriculture.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 60-67, February 26-28, 1978. 4 fig, 9 ref.
Descriptors: Load distribution. Electric power demand, Water management (applied)*
Peak loads, Sprinkler irrigation.
The objective of this paper is first, to review the presently used techniques
for retducing peak demands on electrical systems, second, to examine a technique
for improving the water management of center pivot sprinkler systems and, third,
to explore the integration of load management and water management. An analysis
of these aspects led to the conclusion that an integrated load and water manage-
ment control system offers significant cost savings to today's irrigator.
78.-03F-070
CENTER PIVOTS ON SOILS MARGINALLY SUITED FOR IRRIGATION IN MANITOBA, CANADA,
Penkava, F.F.
Manitoba University, Winnipeg, Manitoba, Canada, Department of Agricultural
Engineering.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio>
p 68-75, February 26-28, 1978. 3 fig, 7 ref.
138
-------
Descriptors: Sprinkler irrigation, Irrigation effects, Soil classification,
Productivity, Crop production, Soil erosion, Runoff, Potatoes, Soil physical
properties, Canada.
The Almasippi series soils of Manitoba have poor moisture holding capacity and
high groundwater tables. In spite of those very serious disadvantages irrigated
potato production will likely expand on the Almasippi soils. In order to acquire
more knowledge on the proper use of center pivot irrigation and on the possible
problems and measures for their elimination, a research project was initiated
in the spring of 1977 on two localities on which center pivot units were just
being installed. The following preliminary conclusions were made based on the
research findings: (1) Center pivots, or any other irrigation systems used on
the Almasippi series soils in Manitoba must be carefully designed and operated;
(2) Single applications should not exceed 20 mm; (3) Application intensities
must be carefully balanced with infiltration capacities of the soils and no
credit must be given to surface water detention; (4) In carbonated areas applica-
tion intensity should not exceed 5 mm per hour (0.2 inch/hr); (5) Oversized
center pivot units with high precipitation intensities near the end tower should
not be used; (6) Random subsurface drainage should be used to control the
groundwater levels in the depressions; and (7) Research should continue under
real irrigation conditions.
78:03F-071
APPLICATION OF END GUNS ON CENTER PIVOTS,
Hanson, R.E.
Nelson Irrigation Corporation, Grand Island, Nebraska.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 91-103, February 26-28, 1978. 8 fig.
Descriptors: Sprinkler irrigation, Uniformity coefficient, Distribution patterns,
Drops (fluids), Application equipment. Crop production. Water management (applied),
The main factors probably considered by the pivot irrigator in selecting the use
of end guns are the favorable cost per acre and obtaining the maximum corner
coverage. Use of end guns in combination with corner covering type systems, end
gun :sizes in combination and larger end guns have been more recent adaptations
on center pivots to extend the corner coverage. Many factors affect the corner
coverage obtainable with an end gun. Some of these factors can only be determined
through a complete system design for the conditions. Selection of the end gun
for the system conditions are based primarily on the gun performance, arc setting,
pressure, trajectory angle and nozzle size. Proper application of end guns
generally involves the same field, soil, crop, climatic and water supply condi-
tions that must be considered in center pivot application. In addition to ob-
taining maximum effective corner coverage, other considerations are uniformity
of application, droplet impact conditions and application rate. This paper
discusses the factors affecting these considerations in the use of end guns on
center pivot systems.
78:03F-072
LIMITS OF LOW PRESSURE SPRINKLERS AND SPRAY NOZZLES ON CENTER PIVOT APPLICATIONS,
Gilley, J.R.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 104-115, February 26-28, 1978. 6 fig, 3 tab, 9 ref, 1 equ.
Descriptors: Sprinkler irrigation, Limiting factors, Nozzles, Application
equipment, Uniformity coefficient, Pressure head, Irrigation efficiency, Runoff,
Soil erosion.
Low pressure center pivot irrigation systems offer the potential of applying
irrigation water with significant energy savings. However, lowering the pressure
of center pivot systems may create potential problems of runoff and soil erosion,
uniformity of water application and operation. The future use of low pressure
systems is dependent upon the solutions of these problems. In some cases low
pressure systems should not be used. This paper presents an analysis and
discussion of the effects of lower pressures on center pivot applications.
139
-------
78:03F-073
SCHEDULING OF WATER AND NITROGEN FOR CORN IN THE HUMID MIDWEST,
Vitosh, M.L.
Michigan State University, East Lansing, Crop and Soil Science Department.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 116-123, February 26-28, 1978. 1 fig, 4 tab, 11 ref.
Descriptors: Scheduling, Irrigation, Water management (applied), Sweet corn,
Nitrogen, Fertilization, Humid climates, Michigan.
This study was conducted in Michigan on irrigated sandy soils where irrigation
of corn is a relatively new practice compared to the semi-arid regions. It was
recommended that application rate should not exceed 30% of the water holding
capacity in the effective rooting zone since the optimum soil moisture level
for corn is usually between 50 and 80% of the available water holding capacity.
This will prevent or minimize the leaching of nitrate-nitrogen from the rooting
zone in the event of rain. Adequate moisture must be available at the end of the
growing season to carry the crop to maturity. Further, it was recommended to
apply approximately one-third of the total N requirement for the crop as: (a)
preplant incorporated or pre-emergence with a herbicide; (b) one-third sidedress
or pre-emergence if the first third was applied preplant; and (c) one-third through
the irrigation system which should be applied prior to pollination.
78:03F-074
THE ROLE OF SPRINKLER IRRIGATION IN PRODUCING SPECIALTY CROPS,
Patterson, C.
Patterson Farms, China Grove, North Carolina.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 124-125, February 26-28, 1978.
Descriptors: Sprinkler irrigation, Frost protection, Freezing, Tomatoes,
Strawberries, North Carolina.
The benefits of using a solid set sprinkler irrigation system for frost and freeze
protection of tomato and strawberry production in North Carolina were discussed.
78:03F-075
THE USE OF OVERTREE IRRIGATION FOR CROP COOLING AND FROST AND FREEZE PROTECTION
ON APPLES,
Unrath,- C.R., and Sneed, R.E.
North Carolina State University, Raleigh, Department of Horticultural Science.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 131-134, February 26-28, 1978.
Descriptors: Sprinkler irrigation, Cooling, Freezing, Frost protection, Apples,
Peaches, Fruit crops, North Carolina.
Overtree irrigation for apple orchard cooling has proven to be an effective method
of microclimate modification resulting in markedly improved fruit quality and
greater grower returns. The experimental results showed that the evaporative
cooling resulted in increased fruit coloration of red varieties' apples and in-
creased sugar content, fruit size and reduced incidence of cork spot and bitter
pit. The application rates of 0.16 in/hr to 0.18 in/hr were found to be effective
and to provide higher water use efficiency than lower application rates. Over-
tree irrigation for frost and freeze protection was also evaluated and application
rate between 0.16 in/hr to O.18 in/hr was recommended for severity of freeze
conditions.
78:03F-076
OPTIMIZING TRAVELING SPRINKLER SYSTEM PERFORMANCE,
Rupar, B.
Nelson Irrigation Corporation, Walla Walla, Washington.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 152-159, February 26-28, 1978. 5 fig, 1 tab, 2 equ.
140
-------
Descriptors: Sprinkler irrigation, Uniformity coefficient, Application equipment,
Pressure head, Distribution pattern, wind velocity.
Many factors affect the proper performance of traveling sprinkler irrigation
systems. Among the most important considerations are uniformity of application,
water droplet conditions and the application rate of the system. Test data, as
well as actual field experience, confirms that a high degree of uniformity is
achievable with a traveler, as long as proper lane spacing arid travel direction
are utilized, as well as proper arc setting the pressure. Acceptable droplet
conditions can be achieved only through the use of adequate pressure and proper
selection of trajectory angle for a given nozzle size. Application rates for
travelers are sufficiently low to make them adaptable for most soil conditions.
78:03F-077
INTRODUCTION TO IRRIGATION EFFICIENCY AND SCHEDULING,
Aljibury, F.K.
California University, Parlier, Cooperative Extension.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 160-161, February 26-28, 1978. 1 tab.
Descriptors: Irrigation efficiency, Scheduling, Water shortage, Sprinkler
irrigation, Consumptive use, Agriculture.
The subject of rational use of water is of vital interest. The allocation of
existing supplies of water is becoming difficult and controversial. Irrigation
efficiency and scheduling concepts play important roles in this context.
78:03F-078
FACTORS INFLUENCING SYSTEM SELECTION IN HUMID REGIONS,
Curtis, L.M.
Auburn University, Auburn, Alabama, Alabama Cooperative Extension Service.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 126-130, February 26-28, 1978. 5 fig.
Descriptors: Irrigation, Humid areas. Humid climates. Southeast United States,
Irrigation systems, Sprinkler irrigation.
Factors and difficulties that should be evaluated in considering cable tow and
center pivot irrigation systems of 'farms in the Southeast United States were
discussed. The following factors have been analyzed: (1) water supply; (2)
topography and surface characteristics; (3) crops grown and rotation schemes;
and (4) economic considerations. It was concluded that the factors influencing
system selection in the Southeast are numerous. The less favorable factors
may slow or prohibit development of irrigation in some areas. However, continued
expansion of irrigated cropland appears likely as farmers incorporate irrigation
as a production or management tool in their overall farming operation.
78:03F-079
SOCIETAL ATTITUDES AND RESULTANT POLICIES CALL FOR WATER CONSERVATION,
Hagan, R.M.
California University, Davis, Department of Land, Air and Water Resources.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 162-179, February 26-28, 1978.
Descriptors: Water conservation, Social aspects, Social impact, Social
participation, Water policy, Agriculture, Irrigation practices. Irrigation
efficiency, Evapotranspiration, California.
The water situation and, to some extent, societal attitudes have changed
dramatically in California within the past few months. This paper briefly touches
on a number of aspects in order to provide a sample of the kinds of thoughts
being expressed about irrigation agriculture, especially by environmental
leaders. Several points are covered in some detail. Hopefully, these comments
will provide a useful indication of what some vocal elements in today's society
are saying which bear on agricultural water conservation and on the irrigation
industry.
141
-------
78:03F-080
WATER EFFICIENCY WITH DEFICIT AND SUBOPTIMAL IRRIGATION,
Aljibury, F.K./ Gerdts, M., and Beutel, J.
California University, Parlier, Cooperative Extension.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 180-182, February 26-28, 1978. 3 tab.
Descriptors: Cultural control, Water shortage, Water conservation, Irrigation,
Furrow irrigation, Fruit crops, Water management (applied), Irrigation systems,
Irrigation efficiency, California.
Irrigation is considered one of the most important cultural practices in the arid
and semi-arid irrigated areas of the world. The increasing demand for water and
its limited supplies requires maximum efficiency in its use for irrigation. To
achieve this end, many water specialists and plant scientists have been conducting
studies to determine the effect of deficit irrigation on the production "of food
and fibrous crops. The objectives of such experiments are to maximize production
under conditions of drought or limited water supplies. The authors concluded
from their experimental results that the effect of deficit irrigation by furrow
irrigation on the early growth of the plum trees was not significant. The
deficit irrigation did not cause unusual leaf abscission or premature fruit drop.
Total production was not affected but water savings was significant. The effect
of deficit water treatments in the drip irrigated plots, on the soil water
potential and deep moisture extraction was found to be very evident. These
irrigations did not effect the number of fruits per tree and bud initiation of
future seasons significantly but produced fruits of smaller size.
78:03F-081
COMPARATIVE EFFICIENCY OF IRRIGATION SYSTEMS,
Shearer, M.N.
Oregon State University, Corvallis.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 183-188, February 26-28, 1978. 4 fig, 2 tab.
Descriptors: Irrigation efficiency, Irrigation systems, Uniformity coefficient,
Sprinkler irrigation, Surface irrigation, Seepage, Runoff, Evaporation.
The purpose of this paper is to compare efficiencies obtainable with various
irrigation systems having reasonably good designs. Also, several concepts of
field irrigation efficiency have been discussed.
78:03F-082
IRRIGATION EFFICIENCY IN SCHEDULING,
Tribe, G.
Cornell Pump Company, Portland, Oregon.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 189-191, February 26-28, 1978.
Descriptors: Pumps, Pumping plants, Pump testing, Efficiencies, Design criteria.
Testing and experimentation have proven that a pump's ability to convert rotating
kinetic energy to hydraulic pressure energy is predictable. This energy conversion
efficiency can be improved by the application of proven engineering fundamentals.
This paper discusses the need for improving pump efficiency and the factors which
must be considered for improved pump design and to reduce the cost of ownership.
78s03F-083
AUTOMATION OF SURFACE IRRIGATION,
Eisenhauer, D.E., and Fischbach, P.E.
Nebraska University, Clay Center, South Central Station.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 196-205, February 26-28, 1978. 1 fig, 4 tab, 7 ref.
Descriptors: Surface irrigation, Automation control, Irrigation efficiency,
Irrigation systems, Cost comparisons, Nebraska.
142
-------
Efficient and low labor irrigation systems appear to be the way of the future.
Automation of conventional gated pipe systems is a good way of improving
efficiency and yet holding down labor requirements. The main additional com-
ponent of the automatic system is the automatic valve. One such valve is on
the market now and another will be available soon. Design of automatic systems
involves properly sizing pipeline and other components, using normal engineering
criteria, plus designing for the proper field length and furrow stream size.
Annual costs of automatic gated pipe is higher than conventional gated pipe
systems, but recent trends in automatic sprinkler systems suggest that farmers
are willing to invest the extra capital to reduce labor demands.
78:03F-084
PRACTICAL SURFACE IRRIGATION,
Gosling, R.
West Side Pump Company, Dos Palos, California.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 206-208, February 26-28, 1978.
Descriptors: Surface irrigation, Sprinkler irrigation, Irrigation systems,
Automation, Cost comparisons, Flexibility, California.
This paper discusses and makes a comparative analysis of gated pipe surface
irrigation systems with respect to other systems.
78:03F-085
MEASURING EFFICIENCY OF SURFACE IRRIGATION SYSTEMS,
Robinson, S.C.
Bennett & Bennett Irrigation Pipe Company, Hanford, California.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 209-212, February 26-28, 1978.
Descriptors: Surface irrigation, Irrigation efficiency, Application methods,
Application equipment, Return flow, Irrigation systems, Measurement, Border
irrigation, Furrow irrigation, Sprinkler irrigation.
The reasons behind the concept of irrigation efficiency, the definition of
application efficiency, and the various components of efficiency measurement of
surface irrigation systems were discussed. Moreover, the rules of thumb were
outlined which could be used in field applications to attain high application
efficiency of surface irrigation systems.
78:03F-086
SOLAR CELL IRRIGATION,
Fischbach, P.E., and Matlin, R.W.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
P 213-217, February 26-28, 1978. 1 fig, 2 tab.
Descriptors: Irrigation, Energy, Energy conversion, Irrigation systems, Surface
irrigation, Automation, Computer programs, Irrigation programs, Nebraska,
Application equipment.
In the first project of its kind, the largest solar cell-powered crop irrigation
system on earth has been constructed on the University of Nebraska field
laboratory in Mead, Nebraska. Success of the experimental irrigation system could
demonstrate an alternate source of energy for irrigation. A discussion about the
photovoltaic solar cells used in the project, how they converted the solar energy
to electrical energy and how the 80 acre-irrigation project was run and managed
by the system were discussed.
78:03F-087
EVALUATION CRITERIA FOR TRICKLE IRRIGATION EMISSION DEVICES,
Solomon, K.
Rain Bird Technical Services, Logan, Utah.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 218-225, February 26-28, 1978. 4 ref.
143
-------
Descriptors: Irrigation, Irrigation systems, Trickling filters, Clogging, Pressure
head, Variability, Costs, Risks.
The emission device is sometimes referred to as the heart of a trickle irrigation
system. It is important to compare carefully the different types of emission
devices available in order to choose wisely from among possible alternatives.
This paper suggested and discussed some of the factors to be considered when
judging and comparing emission devices. The author suggested that the following
seven fundamental factors should be examined to select a particular emission
device to use in a system: (1) General suitability; (2) Pressure-flow relation-
ships; (3) Manufacturing variability; (4) Flow rate sensitivity to water tempera-
ture; (5) Sensitivity to clogging; (6) Cost and (7) Risk. Some of these can be
considered engineering performance factors, and hence can be measured and
evaluated only subjectively.
78:03F-088
TRICKLE DESIGN FOR MIDWEST CONDITIONS,
Gamble, J.
Farm Bureau Services, Incorporated, Hart, Michigan.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 226-230, February 26-28, 1978.
Descriptors: Irrigation, Irrigation systems, Irrigation design, Irrigation
operation and maintenance, Clogging, Pipelines, Water shortage, Water conservation.
This paper discussed trickle irrigation design concepts, water resources used
for this system in the midwest United States, and installation and operation
criteria for such a system. Current problems facing the users and/or the
installer of the system were also discussed.
78:03F-089
TRICKLE IRRIGATION IN HUMID ZONES,
Braud, H.J.
Louisiana State University, Baton Rouge, Departmen-t of Agricultural Engineering.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 231-238, February 26-28, 1978. 2 fig, 2 tab, 6 ref.
Descriptors: Irrigation systems, Irrigation, Irrigation design, Humid areas,
Louisiana, Productivity, Citrus fruits. Sugarcane.
The need for irrigation in a humid area is specific to the particular crop-soil-
climate. Not all crops respond to irrigation: Citrus does, but not sugarcane
in Louisiana. Work group meetings of scientists interested or involved in
trickle irrigation were held last year to define the most important problems of
trickle irrigation. A regional research project draft was written, "Trickle
Irrigation in Humid Regions," with the following objectives: 1) To determine
water requirements and water management techniques; 2). To develop best procedures
for applying N, P and K; 3) To determine causes of clogging in humid regions and
develop methods to minimize it; 4) To optimize crop management practices; 5) To
examine water and nutrient flow patterns and related root development; 6) To
examine the costs, returns and profitability of trickle irrigation. Research on
trickle is underway or planned at 17 state agricultural experiment stations and
United States Department of Agriculture, Agricultural Research Service research
stations in Louisiana.
78:03F-090
BACTERIAL CLOGGING IN LOW PRESSURE IRRIGATION SYSTEMS,
Ford, H.W.
Florida University, Lake Alfred, Institute of Food and Agricultural Sciences.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 239-244, February 26-28, 1978. 2 fig, 7 ref.
Descriptors: Irrigation systems, Low-flow augmentation, Clogging, Irrigation,
Bacteria, Slime.
144
-------
Bacterial slimes are the fundamental cause of most clogging problems. There are
no types of low pressure irrigation systems immune to slime clogging. Chlorine,
when used in combination with suitable filtration, will control most of the
slimes and associated agents that clog irrigation emitters. Chlorine, like
other pesticides, requires a special use label in order to be used in drip
irrigation systems.
78:03F-091
IA SPRINKLER TEST STANDARDS,
Bruce, D.A.
Product Design & Systems Engineering, Ag-Turf Division, Johns-Manville Sales
Corporation, Fresno, California.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 282-289, February 26-28, 1978. 2 tab.
Descriptors: Sprinkler irrigation, Testing procedures. Standards, Testing,
Performance, Irrigation, Evaluation.
After many years of discussion, rejection and frustration, the irrigation industry
is on the threshold of adopting a uniform method of testing sprinklers, collecting
test data and reporting product performance. This paper outlives the sprinkler
test procedure developed by a working committee formed by The Irrigation
Association. The IA is attempting to issue a joint standard with the American
Society of Agricultural Engineers.
78:03F-092
A NOTE ON THE ECONOMIC SIGNIFICANCE OF UNIFORM WATER APPLICATION,
Seginer, I.
Technion, Haifa, Israel, Department of Agricultural Engineering.
Irrigation Science, Vol. 1, No. 1, August, 1978, p 19-25. 3 fig, 7 ref, 23 equ.
Descriptors: Water distribution (applied), Crop production, Water costs,
Optimization, Economics, Distribution patterns, Sprinkler irrigation, Yield
equations.
It was shown how a yield vs water application diagram, with uniformity of water-
distribution and price of water as parameters, can be used to determine the
optimum water application and the expected income for a certain crop. The
diagram can further be used to explore the possible outcome of changing water
uniformity and/or price. The diagram was based on simplified forms of the
yield and water-distribution functions.
78:03F-093
ANALYSIS OF TRICKLE IRRIGATION WITH APPLICATION TO DESIGN PROBLEMS,
Bresler, E.
Institute of Soils and Water, Agricultural Research Organization, The Volcani
Center, Bet Dagan, Israel, Division of Soil Physics.
Irrigation Science, Vol. 1, No. 1, August, 1978, p 3-17. 6 fig, 1 tab, 18 ref,
19 equ.
Descriptors: Irrigation design, Water conservation, Design, Flow rates,
Infiltration, Hydraulic conductivity, Unsaturated flow.
An existing numerical solution to nonsteady state infiltration was used to
quantify the effect of soil hydraulic properties and trickle discharge rates
on emitter spacing. The results of the analysis suggested the possibility of
controlling the wetted volume of a soil by regulating the emitter discharge
according to soil properties. The surface distribution of a transformed soil
water content (or pressure) function was derived from a linearized solution
to steady infiltration. The analysis of steady and nonsteady infiltration
was employed to estimate the spacing between emitters as a function of discharge
and water pressure conditions between emitters using hydraulic soil data.
Hydraulic conductivity parameters were given for 17 different soils which were
used for design purposes. Theoretical analysis of soil water was combined with
hydraulic principles to derive lateral diameter and length for engineering
design requirements.
145
-------
78:03F-094
CENTER PIVOT IRRIGATION IN THE COLUMBIA BASIN OF WASHINGTON AND OREGON: DYNAMICS
AND IMPLICATIONS,
Muckleston, K.W., and Highsmith, R.M.
Oregon State University, Corvallis, Department of Geography.
Water Resources Bulletin, Vol. 14, No. 5, p 1121-1128, October, 1978. 1 fig,
13 ref.
(See 78:06A-007)
78:03F-095
METHODOLOGY AND EMPIRICAL ESTIMATES OF THE RESPONSE FUNCTION OF SORGHUM TO IRRIGATION
AND SOIL MOISTURE,
Bielorai, H., and Yaron, D.
Institute of Soils and Water, The Volcani Center, Bet-Dagan, Israel, Institute of
Agricultural Research.
Water Resources Bulletin, Vol. 14, No. 4, p 966-977, August, 1978. 3 tab, 4 fig,
17 ref.
Descriptors: *Methodology, *Irrigation, *Soil moisture, *Sorghum, *Crop response,
Estimating, Equations, Systems analysis, Response function, Critical days.
Presented is a methodology for the estimation of response functions of crops to
irrigation and soil moisture. A systems analysis framework is applied to describe
the relationships involved. Two subsystems are distinguished, with the first one
involving the relationship between irrigation decision variables and soil state
variables, and the second involving the relation between soil state variables and
crop yield. A method for tracing and predicting soil moisture profile variations
over time and depth is presented, and empirical estimates of the response function
of grain sorghum to soil moisture are derived. In the specification of the response
function the concept of "critical days" is applied with a "critical day" being
defined as one where the soil moisture is depleted below a certain critical level.
The paper provides empirical evidence for the usefulness of the approach.
78:03F-096
ECONOMIC AND AGRONOMIC EFFECTS OF HIGH IRRIGATION LEVELS ON ALFALFA AND BARLEY,
Delaney, R.H., Jacobs, J.J., Borrelli, J., Clark, R.T., and Hedstrom, W.E.
Wyoming University, Laramie, Water Resources Research Institute.
Water Resources Series No. 68, January, 1978, 78 p. 7 fig, 27 tab, 46 ref.
Descriptors: Irrigation effects, *Agronomic crops, *Drainage, *Agricultural
econcwd.cs, *Irrigation practices, Income, Labor savings, Profit, Surface
irrigation, Crop response, Irrigation efficiency, Leaching, Water injury,
Alfalfa, Barley, Feed barley, Malt barley, Overirrigation, Excess water.
Five water levels were used on alfalfa, feed barley, and malt barley. Treatments
2, 4 and 5 were irrigated with quantities of water sufficient to bring the soil
to field capacity (FC) from 50% of the available moisture (AM), twice this
quantity and four times this quantity, respectively. Treatments 1 and 3 were
irrigated to FC when 90 and 10% respectively, of the AM was depleted. The
highest irrigation level on alfalfa yielded an average of 2 mt/ha/yr less than
level 1 over the 3 year study and 1-1/2 mt/ha/yr less than level 2, which was
the check treatment. The phosphorus content of the forage was reduced -by the
two driest irrigation levels and could require P supplementation when fed to
some classes of livestock. The yield of feed barley for the highest irrigation
level was reduced 18% when compared to the driest treatment. The average yield
of malt barley for the 2 years was reduced 22% by irrigation level 5 compared to
irrigation level 1. An economic analysis of the plot yield data showed that
irrigation practice No. 1 provided the largest return to management and land.
These results suggest that irrigators might be able to reduce the quantity of
water used and increase yields as well. An analysis of the yield data for crops,
both with and without irrigation scheduling fIS), showed that yields were
generally higher when a crop was under IS. An economic analysis of the yield
increase for alfalfa and barley indicated that the increased yield would more
than pay for the cost of the IS service. For the given physical situation and
irrigation practices similar to those used in water level 3, the drainage system
would cost $86/ha/yr, for water level 4-$272/ha/yr, and for water level 5-
$1038/ha/yr.
146
-------
78:03F-097
PERFORMANCE OF CENTER-PIVOT SPRINKLER IRRIGATION SYSTEMS OPERATING AT REDUCED
PRESSURES /
All, S.M.A., and Barefoot, A.D.
Oklahoir* State University, Stillwater, Department of Agricultural Encrineerincr
Paper N.,. 78-2005, Presented at the 1978 Summer Meeting of the American Society
14 re" tUral Engineers, June 27-30, 1978, Logan, Utah, 19 p. 4 fig, 4 tab,
Descriptors: Sprinkler irrigation, Irrigation systems, Performance, Water
pressure, Low flow, Uniformity coefficient, Distribution patterns, Evaporation
J- 1T3T iCfcl tlOTl *
Spray distribution obtained from a single stationary sprinkler head was utilized
to determine the effects of reduced operating pressure on evaporation loss,
uniformity of application, sprinkler spacing, and application rate of a center-
pivot sprinkler irrigation system. Results indicated that at reduced pressure
the sprinkler performances were satisfactory.
78:03F-098
"CORNER PIVOT" AN EFFECTIVE CORNER WATERING SYSTEM,
Callies, R.E.
Lindsay Manufacturing Company, Lindsay, Nebraska.
Paper No. 78-2006, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p.
Descriptors: Sprinkler irrigation, Irrigated land, Irrigation efficiency,
Irrigation systems, Design, Performance, Distribution, Distribution systems,
Irrigation.
The "Corner Pivot" system incorporates the use of a long span single tower center
pivot irrigation machine which is attached to and pivots about the outer most
tower of a conventional center pivot irrigation machine. This attachment is used
to extend the reach of the standard machine for the purpose of watering the
corners or irregularly shaped areas along the perimeter of the field which could
not normally be reached by a conventional center pivot machine.
78:03F-099
MATHEMATICAL MODELS AND BORDER IRRIGATION DESIGN,
Fangmeier, D.D., and Strelkoff, T.
Arizona University, Tucson, Department of Soil, Water and Engineering.
Paper No. 78-2007, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 11 p. 11 fig, 4 tab,
6 ref, 19 equ.
Descriptors: Border irrigation, Irrigation design, Mathematical models,
Evaluation, Runoff, Design criteria, Infiltration rates, Recession curves, Time
lag, Irrigation efficiency.
A mathematical model of flow in irrigation borders assuming zero inertia was used
to evaluate U.S. Soil Conservation Service design criteria for sloping borders
with runoff and to demonstrate model capabilities. Model results indicated that
the Soil Conservation Service design criteria are reasonable.
78:03F-100
BORDER-STRIP IRRIGATION DESIGN—PRACTICAL APPROACH FROM A THEORETICAL BASIS,
Merriam, J.L.
California Polytechnic State University, San Luis Obispo, Department of Agricultural
Engineering.
Paper No. 78-2008, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 14 p. 14 fig, 1 tab,
2 ref, 3 equ.
Descriptors: Irrigation design, Border irrigation, Surface irrigation, Graphical
methods, Recession curves. Flow rates, Irrigation efficiency, Moisture deficit,
Time lag, Infiltration.
147
-------
A graphical procedure was developed for designing border-strip irrigation
systems. It is based on the principle that the shape of the recession curve
is relatively unchanging for any specific field, and therefore, it is the
controlling key condition for design or operation. Conditions modifiable by
the designer or operator to obtain high efficiency are: (1) the stream size
that controls the rate of advance; (2) the Management Allowed Deficiency of
soil moisture at the time of irrigation; (3) the length of the strip; and
(4) the distance down the strip at which flow is cut off.
78:03F-101
RAPIDLY OBTAINING OPTIMAL IRRIGATION SYSTEM DESIGNS,
Busch, J.R., Galinato, G.D., Brockway, C.E., and Steinbach, G.E.
Idaho University, Aberdeen.
Paper No. 78-2009, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 16 p. 6 fig, 8 ref.
Descriptors: Irrigation design, Irrigation systems, Irrigation, Optimization,
Computer programs, Computer models, Cost allocation, Costs, Dynamic programming,
Linear programming.
A methodology was developed and tested that will allow irrigation planners
to obtain optimal system designs. Computer routines were used to obtain costs
of individual system components. The optimization procedures produce least
cost designs subject to specified constraints and these constraints can easily
be changed to allow rapid evaluation of alternatives.
78:'03P-102
COMPUTER MODEL FOR CENTER PIVOT SPRINKLER DESIGN,
Kelso, G.L., and Jarrett, A.R.
Pennsylvania State University, University Park, Department of Agricultural
Engineering.
Paper No. 78-2003, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 19 p. 12 fig, 6 tab,
7 ref, 42 equ.
Descriptors: Sprinkler irrigation, Computer models, Computer programs, Irrigation
systems, Flow rates, Uniformity coefficient, Irrigation design, Irrigation.
A computer aided center pivot design program was presented. The program selected
specific sprinklers and nozzles from input parameters of flow rate to the pivot,
system length, sprinkler spacing and desirability of an endgun. The program also
computed a uniformity coefficient for the system based on the sprinklers and
nozzles selected.
78:03F-103
THE USE OF COMPUTERS TO NOZZLE CENTER PIVOT SYSTEMS,
Morgan, R.M.
The Toro Company, Riverside, California 92504.
Paper No. 78-2002, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 8 p.
Descriptors: Sprinkler irrigation, Distribution patterns, Computer programs,
Distribution, Nozzles, Irrigation systems. Water distribution (applied). Irrigation.
The practice of irrigation by sprinkler head distribution on center pivot machines
has been a system of application crops for nearly twenty years. Many types of
heads and spacings have been used with a goal toward achieving more even distribution'
The art of computer-use to predetermine distribution uniformity was discussed.
78:03F-104
DETERMINING CENTER-PIVOT SPRINKLER UNIFORMITIES,
Ring, L., and Heermann, D.F.
Agriculture Center, Lethbridge, Alberta T1J 4C7, Alberta Agriculture.
Paper No. 78-2001, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p. 3 fig, 6 tab,
12 ref, 4 egu.
148
-------
Descriptors: Sprinkler irrigation, Uniformity coefficient, Irrigation efficiency,
Distribution, Distribution patterns, Irrigation design, Evaluation, Irrigation.
Catch can evaluations were conducted and the water application and uniformity were
calculated for different can spacings and number of rows. Results were compared
to each other and to a theoretical application pattern. A recommended procedure
for the field evaluation of center-pivot systems was suggested.
78:03F-105
VARIABILITY OF SPRINKLER COEFFICIENT OF UNIFORMITY TEST RESULTS,
Solomon, K.
RainBird Technical Services, Logan, Utah.
Paper No. 78-2010, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 10 p. 2 fig, 2 tab,
4 ref.
Descriptors: Sprinkler irrigation, Uniformity coefficient. Irrigation efficiency,
Statistical methods, Regression analysis. Variability.
Sprinkler coefficient of uniformity (UC) test results were analyzed and found to
vary significantly, even under similar test conditions. The amount of anticipated
variation in measured UC values was correlated with the UC value itself. Factors
influencing this variation were discussed.
78:03F-106
REUSE PITS: CHEAPEST WATER ON THE FARM,
White, J.G.
Denver, Colorado.
Irrigation Age, Vol. 13, No. 3, p 58, 62, November-December, 1978. 2 fig.
Descriptors: Tailwater, Water conservation, Irrigation efficiency, Irrigation,
Crop production. Irrigation practices, Nebraska, Agricultural runoff.
This article describes the benefits of using tailwater pits as experienced by
farmers in Nebraska. It was found that the pumping cost was reduced by one-
fourth compared with what it costs to pump from the deep wells, reduced the
time and labor, and reduced the amount of deep-well water use by 20%. It was also
estimated that the gravity irrigation efficiency was increased by almost 15%.
78:03F-107
A PROGRAM TO PROMOTE IRRIGATION CONSERVATION IN IDAHO,
Hammond, J.
State of Idaho, Statehouse, Boise, Department of Water Resources.
Pacific Northwest Regional Commission, March, 1978. 43 p, 6 fig, 12 ref.
Descriptors: Water conservation, Irrigation, Programs, Idaho, Water management
(applied), Water law, Water costs, Social aspects, Legal aspects, Water delivery.
This study investigated the economic, social, legal and institutional factors
affecting irrigation efficiency and sought incentives for promoting irrigation
water conservation. This report presents the results of the study and outlines
alternatives for formulating a comprehensive irrigation conservation program.
Specifically, it discusses the promotion of irrigation water conservation, attitudes
and incentives involved in such conservation, water conservation aspects of Idaho
laws, and evaluates three alternative programs for pomoting irrigation water
conservation.
78:03F-108
CONSERVATION AND CONVENTIONAL SYSTEMS FOR CONTINUOUS PRODUCTION OF CORN,
Erbach, D.C., Lovely, W.G., and Ayres, G.E.
Iowa State University, Ames, Department of Agricultural Engineering.
Paper No. 78-2517, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 9 p. 4 fig, 9 tab, 22 ref.
149
-------
Descriptors: Till, Soil management, Conservation, Crop production, Corn (field),
Economics, Weed control, Iowa.
Seven tillage systems were evaluated for continuous production of corn in Central
Iowa on a soil from the Clarion-Nicollet-Webster Soil Association. Comparative
week control, stand establishment, surface plant residue, soil nutrient profile,
yield, and economic results were discussed.
78:03F-109
WATER BALANCE IN IRRIGATED SOILS,
Botzan, M., and Merculiev, O.
Academy of Agriculture and Forest Sciences, Bucharest, Romania.
ICID Bulletin, Vol. 27, No. 2, p 23-29, 35, July, 1978. 26 ref.
Descriptors: Water balance. Irrigation design, Irrigation programs, Consumptive
use, Soil-water-plant relationships. Leaching, Evapotranspiration, Irrigation.
The paper presented the results obtained by land experimental research works
carried out in different pedoclimatic zones of Romania (temperate zone) between
1945-1947 and continuously since 1951. The water balance elements (initial
reserve, final reserve, winter and summer precipitations, groundwater supply, soil
water consumption on different calculated probabilities on crops and pedoclimatic
zones, the water application and the irrigation rates during the vegetation and
supply periods) were quantitatively characterized. Interrelationships of water
consumption with the type of crop and pedoclimatic zone, soil humidity, air
temperature, and crop yield were established. These correlations allowed for
establishing an indirect water-consumption calculation method. For the irriga-
tion project designing model, the basic elements and the limitative conditions
were established. Both the irrigation as required and irrigation by rotation
were analyzed for the water application forecast and programming. Also, the basic
participating elements of the model in the prognosis stage were established
together with the limitative conditions which determine the water application
program in the row for plots irrigated in a single rotation.
78:03F-110
LATERALLY CONFINED FLOW FROM A POINT SOURCE AT THE SURFACE OF AN INHOMOGENEOUS
SOIL COLUMN,
Merrill, S.D., Raats, P.A.C., and Dirksen, C.
Northern Great Plains Research Center, P.O. Box 459, Mandan, North Dakota 58554.
Soil Science Society of America Journal, Vol. 42, No. 6, p 851-857, November-
December, 1978. 8 fig, 18 ref, 22 equ.
Descriptors: Confined water, Steady flow, Infiltration, Irrigation, Hydraulic
conductivity, Irrigation design, Distribution, Pressure head, Water conservation.
Solution of a linearized flow equation for steady, axisymmetric, laterally
confined infiltration from a point source located at the soil surface was com-
pared with pressure head patterns measured in an undisturbed column of sandy
loam. The geometry approximated an array of trickle irrigation emitters. The
hydraulic conductivity could be represented as an exponential function of both
the pressure head and the depth in the column. This implied that steady, multi-
dimensional flow in the column could be described by a linear flow equation.
Measured and predicted distributions of pressure head agreed most closely at an
application rate of 0.5 cm/day. Increase in the size of a saturated zone about
the point source at application rates higher than 0.5 cm/day caused isolines
of pressure head to be distorted from the predicted shape. Flow patterns for
homogeneous and heterogeneous soil were compared. Measured distributions of
pressure heads under intermittent trickle application were compared with steady
infiltration patterns. It was concluded that a steady-flow solution will give
an approximate prediction of intermittent pressure head patterns for continuously
repeated application cycles over part of the flow region and during part of the
time.
78:03F-111
WATER BALANCE OF FLOODED RICE PADDIES,
Brown, K.W., Turner, F.T., Thomas, J.C., Deuel, L.E., and Keener, M.E.
150
-------
Texas A & M University, College Station, Department of Soil and Crop Sciences.
Agricultural Water Management, Vol. 1, No. 3, p 277-291, November, 1978. 10 fig,
3 tab, 8 ref.
(See 78:021-037)
78:03F-112
REMOTE SENSING FOR AGRICULTURAL WATER MANAGEMENT AND CROP YIELD PREDICTION,
Idso, S.B., Jackson, R.D., and Reginato, R.J.
United States Water Conservation Laboratory, Phoenix, Arizona.
Agricultural Water Management, Vol. 1, No. 4, p 299-310, December, 1978. 5 fig,
32 ref, 5 equ.
Descriptors: Remote sensing, Water management (applied), Crop production,
Scheduling, Irrigation, Albedo, Soil moisture, Evaporation, Reviews.
This paper reviewed the research conducted at the U.S. Water Conservation
Laboratory, Phoenix, Arizona over the past several years relative to agricultural
application of remote sensing. In addition, new data were presented. The
subjects treated were soil moisture, evaporation, irrigation scheduling, and
crop yield estimation. The analyses indicated that we have the technology at
hand to successfully integrate remote sensing techniques into agricultural
operations designed to enhance production via intelligent water management.
78:03F-113
BEST USE OF CROP RESIDUES,
Fenster, C.R., Follett, R.H., and Williamson., E.J.
Nebraska University, Lincoln, Department of Agronomy.
Crops and Soils Magazine, Vol. 30, No. 9, p 10-13, August-September, 1978.
3 fig, 2 tab.
Descriptors: Feeds, Crops, Organic matter, Soil erosion, Energy.
This paper looks at the present and some potential uses of crop residues.
It concluded that the best use of crop residues depends on the crop, the soil,
the location of the place where the particular crop and soil exist, and a
number of other problems directly and remotely related to agriculture.
78:03F-114
CHEMICAL INJECTION POPULAR IN NORTHWEST,
Henry, C.
Irrigation Age, Northwest/Pacific Editor.
Irrigation Age, Vol. 13, No. 3,'p 46-47, November-December, 1978. 3 fig.
Descriptors: Irrigation, Fertilizers, Fertilization, Chemicals, Sprinkler
irrigation, Application methods, Application equipment, Injection.
This article reports and discusses the methods and benefits of applying liquid
chemicals and fertilizers with irrigation water.
78:03F-115
ELECTRONIC TIMERS FOR AUTOMATED SURFACE IRRIGATION SYSTEMS,
Fisher, H.D., Humpherys, A.S., and Worstell, R.V.
Snake River Conservation Research Center, Kimberly, Idaho, United States
Department of Agriculture.
Paper No. 78-2544, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 7 p. 3 fig, 5 ref.
Descriptors: Surface irrigation, Automatic control, Control systems, Automation,
Timing, Electronic equipment. Instrumentation, Furrow irrigation, Irrigation
systems.
Electronic timers were developed to replace alarm clocks and mechanical timers
for semirutomated irrigation structures and valves. Timer-controllers including
151
-------
a micro-processor unit were designed for a field tested with automatic cutback,
buried lateral and multiset furrow irrigation systems.
78:03P-116
VOLUMETRIC CONTROL FOR IRRIGATION AUTOMATION,
Duke, H.R., Payne, M.L. , and Kincaid, D.C.
Agricultural Research, Science and Education Administration, United States
Department of Agriculture.
Paper No. 78-2545, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 8 p. 3 fig, 4 ref.
Descriptors: Surface irrigation, Automatic control, Control systems, Automation,
Electronic equipment, Instrumentation, Irrigation programs, Irrigation systems.
A digital electronic controller was developed for use in surface irrigation
automation. This controller has full random-multiplexing capabilities and is
capable of integrating flow rates as measured through a nonlinear open channel
flow measurement device.
78:03F-117
UTILIZATION OF A PORTABLE SOLID STATE FURROW IRRIGATION VALVE CONTROLLER,
Edling, R.J., Duke, H.R. , and Payne, M.L.
Nebraska University, Scottsbluff.
Paper No. 78-2546, Presented at the 1978 winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 13 p. 3 fig, 4 ref.
?*MnnPtarSi\ F^rOW ^gation, Valves, Control systems, Automation, Instrumen-
tation, Application equipment, Electronic equipment, Irrigation systems.
Research was conducted during the summers of 1977-1978 on an USDA-SEA controller
to allow semi-automatic changing of furrow irrigation sets. Two types of control
valves were used with the controller. After initial diff iculties , satisfactory
use was obtained with the controller and both types of valves. Additional work
in an on-farm situation was advised before the controllers use is recommended.
78:03F-118
DIGITAL CONTROLLER FOR TRICKLE IRRIGATION,
Fangmeier, D.D., and Busman, J.D.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Paper No. 78-2547, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago?
Illinois, 7 p. 5 fig, 1 tab, 5 ref.
Contr°l systems, Irrigation systems, Water conservation, Electronic
use
, rvaon, ec
ipment, Evaporation, Soil moisture, Moisture tension, Timing, Consumptive
, Application equipment.
er *aa*eBi<3ne* U8i*g complementary metal oxide semiconductor
™sr * controller uses measured evaporation pan depths and- soil
moisture tensions to determine the time required to apply the desired
of water on a daily basis. Circuit diagrams for major components
78:03F-119
RESPONSE OF CORN TO LIMITED IRRIGATION ON SANDY SOILS,
Wilson, G.D. , Watts, D.G., and Fischbach, P.E.
2at«r8S U™V^ity£ N°rth ?latte' Department of Agricultural Engineering.
of lari-Jn™? *' *resented at the ^78 Winter Meeting of the American Society
Ulinois S o En9ineers, December 18-20, 1978' ^Uner House Hotel, Chicago,
(See 5^621-040)
152
-------
78:03F-120
EVALUATION OF CROP WATER STRESS UNDER LIMITED IRRIGATION,
Heermann, D., and Duke, H.
Agricultural Research, Science and Education Administration, Fort Collins,
Colorado, United States Department of Agriculture.
Paper No. 78-2556, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicaero
Illinois, 5 p. 8 fig, 8 ref.
(See 78:021-041)
78:03F-121
IRRIGATED CORN YIELD RESPONSE TO WATER,
Musick, J.T., and Dusek, D.A.
Southwestern Great Plains Research Center, Bushland, Texas, United States
Department of Agriculture.
Paper. No. 78-2557, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 26 p. 8 fig, 3 tab, 16 ref.
(See 78:021-042}
78:03F-122
CORN YIELD RESPONSES TO WATER STRESS MANAGEMENT,
Stegman, E.G., and Aflatouni, M.
North Dakota state University, Fargo, Department of Agricultural Engineering.
Paper No. 78-2558, Presented at the 1978 Winter Meeting of the American'Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 9 p. 8 fig, 3 tab, 18 ref, 1 equ.
(See 78:021-034)
78:03F-123
HARVESTING RUNOFF FROM PRECIPITATION ON IRRIGATED LANDS,
Manges, H.L., and Mao, L.-T.
Kansas Agricultural Experiment Station, Manhattan, Kansas.
Paper No. 78-2559, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 10 p. 2 fig, 3 tab, 10 ref, 11 equ.
Descriptors: Water harvesting, Runoff, Precipitation (atmospheric), Tailwater,
Climatic data, Model studies, Evapotranspiration, Water balance, Irrigation,
Corn Cfield).
A tailwater management model was developed to simulate runoff from precipitation
on irrigated land. The model was tested for corn using 25 years of climatological
data for Garden City, Kansas. Runoff from precipitation repumped onto the field
averaged 69 and 39 millimeters annually for two commonly irrigated soils.
>
78:03F-124
THE TIMELINESS BENEFIT OF SUBSURFACE DRAINAGE,
Wendte, L.W., Drablos, C.J.W., and Lembke, W.D.
Soil Conservation Service, Kankakee, Illinois.
Transactions of the American Society of Agricultural Engineering, Vol. 21, No. 3,
p 484-488, May-June, 1978. 6 fig, 3 tab, 21 ref.
Descriptors: *Subsurface drainage, *Agriculture, *Benefits, *Model studies,
Mathematical models, Planting management, Farm management, Drains, Tile drains,
Economics.
A simulation model was developed to predict available spring workdays and the
earliest possible planting dates for soils with a subsurface drainage system.
Applying the model to two Illinois soils, it was found that as many as two available
workdays in April and 19 days in May are gained by installing a recommended sub-
surface drainage system. The optimum drain spacing based on the timeliness benefit
of earlier corn planting ranged from 24 to 61 m, depending on permeability and soil
type. The average annual timeliness benefit for installing the optimum subsurface
drainage system was $37 to $156/ha.
153
-------
78.-03F-125
WATER TABLE DEPTH AND IRRIGATION EFFECTS ON WATER USE EFFICIENCIES OF THREE CROPS,
Benz, L.C., Reichman, G.A., Doering, E.J., and Follett, R.F.
Agricultural Research Service, Northern Great Plains Research Center, Mandan,
North Dakota.
Paper No. 77-2039 presented at the 1977 Annual Meeting of the American Society of
Agricultural Engineers, June 26-29, 1977, Raleigh, North Carolina, 17 p. 7 fig,
3 tab, 14 ref.
Descriptors: *Corn (field), *Sugarbeets, *Water table, Irrigation effects, *Alfalfa*
Irrigation, Irrigation efficiency, Irrigation practices.
Production and applied water-use efficiencies (AWUE) of corn, sugarbeets, and alfalf*
from a 3-year field experiment at three water table depths and four irrigation rates
were highest from the shallow water table treatment without irrigation.
78.-03F-126
ESTIMATING SPRINKLER DISTRIBUTION PATTERNS USING LINEAR REGRESSION,
Karmeli, D.
Colorado State University, Fort Collins, Department of Agricultural and Chemical
Engineering.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 4, p 682-686, August 20, 1978. 5 fig, 2 tab, 5 ref, 9 equ.
Descriptors: Sprinkler irrigation, Distribution patterns, Estimating equations,
Regression analysis, Spatial distribution.
The linear regression was used to describe sprinkler distribution patterns. The
linear fit was found to approximate the distribution very well in a wide range.
This approximation proved to produce good estimates for both high and low quality
distributions. In the higher quality distributions, the linear regressions model
estimated the actual field data as well as the normal model. However, in lower
quality distributions the linear regression model proved significantly better than
the normal model in its estimates. A new coefficient, UCL, was suggested for
practical use.
78:03F-127
TRICKLE IRRIGATION UNIFORMITY AND EFFICIENCY,
Solomon, K., and Keller, J.
Rain Bird Technical Services, Glendora, California.
Journal of the Irrigation and Drainage Division, American Society of Civil Engineer*1
Vol. 104, No, IR3, p 293-306, September, 1978. 5 fig, 1 tab, 8 ref, 16 equ.
Descriptors: Irrigation efficiency, Irrigation practices, Water conservation,
Uniformity coefficient, Water pressure, Water distribution (applied), Pressure
head, Design criteria.
Expressions were developed for the pressure head in a trickle irrigation lateral
and throughout the pipe network for three common types of manifolds. Histograms
were drawn showing the distributions of pressure in typical trickle irrigation
systems. The distributions were skewed toward the low head end, and the degree
of s,kew depended on the type of manifold and the ratio of manifold head loss to
lateral head loss. Flow rate histograms were drawn showing the combined effects
on emitter discharge spread, manifold construction, head losses and variation in
emitter manufacture. Coefficient of manufacturing variation was shown to be as
important a design consideration as the amount of head loss in the system. Values
of emission uniformity and absolute emission uniformity were tabulated for various
emitter and system configurations on level ground. It was pointed out that in
many cases the results of this study can be applied to sloping terrain as well.
78s03F-128
AUTOMATION OF ON-FARM IRRIGATION TURNOUTS UTILIZING JACK-GATES,
Dedrick, A.R., and Erie, L.J.
United States Water Conservation Laboratory, Phoenix, Arizona.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 1, p 92-96, February 20, 1978. 6 fig, 3 tab, 7 ref.
154
-------
Descriptors: Irrigation, Surface irrigation, Automation, Automatic control,
Turnouts.
The design, development, and installation of equipment used to automate existing
single outlet turnouts (jack-gates) on a 26.3-ha (65-acre) field were described.
Specific jack-gate modifications and equipment requirements; control center
design associated with safety overflow, excess water after irrigation, and
sequencing functions; and system operations were all discussed.
78:03F-129
THE ROLE OF EVAPOTRANSPIRATION MODELS IN IRRIGATION SCHEDULING,
Jensen, M.E., and Wright, J.L.
Snake River Conservation Research Center, United States Department of Agriculture-
Agricultural Research Service, Kimberly, Idaho.
Transactions*of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 1, p 82-87, February 20, 1978. 4 fig, 2 tab, 25 ref, 3 equ.
(See 78:020-007)
78:03F-130
AUTOMATION OF AN OPEN-DITCH IRRIGATION CONVEYANCE SYSTEM UTILIZING TILE OUTLETS,
Erie, L.J., and Dedrick, A.R.
United States Water Conservation Laboratory, Phoenix, Arizona.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 1 p 119-123, February 20, 1978. 6 fig, 6 ref.
Descriptors: Irrigation ditches, Automation, Automatic control, Tiles,
Irrigation, Conveyance structures.
Nearly 80% of the irrigated lands in the United States use surface irrigation
techniques. Most of the on-farm, irrigation-water distribution systems are of
the open-ditch type. The latest trend in western Arizona and parts of California
is to dead-level fields, then irrigate from single or multiple outlets with large
streams of water. These level basins are well adapted to automation. An automated
irrigation system reduces farm labor requirements and, as an irrigation management
tool, can reduce water application, improve crop production, and minimize scalding
and thus stand loss. A 28.4-ha (70-acre) field irrigated with tile outlets was
pneumatically automated using two types of pillows on the outlet side, in combina-
tion with automated jack-gates, from a centrally located concrete-lined canal.
The present system is being used by the farmer, observed and amended by the
researchers, and demonstrated to many U.S. and foreign visitors.
155
-------
SECTION XVI
WATER QUANTITY MANAGEMENT AND CONTROL
CONTROL OF WATER ON THE SURFACE (GROUP 04A)
78:04A-001
A STOCHASTIC MODEL OF THE OPERATION OF A STREAM-AQUIFER SYSTEM,
Flores, E.Z., Gutjahr, A.L., and Gelhar, L.W.
New Mexico Institute of Mining and Technology, Socorro.
Water Resources Research, Vol. 14, No. 1, p 30-38, February, 1978. 3 fig, 1 tab,
34 ref.
Descriptors: *Reservoir operation, *Stochastic processes, *Linear programming,
*Water management (applied) , Optimization, Aquifers, Streams, Decision making.
Effects, Wells.
A simple lumped parameter stochastic model for optimal water management in a
stream-connected aquifer system is examined. The physical system is represented
by a linear reservoir model, and a conditional probability approach is used to
estimate the effect of parameter variability. A drawdown correction is used to
incorporate the local drawdown of the wells and is a crucial part of the model.
A management analysis is accomplished by using a linear decision rule to minimize
the expected value of the discounted costs with appropriate chance constraints,
and the resulting nonlinear optimization problem is solved iteratively using a
standard linear programming package. In order to evaluate the limitations of the
lumped parameter model in a management context, the results of the management
technique are compared with results from Maddock (1974) who used a distributed
representation of the aquifer. The conclusions of this analysis indicate that
stochastic effects are not very important in arriving at an operating policy but
are important in determining the expected cost.
78:04A-002
A VARIATIONAL INEQUALITY METHOD APPLIED TO FREE SURFACE SEEPAGE FROM A TRIANGULAR
DITCH,
Bruch, J.C., Jr., and Sloss, J.M.
California University, Santa Barbara, Department of Mechanical and Environmental
Engineering.
Water Resources Research, Vol. 14, No. 1, p 119-124, February, 1978. 2 fig,
2 tab, 12 ref.
Descriptors: *Mathematical models, *Seepage, *Ditches, Drains, Equations, Ground-
water movement. Numerical analysis, Free surfaces, Soils, Depth.
Two-dimensional seepage from a single triangular channel into permeable soil
underlain at a finite depth by a drain was solved by reducing the problem to a
variational inequality. The results obtained consist of the location of the free
surface, and thus, the shape of the seepage region, the velocity potential and
stream function at a series of mesh points, and the seepage flow rate. The
successive overrelaxation method with projection was used to solve the-numerical
problem. The numerical results compared very favorably with the analytical
solution to the same problem.
78:04A-003
INTERTEMPORAL ALLOCATION OF IRRIGATION WATER IN THE MAYURAKSHI PROJECT (INDIA),
AN APPLICATION OF CHANCE-CONSTRAINED LINEAR PROGRAMMING,
Maji, C.C., and Heady, E.O.
Indian Agricultural Research Institute, New Delhi, Water Technology Centre.
Water Resources Research, Vol. 14, No. 2, p 190-196, April, 1978. 10 tab, 29
equ, 14 ref.
156
-------
Descriptors: "Irrigation water, *Water allocation (applied), *Linear program-
ming, *Reservoir operation, "Cropping pattern, *Chance-constrained models,
Projects, Water policy, Optimization, Economic efficiency.
Developed is an optimal cropping pattern and a reservoir management policy for
the Mayurakshi irrigation project in India. Two chance-constrained linear
programming models are formulated to account for the stochastic nature of the
monthly inflows. The models also consider the increased economic opportunity
offered by the introduction of new high-yielding crop varieties. The results
clearly indicate that a change in the existing cropping pattern and reservoir
management policy is desirable and is consistent with the maximization of net
return to the project area. The existing supply of nitrogen fertilizer in the
command area is found to be inadequate to allow for the best use of other re-
sources, including irrigation water. As the probability of occurrence of a
drought or a flood is kept within a limit of 10%, the crop activities in the
optimal cropping pattern suffer from drought or flood conditions no more than
10% of the time. Thus the resulting cropping patterns should be preferred by
the -tradition-bound farmers of the command area, who have a low risk-bearinq
ability. y
78:04A-004
SEQUENTIAL EXPLICITLY STOCHASTIC LINEAR PROGRAMMING MODELS: A PROPOSED METHOD
FOR DESIGN AND MANAGEMENT OF MULTIPURPOSE RESERVOIR SYSTEMS,
Houck, M.H., and Cohon, J.L.
Purdue University, Lafayette, Indiana, School of Civil Engineering.
Water Resources Research, Vol. 14, No. 2, p 161-169, April, 1978. 12 ref.
Descriptors: "Multiple-purpose reservoirs, *Reservoir design, "Reservoir
operation, "Linear programming, "Stochastic processes, "Nonlinear programming,
"Economic efficiency, Optimization, Water management (applied), Operating rules.
A sequential explicitly stochastic linear programming model (SESLP) which con-
sists of a nonlinear program and an algorithm for obtaining an approximate solu-
tion is presented. The SESLP model can be used to determine for a multipurpose
multiple-reservoir system either both a design and a management policy or only a
management policy. , A discrete lag-one Markov process is explicitly included in
the model as the streamflow description. The approximate solution to the non-
linear program is obtained by sequentially solving two linear programs which are
subsets of the nonlinear program. A method of significantly reducing the compu-
tational burden and data requirements of the SESLP model is also presented. The
method (system coordinated performance-individual operation (Scorpio)) is effec-
tive because within the SESLP/Scorpio model, although the operating rules for
each reservoir are dependent on events occurring only at that reservoir site,
system-wide performance levels are measured and the operation of each reservoir
is coordinated with all other reservoirs. Problem objectives include food loss
minimization and benefit maximization.
78:04A-005
EFFECT OF DRAIN TUBE OPENINGS ON WATER-TABLE DRAWDOWNS,
Skaggs, R.W.
North Carolina State University at Raleigh, Department of Biological and Agricul-
tural Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No 1R1, Proceedings Paper 13606, p 13-21, March, 1978. 5
fig, 2 tab, 13 ref, 1 append.
Descriptors: "Tile drainage, "Drawdown, "Model studies, Mathematical models,
Drains, Tile drains, Groundwater, Soil water, Soil water movement, Filters.
Conventional methods assume that the drain tube is completely open and offers no
resistance to the entry of water. An approximate method of determining the
effect of drain tube openings on water table drawdown was presented, based on the
use of Hooghoudt's equivalent depth to account for convergence near the drain
during water table drawdown. Data from the literature were used to define an
effective drain tube radius, r sub e, for drains with a finite number of open-
ings. The r sub e value was used then to define the Hooghoudt equivalent depth
which was, in turn, used in solutions to the Boussinesq equation for water table
157
-------
drawdown. The use of an envelope wrap material will permit a somewhat wider
drain spacing for all cases with a large increase in spacing for the deeper
profile. The allowable increase in spacing for both cases was relatively small,
and the total system cost with the envelope wrap was about 6% higher than with-
out the wrap for the shallow profile and about 7% lower for the deep profile.
78:04A-006
HYDROLOGIC IMPACT OF GRAZING ON INFILTRATION: A CRITICAL REVIEW,
Gifford, G.F., and Hawkins, R.H.
Utah State University, Logan, College of Natural Resources, Watershed Science
Unit.
Water Resources Research, Vol. 14, No, 2, p 305-313, April, 1978. 5 fig, 4 tab,
37 ref.
Descriptors: Grazing, Infiltration, Infiltration rates, Hydrologic aspects,
Reviews, Ranges, Runoff, Hydrographs, Water yield.
The hydrologic importance of grazing is receiving increased attention on range-
lands in the United States. The literature on this topic is fragmented. This
paper explores the available literature for information useful in understanding
the hydrologic impacts of grazing intensity as related primarily to infiltration
and runoff. Generally, data relative to range condition are not adequate for
evaluating hydrologic impacts. Data relating grazing intensity to infiltration
rates are available, yet distinct limitations are evident. These limitations
are discussed in terms of identifying future research needs. The greatest need
appears to be a detailed definition of the long-term effects of grazing (by year
and season) on infiltration rates as a function of site, range condition, and
grazing intensity. Once obtained, infiltration rates must be coupled with an
appropriate method for generating runoff volumes, storm hydrographs, and long-
term water yields.
78:04A-007
A KINEMATIC MODEL FOR SURFACE IRRIGATION,
Sherman, B., and Singh, V.P.
New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801.
Water Resources Research, Vol. 14, No. 2, p 357-364, April, 1978. 10 fig, 41
ref, 46 equ.
Descriptors: Surface irrigation, Mathematical models, Analytical techniques,
Infiltration, Hydrodynamics, Momentum equation.
A kinematic wave model is developed to study surface irrigation. Depending on
the variability of infiltration and the kinematic wave friction parameter, three
cases are distinguished. Explicit analytical solutions are obtained for the
case when infiltration is constant, and a possible approach is suggested for the
case when it is not.
78:04A-008
RESERVOIR STORAGE WITH DEPENDENT, PERIODIC NET INPUTS,
Troutman, B.M.
Geological Survey, Denver, Colorado, Water Resources Division.
Water Resources Research, Vol. 14, No. 3, p 395-401, June, 1978. 5 fig, 20 ref.
Descriptors: *Reservoirs, *Reservoir storage, *Storage capacity, *Projections,
^Stochastic processes, Inflow, Water demand, Time series analysis. Seasonal,
Storms.
Two random quantities, the range and the maximum deficit, which may provide a
measure of the required storage capacity of a reservoir over a fixed length of
time, are considered. Interest in the range from an engineering point of view
was initiated by Hurst (1951), who demonstrated that for certain geophysical
time series, sample values of the range exhibit a property that has subsequently
become known as the "Hurst phenomenon". This property is discussed briefly,
primarily with the intention of showing that the Hurst phenomenon can be inter-
preted so as to be consistent with the asymptotic results on the range. The
second quantity, the maximum deficit, is simply the.storage obtained when one
158
-------
applied the sequent peak algorithm. Of primary concern is the manner in which
the statistical behavoir of these quantities is affected by dependence and per-
iodicity in the net inputs to the reservoir. Dependence, sometimes referred to
as persistence or serial correlation, is seen, for example, in the fact that a
large stream discharge on a given day will tend to be followed by a large dis-
charge on the next day. The periodicities are due primarily to seasonal
variations in factors such as precipitation and demand for stored water.
78:04A-009
FLAT CHANNEL TERRACES FOR POLLUTION ABATEMENT AND SEDIMENT CONTROL,
Buchta, H.G., Liesemeyer, W.W., and Jackson, L.G.
United States Department of Agriculture, Soil Conservation Service, Grand Island,
Nebraska.
Paper No. 78-2521, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 5 p. 1 fig, 4 ref.
Descriptors: Terracing, Pollution abatement, Sediment control, Runoff, Crop
production, Semiarid climates, Computer programs, Diversion, Gullies, Nebraska.
Flat channel terraces have been effectively used to control and use runoff
water. The runoff can help stabilize crop production in a simiarid climate.
Parallel flat channel terraces are growing in popularity.
78:04A-010
PARALLEL TERRACES ON FLAT SLOPES,
Fryrear, D.W., and Archer, E.
United States Department of Agriculture, Big Spring, Texas.
Paper No. 78-2522, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 15 p. 2 fig, 1 tab, 8 ref.
Descriptors: Terracing, Slopes, Slope stabilization, Soil conservation, Water
conservation, Crop production, Dryfarming, Texas, Runoff, Economic justification.
West Texas has more terraces constructed each year then most states. This manu-
script describes the design, layout, and construction of parallel terracing
systems in this part of the state. Several farmers were interviewed concerning
their feelings about parallel terraces and why they are used on their farms.
The farmers are enthusiastic with the benefits of terraces particularly if they
are involved in the design and construction of the system. Despite the point
rows, more skilled operators, and increased time in the field, some producers
feel that the increased production from terraced fields will pay for the con-
struction costs in four to five years.
78:04A-011
DESIGN AND OPERATION OF GRADIENT TERRACE SYSTEMS,
Bondurant, D.T., and Laflen, J.M.
Soil Conservation Service, Des Moines, Iowa.
Paper No. 78-2520, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 7-p. 4 fig, 5 tab, 19 ref.
(See 78:02J-006)
78:04A-012
LAND USE EFFECTS ON CLAYPAN SOIL HYDROLOGY,
Kramer, L.A., and Burwell, R.E.
Science and Education Administration, Federal Research, Columbia, Missouri, United
States Department of Agriculture.
Paper No. 78-2070, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 14 p. 7 tab, 5 ref.
Descriptors: Land use, Water yield, Land management, Clays, Runoff, Surface
runoff, Corn (field), Wheat, Fallowing, Pastures.
159
-------
Water yield data from 0.02-acre research plots for a ten-year study period of
constant land use treatments are presented. The SCS Curve Number Procedure for
runoff prediction gave ten-year average annual runoff values very similar to the
observed land cover of fallow, continuous corn, small grain, and rotation
meadow.
78:04A-013
CONTROLLING IRRIGATION RUNOFF LOSSES WITH PROPER MANAGEMENT,
Fitzsimmons, D.W., Busch, J.R., Lewis, G.C., and Berg, C.W.
Idaho University, Moscow, Department of Agricultural Engineering.
Paper No. 78-2090, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 14 p. 1 fig, 9 tab,
8 ref.
Descriptors: Surface runoff, Runoff, Tailwater, Erosion, Water management (applied) i
Pollutants, Surface irrigation, Water loss, Sediment control, Nutrient removal.
Field investigations to determine the effectiveness of irrigation, tillage and
other practices in controlling surface runoff and resulting pollutant losses
from surface-irrigated fields were conducted during two irrigation seasons. The
results indicate that water, sediment and nutrient losses can be reduced or
eliminated by the use of proper management practices.
78:04A-014
CHEMICAL CHARACTERIZATION OF THE GASEOUS AND LIQUID ENVIRONMENTS OF SUBSURFACE
DRAIN SYSTEMS,
Meek, B.D., Grass, L.B., and MacKenzie, A.J.
Imperial Valley Conservation Research Center, Brawley, California.
Soil Science Society of America Journal, Vol. 42, No. 5, p 693-698, September-
October, 1978. 3 fig, 6 tab, 14 ref.
(See 78:02K-052)
78:04A-015
EFFECTS OF DRAINAGE PROJECTS ON RUNOFF FROM DEPRES.SIONAL WATERSHEDS,
Moore, I.D., and Larson, C.L.
Minnesota University, St. Paul, Department of Agricultural Engineering.
Paper No. 78-2504, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 5 p.
Descriptors: Drainage effects, Drainage practices, Surface drainage. Subsurface
drainage, Surface runoff, Subsurface runoff. Peak discharge, Small watersheds,
Mathematical models, Statistical methods.
Runoff from watersheds characterized by numerous depressions was studied
statistically and by use of a special purpose watershed model. Application of
the model to two small watersheds indicated that drainage development increases
annual runoff, storm runoff and peak discharges.
78:04A-016
LEACHING CONTROL CAN'T BE PERFECT,
Larsen, R.
Irrigation Age, Associate Editor.
Irrigation Age, Vol. 13, No. 2, p 49, October, 1973. 1 fig.
Descriptors: Leaching, Leachate, Nitrogen, Nitrates, Irrigation, Scheduling,
Water pollution, Nebraska.
This article reported the study to minimize losses from leaching conducted on
sandy soils by some members of the Agricultural Engineering Department, University
of Nebraska-Lincoln. The major conclusion of the study was that scheduling
of irrigations to minimize percolation and proper selection of nitrogen (N)
amount and source can have a significant effect on nitrate leaching loss when
corn is produced on sandy soils. The study, however, indicated that reducing
the loss to zero is not a practical goal on sandy'soils.
160
-------
78:04A-017
INFLUENCE OF ROW SPACING OF GRAIN SORGHUM ON GROUND COVER, RUNOFF, AND EROSION,
Adams, J.E., Richardson, C.W., and Burnett, E.
Grassland, Soil and Water Research Laboratory, P.O. Box 748, Temple, Texas
76501.
Soil Science Society of America Journal, Vol. 42, No. 6, p 959-962, November-
December, 1978. 4 fig, 2 tab, 9 ref.
Descriptors: Runoff, Surface runoff, Erosion, Soil erosion, Canopy, Rainfall,
Rainfall intensity, Grain sorghum. Cover crops.
A study was begun at Temple, Texas, in 1972 to assess the effect of narrow (50-cm)
and conventional (100-cm) row spacing of grain sorghum on runoff and erosion from
field-sized areas. Sorghum in narrow rows established a more complete plant
canopy earlier than sorghum with conventional row spacing and provided more ground
cover for much of the growing season. In 1973, runoff was 45% less and soil loss
was 39% less from narrow-row grain sorghum than from sorghum with conventional
row spacing. Narrow-row spacing of sorghum increased ground cover significantly
(5% level) 35 days after emergence in 1974. Canopy cover was at maximum by 63
days after seeding emergence and provided a ground cover of 46 and 81% for sorghum
with 100- and 50-cm row spacing, respectively.
78:04A-018
SEEPAGE CONTROL BY PARTICLE SIZE SELECTION,
Hauser, V.L.
Science and Education Administration, Temple, Texas, Grassland-Forage .Research
Center.
Transactions of the American Society of Agricultural Engineers, Vol. 21, No. 4,
p 691-695, July-August, 1978. 9 fig, 1 tab, 12 ref. .
Descriptors: *Linings, *Clays, *Gravels, *Aggregates, *Seepage control, Canal
linings, Reservoirs, Canals, Hydraulic conductivity, Permeability, Soils, Sands,
Seepage.
Earth linings are used frequently in reservoirs, canals, and other earth structures
to control liquid movement for the purposes of pollution control, water conserva-
tion, and structural stability. Clays or chemicals often are added to linings to
reduce the hydraulic conductivity of the native soil; however, both additives
sometimes decrease in effectiveness with time. Under ordinary conditions, gravel
is nearly inert and does not change properties with time. The hydraulic conductivity
of permeable soil was reduced substantially by adding gravel that was at least 15
times larger than the particle size of the soil. The amount of clay required to
control seepage was reduced by half by the addition of gravel.
161
-------
SECTION XVII
WATER QUANTITY MANAGEMENT AND CONTROL
GROUNDWATER MANAGEMENT (GROUP 04B)
78:048-001
WATER SUPPLY DILEMMAS OF GEOTHERMAL DEVELOPMENT IN THE IMPERIAL VALLEY OF
CALIFORNIA,
Layton, D.W.
California University, Livermore, Lawrence Livermore Laboratory.
Water Resources Bulletin, Vol. 14, No. 1, p 133-143, February, 1978. 4 fig,
22 ref.
Descriptors: *Geothermal studies, *Therraal powerplants, *California, *Cooling
water, *Water supply, *Imperial Valley (California), *Salton Sea (California),
Water resources, Powerplants, Water requirements.
There are four known geothermal resource areas in the Imperial Valley that have
a combined potential of over 4,000 megawatts of electrical energy for 25 years.
Water resources available to support geothermal energy development are imported
Colorado River water, agricultural waste waters, Salton Sea water, and ground-
water. In addition, geothermal power plants can produce their own cooling water
from steam condensate. Nevertheless, the relatively high water requirements of
geothermal facilities along with a series of real and potential constraints may
cause water supply dilemmas involving both the acquisition and use of cooling
water. Important constraints are institutional policies, water supply costs,
technical problems, and impacts upon the Salton Sea. These constraints and
related dilemmas were examined in light of relevant information on the valley's
water resources, geothermal resources and energy technologies, cooling water
requirements, and water supply options.
78:04B-002
ARTIFICIAL GROUNDWATER RECHARGE WITH CAPILLARITY,
Ortiz, N.V., Duke, H.R., Sunada, O.K., and McWhorter, D.B.
Colorado State University, Fort Collins, Department of Civil Engineering.
'journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. 1R1, Proceeding Paper 13627, March, 1978. 11 fig,
1 tab, 21 ref.
Descriptors: *Groundwater recharge, *Capillary action, *Artificial recharge,
•Numerical analysis, *Model studies, *Capillary flow, *Capillary zone, *Ground-
water mounds, Water table, Porous media.
The effect of capillarity on the transient response of the water table to
recharge was evaluated by a numerical and a porous media model. The numerical
model was developed to simulate the growth and spread of groundwater mounds,
taking into consideration the flow and storage in the capillary regions. The
contribution 'from the capillary region was described analytically in terms of
recharge rates and the measureable soil properties of bubbling pressure, pore-
size distribution index, and hydraulic conductivity. The numerical model was
verified by comparing its predictions for various flow conditions with the
result obtained from the porous media model. The effects of bubbling-pressure
head, pore-size distribution index, initial saturated depth, depth to water
table, and recharge rate on the predicted mound height were determined. It was
shown that the effect of the capillary region significantly influences the
growth and spread of groundwater mounds.
78:04B-003
DIURNAL PERIODICITY IN GROUNDWATER RECHARGE RATES,
Webb, S.N., and Watson, K.K.
162
-------
New South Wales University, Kensington, Australia, School of Civil Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IRl, Proceedings Paper 13613, March, 1978. 2 fig,
1 tab, 11 ref.
Descriptors: *Groundwater recharge, *Groundwater, *Algae, *Permeability,
*Pore pressure, *Diurnal, *Australia, Frequency, Pore water, Pit recharge.
In an investigation of the flow characteristics of a recharge pit used for
artificial groundwater recharge purposes, diurnal variations of a cyclic nature
were detected in the intake rate. The output from soil water pressure sensors
installed between the base of the pit and the water table indicated similar
cyclic variations. The maximum intake rate occurred regularly each day at
approximately 2 a.m. - 3 a.m. and the minimum approximately 12 hours later. It
was concluded that these variations are due to the activity of algae on the base
of the pit and in the top layer of sand. Diurnal peaks and troughs of the algae
oxygen production result in changes in the hydraulic conductivity of the pro-
file. This would appear to be related to changes in the volume of the occluded
oxygen which exists as bubbles in the soil pores. These reduce the flow area
available for recharge and thus cause a reduction in the intake rate.
78:046-004
MANAGEMENT ASPECTS OF CYCLIC STORAGE OF WATER IN AQUIFER SYSTEMS,
Greydanus, H.W.
State of California, Resources Agency, Department of Water Resources, Box 388,
Sacramento 95802.
Water Resources Bulletin, Vol. 14, No. 2, p 477-480, April, 1978.
Descriptors: Aquifer systems, Groundwater basins, Water storage, Water manage-
ment (applied), California, Legal aspects, Water quality, Water rights, Water
law, Environmental effects.
Most of California's precipitation falls at the wrong place in the wrong season
in relation to the water needs. Redistribution and regulation are essential.
Aquifer systems - groundwater basins - can provide a share of the future cyclic
storage regulation. There are some differences in management concepts in using
a full basin in comparison with a partially dewatered basin. Legal, water
quality, and physical impacts on aquifer systems, including subsidence, are
concerns. Storage may be for the benefit of overlying water users or for dis-
tant areas. Extraction during dry periods or recharge methods will require
careful planning. Existing rights and uses and equitable treatment of all
parties must be assured. Financial compensation may be involved. Changes in
methods of operation or degree of self-determination by affected water agencies
will require committed watermanship to resolve. Legislation or amendments to
organic acts may be needed but much can be accomplished within existing statutes.
Environmental impacts which can be avoided by not using large surface storage
sites are important. Energy for pumping will be a key consideration. About
40% of California is underlain by aquifer systems. This resource offers major
potential in overcoming the maldistribution of natural water resources.
78:048-005
SUBSURFACE DRAINAGE OF AN ALLUVIAL CLAY SOIL FOR SOYBEANS,
Carter, C.E., and Camp, C.R.
P.O. Drawer U, University Station, Baton Rouge, Louisiana 70893.
Paper No. 78-2040, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 6 p. 3 fig, 2 tab,
7 ref.
Descriptors: Subsurface drainage. Subsurface drains. Soybeans, Crop response,
Crop production, Clays, Louisiana, Economic feasibility.
A subsurface drainage field experiment was conducted on a 4 ha site of an
alluvial clay soil in Tensas Parish, Louisiana, during 1974-1977. Subsurface
drains spaced 7.5 and 15 m apart did not effectively control the water table but
the soil water regime near the drains was improved somewhat. Soybean yields were
significantly increased by this improved drainage three of four years with drains
spaced 7.5 m apart and two of four years with drains spaced 15 m apart.
163
-------
78:048-006
FIELD EVALUATIONS OF GROUNDWATER CONTROL BY TRENCH AND TRENCHLESS METHODS OF
INSTALLED DRAINS—LOWER RIO GRANDE VALLEY OF TEXAS,
Vittetoe, G.C., and Garner, B.J.
Soil Conservation Service, Temple, Texas, United States Department of Agricul-
ture.
Paper No. 78-2043, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Utah, 6 p. 7 fig.
Descriptors: Subsurface drainage, Subsurface drains, Drainage practices,
Trenches, Installation, Salinity, Flow rates, Groundwater, Water quality con-
trol, Texas.
This paper presents the result of field evaluations of the flow performance of
209 subsurface drainage systems in the Lower Rio Grande Valley of Texas. These
drain systems are installed to control groundwater and serve as artificial sub-
surface drainage arteries for salinity management in an irrigated area. Of the
209 examined installations, 141 were installed by the trench method and 68 by
the trenchless method. All systems were installed in calendar years 1975 and
1976, and all utilized perforated corrugated plastic tubing, of 4- to 6-inch
diameter size, and nylon fabric filters. The evaluations reveal the ability
Of the 209 drain systems to discharge flow in the prescence of a groundwater
flow source, with the surface of the groundwater variously ranging from 2 to 6
feet below the ground surface. The data displays a strong general disparity in
the unit flow for systems installed by the trench and trenchless methods, with
the trench method showing a noticeably higher flow performance for seemingly
similar conditions. In repeated instances, the flow performances of systems
installed by the trenchless method were less than that believed to be needed to
satisfy minimal drainage coefficients for the area.
78:04B-007
ANALYSIS OF COMBINATION SURFACE-SUBSURFACE DRAINAGE SYSTEMS FOR HUMID REGION
SOILS,
Skaggs, R.W.
North Carolina State University, Raleigh, Department of Biological and Agricul-
tural Engineering.
Paper No. 78-2541, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 16 p. 13 fig, 5 tab, 20 ref, 3 equ.
Descriptors: Surface drainage, Subsurface drainage, Drainage systems, Drainage,
Simulation analysis, Trafficability, Humid areas, Humid climates, Model studies,
Crop production.
Various designs of combination surface-subsurface drainage systems were analyzed
by simulating their performance over twenty-five years of climatological record.
Simulations were conducted and results analyzed for four soils at three loca-
tions: Jacksonville, Florida, Wilmington, North Carolina, and Columbus, Ohio.
78-.04B-008
INCORPORATING CROP NEEDS INTO DRAINAGE SYSTEM DESIGN,
Ravelo, C.J., Reddell, D.L., Hiler, E.A., and Skaggs, R.W.
Texas A & M University, College Station, Department of Agricultural Engineering.
Paper No. 78-2540, Presented at the 1978 Winter Meeting of the American-Society
of Agricultural Engineers, December 18-20, -1978, Palmer House Hotel, Chicago,
Illinois, p 20.
Descriptors: Drainage practices, Drainage systems, Drainage, Computer models,
Water table, Soil water, Soil-water-plant relationships, Simulation analysis,
Crop production, Water management (applied).
An improved approach is proposed for incorporating crop drainage requirements
into drainage design procedures. The overall methodology links crop drainage
requirements, climatological data, and drainage theory into a workable design
method through incorporation of the stress-day index concept into a water manage-
ment model. (Skaggs, 1975. A water management model for high water table soils-
Paper No. 75-2524, ASAE Winter Meeting.)
164
-------
78:04B-009
SUBSURFACE DRAIN SPACING FROM WATER TABLE AND OUTFLOW MEASUREMENTS,
Michener, D.W., Schwab, G.O., Skaggs, R.W., Gordos, J.D., and Olosky, C.J.
North Carolina State University, Raleigh, Department of Biological and Agricul-
tural Engineering.
Paper No. 78-2536, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 12 p. 2 fig, 8 tab, 6 ref.
Descriptors: Subsurface drains, Subsurface drainage, Water table, Drawdown,
Hydraulic conductivity, Porosity, Discharge measurement, Soil texture, Design,
Statistical methods.
Hydraulic conductivity and drainable porosity were determined from water table
drawdown and outflow measurements for six fine-textured soils in Ohio. Drain
spacings were computed for three drawdown rates with a coefficient of variation
of about 30%. When drawdown was corrected for evapotranspiration, spacings were
reduced about 16%.
78:048-010
RESEARCH INTO THE EFFECTS OF ARTIFICIAL GROUNDWATER RECHARGE, LEA VALLEY,
LONDON,ENGLAND,
Edworthy, K.J., Stott, D.A., and Wilkinson, W.B.
Water Research Centre, Medmenham, England, Resources Division.
Water Resources Bulletin, Vol. 14, No. 3, p 554-575, June, 1978. 11 fig, 2 tab,
9 ref.
Descriptors: *Groundwater, *Artificial recharge, *Recharge wells, *Lea Valley
(England), *London Basin (England), Aquifers, Chalk, Sands, Wells, On-site
investigations.
Large-scale groundwater abstraction from the Cretaceous Chalk/Lower Tertiary
Basal Sands aquifer system of the London Basin in the last 150 years has devel-
oped storage of more than 1,000,000 cu m. Limited operational recharge was
undertaken in the 1950's encouraging further detailed study of the wider possi-
bilities. Following a comprehensive hydrogeological reappraisal, an economic
and engineering study, and pilot-scale experiments, the Lea Valley was shown to
have the greatest potential for recharge. Artificial recharge into the Chalk at
a rate of 9,000 cu m/d appears possible, through acidized 900 mm diameter bore-
holes. An understanding of the degree of interconnection between the Chalk and
Basal Sands and of the causes of changes in quality of recharge water during
storage was shown to be of particular importance to the successful operation of
any recharge scheme using this system. A two-layer numerical groundwater model
of the 800 sq km area and a surface/groundwater simulation model was used to
assist with the design of the 84,000 cu m/d prototype scheme, and also will help
in assessing its efficiency. The models ultimately will be used to manage the
operation of the first stage development, now coming into use.
78:048-011
THREE-DIMENSIONAL MODELING OF GROUNDWATER FLOW SYSTEMS,
Frind, E.G., and Verge, M.J.
Waterloo University, Waterloo, Ontario, Canada N2L 3G1, Department of Earth
Sciences.
Water Resources Research, Vol. 14, No. 5, p 844-856, October, 1978. 15 fig, 3
tab, 30 ref, 15 equ, 1 append.
Descriptors: Groundwater movement, Model studies, Finite element analysis,
Continuity equation, Saturated flow, Unsaturated flow, Groundwater basins, Cost
analysis, Feasibility studies, Computer models.
Practical aspects of three-dimensional (3-D) modeling of groundwater flow systems
were closely examined. A Galerkin finite element model was designed with a view
to providing flexibility, user convenience, and a high degree of efficiency,
qualities which are critical to the success of 3-D modeling of real systems. The
model was based on the general saturated-unsaturated continuity equation. Sev-
eral integration schemes and matrix solvers were compared, and relative costs were
expressed as functions of grid size. Examples presented include a hypothetical
165
-------
system and a real system. Simulation costs were generally found to be reasonable
for grids' of the size encountered with real systems. It was found that the
remaining obstacle to the unified treatment of saturated-unsaturated systems was
that the optimum element sizes required for saturated and unsaturated flow were
not always compatible because of constraints arising from the physical properties
of the materials. In general, however, it appeared that with presently available
tools, 3-D analysis is a practical option.
78:046-012
FINITE ELEMENT METHOD FOR SUBSURFACE HYDROLOGY USING A MIXED EXPLICIT-IMPLICIT
SCHEME,
Narasimhan, T.N., Neuman, S.P., and Witherspoon, P.A.
California University, Berkeley, Lawrence Berkeley Laboratory.
Water Resources Research, Vol. 14, No. 5, p 863-877, October, 1978. 19.fig, 2
tab, 32 ref, 38 equ, 2 append.
Descriptors: Subsurface flow, Finite element analysis, Model studies, Computer
programs, Groundwater movement, Aquifer management, Infiltration, Drainage,
Saturated flow, Unsaturated flow.
The mixed explicit-implicit Galerkin finite element method developed previously
by the authors was shown to be ideally suited for a wide class of problems
arising in subsurface hydrology. These problems include confined saturated
flow, unconfined flow under free surface conditions subject to the Dupuit
assumption, flow in aquifers which are partly confined and partly unconfined,
axisymmetric flow to a well with storage, and flow in saturated-unsaturated
soils. A single computer program, entitled Flump, can handle all of these
problems. The"mixed explicit-implicit solution strategy employed in the program
insured a high level of accuracy and computation efficiency in most cases. Some
of the outstanding features of this solution strategy included an automatic
control of time step size, reclassification of nodes from explicit to implicit
during execution, automatic adjustment of the implicit time-weighting factor,
and the treatment of boundary conditions and source terms as arbitrary functions
of time of the state of the system. Five examples were presented to demonstrate
the versatility and power of this new approach. A purely physical derivation of
the finite element equations which does not rely on the Galerkin formalism was
also included in one of the appendices.
78:046-013
USE OF BOUNDING WELLS TO COUNTERACT THE EFFECTS OF PREEXISTING GROUNDWATER
MOVEMENT,
Whitehead, W.R., and Langhetee, E.J.
Louisiana State University, Baton Rouge, Department of Petroleum Engineering.
Water Resources Research, Vol. 14, No. 2, p 273-280, April, 1978. 8 fig, 5 ref.
Descriptors: *Salaquifers, * Bounding wells, *Water storage, *Injection wells,
*Underground storage/ Groundwater movement, Potentiometric level, Least squares
method, Computer programs.
Underground storage of freshwater in salaquifers is feasible under natural or
man-made conditions. Since recovery efficiency is inversely proportional to
the rate of groundwater flow, reducing the potentiometric gradient reduces
fresh-water loss. This can be done by installing injection and producing
bounding wells. A desired balanced potentiometric level was selected, then the
required rates of the bounding wells were computed using a Fortran IV computer
program which employed a least squares solution. The results of the computer
runs indicated that bounding well flow rates vary directly with the magnitude
of groundwater movement, inversely with the number of bounding well, and
directly with the distance the wells are placed from the boundaries. The only
limitations are that the distance should not be less than 30 degrees of the
radius of the storage area, there should be at least one bounding well in each
quadrant of the storage area, and the sum of the production rates must equal
the sum of the injection rates. The latter limitation ensures that the environ-
mental impact of the system is negligible. A cost comparison chart indicated
that the in-place water cost at which a bounding well system will become economi-
cally attractive decreases as the volume stored increases.
166
-------
78:048-014
SHOULD INTEGRATE PEAK LOAD WITH WATER MANAGEMENT,
Irrigation Age, Management.
Irrigation Age, Vol. 13, No. 1, p 64, September, 1978. 1 fig.
Descriptors: Irrigation practices, Irrigation efficiency, Pumping, Energy,
Sprinkler irrigation, Water reuse, Center pivot systems, Water pressure, Farm
equipment, Fertilizers.
Center pivot irrigators who rely on electricity could save up to $72 million a
year if more "integrated" peak electrical load and water management control
systems were designed. And, the technical knowledge is available. At the same
time, power suppliers would be able to more successfully deal with the problems
of high peak electrical demands. The problem is that short term peaks require
generation and transmission facilities that are under-utilized during much of
the year. Key to success with an integrated approach is that irrigation scheduling
techniques, geared to saving both water and energy, would be used. Savings in
nitrogen, pumping costs and system wear could amount to another $60 million
annually with better water management.
167
-------
SECTION XVIII
WATER QUANTITY MANAGEMENT AND CONTROL
EFFECT ON WATER OF MAN'S NONWATER ACTIVITIES (GROUP 04C)
78:04C-001
TO SOLVE HIGHWAY AND FARM WATER MANAGEMENT PROBLEMS,
Smith, R.L., and Drablos, C.J.W.
Illinois University, Urbana, Department of Agricultural Engineering.
Agricultural Engineering, Vol. 59, No. 2, p 22-24, February, 1978. 4 fig.
Descriptors: Highway effects. Drainage, Drainage water, Soil erosion, Sedimenta-
tion, Legal aspects, Soil conservation. Water management (applied).
Wherever agricultural lands are crossed by highways, drainage interrelationships
between the highway authorities and the adjoining landowners become complex.
Engineering and legal judgment plays an important role in finding the satisfac-
tory solutions to these problems. While it may be permissible to temporarily
obstruct local highways with ponded water, eroded material, and debris, such
conditions should not permanently exist on highways which are subject to heavy,
high-speed traffic. And care must be exercised to reduce adverse effects on
adjoining lands as a result of the highway facilities—for example, the diversion
of water from natural water courses, the interception of subsurface drainage
systems, the obstruction of the natural water flow. This paper discusses the
various aspects of these problems and suggests how the magnitude of most problems
can be reduced which will cause least disruption.
78:04C-002
DRAINAGE PRACTICE IN IMPERIAL VALLEY,
Hermsmeier, L.F.
Imperial Valley Conservation Research Center, United States Department of
Agriculture-Agricultural Research Service, Brawley, California.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 1, p 105-109, February 20, 1978. 1 fig, 7 tab, 10 ref.
(See 78:03C-006)
168
-------
SECTION XIX
WATER QUANTITY MANAGEMENT AND CONTROL
WATERSHED PROTECTION (GROUP 04D)
78:040-001
EROSIONAL REMOVAL OF FALLOUT PLUTONIUM FROM A LARGE MIDWESTERN WATERSHED,
Sprugel, D.G., and Bartelt, G.E.
A onne National Laboratory, Illinois, Radiological and Environmental Research
Division.
Journal of Environmental Quality, Vol. 7, No. 2, p 175-177, April-June, 1978.
2 tab, 28 ref.
Descriptors: *Erosion, *Sediments, *Plutonium, Watersheds (basins), Sampling,
Data processing, Sediment transport, Sorption, Soils, Soil erosion, Suspended
solids.
The Great Miami River at Sidney, Ohio, drains a 1,401-sq km watershed which is
generally flat and predominantly agricultural. Samples of river water
collected over a wide range of flow and sediment loading conditions showed that
the concentrations of 239, 240 Pu in filtered water and suspended sediment were
fairly constant, which means of 0.15 fCi/liter for water and 14 fCi/g for suspended
sediment. Plutonium concentrations in suspended sediment are somewhat higher than
plow-layer soil concentrations, probably due to settling of larger soil particles
in ponds and backwaters in the upper reaches of the river. Annual plutonium
transport from the watershed by erosion averages 1.2 mCi, or 0.9 pCi/sq m, which
is about 0.05% of the total plutonium in the watershed soil. The primary mechanism
for plutonium removal is erosion of small soil particles to which the element is
sorbed.
78:040-002
EROSIONAL TRANSPORT AND DEPOSITION OF PLUTONIUM AND CESIUM IN TWO SMALL MIDWESTERN
WATERSHEDS,
Muller, R.N., Sprugel, D.S., and Kohn, B.
Argonne National Laboratory, Illinois, Radiological and Environmental Research
Division.
Journal of Environmental Quality, Vol. 7, No. 2, p 171-174, April-June, 1978.
4 fig, 1 tab, 18 ref.
Descriptors: *Sediment transport, *Sediment sorting, *Particle size, On-site
investigations, Sediments, Radioisotopes, Plutonium, Cesium, Soils, Clays,
The soils and sediments of two small watersheds and their retaining ponds were
sampled in a study of the erosional transport of plutonium and cesium in mid-
western ecosystems. In a watershed which had been used exclusively for row crops,
no relationship was observed between plutonium content of the sediments and location
in the pond or clay content. In a pasture watershed, sorting of the eroded material
had occurred prior to entry into the pond and also withia the pond. Clay content
in the pasture pond sediments was significantly higher than in the soils of the
surrounding watershed and increased with increasing distance from the inlet.
Plutonium concentration in the sediments was strongly correlated with clay content,
reflecting the higher plutonium content of finer soil particles. Cesium behaved
similarly to plutonium in the soils and sediments of both watersheds. Where sort-
ing occurs, as in the pasture watershed, deposits of fine sediments will contain
higher plutonium and cesiumiconcentrations than in the original surface soil.
78:04D-003
TRANSPORT OF AGRICULTURAL CHEMICALS FROM SMALL UPLAND PIEDMONT WATERSHEDS,
Smith, C.N., Leonard, R.A., Langdale, G.W., and Bailey, G.W.
Environmental Research Laboratory, Athens, Georgia 30605 and Southern Piedmont
Conservation Research Center, Watkinsville, Georgia 30677.
169
-------
Publication No. EPA-600/3-78-056, May, 1978. 364 p, 96 fig, 177 tab, 41 ref,
8 append.
Descriptors: Herbicides, Fertilizers, Pesticides, Surface water runoff.
Data were collected from four small watersheds (1.3 to 2.7 ha) located in the
Southern Piedmont region. Two watersheds were managed without conservation
measures; the other two watersheds were parallel-terraced and included grassed
waterways for soil erosion control. Total losses of applied herbicides were
affected by the occurrence of runoff in close proximity to application date,
mode of application, and persistence in the soil runoff zone. Most of the
total annual losses by runoff were in the first three runoff events for all
compounds except paraquat. Runoff of trifluralin was very low {0.1 to 0.3% of
the annual application). Total runoff losses of other herbicides were commonly
less than 1.0% except when runoff occurred shortly after application. Sediment
yield from terraced watersheds was significantly less than from watersheds
managed without terraces. Except for paraquat, however, pesticide yields in
runoff were not reduced in proportion to sediment reduction because solution
transport was the major mode of loss for the soluble herbicide phase. Annual
runoff losses of soluble plant nutrients were 5.0 and 1.3 kg/ha for chloride
and nitrate, respectively. Losses of soluble phosphorus from both watersheds
were very low, about 380 g/ha.
78:040-004
EFFECT OF MULCHING ON SEDIMENT IN RUNOFF FROM SIMULATED RAINFALL,
singer, M.J., and Blackard, J.
California University, Davis, Department of Land, Air, and Water Resources.
Soil Science Society of America Journal, Vol. 42, No. 3, p 481-486, May-June,
1978. 2 fig, 2 tab, 22 ref.
Descriptors: *Erosion control, *Mulching, *Simulated rainfall, Laboratory tests,
Erosion, Soil erosion, Litter, Leaves, Data processing, Sediments.
Simulated rainfall was used to test the relationship between sediment in runoff
and percent of the soil that was mulch covered. Oak leaves, redwood litter, and
oat straw were used as mulches on a 0.37 sq m plot of Auburn (loamy, mixed,
thermic, Ruptic-Lithic Xerochrepts) surface soil at a 9% slope. Cover percentage
was related to sediment in surface runoff by a parabolic relationship. The
relationship between redwood and oak covers and sediment in runoff was not
significantly different, but both were significantly different from oat straw.
-Cover shape or distribution of inter-cover space appears to be important in
affecting sediment loss. Runoff volume was reduced significantly by high cover
levels which protected the soil from sealing and helped maintain a high infiltra-
tion rate.
78:040-005
A SEDIMENT GRAPH MODEL BASED ON AN INSTANTANEOUS UNIT SEDIMENT GRAPH,
Williams, J.R.
Agricultural Research Service, Temple, Texas, Grassland Forage Research Center.
Water Resources Research, Vol. 14, No. 4, p 659-664, August, 1978. 2 fig, 3 tab,
10 ref.
Descriptors: *Sedimentation rates, *Erosion, *Texas, *Storm runoff, -*Model studies*
Mathematical models, Sediments, Rainfall, Watersheds (basins), Land use.
A model was developed for predicting sediment graphs from agricultural watersheds.
Storm sediment graphs were predicted by convolving source runoff with an instan-
taneous unit sediment graph (IUSG). The IUSG is the distribution of sediment from
an instantaneous burst of rainfall producing one unit of runoff. The IUSG is the
product of an instantaneous unit hydrograph and the sediment concentration dis-
tribution. Initial sediment concentration of IUSG was assumed to vary linearly
with source runoff volume. A sediment-routing function, based on travel time and
sediment particle size, was used to predict the sediment concentration distribution.
Tests with 50 storms from 5 watersheds showed that the model is applicable to
agricultural watersheds in the Texas blacklands. It should be useful in designing
reservoirs or in water quality-modeling problems.
170
-------
78:040-006
FAILURE SEQUENCE OF GULLY HEADWALLS IN WESTERN IOWA,
Bradford, J.M., Piest, R.F. , and Sportier, R.G.
Missouri Agricultural Experimental Station,.Columbia.
Soil Science Society of America Journal, Vol. 42, No. 2, p 323-328, March, 1978
6 fig, 1 tab, 20 ref.
Descriptors: *Erosion, *Iowa, *Missouri, *South Carolina, *Soil morphology,
Soil strength, Sedimentation, Slope stability, Gully erosion, Loess.
A characterization of the failure sequence of gully headwalls and banks is
necessary to predict gully erosion rates and to develop controls. A model was
given for the sequential nature of gully growth in the thick loessial area of
western Iowa. The failure sequence includes a popout or alcove failure near the
toe of a near-vertical wall; columnar sloughing of the overhanging material;
and finally, the transport of the eroded material downstream. The initiating
failure at the base of the wall is a result of weakening of the soil material
by wetting. The gully bank failure sequence and geometry in the western Iowa
loess region were compared to gully erosion studies in the glacial drift region
of northwestern Missouri and in the Piedmont of South Carolina.
78:040-007
CONTROLLING DUST IN THE MOHAVE VALLEY,
Halderman, A.D.
Arizona Agricultural Experiment Station, Tucson.
Agricultural Engineering, Vol. 59, No. 2, p 25-26, February, 1978.
Descriptors: *Soil management, *Dust, *Air pollution, *Wind erosion, *Arizona,
*Colorado River, *Mohave Valley (Arizona)', Soil erosion, Land reclamation, Grading.
Land grading to adapt Indian lands for irrigated farming along the Colorado River
in Mohave County, Arizona, has created dust problems severe enough to close
schools and alarm health authorities. Between the removal of vegetation and the
establishment of a crop, the land is particularly vulnerable to blowing. Members
of the University of Arizona Department of Soils, Water and Engineering have
offered several recommendations to alleviate the problem: Limiting the amount
of land graded at any one time, coordinating clearing operations with prevailing
winds to avoid blowing toward urban and commercial centers, digging wells to wet
the land after brush removal and before grading, and the establishment of crops
as soon as possible after grading. These recommendations can be adapted to local
conditions and are presently being implemented.
78:040-008
MAXIMUM NONEROSIVE FURROW IRRIGATION STREAM SIZE,
Hamad, S.N., and Stringham, G.E.
Utah State University, Logan, Department of Agricultural and Irrigation Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR3, Proceedings Paper 14021, p 275-281, September,
1978. 3 fig, 1 tab, 13 ref, 2 append.
Descriptors: *Furrow irrigation, *Erosion, *Irrigation ditches, Size, Slopes,
Slope stability, Channels, Channel erosion. Channel flow, Irrigation, Surface
irrigation, Soils, Water pollution, Sediments.
A technique was presented to predict maximum nonerosive irrigation stream size for
furrows as a function of soil type and bed slope. Data for different soils and
field conditions were analyzed to estimate the coefficients of a prediction equa-
tion. A table giving the estimated coefficients for each soil type was given.
171
-------
SECTION XX
WATER QUALITY MANAGEMENT AND PROTECTION
IDENTIFICATION OF POLLUTANTS (GROUP 05A)
78:05A-001
IMPACT OF LAND USE ON GROUNDWATER QUALITY IN THE GRAND TRAVERSE BAY REGION OF
MICHIGAN,
Rajagopal, R.
Duke University, Durham, North Carolina, School of Forestry and Environmental
Studies.
Journal of Environmental Quality, Vol. 7, No. 1, p 93-98, January-March, 1978.
6 fig, 5 tab, 17 ref.
Descriptors: *Groundwater, *Water quality, *Land use, *Michigan, *Grand
Traverse Bay Region (Michigan), Surveys, Sampling, Pollutants, Water pollution,
Path of pollutants.
Investigations in townships surrounding the Grand Traverse Bay of Michigan
showed an identifiable geographic relationship between groundwater quality and
land use. Wells averaging 32 m deep in thinly populated areas measured an
average of 3.75 ppm nitrate-N, indicating the effect of prolonged years of
fertilizer application. Wells averaging 19 m deep in predominantly residential
areas had an average of 1.31 ppm nitrate-N, indicating possible contamination
from septic tank effluents. An average of 0.18 ppm of ammonia-N was detected in
marshy wetlands. An analysis of temporal variations in groundwater quality with
reference to precipitation, streamflow, and a trend component provided high as
well as low R sq (0.92 to 0.12;R sq = square of the multiple correlation coeffi-
cient) producing regression models, indicating the'effect of site specific con-
ditions. A year-long observation of a sample well (43 m deep) surrounded by
cherry orchards has an average of 18.25 ppm nitrate-N in a range of 13.09 to
20.64 ppm, almost double the standard considered safe for human consumption.
Ammonia-N and chloride measurements from a shallow well (12.5 m deep), sur-
rounded by residential and commercial activities, showed synchronized variations
over a year (correlation coefficient r = 0.75, significant at 1% level), sug-
gesting the existence of a common source of contamination. In summary, it was
reiterated that the analysis of groundwater quality problems requires a differ-
ent philosophical approach from the approaches used for water quantity and
surface water quality modeling.
78:05A-002
ARSENIC POLLUTION FROM UNDERDRAINAGE AND RUNOFF FROM GOLF GREENS,
Duble, R.L., Thomas, J.C., and Brown, K.W.
Texas A & M University, College Station, Department of Soil and Crop Sciences.
Agronomy Journal, Vol. 70, No. 1, p 71-74, January-February, 1978. 4 fig, 6 ref.
Descriptors: Golf courses, Arsenicals (pesticides), Pollutants, Leachate,
Runoff, Return flows, Sprinkler irrigation, Turf grasses.
A field study was conducted using four lysimeters (each 3 m by 3 m) containing a
Tabor sandy loam soil (Udertic Paleustales) and 16 lysimeters containing differ-
ent sand-soil-peat mixtures, each equipped with a gravel underdrainage system.
Bermudagrass (Cynodon dactylan L.) turf was maintained at a height of approxi-
mately 1 cm of water daily. Tricalcium arsenate was applied on two dates at a
rate of 88 kg ha"1. Arsenic was found in significant concentrations in both
drainage and runoff from lysimeters. Particularly high concentration (8 ppm As)
were found in the drainage from plots previously cored for soil samples. Con-
centrations of As in the runoff were as great as 14 ppm when a heavy rain
occurred shortly after application of Ca3(As04)2. Drainage from the plots
172
-------
typically contained 1 to 3 ppm and decreased slowly with time. Arsenic concen-
trations of 0.8 ppm were still found in the drainage 115 days after application.
Concentrations of As in the runoff and drainage from all the plots exceeded
acceptable limits for irrigation water established by the U.S. Public Health
Service.
78:05A-003
ATRAZINE MOBILITY IN TWO SOILS UNDER CONVENTIONAL TILLAGE,
Hall, J.K., and Hartwig, N.L.
Pennsylvania Agricultural Experiment Station, University Park, Soil Chemistry
and Weed Science.
Journal of Environmental Quality, Vol. 7, No. 1, p 63-68, January-March, 1978..
7 tab, 20 ref.
Descriptors: Pesticides, Herbicides, Leaching, Lysimeters, Bioassay, Soil
contamination, Pennsylvania.
Atrazine mobility was studied in two different Pennsylvania soils under conven-
tional tillage. Atrazine mobility,-dissipation rate, and residual activity were
evaluated by chemical analysis and oat bioassay of soil cores sampled at 15-cm
increments to 122 cm and from chemical analysis of suction lysimeter leachates.
It appeared from this study that application of atrazine to fine-textured, con-
ventionally tilled soils at rates ranging from-1.0 to 4.5 kg/ha would not seriously
affect groundwater supplies through contamination by internal soil damage.
78:05A-004
NITRATE ACCUMULATION IN SOILS AND LOSS IN TILE DRAINAGE FOLLOWING NITROGEN
APPLICATIONS TO CONTINUOUS CORN,
Cast, R.G., Nelson, W.W., and Randall, G.W.
Minnesota University, St. Paul, Minnesota Agricultural Experiment Station.
Journal of Environmental Quality, Vol. 7, No. 2, p 258-261, April-June, 1978.
1 fig, 4 tab, 9 ref.
Descriptors: Nutrient removal, Denitrification, Nitrates, Tile drainage, Water
pollution, Sweet corn, Minnesota.
Nitrate-N concentration in tile water, loss from tile lines, and accumulation in
soil profiles were determined following each of three annual applications of 20,
112, 224, and 448 kg N/ha to continuous corn (Zea mays L.) grown on a Webster
clay loam (Typic Haplaguoll) in southern Minnesota. Plots were isolated to a
depth of 1.8 m with plastic to allow an accurate assessment of the area drained.
There was relatively little increased N03-N accumulation in the soil profile or
loss from tile lines at the recommended application rate of 112 kg N/ha compared
to that for the check treatment. Nitrate-N losses through tile lines in 1975
(after 3 years treatment) were 19, 25, 59, and 120 kg/ha for the 20, 112, 224,
and 448 kg N/ha applications, respectively, which had N03-N accumulations in the
0-3 m soil profiles of 54, 100, 426, and 770 kg N03-N/ha. Maximum N03-N accumu-
lation in the soil profiles occurred at a depth of about 1 m with little evidence
of movement below about 2.2 m.
78:05A-005
EFFECTS OF TRACE ELEMENTS ON NITRIFICATION IN SOILS,
Liang, C.N., and Tabatabai, M.A.
Iowa State University, Ames, Department of Agronomy.
Journal of Environmental Quality, Vol. 7, No. 2, p 291-293, April-June, 1978.
3 tab, 15 ref.
Descriptors: Nitrification, Inhibitors, Nitrates, Nitrites, Trace elements,
Heavy metals, Pollutants.
Studies to evaluate the effects on nitrification of 19 trace elements showed that
all these elements inhibited nitrification of NH4(+)-N added to soils. Results
showed that the relative effectiveness of the trace elements in inhibition of
nitrification depends on the soils. When the trace elements were compared to
using 5 micromoles/g of soil, Ag(I), Hg{II), Cd(II), Ni (II), As(III), Cr(III),
173
-------
B(III), Al(III), Se(IV), and Mo(VI) were the most effective inhibitors (average
inhibition >50%, and Mn(II) and Pb(II) the least effective (average inhibition
<25%) inhibitors. The average inhibition by the elements Co(II), Cu(II),
Sn(II), Fe(II), Zn(II), Fe(III), V(IV), and W(VI) ranged from 33% with W(VI) to
49% with Fe(III). Silver(I), Ni(II), Co(II), Zn(II), Mn(II), Pb(II), As(III),
B(III), Fe(III), As(V), Mo(VI), and W(VI) inhibited Nitrobacter, causing accumu-
lation of N02(-)-N in one of the soils used.
78:05A-006
A METHOD FOR PARAMETER SENSITIVITY ANALYSIS IN DIFFERENTIAL EQUATION MODELS,
Kohberger, R.C., Scavia, D., and Wilkinson, J.W.
Albany Medical College, New York, Division of Computer Science.
Water Resources Research, Vol. 14, No. 1, p 25-29, February, 1978. 4 fig, 4
tab, 13 ref, 9 equ.
Descriptors: Mathematical models, Least squares method, Analytical techniques,
Probability.
A numeric method for analyzing global parameter sensitivity about a fixed point
in parameter space for differential equation models is presented. The method is
suitable for large-scale, multiresponse systems which may not be in steady
state. By using a quadratic model, the relationship between several global
response characteristics and parameter perturbations is examined. Sensitivity
relationships are defined with both backward elimination regression model selec-
tion procedures and eigenvalue-eigenvector analyses. An example of the method
is given using an ecosystem model consisting of 14 coupled differential equa-
tions.
78:05A-007
DESIGN CONSIDERATIONS FOR AMBIENT STREAM QUALITY MONITORING,
Lettenmaier, D.P.
Washington University, Seattle, Department of Civil Engineering.
Water Resources Bulletin, Vol. 14, No. 4, p 884-902, August, 1978. 3 fig, 5
tab, 21 ref.
Descriptors: *Monitoring, *Water quality, *Network design, *Mathematical
models, Networks, Sampling, Streams, Pollutants, Statistics, Statistical models.
Existing ambient water quality monitoring programs have resulted in data which
are often unsuitable for assessment of water quality trends. A primary concern
in designing a stream quality monitoring network is the selection of a temporal
sampling strategy. It is extremely important that data for trend assessment be
collected uniformly in time. Greatly superior trend detection power results for
such a strategy as compared to stratified sampling strategies. In general, it
is desirable that sampling frequencies be at least monthly but not greater than
biweekly; higher sampling frequencies usually result in little additional infor-
mation. An upper limit on trend detectability exists such that for both five
and ten year base periods it is often impossible to detect trends in time series
where the ratio of the trend magnitude to time series standard deviation is less
than about 0.5. For the same record lengths, trends in records with trend to
standard deviation ratios greater than about one usually can be detected with
very high power when a uniform sampling strategy is followed.
78:05A-008
SAMPLING FREQUENCY FOR RIVER QUALITY MONITORING,
Sanders, T.G., and Adrian, D.D.
Colorado State University, Fort Collins, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 4, p 569-576, 1978. 5 fig, 3 tab, 25 ref.
Descriptors: *Sampling, *Monitoring, *Water quality, *Connecticut River,
Control, Water analysis, Statistical methods, Chemical analysis, River basins,
River flow.
Sampling frequency for a water quality monitoring network is presented, and for
illustrative purposes the criterion is applied to the Massachusetts portion of
the Connecticut River basin. The proposed frequency criterion is based upon the
174
-------
assumption that the primary objectives of future river quality monitoring net-
works are the determination of ambient water quality conditions and an assess-
ment of yearly trends rather than detection, of stream or effluent standards
violations. The sampling frequency criterion is derived as a function of the
random variability of the river flow. The criterion is specifically related to
the magnitude of the expected half width of the confidence interval of the mean
of the random component of the annual statistic--mean log river flow. The
appropriate sampling intervals (at each sampling station within the river basin)
are determined by specifying equality of this confidence interval half width
which insures a uniform reliability of the annual statistic. '
78:05A-009
FIELD MEASUREMENT OF DENITRIFICATION,
Rolston, D.E., and Broadbent, F.E.
California University, Davis, Department of Land, Air and Water Resources
Report No. EPA-600/2-77-233, November, 1977. 75 p, 40 fig, 15 tab, 13 ref.
Descriptors: *Denitrification, *Soil moisture, *Vegetation effects, *Gas flux,
Irrigation, Nitrates, Nitrites, Nitrogen compounds, Soil environment, Soil
management.
Denitrification from a Yolo loam field profile was studied in relation to the
influence of soil-water content, organic carbon source, and temperature. Field
plots were instrumented with soil atmosphere samplers, soil solution samplers,
and tensiometers. The two soil-water pressure treatments were applied in top-
soil. Three levels of soil carbon were studied by evaluating plots cropped with
ryegrass, uncropped plots, and plots amended with manure. Experiments were
conducted at soil temperatures of 8 and 23C. Fertilizer was applied as KN03
enriched-with N15. The flux of volatile gases at the soil surface was measured
from the accumulation of N20 and nitrogen gas isotopes beneath an airtight cover
placed over the soil surface. Denitrification at 23C ranged from 73% of the
fertilizer nitrogen for the manure treatment to 1% for the uncropped treatment.
At 8C, denitrification ranged from 11% for the manure treatment to zero for
uncropped plots. The nitrite flux at the soil surface varied between 5 and 26%
of total denitrification. The results demonstrated that denitrification of soil
can occur at high rates (highest soon after application of N03(-) fertilizer to
wet soil), and that the presence of a crop root system has a large positive
influence on denitrification.
78:05A-010
CARBON CONTENTS AND SOURCES IN GROUNDWATERS OF THE CENTRAL PLATTE REGION IN
NEBRASKA,
Spalding, R.F., Gormly, J.R., and Nash, K.G.
Nebraska University, Lincoln, Conservation and Survey Division.
Journal of Environmental Quality, Vol. 7, No. 3, p 428-434, July-September, 1978.
2 fig, 3 tab, 23 ref.
Descriptors: *Groundwater, *Dissolved oxygen, *Dissolved organic carbon,
*Carbon, *Nebraska, *Platte River (Nebraska), *Alkalinity, Water chemistry,
Water wells, Land use.
Fifty-one groundwater samples collected in a losing reach of the Platte River
were analyzed for alkalinity, dissolved oxygen (DO), and'dissolved organic carbon
(DOC). Ranges in concentrations were 24.8 to 109 mg/liter, .0 to 5.5 rag/liter,
and 0.5 to 4.8 mg/liter for organic carbon, DO, DOC, respectively. The concen-
trations of these constituents are primarily associated with land use and well
depth. Carbon isotope fractionation can be useful in determining sources of
organic carbon to the groundwater.
78:05A-011
AN IMPROVED SOIL-SAMPLING PROCEDURE FOR THE PREDICTION OF DISSOLVED INORGANIC
PHOSPHATE CONCENTRATIONS IN SURFACE RUNOFF FROM PASTURE,
Sharpley, A.N., Syers, J.K., and Tillman, R.W.
Massey University, Palmerston North, New Zealand, Agricultural and Horticultural
Sciences.
175
-------
Journal of Environmental Quality, Vol. 7, No. 3, p 455-456, 1978.
3 ref.
3 fig, 1 tab,
Descriptors: *Phosphates, *Agricultural runoff, *Soil analysis, *Sampling,
*Phosphorus compounds, *Dissolved inorganic phosphates, *Phosphate transport,
*Soil sampling procedure, *Surface-runoff plots, Soil sampling.
Linear relationships were obtained between the mean concentration of dissolved
inorganic phosphate (DIP) in each of several surface-runoff events and the
amounts of inorganic P extracted by 0.1M NaCl from the top 1 cm of soil sampled
prior to the event. These relationships were similar for both unfertilized and
fertilized, undrained pasture. This contrasted with the data obtained in the
previous year for the same surface-runoff plots, receiving the same treatments,
where markedly different linear relationships were obtained using a 0.5 cm soil-
sampling depth. The modified soil-sampling procedure provides more generally
applicable method of predicting the concentration of DIP in surface runoff from
pastures of widely differing P status.
78:05A-012
PRECIPITATION AND THROUGHFALL CHEMISTRY IN THE SAN FRANCISCO BAY AREA,
McColl, J.G., and Bush, D.S.
California University, Berkeley, Department of Soils and Plant Nutrition.
Journal of Environmental Quality, Vol. 7, No. 3, p 352-357, July-September,
1978. 3 fig, 1 tab, 36 ref.
Descriptors: Precipitation (atmospheric), Throughfall, Rainfall, Chemical
analysis, Forest soils, Air pollution, Nutrients, Acidity, California.
At Berkeley, California, main ionic constituents of bulk precipitation during
the wet season of 1974-1975 were S04(2-), Cl'(-) , HC03(-), Na(+) , and Ca(2+) ,
and mean H(+) concentration was 10.7 ± 1.5 microequivalents/liter (pH 5.0).
Although S04(2-) comprised 50% of the anions in bulk precipitation, H(+) con-
centration had the highest correlation with N03(-). Impacted air pollutants
accumulated on tree leaves between major rainstorms. Atmospheric N and S were
correlated with N03(-) and S04(2-) in bulk precipitation and leafwash in a
Eucalyptus globulus forest. Ionic composition of bulk precipitation resembled
that of surface-soil solution in an adjoining, recently clear-cut area.
78:05A-013
METABOLISM OF NITROPHENOLS IN FLOODED SOILS,
Sudhakar-Barik, and Sethunathan, N.
Central Rice Research Institute, Cuttack-753006, India, Laboratory of Soil
Microbiology.
Journal of Environmental Quality, Vol. 7, No. 3, p 349-352, July-September,
1978. 4 tab, 12 ref.
(See 78:02K-049)
78:05A-014
BIOLOGICAL HYDROLYSIS OF PARATHION IN NATURAL ECOSYSTEMS,
Sudhakar-Barik, and Sethunathan, N.
Central Rice Research Institute, Cuttack-753006, India, Laboratory of Soil
Microbiology.
Journal of Environmental Quality, Vol. 7,-No. 3, p 346-348, July-September,
1978. 5 tab, 11 ref.
(See 78:02K-053)
78:05A-015
SOME PROPERTIES OF THE GEOMETRIC MEAN AND ITS USE IN HATER QUALITY STANDARDS,
Landwehr, J.M.
Geological Survey, Reston, Virginia, Water Resources Division.
Water Resources Research, Vol. 14, No. 3, p 467-473, June, 1978. 4 fig, 7 tab,
17 ref.
176
-------
Descriptors: *Water quality standards, *Coliforms, *Water analysis, *Analytical
techniques, *Statistical methods, *Swimming facilities, *Geometric mean, Proper-
ties, Sampling, Evaluation,
The geometric mean is often used to express acceptable levels of fecal coliform
counts in Federal and State water quality criteria or standards. The expected
value of the geometric mean is shown to be a function of the sample size and to
be very sensitive to the skew as well as to the form of the underlying distri-
bution function. Implications of these findings are discussed with regard to
standards. In particular, it is noted that great care must be taken in specify-
ing the minimal sample size to be used.
78:05A-016
ESTIMATION AND MANAGEMENT OF THE CONTRIBUTION BY MANURE FROM LIVESTOCK IN THE
ONTARIO GREAT LAKES BASIN TO THE PHOSPHORUS LOADING OF THE GREAT LAKES,
Draper, D.W., Robinson, J.B., and Coote, D.R. ,_,„.,
Guelph University, Guelph, Ontario, Canada, Department of Environmental Biology.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p
159-174. 2 fig, 4 tab, 39 ref, 3 equ.
Descriptors: Agricultural runoff. Nutrient removal, Phosphorus, Livestock, Great
Lakes, Water pollution, Water quality, Feed lots.
As part of the work of the International Reference Group on Great Lakes Pollution
from Land Use Activities (PLUARG) a simple model has been developed for estimating
contributions of total phosphorus to Great Lakes tributary loading originating
with livestock manure produced in the Basin. Total loads attributable to live-
stock sources and a range of probable unit loads on a per animal unit per year
basis were calculated.
PHOSPHORUS—A POTENTIAL NONPOINT SOURCE POLLUTION PROBLEM IN THE LAND AREAS
RECEIVING LONG-TERM APPLICATION OF WASTES,
Reddy, K.R., Khaleel, R. , Overcash, M.R. , and Westerman, P.W.
North Carolina State University, Raleigh, Department of Biological and
P?oceedings1ofntheei9789Cornell Agricultural Waste Management conference, p 193-
211. 7 fig, 7 tab, 29 ref, 3 equ.
Descriptors: Wastes, Phosphorus, Water quality, Runoff, Water pollution sources,
Nutrients, Water pollution.
The main objective of this work was to describe the P behavior in the soils
treated with wastes and their relationship to the surface water quality. The
resJlS obtained from these studies indicated that application of animal wastes
decreased P sorption capacity of the soil and increased P concentration in the
soil solution, thus increasing the equilibrium P concentration (EPC) , at which
no net adsorption or desorption takes place. A s*?f **C*"h ?J Js £ Scl T
observed between EPC values and P extracted with dilute acid (0.05 N HC1 +
0.025 N H2S04). Continuous application of wastes with high loading rates of P
resulted in P movement into deeper layers. Transport of ^^Jherinto deeper
soil layers or in the surface runoff water was dependent on the availability
or soluSle P in the soil surface at the time of rainfall event. Simple equations
were developed to describe the availability of P at the soil surface, and the
processes controlling P availability were also taken into consideration.
ANIMAL'MANURE MOVEMENT IN WINTER RUNOFF FOR DIFFERENT SURFACE CONDITIONS,
Thompson, D,B.. Loudon, T.L., and Gerrish, J.B. _ *„„',, •*>-*„„
Minnesota University, St. Paul, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p
145-157. 1 fig, 4 tab, 16 ref.
Descriptors: Agricultural runoff, Water quality, Water pollution. Nutrient
removal, Runoff, Return flow, Water quality control. Chemical oxygen demand,
Chemical degradation.
177
-------
This experiment was designed to observe the impact of selected management
practices on winter runoff quality. The effects of various surface conditions
and buffer zones on runoff quality associated with land application of animal
waste on frozen, snow-covered soil were evaluated.- Three different surface
covers with two lengths of buffer zone were compared as management practices
which could be utilized for the reduction of nutrients contained in runoff from
land application areas. The surface conditions used for the plots were corn
stalk stubble with rows running across the slope, corn stalk stubble which had
been fall disked across the slope, and established orchard grass. Runoff
samples were analyzed for concentrations of ammonia, total Kjeldahl nitrogen,
total phosphorus, chemical oxygen demand (COD), total and volatile solids.
Twelve plots were established on a Hillsdale sandy loam soil with a 3.5% slope.
The plots were 3 x 58 meters with the upslope 3 x 24 meters receviing the
manure application. Four plots were used for each surface conditions, two control
and two spread with 62.7 M ton/ha of fresh dairy manure. The results of the
experiment have been reported with discussion.
78:05A-019
ESTIMATING PHOSPHORUS LOADING FROM LIVESTOCK WASTES: SOME WISCONSIN RESULTS,
Moore, I.e., Madison, F.W., and Schneider, R.R.
Wisconsin University, Madison, Water Resources Center.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 175-
192. 3 fig, 7 tab, 17 ref.
Descriptors: Wastes, Water pollution. Water pollution control, Livestock, Water
quality control, Phosphorus, Agricultural watersheds, Pollutant identification,
Agricultural runoff, Analytical techniques.
A description of an approach used to estimate phosphorus loading to the Great
Lakes from livestock wastes in Wisconsin was presented. The results reported
represent minimum annual loadings of total phosphorus to Lake Superior and Lake
Michigan from areas of Wisconsin in these drainage basins. Estimates of the
total phosphorus reaching surface waters from manure sources in the rest of the
state were made on a per animal unit basis. The analytical techniques employed
were reported separately. The emphasis was placed on the data requirements of
the analysis. A key assumption of the methodology is that phosphorus in surface
runoff will be linearly attentuated as long as the overland flow remains un-
channelized. Thus, data on the location of barnlots and manure-spread fields
with relation to surface features capable of channelizing flow were considered
to be of primary importance. Problems encountered in determining this distribu-
tion of animal concentrations with respect to channels over a large and physio-
graphical diverse region were discussed.
78:05A-020
NUTRIENT AND PESTICIDE MOVEMENT FROM FIELD TO STREAM: A FIELD STUDY,
Baker, J.L., Johnson, H.P., Borcherding, M.A., and Payne, W.R.
Iowa State University, Ames, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 213-
245. 10 fig, 7 tab, 21 ref.
Descriptors: Nutrient removal, Pesticide removal, Agricultural runoff, Hydrologic
aspects, Nitrogen, Phosphorus, Water quality, Water pollution. Mathematical
models, Sedimentation.
The general .objective of this field study is to provide a better understanding of
the relationships between management farm systems and stream water quality and to
enable analysis of such systems using mathematical models. Specific objectives
are (1) to collect data to refine an Agricultural Runoff Model proposed by U.S.
Environmental Protection Agency; (2) to relate runoff and soil-erosion nutrient
{nitrogen and phosphorus) losses to hydrologic factors as altered by land manage-
ment; (3) to relate losses of pesticides in runoff to pesticide properties and
to hydrologic and management factors; and (4) to relate sedimentation to hydrologic
and management factors. In this paper, the study was described and initial results
were presented.
178
-------
78:05A-021
SEARCH FOR NITRIFYING AGENTS IN WATER AND SOILS AS SOURCES OF NITRATES IN
SURFACE WATER,
Phillips, N.A., and Todd, R.L.
Georgia University, Athens, Department of Agronomy and Institute of Ecology.
Technical Completion Report, USDI/OWRT Project No. A-066-GA, February, 1978.
89 p, 9 tab, 61 ref, 1 append.
Descriptors: Nitrogen, Nitrates, Surface waters, Nitrification, Small watersheds,
Forest watersheds, Agriculture, Land use. Soil bacteria, Water quality.
The soil and surrounding water of seventeen diverse types of watersheds were
analyzed over a one-year sampling period for a variety of parameters. Terrestrial
nitrifying populations were quantified. Concentrations of ammonia, nitrate,
and total nitrogen and pH were measured from soil extracts. The water was
analyzed for concentrations of nitrate, ammonia, and seven'selected cations. The
terrestrial nitrifying bacteria were found to be positively correlated to nitrate
and cation loss from so-called "natural" systems, i.e., ones that were not ferti-
lized. Those heavily managed (fertilized) systems showed no relationship bet-
ween nitrate and cation discharge and numbers of nitrifying bacteria. The average
concentration of nitrate-nitrogen lost from natural systems was 0.07 mg/1 over
the year. That lost from the fertilized systems averaged 0.47 mg/1, approximately
a 7-fold increase. Similiar relationships were found for average cation discharge.
78:05A-022
SOIL WATER CONTENT AND TEMPERATURE AS FACTORS IN THE VOLATILE LOSS OF APPLIED
MERCURY (II) FROM SOILS,
Landa, E.R.
Oregon State University, Corvallis, Departments of Soil Science and Agricultural
Chemistry.
Soil Science, Vol. 126, No. 1, p 44-48, July, 1978. .2 fig, 1 tab, 16 ref.
Descriptors: Mercury, Volatility, Soil contamination, Moisture content, Soil
temperature, Pollutants, Pollutant identification, Water pollution sources.
Five surface soils from southeastern Montana were studied to determine the effects
of soil water content and temperature on the volatile loss of applied divalent
inorganic mercury. Soils were amended to 1 ppm Hg as 203 Hg-Hg(NO3)2. The
water content studies involved soil samples at room temperature (18-25CC), either
allowed to air-dry or maintained near the 1/3-bar or the 80% saturated moisture
levels. The temperature studies involved samples at the 1/3-bar moisture level
maintained at either 10°C, room temperature, or 35°C. Residual Hg content was
monitored for 5-7 weeks. Hg losses were higher at the 1/3-bar moisture content
than at air-dryness or 80% saturation. At 35°C the initial Hg loss rate was
accelerated with respect to room temperature, while at 10°C, losses were con-
siderably reduced.
179
-------
SECTION XXI
WATER QUALITY MANAGEMENT AND PROTECTION
SOURCES AND FATE OF POLLUTION (GROUP 05B)
78:053-001
NITROGEN FERTILIZER AND NITRATE CONCENTRATIONS IN TRIBUTARIES OF THE UPPER
SANGAMON RIVER IN ILLINOIS,
Klepper, R.
Washington University, St. Louis, Missouri, Center for the Biology of Natural
Systems.
Journal of Environmental Quality, Vol. 7, No. 1, p 13-22, January-March,
1978. 1 fig, 9 tab, 12 ref, 1 append.
Descriptors: *Nitrates, *Water pollution, *Fertilizers, *Farm management,
*Illinois, Regression analysis, Drainage, Tributaries, Soybeans, Data
collections.
Cross section multiple regressions were used to test the importance of nitrogen
fertilizer use for variations in the nitrate nitrogen concentrations in 16 small
tributaries of the Sangamon River in east central Illinois. Data were collected
and regressions were run for two years, 1974 and 1975. Nitrate nitrogen con-
centrations in the spring of each year were regressed on estimated nitrogen
fertilizer use per hectare of watershed in the previous crop or calendar year and
on variables representing other aspects of agronomic practice and hydrologic
features. The fertilizer data were collected by surveying approximately 300
farmers. Nitrate nitrogen concentrations were measured at four-week intervals.
The regression results are not clear-cut but lend support to nitrogen fertilizer
use as an important explanatory variable for varia-tions in nitrate nitrogen
concentrations.
78:058-002
POLLUTANT CONTRIBUTIONS FROM IRRIGATION SURFACE RETURN FLOWS,
Miller, W.W., Guitjens, J.C., Mahannah, C.N., and Joung, H.M.
Max C. Fleischmann College of Agriculture, Reno, Nevada.
Journal of Environmental Quality, Vol. 7, No. 1, p 35-40, January-March, 1978.
2 fig, 5 tab, 10 ref.
Descriptors: Water pollution effects, *Water quality control, *Water pollution
sources, *Flood irrigation, *Nevada, *Return flow, Water sampling, On-site
investigations, Surface-groundwater relationships, Oxidation.
Four study/sites, located in the Carson River Basin, Nevada, containing approxi-
mately 500,000 acres irrigated by surface flooding, were selected for a two-year
investigation of causes and sources of irrigation surface return flow pollution
and the interrelationships among pollution components. Irrigation applications
and surface return flows were metered, net applied water was computed, and
volume of infiltrated water was determined, based on water sampling and 'laboratory
analysis of DO, BOD, TDS, NO3, -N, TN, PO4-P, and TP. Phosphate content was
determined, via the persulfate digestion method. Filterable orthophosphate was
determined by the ascorbic acid method. Study conclusions suggest: (1) BOD,
arid to a less extent, P4-P, are identified as major pollutants; (2) significant
decrease in DO is noted as water moves from head to tail; (3) diffuse subsurface
return flows appear to be sources of certain pollutants for surface water; and
(4) water quality differences may be attributed in part to changes in water
quantities/ suggesting the need for further investigation.
78:058-003
EFFECTS OF SOIL, COVER CROP, AND NUTRIENT SOURCE ON AMOUNTS AND FORMS OF PHOSPHORUS
MOVEMENT UNDER SIMULATED RAINFALL CONDITIONS,
180
-------
Reddy,\G.Y., McLean, E.O., Hoyt, G.D., and Logan, T.J.
Ohio Agricultural Research and Development Center, Wooster.
Journal of Environmental Quality, Vol. 7, No. 1, p 50-54, January-March, 1978.
1 fig, 4 tab, 20 ref.
Descriptors: *Phosphorus, *Runoff, *Sediraents, laboratory tests, *Path of
pollutants, Erosion, Soil erosion, Soils, Leachate, Chemical analysis.
Three soils (Toledo silty clay, Rossmoyne silt loam, and Wauseon sandy loam)
in greenhouse microplots were treated with chemical, chemical + straw, and
manure sources of N, P, and K, were cropped or left bare, and were subjected
to simulated rainfall. Phosphorus moving in runoff sediments, runoff solution,
and leachate was measured. Most P moved as a component of sediments. Cropping
decreased sediment and solution losses, while manure generally increased losses
in both. Most P moving in runoff solution was inorganic. However, except
where percolation swept inorganic P downward without reaction with the soil,
most P moving in leachate was organic. Fractionations of soil P revealed
that P treatments increased the HN4C1- and NH4F-extractable fractions markedly,
had less effect on the NaOH-extractable fraction, and had still less effect
on the H2SO4-extractable and organic fractions. All phosphorus sources
markedly increased the equilibrium P concentrations (EPC) of all soils. Manure
increased EPC more than the other sources in the Rossmoyne and Wauseon soils.
The tendency is for more sediment P to be lost from manure and for manure-
treated soil to mobilize P into solution, make erosion control especially im-
portant if much manure is to be applied to soils and if eutrophication of
surface waters is to be minimized.
78:053-004
SURVIVAL AND MOVEMENT OF FECAL INDICATOR BACTERIA IN SOIL UNDER CONDITIONS OF
SATURATED FLOW,
Hagedorn, C., Hansen, D.T., and Simonson, G.H.
Oregon State University, Corvallis, Department of Microbiology.
Journal of Environmental Quality, Vol. 7, No. 1, p 55-59, January-March, 1978.
2 fig, 3 tab, 8 ref.
Descriptors: *Bioindicators, *Septic tanks, *Soil disposal fields, *Water
pollution sources, *Sewage bacteria, Disposal, Soil contamination, Public health,
Coliforms, Bacteria.
Antibiotic-resistant fecal bacteria were used to monitor the degree of movement
and subsequent groundwater contamination by septic tank effluent discharged into
a drainfield under saturated conditions. Two pits of different depths were
constructed to simulate drainfield beds, and groundwater samples were removed
during thirty-two day sampling intervals from sampling wells installed at set
distances from each inoculation pit. The bacteria added to the deep pit were
released into a B2t horizon which contained a higher clay content than the A
horizon in which the shallower pit was installed. Streptomycin-resistant strains
of Escherichia coli and Streptococcus faecalis amended to each pit site moved in
a directional manner, required more time to reach sampling wells when inoculated
into the deeper of the two pits, and moved relatively long distances when con-
sidering that the area where the sites were located .had only a 2% slope.
Bacterial numbers peaked in the sampling wells in association with major rainfall
patterns and the populations required longer periods to peak in the wells
furthest from the inoculation pits. The results indicated that antibiotic-
resistant bacteria eliminated the problem of differentiating between the
amended bacteria and those nonresistant strains already in the soil, and the
potential is excellent for including this type of microbiological procedure
for assessing the suitability of a soil site for septic tank and waste water
drainfield installations.
78:05B-005
VIRUS ADSORPTION BY FIVE SOILS,
Surge, W.D., and Enkiri, N.K.
Agricultural Research Service, Beltsville, Maryland, Agricultural Environmental
Quality Institute.
Journal of Environmental Quality, Vol. 7, No. 1, p 73-76, 1978. 4 fig, 3 tab,
14 ref.
181
-------
Descriptors: *Bacteriophage, *Soil types, *Clay loam, *Silts, *Adsorption,
Waste water treatment, Sands, Loam, Sodium chloride, Cation exchange.
The Freundlich isotherm was applied to the adsorption kinetics of phi X-174
bacteriophage in five soil types with varying physical and chemical properties.
Adsorption rates of 6 ml of the bacteriophage were observed in 6 g samples of
Aastad clay loam, Kranzburg silt loam, Palouse silt loam, Parshall silt loam,
and Quincy loamy sand. The Freundlich isotherm and adsorption rate constants
were calculated for adsorption of the virus by the soil were also determined.
The Quincy soil with a pH of 7.2 showed no adsorption of the virus, due
possibly to its high organic content. Bacteriophage adsorption was represented
as a function of the square root of time. The cation exchange capacity, speci-
fic surface area, and organic carbon content of the soil correlated with the
virus adsorption rates of the four remaining soils. The influence of pH was
found to be significant in the adsorption of the virus by the soil.
78:05B-006
TRANSPORT OF ATRAZINE AND SIMAZINE IN RUNOFF FROM CONVENTIONAL AND NO-TILLAGE
CORN,
Triplett, G.B., Jr., Conner, B.J., and Edwards, W.M.
Ohio Agricultural Research and Development Center, Wooster.
Journal of Environmental Quality, Vol. 7, No. 1, p 77-84, January-March, 1978.
1 fig, 7 tab, 25 ref.
Descriptors: *Herbicides, *Runoff, *Weed control, *Farm management, Storm
runoff, Rainfall, Corn (field), Precipitation (atmospheric), Pollutants, Crops.
On 0.4- to 3.5-ha watersheds, highest concentrations of atrazine (0.48 ppm)
and simazine (1.2 ppm) were present in runoff occurring soon after application
and declined rapidly for later events. Quantity of herbicides transported
increased with the amount of runoff and was inversely related to the length of
time between application and the runoff event. A maximum of 6% of the applied
herbicide was transported from the field even under the most favorable condi-
tions, and the average for all watersheds was less than 2%. Less runoff and
herbicide loss occurred from areas planted to no-tillage than to conventional
corn. In a multiple regression analysis of the factors, the natural logarithm
(In) of days after application and a tillage X application rate interaction
were useful in predicting the natural logarithm of herbicide concentration in
runoff. Factors from the multiple regression analysis used in ttiis study were
important in predicting concentration of atrazine and other pesticides when
applied to data published by other workers.
78:058-007
PHOSPHATE ADSORPTION-DESORPTION CHARACTERISTICS OF SUSPENDED SEDIMENTS IN THE
MAUMEE RIVER BASIN OF OHIO,
Green, D.B., Logan, T.J., and Smeck, N.E.
Ohio Agricultural Research and Development Center, Wooster, Department of
Agronomy.
Journal of Environmental Quality, Vol. 7, No. 2, p 208-212, April-June, 1978.
3 fig, 3 tab, 15 ref.
Descriptors: *Phosphates, *Eutrophication, *Algae, Ohio, Water pollution,
*Phosphorus compounds, Water properties, Calcite, Surface runoff, Soil erosion.
Phosphorus (P) adsorption-desorption characteristics of Maumee River Basin
suspended sediments were compared with those of Basin soils and stream bottom
sediments. Suspended sediment contained more total P than either soils or
bottom sediments. The increase in total P over soils is attributed to enrich-
ment of P in sediment by selective erosion of fine particles and adsorption of
P during fluvial transport. The suspended sediment had higher adsorption maxima
than Basin soils, but lower than bottom sediments, and had lower adsorption
energies than either soils or bottom sediments. Calcite content of the sus-
pended sediments was correlated positively with total P, EPC (equilibrium P
concentration), and P desorbed and negatively correlated with adsorption
energy, implying that, although calcite is a sink for P, the adsorption is weak
compared with other sites for P adsorption such as hydrous oxides of Fe and Al.
182
-------
78:05B-008
SEASONAL RUNOFF LOSSES OF NITROGEN AND PHOSPHORUS FROM MISSOURI VALLEY LOESS
WATERSHEDS^,
Alberts, E.E., Schuman, G.E., and Burwell, R.E.
Journal of Environmental Quality, Vol. 7, No. 2, p 203-208, April-June 1978
6 tab, 21 ref. '
Descriptors: *Phosphates, *Nitrogen, ^Missouri, *Iowa, *Surface runoff, *Water
quality, *Soil erosion, *Nutrient removal, Phosphorus compounds, Sediments.
Seasonal losses of nitrogen and phosphorus in surface runoff were determined
for a seven-year period from three corn-cropped watersheds in southwestern
Iowa. Three seasonal periods were defined: fertilizer, seedbed, and esta-
blishment period from April through June (PI); reproduction and maturation
period from July through November (P2); and residue period from December through
March (P3). Most of the average annual total N and P losses were associated
with the sediment portion of runoff and occurred during PI. The extreme sus-
ceptibility of the loess soils to erosion during PI must be taken into account
when designing conservation practices to control plants nutrient losses.
Seasonal discharges of runoff, sediment, and nutrients were much lower from a
level-terraced watershed than from two contour-farmed watersheds, which demon-
strates the benefit of terracing in resource conservation. Average annual
soluble N and P losses were quite low and never exceeded 1% of the annual
fertilizer application. These losses were the highest during P3 from the
contour-farmed watersheds. Water and sediment weighted nutrient concentrations
were the highest from the contour-farmed watersheds during P3, when residues
covered the soil surface. Leaching of soluble nutrients from the residue
and the greater selectivity of the soil erosion process for the finer fractions
of the soil (i.e., clay and organic material) during snowmelt runoff are
probably the factors responsible.
78:058-009
A WATER QUALITY PLANNING MODEL WITH MULTIPLE TIME, POLLUTANT, AND SOURCE
CAPABILITIES,
DeLucia, R., McBean, E., and Harrington, J.
Meta Systems Inc., Cambridge, Massachusetts.
Water Resources Research, Vol. 14, No. 1, p 9-14, February, 1978. 4 fig, 12 ref.
Descriptors: *Water pollution control, *Planning, *Waste treatment, Constraints,
Optimization, Mathematical models, Systems analysis, Economies of scale.
The imposition of recent U.S. legislative requirements (Public Law (PL) 92-500)
with the 1977 and 1983-1985 water quality goals requires that water quality
management plans must weigh both degree of treatment and capacity expansion
questions. A planning model capable of reflecting the implications of the
pollutant constraints and the scale economies of point source abatement implicit
in the legislation is developed. The model captures within a mathematical pro-
gramming format important characteristics of decisions associated with the time-
related water pollution control goals of PL 92-500. The model's unique features
are the utilization of a biomass potential parameter as a measure of water quality
and a set of heuristic procedures involving linearization of the waste treat-
ment capacity-removal curves. These features allow avoidance of nonconvexity
problems associated with analogous models. The model also includes the usual
BOD, DO, N, and P water quality measures; it was applied in a recent planning
study for the Saint John Basin in Maine.
78:058-010
STEADY STATE RIVER QUALITY MODELING BY SEQUENTIAL EXTENDED KALMAN FILTERS,
Bowles, D.S., and Grenney, W.J.
Utah Water Research Laboratory, Logan.
Water Resources Research, Vol. 14, -No. 1, p 84-96, February, 1978. 11 fig, 3
tab, 14 ref, 1 append.
Descriptors: *Water quality, *Utah, *Rivers, *Model studies, *Mathematical
models., Pollutants, Dissolved oxygen, Water pollution, Biochemical oxygen demand.
Algae.
183
-------
Sequential extended Kalman filters (EKF) were applied as a technique for steady-
state river water quality modeling. The approach was demonstrated by using
water quality data collected over a 36.4-mi stretch of the Jordan River, Utah.
Each EKF was used to represent a river reach in which hydraulic and quality
characteristics were judged fairly uniform. Mean and variance boundary condi-
tions between successive filters were adjusted to represent the effects of
variance estimates of 'the system state (water quality parameters) ana confidence
intervals on these estimates were provided by combining two independent estimates
of the system state. The independent estimates were based on (1) predictions
from an "internally meaningful" model of the stream transport processes and bio-
chemical transformations, and (2) measurements of the water quality parameters.
The estimates were combined by a weighting procedure based on uncertainties
associated with each estimate. A smoothing algorithm also was applied in
order that estimates from passes of the filter procedure in both the downstream
and upstream directions could be combined. In this way, information contained
in the measurements was used both upstream and downstream of the location of the
measurement. The calibration capability of the filter procedure was demonstrated
by simultaneous estimation of the state vector and one of the model coefficients.
This capability also was used to estimate simultaneously the rate of lateral
loading for one of the water quality parameters. Simultaneous estimation of
coefficients of lateral loading was shown to increase the uncertainty associated
with filter estimates because of the inclusion of uncertainty associated with
these coefficients and lateral loading rates.
78:05B-011
EFFECT OF SOIL MIXTURES AND IRRIGATION METHODS ON LEACHING OF N IN GOLF GREENS,
Mitchell, W.H., Morehart, A.L., Cotnoir, L.J., Hesseltine, B.B., and Langton, D.N.,
III.
Delaware University, Newark, Department of Plant Science.
Agronomy Journal, Vol. 70, No. 1, p 29-35, January-February, 1978. 5 fig, 5 tab,
15 ref.
Descriptors: Leaching, Golf courses, Nitrogen, Nitrates, Mixing, Sprinkler
irrigation. Subsurface irrigation, Environmental effects, Turf grasses, Inhibitors.
The influence of soil mixtures, irrigation systems, and N sources on N leaching
was studied in experimental, though functional, golf greens from 1973 to 1976.
Sprinkler irrigation was compared with subsurface irrigation. Soil mixtures
contained from 60 to 80 percent sand and variable amounts of silt loam topsoil,
calcined clay and humus. Nitrogen treatments included activated sewage sludge,
ureaform, ammonium nitrate, 30% N solution, anhydrous ammonia and nitrapyrin.
Nitrogen leached primarily as NO3-N. Even though about 75% of the added was
NH4-N, N solution (30% N) applied through the subsurface irrigation system
caused a sharp increase in N03-N in the drainage water. Anhydrous ammonia with
or without nitrapyrin reduced NO3-N leaching losses for one to two weeks but
had little effect on the average N03-N concentration over a forty-seven day
period. Subsurface irrigation stimulated turfgrass growth in bands about 20 cm
wide located above the irrigation lines. Appearance of growth bands was
associated with low temperatures and increased levels of NO3-N in proximity to
the irrigation lines. Banding was most apparent in soil mixtures containing low
levels of residual soil N and absent when turfgrass was adequately fertilized
with N.
78:058-012
NATURAL VEGETATION AS A SOURCE OF DIFFUSE SALT WITHIN THE COLORADO RIVER BASIN,
Malekuti, A., and Gifford, G.F.
Utah State University, Logan,'Department of Range Science.
Water Resources Bulletin, Vol. 14, No. 1, p 195-205, February, 1978. 8 fig,
4 ref.
Descriptors: *Salts, *Colorado River Basin, *Ranges, ^Vegetation, Leachate,
Overland flow, Gullies, Channels, Dissolved solids, Subsurface flow.
Foliage and litter leachate from selected natural vegetation in the Price River
Basin (within the Upper Colorado River Basin) was studied to determine the
probable impact of plants on the amount of diffuse salt movement from rangeland
watersheds. Calculations using concentrations of various leachates and
184
-------
characteristics of range sites expected to be high salt producers indicated that
plants contribute between 0.01 and 0.02% or less of the total annual salt load
to the Price River. Therefore, it was concluded that plants are not a significant
source of diffuse salt within the Colorado River Basin.
78:058-013
LINE SOURCE DISPERSION WITH APPLICATION TO MIXING IN RIVER CHANNELS,
Shen, H.T.
Clarkson College of Technology, Potsdam, New York, Department of Civil and
Environmental Engineering.
Water Resources Bulletin, Vol. 14, No. 1, p 35-45, February, 1978. 4 fig, 22 ref.
Descriptors: *Dispersion, *Solutes, *Rivers, *Model studies, *Path of pollutants,
Channel flow, Lime, Mixing, Uniform flow, Hydraulics.
Two-dimensional solutions for transient dispersion of nonconservative dispersants
in uniform flow resulting from a transverse line source of variable concentration
were obtained using multiple integral transformations. In general, the solutions
were in integral forms, which can be evaluated efficiently using Filon's
quadratures. Examples were presented for cases of practical interest. Applicabi-
lity of the solution for modeling dispersion in natural river channel where the
distribution of flows across the channel is nonuniform was discussed.
78:058-014
ASSESSMENT OF METHODS FOR COMPUTING STORM RUNOFF LOADS,
Wu, J.S., and Ahlert, R.C.
Rutgers University, Piscataway, New Jersey, Department of Chemical and Biochemical
Engineering.
Water Resources Bulletin, Vol. 14, No. 2, p 429-439, April, 1978. 1 fig, 1 tab,
21 ref.
Descriptors: *Storm runoff, *Water pollution sources, *Model studies, Mathematical
models, Evaluation, Land use, Water quality, Path of pollutants, Runoff, Computer
models.
Nonpoint source pollution has been characterized, in magnitude and in concentrations
of pollutants, by intermittent and impulse-type discharges into receiving waters,
causing shockloading problems for the ecosystems of these water bodies. The
quality of storm runoff appears random and complex in nature. There are not yet
universally applicable assessment tools for analysis and evaluation of the impacts
and contributions of pollutant loads to receiving waters. This paper reviewed
and recommended methods for predicting storm runoff loads. The state-of-the-art
for storm runoff pollution prediction includes: zero-order, direct, statistical,
and descriptive methods. For transient water quality analysis of individual
storm events, it is essential to have an efficient sampling program for data
collection and a technically sounded method of data analysis. Intensive sampling
is considered necessary to a detailed time history of runoff flows and loadings
within a storm and for a limited number of storms. Homogeneous-land-use and
statistical-synthetic approaches are recommended as accurate and practical
methods for storm-runoff-load..prediction. These two approaches are event-oriented,
predicting time-varying runoff loads for transient water quality analysis, uti-
lizing data collected from intensive sampling programs.
78:058-015
MODEL FOR SHORT-ATTACHED THERMAL PLUMES IN RIVERS,
Paily, P.P., and Sayre, W.W.
NALCO Environmental Sciences, Northbrook, Illinois.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
104, No. HY5, Proceedings Paper 13762, p 709-723, May, 1978. 8 fig, 1 tab,
18 ref, 2 append.
Descriptors: *Thermal pollution, *Rivers, *Powerplants, *Missouri river, Model
studies, Mathematical models, Turbulence, Heated water, Temperature, Mixing.
Side discharges of power plants thermal effluents into natural rivers cause the
formation of thermal plumes, the shape and orientation of which depend upon both
185
-------
the discharge conditions and the ambient flow characteristics. When the
turbulence level of the ambient flow is high, rapid vertical mixing is achieved
between the effluent discharge and the river flow, and the thermal plume becomes
shore-attached with the maximum temperatures within the plume occurring along
the near shore. In order to determine the isotherm patterns within shore-
attached thermal plumes, a solution of the depth-integrated steady-state
convection-diffusion equation was obtained. The solution was cast in terms of
space-cumulative discharge coordinates, thus allowing the inclusion of the
effects of cross-channel flow induced by channel curvature in the model.
78:05B-016
TWO-DIMENSIONAL PLUME IN UNIFORM GROUNDWATER PLOW,
Wilson, J.L., and Miller, P.J.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers; Vol.
104, No. HY4, Proceedings Paper 13665, p 503-514, April, 1978. 6 fig, 17 ref,
3 append.
Descriptors: *Groundwater, *Dispersion, *Water pollution, *New York, Model
studies, Mathematical models, Adsorption, Path of pollutants, Wells, Groundwater
movement.
A simple analytical model of a two-dimensional plume of groundwater pollution
was developed and applied to the study of hexavalent chromium contamination of
Long Island, New York. The model was based on a depth-averaged mass transport
equation accounting for convection, dispersion, linear equilibrium adsorption,
and decay, and was applicable to the study of pollution migration from point
sources in shallow groundwater aquifers. The pollutant concentration description
was based on a depth-averaged mass transport equation accounting for convection,
dispersion, linear equilibrium adsorption, and decay, and was applicable to the
study of pollution migration from point sources in shallow groundwater aquifers.
The pollutant concentration description was based on an asymptotic solution to
Hantush's well function for a leaky aquifer and was accurate in the far field
downstream of the source. The model results were easily visualized and evaluated
when plotted as contour lines of equal concentration using a simple graphical
procedure, making it convenient to examine the development of the plume over
time and to evaluate the sensitivity of the plume to parameters.
78:058-017
DISPERSIVE SOURCES IN UNIFORM GROUNDWATER FLOW,
Hunt, B.
Canterbury University, Christchurch, New Zealand, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
104, No. HY1, Proceedings Paper 13467, p 75-85, January, 1978. 2 fig, 9 ref, 3
append.
Descriptors: *Dispersion, *Groundwater, *Uniform flow, *Water pollution sources,
Water resources, Steady flow, Groundwater movement, Model studies, Mathematical
mode'ls, Equations.
Solutions were given for instantaneous, continuous, and steady-state sources of
pollution in uniform groundwater flow. Then the solutions were used to determine
how long a continuous source must be in place before steady-state conditions are
approached, to determine the effect of a finite aquifer depth upon solutions for
an infinite aquifer depth, to calculate maximum concentrations for instantaneous
sources, and to determine the time required for solutions for a po'int source and
a source of finite size to approach each other.
78:05B-018
SIMULATION OF NITROGEN MOVEMENT, TRANSFORMATIONS, AND PLANT UPTAKE IN THE ROOT
ZONE,
Davidson, J.M., Rao, P.S.C., and Selim, H.M.
Florida University, Gainesville, Department of Soil Science.'
In: Proceedings of National Conference on Irrigation Return Flow Quality Manage-
ment, Colorado State University, Fort Collins, Colorado, p 9-18, May 16-18, 1977.
7 fig, 1 tab, 28 ref.
186
-------
Descriptors: *Simulation analysis, Model studies, Nitrogen, Soil water, Soil
water movement, Irrigation, Nitrification, Denitrification, Mineralization.
Two simulation models, a detailed research-type and a conceptual management-type,
for describing the fate of nitrogen in-the plant root zone are discussed. Pro-
cesses considered in both models were: one-dimensional transport of water and
water-soluble N-species as a result of irrigation/rainfall events, microbiologi-
cal N-transformations and uptake of water and nitrogen species by a growing crop.
The research-type model involves a finite-difference approximation (explicit-
implicit) of the partial differential equations describing one-dimensional water
flow and convective-dispersive NH4 and NO3 transport, along with simultaneous
plant uptake and microbiological N-transformations. Ion-exchange (adsorption-
desorption) of NH4 was also considered. The microbiological transformation
incorporated into the model describe nitrification, denitrification, minerali-
zation and immobilization. All transformation processes were assumed to be
first-order kinetic processes. The numerical solution was flexibile in its
soil surface boundary conditions, as well as initial conditions for soil water
content and nitrogen concentration distributions in the soil profile. The
solution can also be used for nonhomogeneous or multilayered soil systems. The
research-type model involves a detailed description of the individual process
and requires a large number of input parameters, most of which are frequently
unavailable. Because of this, a more simple management-type model was developed.
Several simplifying assumptions were introduced into the management model.
This model requires a minimal amount of input data by the user, and provides
a gross description of the behavior of various nitrogen species in the plant
root zone.
78:05B-019
TRANSPORT OF MICROORGANISMS IN SAND COLUMNS,
Wollum, A.G., II, and Cassel, O.K.
North Carolina State University, Raleigh, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 1, p 72-76, January-February,
1978. 6 fig, 5 tab, 8 ref.
Descriptors: Micoorganisms, Saturated flow, Wastes, Sewage effluents, Bacteria.
Transport of streptomycete conidia through saturated columns of uniformly packed
sand was studied using miscible displacement techniques. Autoclaved sand was
uniformly packed to give sand columns 20.3 and 152 cm high. Mean pore water
velocities ranged from 14.4 to 131 cm/hour. A pulse of sterile water containing
from 10000 to 1000000 conidia and tagged with 36C1 was displaced through each
column with sterile water. Column effluent was collected'and analyzed for
conidia by serial dilution techniques utilizing starch-casein agar. At the termi-
nation of each run, the column was sampled and analyzed for conidia distribution.
78:058-020
A CASE STUDY-NITRATES IN THE UPPER SANTA ANA RIVER BASIN IN RELATION TO GROUNDWATER
POLLUTION,
Ayers, R.S.
California University, Davis, Department of Land, Air and Water Resources.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agricul-
ture, California University, Sacramento, California, p 355-367, May 15-18, 1978.
2 fig, 1 tab, 4 ref.
Descriptors: Nitrates, Nitrogen, Water managment (applied), Fertilization, Waste
disposal, Pollutant identification.
In response to a request from the Santa Ana Watershed Planning Agency (a regional
planning agency) the Kearney Foundation of Soil Science of the University of
California conducted an interdisciplinary three-month study of the nitrate prob-
lem in the Basin. The study was limited to the upper part of the basin where
nitrate degradation of waters was more serious. The study included 1) a review
of available data to identify existing areas of high nitrate concentrations in
underground waters, 2) a review of past land use, water and fertilizer use and
waste disposal practices, and 3) estimates of the impact of irrigation, fertili-
zation and use of animal wastes on leaching of nitrate from root zones. Guide-
lines for the use of water, fertilizers and manures were developed.
187
-------
78:05B-021
ESTIMATING THE INFLUENCE OF SOIL RESIDENCE TIME ON EFFLUENT WATER QUALITY,
Jury, W.A.
California University, Riverside, Department of Soil and Environmental Sciences.
Proceedings of National Conference on Management of Nitrogen in Irrigated Agri-
culture, California University, Sacramento, California, p 265-290, May 15-18,
1978. 6 fig, 1 tab, 30 ref, 12 equ.
Descriptors: Effluents, Water quality, Travel time, Drainage, Tile drainage,
Nitrates.
Models are proposed to calculate the time required for dissolved chemicals to move
from the soil surface to either underlying groundwater in the case of free drain-
age or to tile drain outlets in the case of artificial drainage. The models
assume that dissolved substances are transported primarily by moving soil solu-
tion, which displaces soil water initially present in the wetted pore space
(piston flow approximation). For free drainage, this results in a single travel
time equation which is a function of soil water content and drainage volume. For
tile drainage, the travel time /depends also on the surface entry point, which is
illustrated with a graph showing residence time as a function of place or origin.
This graph may be used for all tile drain systems. Calculations are presented
to show the influence of travel time on drainage concentrations, illustrating
also how tile drain concentrations are a mixture of contributions from different
parts of the field arriving at different times. Field studies of salt movement
are analyzed and compared to the model predictions, with differences explained on
the basis of soil variability or stagnant water in part of the wetted pore space.
78:058-022
"BEST MANAGEMENT PRACTICES" FOR SALINITY CONTROL IN GRAND VALLEY,
Walker, W.R., Skogerboe, G.V., and Evans, R.G.
Colorado1 State University, Fort Collins, Colorado, Department of Agricultural
and Chemical Engineering.
Publication No. EPA-600/2-78-162, July, 1978. 113 p, 21 fig, 11 tab, 46 ref.
Descriptors: Irrigation, Fluid infiltration, Salinity, Seepage, Water distribution,
Water loss, Water pollution, Water quality, Sprinkler irrigation.
A nontechnical summary of several research activities in the Grand Valley is given.
Analyses of alternative measures of reducing the salt load originating from the
Valley as a result of irrigation return flows are presented. These alternatives
include conveyance channel linings, field relief drainage, on-farm improvements
(such as irrigation scheduling, head ditch linings, sprinkler and trickle irriga-
tion) , economic control measures such as taxation and land retirement, modified
legal constraints, and collection and treatment of return flows, with desalting
systems. The best management practices for salinity control in the Grand Valley
should be primarily the structural rehabilitation and operational modification
of the local irrigation system lying below the turnouts from the major canal
systems. Canal linings appear in the optimal strategies at higher levels of
valley-wide salinity control emphasis but only so far as lining the Government
Highline Canal is concerned. Desalting would become a cost-effective alternative
after major irrigation system improvements are implemented.
78:058-023
LOSS OF SPRAY AND PELLETED PICLORAM IN SURFACE RUNOFF WATER,
Bovey, R.W., Richardson, C., Burnett, E., Merkle, M.G., and Meyer, .R.E.
Agricultural Research Service, College Station:, Texas.
Journal of Environmental Quality, Vol. 7, No. 2, p 178-180, April-June, 1978.
3 tab, 9 ref.
Descriptors: *Texas, "Herbicides, *Agricultural runoff, *Weed control, *Pesticide
residues, ^Surface runoff, Watersheds (basins), Rainfall, Precipitation (atmo-
spheric), Rainfall-runoff relationships.
This investigation was. conducted to determine the concentration of picloram,
applied as the pelleted formulation, in surface runoff water that may move from
a treated watershed to untreated areas as a result of natural or simulated rainfall*
Movement of surface and subsurface applied picloram in surface runoff water also
188
-------
was investigated. The potassium salt of pelleted picloram was applied at 2.24
kg/ha (acid^equivalent) to a 1.3-ha rangeland watershed supporting stands of
honey mesquite. Surface runoff of 1.5 cm from a 2.1 cm rain received two days
after treatment contained an average of 2.8 ppm picloram. Picloram content
declined rapidly and runoff water contained less than 5 ppm picloram by 2.5 mo
after application. Loss of the potassium salt of picloram from grassland*
watersheds in surface runoff water was similar whether the picloram was applied
as an aqueous spray or as a pellet. Picloram applied subsurface was lost in
surface runoff water, but in lower concentrations than when applied to the soil
surface.
78:058-024
ARSENIC CONCENTRATIONS IN SURFACE RUNOFF FROM SMALL WATERSHEDS IN TEXAS,
Richardson, C.W., Price, J.D., and Burnett, E.
Agricultural Research Service, Temple, Texas.
Journal of Environmental Quality, Vol. 7, No. 2, p 189-192, April-June, 1978.
1 fig, 5 tab, 10 ref.
Descriptors: *Arsenicals (pesticides), *Cotton, *Texas, *Desiccants, Arsenic
compounds. Water quality, Pesticides, Surface runoff, Soil contamination.
This study was conducted to determine the movement of arsenic by surface runoff
after application of arsenic acid for desiccation of cotton. Arsenic acid was
applied at 6.6 kg/ha during the cotton year of a cotton-grain sorghum-oats
rotation. The concentration of arsenic dissolved in the runoff water was highest
during the first runoff event after application and decreased during subsequent
events. Arsenic concentrations in the first runoff after treatment ranged from
250 to 18 ppb, depending on time and tillage after application. Tillage that
incorporated treated plant material into the soil reduced arsenic concentration
in runoff water. After two or three runoff events, the arsenic concentration
decreased to 10 to 20 ppb and remained essentially constant until the next appli-
cation three years later. The arsenic concentration of the sediment from the
watersheds averaged 20 ppm and appeared to be related more to the arsenic con-
tent of the soil than to the length of time or the tillage between arsenic acid
application and first runoff. Assuming average annual runoff and sediment yield,
the amount of arsenic that would be transported from a watershed by runoff and
erosion is about 7% of the:amount applied. Part of the arsenic that moves from
a watershed may be arsenic that occurs naturally in the soil. Of the total
arsenic moved by a watershed, 38% would be in solution and 62% would be attached
to the sediment.
78:05B-025
DISPOSITION OF 15N-LABELED FERTILIZER NITRATE APPLIED DURING CORN CULTURE IN
FIELD LYSIMETERS,
Chichester, F.W., and Smith, S.J.
Grassland-Forage Research Center, Temple, Texas.
Journal of Environmental Quality, Vol. 7, No. 2, p 227-233, April-June, 1978.
3 fig, 5 tab, 21 ref.
Descriptors: Nitrates, Fertilizers, Water quality, Denitrification, Leachate,
Runoff, Nitrogen cycle, Lysimeters, Sweet corn, Ohio.
Calcium nitrate labeled with 5.5% 15N was applied at 336 kg/ha nitrogen (N) to
each of two conventional tillage and two mulch minimum tillage field lysimeters
continuously cropped to corn (Zea mays L.). Disposition of the labeled N was
followed for three years, particularly relative to its effect on water quality.
An accounting of applied 15N for the study period showed that< 2% moved in runoff,
approximately 30% was leached in percolate, 25 to 30% was recovered by the corn
crop, and from 10 to 30% remained in the soil. On the basis of a balance sheet
constructed from the data, 15N gaseous loss (presumably mainly by denitrification)
was estimated to range from 6 to 26% of that applied. The magnitude of gaseous
loss of N appeared to vary as a function of lysimeter management history, with
the systems under improved soil fertility management exhibiting less gaseous
loss due to greater immobilization of 15N in the soil organic fraction.
189
-------
78:058-026
PERSISTENCE OF TEBUTHIURON IN SURFACE RUNOFF WATER, SOIL, AND VEGETATION IN THE
TEXAS BLACKLANDS PRAIRIE,
Bovey, R.W., Burnett, E., Meyer, R.E. , Richardson, ~C., and Loh, A.
Agricultural Research Service, College Station, Texas.
Journal of Environmental Quality, Vol. 7, No. 2, p 233-236, April-June, 1978.
5 tab, 12 ref.
Descriptors: *Herbicides, *Agricultural chemicals, Water quality, *Texas, Urea
pesticides, *Agricultural runoff, Leaching, Soil contamination, Water pollution
sources, Persis tence.
The concentration of tebuthiuron herbicide applied in the spray or pellet form
was measured in surface runoff water from watersheds which received natural or
simulated rainfall. The persistence of tebuthiuron in soil and vegetation was
also investigated. Pelleted tebuthiuron was applied at 2.24 kg/ha (active
ingredient) to a 1.3-ha rangeland watershed. A 2.8-cm rain, two days after
application, produced 0.94 cm runoff which contained an average of 2.2 ppm of
tebuthiuron. Tebuthiuron concentration decreased rapidly with each subsequent
runoff event and after 3 mo was less than 0.05 ppm; none was detected in runoff
water one year after treatment. The concentration of tebuthiuron, applied as a
spray at 1.12 kg/ha, decreased to less than 0.01 ppm within 4 mo in runoff from a
small plot which received simulated rainfall. On 0.6-ha plots, mean tebuthiuron
(sprays and granules) concentration was 0.50 ppm or less in water when the first
runoff event occurred 2 mo after application. Concentrations of tebuthiuron in
soil and grass from pellet applications were Ibst (less than 1 ppm) and decreased
with time.
78:058-027
THE EFFECT OF HIGH 2,4-D CONCENTRATIONS ON DEGRADATION AND CARBON DIOXIDE
EVOLUTION IN SOILS,
Ou, L-rT. Rothwell, D.F. , Wheeler, W.B., and Davidson, J.M.
Florida University, Gainesville, Department of Soil Science and Food Science.
Journal of Environmental Quality, Vol. 7, No. 2, p 241-246, April-June, 1978.
6 fig, 6 tab, 13 ref.
Descriptors: Pesticides, Herbicides, Pesticide residues, Persistence, Microbial
degradation, Pesticide toxicity, Carbon dioxide, Waste disposal.
A laboratory experiment was conducted to determine the degradation of high
concentrations of 2,4-D (2,4-dichlorophenoxyacetic acid) and C02 evolution in
three soils. Two forms of 2,4-D technical grade and formulated, were added to each
soil at rates of 50, 500, 5,000 and 20,000 micrograms/g of soil (ppm). Degradation
of the 2,4-D was measured by 14C02 evolution resulting from the oxidation of uni-
formly ring-labeled carbon. At an application rate of 500 ppm, all three soils
degraded 2,4-D. At 5,000 and 20,000 ppm, degradation occurred in the Webster
silty clay loam and Terra Ceia organic soil, but not in the Cecil sandy loam
during 80 days of incubation. The degradation rate was generally higher for the
formulated 2,4-D than the technical grade material. For the higher 2,4-D concen-
trations, 5,000 or 20,000 ppm, when extensive degradation occurred, total C02
evolution was also greatly stimulated, and the pattern of total C02 evolution rate
exhibited a two-peak response. Carbon dioxide-carbon (C02-C) from the first peak
appeared to be mainly from the formulation materials or from the impurities and
C02-C from the second peak was mainly from 2,4-D-C.
78:058-028
PARAQUAT SORPTION AS A FUNCTION OF PARTICLE SIZE IN NATURAL SEDIMENTS,
Karickhoff, S.W., and Brown, D.S.
Environmental Research Laboratory, Athens, Georgia 30605.
Journal of Environmental Quality, Vol. 7, No. 2, p 246-252, April-June, 1978. 1
fig, 6 tab, 13 ref, 9 equ.
Descriptors: Paraquat, Sorption, Adsorption, Particle size, Pesticides, Pollutants/
Sediments, Isotherms, Cation exchange, Clay minerals.
The distribution of sorbed paraquat as a function of particle size (sand through
clay) was determined on five natural sediments. Paraquat concentrations in
190
-------
individual size fractions varied as much as two orders of magnitude within a
given sedimeht, showing a pronounced preference for the fine silt and clay
fractions. Adsorption isotherms were measured for individual size separates
on one sediment. Paraquat distributions in the whole sediment agreed well
with those computed using the isotherm coefficients determined on individual
size separates. Paraquat sorbs by ion exchange, and sorption partition co-
efficients showed a definite correlation with the cation exchange capacity
(CEC) of individual size fractions. However, exchange sites in different
fractions differed in their effectiveness in sorbing paraquat, with the fine
silt and clay exchange sites being more effective than those of the larger
separates. In pure clay suspensions (hectorite and montmorillonite), sorbed
paraquat did not distribute uniformly throughout the clay particle size
range. It was concluded that for highly sorbed compounds such as paraquat,
conventional phase separation techniques for measuring sorption may not
distinguish sorbed vs. "free" compounds.
78:058-029
FATE OF 2, 4-D IN A NAFF SILT LOAM SOIL,
Wilson, R.G., Jr., and Cheng, H.H.
Nebraska Panhandle Station University, Scottsbluff.
Journal of Environmental Quality, Vol. 7, No. 2, p 281-286, April-June, 1978.
3 fig, 4 tab, 16 ref.
Descriptors: Adsorption, Hydrolysis, Chemical degradation, Microbial degrada-
tion, Weed control, Pesticides, Runoff.
Laboratory studies were conducted to determine the adsorption, desorption,
hydrolysis, and breakdown of commercially formulated isooctyl ester and di-
methylamine salt of (2,4-dichlorophenoxy) acetic acid (2,4-D) in a Naff silt
loam soil. More 2,4-D was adsorbed to the surface soil than to soil at lower
depths, and the percentage of 2,4-D adsorbed decreased as the total amount of
2,4-D present increased. Formulated 2,4-D isooctyl ester applied to moist
soil underwent hydrolysis to the anionic form at a rapid rate, with >80% of the
ester hydrolyzed in 72 hours. High amounts of 2,4-D in runoff (sediment and
water) retarded the active degradation of carboxyl-14C 2,4-D when 2,4-D was
incubated in runoff from a wheat field treated with various formulations and
rates of 2,4-D. The presence of the ester formulation at the high rate of
application increased the lag period before degradation of carboxyl-14C and
ring-14C 2,4-D occurred in soil. However, once the active breakdown of
carboxyl-14C and ring-14c 2,4-D was initiated, little difference could be
detected in the degradation patterns. At the end of the 10 weeks of incubation
in runoff or in soil, only 1% of the 14C-2, 4-D originally applied to the soil
could be identified as 2,4-D.
78:058-030
TRANSFORMATION AND TRANSPORT PROCESSES IN AQUATIC SYSTEMS,
Baughman, G.L.
Environmental Research Laboratory, United States Environmental Protection
Agency, College Station Road, Athens, Georgia 30601.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
p 98-102. 25 ref, 1 equ.
Descriptors: Pesticide kinetics, Pesticide removal, Pesticides, Aquatic
environment, Chemical degradation, Pollutants, Water pollution, Water pollution
control, Water quality, Volatility.
Dynamics of transformation and transport are described in terms of their controlling
environmental parameters. Recent advances in our ability to mathematically
describe the rate and extent of microbiological, chemical, and physical processes
are discussed and data are presented to illustrate interrelationships between
these processes.
191
-------
78:058-031
ESTIMATION OF ORGANOCHLORINE PESTICIDE LOSS IN SURFACE RUNOFF WATERS,
Bobovnikova, Ts.I., Virchenko, E.P., Morozova, G.K., Sinitsyna, Z.A., and
Cherkhanov, Yu.P.
Institute of Experimental Meteorology, Obninsk, Union of Soviet Socialist
Republics.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
p 103-107. 1 ref, 1 egu.
Descriptors: Pesticide removal, Pesticides, Pollutants, Runoff, Water quality,
Water pollution sources. Water pollution, Estimating.
Pesticide migration in water is one of the major pathways of their transport in
the environment. Surface runoff water which occurs at the watershed as the
result of snowmelt or rainfall causes pesticide removal from the watershed area
(agricultural lands and forests) and their entering rivers and basins. Investi-
gations in Russia showed that surface runoff from the watershed was the major
source of river water pollution with pesticides. The experimental results
obtained show that the loss coefficients of organochlorine.pesticides—DDT and
gamma-BBC—were low both at the natural watersheds and at the experimental runoff
plots -{tenth and hundredth fractions of percent). The gamma-BHC loss coefficient
did not exceed 3.7% even when gamma-BHC was applied in the snow cover before the
snowmelt, that is under the best runoff conditions.
78:058-032
HEXACHLOROCYCLOHEXANE,' METAPHOS, AND CHLOROPHOS DECOMPOSITION IN SOIL AND THEIR
MIGRATION WITH THE WATERS OF SURFACE RUNOFF,
Tarasov, M.N., Korotova, L.G., Demchenko, A.S., and Bra2hnikova, L.V.
Hydrochemical Institute, Novocherkassk, Union of Soviet Socialist of Republics.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
p 108-116. 3 fig, 2 tab, 1 equ.
Descriptors: Pesticides, Pesticide removal, Pesticide kinetics, Runoff, Pollutants,
Pollution abatement, Water quality, Water pollution.
Great quantities of chemicals and among them pesticides> enter the biosphere due
to intensive chemicalization of agriculture. «Upon the influence of different
factors the greater part of pesticides is decomposed in soil forming primary
products and certain preparations are preserved in soil for a long time due to
high persistency. Systematic usage of persistent pesticides and those with high
cumulative properties at vast watersheds occupied by agricultural lands may result
in pollution of natural waters. In order to predict pollution of natural bodies
by pesticides, it is necessary to study the rate of their decomposition in
different soils, migration capability as well as to obtain quantitative charac-
teristics of their removal from agricultural lands. This paper reports the re-
sults obtained from studies of hexachlorocyclohexane (BHC), metaphors, and
chlorophors decomposition in soil, their migration capability as well as the
possibility of washing out by surface runoff.
78:053-033
CERTAIN LAWS OF ORGANOCHLORINE PESTICIDE REDISTRIBUTION IN THE SOIL-WATER,
SOIL-PLANT SYSTEM,
Zhdamirov, G.G., Popov, E.E., and Lapina, N.F.
Institute of Experimental Meteorology, Obninsk, Union of Soviet Socialist
Republics.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens,
Georgia, p 47-60. 4 fig, 3 tab, 9 ref.
Descriptors: Pesticides, Pesticide residues, Evaporation, Sorption, DDT,
Environmental effects. Estimating, Persistence, Barley, Clovers.
One of the objectives of this research work was to find the simplest method of
estimating organochlorine pesticide evaporation from soils, water, and surfaces.
The other one was to determine the quantitative characteristics of pesticide
transport into various species of plants and their distribution in aerial and
root parts of plants depending on their content in soil.
192
-------
73:05B-034
GENERAL LAWS OF THE MIGRATION OF PESTICIDE RESIDUES IN THE DELTA LANDSCAPE UNDER
IRRIGATION, ,.
Sokolov, M.S.
Institute of Agrochemistry and Soil Science, Puschino, Union of Soviet Socialist
Republics, Academy of Sciences.
In: Symposium on Environmental Transport and Transformation of Pesticides
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
p 38-46.
Descriptors: Pesticide residues, Pesticides, Pollutants, Herbicides, Surface
runoff, Subsurface runoff, Self-purification, Migration, Water pollution,
Sorption.
The process of migration determines diverse after effects caused by biocides and
other zenobiotics (landscape-regional, regional-basin and global ones) in the
biosphere. Migration can be characterized as a complex of processes of redistri-
bution of zenobiotics (and the products of their transformation) in space and in
time. In the process of redistribution a pesticide can be transformed into
various products. The leftovers of the parent compound together with the pro-
ducts of its transformation are defined as pesticide residues. Xenobiotics are
mainly transported in aquatic medium, in atmosphere and through organism migration.
In the aquatic medium xenobiotics are transported in the form of a liquid runoff
(true solutions of electrolytes, compounds with neutral molecules, and colloidal
solutions), and in the form of a .solid runoff (suspensions, sorbed substances
with precolloidal particles or organo-mineral colloids). The subsurface transport
of xenobiotics is carried out principally in the form of a liquid runoff. This
paper reviews and analyzes investigations conducted on the aspect of migration
and transport of pesticide residues through surface and subsurface runoff.
78:058-035
BROMACIL IN LAKELAND SOIL GROUNDWATER,
Hebb, E.A., and Wheeler, W.B.
United States Department of Agriculture, Forest Service, Southeast Forest
Experiment Station, Marianna, Florida 32446.
Journal of Environmental Quality, Vol. 7, No. 4, p 598-601, October-December,
1978. 1 fig, 1 tab, 21 ref.
Descriptors: Pesticides, Herbicides, Leaching, Groundwater, Water pollution,
Water table, Pesticide residues, Persistence.
The objective of this study was to evaluate the probable magnitude of the problem
of the leaching of pesticides into groundwater under extreme conditions: a
sandy soil low in organic matter, a persistent and mobile herbicide applied at
a high rate, plentiful rainfall, and a water table within 6 m. Bromacil
(5-bromo-3-sec-butyl-6-methyluracil) was applied at the rate of 22 kg/ha to a
Lakeland sand bearing scrub vegetation of small oaks and poor grasses.
Groundwater (at depths ranging from 4.5 to 6 m) was sampled from bromacil
residue at weekly intervals for two years. Residue was first found in the
groundwater 3 mo after application and was highest (1.25 ppm) one month later.
Thereafter, the amount declined to <0.1 ppm in about a year and <0.001 ppm in two
years. Peaks in residues generally followed periods of increased rainfall by
about two weeks. Residues (0.24 ppm) were still detected in the surface soil
two years after application.
78:05B-036
CLOSED FORM SOLUTION FOR PESTICIDE LOSS IN RUNOFF WATER,
Steenhuis, T.S., and Walter, M.F.
Cornell University, Ithaca, New York, Department of Agricultural Engineering.
Paper No. 78-2031, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 27 p. 4 fig, 5 tab,
17 ref, 25 equ, 1 append.
Descriptors: Pesticide removal, Pesticide residues, Runoff, Erosion, Overland
flow, Adsorption, Pesticides, Regression analysis.
193
-------
A closed form solution for pesticide loss in overland flow is presented based on
the principle that in a zone near the soil surface, mixing zone, rain, soil, and
pesticides intermix. All input variables are easily measurable except the depth
of the mixing zone. A depth of 0.9 cm for this zone was found by regression
using pesticide runoff data reported in literature. For verification, pesticide
runoff data from Southern Georgia was used and a reasonable agreement existed
between observed and predicted values.
78:05B-037
NONPOINT SOURCE POLLUTION FROM COASTAL PLAIN SOILS IN DELAWARE,
Ritter, W.F., Eastburn, R.P., and Jones, J.P.
Delaware University, Newark, Department of Agricultural Engineering.
Paper No. 78-2046, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 26 p. 6 fig, 11 tab,
14 ref.
Descriptors: Nutrient removal, Runoff, Surface runoff, Return flow, Pollutants,
Water pollution, Water quality, Agricultural watersheds, Rainfall, Delaware.
Nitrogen, phosphorus and organic matter were monitored on four agricultural
watersheds in the Delaware Coastal Plain. Total nitrogen and total phosphorus
loads in runoff and baseflow were less than the nitrogen and phosphorus loads
in rainfall.
78:053-038
SALT PICKUP BY OVERLAND FLOW IN THE PRICE RIVER BASIN, UTAH,
Ponce, S.L., and Hawkins, R.H.
Colorado State University, Fort Collins, Department of Earth Resources.
Water Resources Bulletin, Vol. 14, No. 5, p 1187-1200, October, 1978. 5 fig,
2 tab, 10 ref, 1 equ.
Descriptors: Salts, Saline soils, Salt balance, Overland flow, Shales,
Salinity, Utah, Water pollution, Water quality, Colorado River Basin.
This study emphasized a field investigation of salt release to overland flow
from Mancos shale lands of the Price River Basin, Utah. Although a high degree
of natural variation existed in the data, which precluded the separation of
factors affecting diffuse salt loading that occurs during overland flow, a
simplistic nonpoint source loading function developed on empirical concepts was
fit to the data. This function was then used to calculate the average annual
salt yield to the Price River by overland flow. It was found that even under
severe conditions, the salt yields from Mancos shale lands due to overland flow
is relatively minor, accounting for less than 1.5% of the average annual salt
mass transported from the basin by the Price River.
78:05B-039
CONTAMINANT TRANSPORT TO DEEP WELLS,
Weston, R.F., Phillips, K.J., and Gelhar, L.W.
Weston Incorporated, Rosyln, New York.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
104, No. HY6, Proceedings Paper 13824, p 807-819, June, 1978. 9 fig, 2 tab,
12 ref.
Descriptors: *Pollutants, *Water wells, *Groundwater, *Water pollution,
*Groundwater movement, *Groundwater quality, Wastes, Wells, Base flow, Model
studies, Soil water movement, Analytical techniques, Mathematical models,
Theoretical analysis, Water quality, Nitrates, Soil contamination, Well
contamination.
Described herein by analytical and numerical techniques was the process of
convective transport of a conservative contaminant to a deep, partially
screened pumping well overlain by a zone of contaminated water. The three-.
dimensional flow to the well was treated as a point sink in an anisotropic
medium. The effects of a regional downward flow, a phreatic surface above the
well, and an impervious lower boundary were evaluated. The theoretical results
were compared with the observed mitrate contamination of wells in Long Island,
194
-------
New York. It was shown that the local convective transport produced due to
pumping greatly accelerates the process of contamination and decontamination
of the wells.
78:05B-040
QUALITY OF PERCOLATE BELOW THE ROOT ZONE OF SELECTED VEGETABLES GROWN IN
NORTHERN GUAM,
Demeterio, J.L.
Guam University, Agana. Water Resources Research Center.
Completion Report PB-280 666, April, 1978, 28 p. 14 tab, 15 ref.
Descriptors: *Percolating water, *Water pollution, *Clays, *Fertilizers, *Guam,
Pesticides, Vegetables, Root zone, Sevin, Diazinon, Malathion, Dibron, Farm
wastes, Ammonium sulfate, Nitrogen, Phosphorus, Percolation, Potassium nitrate
Tomatoes, Cabbage, Peppers, Eggplant, Water quality.
Northern Guam farms were surveyed in 1976 and 1977 for pesticide and fertilizer
usage. The major pesticides used in 1976 and 1977 were sevin, diazinon, malathion,
and dibron. Kethane was widely used in 1976 but not in 1977. Animal manure,
15-15-15 and 16-16-16 were the most widely used fertilizers in 1976 and 1977.
A notable increase in the use of ammonium sulfate occurred in 1977. The chance
of groundwater contamination from agricultural chemicals is minimal since a very
small percentage of the land area is currently being utilized for full-time
farming. Bench scale lysimeter studies were conducted to determine the concen-
trations of nitrogen and phosphorus in percolate water after passing the root
zone of selected fertilized vegetables. Tomatoes, Chinese cabbage, head cabbage,
eggplant, and bell pepper were grown using ammonium sulfate, chicken manure,
potassium nitrate, and 15-15-15 as fertilizers. Potassium nitrate is the best
nitrogen source but is cost prohibitive and 15-15-15 percolates excessive amounts
of nitrate and ammonia nitrogen. Actively growing vegetables used the nitrogen
in the ammonium sulfate and chicken manure at comparable rates.
78:053-041
ATMOSPHERIC NITROGEN AND PHOSPHORUS LOADING TO HARP LAKE, ONTARIO, CANADA,
Nicholls, K.H., and Cox, C.M.
Ontario Ministry of the Environment, Rexdale, Water Resources Branch.
Water Resources Research, Vol. 14, No. 4, p 589-592, August, 1978. 2 fig, 3 tab,
13 ref.
Descriptors: *Nitrogen, *Phosphorus, *Lakes, *Canada, *Harp Lake, Nutrients,
On-site investigations, On-site data collections, Atmosphere, Water pollution
sources. Precipitation (atmospheric), Rain, Snow, Trees, Pollen, Hydrogen
ion concentration, Water pollution.
Nitrogen and phosphorus in precipitation and dry fallout (aeolian sources), as
well as the pH of rainfall, were measured over Harp Lake in Ontario during 1974.
Weighted mean concentrations of total N and total P during the ice-free period
of collection were 1.91 mg N/l and 0.105 mg P/l. Winter concentrations of total
N were similar, but total P concentrations were much lower, averaging 0.013 mg/1
in fresh snow. Total atmospheric loading of P to the lake was 74.4 P/sq m yr,
and the total N loading was 1600 mg N/sq m yr. About 52%, or 39.0 mg P/sq m yr
of the total P loading from the atmosphere was total dissolved P (0,22-micrometer
filtrate), and 28%, or 20.6 mg P/sq m yr, of the total P loading was dissolved
reactive P ("orthophosphate" P). Dissolved inorganic N loading at 1010 mg N/sq
m yr comprised about 63% of the total N loading from the atmosphere. Pollen,
from a variety of trees surrounding the lake, contributed about 20% of the total
P input. The pH of rainfall samples ranged from 3.2-to 5.1 with a median value
of 3.9 (n = 14).
78:058-042
EFFECT OF PH ON THE ADSORPTION OF TRACE RADIOACTIVE CESIUM BY SEDIMENTS,
Elprince, A.M.
King Faisal University, Dammam, Saudi Arabia, Department of Soil and Water.
Water Resources Research, Vol. 14, No. 4, p 696-698, August, 1978. 1 fig, 1 tab,
12 ref.
195
-------
Descriptors: *Hydrogen ion concentration, *Cesium, *Adsorption, *Sediraents,
Trace elements, Radioactive wastes, Radioactivity, Model studies, Mathematical
models, Sampling, Surveys, Laboratory tests. Water pollution, Streams, Rivers.
The adsorption of trace radioactive cesium by sediments from the Savannah River
Plant area follows a theoretically expected linear relationship between In Kd
and the pH of the equilibrium solution, where Kd is the equilibrium distribution
coefficient: Cs adsorbed (meq/g)/Cs(+) in solution (meq/ml). Theoretically,
the slope of these plots is proportional to the fraction of surface area occupied
by pH dependent charges. Experimentally, the slope becomes 0 after removal of
hydroxy Al interlayers with citrate pretreatment. Thus, hydroxy Al interlayers
are the main source for the pH dependent charges making Cs+ adsorption pH
dependent.
78:058-043
NITROGEN INPUTS AND LOSSES TOBACCO, BEAN, AND POTATO FIELDS IN A _SANDY LOAM
WATERSHED,
Cameron, D.R., DeJong, R., and Chang, C.
Agriculture Canada, Swift Current, Saskatchewan.
Journal of Environmental Quality, Vol. 7, No. 4, p 545-55.0, October-December, 1978.
4 fig, 1 tab, 20 ref.
Descriptors: Nitrogen removal, Leaching, Nitrates, Denitrification, Fertilization*
Tobacco, Beans, Potatoes.
Results from a 2-year study concerned with additions and losses of N from cropped
fields in an intensively farmed sandy loam watershed in southern Ontario indicated
that heavily fertilized burley tobacco (220 kg N/ha per year) and potato (165 kg
N/ha per year) fields can potentially lose up to 52 and 92 kg N/ha per year,
respectively, from the 75-cm profile by leaching and denitrification. Mineral N
production rates calculated from results obtained in the field over the growing
season varied from 0.0 to 0.73 kg N/ha per year. The lower rate resulted from
leaching losses. The monitored N03-N profile distributions under fertilized bur-
ley tobacco and potato crops showed definite leaching patterns. Soil water samples
taken periodically from the potato field at 90 and 150 cm showed NO3-N moving
through the lower profile in response to rainfall 'events. A plot treated with
Cl showed no significant Cl leaching losses until early fall when rains moved
about 45% of the added Cl below 75 cm.
78:058-044
NUTRIENT RUNOFF FROM FERTILIZED AND UNFERTILIZED FIELDS IN WESTERN CANADA,
Nicholaichuk, W., and Read, D.W.L.
Research Station, Research Branch, Agricultural Canada, Swift Canada, Saskatchewan
S9H 3X2.
Journal of Environmental Quality, Vol. 7, No. 4, p 542-544, October-December, 1978.
2 tab, 13 ref.
Descriptors: Water quality, Nitrogen, Phosphorus, Sediments, Surface runoff,
Fertilization, Wheat, Snowmelt, Fallowing, Canada.
Nutrient transport in surface runoff from snow was measured from -fertilized and
unfertilized cropped and summer fallowed Wood Mountain loam fields in semiarid
southwest Saskatchewan. The amount of nitrogen lost from unfertilized fields
during spring runoff exceeded the limits purported to result in algal growth;
however, the loss was agronomically insignificant. It was concluded that since
the N and P concentrations in runoff from unfertilized fertile agricultural soils
exceed Saskatchewan Water Quality criteria, these guidelines may be regarded as
unattainable under the present system of cereal cropping in western Canada.
78:058-045
TEMPERATURE AND pH AS LIMITING FACTORS IN LOSS OF NITRATE FROM SATURATED ATLANTIC
COASTAL PLAIN SOILS,
Gilliam, J.W., and Gambrell, R.p.
North Carolina State University, Raleigh, Department of Soil Science.
Journal of Environmental Quality, Vol. 7, No. 4, p 526-532, October-December,
1978. 5 fig, 2 tab, 35 ref.
(See 78:02K-048)
196
-------
7S-.05B-046
NITROGEN AND PHOSPHORUS LOSSES FROM ORGANIC SOILS,
Duxbury, J.M., and Peverly, J.H.
Cornell University, Ithaca, New York, Department of Soil Organic Chemistry.
Journal of Environmental Quality, Vol. 7, No. 4, p 566-570, October-December,
1978. 3 fig, 2 tab, 15 ref.
Descriptors: Nutrient removal, Organic soils, Leaching, Nitrogen, Phosphorus,
Runoff, Drainage water, Water quality. Fertilization, Water pollution.
The nutrient content of drainage water from Histosols located in New York was
monitored from June 1975 through July 1977. Continuous flow records and
nutrient concentration data obtained from daily composite samples were used
to calculate annual nutrient outputs which ranged from 0.6 to 30.7 kg/ha for
P04(3-)-P, 39.2 to 87.5 kg/ha for NO3(-)-N, and <1.0 to 1.9 kg/ha for NH4(+)
-N. Nutrient concentrations in the drainage water increased with increasing
flow, so that the greatest output of nutrients was during late winter and
spring high-flow events. Maximum observed concentrations were 35 mg/liter
for NO3(-) and 10 mg/liter for PO4{3-)-P. The amount of N lost in drainage
water was similar at all sites and was about 10% of that mineralized; the
remainder was presumed to be denitrified. The fiftyfold variability in
phosphorus output appeared to be related to interactions within the soil pro-
file rather than fertilizer practices, although these probably contributed to
the generally high levels found. It was concluded that fertilizer nitrogen
additions were unlikely to affect the quantity of N03(-> leached. The study
showed that organic soils can contribute to N and P in land runoff in much
greater proportions than indicated by their area.
78:05B-047
REDOX POTENTIALS IN A CROPPED POTATO PROCESSING WASTE WATER DISPOSAL FIELD
WITH A DEEP WATER TABLE,
Smith, J.H., Gilbert, R.G., and Miller, J.B.
Snake River Conservation Research Center, Kimberly, Idaho 83341.
Journal of Environmental Quality, Vol. "7, No. 4, p 571-574, October-December,
1978. 2 fig, 2 tab, 9 ref.
Descriptors: Oxidation-reduction potential, Waste water (pollution), Waste
water disposal, Denitrification, Nitrification, Nitrogen, Nitrates, Flood
irrigation, Water pollution, Groundwater.
Kedox potential measurements were made in a field irrigated with potato processing
waste water at seven depths of 5 to 150 cm for 14 months. Irrigation with canal
water mixed with waste water in the summer, and with waste water in the winter,
decreased redox potentials in the field at some depths for a short time but not
enough to cause denitrification. However, as the soil temperature increased in
the spring, and decomposition of the accumulated waste organic matter accelerated,
redox potentials decreased after each irrigation at all observed depths. During
April, redox potentials low enough to promote denitrification (below +225 mV) at
90-, 120-, and 150-cm depths in the soil persisted for 2 weeks. Irrigation with
nondiluted waste water in June and July decreased .redox potentials and denitrifi-
cation occurred for up to 3 days after irrigations. As the soil temperature in-
creased in the spring, nitrification of accumulated organic matter increased soil
nitrates. Waste watlr irrigations from April to July promoted denitrification,
removing most of the nitrate from the soil, and thereby decreasing the potential
for groundwater pollution.
SIMAZINE4RESIDUE LEVELS IN IRRIGATION WATER AFTER DITCHBANK APPLICATION FOR WEED
CONTROL,
^teeeY^r^e6^^
JSSS 5-S&S2
1978. 8 fig, 2 tab, 20 ref.
197
-------
Descriptors: Aquatic weed control, Aquatic weeds, Herbicides, Irrigation water,
Water quality, Gas chromatography.
A field study was conducted to determine the amount of simazine <2-chloro-4,6-
bis (ethylamino)-s-triazine) likely to be found in irrigation water after ditch-
bank treatment for weed control. Resulting data are useful in evaluating the
potential impact of simazine on crops irrigated from sprayed canals. Canals -
were selected in California, Colorado, and Washington for the application of
simazine to both watered and dewatered sites at rates of 2.25 to 7.43 kg/ha.
Simazine levels in flowing canal water immediately after herbicide application
did not exceed 60 raicrograms/liter. In first-flow samples collected in the
spring from the sites that were dewatered at application, simazine levels peaked
at about 250 micrograms/liter within the treated section but decreased rapidly
to <5 micrograms/liter.
78-.05B-049
STREAM CHEMISTRY AND WATERSHED NUTRIENT ECONOMY FOLLOWING WILDFIRE AND
FERTILIZATION IN EASTERN WASHINGTON,
Tiedemann, A.R., Helvey, J.D., and Anderson, T.D.
United States Department of Agriculture Forest Service, Pacific Northwest
Forest and Range Experiment Station, Forest Hydrology Laboratory, Wenatchee,
Washington 98801.
Descriptors: Streams, Forest fires, Fertilization, Ureas, Ammonium compounds,
Nutrients, Water quality, Nutrient removal, Washington.
During the first three years after a severe wildfire in 1970, maximum
concentrations of nitrate-N (NO3-N) in stream water increased from prefire
levels of <0.016 to 0.56 mg/liter on a burned, unfertilized watershed and to
0.54 and 1,47 mg/liter on two watersheds that were burned and fertilized.
Maximum N03-N concentration in stream from an unburned watershed was 0.066 mg/
liter. Organic N concentrations in streamflow were nearly doubled during the
second year after fire compared to prefire levels. Concentrations of total
phosphorus in streams from one burned and two burned-fertilized watersheds were
1.5 to 3 times greater than from an unburned watershed. Combined concentrations
of Ca, Mg, K, and Na in streams prior to fire ranged from 12.0 to 14.9 mg/liter.
Concentrations declined to 7.4-10.5 mg/liter in streams from burned and burned-
fertilized watersheds during the second year after fire (1972) because of
dilution resulting from increased discharge and were still less in 1975 than pre-
fire levels. Average inputs of N, P, and the four cations during the five
years of study were 1.23, 0, and 3.56 kg/ha per year. Yearly N input from pre-
cipitation was sufficient to balance solution losses in three of the five post-
fire years. Cation losses in solution greatly exceeded precipitation inputs in
all years. Results indicate that fire and fertilization exerted negligible effects
on chemical water quality for municipal use.
78:058-050
EFFECT OF ENVIRONMENTAL FACTORS ON SURVIVAL OF SALMONELLA TYPHIMURIUM IN SOIL,
Zibilske, L.M., and Weaver, R.W.
Missouri University, Columbia, Department of Agronomy.
Journal of Environmental Quality, Vol. 7, No. 4, p 593-597, October-December, 1978.
6 tab, 18 ref.
Descriptors: Waste disposal, Pathogenic bacteria, Microorganism, Environment,
Laboratory tests, Persistence.
This investigation was undertaken in the laboratory to determine how accurately
salmonella survival can be predicted when environmental conditions are known.
Salmonella typhimurium was inoculated into two Texas soils, a clay^and a fine
sandy loam, using cattle manure slurry and saline as inoculum carriers. Soil
samples were incubated in the laboratory at three temperatures and moistures:
5, 22, and 39 C; and 0, 0.5, and >22 atm tension, respectively. Survival was
monitored for 12 weeks by direct spread plating of soil dilutions onto dulcitol-
iron thiosulfate (DIT) medium developed for this experiment; The DIT medium
restricted growth of normal soil microflora but allowed growth and differentiation
of S. typhimurium. Statistical evaluation of treatment effects was complex be-
cause of three factor interactions. Soil moisture and temperature.interacted as
198
-------
did soil moisture and inoculation method. Time as a factor strongly interacted
with moisture, soil, and temperature. S. typhimurium died within 1 week in dry
soil incubated at 39 C, interactions occurred that resulted in survival to 42
days. Survival at 5 and 22 C was comparable and-usually longer than at 39 C.
Salmonella populations increased in some samples at 3 days but declined
afterward.
78:053-052
TRANSPORT OP ANTIBIOTIC-RESISTANT ESCHERICHIA COLI THROUGH WESTERN OREGON
HILLSLOPE SOILS UNDER CONDITIONS OF SATURATED FLOW,
Rahe, T.M., Hagedorn, C., McCoy, E.L., and Kling, G.F.
Oregon State University, Corvallis, Department of Soil Science and Microbiology.
Journal of Environmental Quality, Vol. 7, No. 4, p 487-494, October-December
1978. 3 fig, 3 tab, 16 ref.
Descriptors: Sewage effluents, Coliforms, Groundwater, Water pollution, Tracers,
Waste disposal, Septic tanks, Sewage disposal, Perched water, Subsurface flow.
Field experiments using strains of antibiotic resistant Escherichia coli were
conducted to evaluate the events which would occur when a septic-tank drainfield
became submerged in a perched water table and fecal bacteria were subsequently
released into the groundwater. Three separately distinguishable bacterial strains
were inoculated into three horizontal lines installed in the A, B, and C horizons
of two western Oregon hillslope soils. Movement was evaluated by collecting
groundwater samples from rows of modified piezometers (six piezometers/row)
placed at various depths and distances downslope from the injection lines. Trans-
port of E. coli differed at both sites with respect to movement rates, zones in
the soil profiles through which major translocation occurred, and the relative
numbers of cells transported over time. Movement rates of at least 1,500 cm/hour
were observed in the B horizon at dhe site. The strains of E. coli survived in
large numbers in the soils examined for at least 96 hours and appeared to be
satisfactory as tracers of subsurface water flow. The concept of partial dis-
placement (or turbulent flow through macropores) was discussed as an explanation
of the rapid movement of substantial numbers of microbial cells through saturated
profiles.
78:05B-053
LEACHING OF CATIONS AND CHLORIDE FROM MANURE APPLIED TO AN IRRIGATED SOIL,
Pratt, P.F.
California University, Riverside, Department of Soil Science.
Journal of Environmental Quality, Vol. 7, No. 4, p 513-516, October-December,
1978. 3 fig, 15 ref, 8 equ.
(See 78:05G-042)
78:058-054
EFFECTS OF SO2 AND NO2 ON NITRIFICATION IN SOIL,
Labeda, D.P., and Alexander, M.
Abbott Laboratories, North Chicago, Illinois 60064.
Journal of Environmental Quality, Vol. 7, No. 4, p 523-526, October-December, 1978.
4 fig, 1 tab, 24 ref.
Descriptors: Air pollution, Nitrification, Nitrates, Fumigants, Nitrites, Ecology.
Nitrification in Lima loam, pH 7.2, was not affected by continuous exposure of the
soil to 0.5 ppm of S02 or to brief exposures to higher S02 levels. Such treat-
ment did not increase the levels of soluble K, Mg, Ca, Mn, Fe, and Al. Intermit-
tent exposure of Hudson silty clay loam, pH 5.0, to S02 reduced the rate of
nitrate formation. Continuous fumigation of Lima loam with 5 ppm NO2 inhibited
the rate of ammonium disappearance, led to greater rates of nitrate formation,
and resulted in nitrite accumulation'. Nitrite at a level of 30 micrograms N/g
of soil also reduced the rate of ammonium disappearance. The results demonstrated
that nitrification in certain soil could be inhibited in areas acutely polluted
with S02 and NO2.
199
-------
78:05B-055
ZINC AND CADMIUM CONTENTS OF AGRICULTURAL SOILS AND CORN IN NORTHWESTERN
INDIANA,
Pietz, R.I., Vetter, R.J., Masarik, D., and McFee, W.W.
The Metropolitan Sanitary District of Greater Chicago, Canton, Illinois,
Research and Development Laboratory.
Journal of Environmental Quality, Vol. 7, No. 3, p 381-385, July-September,
1978. 1 fig, 3 tab, 26 ref.
Descriptors: Heavy metals, Soil contamination, Environmental effects, Crop
response, Pollutants, Zinc, Cadmium, Industrial plants, Urbanization, Corn
(field).
Soil and corn (Zea mays L.) leaf and grain samplings were conducted in
northwestern Indiana to determine if airborne heavy metal particulates con-
taining Cd and Zn from the northwestern Indiana industrial-urban complex,
situated on the south side of Lake Michigan, were contaminating soils and crops.
Sampling in the region revealed no widespread metal contamination. Some metal
enrichment had occurred on agricultural soils in Gary and East Gary, Indiana.
Corn leaf concentrations of Cd, Pb, and Zn fluctuated with sampling location,
but grain Cd and Pb levels remained essentially constant at <0.05 and <0.4
microgram/gram, respectively. A comparison of Zn/Cd ratios in soils, and in
corn leaves and grain, suggested that Cd was more actively accumulated in the
corn plant but not the grain. Because of the limited acreage affected and the
relatively low metal levels observed, no human or animal health problems are
expected from harvested crops or silage. The use of log distance vs. log metal
concentration in regression analysis showed that the limited metal contamination
of agricultural soils was mainly in a southeasterly direction from the industrial-
urban area.
78:05B-056
PERSISTENCE AND FACTORS AFFECTING DISSIPATION OF MOLINATE UNDER FLOODED RICE
CULTURE,
Deuel, L.E., Turner, F.T., Brown, K.W., and Price, J.D.
Texas A & M University, College Station, Department of Soil and Crop Science.
Journal of Environmental Quality, Vol. 7, No. 3, p 373-377, July-September,
1978. 2 fig, 5 tab, 7 ref.
Descriptors: Pesticides, Persistence, Return flow, Degradation (decomposition),
Microbial degradation, Pesticide residues, Submergence, Rice, Oxidation-reduction
potential, Water pollution.
Pesticides, essential for the economical production of rice (Oryza sativa L.),
could pose a serious problem if transported to surface impoundments and estuaries
along the Gulf Coast via the return flow associated with flooded rice culture.
Field experiments were conducted under flooded rice cultivation to determine per-
sistence and half-life of molinate (S-ethyl-hexahydro-1-H-azepine 1-lcarbothioate).
Persistence and half-life were evaluated with respect to intermittent and con-
tinuous flow irrigation schemes at normal and excessive application rates of 3.4
and 11.2 kg/ha molinate, respectively. Persistence at statistically significant
levels ranged from 96 to 384 hours following the application, and generally was
more a function of the application rate than irrigation scheme. Half-life values
averaged 96 ± 22 hours in intermittent flow plots, and 54 ± 17 hours in continuous
flow plots over the 3-year experiment. Application rate had little effect on half-
life. Best fit analysis of field data to the first order biological decay equation
and laboratory studies under flooded soil conditions suggested that biological
degradation was the principle mode by which molinate was dissipated in the field
experiment.
78:058-057
EVALUATING THE ENVIRONMENTAL CONSEQUENCES OF GROUNDWATER CONTAMINATION 1. AN OVER-
VIEW OF CONTAMINANT ARRIVAL DISTRIBUTIONS AS GENERAL EVALUATION REQUIREMENTS,
Nelson, R.W.
BCS Richland, incorporated, Washington, Department of Scientific Systems.
Water Resources Research, Vol. 14, No. 3, p 409-415, June, 1978. 8 fig, 1 tab,
9 ref.
200
-------
Descriptors: *Groundwater, *Water pollution, *Path of pollutants, *Environmental
effects, Model studies, Mathematical models, Equations, Pollutants, Soil contami-
nation, Groundwater movement, Water pollution sources.
\
The environmental consequences of subsurface contamination problems can be
evaluated completely and effectively by fulfilling the following five requirements:
(1) determining each present or future outflow boundary of contaminated ground-
water, (2) providing the location/arrival time distributions, (3) providing the
location/outflow quantity distributions, (4) providing these distributions for each
individual chemical or biological constituent of environmental importance, and
(5) using the arrival distribution to determine the quantity and concentration
of each contaminant that will interface with the environment as time passes. The
arrival distributions on which these requirements are based provide a reference
point for communication among scientists and public decision makers by enabling
complicated scientific analyses to be presented as simple summary relationships.
78:05B-058
EVALUATING THE ENVIRONMENTAL CONSEQUENCES OF GROUNDWATER CONTAMINATION 2. OBTAIN-
ING LOCATION/ARRIVAL TIME AND LOCATION/OUTFLOW QUANTITY DISTRIBUTIONS FOR STEADY
FLOW SYSTEMS,
Nelson, R.W.
BCS Richland, Incorporated, Washington, Department of Scientific Systems.
Water Resources Research, Vol. 14, No. 3, p 416-428, June, 1978. 11 fig, 3 tab,
20 ref.
Descriptors: *Groundwater, *Water pollution, *Path of pollutants, *Model studies.
Mathematical models. Environmental effects, Equations, Pollutants, Soil contamina-
tion, Groundwater movement, Water pollution sources.
A steady, two-dimensional flow system was used to demonstrate the application of
location/arrival time and location/outflow quantity curves in determining the
environmental consequences of groundwater contamination. The subsurface geologic
and hydrologic evaluations needed to obtain the arrival results involve a sequence
of four phases: system identification, new potential determination, flow system
kinematics, and contaminant transport analysis. Once these phases are completed,
they are summarized effectively and easily used to evaluate environmental conse-
quences through the arrival distributions.
78:058-059
EVALUATING THE ENVIRONMENTAL CONSEQUENCES OF GROUNDWATER CONTAMINATION 3. OBTAIN-
ING CONTAMINANT ARRIVAL DISTRIBUTIONS FOR STEADY FLOW IN HETEROGENEOUS SYSTEMS,
Nelson, R.W.
BCS Richland, Incorporated, Washington, Department of Scientific Systems.
Water Resources Research, Vol. 14, No. 3, p 429-440, June, 1978. 9 fig, 1 tab,
8 ref.
Descriptors: *Water pollution, *Groundwater resources, *Contaminant arrival
distributions, Groundwater movement, Hydrology, Environmental effects, Grpundwater
recharge, Mathematical models, Steady flow.
The versatility of the new contaminant arrival distributions for determining
environmental consequences of subsurface pollution problems is demonstrated through
application.to a field example involving land drainage in heterogeneous porous
materials. Though the four phases of the hydrologic evaluations are complicated
because of the material heterogeneity encountered in the field problem, the
arrival distributions still effectively summarize the minimal amount of data re-
quired to determine the environmental implications. 'These arrival distributions
yield a single graph or tabular set of data giving the consequences of the subsur-
face pollution problems. Accordingly, public control authorities would be well
advised to request that the results of subsurface pollution investigations be
provided in the form of arrival distributions and the resulting simpler summary
curve or tabulation. Such an objective is most easily accomplished through com-
pliance with the requirements presented by Nelson for assuring a complete sub-
surface evaluation.
201
-------
78:05B-060
EVALUATING THE ENVIRONMENTAL CONSEQUENCES OP GROUNDWATER CONTAMINATION 4. OB-
TAINING AND UTILIZING CONTAMINANT ARRIVAL DISTRIBUTIONS IN TRANSIENT FLOW SYSTEMS,
Nelson, R.W.
BCS Richland, Incorporated, Washington, Department of Scientific Systems.
Water Resources Research, Vol. 14, No. 3, p 441-450, June, 1978. 10 fig, 4 tab,
4 ref.
Descriptors: *Water pollution, *Groundwater contamination, Groundwater resources,
Groundwater movement, Hydrology, Environmental effects, Groundwater recharge,
Mathematical models, Transient flow system.
The versatility of the new contaminant arrival distributions for determining
environmental consequences of subsurface pollution problems is demonstrated
through application to a transient flow system. Though some of the four phases
of the hydrologic evaluations are more complicated because of the time dependence
of the flow and input contaminant concentrations, the arrival distributions still
effectively summarize the data required to determine the environmental implica-
tions. These arrival distributions yield two graphs or tabular sets of data giving
the consequences of the subsurface pollution problems in a simple and direct form.
Accordingly, the public control authorities would be able to use these results
to choose alternatives or to initiate corrective actions, depending on the indi-
cated environmental consequences.
78:05B-061
PREDICTIONS OF HEAT AND MASS TRANSFER IN OPEN CHANNELS,
Rastogi, A.K., and Rodi, W.
Karlsruhe University, West Germany.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY3, Proceedings Paper 13639, p 397-420, March, 1978. 6 fig, 24 ref, 2 append.
Descriptors: *Mass transfer, *Heat transfer, *0pen channels, *Model studies,
Effluents, Turbulence, Dispersion, Cooling water, Buoyancy, Fluid flow, Froude
number.
The paper described a three-dimensional model for calculating the distribution of
velocity, temperature, and pollutant concentration in open channel flows, and a
depth-averaged two-dimensional version for situations with insignificant stratifi-
cation and secondary currents. Both models .were restricted to parabolic flows,
where influences cannot be transmitted upstream. The turbulent stresses and heat
concentration fluxes appearing in these equations were determined from the so-
called k-epsilon turbulence model that solves differential transport equations
for the turbulence kinetic energy k and the rate of its dissipation epsilon. In
the depth-averaged model, the bottom shear stress surface heat flux and turbulence
production due to bottom shear stress are accounted for by source/sink terms in
the relevant equations. The 3D calculations compared favorably with available
measurements. The 2D and 3D predictions agreed well for high Froude numbers; for
a Froude number of 5 they agreed only for the rough bed, while for the smooth bed
they start to deviate significantly at a Froude number of 10.
78:058-062
CASING DEPTHS AND SOLUTE TRAVEL TIMES TO WELLS,
Kirkham, D., and Sotres, M.O.
Iowa State University, Ames, Department of Agronomy.
Water Resources Research, Vol. 14, No. 2, p 237-243, April, 1978. 7 fig, 9 ref.
Descriptors: *Travel time, *Solutes, *Well casings, Flow nets, Flow rates, Water
pollution sources, Water wells, Aquifers, Path of pollutants.
Partially-penetrating well casing may offer some protection against chemical solutes
such as nitrates and acids from agriculture industry, strip mines, sanitary land-
fills or other pollution sources near wells. Travel times for solutes depend on
the well and aquifer geometric factors such as well and aquifer geometric factors
such as well radius, screened length of the well, and thickness of the aquifer.
The longest and shortest travel times and flow nets were computed for 18 well-
aquifer geometries assuming piston flow in a steady state along streamlines in a
phreatic (water-table) aquifer and a fixed radius of influence. Dimensionless
202
-------
travel time t1, increases as the impervious well casing length increases. Multi-
plication of t' by a factor (p/KH) times b squared gives the real travel'time,
where f is aquifer porosity, K is conductivity, H is the difference in head
between the water table level and the level in the pumped-down well, and b is the
radius of influence. These travel times should be useful in well design and pro-
tection from solutes. Curves of t1 versus 4/b, where r is horizontal distance
from the well center to a point on top of the aquifer were given for a number of
geometries.
78:05B-063
PHOSPHORUS—A POTENTIAL NONPOINT SOURCE POLLUTION PROBLEM IN THE LAND AREAS
RECEIVING LONG-TERM APPLICATION OF WASTES,
Reddy, K.R,, Khaleel, R., Overcash, M.R., and Westerman, P.W.
North Carolina State University, Raleigh, Department of Biological and Agricultural
Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference p 193-
211. 7 fig, 7 tab, 29 ref, 3 equ.
(See 78:05A-017)
78:05B-064
THE PATE OF NITRATE IN SMALL STREAMS AND ITS MANAGEMENT IMPLICATIONS,
Robinson, J.B., Whiteley, H.R., Stammers, W., Kaushik, N.K., and Sain, P.
Guelph University, Guelph, Ontario, Canada, Department of Environmental Biology.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 247-
259. 6 fig, 2 tab, 20 ref.
Descriptors: Nitrates, Nitrogen, Water pollution, Water quality, Nitrogen cycle,
Streams, Laboratory tests, Management, Denitrification, Nutrient removal.
The present paper is a continuation of earlier investigations conducted by the
authors on nitrogen transformations in'stream-sediment-water systems. This paper
provides further evidence for significant amounts of nitrogen loss during transport
in streams and indicates the stream management options which should enhance the
process.
78:05B-065
AN APPROACH TO WATER RESOURCES EVALUATION OF NONPOINT SOURCES FROM SILVICULTURAL
ACTIVITIES—A PROCEDURAL HANDBOOK,
Currier, J.B., Siverts, L.E., and Maloney, R.C.
Watershed Systems Development Group, United States Department of Agriculture—
Forest Service, Fort Collins, Colorado.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 271-
280. 1 fig, 1 ref.
Descriptors: Water pollution control, Water pollution sources, Forest watersheds,
Forest management, Soil erosion, Streamflow, Sediment discharge, Dissolved oxygen,
Methodology.
This handbook provided an analysis methodology that can be used to describe and
evaluate the changes to the water resource due to nonpoint sources from silvi-
cultural activities. It covered only the pollutant generation and transport
processes and did not consider the economic, social and political aspects of
pollution control. It provided quantitative techniques for estimating potential
changes in streamflow, surface erosion, mass wasting, -total potential sediment
discharge, and temperature. Qualitative discussions of the impacts of silvicultural
activities on dissolved oxygen, organic matter, nutrients, and introduced chemicals
were also included. A control section provided a list of demonstrated effective
control practices and a methodology to be used to select mixtures of these con-
trols for the prevention and mitigation of water resource impacts. Such mixtures
are the technical basis for formulating "Best Management Practices" (BMP's).
Because economic, social, and political analyses were not discussed in this chap-
ter, the resulting mixtures of controls are not BMP's.
203
-------
78:056-067
NONPOINT SOURCES: STATE-OF-THE-ART OVERVIEW,
Sweeten, J.M., and Reddell, D.L.
Texas A and M University, College Station.
Transactions of the American Society of Agricultural Engineers, Vol. 21, No. 3,
p 474-483, May-June, 1978. 3 fig, 2 tab, 62 ref.
Descriptors: *Water pollution sources, *Pollutants, *Nonpoint pollution sources,
Agriculture, Nutrients, Nitrogen, Biochemical oxygen demand, Chemical oxygen
demand, Farm wastes, Water pollution.
During the past few years, the term nonpoint pollution source has become ex-
ceedingly important to agriculture. In 1972, Federal legislation (Public
Law 92-500) was passed bringing many forms of agriculturally related nonpoint
pollution under regulatory authority. Section 208 of Public Law 92-500 created
a cooperative local/state/Federal system for areawide water quality planning.
Nonpoint pollution sources are a major concern to these Section 208 planners.
During the past, both basic and applied research have been conducted on such
classical soil and water conservation topics as erosion control, sediment tran-
sport, soil chemistry and physics, crop production, range management, agricultural
chemicals, animal science, and forestry. The challenge today is to locate,
interpret, and compile this past knowledge into forms useful for Section 208
planners. This paper reviewed the current knowledge concerning the occurrence
of nonpoint pollution sources such as sediment, nutrients, pesticides, and fecal
contaminants. Sediment transport equations were reviewed and described, and the
pollution potential of range and pasture livestock production was discussed.
78:050-068
SEDIMENT AND NUTRIENT CONTRIBUTIONS TO THE MAUMEE RIVER FROM AN AGRICULTURAL
WATERSHED,
Nelson, D.W., Monke, E.J., Bottcher, A.D., and Sommers, L.E.
Purdue University, West Lafayette, Indiana, Department of Agronomy.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 491-
505. 1 fig, 9 tab, 8 ref.
Descriptors: Sediment discharge. Sediment load, Nutrient removal, Agricultural
watersheds, Agricultural runoff. Sediment transport, Water pollution, Water
quality, Water pollution sources, Indiana.
Total amounts of water, sediment, and nutrients discharged from two subwatersheds
of the Black Creek study area (5000 ha) Allen County, Indiana, were determined
during 1975 and 1976. Above average precipitation was experienced during 1975,
whereas 1976 was unusually dry. From 400 to 3700 kg of sediment/ha/yr was lost
from the subwatersheds; land slope being the dominant factor in soil loss during
the wet year and land use being the primary factor in drier year. Most of the
total P transported was sediment-bound P, whereas a substantial proportion to
total N in discharge water was nitrate. A few large rainfall events contributed
to the transport of a high proportion of sediment and sediment-bound nutrients;
whereas snow melt runoff accounted for disproportionally high transport of soluble
nutrients. Surface runoff was the major source of sediment, sediment-bound
nutrients, ammonium N and soluble organic N and P transported from the subwater-
sheds. A substantial proportion of soluble inorganic P was derived from septic
tank effluent in one subwatershed. The relationship between fertility practices
in the subwatersheds and quality of water being discharged was discussed. It
was concluded that the effects of agricultural nonpoint source pollution and
point source pollution on our water resources-are sufficiently different that
direct comparisons between them cannot be made.
204
-------
SECTION XXII
WATER QUALITY MANAGEMENT AND PROTECTION
EFFECTS OF POLLUTION (GROUP 05C)
78:05C-001
EFFECTS OF EVAPORATIVE SALT WATER COOLING TOWERS ON SALT DRIFT AND SALT
DEPOSITION ON SURROUNDING SOILS,
Wiedenfeld, R.P., Hossner, L.R., and McWilliams, E.L.
Texas A & M University, College Station, Texas Agricultural Experiment Station
Journal of Environmental Quality, Vol. 7, No. 2, p 293-298, April-June, 1978.
Descriptors: Cooling towers, Saline water, Saltation, Drifting (aquatic),
Environmental effects, Texas.
Five salt water cooling towers recently constructed near Galveston Bay, Texas,
have been shown to contribute to salt deposition in the surrounding area.
Levels as high as 1,200 kg/ha per year of total salt were encountered within
100 m of the towers, but decreased in a logrithmic fashion with distance to
<300 kg/ha per year at 434 m with only 16% attributable to the cooling towers.
The remaining deposition was caused by natural sea spray which varies widely
but averages about 250 kg/ha per year in the study area. Changes in composition
of air-borne salts with distance from the cooling towers were noted, primarily
as a narrowing of the Na/Ca ratio. Salinity levels in the soil are in equili-
brium with naturally deposited salts. Enhanced salt deposition levels due to
the cooling towers initially caused only slight effects in the soils closest
to the towers, but may eventually lead-to both salinization and solonization
in the surrounding vicinity.
78:05C-002
ON THE ESTIMATION OF THE ANTHROPOGENIC POLLUTION EFFECT ON THE FUNCTION STATE
OF THE SOIL MICROFLORA,
Gaponyuk, E.I., and Kobzev, V.A.
Institute of Experimental Meteorology, Obninsk, Union of Soviet Socialist
Republics.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
P 86-97. 2 fig, 2 tab, 13 ref.
Descriptors: Industrial wastes, Agricultural chemicals, Pesticides, Pesticide
toxicity, Environmental effects, Pollutants, Soil microorganism. Soil micro-
biology, Estimating.
Experiments were conducted in Russia to estimate the anthropogenic pollution
effect on the functional state of the soil microflora. The dehydrogenase
activity was chosen as a criterion for evaluating the effect of industrial and
agricultural toxicants on the biological activity of soil microflora. The
toxic effect of high concentrations of heavy metals in soils of industrial
regions was found to be greater than that of pesticides. The experimental re-
sults indicate that the toxic effect of chlororganic pesticides on the soil
microflora may be accounted for by the disturbance of the dehydration processes
which are of energetical value for the cell. And the decrease in the dehydrogenase
activity may lead to a decrease in the biotransformation processes associated
with it.
78:05C-003
INHIBITION OF PHOTOSYNTHESIS AND NITROGEN FIXATION IN ALGAE BY VOLATILE NITROGBN
BASES,
Hosier, A.R.
Agricultural Experiment Station, Fort Collins, Colorado.
205
-------
Journal of Environmental Quality, Vol. 7, No. 2, p 237-240, 1978. 4 fig, 2 tab,
20 ref.
Descriptors: *Nitrogen fixation, *Anabaena subcylindrica, *Chlorella ellipsoidea,
*Ammonia, *Photosynthesis, *Amines, Aliphatic amines, Feed lots, Acetylene
reduction, Nitrogen.
Inhibitory effects of ammonia and amines on oxygen production by the green alga
Chlorella ellipsoidea and the nitrogen-fixing blue-green alga Anabaena subcy-
lindrica were studied. Objectives were to determine whether amines and ammonia
affected: (1) oxygen production in the algae as in isolated plant chloroplasts,
(2) the two algae differently, or (3) nitrogen fixation by A. subcylindrica.
Aliphatic amines (1-5 carbons) and ammonia decreased C. ellopsoidea oxygen
production by 50% at concentration of 1.2-23.5 x 10 to the minus 9th power micro-
grams free amine N/cell and 160 x 10 to the minus 9th power micrograms free
ammonia N/cell. Amine (1-6 carbons) concentrations of 3.0-248 x 10 to the minus
9th power micrograms free amine N/cell decreased. A subcylindrica oxygen pro-
duction and nitrogen fixation 50%, as estimated by the acetylene reduction tech-
nique. Reduction of A. Subcylindrica oxygen production by 50% required ammonia
concentrations of 12-2510 times greater than any single amine concentration, and
decrease of acetylene reduction by 50% required ammonia concentrations of 14-
1220 times greater. The effect of the chemicals on C. ellipsoidea was reversible
and depended on pH and free amine concentration. Algae were axenically grown
in batch culture in flasks containing Knopp's solution adjusted to pH 7.2.
78:050004
NUTRIENT RUNOFF FROM FERTILIZED AND UNFERTILIZED FIELDS IN WESTERN CANADA,
Nicholaichuk, W., and Read, D.W.L.
Research Station, Research Branch, Agricultural Canada, Swift Current,
Saskatchewan S9H 3X2.
Journal of Environmental Quality, Vol. 7, No. 4, p 542-544, October-December,
1978. 2 tab, 13 ref.
(See 78:058-044)
78:05C-005
EFFECT OF SULFUR DIOXIDE ON ALGAE,
Wodzinski, R.S., and Alexander, M.
Ithaca College, New York, Department of Biology.
Journal of Environmental Quality, Vol. 7, No. 3, p 358-360, July-September,
1978. 2 tab, 10 ref.
Descriptors: Algae, Air pollution, Photosynthesis, Aquatic environment, Acidic
soils, Air pollution effects.
Photosynthetic activity in soil of pH 7.1 was unaffected by a 10-day exposure to
0.5 ppm sulfur dioxide (S02) in air. However, the photosynthetic activity of
Anabaena flos-aquae and Chlamydomonas reinhardtii suspended in a thin layer of
medium at an initial pH of 6.0 was almost totally inhibited within 24 hours by
treatment with 1.0 ppm S02 in air. The pH of the medium decreased to 5.2 or
below during this period. If the decrease in pH was prevented by the addition
of soil or phosphate buffer, no inhibition of photosynthesis was observed. In
contrast, addition of an acidic soil to a medium of pH 4.9 offered no protection
from the adverse effects of S02. The data indicate that the decrease in pH of
samples exposed to S02 was not the sole cause of the inhibition of photosynthetic
activity.
78:05C-006
HETEROTROPHIC UTILIZATION OF ORGANIC CARBON IN AQUATIC ENVIRONMENTS,
Sayler, G.S., and Gilmour, C.M.
Tennessee University, Knoxville.
Journal of Environmental Quality, Vol. 7, No. 3, p 385-391, July-September, 1978.
12 fig, 1 tab, 22 ref.
Descriptors: Eutrophication, Aquatic environment. Bacteria, Waste water, Sewage,
Respiration, Biomass, Trophic level, Water pollution, Idaho.
206
-------
Field and laboratory investigations were performed to determine the contribution
of dissolved organic carbon (DOC) to the eutrophication process and its effect on
heterotrophic bacterial activity. Results indicated growth factors or vitamin
limitations "Occurred in some aquatic samples-. Significant responses to hetero-
genous carbon substrates were detected at substrate concentrations commonly
occurring in pristine, low DOC waters. A direct linear relationship existed
between heterotrophic activity and the concentration of available DOC. Assuming
no deficiency in other essential nutrients, the DOC concentration was shown to
regulate the rate and net response of heterotrophic bacterial growth and activity
in aquatic environments. DOC levels were found to reflect net trophic conditions
unique to individual sampling locations, thereby lending itself to assays for
eutrophication assessment and pollution.
78:05C-007
THE IMPACT OF BROADLY APPLIED EFFLUENT PHOSPHORUS STANDARDS ON EUTROPHICATION
CONTROL,
Gakstatter, J.H., Bartsch, A.F., and Callahan, C.A.
United States Environmental Protection Agency, Corvallis Environmental Reseach
Laboratory, Corvallis, Oregon 97330.
Water Resources Research, Vol. 14, No. 6, p 1155-1158, December, 1978. 1 fig,
18 ref, 1 equ.
Descriptors: Eutrophication, Sewage effluents, Effluents, Phosphorus, Municipal
wastes, Sewage disposal, Model studies, Trophic level, Water quality.
The potential trophic benefits to lakes and reservoirs of a 1 mg/1 and zero-
discharge total phosphorus effluent standard for municipal sewage treatment plants
were examined by using two phosphorus mass balance models. The analysis included
255 lakes and reservoirs receiving municipal sewage treatment plant effluents and
located in the eastern half of the United States. These water bodies, their
significant tributaries, and contributing effluents were sampled during the U.S.
Environmental Protection Agency's National Eutrophication Survey. Improvement in
trophic condition is defined as a predicted decrease of at least 25% in external
phosphorus supply, which would cause the predicted in-lake total phosphorus con-
centration to (1) decrease from greater to less than 40 micrograms/liter but
remain above 20 micrograms/liter, (2) decrease from above 20 micrograms/liter to
less than 20 micrograms/liter, or (3) decrease from less than 20 micrograms/liter
to a lower concentration. Using the definition stated above, the two models in-
dicated that 18-22% of the water bodies would benefit from a 1 mg/1 effluent
standard. If the requirement were zero phosphorus, 28% of the water bodies would
benefit.
207
-------
SECTION XXIII
WATER QUALITY MANAGEMENT AND PROTECTION
WASTE TREATMENT PROCESSES (GROUP 05D)
78:050-001
EXTRACTABILITY OF 238PU AND 242 CM PROM A CONTAMINATED SOIL AS A FUNCTION OF PH
AND CERTAIN SOIL COMPONENTS: HN03-NaOH SYSTEM,
Nishita, H., Hamilton, M., and Steen, A.J.
California University, Los Angeles, Laboratory of Nuclear Medicine and Radiation
Biology.
Soil Science Society of America Journal, Vol. 42, No. 1, p 51-56, January-
February, 1978. 3 fig, 3 tab, 37 ref.
Descriptors: Soil contamination, Pollutants, Radioactivity, Nitrates, Organic
matter. Iron oxides, Hydrogen ion concentration, Silica, Ion exchange, Sorption.
The study involved an equilibrium batch technique using HN03-NaOH extracting
system. The influence of various soil components on 238Pu and 242Cm extract-
ability was determined indirectly by selectively removing them from the soil.
Soil organic matter, free iron oxides, and free silica, alumina, and amorphous
alumino-silicates influenced the chemical e'xtractability of 238Pu and 242Cm.
The influence of these soil components depended on the pH of the soil suspension.
Below pH close to 4.5, 238Pu appeared to be more strongly sorbed on the mineral
fraction of the soil than 242Cm, but above pH close to 4.5, both were strongly
sorbed on the mineral fraction. With the contaminated virgin soil, the 238Pu and
242Cm extractability ranged from 4.82 to 53.05% and 0.15 to 64.58% of dose,
respectively, depending on the pH of the extracting solution. The lowest ex-
tractability occurred around pH 7.1 for 238Pu and in the range of pH 4.7 to 5.6
for 242Cm.
208
-------
SECTION XXIV
WATER QUALITY MANAGEMENT AND PROTECTION
•
WATER QUALITY CONTROL (GROUP 05G)
78:05G-001
EFFECTS OF WETTING AGENTS ON WATER INFILTRATION INTO WATER-REPELLENT COAL
MINE SPOILS,
Miyamoto, S.
Texas A & M University, El Paso, Research Center.
Soil Science,"vol. 125, No. 3, p 184-187, 1978. 3 tab, 9 ref.
Descriptors: *Surfactants, *Wetting, *Strip mine wastes, "Infiltration, •
*Sulfonates, Spoil banks, Revegetation, Ethers, Alcohols, Effects.
Improved water infiltration may enhance revegetation of water repellent coal
mine spoils. Commercially available wetting agents, therefore, were studied
for their effect on increasing infiltration. The tested wetting agents
included linear sulfonate (anionic), alkyl polyethylene glycol ether (nonionic),
and ethoxolated alcohol (nonionic) compounds. The infiltration tests'were
performed under greenhouse conditions for soil as well as water applied wetting
agents. Results indicated that in both cases the sulfonate compound, but not
necessarily the other, improves infiltration.
78:05G-002
PREVENTION OF NITRATE LEAKAGE FROM THE HULA BASIN, ISRAEL: A CASE STUDY IN
WATERSHED MANAGEMENT,
Avnimelech, Y., Dasberg, S., Harpaz, A., and Levin, I.
Technion-Israel Institute of Technology, Haifa (Israel), Department of Agri-
cultural Engineering.
Soil Science, Vol. 125, No. 4, p 233-239, April, 1978. 4 fig, 2 tab, 17 ref.
Descriptors: *Watershed management, *Nitrates, *Leakage, Leaching, Nitrification,
Drainage effects, Water table, Sprinkler irrigation, Organic soils, Crops.
Drainage of the Hula basin led to the exposure of about 2,000 ha of organic soils.
Corollary to a high subsidence rate, extensive nitrification and leaching of
nitrates became evident, endangering the quality of the water in Lake Kinneret
(Sea of Galilee). The problem is being solved by (1) improving the drainage
system and reducing water flow through the basin; (2) maintaining a relatively
high water table during the summer, thus minimizing the depth of the oxidized
layer; (3) inducing denitrification through the use of sprinkler irrigation; and
(4) selecting crops that reduce the accumulation of nitrates in the soil.
78:05G-003
MEASUREMENT OF SEDIMENT CONTROL IMPACTS ON AGRICULTURE,
Wade, J.C., and Heady, E.G.
Arizona University, Tucson, Department of Agricultural Economics.
Water Resources Research, Vol. 14, No. 1, p 1-8, February, 1978. 2 fig, 5 tab,
13 ref.
Descriptors: *Sediment control, *Water pollution control, "Agriculture, *Measure-
ment, Optimization, Linear programming, Land use, Mathematical models, Equations,
Systems analysis.
Environmental policy has been explicitly expanded in order to consider nonpoint
or dispersed sources of water pollutants. This study utilizes a national agri-
cultural model to evaluate hypothetical policies of sediment control viewing the
problem as primarily a national one of agricultural land use. A sediment sector
is added to the basic Center for Agricultural and Rural Development National
209
-------
Water Assessment model to test the impacts of sediment control policies on the
agricultural production system. Costs of alternative control policies are
analyzed; these costs are defined as the additional costs to agriculture of
several alternative sediment'control policies. Using linear programming, the
minimum cost of the minimum feasible total sediment load is determined, a
single restraint imposed at the national level.
78:05G-004
PLANNING DIFFUSE POLLUTION CONTROL: AN ANALYTICAL FRAMEWORK,
Schneider, R.R.
Williams College, Williamstown, Massachusetts, Department of Economics.
Water Resources Research, Vol. 14, No. 2, p 322-336, April, 1978. 4 fig, 2
tab, 39 ref.
Descriptors: *Planning, *Water pollution control, Benefits, Costs, Analytical
techniques, Agriculture, Optimum development plans, Systems analysis, Evaluation.
Determination of an optimal nonpoint pollution control strategy demands informa-
tion relating to (1) costs of pollutant reduction; (2) transport of pollutants;
(3) water quality impact of pollutants; and (4) the economic impact of water
quality changes. This paper briefly reviews the literature in each of these
areas and suggests an analytical framework useful in the development of an
optimal nonpoint pollutant control strategy.
78:050-005
OVERVIEW OF NITROGEN IN IRRIGATED AGRICULTURE,
Rauschkolb, R.S.
California University, Davis, Cooperative Extension.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 53-60, May 15-
18, 1978. 3 ref.
Descriptors: Water quality. Nitrogen, Pollution abatement, Pollutant identifica-
tion, Fertilization, Water management (applied),Irrigated land, Water law.
Events of the recent past have been moving agriculture rapidly towards the
point where it can no longer afford the luxury of being concerned with production
of food and fiber alone. One of the principle reasons for the change in atti-
tudes has been the Federal Water Pollution Control Act Amendment of 1972,
commonly referred to as Public Law 92-500. Within this law there is a section
dealing with areawide planning, Section 208. Under this section each state is
to develop waste water management strategies which indicate methods for control
or treatment of all point and nonpoint sources of pollution within an area.
Specific outputs resulting from Section 208 area-wide planning include a regu-
latory program to control or treat all point and nonpoint pollution sources,
including in-place or accumulated pollution sources. This represents only one
of the many outputs that are expected from area 208 planning, but it is one
that seems to be the most important with respect to nitrogen management in
irrigated agriculture.
78:05B-006
ECONOMIC IMPACTS OF CONTROLLING NITROGEN CONCENTRATION AND OTHER WATER QUALITY
DETERMINANTS IN THE YAKIMA RIVER BASIN,
Pfeiffer, G.-H., and Whittlesey, N.K.
North Dakota State University, Fargo, Department of Agricultural. Economics.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 415-422, May 15-
18, 1978. 4 fig, 4 tab, 9 ref, 2 equ.
Descriptors: Water quality, Nitrogen, Economic impact, Return flow, Pollution
abatement.
The nonpoint source nature of water quality degradation caused by irrigation
return flows makes control nearly impossible with traditionally effective
measures, such as limitations or taxes on effluents. As a consequence, control
or taxation of those inputs to production which are involved in effluent input-
output relationships is a possible alternative. In the Yakima River Basin, three
210
-------
determinants of river water quality were identified: nitrogen concentration,
river water temperature, and soil erosion by irrigation water. Among the
pollution control policies considered for effectiveness, producer cost, and
social cost were taxation of nitrogen fertilizer, increasing the charge for
irrigation water, reduction of irrigation water rights, and restrictions on the
types of irrigation systems used. Results showed that policies which affect the
level of one pollutant may or may not significantly affect the levels of others.
Furthermore, policies taxing or charging for inputs, such as fertilizer and
irrigation water, cause a substantial reduction in producer income if acceptable
water quality is to be attained. Therefore, water quality policy formulation
and evaluation should consider the interactions which exist among water quality
determinants and considerations of both the expected benefits of improved water
quality and the level and distribution of improvement costs.
78:05G-007
SOURCES OF NITROGEN FOR CROP UTILIZATION,
Murphy, L.S.
Potash/Phosphate Institute, Manhattan, Kansas, Great Plains Director.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 61-107, May 15-
18, 1978. 23 tab, 40 ref, 2 equ.
Descriptors: Nitrogen, Fertilizers, Crop production, Nitrogen fixation, Corn
(field), Soybeans, Alfalfa, Symbiosis, Ammonium compounds, Irrigation water.
Nitrogen fertilization of crops is essential for maximum food production.
Nitrogen from organic matter in the soil declines with continued cultivation
to the point that supplemental nitrogen applications are necessary. Supplemental
sources of nitrogen for crop production include symbiotically fixed nitrogen
from legumes, nonsymbiotically fixed nitrogen from free-living organisms in
the soil, inorganic nitrogen from lightning discharges and industrial emissions,
industrially fixed nitrogen and nitrogen from various waste products. Recommenda-
tions for nitrogen applications in either dryland or irrigated agriculture are
based on crop need as determined by agricultureJ- research. Soil analysis is an
important tool in determination of needs. Use of present and future recommenda-
tions will both maximize production of food and maintain environmental quality.
78:05G-008
NITROGEN FORMS AND CYCLING IN RELATION TO WATER QUALITY,
Menzel, R.G.
Water Quality Management Laboratory, Science and Education Administration, U.S.
Department of Agriculture, Durant, Oklahoma 74701.
Descriptors: Water quality, Nitrogen, Nitrogen compounds, Nitrogen cycle,
Nitrogen fixation, Denitrification, Eutrophication.
The intended use of water determines the significance of various forms of
nitrogen in water quality. Upper limit concentrations have been recommended for
several forms of nitrogen in water used for public water supplies, freshwater
aquatic life, marine aquatic life, and agricultural uses. The concentrations
are lowest for cyanide, and increase in the order ammonium, nitrite, and nitrate.
Nevertheless, nitrate is more often of concern in water quality than are the first
three forms of nitrogen. Much of the total nitrogen in surface waters occurs in
particulate or dissolved organic forms. Plant growth is often excessive when
the total nitrogen concentration exceeds 0.5 mg/1 if other nutrients are ade-
quately supplied and growth conditions are favorable. Nitrogen supply limits
growth in many ocean areas and in a few lakes, mainly eutrophic ones. Nitrogen
fixation by blue-green algae tends to correct nitrogen deficiencies. Denitrifi-
cation by bacteria tends to correct excesses. These features indicate that high
nitrogen concentrations may be an effect, rather than a cause, of eutrophication.
78:05G-009
EVALUATION OF IRRIGATION METHODS FOR SALINITY CONTROL IN GRAND VALLEY,
Evans, R.G., Walker, W.R., Skogerboe, G.V., and Smitft, s.w.
211
-------
Colorado State University/ Fort Collins, Department of Agricultural and
Chemical Engineering.
Descriptors: Irrigation, Salinity, Saline soils, Water quality, Water loss,
Water pollution.
Irrigation return flows in the Upper Colorado River carry large salt loads as a
result of contact with the saline soils and the marine derived geologic substra-
tum. The Grand Valley of western Colorado is a major contributor to the salinity
problems of the basin and is, therefore, a logical region to test the effective-
ness of agricultural salinity control alternatives. This study emphasized the
implementation of on-farm salinity control alternatives; primarily evaluating
irrigation scheduling, furrow irrigation, sprinkler irrigation, and trickle
irrigation. Border irrigation was also evaluated, but was not implemented as
part of this study. The cost-effectiveness of the various on-farm alternatives
in the Grand Valley is summarized and presented in this report.
78:05G-010
INTEGRATING DESALINATION AND AGRICULTURAL SALINITY CONTROL ALTERNATIVES,
Walker, W.R.
Colorado State University, Fort Collins, Department of Agricultural and Chemical
Engineering.
Publication No. EPA-600/2-78-074, April, 1978. 182 p, 30 fig, 17 tab, 55 ref,
2 append.
Descriptors: Cost-effectiveness, Desalting, Optimization, Salinity, Sprinkler
irrigation, Water quality.
The cost-effectiveness relationships for various agricultural and desalination
alternatives for controlling salinity in irrigation return flows are developed.
Selection of optimal salinity management strategies on a river basin scale is
described as a problem of integrating optimal strategies with individual sub-
basins and irrigated valleys. Desalination systems include seven processes:
(1) multi-stage distillation; (2) vertical tube evaporation in conjunction with
(1); (3) a vapor compression form of (2); (4) electrodialysis,* (5) reverse
osmosis; (6) vacuum freezing - vapor compression; and (7) ion exchange. Agri-
cultural salinity control alternatives include conveyance linings, irrigation
scheduling, automation, sprinkler irrigation systems, and trickle irrigation
systems. A case study of the Grand Valley in western Colorado is presented to
demonstrate the analysis developed. Results indicate that treatments of the
agricultural system are generally more cost-effective than desalting except for
high levels of potential salinity control. Lateral linings and on-farm improve-
ments are the best agricultural alternatives.
78:05G-011
IMPLEMENTATION OF AGRICULTURAL SALINITY CONTROL TECHNOLOGY IN GRAND VALLEY,
Evans, R.G., Walker, W.R., Skogerboe, G.V., and Binder, C.W.
Colorado State University, Fort Collins, Department of Agricultural and Chemical
Engineering.
Publication No. EPA-600/2-78-160, July, 1978. 193 p, 62 fig, 29 tab, 46 ref.
Descriptors: Irrigation, Ditches, Irrigation canals, Salinity, Saline soils,
Salt water, Seepage, Water distribution.
A summary of the results of applied research on salinity control of irrigation
return flows in the Grand Valley of Colorado -is presented for the period of
1969 to 1976. Salinity and economic impacts are described for the Grand Valley
Salinity Control Demonstration Project which contains approximately 1,600
hectares and involves most of the local irrigation companies in the Valley.
During the eight years of the demonstration project, 12.2 km of canals were
lined, 26.54 km of laterals were lined, 16,400 meters of drainage tile were
installed, a wide variety of on-farm improvements were constructed, and an
irrigation scheduling program was implemented. On-farm improvements evaluated
were solid-set sprinklers, side-roll sprinklers, drip (trickle) irrigation,
furrow irrigation, and automatic cut-back furrow irrigation. The total value
of the constructed improvements in the demonstration area was about $750.000.
The total improvements resulted in a salt reduction of 12,300 metric tons per
year reaching the Colorado River. This salt reduction results in an annual
212
-------
benefit to downstream water users of nearly $2,000,000. In addition, there are
benefits to the local water users with increased crop yields, and to the neoole
of Grand Valley in increased business. ^ *
78:05G-012
SOCIO-ECONOMIC AND INSTITUTIONAL FACTORS IN IRRIGATION RETURN FLOW DMATTTV
CONTROL VOLUME I: METHODOLOGY, WUAi,j.ix
Vlachos, E.G., Huszar, P.C., Radosevich, G.E., Skogerboe, G.V. , and Trock W
Colorado State University, Fort Collins, Colorado 80523. '
Publication No. EPA-600/2-78-174a, August, 1978. 132 p, 21 fig, 10 tab, 32 ref.
Descriptors: Water law, Water rights, Irrigation, Irrigated land, Water pollution
W3.t61T CfUclllty •
The purpose of this study has been to develop an effective process for implement-
ing technical and institutional solutions to the problem of return flow pollution
The process developed: a) defines the problem in terms of its legal, physical
economic, and social parameters; b) identifies potential solutions in relation'
to the parameters of the problem; c) assesses potential solutions for diverse
situations; d) specifies those solutions or groups of solutions which are the
most effective in reducing pollution and are implementable. This process is
conceptualized in Volume I of the study. The general results of its application
are further presented in three separate volumes concerning the specific case
studies of Yakima Valley (Washington) , Middle Rio Grande Valley (New Mexico and
Texas) , and Grand Valley (Colorado) .
78:05G-013
SOCIO-ECONOMIC AND INSTITUTIONAL FACTORS IN IRRIGATION RETURN FLOW QUALITY CONTROL
VOLUME II: YAKIMA VALLEY CASE STUDY,
Huszar, P.C., Radosevich, G.E., Skogerboe, G.V. , Trock, W.L. , and Vlachos, E.G.
Colorado State University, Fort Collins, Colorado 80523.
Publication No. EPA-600/2-78-174b, August, 1978. 140 p, 19 fig, 12 tab, 113 ref
1 append. '
Descriptors: Water law, Water rights, Irrigation, Irrigated land, Water pollution
Water quality. ' '
The goal of this research project has been to develop an effective process for
implementing technical and institutional solutions to the problem of irrigation
return flow pollution. This report contains the findings of a case study of the
Yakima Valley, Washington. The findings are reported according to the proposed
process, namely: a) defining the problem in terms of its physical, legal, and
economic, and social parameters; b) identifying potential solutions in relation
to the key parameters of the problem; c) assessing the range of potential solutions
for the specific area of concern; and d) specifying those solutions or groups of
solutions which are most effective in reducing pollution and are implementable.
The basic conclusions of the report are that: a) irrigation methods used in many
parts of the Valley are inappropriate to the topography and soils, thus causing
return flow pollution; b) neither state nor federal water quality regulations
have had a significant impact on the pollution problem; c) a major cause of the
problem is the underpricing of irrigation water caused by the absence of economic
markets for its allocation; d) the first step in solving the problem is the
creation of an economic market to allocate irrigation water; ej perception and
demonstration of the problem are vital for any efforts to implement any solutions;
and f ) holistic thinking by farmers regarding water in the Valley and individual
acknowledgment of contributions to the problem are necessary to its solution.
78:05G-014
SOCIO-ECONOMIC AND INSTITUTIONAL FACTORS IN IRRIGATION RETURN FLOW QUALITY
CONTROL VOLUME III: MIDDLE RIO GRANDE VALLEY CASE STUDY,
Trock, W.L., Huszar, P. C. , Radosevich, G.E., Skogerboe, G.V. , and Vlachos, E.G.
Colorado State University, Fort Collins, Colorado 80523.
Publication No. EPA-600/2-78-174c, August, 1978. 137 p, 14 fig, 15 tab, 146 ref,
2 append.
Descriptors: Water law, Water rights, Irrigation/ Irrigated land, Water pollution,
Water quality.
213
-------
Degradation of water quality as a consequence of use in irrigation in the Lower
Rio Grande Valley of New Mexico is a largely unavoidable phenomenon. In this
region, annual allocations of water to irrigated farms, about 2.5 acre-feet per
acre, are little more than enough to produce crops. Evaporation and transpiration,
occurring because of irrigation, cause concentrations of salts in return flows
to be greatly increased, and the addition of these highly saline return flows
to a quite limited flow of water in the Rio Grande causes the quality of the
river water to be significantly reduced. It is possible to affect the quantity
and quality of return flows by improvement of water transport facilities (canals,
laterals and ditches) and by improved management of water on some farms. These
two technical improvements can be accomplished by extension of technical assistance
through existing federal and state agencies and by cost-sharing programs such as
the Agricultural Conservation Program. But it is also possible to achieve im-
proved management of water on farms by facilitating exchanges or sales of allot-
ments among farmers who are members of irrigation districts. Such transfers
ordinarily result in improved use of water, i.e., a more conservative use of
water and employment of this scarce input in higher-valued uses. The consequence
is some reduction in return flows and thus improvement in the quality of water
in the Rio Grande River.
78:05G-015
SOCIO-ECONOMIC AND INSTITUTIONAL FACTORS IN IRRIGATION RETURN FLOW QUALITY CONTROL
VOLUME IV: GRAND VALLEY CASE STUDY,
Skogerboe, G.V., Huszar, P.C., Radosevich, G.E., Trock, W.L., and Vlachos, E.G.
Colorado State University, Fort Collins, Colorado 80523.
Publication No. EPA-600/2-78-174d, August, 1978. 139 p, 17 fig, 14 tab, 39 ref,
2 append.
Descriptors: Water law, Water rights, Irrigation, Irrigated land, Water pollution/
Water quality.
The Grand Valley was used as a case study area for developing an effective process
for implementing technical and institutional solutions to the problem of pollution
from irrigation return flows. This area is the most significant agricultural
salt source in the Upper Colorado River Basin. The primary source of salinity
is from the extremely saline aquifers overlying the marine deposited Mancos
Shale formation. Subsurface irrigation return flows resulting from conveyance
seepage losses and overirrigation of croplands dissolve salts from this formation
before returning to the Colorado River. The most cost-effective technologies
for reducing the salt load are a combination of lateral lining and on-farm
improvements. Farmer participation in such a program is very important. Imple-
mentation will result in excess water being available for selling, renting, or
leasing to water users upstream from Grand Valley.
78:05G-016
ECONOMIC IMPACT OF WATER QUALITY ON RIVER BASIN MANAGEMENT,
Helweg, O.J., and Alvarez, D.
California University, Davis, Department of Civil Engineering.
California Water Resources Center, Davis, Completion Report, Contribution 168,
March, 1978. 61 p, 47 fig, 16 tab, 47 ref.
Descriptors: *Groundwater, *Irrigation, *Water quality, *Water costs, 'Economic
impact, California, *San Luis River basin (California), Irrigation practices,
Saline water, Pricing, Water demand, River basin management, Water pollution.
Groundwater quality degradation caused by irrigation affects as much as one-third
of the irrigated area of the world. This problem is particularly insidious be-
cause the process is slow and hidden. A management tool called the Accelerated
Salt Transport (ASTRAN) method has recently been proposed to help control ground-
water degradation. The ASTRAN method distributes the different qualities of
available irrigation water over the basin in a way that controls groundwater
degradation at minimum cost. To implement the solution, the water supplier must
give some irrigators poorer quality water than others. If water is sold merely
by the quantity used, irrigators who receive the poor quality water will certainly
object; consequently, the price of water should be determined by water quality as....
well as quantity. This study investigated a way to price water quality and quantify
by approximating its value with a derived demand surface. This value was then used
214
-------
In Q *u S °Ptimally distributed water. The data from the San Luis RivPr R
In southern California were used to test the results which are presented in a
series of figures along with a detailed description of the approach Ssed.
78:05G-017
NORTH CAROLINA 208 CASE STUDY,
Jrrnev' L.F., Koehler, F.A., and Bliven, L.F.
"Orth Carolina S-t-at-o TTm' TTQ vai -l-if Dala'i^Vi n^v,., »-4-m,,_ j. -f nj_i_ j , ,
or Biological and
^aper No. 78-2584, Presented at the 1978 Winter Meeting of the American
Ulinois, 6 p. 4 ref. ' , , a mer House Hotel, Chicago,
(See 7S:06E-009)
78:05G-018
EFFECT OF DRAINAGE SYSTEM DESIGN AND OPERATION ON NITRATE TRANSPORT
jKaggs, R.w., and Gilliam, J.W.
orth Carolina State University, Raleigh, Department of Biological and
Agricultural Engineering.
£aper No. 78-2501, Presented at the 1978 Winter Meeting of the American Societv
"f Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicaan
Illinois, 13 p. 9 fig, 3 tab, 18 ref, 4 equ. g '
Descriptors: Water pollution, Nitrates, Water quality, Simulation analysis,
dr tnage e^^ects, Drainage systems, Drainage density, Drainage water, Surface
Drainage, Subsurface drainage.
s^™ulations were conducted to predict N03(-) movement from artificially drained
Noi";8' Effects of alternative drainage designs and operational procedures on
3(~) outflow to drainage waters were presented.
78:05G-019
NONPOINT SOURCE CONTROL GUIDANCE, AGRICULTURAL ACTIVITIES,
•"-nronson, R.E.
^nited states Environmental Protection Agency, Washington, D.C., Water Planning
3T^S/PB~280/845, EPA-440/3-78-001, February, 1978. 147 p. 40 fig, 8 tab, 101 ref,
Water pollution, Water pollution control, Water quality, Water
control, Water pollution sources, Sediment discharge, Agricultural
" Salinity, Grazing, Waste disposal.
publication presents technical and management guidance information regarding
em identification and assessment, information needs and analyses, and best
anagement practices (BMP's) to provide state and areawide water quality management
yencies and other concerned groups with assistance in the development and imple-
entation of programs to control nonpoint sources of pollution.
78:05G-020
PPECT OF SALINITY ON AGRICULTURE IN IRAQ,
Al-Layla, M.A.
°sul University, Iraq, Department of Engineering.
ournal of the Irrigation and Drainage Division, American Society of Civil
engineers, Vol. 104, No. IR2, p 195-207, June, 1978. 2 fig, 3 tab, 3 ref, 1 append.
wa?Crlptors: Salinity, Agriculture, Irrigation effects, Return flow, Drainage
ater, Water quality control, Water pollution, Asia.
Jfffgation has progressed considerably in Iraq, but it has resulted in soil
£a-i-inity thereby reducing the productivity of the agricultural lands. Land has
wafn reclaimed by taking up drainage projects, but the discharge of the drainage
water into the river has considerably increased the salinity of the river water
fusing deterioration in its quality. The increase in salinity of river water creates
Problems for irrigation and municipal uses, and therefore, the discharge of drainage
215
-------
water to the river must be controlled. To obtain maximum benefit from the use of
land and water resources, the problems of irrigation, drainage, control of river
water quality, and education of farmers must be tackled as a whole and not in
parts.
78:05G-021
A RATIONAL APPROACH FOR OPTIMIZING APPLICATION RATES OF FERTILIZER NITROGEN TO
REDUCE POTENTIAL NITRATE POLLUTION OF NATURAL WATERS,
Singh, B., Biswas, C.R., and Sekhon, G.S.
Punjab Agricultural University, Ludhiana 141004, India, Department of Soils.
Agriculture and Environment, Vol. 4, No. 1, p 57-64, April, 1978. 3 fig, 2 tab,
6 ref.
Descriptors: Nitrogen, Fertilizers, Nitrates, Pollutants, Pollution abatement,
Water pollution control, Wheat, Sweet corn, Crop response, Leaching, Crop
production.
Yield, N uptake and residual N03(-)-N data for wheat and maize, raised in a long-
term experiment, have been discussed to determine optimum rates of fertilizer
N application at which yields are least affected, while unused nitrogen, which
is a potential pollutant, is reduced to a permissible level. Computation of
fertilizer N rates corresponding to the points of greatest economic return and
permissible N loss has been described. Optimum fertilizer N rate-is the smaller
of the two fertilizer N rates. By assuming a loss of 60 kg N/ha or less, as
environmentally permissible, it was observed that a small yield increment of
maize would have to be sacrificed for the protection of the environment? whereas,
for wheat, nitrogen can be applied safely up to the point of greatest economic
return. Coincidence of the rainy season with the growth period of maize in the
study area seems to have reduced the fertilizer N rate, corresponding to the
point of permissible N loss, lower than that for greatest economic return.
78:056-022
AGRICULTURE AND SALINITY,
Gardner, B.D., and Stewart, C.E.
Values and Choices In the Development of The Colorado River Basin, The University
of Arizona Press, Tucson, Arizona, 1978, p 121-143; 7 fig, 4 tab, 14 ref.
Descriptors: Colorado River, Colorado River Basin, Return flow, Water quality
act, Water quantity control, Water pollution control, Water pollution sources,
Salinity, Mexican water treaty.
This paper discusses the saline return flow problems of the Colorado River due
to irrigated agriculture of the Colorado River Basin.
78:05G-023
FINANCING REGIONAL DRAINAGE FACILITIES UNDER 1978 ECONOMIC CONDITIONS,
Johnston, W.R., and Beck, L.A.
Westlands Water District, P.O. Box 5222, Fresno, California 93755.
Paper No. 78-2535, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 12 p. ' 3 fig, 3 tab.
Descriptors: Drainage problems, Drainage, Financing, Saline water, Salinity,
California, Cost-benefit analysis, Crop production, Surface drainage. Subsurface
drainage.
The benefits, costs, and a recommended financial program to solve saline drainage
problems on over 400,000 hectares (1,000,000 acres) of irrigated land in the San
Joaquin Valley of California, USA, are discussed. The heed to provide long-term
financing for major drainage facilities is demonstrated.
216
-------
78:050-024
APPLICATION OF LAND TREATMENT FOR WATER QUALITY IMPROVEMENT,
Wheaton, R.2.
Purdue University, Lafeyette, Indiana, Department of Agricultural Engineering.
Paper No. 78-2533, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 3 p.
Descriptors: Water quality control, Water quality, Land management, Control
structures, Cultural control, Soil conservation, Pollution abatement, Agricultural
watersheds, Small watersheds, Water law.
Application of Land Treatment measures is considered to be a means of controlling
Agricultural Non-Point Pollution. Experiences gained during a demonstration
project of these principles is reviewed. The problems of absolute water quality
standards and monitoring for compliance of non-point pollution are discussed and
alternatives suggested.
78:05G-025
AGRICULTURAL DRAINAGE PROBLEMS IN KERN COUNTY, CALIFORNIA,
Rector, M.R., and Donnan, W.W.
Kern County Water Agency, Bakersfield, California.
Paper No. 78-2532, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-^20, 1978, Palmer House Hotel, Chicago,
Illinois, 15 p. 3 fig.
Descriptors: Drainage, Drainage area, Tile drainage, Crop production. Perched
water, Salinity, Drilling, Water quality, Water table, California.
This paper describes procedures followed in the diagnosis, monitoring and evaluation
of the drainage problem areas within. Kern County, California as a case history
for use by others who are facing these same problems.
78:05G-026
SUBSURFACE DRAINAGE SYSTEMS INSTALLATIONS IN ARID LANDS—THE STATE OF THE ART,
True, G.
Advanced Drainage Systems, Incorporated, Fresno, California, Department of
Agricultural Engineering.
Paper No. 78-2528, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 2 p.
Descriptors: Subsurface drainage, Drainage, Installation, Arid lands. Equipment,
Materials, Trenches, Grading, Maintenance, Irrigated land.
Agricultural drainage contractors are quickly adapting to new techniques and
equipment that result in better and more efficient drainage systems. The.se
relatively inexpensive drainage systems are maintaining the long-term viability
of irrigated agriculture and increasing crop yields far above the value of energy
and capital invested in drainage.
78:05G-027
DESIGN AND OPERATION OF GRADIENT TERRACE SYSTEMS,
Bondurant, D.T., and Laflen, J.M.
Soil Conservation Service, Des Moines, Iowa.
Paper No. 78-2520, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 7 p. 4 fig, 5 tab, 19 ref.
(See 78:02J-006)
78:05G-028
GROUNDWATER AND SALINITY IN THE GRAND VALLEY OF COLORADO,
United states Department of Agriculture, Science and Education Administration,
Agricultural Research, Fort Collins, Colorado.
217
-------
Paper No. 78-2530, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 21 p. 5 fig, 3 tab, 14 ref.
Descriptors: Salinity, Saline water, Saline soils, Salts, Groundwater, Water
management (applied), Colorado, Colorado River, Colorado River Basin, Structures.
This paper describes causes and magnitudes of groundwater flows and salt loading
in the Grand Valley in western Colorado. Structural measures and management
practices most likely to reduce salt loading are described.
78:05G-029
PLANT NUTRIENT LOSSES FROM FOLIAR-FERTILIZED SOYBEANS,
Baker, J.L., and Laflen, J.M.
Iowa State University, Ames, Department of Agricultural Engineering.
Paper No. 78-2084, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 11 p. 5 fig, 1 tab,
4 ref.
Descriptors: Fertilization, Nutrient removal, Nutrients, Foliar application,
Water quality, Runoff, Foliar, Soybeans, Simulated rainfall, Corn (field).
To determine the impact of foliar-fertilization of soybeans on runoff water
quality, simulated rainfall was applied to soybeans and corn receiving no
fertilizer and to soybean plots foliar-fertilized (20 kg/ha N, 2 kg/ha P) 39
and 13 hr before rainfall. Washoff water from plants and surface runoff water
were analyzed for NH4-N, N03-N, total N, PO4-P, and hydrolyzable-P. Foliar-
fertilization did initially increase concentrations of dissolved nutrients in
runoff, but most N and P washed from plants was retained by the soil within
plot areas.
78:05G-030
TRANSPORT CHARACTERISTICS OF PHOSPHORUS IN CHANNELIZED AND MEANDERING STREAMS,
Rosendahl, P.C., and Waite, T.D.
United States National Park Service, South Florida Research Center, Everglades
National Park, Homestead, Florida 33030.
Water Resources Bulletin, Vol. 14, No. 5, p 1227-1238, October, 1978. 4 fig, 1 tab,
20 ref, 7 equ.
Descriptors: Nutrients, Phosphorus, Water quality, Meanders, Channeling,
Phosphates, Surface runoff, Dispersion, Mathematical models, Plankton.
Comparisons were made between rates of movement of orthophosphate in a canal
and a meandering stream. The meander stream had greater algal and macrophyte
phosphate uptake rates, and lower plankton and sediment release rates compared
to the canal. Chemical precipitation and direct rainfall influences on
orthophosphate movement were insignificant relative to other terms. The major
source of phosphorus to both systems was from upland runoff. The impact of this
source was greater on the meandering system due to the smaller channel volume.
When secondary effects of meandering were considered such as march inundation,
the net orthophosphate movement within the meandering channel was less than that
for the canal; due to the lower concentrations of phosphorus in march effluent
waters. Field experiments were conducted to compare the longitudinal dispersion
coefficient between a canal and meandering river system; the meandering stream
had a dispersion coefficient over 17 times that measured for the canal. Rates
of orthophosphate movement were combined into a single mass transport equation,
and a numerical solution was obtained. Internal river and canal'channel processes
were overshadowed by external point source loadings.
78:05G-031
A PARTITIONING PROCEDURE FOR WATER QUALITY MANAGEMENT MODELS,
Rossman, L.A., and Vanecek, F.T.
Environmental Protection Agency, Cincinnati, Ohio.
Water Resources Bulletin, Vol. 14, No. 4, p 842-855, August, 1978. 2 fig, 2 tab,
25 ref.
218
-------
Descriptors: *Water quality, *Management, *Economic efficiency, *Partitioning
procedure, *0ptimization, Thermal pollution, Decision making, Standards, Water
temperature, River systems, Dissolved oxygen. Biochemical oxygen demand,
Mathematical mqdels, Systems analysis. Equations, Cooling levels, Stream
response. Nonlinear programming, Gradient search procedure.
An improved computational procedure for solving water quality management models
containing interacting pollutants and control policies is presented. The method
is developed with respect to the specific problem of minimizing the costs of
basin-wide thermal and organic pollution control to meet water quality standards.
It views the problem in partitioned form where a master problem is sued to find
cooling levels for thermal polluters while subproblems determine optimal organic
pollutant reductions for fixed cooling levels. A gradient-based search procedure
is used to solve the master problem. Computational results for several river
systems are presented. Application of the method to other water quality manage-
ment models should improve computational efficiency and make the use of such
models more attractive to basin planners.
IMPROVING3 IRRIGATION RETURN FLOW QUALITY WITH A WATER RENTAL MARKET,
SloradoPStatea!toi?SSty!!'Fort Collins, Department of Economics.
Water Resources Bulletin, Vol. 14, No. 4, p 978-987, August, 1978. 3 fig, 1 tab,
5 ref.
Descriptors: 'Irrigation. 'Return flow, 'Water quality, 'Improvement, 'Rental
market Water transfer Water allocation policy), River systems, Effects,
?osts%a?er pollulfon! Conceptual model , Yakima Valley (Washington), Systems
analysis.
Current policies for correcting the problem of irrigation return flow pollution
tend to ttack the symptoms of t he problem ^*™ aslhe* ou^ce
eroem wate quality benefits of altering
33 s-sass.psis j s H r%ss-^cS s^^r^^^"
and rent the surplus *°°^t,l market ciuld Improve »lter quality In the Yakima
crop production.
AN CATION OF THE POTENTIAL FOR USING DRAINAGE CONTROL TO REDUCE NITRATE LOSS
FROM AGRICULTURAL FIELDS TO SURFACE WATERS,
'4~£J!$£ 5S2SS o« Soil sc^e.
£SS£ ISJt^S P! *S SST « «S- 32 -f, 2 appen*.
„ u. j ,,4-wvi **Mtrates. 'Soil water movement, 'North Carolina,
Descriptors: /Drainage control, Citrates, Denitrification, Agricultural
Nitrogen, Agricultural soils, Surrace watej-o,
runoff, Soil drainage, Coastal plain sons.
,.v * *,v.a,Hmi<* work which revealed that considerable
This study was. an outgrowth of Pfev*°uf *f *JJs £ith high water tables. This
denitrification occurred in poorly araineu , waters than occurred in better
resulted in less nitrate leaving "~JS TV I were used: one in the poorly drained
drained soils. Two N.C. CoaBt" *£ „£,." in the moderately well drained soils of
soils of the Tidewater area and the other type water control stuctures were
the Lower Coastal Plains, ^"^f1 J^ Ration. Each control structure was
installed in four main tile lines at eacn ioc ti total outfiow of drainage
equipped with a weir and a stage x*°°™?*t installed at each weir to take
water. A semi-proportional watei .falructures were very effective in controlling
samples for chemical analyses. The struc u drained soils. The annual
the loss of nitrate-nitrogen on the moderately wex
219
-------
loss of nitrate-nitrogen under controlled conditions was 1-7 kg/ha as compared
to the 25-40 kg/ha under uncontrolled conditions. This reduction is due entirely
to prevention of water movement through the tile lines, however, and there is no
indication that the water control resulted in the anticipated increased denitrifi-
cation in the fields. Water table control on the poorly drained soils was much
more successful. By controlling and maintaining the water table at higher levels,
no significant difference in oxidation-reduction potential throughout the soil
profile was observed. Also, there was no significant change in the nitrogen
concentration in water leaving the fields in the drainage ditches under
controlled and uncontrolled conditions.
78:05G-035
SALINITY MANAGEMENT OPTIONS FOR THE COLORADO RIVER, DAMAGE ESTIMATES AND CONTROL
PROGRAM IMPACTS,
Andersen, J.C., Kleinman, A. P., Brown, F.B., Cannon, J.R., and d'Arge, R.C.
Utah Water Research Laboratory, Logan.
Water Resources Planning Series Report P-78-003, June, 1978, 344 p. 53 fig, 365
tab, 7 append.
Descriptors: *Economic efficiency, *Resource allocation, *Salinity, *Agricultural
damages, *Alternative costs, *Colorado River, Regional analysis, Water quality,
River basins, Water management (applied), Estimating, Costs, Economic impact,
Input-output analysis.
Rivers draining arid basins increase in salinity content in the downstream area of
the point where water users are often significantly damaged. The problem in some
cases can be ameliorated by altering upstream water and land use practices . An
economic trade-off exists between the cost of such upstream efforts and the down-
stream benefits achieved. This study sought to provide additional information
to estimate (1) economic and (2) economic costs of salinity control measures by
upstream water users. Damages were estimated for high salinity levels to provide
guidelines to project future conditions. Control costs were estimated with a
physical model developed to predict the response of soil, water, and crop factors.
Input-output models were used to estimate indirect economic impacts.
78:05G-036
EFFICIENT AMENDMENT USE IN SODIA SOIL RECLAMATION,
Prather, R.J., Goertzen, J.O., Rhoades, J.D., and Frenkel, H
Institute of Soils and Water, Volcani Center, P.O. Box 6, Bet Dagan, Israel.
Soil Science Society of America Journal, Vol. 42, NO. 5, p 782-786, September-
October, 1978. 8 fig, 5 tab, 9 ref. r
Descriptors: Reclamation, Alkali soils, Soil amendments, Calcium sulfate,
Gypsum, Calcium chloride, Sodium, Leaching, Regression analysis.
A laboratory column study of sodic soil reclamation was carried out using two
soils high in exchangeable sodium percentage (ESP) and cation exchange (CEC) .
Three amendments (CaS04-2H20, CaC12«2H20, and H2S04) were used singly and in
combination to test their effectiveness and efficiencies with respect to amount
of amendment, tine, and leaching needed. As a single amendment, H2S04 was found
to be more effective than CaS04 and results in a more desirable ESP profile than
CaC12. Combining either CaC12 or H2S04 with CaS04 (proportions of 1/4 and 3/4,
respectively) appreciably reduced the time and leaching needed to achieve
reclamation as compared with CaS04 alone, it was observed that certain soil
conditions preclude or make undesirable the use of CaS04 alone and combinina
amendments results in effective reclamation and a potential savSgs
costs.
78:05G-037
SED1MENT DISCHARGES IN RUNOFF FROM OKLAHOMA
CRDRAAD
Menzel, R.G., Rhoades, E.D., Olness, A.E., and Smith S J
Agricultural Research Service, Durant, Oklahoma, Water Quality Management Laboratory.
Journal of Environmental Quality, Vol. 7, No. 3, p 401-406, 1978 I fig? 4 tab?
22 ref.
220
-------
Descriptors: *0klahoma, *Fertilizers, *Nutrients, *Agricultural runoff, *Sediment
yield, *Water quality, *Soluble nutrients, Nitrates, Agricultural chemicals,
Water pollution sources, Nitrogen compounds, Nitrogen> Phosphorus, Soil properties.
Water pollution, Rainfall, Soil erosion, Sediments, Pollutants.
\
Nitrogen and phosphorus discharges in runoff from nearly level cropland and 3%
sloping rangeland were measured from July 1972 to June 1976. Sediment discharges
and runoff amounts from these 5- to 18-ha watersheds were measured from July 1966
to June 1976. Sediment and nutrient discharges varied greatly from year to year
and between different land uses. It was concluded that long records are needed to
compare discharge from different management practices. The average and maximum
annual sediment discharges, respectively, were 3,600 and 8,900 kg/ha from irrigated
cotton, 900 and 3,900 kg/ha from dryland wheat, 400 and 1,800 kg/ha from range
with limited grazing, and 9,000 and 23,000 kg/ha from overgraze range. Maximum
annual sediment discharges occurred during the period in which nutrient discharges
were measured. Maximum annual nutrient discharges were 13 kg/ha total N, 4 kg/ha
nitrate N, 11 kg/ha total P, and 2 kg/ha soluble P. The average annual discharge
for each nutrient form and land use was about half of its maximum value. Nitrate
accounted for 10 to 30% of the total N discharged. Soluble phosphate accounted
for about 20% of the total P discharged from cropland and less than 10% of that
discharged from rangeland. Annual deposition in rainfall averaged kg/ha N and 0.15
kg/ha P.
78:05G-038
IRRIGATION WATER SALT CONCENTRATION INFLUENCES ON SEDIMENT REMOVAL BY PONDS,
Robbins, C.W., and Brockway, C.E.
Agricultural Research Service, Kimberly, Idaho, Snake River Conservation Research
Center.
Soil Science Society of America Journal, Vol. 42, No. 3, p 478-481, May-June, 1978.
2 fig, 2 tab, 12 ref.
Descriptors: *Sediment control, *Irrigation, *Salts, Irrigation return flow,
Ponds, Water treatment, Coagulation, Flocculation, Runoff, Sediments, On-site
investigation, Laboratory tests, Irrigation water, Irrigation practices, Sedimen-
tation.
Irrigation water salt concentration effects on sediment pond efficiency were
investigated to demonstrate the necessity of considering the salt concentration
in the irrigation waters when designing sediment retention ponds. The influence
of dissolved salt was determined by adding concentrated CaC12 solutions to three
ponds and then measuring electrical conductivities and sediment concentrations
at the pond outlets. Increasing the salt concentration increased the sediment
removal efficiencies when the retention time in the pond exceeded 1 hour or the
inflow sediment concentration exceeded 500 ppm for the three soils studied.
Adding salt to laboratory soil sample suspensions increased the settling rates
for the two soils studied. That data indicated that the salt concentration in
irrigation water is an important factor in determining sediment pond size and
retention time. Using pond design criteria obtained from sediment ponds receiving
water of a given salt concentration to design ponds that will receive water with
a different salt concentration should include adjustments for salt concentration
differences. A simple laboratory test was suggested to predict which soils will
respond to irrigation water salt concentration changes that are likely to result
in sediment pond efficiency changes.
78:05G-039
DEVELOPMENT OF MANAGEMENT GUIDELINES TO PREVENT POLLUTION BY IRRIGATION RETURN
FLOW FROM RICE FIELDS,
Brown, K.W., Deuel, L., Price, J., DeMichele, D., and Teague, W.R.
Texas A & M University, College Station, Texas.
Publication No. EPA-600/2-78-082, April, 1978. 570 p, 147 fig, 78 tab, 170 ref,
15 append, 96 egu.
Descriptors: Water management {applied), Water quality control, Water quality,
Return flow, Water pollution control, Rice, Irrigation practices, Fertilization,
Ion transport, Computer programs.
221
-------
A three-year field and laboratory study was conducted to determine the influence
of management practices on the quantity and quality of irrigation return flow
from rice paddies. Continuous and intermittent irrigation techniques were used
on replanted field plots which received either recommended or excessive applications
of fertilizer and four selected pesticides. Water quality was evaluated with
respect to fertilizer amendments, pesticides, pH and total salt load. Pesticides
monitored included propanil molinate, carbofuran, carbaryl and their respective
metabolites. Present water management practices result in large return flow volumes.
Occasionally concentrations of NH4 exceeded drinking water standards. Losses of
nitrate were below such limits and the total nitrogen losses were a small fraction
of the fertilizer applied. A model was developed to simulate the ionic constitericy
of the return flow. Propanil was washed from the foliage into the flood water and
dissipated within 24 hours. Evidence is given that carbaryl is washed from the
leaves by rainfall, thus providing available source to contaminate return flow.
As long as 8 days were required to dissipate residue resulting from recommended
applications. Retention times to assure low concentrations in the irrigation
return flow for carbofuran are of the order of 16 days. Granular applied molinate
necessitates a retention time of 4 days to assure concentrations are within 10%
of the TLM to fish. It is suggested that through improved water management and
knowledge of dissipation rates, the quanity of irrigation return flow can be
reduced and the quality improved.
78:05G-040
TIMING AND RATE OF FERTILIZER NITROGEN FOR SUGARBEETS RELATED TO NITROGEN UPTAKE
AND POLLUTION POTENTIAL,
Hills, F.J., Broadbent, F.E., and Fried, M.
California University, Davis, Department of Soil Microbiology.
Journal of Environmental Quality, Vol. 7, No. 3, p 368-372, July-September, 1978.
4 fig, 3 tab, 11 ref.
(See 78:021-030)
78:05G-041
THE PESTICIDE CONTENT OF SURFACE WATER DRAINING FROM AGRICULTURAL FIELDS—A REVIEW,
Wauchope, R.D.
Southern Weed Science Laboratory, Science and Education Administration, Federal
Research, United States Department of Agriculture, Stoneville, Mississippi 38776.
Journal of Environmental Quality, Vol. 7, No. 4, p 459-472, October-December, 1978.
3 fig, 4 tab, 69 ref.
(See 78:10C-003)
78:05G-042
LEACHING,OF CATIONS AND CHLORIDE FROM MANURE APPLIED TO AN IRRIGATED SOIL,
Pratt, P.P.
California University, Riverside, Department of Soil Science.
Journal of Environmental Quality, Vol. 7, No. 4, p 513-516, October-December, 1978.
3 fig, 15 ref, 8 equ.
Descriptors: Leachate, Leaching, Organic wastes, Cations, Chlorides, Irrigation,
Water pollution, Water quality, Water management (applied).
Data for leached cations, (the sum of Ca(2+), Mg(2+), Na(+) and K(+)), and leached
Cl(-) and the ratio of cations to Cl(-) leached from the root zone during a 4-year
experiment with bovine manures on a Hanford soil were presented. Cation accumulation
in the soil and the cations leached were linearly correlated with cation input.
The removal of cations in harvested crops reached a maximum and then decreased as
the input of cations increased. Leached Cl(-) increased at a ratio of 1:1 with the
Cl(-) input in excess of removal in harvested crops, whereas leached cations in-
creased with increase in inputs in excess of removal in^crops and decreased with
decrease in the volume of leachate. At low leachate volumes and with dry weights
of liquid and solid manures at 21 and 40 metric tons/ha per year, respectively,
the cations leached were less than in the check plots. At high leachate volumes
manures increased the cations leached relative to the check treatment at all rates
of manure. The dominant factor in cation leaching was volume of leachate. Care-
fully controlled irrigation to attain low leachate volumes combined with manure
applications at reasonable rates could be used to reduce the overall effect of
irrigation on the leaching of salts to groundwater.
222
-------
78:05G-043
NITROGEN AND PHOSPHORUS LOSSES IN RUNOFF FROM NO-TILL SOYBEANS,
McDowell, L.L., Ryan, M.E., McGregor, K.C.,'and Greer, J.D.
Sedimentation Laboratory, Oxford, Mississippi, United States Department of
Agriculture. %
Paper No. 78-2508, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 8 p. 10 fig, 4 tab, 18 ref.
Descriptors: Water pollution, Water pollution control, Nitrogen, Phosphorus,
Soil erosion, Runoff, Nutrients, Water quality control, Soybeans, Mississippi.
No-till soybeans and corn can be grown on highly erodible loessial soils in
north Mississippi with reduced soil and plant nutrient losses. Soil loss in
1973 from no-till soybeans, planted directly through previous crop residues,
was only 0.4 metric tons per hectare (t/ha) compared with 19 t/ha from conven-
tional till. Total (solution plus sediment) nitrogen (N) and phosphorus (P)
losses from no-till soybeans were only 4.7 and 2.8 kg/ha, respectively, compared
with 46.4 and 17.6 kg/ha from conventional till. Where applicable, no-till is
a best management practice for reducing potential nonpoint pollution by sediments
and plant nutrients in surface runoff from agriculture.
78:05G-044
MINIMIZING SALT IN DRAIN WATER BY IRRIGATION MANAGEMENT—DESIGN AND INITIAL
RESULTS OF ARIZONA FIELD STUDIES,
Hoffman, G.J., Dirksen, C. , Ingvalson, R.D., Maas, E.V., and Oster, J.D.
United States Salinity Laboratory, Agricultural Research Service, United States
Department of Agriculture, 4500 Glenwood Drive, Riverside, California 92502.
Agricultural Water Management, Vol. 1, No. 3, p 233-252, November, 1978. 11 fig,
3 tab, 19 ref.
Descriptors: Water management (applied), Salinity, Drainage water, Water quality,
Leaching, Return flow, Evapotranspiration, Oranges, Alfalfa, Arizona.
Two field experiments were established in the We11ton-Mohawk Irrigation and Drainage
District of southwestern Arizona to test the feasibility of decreasing the salt
load in drainage water by reduced leaching. Results were given for the initial
2 years of the test for Valencia orange trees and the first year for alfalfa. The
water application data, substantiated by salinity sensor readings and measures
of soil chloride, indicated that the annual evapotranspiration of Valencia orange
was approximately 1375 mm on a total area basis. After 2 years, fruit yield and
quality and tree growth were not significantly different from flood-irrigated
trees that received 40% more water. It was concluded that if these results per-
sist, the salt load from citrus in the district could be reduced 40,000 Mg annually
by reduced leaching. More importantly, because of the salinity of the groundwater
pumped for water table control, the salt load exported from the district could be
reduced initially by 130,000 Mg annually. Results indicated that the alfalfa
experiment was underirrigated the first year and evapotranspiration was about
1950 mm annually. Comparisons indicated that the level basin flood irrigated
check yielded 20% more than the experiment and had about 10% leaching, an effi-
ciency that can probably not be improved.
78:050-045
RESIDUAL NITRATE-N IN FINE SAND AS INFLUENCED BY N FERTILIZER AND WATER MANAGEMENT
PRACTICES,
Smika, D.E., and Watts, D.G.
United States Department of Agriculture, Science and Education Administration,
Akron, Colorado.
Soil Science Society of America Journal, Vol. 42, No. 6, p 923-926, November-
December, 1978. 5 fig, 1 tab, 6 ref.
Descriptors: Nitrogen, Nitrates, Water management (applied), Nitrification,
Application methods, Irrigation systems, Groundwater, Water pollution, Return
flow, Corn (field).
223
-------
This study showed that on fine sandy soils fertilizer N and water management
are the key to controlling NO3(-)N movement below the root zone of an irrigated
corn crop. When the N was applied in one broadcast application at seeding, very
little N03(-)N remained in the soil at the end of the growing season, regardless
of the amount of growing season water application., Overwinter leaching of NO3(-)N
below the ISO-cm sampling depth was minimal with 13 cm of precipitation received
during these months. When N was applied through the solid set sprinkler irrigation
system during the growing season before tasseling, water application rate and
total N applied determined the amount of N03(-)N that remained in the soil at the
end of the growing season. During the overwinter period, NO3(-)N actually in-
creased in the soil due to nitrification of some of the NH4(+)-N. With proper
N application and water management, the potential for NO3(-)N leaching below
the crops' root zone can be greatly reduced.
78:056-046
RELATIONSHIPS BETWEEN AGRICULTURAL LAND AND WATER QUALITY,
Coote, D.R., MacDonald, E.M., and DeHaan, R.
Land Resource Research Institute, Central Experimental Farm, Agriculture Canada,
Ottawa, Ontario.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 79-
92. 5 tab, 11 ref.
Descriptors: Water quality, Water pollution. Land use, Agricultural watersheds,
Agricultural chemicals. Statistical methods. Great Lakes, Regression analysis.
The study described in this paper was developed as an adjunct to the Pilot
Watershed Studies of the International Reference Group on Great Lakes Pollution
from Land Use Activities (PLUARG) of the International Joint Commission (IJC)
with the objective of determining the relationships among water quality, pollu-
tant loadings and land use data gathered in watersheds representative of different
agricultural areas. The approach taken was to: (1) identify and survey a number
of purely agricultural watersheds (nonagricultural land use essentially absent)
representative of different agricultural systems in the Canadian Great Lake Basin;
(2) monitor the water quality at the watershed outlet; and (3) examine statistical
relationships between the characteristics of these watersheds and the water quality
observed at their outlets. A further objective of -the study was to provide a basis
for predictions of water quality in unmonitored agricultural areas of the Canadian
Great Lakes Basin.
78:05G-047
BEST MANAGEMENT PRACTICES FOR AGRICULTURE AND SILVICULTURE: AN INTEGRATED
OVERVIEW,
Bailey, G.W., and Waddell, T.E.
United States Environmental Protection Agency, Environmental Research Laboratory,
Athens, Georgia.
Proceedings of the 1978 Cornell Agricultural Water Management Conference, p 33-56.
5 fig, 3 tab, 17 ref.
Descriptors: Water management (applied), Management, Water pollution control,
Water pollution sources, Water quality, Legislation, Social aspects, Economic
feasibility, Institutional constraints, Forest management.
The evolution of agricultural and silvicultural practices were examined to place
the environmental effectiveness of BMPs in perspective within today's control
efforts. In addition, recent legislation was reviewed in terms of BMP identifica-
tion, selection, and implementation approaches. The technical, social, and
economic aspects of BMPs were examined by means of a systems approach. First,
the physical system characterized by natural and man-made inputs, system pro-
perties (e.g., topography and soil) and outputs/pollutant load (i.e., sediment,
pesticides, plant nutrients, heavy metals, pathogens and easily oxidizable
organics) were discussed. Second, this system was viewed as a partially con-
trollable system within the context of a larger socio-economic setting driven
by a multiplicity of exogenous forces. Socio-economic aspects of BMPs were dis-
cussed in terms of economic efficiency, social acceptability, equity, implemen-
tation incentives, and institutional arrangements. The paper identified and dis-
cussed a number of critical issues that demand attention.
224
-------
78:05G-048
CONSERVATION DISTRICT INVOLVEMENT IN 208 NONPOINT SOURCE IMPLEMENTATION,
Williams, R.E., and Lake, J.E.
National Association of Conservation Districts, Washington, D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 57-
67.
Descriptors: Water pollution control, Water quality act, Water law, Legislation,
Water management (applied). Erosion control, Sediment control, Water pollution
sources, Water quality, Soil conservation.
A brief history of the establishment of conservation districts was presented
including their authorities under the state laws enabling conservation districts
organization. In addition, fifteen states have passed additional legislation
providing districts with the authority to participate in special erosion and
sediment control programs. Examples of how these programs are working in several
of the states were discussed. The relationships of these and other programs with
the new thrust toward implementing nonpoint water quality plans using the Best
Management Practice approach was covered. Three case studies were presented where
districts have demonstrated their abilities to be management agencies for imple-
menting Best Management Practices. Finally, conservation districts' involve-
ment in carrying out 208 nonpoint implementation as a result of recent legislation
(exj Culver amendment) was provided. Administrative, technical, and funding
roles of state soil conservation agencies and conservation districts in imple-
menting BMP's were stressed.
78:050-049
THE ROLE OF CONSERVATION PRACTICES AS BEST MANAGEMENT PRACTICES,
Johnson, J.S.
Soil Conservation Service, United States Department of Agriculture, Washington,
D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 69-
78. 16 ref.
Descriptors: Water pollution control, Water pollution, Water quality control,
Water quality act. Water quality, Soil conservation. Management, Water pollution
sources. Irrigation, Water conservation.
The combination of conservation practices selected to meet the needs of a particu-
lar land and water problem and achieve the desired results was viewed as a resource
management system. Experience and research have shown that many resource manage-
ment systems are highly effective in protecting and improving water quality. The
resource management system selected may include agronomic, managerial, and struc-
tural practices that reduce nonpoint source pollution and protect water quality.
The best resource management system is one that keeps the water where it falls,
protects the resource base, and maintains water quality of the water that runs
off. it was suggested that such proved resource management systems can be used
in achieving national goals of improved water quality, and because of the recog-
nized effectiveness of conservation practices and resource management sys.tem in
controlling nonpoint source pollution, many of them can be selected and listed
as BMP in Section 208 Water quality Management plans.
78:050-050
INTEGRATING WATER QUALITY AND BEST MANAGEMENT PRACTICES,
Taverni, A.P., and Dworsky, R.P.
The New York State Assembly, Research Staff, Albany, New York.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 93-
115. 4 fig, 6 tab, 15 ref.
Descriptors: Water quality control, Water quality, Water pollution control,
Water quality act, Planning, Management, Water pollution, Hudson River, Salinity.
This paper discusses in detail the New York State Level B plans (section 209 of
Public Law 92-500) which contribute to improved water quality through the use
of common techniques. Specifically, this paper focused on the Genesee River,
Hudson River and Lake Champlain. It provided a summary of Best Management
Practices and the relation of Best Management Practices to overall water quality
management. Lastly, this paper demonstrated the viability of a state integrated
planning approach.
225
-------
78:05G-051
ENVIRONMENTAL IMPLICATIONS OF TRENDS IN AGRICULTURE AND SILVICULTURE,
Unger, S.G.
Development Planning and Research Associates, Incorporated, Manhattan, Kansas.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference,
p 117-131. 1 fig, 2 tab.
Descriptors: Environmental sanitation, Pollutant identification, Water pollution
sources, Water quality control, Agriculture, Pasture management, Range manage-
ment, Forest management, Environmental control, Pollution abatement.
In a study sponsored by the Environmental Protection Agency (EPA) the environmental
implications of production-related trends were assessed in the following five
subsectors: Agriculture—(1) Nonirrigated crop production, (2) Irrigated crop
production, (3) Livestock feedlot production, (4) Range and pasture management,
and, Silviculture—(5) Silviculture and harvest management. The period of
analysis was 1976-2010, and the emphasis was on the long-term future under
moderate growth assumptions. This presentation summarized the findings of the
EPA study including the rating and rankings—by a national evaluation workshop—
of environmentally-related trends within each of the five subsectors. Also, a
further analysis of the various types of trends within the crop production sub-
sectors was made to determine the relative importance of management practices—
compared to input-use restraints and residual-output treatments—within the crop
production system as a potential means of environmental pollution control in the
future.
78:05G-052
ESTIMATION AND MANAGEMENT OF THE CONTRIBUTION BY MANURE FROM LIVESTOCK IN THE
ONTARIO GREAT LAKES BASIN TO THE PHOSPHORUS LOADING OF THE GREAT LAKES,
Draper, D.W., Robinson, J.B., and Coote, D.R.
Guelph University, Guelph, Ontario, Canada, Department of Environmental Biology.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 159-
174. 2 fig, 4 tab, 39 ref, 3 equ.
(See 78:05A-016)
78:05G-053
THE FATE OF NITRATE IN SMALL STREAMS AND ITS MANAGEMENT IMPLICATIONS,
Robinson, J.B., Whiteley, H.R., Stammers, W.., Kaushik, N.K., and Sain, P.
Guelph University, Geulph, Ontario, Canada, Department of Environmental Biology.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 247-259.
6 fig, 2 tab, 20 ref.
(See 78:058-064)
78:05G-054
AN APPROACH TO WATER RESOURCES EVALUATION OF NONPOINT SOURCES FROM SILVICULTURAL
ACTIVITIES—A PROCEDURAL HANDBOOK,
Currier, J.B., Siverts, L.E., and Maloney, R.C.
Watershed Systems Development Group, United States Department of Agriculture—
Forest Service, Fort Collins, Colorado.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 271-280.
1 fig, 1 ref.
(See 78:05B-065)
78:05G-055
NONPOINT SOURCE POLLUTION FROM AGRICULTURE: SOME SOCIOLOGICAL CONSIDERATIONS FOR
IMPLEMENTING POLICY,
van Es, J.C., and Keasler, L.C.
Illinois University, Urbana-Champaign, Department of Agricultural Economics.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 311-319.
1 fig, 8 ref.
Descriptors: Water pollution control, Social aspects, Social participation,
Water pollution, Water quality, Water quality control, Water policy, Water
management (applied).
226
-------
Most of the discussion on NFS pollution control deals with the economics and the
technical aspects of the issue. In this paper the contributions sociological
analysis can make to the administration and' implementation of a NFS-pollution
control program were demonstrated. The first theme developed in the paper
dealt with the distinction between policy goals and the objectives of specific
programs created to reach the policy goals. The second theme dealt with the
issue of participation in programs. The paper discussed the experience in
agriculture with voluntary and mandatory programs of change and the likely conse-
quences of choosing programs with voluntary or mandatory participation strategies.
It was concluded that the program administrators will be in a better position
to administer programs if they understand the relationship of the program ob-
jectives to the policy goal and make program implementation compatible with the
various programs objectives.
78:05G-056
ANIMAL MANURE MOVEMENT IN WINTER RUNOFF FOR DIFFERENT SURFACE CONDITIONS,
Thompson, D.B., Loudon, T.L., and Gerrish, J.B.
Minnesota University, St. Paul, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management'Conference, p 145-
157. 1 fig, 4 tab, 16 ref.
(See 78:05A-018)
78:050-057
ESTIMATING PHOSPHORUS LOADING FROM LIVESTOCK WASTES: SOME WISCONSIN RESULTS,
Moore, I.e., Madison, F.W., and Schneider, R.R.
Wisconsin University, Madison, Water Resources Center.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 175-
192. 3 fig, 7 tab, 17 ref.
(See 78:05A-019)
78:050-058
ECONOMIC IMPACTS OF POLICIES TO CONTROL EROSION AND SEDIMENTATION IN ILLINOIS
AND OTHER CORN-BELT STATES,
Seitz, W.D., Osteen, C., and Nelson, M.C.
Illinois University, Urbana, Institute for Environmental Studies.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 373-
382. 10 ref.
Descriptors: Erosion control, Sediment control, Sedimentation, Soil erosion,
Economic impact, Agricultural watersheds, Linear programming, Water pollution
control, Water quality control, Corn belt.
This paper addressed 1) the costs to society of controlling agricultural nonpoint
sources of pollution, specifically erosion and sedimentation, and 2) the variation
in economic impacts as states or/and areas enact varying levels of control. A
large linear programming model of the corn-belt region which accounts for
variable corn and soybean production and prices was used in the analysis. This
model was used to evaluate alternative erosion control policies implemented in
selected areas of the corn belt. At the corn belt level, impacts on social
cost, farm income, food costs, commodity prices and production, land use, and soil
loss were discussed. The analysis of varying controls by areas was measured in
terms of impacts on the comparative advantage, farm income, crop production, land
use and soil loss of controls applied in Illinois and Wisconsin. The paper also
reported the results of an analysis of the long-run impacts of soil erosion and
soil erosion control policies on farm income. This analysis was conducted on a
representative watershed using a series of linear programming models with adjust-
ments to reflect the impacts of erosion on productivity.
78:05G-059
INSTITUTIONAL AND TECHNICAL ASPECTS OF THE DEVELOPMENT OF AGRICULTURAL BMPs IN
A GIVE-COUNTY RURAL/URBAN MICHIGAN REGION,
Jones, J.P., and Sutherland, J.C.
Williams & Works, Incorporated, Grand Rapids, Michigan.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 455-
462. 2 fig.
227
-------
Descriptors: Runoff, Soil erosion, Waste treatment, Water quality, Water
pollution, Management, Water pollution control, Water law, Michigan.
This is a case history of the development of a truly management oriented Waste
Treatment Management Plan under the provisions of Section 208 of Public Law
92-500. It emphasized the management organization at all levels—state, regional
and local—for the implementation of best management practices to control non-
point diffuse sources of water pollution. Major emphasis of the control and
management effort was directed toward urban and rural runoff and sedimentation;
agricultural pollution such as that from herbicides and pesticides; pollution
from construction practices and lesser nonpoint sources of water pollution such
as septic systems and sanitary landfills.
78:05G-060
DEVELOPMENT OF BMPs FOR AGRICULTURE—NEW YORK STATE STRATEGY,
Robillard, P.O., Walter, M.F., and Gilmour, R.
Cornell University, Ithaca, New York, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 581-
595. 7 fig, 7 tab, 6 ref.
Descriptors: Water quality control. Water pollution control, Water quality,
Water pollution, Water management (applied), Soil conservation, Farm management,
Planning, New York, Sediment control.
The identification of specific problems, knowledge of the cause-effect relation-
ships, direct installation costs and expected changes in farm income circumvent
the choice of appropriate BMP's and their potential water quality benefits. How
these concepts might be incorporated into a BMP development program for New York
State were reviewed. Associated stages of BMP development and implementation
techniques were proposed. Examples of this methodology were presented for two
case study dairy farms. Candidate management practices were judged qualitatively
and quantitatively in reducing potential soil, plant nutrient and manurial
organic matter losses from cropland. Estimated changes in farm income were cal-
culated for each measure. The risk in adopting new farm management measures and
technology were considered in this BMP selection process. The potential for
integrating soil erosion, agronomic recommendations and farm management concepts
into the water quality elements of conservation farm plans were found to be good.
Examples of this approach were presented.
78:05G-061
DEVELOPMENT OF A "208 PLAN" FOR AGRICULTURAL NONPOINT POLLUTION SOURCES IN ILLINOIS,
Vanderholm, D.H., Frank, J.F., and Taylor, A.G.
Illinois University, Urbana-Champaign, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 563-580.
Descriptors: Water pollution control, Water quality control, Water pollution,
Water quality, Planning, Pollution abatement, Water pollution sources, Soil conser-
vation, Illinois.
In June 1976", a task force on Agricultural Non-Point Sources of Pollution was
appointed to advise the Illinois Environmental Protection Agency in producing a
comprehensive water pollution control plan. Task force membership included
representatives from agriculture, state and federal agencies, universities, and
environmental groups. The task force was divided into subcommittees to deal with
the specific areas of pesticide, soil erosion, fertilizers, livestock waste and
forestry and fruit production. The problem assessment phase of the plan was com-
pleted in March of 1977 and the recommended Best Management Practices (BMPs) were
completed in October, 1977. The last phase of the report deals with recommended
implementation methods and was completed in March 1978. The objective of this
paper was to report the approach used by the task force for assessment of the
pollution problem from agricultural nonpoint sources, suggested BMPs, and imple-
mentation strategy as recommended by the task force for adoption in Illinois.
78:050-062
APPROACH FOR ANALYZING AND MANAGING AGRICULTURAL NONPOINT SOURCES IN THE STATE
OF MARYLAND,
Schoenhofer, R.F., Knight, W.A., and Hancock, C.V.
228
-------
Water Resources Administration, State of Maryland Department of Natural
Resources, Annapolis, Maryland.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 551-
561. 2 fig, 9 ref.
\
Descriptors: Water pollution control, Water quality control, Water quality, Water
quality act, Water pollution sources, Maryland, Management, Decision making,
Planning, Agricultural chemicals.
This paper covered the following topics: (1) A description of the State of
Maryland, its 208 planning areas and agencies, and a brief history of nonpoint
source control efforts before the onset of 208 planning, which was prompted by
P.L. 92-500; (2) A description of the organizational structure of the agencies
involved in 208 planning as it related to agriculture; (3) A description of the
philosophy and the benchmark decisions relating to the development of the agri-
cultural nonpoint source management program; and (4) A description of an infor-
mation management system developed by the 208 program in cooperation with the
Soil Conservation Districts, and its application as a part of program development.
78:05G-063
ESTIMATION OF AGRICULTURAL NONPOINT LOADS TO THE WAKARUSA RIVER BASIN USING THE
"NONPOINT CALCULATOR",
Davis, M.J., and Nebgen, J.W.
Midwest Research Institute, Kansas City, Missouri.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 525-
550. 1 fig, 14 tab, 2 ref, 7 equ.
Descriptors: Water pollution, Water quality, Water pollution control, Land
management, Programs, Agricultural watersheds, Sediment load, Pollutants,
Estimating, Kansas.
An analysis of the nonpoint pollution sources in the Wakarusa River basin in
eastern "Kansas was undertaken. The Wakarusa basin is primarily rural, with the
principal nonpoint pollutant loads arising from agricultural land. Soil
Conservation Service information for this basis was used to develop the "nonpoint-
calculator," a computerized methodology for estimating nonpoint loads. This
procedure was developed under the sponsorship of the U.S. Environmental Protection
Agency. The nonpoint calculator considers a variety of sources; pervious areas
(erosion-related pollutants), impervious areas (urban sources), feedlots, land-
fills, salinity from irrigation return flow, and acid mine drainage. For the
Wakarusa River basin study, the nonpoint calculator was used only for previous
agricultural land. The presentation described how the nonpoint calculator
operates, and the type of information needed for input, it was shown that
analysis of the output from the nonpoint calculator can pinpoint areas which re-
quire the development of plans for load reduction, either to preserve water
quality or to maintain the soil resource.
78:05G-064
INTERACTIVE EFFECTS OF PESTICIDE PROPERTIES AND SELECTED CONSERVATION PRACTICES
ON RUNOFF LOSSES: A SIMULATION STUDY,
Dean, J.D., and Mulkey, L.A.
Technology Development and Applications Branch, Environmental Research Laboratory,
United States Environmental Protection Agency, Athens, Georgia.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 715-
734. 7 fig, 3 tab, 28 ref.
Descriptors: Agricultural runoff, Pesticide removal. Conservation, Simulation
analysis, Agricultural chemicals. Management, Sediment discharge, Water pollu-
tion, Water pollution control, Water quality.
The prohibitive cost of long-term collection of chemical runoff data from
agricultural activities makes the use of models attractive in evaluating impacts
of management practices. This paper described a general methodology for model
implementation and cited a specific case to indicate the potential of simulation
studies for characterizing runoff losses. To test the methodology, a study was
made using two different conservation practices on opposite ends of the managerial
spectrum, three different sorptive pesticide properties, ten gradually increasing
pesticide half-lives, and three meteorological input sequences for a total of 180
229
-------
simulation years. The U.S. Environmental Protection Agency's Agricultural
Runoff Management Model (ARM) and data from the Southern Piedmont agricultural
region were used in the investigation. Results showed the interactive effects
of pesticidal properties, watershed hydrology, and conservation practices on
runoff losses of the chemicals, in water and on sediment.
78:05G-065
MODELING SOIL AND WATER CONSERVATION PRACTICES,
Beyerlein, D.C., and Donigian, A.S.
Hydrocomp, Incorporated, Palo Alto, California.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 687-
713. 9 fig, 4 tab, 16 ref, 5 equ.
Descriptors: Agricultural runoff, Water conservation, Soil conservation, Water
pollution, Model studies, Water quality, Agricultural watersheds, Sediment
discharge, Frequency analysis, Watershed management.
The U.S. Environmental Protection Agency's agricultural Runoff Management (ARM)
Model was used to study the effects of soil and water conservation practices
(SWCP) on nonpoint pollution from agricultural lands. The base conditions were
defined as conventional agricultural practices for the region. Model parameters
were then changed to represent the effects of a particular SWCP. The three
major SWCPs studied were terracing, contouring, and conservation tillage. Con-
tinuous simulations of three to ten years in length were made to quantify the
effects of each of the SWCPs compared to the base conditions. Runoff, sediment
loss, and pesticide and nutrient washoff in solution and on sediment for a SWCP
were compared with the base condition results. Results were analyzed both by
total monthly and yearly amounts and by frequency of occurrence. ARM Model
results were displayed with a Calcomp plotter to give a visual representation
of how and when runoff and pollutant amounts changed with different SWCPs. The
simulation methodology, the selection and evaluation of model parameters for
particular practices, and the evaluation of the results in terms of the effects
of different SWCPs were discussed. Limitations of the model to represent certain
agricultural practices were presented along with areas for future research.
78:05G-066
MATHEMATICAL MODELING OF WATER QUALITY EFFECTS OF AGRICULTURAL BEST MANAGEMENT
PRACTICES,
Tang, C.
URS Company, Seattle, Washington.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 625-
647. 6 fig, 5 tab, 5 ref.
Descriptors: Water quality control, Water pollution control, Water quality,
Water pollution, Mathematical models, Agricultural runoff, Biochemical oxygen
demand, Ammonia, Coliforms, Washington.
A series of computer models were used in the SNOMET/King County (Washington State)
208 study to determine the water quality effects of the implementation of best
management practices (BMPs) designed to reduce nonpoint pollutant runoff from
agricultural activities. Simulated results showed that under existing land use
conditions, the pollutant reductions for BOD, ammonia and fecal coliform loads
in the study area after BMP application were about 70%, 85% and 75%, respectively.
Under the simulation condition, a combina'tion of 7 day - 10 year low flow regime
and an annual summer storm, the results showed that the in-stream concentration
of fecal coliforms after BMP application in the Upper Snohomish River, was
greatly improved from a frequent violation to a satisfactory level with respect
to the State Standards. The results of these simulations helped to guide in the
selection of BMPs for the agricultural areas.
78:050-067
THE EVALUATION OF BEST MANAGEMENT PRACTICES FOR THE REDUCTION OF DIFFUSE POLLU-
TANTS IN AN AGRICULTURAL WATERSHED,
Cahill, T.H., Pierson, R.W., and Cohen, B.
Resource Management Associates, West Chester, Pennsylvania.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 465-
490. 14 fig, 9 tab, 10 ref.
230
-------
Descriptors: Agricultural watersheds, Land management/ Water pollution, Water
quality, Water quality control, Agricultural runoff, Eutrophication, Lake Erie,
Model studies, Great Lakes.
The Honey Creek watershed (180 s*m.) in the Sandusky basin of north central Ohio
has been the subject of research by several agencies and institutions during
1976 and 1977. The basin has served as a pilot study area for the development
of agricultural land management practices to reduce phosphorus input to Lake
Erie. A computerized land resource data base has been created to evaluate options.
Current research centers on the calibration of the EPA Nonpoint Source Model
(NFS) for the watershed, with model parameter evaluation for BMP sensitivity.
Because of the size of the basin with respect to prior NPS model calibration
studies, 14 subbasin simulations were produced using the data base. Routing
sub-routines were developed, using wave velocity for hydrographs and particle
velocity for chemographs. Recommendations were made for model parameter inputs,
to reflect greater sensitivity for management analysis.
78:05G-068
A STATE PERSPECTIVE ON NONPOINT SOURCE MANAGEMENT,
Berle, P.A.A.
New York State Department of Environmental Conservation, Albany, New York.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 17-
24.
Descriptors: Water pollution control, Water quality control, Water quality act,
Soil conservation, Water conservation, Water management (applied), State
governments, New York.
This paper projects the governmental perspective of the New York state on nonpoint
pollution control strategy. The concept of Best Management Practice (BMP) for
nonpoint source control and management was endorsed. To prevent water pollution
from rural nonpoint sources, it was felt necessary to develop BMP's tailored to
meet New York's unique physical, economic and agricultural conditions; to identify
serious nonpoint water quality problems for special priority attention; and
participation by every landowner in the^existing cooperative soil and water con-
servation program. It was concluded that since technically nonpoint pollution
control is a new and relatively unexplored area of concern, the initial BMP systems
must be carefully designed to stay within the limits of our current knowledge.
78:05G-069
BEST MANAGEMENT PRACTICES FOR SILVICULTURE,
Harper, W.C.
Weyerhaeuser Company, Tacoma, Washington.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 263-270.
Descriptors: Forest management. Forest watersheds. Water quality control, Water
pollution control, Water quality, Management, Water quality act, Pollution abatement.
The silvicultural aspects related to Section 208 planning of Public Law 92-500 was
addressed to ensure that the resulting plan is compatible with long-term forest
management objectives. It was suggested that alternative management practices are
developed for each site to allow land managers to select among an appropriate range
of acceptable management practices. It was also suggested that an assessment of the
effectiveness of Best Management Practices in meeting land management goals, in-
cluding both water quality and timber production, must be conducted following im-
plementation of the 208 plan.
78:05G-070
BEST MANAGEMENT PRACTICES FOR FERTILIZER USE,
White, W.C., and Plate, H.
The Fertilizer Institute, Washington, D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 133-141.
3 tab, 9 ref.
Descriptors: Nutrient removal. Nutrient requirements, Fertilizers, Environmental
sanitation, Water pollution, Water quality. Management, Application methods, Timing,
Water quality control.
231
-------
A few examples were presented to illustrate the wide range of factors to consider
in controlling nutrient levels in soils as to maximize plant recovery and to
minimize loss to the environment. Even with the best available matrix mathematics,
all individual factors cannot be quantitatively evaluated for every single eventual
possible field condition. The judgement of the farmer must come into play in
exercising Best Management Practices (BMP's) for nutrient use in crop production.
It was suggested that the following four BMP's for plant-nutrient use deserve
special attention: (1) matching rate of application closely to the need of each
soil-crop combination, (2) time of fertilizer application, (3) method of
application, and (4) forms of nutrients relative to crop recovery and loss to the
environment.
78:05G-071
BEST MANAGEMENT PRACTICES FOR AGRICULTURE AND SILVICULTURE,
Loehr, R.C., Haith, D.A., Walter, M.F., and Martin, C.S., Editors.
Cornell University, Ithaca, New York, College of Agriculture and Life Sciences.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, 154 fig,
159 tab, 490 ref, 57 equ.
Descriptors: Conferences, Water quality, Water pollution, Water quality control,
Water pollution control, Water quality act, Federal water pollution control act,
Water management (applied), Conservation, Wastes.
The papers presented at the 1978 Cornell Agricultural Waste Management Conference
were grouped into the following catagories and published: Governmental aspects;
Approaches for Best Management Practice (BMP) selection; Nutrient management;
Silviculture; Economic, policy and institutional aspects; State and watershed
approaches; and Modeling Studies. The emphasis for control of nonpoint pollution
sources was placed upon the use of BMP's rather than on the collection, treatment
and effluent standards approach used for control of point sources.
78:050-072
USER'S MANUAL FOR AGRICULTURAL RUNOFF MANAGEMENT (ARM) MODEL,
Donigian, A.S., and Davis, H.H.
Hydrocomp Incorporated, Palo Alto, California 94304:
Publication No. EPA-600/3-78-080, August, 1978. 163 p, 16 fig, 25 tab, 33 ref,
3 append.
Descriptors: Agricultural runoff, Model studies. Computer models, Computer
programs, Simulation analysis, Water pollution, Hydrologic budget, Sediment
load, Pesticide residues, Nutrient removal.
This user manual provides detailed instructions and guidelines for using the
Agricultural Runoff Management (ARM) Model, Versions I and II. The manual includes
a brief general description of the ARM Model structure, operation, and components,
but the primary purpose of this document is to supply information, or sources of
information, to assist potential users in using, calibrating, and applying the
ARM Model. Data requirements and sources, model input and output, and model
parameters has been described and discussed. Extensive guidelines are provided
for parameter evaluation and model calibration for runoff, sediment, pesticide,
and nutrient simulation. Sample input sequences and examples of model output
are included to clarify the tables describing model input and output. The manual
also has discussed computer requirements and methods of analysis of the continuous
information provided by the model. This manual, when used with an understanding
of the simulated processes and the model algorithms, can provide a sound basis
for using the ARM Model in the analysis of agricultural nonpoint pollution pro-
blems and management practices.
78:05G-073
POLLUTION CONTROL MANUAL FOR IRRIGATED AGRICULTURE,
Kepler, K., Carlson, D., and Pitts, W.T.
Toups Corporation, 1966 West 15th Street, Loveland, Colorado 80537.
Publication No. EPA-908/3-78-002, August, 1978. 213 p, 30 fig, 28 tab, 131 ref,
4 append.
232
-------
Descriptors: Water pollution, Water quality, Water pollution control, Agriculture,
Return flow, Salinity, Sediment, Nitrates, Pesticides, Water law, Salt balance.
The manual is intended to expand understanding of irrigated agriculture-water
quality relationships to a broad, group, including water quality interests, water
resource interests, and agricultural field technicians. Information on collecting
pertinent information on the irrigation system, sampling techniques, and evaluation
techniques for determining the water quality impacts of return flows, combined
with beneficial use aspects allow irrigation to be put into perspective with other
elements of a water quality plan. Development of best management practices (BMP's)
incorporate this water quality information plus information on the various agri-
cultural practices. Understanding of local conditions affecting BMP's can be
developed within the evaluation framework. Technical information on irrigated
agricultural practices and the pollutants associated with return flows is pre-
sented in a thoroughly-organized manner which makes it available to the layman
as well as to experienced personnel. Traditional and recently developed irriga-
tion practices are developed and evaluated in terms of use, pollutant loading
pathways, cost, and effectiveness. Pollutants are discussed in terms of occurence
in nature, loading mechanisms, evaluation techniques, and effect upon beneficial
use.
78:050-074
AN EVALUATION OF THE POTENTIAL FOR USING DRAINAGE CONTROL TO REDUCE NITRATE LOSS
FROM AGRICULTURAL FIELDS TO SURFACE WATERS,
Gilliam, J.W., Skaggs, R.W., and Weed, S.B.
North Carolina State University, Raleigh, Department of Soil Science, Agricultural
Experiment Station.
Water Resources Research Institute Report No. 128, PB 280 575, January, 1978.
108 p, 23 fig, 4 tab, 32 ref, 3 append.
Descriptors: Nitrogen, Nitrates, Denitrification, Drainage water, Drainage
effects, Oxidation-reduction potential, Agriculture, Water pollution, Return
flow, Water pollution control.
The potential of drainage control to reduce the nitrate losses to surface waters
from artificially drained agricultural fields was investigated. . This research
was an outgrowth of previous work which showed that considerable denitrification
occurred in poorly drained soils with high water tables. This resulted in less
nitrate leaving the fields in drainage waters than occurred in better drained
soils. Two locations were selected for these experiments so as to cover a range
of soil conditions representative of large areas of drained soils in the Coastal
Plains of North Carolina. Flashboard riser type water control structures were
installed in the four main tile lines or four collector ditches at each location.
Drainage was allowed to proceed normally or was prevented until water table in
the field reached any predetermined elevation. The experimental observation
showed no significant change in nitrogen concentration of the drainage water
under controlled and uncontrolled conditions. However, approximately 50%
reduction in drainage discharge was observed under controlled conditions resulting
in approximately 50% reduction in total nitrogen loss through drainage compared
to uncontrolled conditions. It was concluded that it is potentially possible to
reduce the average winter loss of nitrate-nitrogen under controlled drainage
conditions.
78:05G-075
SALINITY MANAGEMENT OPTIONS FOR THE COLORADO RIVER,
Andersen, J.C., and Kleinman, A.P.
Utah State University, Logan, Utah Water Research Laboratory.
Water Resources Planning Series Report P-78-003, June, 1978. 344 p, 53 fig, 364
tab, 249 ref, 7 append.
Descriptors: Colorado River, Colorado River Basin, Salinity, Water quality,
Water quality control, Water pollution, Economic impact, Linear programming,
Return flow, Model studies.
The study sought to provide additional information to estimate 1) economic
damages caused by various salt concentrations to agricultural and municipal
water users and 2) economic costs of salinity control measures by upstream
water users. Damages were estimated for high salinity levels to provide
233
-------
guidelines to project future conditions. Control costs were estimated with a
physical model developed to predict the response of soil, water, and crop
factors. Input-output models were used to estimate indirect economic impacts.
78:05G-076
CROPPING AN ABANDONED FEEDLOT TO PREVENT DEEP PERCOLATION OF NITRATE-NITROGEN,
Schuman, G.E., and Elliott, L.F.
United States Department of Agriculture, Agricultural Research Service, Route
1, Box 698, Cheyenne, Wyoming 82001.
Soil Science, Vol. 126, No. 4, p 237-243, October, 1978. 6 fig, 2 tab, 6 ref.
Descriptors: Nitrogen, Nitrates, Feed lots, Water pollution, Water quality,
Water quality control, Groundwater, Leachate, Crop production, Nebraska.
An abandoned feedlot was cropped to corn (Zea mays L.) and alfalfa (Medicago
sativa L.) to prevent excess buildup and deep percolation of NO3-N from the
organic and NH4-N accumulations from the feedlot operation. To eliminate part
of the N and salt accumulation, 15 cm of surface material was removed from half
the plots and replaced with field soil. Alfalfa production was 14.1 and 11.8
metric tons/ha, and corn forage production was 8.0 and 6.7 metric tons/ha,
from the intact surface and removed surface treatments, respectively. Nitrogen
uptake was two and one-half to three times greater for alfalfa than for corn,
which was reflected by the NO3-N content of the respective soil profiles.
Nitrate-N content of the corn forage exceeded 2000 ppm (above the acceptable
limit for livestock consumption), whereas the alfalfa averaged only 857 ppm,
which would allow using it as a feed without ensiling. Nitrate buildup in
the soil profiles was greater when the surface material remained in place; the
results indicated that with proper cropping, however, either method would prevent
excess NO3-N accumulation.
78:05G-077
GROUNDWATER CONTAMINATION BY FERTILIZER NITROGEN,
Duke, H.R., Smika, D.E., and Heermann, D.F.
United States Department of Agriculture, Fort Collins, Colorado 80521.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR3, p 283-291, September, 1978. 6 fig, 2 tab, 8 ref.
Descriptors: Water pollution, Water pollution control, Nitrogen, Fertilizers,
Nitrates, Denitrification, Groundwater, Water quality, Return flow, Water
management (applied), Leachate.
It was shown that excessive irrigation of the sandy soils to which center pivot
sprinklers are adaptable can result in leaching of significant amounts of nitrogen
fertilizer as N03(-). Careful water management is an effective means of controlling
N03-N losses. The USDA irrigation scheduling program was used successfully to
determine the timing and amount of irrigation necessary to maintain high crop
yields yet minimize leaching losses. Although significant NO3-N losses were
measured from fields in the study area, neither the fraction of that NO3(-) pre-
sent in return flows nor the mechanism of possible denitrification had been
identified. It was expected that if, in fact, significant denitrification occurred
in the vicinity of the water table as the data suggested, the potential for
groundwater pollution by leached nitrates is considerably reduced. Even so, care-
ful water management was considered to be an important factor in the irrigation
program as it affects efficiency of fertilizer utilization, cost of energy for
pumping, and ultimately the yield of crops produced.
234
-------
SECTION XXV
WATER RESOURCES AND PLANNING
TECHNIQUES OF PLANNING (GROUP 06A)
78:06A-001
IDENTIFICATION AND INITIAL EVALUATION OF IRRIGATION RETURN FLOW MODELS,
Walker, W.R.
Irrigation Hydrology Company, P.O. Box 1544, Fort Collins, Colorado 80522.
Publication No. EPA-600/2-78-144, July, 1978. 124 p, 3 fig, 4 tab, 160 ref, 6
append.
Descriptors: Mathematical models, Irrigation, Water resources, Water pollution,
Water, Simulation, Prediction, Water quality, Soil water, Soil chemistry.
A broad based literature review was undertaken to identify studies that had
yielded digital computer models applicable to irrigation return flow (IRF)
systems. The programs not listed in technical reports or papers were requested
from the various authors. The results of this work are 43 computer models
applicable all or in part to the analysis of IRF's and their quality. A brief
evaluation of each model is given. IRF modeling technology is well developed
theoretically but not completely verified due to the large scale of the irriga-
tion system. Most models remain in the research sphere and need to be redefined
for the wider utilization of planners. Field data are generally not available
to satisfy the input requirements of most IRF models. Accuracies of predictions
need to be determined against standardized conditions in order to further model
development and parameter sensitivities should be investigated to isolate the
most important field data.
78:06A-002
MATHEMATICAL MODELING OF PESTICIDES IN THE ENVIRONMENT,
Hill, J. IV
Environmental Research Laboratory, United States Environmental Protection Agency,
College Station Road, Athens, Georgia 30601.
In: Symposium on Environmental Transport and Transformation of Pesticides, Octo-
ber, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia, p
194-197. 24 ref.
Descriptors: Pesticides, Pesticide toxicity, Mathematical models, Environmental
effects, Ecosystems, Model studies.
This paper recommends that research needs to be directed toward mathematical
modeling that allows translation of laboratory measurements of pesticide effects
on growth, physiology, and environmental interaction to field conditions. Fur-
ther, it suggests that models need to be developed that estimate whole system
behavior based upon data representing a limited set of component interactions.
Hierarchial models with constrained subsystems and homomorphic structures derived
from influence analysis may accomplish these goals in the near future.
78:06A-003
PREDICTING AND SIMULATING PESTICIDE TRANSPORT FROM AGRICULTURAL LAND: MATHEMAT-
ICAL MODEL DEVELOPMENT AND TESTING,
Bailey, G.W. and Nicholson, H.P.
Environmental Research Laboratory, United States Environmental Protection Agency,
College Station Road, Athens, Georgia 30601.
In: Symposium on Environmental Transport and Transformation of Pesticides, Octo-
ber, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia, p 30-
37. 26 ref.
235
-------
Descriptors: Pesticides, Pesticide toxicity, Pollutants, Pollution abatement,
Environmental effects, Computer models, Mathematical models, Simulation analysis.
Small watersheds, Basins.
The transport of pesticides from agricultural lands and other compartments of the
environment has generated public apprehension concerning the fate and effects of
these compounds. Legislative mandates require guidelines to be developed cover-
ing pesticide use in order to prevent or minimize water pollution resulting from
pesticide transport from agricultural land. Computer simulation models of the
dynamic multiple rainfall-event type are being developed and refined to describe
and predict quantitatively transport of pesticides from soil as a function of
agricultural management practices, watershed characteristics, climatic factors,
and properties of soils and pesticides. This paper discusses the steps involved
in development, testing and verification of such models.
78:06A-004
TRANSIENT SUBSURFACE DRAINAGE ON SLOPING IRRIGATED LAND,
Yeh, H.J., and King, L.G.
Washington State University, Pullman, Department of Agricultural Engineering.
Paper No. 78-2037, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 21 p. 7 fig, 15 ref,
2 equ.
Descriptors: Subsurface drainage, Subsurface drains, Irrigated land, Canal
seepage, Slopes, Interception, Numerical analysis. Water table, Irrigation,
Hydrodynamics.
Parallel subsurface drains on sloping land were studied. Source of water was
upslope seepage such as from a canal as well as intermittant irrigation over the
drains. The ground surface was treated as a boundary so that both fully and
partially saturated flow conditions existed within the soil region under study.
The water table location was determined from the numerical solution of hydraulic
head as a function of space coordinates. ADI methods were used to solve the basic
partial differential equation together with appropriate initial and boundary
values. Land slopes of up to 15 degrees from the horizontal were studied. Water
table fluctuation and drain discharge were obtained over several irrigation cycles.
During recession of the water table following an irrigation, the location of the
maximum water table height between the drains moved toward the lower drain. The
water table recession following an irrigation was compared with existing theories
using only saturated flow for parallel drains on flat land. The results of this
study showed the water table height as a function of time to be greater than pre-
dicted by existing theories even for quite small slopes. The effects of partially
saturated flow and land slope on this result are discussed.
78:06A-005
INTERCEPTOR DRAINS ON SLOPING LAND,
Gharaaty-Sani, R., and King, L.G.
Washington State University, Pullman, Department of Agricultural Engineering.
Paper No. 78-2038, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 21 p. 11 fig, 2 tab,
21 ref.
Descriptors: Subsurface drains, Subsurface drainage, Interception, Canal seepage,
Seepage control, Steady flow. Numerical analysis. Seepage, Flow rates, Water
table.
A single subsurface drain intercepting seepage from an upslope source such as a
canal was studied under steady flow conditions. Numerical methods were used to
solve the nonlinear partial differential equation describing the two-dimensional
problem with both partially and fully saturated flow occurring. Three different
soils and three different depths of water in the canal were studied using this
model. The resulting water table and drain discharge were compared with pub-
lished theory based upon laboratory flume studies which neglected or minimized
partially saturated flow. The published theory predicts water table shape arid
location adequately for design purposes; however, the drain discharge given by
such theory is low (sometimes for fine textured soils, as low as fifty percent of
236
-------
that given by this study). Neglecting partially saturated flow could lead to
undersized drains on sloping lands.
78:06A-006
DRAINAGE REQUIREMENTS FOR LOWLAND RICE,
Undan, R.C., Phillips, A.L., and Hill, R.W.
Utah State University, Logan, Department of Agriculture and Irrigation
Engineering.
Paper No. 78-2041, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 21 p. 10 fig, 5 tab,
2 ref.
Descriptors: Drainage, Rice, Drainage effects, Submerged plants, Submergence,
Rainfall, Simulation analysis, Computer models, Submerged vegetation stage,
Construction costs.
Field experiments were conducted in the Philippines with the IR-30 variety to
determine the effects of depth and duration of submergence on rice yields, and
the data used with rainfall and other physical information as bases for develop-
ing guidelines for drainage system capacity selection.
78:06A-007
CENTER PIVOT IRRIGATION IN THE COLUMBIA BASIN OF WASHINGTON AND OREGON: DYNAMICS
AND IMPLICATIONS,
Muckleston, K.W., and Highsmith, R.M.
Oregon State University, Corvallis, Department of Geography.
Water Resources Bulletin, Vol. 14, No. 5, p 1121-1128, October, 1978. 1 fig, 13
ref.
Descriptors: Irrigation, Sprinkler irrigation, Columbia River, Hydroelectric
power, Institutions, Water law, Oregon, Washington, Social impact, Economic
impact.
Impacts of center pivot irrigation in the Columbia Basin were reviewed. As of
1976, over 225,000 acres were being irrigated by center pivot units in a five-
county area of the basin in Oregon and Washington. Most of the development took
place since 1970. Dynamic application of center pivot technology altered the
concept of irrigability in the study area, converting lands that were often roll-
ing, sandy, and plagued by wind erosion from low grade grazing to productive
irrigated units. This development was entirely by private enterprise, with large
corporate farms accounting for much of the effort. Little prior comprehensive
planning or coordination took place. When the circulation of water is altered on
such a massive scale, however, unplanned impacts may be far reaching. In this
case they include: 1) acceleration of the shift to high cost thermoelectric
generation, 2) alteration of state institutions designed to allocate water, and
3) possible significant alterations of the socioeconomic fabric of small rural
service centers.
78:06A-008
OPTIMAL OPERATION OF LARGE AGRICULTURAL WATERSHEDS WITH WATER QUALITY CONSTRAINTS,
Williams, J.R., and Hann, R.W., Jr.
Texas ASM University, College Station, Department of Civil Engineering.
Publication No. 96, April, 1978. 151 p, 7 fig, 16 tab, 50 ref, 127 equ.
Descriptors: Agricultural watersheds, Sediment yield, Phosphorus, Nitrogen,
Runoff, Forecasting, Model studies, Routing, Water quality, Linear programming.
Optimization.
Models were developed for predicting daily sediment, phosphorus, and nitrogen
yields from small watersheds; routing the yields through large watersheds; and
determining the optimal operating policy of the large watershed. The model for
predicting daily sediment, phosphorus, and nitrogen was developed by refining
existing models and building new ones when existing models were considered
inadequate.
237
-------
78:06A-009
NUMERICAL MODEL FOR SATURATED-UNSATURATED FLOW IN DEFORMABLE POROUS MEDIA 3.
APPLICATIONS,
Narasimhan, T.N., and Witherspoon, P.A.
California University, Berkeley, Earth Sciences Division.
Water Resources Research, Vol. 14, No. 6, p 1017-1034, December, 1978. 46 fig,
1 tab, 26 ref, 14 equ.
Descriptors: Saturated flow, Unsaturated flow, Porous media, Deformation,
Numerical analysis, Model studies, Computer models, Land subsidence, Soil water
movement, Subsurface flow.
This is the third and conclusive part of a three-paper series and describes the
application of a numerical model for saturated-unsaturated flow in deformable
porous media. In all, ten illustrative examples were presented not only to
demonstrate the validity of the method but also to highlight the fundamental
unity that exists in the basic principles of the fields of hydrogeology, soil
mechanics, and soil physics. The chosen examples involved such diverse phenomena
as soil consolidation, infiltration, and drainage and generation of fluid pres-
sures due to cyclic loading such as earthquakes.
78:06A-010
ON THE CHOICE OF THE "APPROPRIATE MODEL" FOR WATER RESOURCES PLANNING AND MANAGE-
MENT,
Rogers, P.
Harvard University, Cambridge, Massachusetts, Department of City and Regional
Planning.
Water Resources Research, Vol. 14, No. 6, p 1003-1010, December, 1978. 4 fig,
6 tab, 14 ref, 36 equ.
Descriptors: Water resources, Water resources development, Planning, Management,
Model studies, Computer models, Computer programs, Mathematical models, Opera-
tions research. Analytical techniques.
The use of symbolic models has become widespread in water resources planning and
management. The operations research literature, however, gives little guide as
to the choice of the most appropriate model for any situation. This paper out-
lined a method for comparing models of differing complexity applied to a given
situation. The hypothesis that simpler models are more appropriate than more
representative but more complex models were tested on two simple irrigation
examples.
78:06A-011
THREE-DIMENSIONAL MODELING OF GROUNDWATER FLOW SYSTEMS,
Frind, E.O., and Verge, M.J.
Waterloo University, Waterloo, Ontario, Canada N2L 3G1, Department of Earth
Sciences.
Water Resources Research, Vol. 14, No. 5, p 844-856, October, 1978. 15 fig,
3 tab, 30 refr 15 equ, 1 append.
(See 78:043-011)
78:06A-012
CLIMATE, SOIL AND VEGETATION 7. A DERIVED DISTRIBUTION OF ANNUAL WATER YIELD,
Eagleson, P.S. .
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineering.
Water Resources Research, Vol. 14, No. 5, p 765-776, October, 1978. 10 fig,
3 tab, 13 ref, 35 equ.
(See 78:02A-007)
78:06A-013
SOME PROPOSITIONS ABOUT IRRIGATION PROJECT AND SYSTEM MANAGEMENT,
Bottrall, A.F. . .
Overseas Development Institute, London, United Kingdom, Agricultural Administra-
tion Unit.
ICID Bulletin, Vol. 27, No. 2, p 68-72, July, 1978. 1 tab.
238
-------
Descriptors: Water management (applied), Irrigation, Irrigation programs.
Agriculture, Decision making. Management, Project planning, Irrigation design,
Irrigation operation and maintenance, Crop production.
This is a modified version of a gaper presented at the Overseas Development
Institute Workshop on Choices in Irrigation Management, held from 27 September-
1 October, 1976 at the University of Kent, Canterbury, (U.K.). The object
of this paper is to put forward some generalized propositions about certain
aspects of irrigation management in developing countries on which, whatever the
characteristics of a particular project or system may be, strategic decisions
will at some point have to be mdde. The propositions are concerned primarily
with projects dependent on surface water delivery systems. The propositions
advanced in this paper are derived primarily from observations made during field
research in North West India and from the desk review of case studies in other
parts of the developing world. The first set of propositions is concerned
with the broader aspects of project organization and management, the second
set with more detailed aspects of water delivery system design and operations.
But there is clearly a large degree of interdependence between propositions in
each set.
78:06A-014
ESTIMATING IMPACTS OF SILVICULTURAL MANAGEMENT PRACTICES ON FOREST ECOSYSTEMS,
Larson, P.R., Ffolliott, P.P., Rasmussen, W.O., and Carder, D.R.
Rocky Mountain Forest and Range Experiment Station, United States Department
of Agriculture—Forest Service, Flagstaff, Arizona.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference,
p 281-294. 19 ref.
Descriptors: Forest management, Forestry, Ecosystems, Computer models, Simula-
tion analysis, Land use, Planning, Water quality, Streamflow.
A family of computer simulation modules was described that would aid forest
managers and land use planners estimate the impact of management activities on
the natural resources of the forest ecosystem. This family, called ECOSIM,
includes three general modules: FLORA for estimating responses of the forest
overstory, herbaceous understory, and organic matter; FAUNA for evaluating
animal habitats, carrying capacity, and population dynamics; and WATER for
assessing streamflow yield, sedimentation, and chemical quality. A command
system enables users to operate all modules through a common language written
in straight forward user terminology. The design gives flexibility in repre-
senting management activities by operating selected modules interactively on
an appropriate data base.
78-.06A-015
SIMULATION OF STORMWATER RUNOFF AND SEDIMENT YIELD FOR ASSESSING THE IMPACT
OF SILVICULTURE PRACTICES,
Li, R.M., Eggert, K.G., and Simons, D.B.
Colorado State University, Fort Collins, Department of Civil Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference,
p. 295-307. 6 fig, 11 ref, 11 equ.
Descriptors: Watershed management. Water yield. Sediment yield, Forest
management, Model studies, Simulation analysis, Storm runoff.
During the past two decades several watershed modeling techniques have been
developed to allow the prediction of water and sediment yield. The estimation
of infiltration, runoff and sediment yield are the major process components
required for simulating watershed response. These process models, when based
on sound physical reasoning are generally recognized as an important predictive
tool in assessing the impact of land use and silviculture management schemes
on the environment. Unfortunately, these models are often necessarily complex
in formulation and require considerable expertise and computer time to achieve
reasonable results. Therefore, although quite accurate, their complexity
often seems to inhibit their utility. In order to generate an answer quickly
and with reasonable expenditure, easier techniques such as the basin recharge
method, the unit hydrograph and the Universal Soil Loss Equation are often
used despite their deficiencies. The simple watershed model presented in this
paper combines the advantages of a nonlinear, physically based approach with
the utility of an interactive format.
239
-------
78:06A-016
METHODOLOGY FOR DETERMINING THE OPTIMAL MIX OF BMPs AND AGRICULTURAL PRODUCTION
MODIFICATIONS,
Heaney, J.P., and Ammon, D.C.
Florida University, Gainesville, Department of Environmental Engineering Sciences.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p
649-664. 17 fig, 1 tab, 11 ref, 3 equ.
Descriptors: Wastes, Pollution abatement, Pollutants, Detention reservoirs,
Sediment control, Linear programming, Model studies, Sediment discharge, Dairy
industry. Water pollution.
A simple procedure for determining the optimal mix of upstream and downstream
controls in an urban area was presented by Heaney and Nix (EPA-600/2-77-083,
1977). This procedure was extended to permit evaluation of agricultural areas.
The main different between urban and agricultural problems is that the farmer
may consider production modifications in response to an imposed restriction on
pollutant discharge. A linear programming model was developed earlier by other
research workers which allows one to determine the production adjustments that
could be made on a dairy farm facing nutrient limitations. This model was
coupled with information on Best Management Practices' effectiveness presented
in another publication and was extended to evaluate waste management problems.
78:06A-017
USER'S MANUAL FOR AGRICULTURAL RUNOFF MANAGEMENT (ARM) MODEL,
Donigian, A.S., and Davis, H.H.
Hydrocomp Incorporated, Palo Alto, California 94304.
Publication No. EPA-600/3-78-080, August, 1978. 163 p, 16 fig, 25 tab, 33 ref,
3 append.
(See 78:05G-072)
240
-------
SECTION XXVI
WATER RESOURCES PLANNING
EVALUATION PROCESS (GROUP 06B)
78:068-001
AN ECONOMIC METHODOLOGY FOR EVALUATING "BEST MANAGEMENT PRACTICES" IN THE SAN
JOAQUIN VALLEY OF CALIFORNIA,
Horner, G.L., Dudek, D.J., and McKusick, R.B.
Economics, Statistics, and Cooperatives Service, United States Department of
Agriculture.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 369-393, May 15-18,
1978. 1 fig, 1 tab, 20 ref.
Descriptors: Return flow, Economic prediction, Water quality, Management,
Environmental effects.
Section 208 of Public Law 92-500 (The Federal Water Pollution Control Act
Amendments of 1972) requires the preparation of areawide waste treatment management
plans. Agricultural related pollutants such as subsurface drainage water and
irrigation tailwater containing nutrients, sediment and pesticides must be
identified and procedures and methods to control such discharges specified.
Under Section 208, the reduction of pollutants may be achieved by adopting a
set of "best management practices" that could include varying economic incentives,
establishing resource use controls and suggesting public resource investment.
To determine the economic and environmental impact of "best management practices,"
a methodology must be derived that specifies the relationship of agricultural
production practices to water and land quality and the economic cost and benefit
of changing those practices. Such a methodology is being developed to systemati-
cally collect and organize physical and economic data, specify the physical
and economic relationships and estimate the changes in agricultural production,
income, employment and resource demands from proposed "best management practices."
78:06B-002
EVALUATION OF MEASURES FOR CONTROLLING SEDIMENT AND NUTRIENT LOSSES FROM IRRIGATED
AREAS,
Fitzsimmons, D.W., Brockway, C.E., Busch, J.R., Conklin, L.R., and Long, R.B.
Idaho University, Moscow, Idaho Agricultural Experiment Station.
Publication No. EPA-600/2-78-138, July, 1978. 150 p, 51 fig, 82 tab, 59 ref.
Descriptors: Irrigation, Soil conservation, Water quality, Salinity, Economic
analysis, Management.
Field studies were conducted in two southern Idaho areas to determine the effects
of different management practices on the quality and quantity of the runoff from
surface-irrigated fields. Pollutant removal systems (primarily mini-basins,
vegetated buffer strips and sediment retention ponds) were installed at some of
the study sites and evaluated to determine their effectiveness in removing sediment
and other materials from return flows. The results indicate that water, sediment
and nutrient losses from surface-irrigated areas can be greatly reduced or elimi-
nated by the use of certain types of management practices and/or pollutant removal
systems. Linear programming models were used to determine the economic impacts of
'using different types of practices to control surface runoff and sediment losses
from model farms. The results indicate that sediment losses from surface-irrigated
fields can be reduced by as much as 50 percent at modest cost. Elimination of
surface runoff and sediment losses would require the use of sprinkler irrigation
systems and would decrease net income by about 15%. Some of the overall impacts
of pollutant losses from surface-irrigated areas were evaluated. The annual
cost of removing sediment from canals and ditches in the Boise Valley was found
to be about $20 per hectare. Irrigation return flows contribute to water quality
problems in the Boise River and downstream in the Snake River.
241
-------
78:068-003
TOPOLOGICAL CLASSIFICATIONS OF DRAINAGE NETWORKS: AN EVALUATION,
Onesti, L.J., and Miller, T.K.
Indiana University, Bloomington, Department of Geography.
Water Resources Research, Vol. 14, No. 1, p 144-148, February, 1978. 3 fig, 2 tab,
17 ref.
Descriptors: Drainage, Channels, Geomorphology, Networks, Classification, Basins,
Correlation analysis.
Channel networks for 103 drainage basins ranging in size from 0.65 to 199 sq km
were classified according to 9 topologic systems ranging from Strahler's order
and Shreve's magnitude to those recently derived by Werner and Smart. Correlation
coefficients and coefficients of determination were calculated to test the
relationship between these systems and {10} characteristics of drainage basins
and stream channels. The results suggest that (1) network properties are closely
associated with basin area and with other characteristics primarily determined by
area, (2) the hydraulic variables are essentially unrelated to all topologic
systems analyzed, and (3) certain newly proposed topologic systems* are unrelated
to all characteristics tested, including area.
78:06B-004
IMPACT OF ENERGY DEVELOPMENT ON GROUNDWATER,
The Task Committee on the Impact of Energy Development on Groundwater Resources
of the Groundwater Hydrology Committee of the Hydraulics Division,
American Society of Civil Engineers, New York, New York.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY2, p 157-168, February, 1978. 3 fig, 4 tab, 4 ref, 1 append.
Descriptors: Groundwater resources, Energy, Hydrology, Hydrologic aspects, Oil,
Gases, Coals, Oil shales, Nuclear energy.
Available information indicates that energy development in the U.S. will not soon
deplete or degrade groundwater resources over widespread areas, Very acute effects
may occur locally in the next few years, and many isolated, but serious, problems
exist now. Impacts beyond about 1990 are difficult to anticipate because of uncer-
tainties about developable energy resources, development economics and policies,
and technological advancement. However, it seems likely that predicted energy
development will cause further competition for both surface- and groundwater
resources and that the consequent greater waste outputs will add to pollution
impacts. These adverse impacts can be avoided or reduced by timely and compre-
hensive planning which also should serve to enhance potential beneficial impacts.
78:06B-005
DESCRIBING IRRIGATION EFFICIENCY AND UNIFORMITY,
On-Farm Irrigation Committee of the Irrigation and Drainage Division,
American Society of Civil Engineers.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR1, p 35-41, March, 1978. 3 fig, 11 ref, 6 equ, 1 append.
Descriptors: Irrigation efficiency, Uniformity coefficient, Standards, Irrigation,
Soil moisture, Efficiencies, Distribution.
There is an urgent need for standardization of efficiency terms used in on-farm
irrigation. The purpose of this paper is to provide meanings for several such
terms to reduce the vagueness and resulting confusion that now exists. The
committee hopes these definitions will be accepted as standards, thus reducing
conflicting usage and the consequent need for redefinition each time such terms
are used. Only terms applicable to on-farm irrigation practices are presented,
although many may be usable for larger units such as irrigation districts or basin
wide projects.
78:066-006
COMPUTER PROGRAMMING SOLID SET SYSTEMS,
Griffin, S.G.
The Toro Company, Riverside, California.
242
-------
Paper No. 79-2012, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 9 p.
(See 78:03F-058)
78:068-007
ECONOMICS OF IRRIGATION,
Sheffield, L.F.
Nebraska University, Lincoln, Department of Agricultural Economics.
Proceedings of The Irrigation Association, Stouffer's Towers, Cincinnati, Ohio,
p 76-90, February 26-28, 1978. 5 fig, 7 tab.
Descriptors: Sprinkler irrigation. Economic prediction, Economic impact, Irrigation,
Irrigated land, Cost analysis, Agriculture, Corn belt, Great Plains.
This paper reviews and discusses the accelerated growth of irrigated agriculture
with center pivot irrigation systems in the Great Plains Region in the 1970's,
and the reasons behind the severity and widespread effects of the current cost-
price squeeze on farmers and agri-business community. A detailed analysis of the
economics of irrigation leads to the conclusion that irrigated agriculture and the
irrigation industry in the United States faces a bright future despite its present
temporary problems.
78:068-008
PREDICTING YIELDS,
Haun, J.R.
Clemson University, South Carolina, Department of Horticulture.
Crops and Soils Magazine, Vol. 31, No. 2, p 7-9, November, 1978. 3 fig.
(See 78:021-035)
78:068-009
DETERMINATION OF OPTIMAL WELL CAPACITIES FOR CONTINUOUS IRRIGATION PROGRAMS,
Sanghi, A.K., Johnson, D., and Kuepper, G.
Washington University, St. Louis, Missouri, Center for the Biology of Natural
Systems.
CBNS-AE-9, NSF/RA-78-0017, January, 1978. 50 p, 11 fig, 17 tab, 18 ref, 2 append,
11 equ.
Descriptors: Water management (applied), Irrigation programs, Model studies,
Wells, Evapotranspiration, Net profit, Economic prediction, Growth stages,
Timing, Groundwater.
A method was developed to predict optimal and acceptable suboptimal well capacities
using a model developed at the University of California, Davis. Net revenue values
were calculated at various well capacities using a budget for a 132-acre field and
an equation for determining yield reduction. The well capacities were chosen based
on growth periods found to have a differential impact on corn yields. These
differential effects were discussed in terms of the optimal and suboptimal well
capacities that will fulfill water requirements through certain parts of the growth
season. This model may provide a farmer with a predictive tool so that he may
consider optimally timed water application by an optimal well capacity to maxi-
mize net revenue. In addition, it may provide information for policy makers to
enact regulations, which would make the use of groundwater resources more bene-
ficial to the society.
78:068-010
SOCIAL COSTS AND EFFECTIVENESS OF ALTERNATIVE NONPOINT POLLUTION CONTROL PRACTICES,
Alt, K.F., Miranowski, J.A., and Heady, E.O.
Economics, Statistics, and Cooperatives Service, United States Department of
Agriculture, Ames, Iowa.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 321-
327. 1 tab, 11 ref.
Descriptors: Water pollution control, Water quality control, Water pollution,
Social aspects, Cost comparisons, Cost-benefit analysis, Alternative costs,
Social impact, Environmental control.
243
-------
A study was undertaken to estimate the magnitude of the farm production cost
adjustments that would result from implementing specific environmental policies
in an intensively cropped river basin of about 940,000 acres in East-Central
Iowa. A linear programming model was used to simulate the crop growing and
erosion management activities of the area. An exponential abatement cost
function resulted for the total cost of reducing the sedimentation rate of a
reservoir at the mouth of the watershed. Some of the pollution control policies
considered in the study did not restrict the farmer's choice to that particular
crop management system which was most effective from an engineering standpoint.
It was concluded that the choice of future pollution control policies needs to
be based on the costs changes incurred by farmers as well as the administration
and surveillance costs incurred by the public agency which administers the
pollution policy, and therefore, a truly optimal choice among alternative
pollution control policies can only be made when the total of all public and
private costs is weighed against the total of all benefits received.
78:06B-011
THE ECONOMIC IMPLICATIONS OF EROSION AND SEDIMENTATION CONTROL PLANS FOR SELECTED
PENNSYLVANIA DAIRY FARMS,
White, G.B., and Partenheimer, E.J.
Cornell University, Ithaca, New York, Department of Agricultural Economics.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 341-
357. 6 tab, 8 ref.
Descriptors: Erosion control, Sediment control, Economic impact, Dairy industry,
Water law, Soil conservation, Linear programming, Pennsylvania.
Amendments to the Clean Streams Law of Pennsylvania required the state's
agricultural landowners to have erosion and sedimentation control plans imple-
mented by July 1, 1977. The purpose of this research was to investigate the
effects of implementation on the income of commercial dairy farms. The research
focused on conservation plans made by the Soil Conservation Service (SCS) for
twelve case study farms. Linear programming was used to estimate returns to
fixed resources and farm organization for three plans for each farm. These in-
cluded the base plan, before implementation of the SCS plan; the farm plan incor-
porating SCS recommendations; and a plan incorporating no-till corn production
as an alternate or supplement to other conservation practices.
78:06B-012
FARM-LEVEL ECONOMIC EVALUATION OF EROSION CONTROL AND REDUCED CHEMICAL USE IN
IOWA,
McGrann, J.M., and Meyer, J.
Iowa State University, Ames, Department of Economics.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 359-
372. 1 fig, 3 tab, 11 ref.
Descriptors: Erosion control, Fertilizers, Pesticide toxicity, Water pollution
sources, Economic impact, Model studies, Linear programming, Terracing,
Institutional constraints, Iowa.
This study concentrated on the farm-level economic impact of soil loss control
and reduced chemical use. The farms analyzed are typical of three major soil
associations in Iowa which cover a wide spectrum of farming conditions in the
state. The analysis investigated the impact of restricting soil loss from the
present to several reduced levels on net farm.income and land rents for both
specialized crop and mixed crop and livestock farms. The waste disposal pro-
blem of the limited sized livestock enterprises was not addressed in this study.
A limited analysis was made of the effect that reducing fertilizer and banning
pesticide use would have on farm income as an alternative to reduce nonpoint
pollution. Policy alternatives to control erosion, including tax rates to
achieve reduced soil loss and cost-sharing schemes for terracing, were evaluated
in farm-level models. Consideration was also made as to how information generated
in the study can be used for extensionist and farmer training.
244
-------
78:068-013
ECONOMIC IMPACTS OF POLICIES TO CONTROL EROSION AND SEDIMENTATION IN ILLINOIS
AND OTHER CORN-BELT STATES,
Seitz, W.D., Osteen, C., and Nelson, M.C.
Illinois University, Urbana, Institute for Environmental Studies.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference,
p 373-382. 10 ref.
(See 78:05G-058)
78:068-014
PROCEDURE FOR ECONOMIC EVALUATION OF BEST MANAGEMENT PRACTICES,
Dempster, T.H., and stierna, J.H.
United States Department of Agriculture, Soil Conservation Service, Washington,
D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference,
p 383-391. 1 fig, 1 tab, 3 ref.
Descriptors: Soil conservation, Soil erosion, Management, Economic impact,
Environmental effects, Water pollution, Water pollution control, Water quality,
Water quality control.
Evaluation procedures for best management practices (BMP) were discussed with
emphasis on alternative practices affecting water conservation and quality, and
production efficiency. Onsite and offsite resource problems that were identified
and measured, include those related to reduced agricultural production and in-
creased production and maintenance costs per unit of output which can result
from erosion, sedimentation, impaired water quality and reduced soil moisture.
Quantified data from the use of universalt soil loss equation, research studies
of extension, universities and Agricultural Research Services (ARS), and com-
piling of experienced crop yields were evaluated with computerized methods such
as the Crop Budget System (CBS), linear programming and value of agricultural
production. CBS is a system designed for efficient storage, rapid retrieval,
use and revision of crop budgets used to evaluate alternative systems of BMP.
Qualifying statements on nonmonetary impacts, primarily environmental issues,
were also discussed. Procedures describing the estimation of installation,
operation and maintenance costs of BMP were included, as well as methods to
assess income foregone and adverse environmental effects.
78:068-015
AN ECONOMIC ANALYSIS OF EROSION CONTROL OPTIONS IN TEXAS,
Reneau, D.R., and Taylor, C.R.
Texas ASM University, College Station) Department of Agricultural Economics.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 393-
418. 4 fig, 8 tab, 11 ref.
Descriptors: Erosion control, Soil erosion, Economic impact, Sediment control,
Water pollution, Water pollution control, Water quality, Water quality control,
Model studies, Texas.
A model for estimating the changes in farming practices, farm income, soil loss,
off-site sediment damages, and social welfare over a long planning horizon for
a watershed under various nonpoint source control options was presented. The
model was sufficiently general to permit the study of several possible nonpoint
source control options, including: (a) per acre soil loss limits; (b) soil
loss taxes; (c) conservation practice cost sharing arrangement; and (d) combi-
nations thereof. On-farm economics of conservation was imbedded in the model.
Results from this modeling approach for Lavon Reservoir Watershed were presented.
Included were the esimated changes in farming practices, farm income, soil loss,
and off-site sediment damages for the selected nonpoint source control options.
78:068-016
MODELING SOIL AND WATER CONSERVATION PRACTICES,
Beyerlein, D.C., and Donigian, A.S.
Hydrocomp, Incorporated, Palo Alto, California.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 687-
713. 9 fig, 4 tab, 16 ref, 5 equ.
(See 78:056-065)
245
-------
78:06B-017
MODELING NUTRIENT EXPORT IN RAINFALL AND SNOWMELT RUNOFF,
Haith, D.A., and Tubbs, L.J.
Cornell University, Ithaca, New York, Departments of Agricultural Engineering
and Environmental Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 665-
685. 3 fig, 11 tab, 22 ref, 19 equ.
Descriptors: Nutrient removal, Agricultural watersheds, Mathematical models,
Agricultural runoff, Model studies, Snowmelt, Water quality, Water pollution,
New York.
Several mathematical models are available for the prediction of nutrient losses
from agricultural watersheds. Most models have complex structures, require
large computer programs and data banks and must be calibrated using streamflow
data. There are obvious advantages, at least for planning purposes, in simpler
modelling approaches with modest data and computational requirements. One such
approach, which was evaluated in this paper, is the estimation of runoff from
each unit source area within a watershed, multiplication of these runoff esti-
mates by appropriate nutrient concentrations and summing the resulting mass fluxes
for all source areas in the watershed. The approach is roughly equivalent to a
distributed watershed model in which all flows are instantaneously routed to the
watershed outlet. Mass fluxes of dissolved nitrogen, dissolved phosphorus and
total phosphorus from agricultural runoff were estimated for each storm during
a period of 18 months in 1972-1974 for the Fall Creek Watershed in upstate New
York. The nutrient flux estimates were compared with measured nutrient exports
from the watershed determined from water quality samples.
78:068-018
MATHEMATICAL MODELING OF WATER QUALITY EFFECTS OF AGRICULTURAL BEST MANAGEMENT
PRACTICES,
Tang, C.
URS Company, Seattle, Washington.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 625-
647. 6 fig, 5 tab, 5 ref.
(See 78:05G-066)
78:06B-019
EVALUATION OF CONTROLS FOR AGRICULTURAL NONPOINT SOURCE POLLUTION,
Wineman, J.J., Walker, W., Kuhner, J., Smith, D.V., and Ginberg, P.
Meta Systems, Incorporated, Cambridge, Massachusetts.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 599-
624. 8 fig, 5 tab, 10 ref.
Descriptors: Water quality, Methodology, Assessments, Model studies, Alternative
planning, Water pollution, Water quality control, Evaluation.
A proposed methodology for assessing the water quality and socioeconomic impacts
of agricultural practices was described and tested in a case study based on
corn belt farming in northeastern Indiana. The potential use of the methodology
to evaluate agricultural nonpoint source pollution control policies and the
effects of alternative futures was illustrated. The development of such a
methodology for state level planning appeared feasible and to be of significant
value for broad analyses of large numbers of policy alternatives, including
identification of Best Management Practices. However, the methodology was at a
preliminary stage of development when this report was presented.
78:066-020
WATER QUALITY MODELING IN THE DELAWARE COASTAL PLAIN REGION,
Ritter, W.F., and Jensen, P.A.
Delaware University, Newark, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 507-
524. 7 fig, 3 tab, 24 ref.
Descriptors: Agricultural runoff, Model studies, Water quality, Water pollution,
Nitrogen, Simulation analysis, Storm runoff, Nitrogen cycle, Coastal Plains,
Delaware.
246
-------
A study of nonpoint modeling and the effect nonpoint sources have on water quality
was conducted for the Coastal Sussex County 208 Water Quality Program. The EPA
Agricultural Runoff Model was used in1conjunction with a one dimensional water
quality model of eleven parameters (NH-N, NO2-N, N03-N, phytoplankton-N, benthic
N, herbivore N, particular orgarfic N, dissolved organic N, ultimate BOD, dissolved
oxygen and total coliform) to analyze the effects of land use changes on water
quality. The ARM Model and water quality model were used in Indian River Bay,
Little Assawoman Bay, Rehoboth Bay and the Broadkill River. The ARM Model gave
satisfactory results for nitrogen and phosphorus nonpoint source loads. A
simulation study indicated that there would be no major water quality effects
resulting from 20 year projected increases in urban areas or other land use
changes.
METHODOLOGIES FOR VALUATION OF AGRICULTURAL CROP YIELD CHANGES—A REVIEW,
Leung, S., Reed, W., Cauchois, S., and Howitt, R. ,.f.
Eureka Laboratories, Incorporated, 401 N. 16th Street, Sacramento, California
Publication No. EPA-600/5-78-018, August, 1978. 167 p, 5 fig, 3 tab, 433 ref.
Descriptors: Crop production,•Economic impact, Economic prediction, Yield
equations, Model studies, Methodology, Reviews, Pollutants, Air pollution,
Agriculture.
This research effort was initiated with the objective to complete a review and
evaluation of the methodological and analytical techniques used to assess and
quantify the economic impact of changes in agricultural crop yields. The review
focused on two major areas: (1) physical effects of man-made and natural
factors on agricultural crop yield, and (2) methodologies and models used to
evaluate and quantify the economic impacts of crop yield changes on the farm,
the agricultural industry and finally the consumers. The major natural environ-
mental factors included in this report are climate and weather, soil and biological
conditions Air pollution was the main consideration under the man-made factors.
Three alternative models were identified for the evaluation of the cost to an
individual farm due to changes in crop yield. These models are (a) mathematical
optimization model, (b) simulation model, and (c) econometric model. Also
outlined were the regional input-output model and the regional spatial programming
model as two feasible approaches in evaluating the secondary economic impacts.
Finallv the market supply and demand theories were identified as relevant con-
cepts in analyzing the overall impacts on consumers due to crop yield changes.
78:06B-022
AN EVALUATION OF THE POTENTIAL FOR USING DRAINAGE CONTROL TO REDUCE NITRATE LOSS
FROM AGRICULTURAL FIELDS TO SURFACE WATERS,
Gillian, J.W., Skaggs, R.W., and Weed, S.B.
North Carolina State University, Raleigh, Department of Soil Science, Agricultural
wSJrResources1 Research Institute Report No. 128, PB 280 575, January, 1978.
108 p, 23 fig, 4 tab, 32 ref, 3 append.
(See 78:050-074)
247
-------
SECTION XXVII
WATER RESOURCES PLANNING
COST ALLOCATION, COST SHARING, PRICING/REPAYMENT (GROUP 06C)
78:06C-001
DRAINAGE INSTALLATION EQUIPMENTS "ECONOMICS OF THE ART",
Marsee, C.W.
Speicher Corporation, Celina, Ohio.
Paper No. 78-2527, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 9 p.
Descriptors: Drainage, Subsurface drains. Equipment, Trenches, Installation,
Costs, Return (monetary), Investment, Economics.
There are two objectives being brought out of the "Economics of the Art" on
Drainage Equipment. First, to make the drainage contractor more aware of his
cost of operation and his return on investment. Second, to illustrate the cost
of operation and return on investment between the wheel and chain trenching
machines.
78:06C-002
SOCIAL OVERHEAD CAPITAL COSTS OF IRRIGATION DEVELOPMENT IN WASHINGTON STATE,
Whittlesey, N.K., Gibbs, K.C., and Butcher, W.R.
Washington State University, Pullman, Department of Agricultural Economics.
Water Resources Bulletin, Vol. 14, No. 3, p 663-678, June, 1978. 2 fig, 4 tab,
7 ref.
Descriptors: Irrigation, Energy, Social impact. Costs, Washington, Irrigation
effects. Water resources development, Columbia river.
Increased irrigation as a means of achieving economic development can impose
significant social costs on the state or region of growth. The growth in
population induced by additional irrigation will require roads, water and sewage
facilities, schools, fire and police protection, etc. Also the increased energy
demands due to irrigation and growth in economic activity must be met. Capital
investments required to service these needs of new development can become very
large. This study attempted to measure such social overhead costs or irrigation
development for some specific irrigation project areas of Eastern Washington.
It was shown that investment costs in overhead items can reach $2,000 per acre
irrigated or $70,000 per job created. Alternatively, the annual costs can equal
$180 per acre or $6,700 per worker. These costs must be paid locally through
increased taxes, utility rates, or costs for services.
243
-------
SECTION XXVIII
WATER RESOURCES PLANNING
WATER DEMAND (GROUP 06D)
78:060-001
REMOTE SENSING OF AGRICULTURAL WATER DEMAND INFORMATION: A CALIFORNIA STUDY,
Estes, J.E., Jensen, J.R., and Tinney, L.R.
California University, Santa Barbara, Department of Geography.
Water Resources Research, Vol. 14, No. 2, p 170-176, April, 1978. 3 fig, 3 tab,
8 ref.
Descriptors: *Reraote sensing, *Water demand, "Computer models, *Groundwater
basins, *California, Agriculture, Crops, Statistics, Prediction, Simulation
analysis.
This study focuses on the use of LANDSTAT image-processing techniques to produce
cropland and crop type statistics for input into agricultural water demand pre-
diction procedures currently being employed by the Kern County Water Agency in
Kern County, California. The potential of remote sensing to provide input to
the Kern County Water Agency's groundwater basin model in a more accurate and
timely fashion is the objective of the research discussed herein. Current
accuracies associated with LANDSTAT cropland/noncropland identifications are of
the order of 98% absolute accuracy. These data are being operationally incor-
porated into model calculations on a quarterly basis. Crop specific accuracies,
although somewhat lower, are steadily being improved, and prospects for eventual
incorporation appear good. The model, which divides the San Joaquin Valley
floor portion of the Kern County groundwater basin into 251 nodal regions, is
designed to produce a total simulation of water transmission and storage through-
out the model area; it incorporates detailed, relatively' stable geologic infor-
mation in conjunction with the capabilities provided by remote sensing, the
potential exists to sample current information continually for both short-term
and long-term agricultural water demand forecasting.
78:060-002
ANALYSIS OF WATER REQUIREMENTS FOR AGRICULTURAL IRRIGATION IN PENNSYLVANIA,
Kibler, D.F., Fritton, D.D., White, E.L., Trotter, R.J., and Tandy, D.F.
Pennsylvania State University, University Park, Institute for Research on Land
and Water Resources.
Research Publication 99, September, 1977, 228 p. 28 fig, 35 tab, 6 ref.
Descriptors: *Crop production, *Climates, *Irrigation water, *Soil moisture,
*Water demand, *Water requirements, *Pennsylvania, Irrigation, Application
methods, Crops.
The objective is to identify the crops which are likely to be irrigated under
Pennsylvania's climatic conditions. The decisions are made on the basis of
the historical use of irrigation for crops as documented in census records and
on the basis of published irrigation research experiments and other carefully
documented investigations which apply. The attempt is to base decisions on
documented yield increases of a crop under irrigated conditions when compared
to yields produced by natural rainfall. The specific purpose of this investi-
gation has been to develop quantitive estimates of expected irrigation demand
by analyzing the frequency distribution of rainfall, effective precipitation
and soil moisture deficit as they vary by crop and location throughout the State.
Frequency analysis of these irrigation parameters is based upon an extensive
data base describing the hydrologic, climatologic, and agronomic conditions
found at 65 potential irrigation sites located in the primary agricultural
areas of the State. All data were analyzed by computer methods to obtain fre-
quency estimate of soil moisture deficit by crop and region. The soil moisture
deficit is a primary indicator of irrigation need which can be used to project
future irrigation demands in Pennsylvania.
249
-------
SECTION XXIX
WATER RESOURCES PLANNING
WATER LAW AND INSTITUTIONS (GROUP 06E)
78:06E-001
WESTERN WATER LAWS AND IRRIGATION RETURN FLOW,
Radosevich, G.E.
Resources Administration and Development, Incorporated, P.O. Box 1028, Fort
Collins, Colorado 80522.
Publication No. EPA-600/2-78-180, August, 1978. 257 p, 5 fig, 3 tab, 107 ref,
1 append.
Descriptors: Water law. Water rights. Irrigation, Irrigated land, Water
pollution, Water quality.
The impact of water law upon allocation and use of waters within the Western
United States is currently recognized as one of the major constraints to adapta-
tion by irrigated agriculture of more efficient operation practices. This pro-
ject provides a background of the law and evaluation of the potentials through
water law interpretations or changes to implementing improved water management
technology. Specifically, this report provides a synthesis of water laws of
each of the 17 western states, as well as providing a state-by-state account of
the water quantity laws, paying particular attention to features in the laws
and their administration that direct the manner of use and provide incentives
or disincentives to more efficient use. General recommendations are offered
that will permit or induce more efficient and effective water management.
Specific recommendations identify areas requiring additional research to reno-
vate state water laws consistent with present and prospective policies and needs.
78:06E-002
ALTERNATIVE POLICIES FOR CONTROLLING NONPOINT AGRICULTURAL SOURCES OF WATER
POLLUTION,
Seitz, W.D., Gardner, D.M., Gove, S.K., Guntermann, K.L., and Karr, J.R.
Illinois University, Urbana-Champaign, Urbana, Illinois 61801.
Publication No. EPA-600/5-78-005, April, 1978. 314 p, 22 fig, 55 tab, 168 ref,
8 append.
Descriptors: Water pollution, Soil erosion, Economics.
This study of policies for controlling water pollution from nonpoint agricultural
sources includes a survey of existing state and Federal programs, agencies, and
laws directed to the control of soil erosion. Six policies representing a variety
of approaches to this pollution problem are analyzed. The aggregate economic
impact of such policies is investigated using a state-of-the-art, market-equili-
brium, linear-programming model of crop production in the corn belt. The economic
effects of the policies at the level of individual forms and their impacts on
long-term soil productivity are analyzed through the use of a watershed model.
The institutional arrangements needed to implement the policies are examined, as
are the associated costs for a typical county. Literature on the social aspects
of policy acceptance is reviewed, and the results of a survey of the reaction of
farmers and ASCS directors in Illinois to different policies are presented. The •
equity of the policies is examined and legal precedents are reviewed.
78:06E-003
AN ANALYSIS OF PLAYA LAKE WATER UTILIZATION ON THE TEXAS HIGH PLAINS,
Templer, O.W.
Texas Tech University, Lubbock, Department of Geography.
Water Resources Bulletin, Vol. 14, No. 2, p 454-465, April, 1978. 3 fig, 34 ref.
250
-------
Descriptors: Water utilization, Playas, Texas, Semi-arid climates, Water rights,
Water law, Groundwater recharge, Runoff, Groundwater, Irrigated land.
This paper examines the spatial, temporal and legal aspects of playa lake water
utilization on the semi-arid Texas High Plains. These small basins of interior
drainage collect and briefly hold an estimated two to three million acre-feet of
runoff water annually, representing from one-fourth to one-third the quantity of
groundwater pumped from the dwindling Ogallala aquifer. Once considered a detri-
ment to farming operations, there is now increased interest in using playa water
more effectively. At present direct pumping is the chief method of utilization,
and modification of lake bottoms to concentrate runoff and reduce evaporation is
the most widespread conservation practice. The use of playa water for ground-
water recharge is hampered by as yet unsolved technical problems. For many years,
the question of ownership of playa water remained unsettled. The Texas Water
Rights Commission now classes it as diffused surface water, which under Texas law
may be used by the landowner, though some legal problems remain. For playa
lakes to be effectively integrated into the regional water resource it becomes
imperative that all present and prospective water utilization problems be
identified and resolved.
78:06E-004
208 WATER QUALITY PLANNING HOW IT WILL AFFECT YOU,
Humenik, F.J.
North Carolina State University, Raleigh, United States Department of Agriculture.
Irrigation Journal, Vol. 28, No. 3, p 6-7, 17, 24, 25, May-June, 1978.
Descriptors: Water law, Water pollution control, Water pollution, Water
pollution sources, Waste water disposal, Waste water treatment. Water quality
act, Water quality control, Water resources planning act, Planning.
208 is actually a section of Public Law 92-500, the Federal Water Pollution
Control Act Amendment of 1972. General goals of this sweeping legislation are
to restore and maintain the chemical, physical, and biological integrity of the
Nation's waters. A comprehensive discussion of "Section 208" is presented in this
article.
78:06E-005
NON-POINT POLLUTION AND THE SCS,
Agricultural Engineering, Vol. 59, No. 5, p 19-20, May, 1978.
Descriptors: Water pollution, Water pollution sources. Water pollution control,
Water quality act, Pollution abatement, Soil conservation, Legal aspects,
Agricultural engineering.
Agricultural Engineering interviews Glen H. Loomis, PE, director of the Environmen-
tal Services Division of USDA-SCS, on the Culver Amendment to the Clean Water Act.
78:06E-006
INTERNATIONAL PROBLEMS,
Holburt, M.B.
Values and Choices In the Development of The Colorado River Basin, The University
of Arizona Press, Tucson, Arizona, 1978, p 220-237. 2 fig, 1 tab, 11 ref.
Descriptors: Colorado River, Colorado River Basin, Water quality act, Water
quality, Water quality control, Water pollution control, Mexican Water Treaty,
Legislation, Salinity.
This paper discusses the Colorado River water quality and quantity problems
between the United States and Mexico, considerations that have led to the several
agreements between the two countries, and possible future actions,
78:06E-007
THE LEGALIZATION OF GROUNDWATER STORAGE,
Gleason, V.E.
Southern California Metropolitan Water District, Los Angeles.
Water Resources Bulletin, Vol. 14, No. 3, p 532-541, June, 1978. 1 fig, 16 ref.
251
-------
Descriptors: *Water law, *Water rights, *Appropriative rights, *California,
*Water storage, Legal aspects, Aquifer management, Judicial decisions, Groundwater,
Water supply.
California courts recently recognized underground aquifer storage rights that
allow public agencies to store imported waters in aquifers, to prevent others from
expropriating that water, and to recapture that water when it is needed. The two
appellate decisions representing the common-law development of aquifer storage
rights are discussed. One decision, entitled Niles Sand and Gravel Company vs.
Alameda County Water District 37 C.A. 3d 924 (1974), involved an aquifer managed
under statutory authority, while the other, City of Los Angeles vs. City of San
Fernando 14 Cal. 3d 199 (1975) , dealt with an aquifer managed under judicial
authority. These decisions offer two rationales for aquifer storage rights: (1)
to protect water supplies necessary for the overlying community, and (2) to
increase water supply efficiency by using natural underground storage whenever
possible. This paper analyzes the relationship between aquifer storage rights and
conventional groundwater rights, indicating aspects of storage rights that need
further development.
78:06E-008
A PROGRAM TO PROMOTE IRRIGATION CONSERVATION IN IDAHO,
Hammond, J.
State of Idaho, Statehouse, Boise, Department of Water Resources.
Pacific Northwest Regional Commission, March, 1978. 43 p, 6 fig, 12 ref.
(See 78:03F-107)
78:06E-009
NORTH CAROLINA 208 CASE STUDY,
Horney, L.F., Koehler, F.A., and Bliven, L.F.
North Carolina State University, Raleigh, Department of Biological and Agricultural
Engineering.
Paper No. 78-2584, Presented at the 1978 Winter Meeting of the American Society of
Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago, Illinois,
6 p. 4 ref.
Descriptors: Water pollution. Water quality, Water pollution control, Water
quality control. Planning, Water management (applied), Water law, Legislation,
Agriculture, North Carolina.
The North Carolina approach for the development of the agricultural portion of the
statewide 208 plan has been influenced by unanswered questions concerning actual
water quality and relationships between agricultural practices, conservation techni-
ques and areawide water quality. The planning organization and responsibilities,
approaches and studies undertaken leading to plan recommendations were discussed
in this paper.
78:06E-010
NONPOINT SOURCE POLLUTION CONTROL STRATEGY,
Groszyk, W.S.
Water Planning Division, United States Environmental Protection Agency, Washington,
D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 3-10.
Descriptors: Water pollution control, Water pollution. Water quality. Water
quality control. Federal water pollution control act. Water quality act, Water
law. Management.
This paper discussed the two major elements of the U.S. Environmental Protection
Agency's nonpoint source (NPS) pollution control strategy, and how two amendments
in the Clean Water Act of 1977 provide with additional ways to implement NPS
control programs, and thus solve some of the critical water quality problems. These
two major elements of EPA's nonpoint source control program were described to be:
(1) to accelerate the implementation of NPS control programs and the application
of Best Management Practices (BMP's) and, (2) to focus the available resources
on solving the most severe problems first. This paper discussed these elements
in details.
252
-------
78:06E-011
RESEARCH NEEDS AND CURRENT ACTIVITIES,
Murphy, T.A.
Office of Research and Development, United States Environmental Protection Agency,
Washington, D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 25-30.
Descriptors: Water pollution, Water quality control, Water management (applied),
Soil conservation, Water conservation, Management, Federal project policy,
Mathematical models, Environmental control.
This paper focused on broad topics regarding the renewable resources industry,
including the current concerns, issues, and emerging environmental problems. The
role of EPA in agricultural research was discussed in terms of both the nature and
extent of our activities, within the context of cooperation with the agribusiness
community. Reliance on typical soil.and water conservation measures as best manage-
ment practices for maintenance of water quality was viewed from the perspective
of present technical knowledge and system assessment capabilities. Additional
studies necessary to confirm the link between water quality and best management
practices were suggested. It was suggested that improved monitoring techniques,
instream water quality surveys, and a better understanding of sediment/pollutant
adsorption and desorption mechanisms are required in the near future to sharpen
the guidelines for establishing agricultural nonpoint source management systems.
Needed area-wide pollution problem assessment methodologies, BMP field evaluation,
mathematical modeling of transport phenomena, and predictive techniques for BMP
system comparisons were outlined. The projected extent of EPA/ORD involvement
in these future activities was examined in light of potential resource availability
and was compared with similar activities in other Federal, State, and local
agencies and institutions.
78:06E-012
CONSERVATION DISTRICT INVOLVEMENT IN 208 NONPOINT SOURCE IMPLEMENTATION,
Williams, R.E., and Lake, J.E.
National Association of Conservation Districts/ Washington, D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 57-67.
(See 78:05G-048)
78:06E-013
MANAGEMENT AND FINANCING OF AGRICULTURAL BMPs,
Rice, J.M.
URS Company, Seattle, Washington.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 329-
340. 2 fig, 1 tab, 5 ref.
Descriptors: Water quality control, Water quality, Water pollution, Planning,
Management, Agricultural runoff, Water pollution sources, Water pollution con-
trol, Programs, Washington.
One of the major goals of the Section 208 areawide waste management planning
program, mandated by PL 92-500 and administered by the U.S. Environmental Protec-
tion Agency (EPA), is to develop solutions to identified water pollution problems
which can and will be put into practice. The agricultural program developed in
SNOMET/King County (Washington) represents one approach to implementing nonpoint
water pollution control measures which both satisfies the technical and other
requirements of EPA concerning water quality management and satisfied the more
pragmatic requirements of working farmers who are concerned both about making a
living and about conservation. This paper presented the results of that program
with special emphasis on unique aspects of the social and political setting of
the SNOMET/King County area. The implemented program is in one sense no
different than those developed in many other agricultural areas of the country;
yet its acceptance by the local farming community and their willingness to
participate in implementation of the program represent an institutional achieve-
ment in itself. Process, not product, then was a major focus of this paper.
253
-------
78:06E-014
THE POLICY RELEVANCE OF ALTERNATIVE INSTITUTIONAL APPROACHES TO 208 PLANNING,
Hamilton, A., and Libby, L.W.
Michigan State University, East Lansing, Department of Agricultural Economics.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 419-
428. 4 tab, 3 ref.
Descriptors: Water quality control, Water quality act, Water pollution, Planning,
Decision making, Alternative planning, Water quality, Local governments.
The power to implement many of the best management practices to control nonpoint
pollution being considered in 208 planning lies with local governments (county,
city, town, village). But the planning for reduction of nonpoint sources of
pollution, is being done at the regional (usually multi county) of the state level,
The tradeoffs between coordination and implementation that occur at these two
different institutional boundaries were examined in this paper. It was believed
that this research will have relevance not only to the water quality planning
process but to a number of other planning exercises as well. The paper has
drawn preliminary conclusions on the policy relevance of the different planning
models discussed.
78:06E-015
ECONOMIC, INSTITUTIONAL AND WATER QUALITY CONSIDERATIONS IN THE ANALYSIS OF
SEDIMENT CONTROL ALTERNATIVES: A CASE STUDY,
Sharp, B.M.H., and Berkowitz, S.J.
Wisconsin University, Madison, Department of Agricultural Economics.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 429-
453. 6 fig, 8 tab, 20 ref, 6 equ.
Descriptors: Sediment control, Economic impact, Institutional constraints,
Water quality, Linear programming, Soil conservation, Sediment yield, Sediment
load, Model studies, Decision making.
Traditional economic analyses of the impact of conservation policies on the farm
firm have relied solely upon the establishment of soil loss constraints to
induce compliance. There are, however, different approaches to inducing a pattern
of behavior which are also consistent with achieving the desired reduction in
sediment. These policy options also have differing economic, institutional and
water quality implications. The results of a study, conducted in a 440 acre water-
shed in Washington County, Wisconsin, which explicitly recognizes a set of institu-
tional alternatives designed to modify operator behavior, were presented in this
paper. In addition, the water quality implications of these alternatives with
respect to sediment loads were illustrated.
78:06E-016
INSTITUTIONAL AND TECHNICAL ASPECTS OF THE DEVELOPMENT OF AGRICULTURAL BMPs IN
A FIVE-COUNTY RURAL/URBAN MICHIGAN REGION,
Jones, J.P., and Sutherland, J.C.
Williams & Works, Incorporated, Grand Rapids, Michigan.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 455-
462. 2 fig.
(See 78:05G-059)
78:06E-017
DEVELOPMENT OF A "208 PLAN" FOR AGRICULTURAL NONPOINT POLLUTION SOURCES IN
ILLINOIS,
Vanderholm, D.H., Frank, J.F., and Taylor, A.G.
Illinois University, Urbana-Champaign, Department of Agricultural Engineering.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 563-
580.
(See 78:056-061)
78:06E-018
APPROACH FOR ANALYZING AND MANAGING AGRICULTURAL NONPOINT SOURCES IN THE STATE
OF MARYLAND,
Schoenhofer, R.F., Knight, W.A., and Hancock, C.V.
254
-------
Water Resources Administration, State of Maryland Department of Natural Resources,
Annapolis, Maryland.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 551-
561. 2 fig, 9 ref.
(See 78:05G-062)
78:06E-019
A STATE PERSPECTIVE ON NONPOINT SOURCE MANAGEMENT,
Berle, P.A.A.
New York State Department of Environmental Conservation, Albany, New York.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 17-24.
(See 78.-05G-068)
78:06E-020
IMPROVING WATER QUALITY IN AGRICULTURE AND SILVICULTURE,
Unger, D.G.
Agriculture for Conservation, Research and Education, United States Department of
Agriculture, Washington, D.C.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 11-16.
Descriptors: Water pollution, Water quality, Water quality control, Water
pollution control, Water law, Water management (applied), Programs, Federal water
pollution control act, Federal project policy, Federal government.
This paper reports the viewpoints of U.S. Department of Agriculture on America's
water quality needs and the programs designed to meet them, it was stressed
that the overall job of upgrading water quality requires an effective combination
of good management, technical assistance, economic incentives, research and
education.
78:06E-021
POTENTIAL EFFECTS OF ENVIRONMENTAL POLICIES ON RESOURCE USE AND REGIONAL INCOMES
IN AGRICULTURE,
Vocke, G.F., and Heady, E.O.
Iowa State University of Science and Technology, Ames, Iowa.
Agriculture and Environment, Vol. 4, No. 2, p 99-109, August, 1978. 1 fig, 6 tab,
8 ref.
Descriptors: Agriculture, Crop production, Economics, Environment, Fertilizers,
Land management, Land resources, Land use.
The results of this study indicate that U.S. agriculture can comply with restric-
tive environmental policies but not without significant consequences for farmers
and their incomes. The imposition of a soil conservation policy alters crop
production patterns, changes the regional distribution of agricultural incomes,
and implies higher food expenses for consumers. A restriction on the use of
nitrogen fertilizer requires substantial substitutes of other resources to main-
tain agricultural output. However, regional production patterns are altered,
thus changing regional incomes from agriculture. A ban on the use of the organo-
chlorine insecticides Chlordane and Haptachlor causes few major changes for
agriculture but there is the potential that the incomes of some Midwest corn
farmers may be drastically reduced by an insect infestation. Requiring feedlot
operators to control the runoff from their feedlots will be particularly costly
for small livestock producers but does not significantly alter regional live-
stock production patterns. Under high exports which are not restrained by
environmental measures, land used for crops increases by 67 million acres, fert-
ilizer use increases by 29 percent, and pesticide expenditures increase by 50
percent. When the several environmental restrictions are applied simultaneously,
the value of exports must decline by 40 percent. Accompanying the reduction in
exports is a 60 percent decline in soil erosion and a 30 percent reduction in
nitrogen use.
255
-------
SECTION XXX
WATER RESOURCES PLANNING
ECOLOGICAL IMPACT OF WATER DEVELOPMENT (GROUP 06G)
78:06G-001
IRRIGATION MANAGEMENT SERVICE AND MOSQUITO CONTROL,
Hayes, R.O., and Nielsen, R.L.
Colorado State University, Fort Collins, Vector-Borne Diseases Division, Center
for Disease Control.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR2, p 153-163, June, 1978. 1 fig, 2 tab, 19 ref,
1 append.
Descriptors: Irrigation programs, Mosquitoes, Irrigation practices, Vectors
(biological), Diseases, Disease resistence, Water management (applied), Crop
production. Water pollution, Irrigated land.
The importance of irrigation to the production of agricultural crops has led to
its widespread use throughout the United States. Mosquito production and
vector-borne diseases often have been problems in intensely irrigated areas,
but in some areas good irrigation water management practices have been shown
to minimize such problems. The evaluation of the Mesa County, Colorado, Irrigation
Management Service (IMS) program found it associated with lower site and habitat
infestation rates only among the IMS orchard sites, whereas the IMS program was
not associated with reduced mosquito production among either alfalfa or corn
fields, and no mosquito production was found associated with sugar beet crops,
either in or out of the IMS program. Although pastures were not included in
the IMS program, they were included in this evaluation, and a high percentage
of the pastures examined were associated with mosquito production. The results
also revealed that the mosquito fauna, the principal types of mosquito larval
habitats, and the water sources for mosquito breeding in the irrigated areas
of Mesa County were nearly the same in 1975 as in 1959.
78:06G-002
AGRICULTURE AND CONSERVATION—ECOLOGICAL AND SOCIAL ASPECTS,
Hampicke, U.
Agriculture and Environment, Vol. 4, No. 1, p 25-42, April, 1978. 70 ref.
Descriptors: Agriculture, Conservation, Ecology, Social aspects, Political
aspects. Pesticides, Planning, Economic impact.
The technological features and the economic and political repercussions were
discussed of an agricultural system which would meet strict conservation re-
quirements in central Europe, should they exist. The rate and number of species
losses, classification of endangered species and destruction of environmental
variety were discussed. It was suggested that the countryside be divided
systematically into areas of high productivity, and others where traditional
methods of land use are continued. Three possibilities for protecting ecologically
valuable regions were discussed: abolishing the use of pesticides, etc. al-
together; improved methods of crop spraying to prevent spray falling onto adja-
cent areas; and adaptation to unavoidable spray scattering by spatial structuring,.
i.e., installing buffer areas between productive and protected zones. With re-
gard to the political and economic consequences of such a system, three indis-
pensable prerequisites were identified: an adequate system of value judgments
in society; sufficient economic flexibility to allow changes; and proper means
of coordination, i.e./ economic planning. It was concluded that gradual im-
provements on a local scale are possible and should be encouraged.
78:06G-003
ENVIRONMENTAL AND INSTITUTIONAL ASPECTS OF IRRIGATION AGRICULTURE,
van Schilfgaarde, J.
U.S. Salinity Laboratory, Riverside, California.
256
-------
Paper No. 78-2045, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 6 p. 7 ref.
Descriptors: Irrigation, Salinj>ty, Drainage, Institutional constraints, Environ-
mental effects, Social aspects, Irrigated land. Irrigation design, Water
management (applied), Agriculture.
Irrigation agriculture requires drainage, but design options and water management
choices impact not only agricultural production. A host of institutional and
societal considerations affect the viability of technically feasible alternatives.
Drainage, as an integral part of water management, must be viewed within this
larger framework and options identified that optimize total resource use.
257
-------
SECTION XXXI
RESOURCES DATA
NETWORK DESIGN (GROUP OTA)
78:07A-001
LEARNING TO IRRIGATE. . .WITH 5000 TENSIOMETERS,
Henry, C.
Irrigation Age, Northwest/Pacific Editor.
Irrigation Age, Vol. 13, No. 3, p 6-8, November-December, 1978. 4 fig.
Descriptors: Tensiometers, Scheduling, Irrigation, Idaho.
This article reports the experience of an irrigation consultant with the use
of tensiometers for irrigation scheduling.
78:07A-002
PREDICTING IRRIGATION RETURN FLOW RATES,
Bondurant, J.A., Brockway, C.E., and Brown, M.J.
United States Department of Agriculture-Science and Education Administration,
Brawley, California.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 21SW, No. 6, p 1142-1143, December 20, 1978. 2 fig, 2 tab, 4 ref, 1 equ.
Descriptors: Return flow, Sediment load, Sediment distribution, Streamflow,
Design flow, Irrigation.
Return flows from irrigated areas in southern Idaho were analyzed and a
relationship was developed that characterizes flows by relating the cummulative
percent of total seasonal flow to maximum flow rate. Since maximum flow rate
can be estimated from channel characteristics and flow evidence, it was suggested
that design flow rates' sediment ponds can be selected where flow records are
not available.
78:07A-003
SPATIAL VARIABILITY OF SOLUBLE SALT CONTENT IN A MANGOS SHALE WATERSHED,
Wagenet, R.J., and Jurinak, J.J.
Utah State University, Logan, Department of Soil Science and Biometeorology.
Soil Science, Vol. 126, No. 6, p 342-349, December, 1978. 4 fig, 2 tab, 11 ref,
4 equ.
Descriptors: Salinity, Saline water, Saline soils, Spatial distribution, Colorado
River Basin, Water quality, Sampling, Statistical methods, Soil chemical properties.
A study was conducted to examine data collected in the microwatershed land process
studies with regard to quantifying spatially variable soil properties. All 35
sampling sites were classified as occurring on the Mancos shale formation within
a 777 sq km (300 sq mi) area of the Price River Basin. Samples were taken at 0-2.5,
2.5-7.5, and 7.5-15.0-cm depths. Using the electrical conductivity (EC) of either
the 1:1 or saturation extract as the salinity index parameter, it was found that
EC values were distributed log-normally about the mean EC value of 35 observations.
The coefficient of determination for the log-normal statistical plots was 1.00 for
all three depths sampled at the 35 sites. The variance in the EC values increased.
with depth.
258
-------
SECTION XXXII
RESOURCES DATA
DATA ACQUISITION (GROUP 07B)
78:078-001
ASSEMBLY FOR MOUNTING HYDRAULIC SOIL CORE SAMPLER ON TRACTOR FRONT,
Ginn, L.H., Heatherly, L.G., and Russell, W.J.
United States Department of Agriculture, Agricultural Research Service,
stoneville, Mississippi.
Soil Science Society of America Journal, Vol. 42, No. 3, p 512-514, May-June
1978. 4 fig, 6 ref.
Descriptors: Cores, Sampling, Soil types, Hydraulic equipment.
A front-mounted tractor assembly for support of a hydraulic soil core sampler
was constructed. The design satisfies requirements for rapid soil or root
core sampling. An essential part of the assembly is a tool bar which allows
lateral movement of the mounted core sampler. The assembly with mounted
sampler is capable of extracting 1.9 to 10.2-cm diameter cores to depths as
great as 125 cm throughout a 102-cm lateral path.
78:078-002
IMPROVED TECHNIQUES FOR MARKING AND SAMPLING BAND-APPLIED FERTILIZERS AND
PESTICIDES,
Hendrickson, L.L., Keeney, D.R., Lesczynski, D.B., and Walsh, L.M.
Wisconsin University, Madison, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 3, p 507-508, May-June
1978. 1 fig, 1 tab, 10 ref.
Descriptors: Nitrification, Inhibitors, Sampling, Marking, Techniques, Nitrogen
compounds.
Techniques for marking and sampling banded fertilizers were developed to estimate
the rate of nitrification and the recovery of N from the band treated with a
nitrification inhibitor. The band was marked by applying prilled elemental S at
the point of fertilizer application. The sampler was constructed of stainless
steel and was 15 by 15 by 40 cm long. It was inserted into the soil above the
previously located band and then removed and disassembled, and the soil subsec-
tioned for a vertical profile of constituents in the band. The expanded dimen-
sions of the sampler reduced sample variability, yet still allowed sufficient
sampling efficiency to obtain adequate replication. These techniques provided
more accurate estimates of nitrification and recovery of applied N and should
find application in monitoring other fertilizers or pesticides on easily pene-
trated soils devoid of rocks.
78:078-003
COLORIMETRIC DETERMINATION OF UREA IN SOIL EXTRACTS USING AN AUTOMATED SYSTEM,
Douglas, L.A,, Sochtig, H., and Flaig, W.
Melbourne University, Australia, School of Agriculture and Forestry.
Soil Science Society of America Journal, Vol. 42, No. 2, p 291-292, March-April,
1978. 1 fig, 1 tab, 2 ref.
Descriptors: Ureas, Coloriraetry, Analytical techniques. Inhibitors, Soil tests,
Automation.
A method is described for using an automated system to determine urea in 2M KCl
soil extracts that contain a urease inhibitor (phenylmercuric acetate). The
method is sensitive and precise and allows 90-120 extracts to be analyzed per day.
259
-------
78:078-004
A NEW APPROACH TO SOIL TESTING: III. DIFFERENTIAL ADSORPTION OF POTASSIUM,
Stout, W.L., and Baker, D.E.
Pennsylvania State University, University Park, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 2, p 307-310, March-April,
1978. 1 fig, 7 tab, 17 ref, 10 equ.
Descriptors: Soil tests. Potassium, Cation adsorption, Nutrient requirements,
Cation exchange, Soil chemical properties. Regression analysis.
Donnan type ratios were used to develop an index to account for the differential
adsorption of K in two widely different soils of the Rayne and Hublersburg series.
This index was used to calculate an adjusted K requirement for the soils using
the approach of Baker. Three corn hybrids (Zea mays L.) were grown in the two
soils treated with different levels of K and multiple regression analysis was
used to relate soil test variables to plant K content. Most of the variation
in the index, K sub E/S, was associated with soil effects, making the index
useful in characterizing the two soils with respect to differential K adsorption
and in calculating soil K requirements. Over 60% of the variation in plant K
content was explained by the soil K requirement calculated from the index.
Compared with a critical K level of 98 ppm exchangeable K for soils with a CEC
of 10 mez/100 g and a K sub E/S of 1.0, the comparable critical values for K
were 71 ppm for the Rayne and 114 ppm for the Hublersburg.
78:07B-005
QUANTITATIVE ESTIMATION OF LIVING WHEAT-ROOT LENGTHS IN SOIL CORES,
Ward, K.J., Klepper, B., Rickman, R.W., and Allmaras, R.R.
Columbia Plateau Conservation Research Center, Pendleton, Oregon, United States
Department of Agriculture.
Agronomy Journal, Vol. 70, No. 4, p 675-677, July-August, 1978. 4 tab, 5 ref.
Descriptors: Root development, Wheat, Dicots, Monocots, Sampling, Cores.
A rapid, efficient method for separating living wheat (Triticum aestivum L.) roots
from dead roots in field soil samples has been proposed. Combined techniques of
separation, staining and length measurements were used to determine root density
with an accuracy of ^9%. It was observed that most monocot roots stained more
intensely than dicot roots, indicating that monocot-dicot root separation from
the same root medium may facilitate studies of root competition.
78:078-006
MEASURING SYMBIOTIC NITROGEN FIXATION IN RANGELAND PLOTS OF TRIFOLIUM
SUBTERRANEUM L. AND BROMUS MOLLIS L.,
Phillips, D.A., and Bennett, J.P.
California University, Davis, Department of Agronomy and Range Science and
Vegetable Crops.
Agronomy Journal, Vol. 70, No. 4, p 671-674, July-August, 1978. 3 fig, 1 tab,
16 ref.
Descriptors: Nitrogen fixation, Range grasses, Legumes, Clovers, Range management,
Symbiosis, Isotop studies.
The 15N A-value technique and the acetylene reduction method were compared for
their accuracy in determining seasonal symbiotic N2 fixation on a ground area basis
in rangeland plots of Trifolium subterraneum L. and Bromus moHis L. To simulate
range management practices, seeds-were planted at 10, 141, or 1970 seeds/sq m in
pure stands of 50:50 mixtures in Laughlin loam, a member of the fine-loamy, mixed,
raesic family of Ultic Haploxerolls. Amounts of N2 fixed, calculated by the 15N
A-value technique, varied significantly with planting density and proportion of
clover at different densities. Seasonal, symbiotic N2 fixation, calculated from
the acetylene reduction method, did not vary significantly with either planting
density or proportion of clover. It is concluded that with appropriate studies
on possible differences in isotope accumulation by a grass and a legume, including
morphological, physiological, and bio-chemical differences, the 15N A-value
technique should be more quantitative and discriminatory than the acetylene
reduction technique. The single seasonal sampling requirement of the 15N A-value
technique also is more amenable to the overall goal of determining the effect of
range management systems on symbiotic N2 fixation.
260
-------
78:078-007
RELATIONSHIP BETWEEN LEAF AREA AND DRY MATTER IN WINTER WHEAT,
Aase, J.K.
Northern Plains Soil and Water Research Center, P.O. Box 1109, Sidney,
Montana 59270. 4
Agronomy Journal, Vol. 70, No. 4, p 563-565, July-August, 1978. 3 fig, 14 ref.
Descriptors: Wheat, Leaves, Plant growth, Growth stages, Montana.
Models of plant growth and plant water use often require leaf-area measurements,
a potentially time-consuming and costly process. The objective of this study
was to determine if by establishing a relationship between leaf area and dry
matter in winter wheat (Triticum aestivum L. em Thell), that dry matter can be
substituted for leaf area. Four cultivars of winter wheat were seeded on Dooley
sandy loam .and Williams loam (fine-loamy, mixed, Typic Argiborolls) in northeastern
Montana in three divergent growing seasons. Leaf area and dry matter determina-
tions, from random 30-cm row plant samples cut at ground level, were made weekly
throughout the season. Leaf area and leaf dry matter were closely correlated
(coefficient of determination = 0.951). Leaf area vs. plant dry matter also was
closely correlated (coefficient of determination = 0.948) through the fifth
growth stage (leaf sheaths strongly erect, tillering complete). Thus it appears
that in studies and modeling efforts where leaf area indices are needed, at least
for winter wheat, leaf dry matter may be substituted for leaf area index.
78:07B-008
THE AUTOMATIC DETERMINATION OF ppb LEVELS OF AMMONIA, NITRATE PLUS NITRITE, AND
PHOSPHATE IN WATER IN THE PRESENCE OF ADDED MERCURY (II) CHLORIDE,
Skjemstad, J.O., and Reeve, R.
Commonwealth Scientific and Industrial Research Organization, St. Lucia,
Queensland 4067, Australia, Division of Soils.
Journal of Environmental Quality, Vol. 7, No. 1, p 137-141, January-March, 1978.
4 fig, 3 tab, 17 ref.
Descriptors: Ammonia, Nitrates, Nitrites, Phosphates, Preservation, Chemical
analysis.
Three automated procedures are reported for the simultaneous determination of
ammonia, nitrate plus nitrite, and phosphate in water. The ammonia determina-
tion is based on the salicylate-dichloroisocyanurate reaction in the presence
of nitroprusside preceded by in-line distillation. Nitrate plus nitrite is
estimated by using an in-line copperized cadmium reductor, diazotizing the ni-
trite with sulphanilamide, and coupling with N-1-naphthylethylenediamine.
Phosphate is estimated by reaction with molybdate and reduction to molybdenum
blue with ferrous ammonium sulphate. Mercury (II) chloride used as a preserva-
tive does not interfere with the methods and good precision at ppb levels can
be obtained.
78:07B-009
A NEUTRON ACTIVATION METHOD FOR DETERMINING SUBMICROGRAM SELENIUM IN FORAGE
GRASSES,
Cook, K.A., and Graham, E.R.
Missouri University, Columbia, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 1, p 57-60, January-
February, 1978. 1 fig, 5 tab, 7 ref.
Descriptors: Fescues, Forage grasses, Neutron activation analysis, Radiochemical
analysis, Irradiation.
Neutron activation as a method for the analysis of submicrogram amounts of Se
in fescue and orchard leaves was evaluated. It was observed that the Se content
of National Bureau of Standards orchard leaves was 0.078 ppm compared with the
NBS reported value of 0.080 ppm Se. The relative standard deviation for the
orchard leaves was found to be 5.3%. Following irradiation and nitric-perchloric
acid digestion, Se was extracted from a 4M HBr solution using benzene containing
1% phenol. The method is sufficiently sensitive to measure with accuracy 0.010
ppm Se in 0.250 g of material. The method is straightforward and accurate and
requires the extraction of Se in benzene which is completely free of phosphorus.
261
-------
78:078-010
SODIUM BICARBONATE EXTRACTION TO ESTIMATE NITROGEN, PHOSPHORUS, AND POTASSIUM
AVAILABILITY IN SOILS,
Bar-Yosef, B,, and Akiri, B.
Division of Soil Chemistry and Plant Nutrition, Bet Dagan, Israel, The
Volcani Center.
Soil Science Society of America Journal, Vol. 42, No. 2, p 319-323, March-April,
1978. 6 fig, 3 tab, 8 ref, 2 equ.
Descriptors: Soil analysis, Soil chemical properties, Soil tests. Nitrogen,
Phosphorus, Potassium, Calcareous soils. Sodium compounds, Nutrients.
The extractability of N03-N, P, and K from five calcareous soils differing in
physical and chemical characteristics by NaHCO3 (0.5M, pH 8.5) was studied under
laboratory conditions. The extracted amounts of the three ions were related to
time since their application to the soils, to the equilibration period of the
soils with the extractants, to the concentration of the ions in the soils, and
to the clay content of the soils. After about 70 days in the soil, the extract-
ability of each ion at a given application level was independent of time. The
recovery percentage of P and K as a function of the applied amounts of these
elements depended mainly on the clay content of the soils, while NO3-N recovery
was independent of the factors studied. Linear relationships were obtained
between NaHC03- and NH4OAC-extracted K, and NaHC03- and KCl-extracted NO3-N.
The slopes for N03-N were 45 degrees for all soils, but were specific for each
soil in the case of K.
78:073-011
NEW FLUME BREAKTHROUGH FOR DITCH IRRIGATORS,
Clemmens, A.J., and Replogle, J.A.
United States Water Conservation Laboratory, Science and Education Administration,
Phoenix, Arizona.
Irrigation Age, Vol. 12, No. 7, p 82-88, April, 1978. 3 fig, 3 tab.
Descriptors: Flumes, Equipment, Open channel flow. Flow measurement, Cost
analysis. Cost comparisons, Critical flow. Ditches, Irrigation, Arizona.
New design methods for critical-flow flumes installed in open channels make on-
farm flow measurement simple, accurate, and inexpensive. This paper describes
the methods and construction procedures used in developing a new flume to
measure water flow in open channels. The cost analysis of the eight flumes
tested shows that the cost of the flume is very inexpensive compared with other
types of flumes. It also claims to be precise within j^2%.
78:07B-012
DEVELOPMENT OF A DTPA SOIL TEST FOR ZINC, IRON, MANGANESE, AND COPPER,
Lindsay, W.L., and Norvell, W.A.
Colorado State University, Fort Collins, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 3, p 421-428, May-June,
1978. 4 fig, 7 tab, 31 ref.
Descriptors: Chelation, Soil tests, Spectrophometry, Nutrients, Fertilizers,
Sweet corn, Sorghum, Colorado.
A DTPA soil test was developed to identify near-neutral and calcareous soils
with insufficient available Zn, Fe, Mn, or Cu for maximum yields of crops.
The extractant consists of 0.005M DTPA, O.lM triethanolamine, and O.OlM CaC12,
with a pH of 7.3. The soil test successfully separated 77 Colorado soils on
the basis of crop response to Zn, Fe, and Mn fertilizers. Development of the
soil test was based, in part, on theoretical considerations. The extractant
is buffered at pH 7.30 and contains CaC12 so that equilibrium with CaCO3 is
established at a CO2 level about 10 times that of the atmosphere. Thus, the
extractant precludes dissolution of CaC03 and the release of occluded nutrients
which are normally not available to plants. DTPA was selected as the chelating
agent because it can effectively extract all four micronutrient metals. Factors
such as pH, concentration of chelating agent, time of shaking, and temperature
of extraction affect the amount of micronutrients extracted and were adjusted
for maximum overall effectiveness.
262
-------
78:078-013
A RAPID METHOD FOR ESTIMATING THE NITROGEN-SUPPLYING CAPABILITY OF A SOIL,
Fox, R.H., and Piekielek, W.P.
Pennsylvania State University, University Park, Department of Agronomy.
Soil Science Society of America*Journal, Vol. 42, No. 5, p 751-753, September-
October, 1978. 2 fig, 1 tab, 8 ref.
Descriptors: Nitrogen, Nutrient requirements, Fertilization, Nutrients, Crop
response, Corn (field), Correlation analysis, Estimating, Data collections.
Nitrogen fertilizer recommendations in humid regions have been primarily based
on crop N requirements without regard for the variability in the N-supplying
capability of the soil. The authors found (reported in a separate article) that
two previously proposed N availability indexes, 0.01M KaHC03 and boiling 0.01.M
CaC12 extractable N, were well correlated (r=0.77 and 0.86, respectively; P <
0.01 for both) with the capability of eight Pennsylvania soils to supply N to
field grown corn, (Zea mays L.) However, the time and expense required for
these analyses may preclude their routine use by soil testing laboratories. In
seeking ways to shorten and simplify the analyses, it was found that the ultra-
violet (UV) absorption by the 0.01M NaHC03 soil extract at 260 nm was as well
correlated with the N-supplying capability of the test soils (r=0.865 P < 0.01)
as the best of the previously evaluated extractable N indexes. This new method
is as rapid, simple, and inexpensive as the methods currently used to measure
availability of other essential nutrients in the soil. It was also demonstrated
how this method can be used to predict more accurately the fertilizer N needs
for corn.
78:07B-014
GREENHOUSE EVALUATION OF RESIDUAL PHOSPHATE BY FOUR PHOSPHORUS METHODS IN
NEUTRAL AND CALCAREOUS SOILS,
Bowman, R.A., Olsen/ S.R., and Watanabe, F.S.
Colorado State University, Fort Collins, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 3,- p 451-454, May-June,
1978. 3 fig, 3 tab, 32 ref, 2 equ.
Descriptors: Phosphorus, Chemical analysis, Soil chemical properties. Calcareous
soils, Carriers, Greenhouses.
Four determinations of phosphorus—Olsen P, Colwell-P, total exchangeable P, and
reain-extractable P—were evaluated in terms of total plant P uptake in a 3-year
continuous greenhouse study of 23 high P calcareous and neutral soils. All
methods were highly correlated with the total P taken up from the soils by 5-8
successive greenhouse crops. The Olsen-P procedure extracted an average of
nearly 50% of the total plant P while the colwell procedure extracted nearly
80%. Rasin-extractable P and total exchangeable P values approximated the total
plant P uptake, and served as good biological measures of the total plant-
available P in the soil. No significant differences were observed between the
carrier and carrier-free 32P methods on the 23 tests soils.
73:G7B-Q15
AN INEXPENSIVE PRECIPITATION GAUGE,
Buchanan, B.A., DeVelice, R.L. and Urquhart, N.S.
New Mexico State University, University Park, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 3, p 532-533, May-June,
1978. 2 fig, 2 ref.
Descriptors: *Rain gages, *Design, *Equipment, Precipitation (atmospheric),
Rainfall, Measurement, Instrumentation, Gages, Arid lands, Meteorology.
An inexpensive, yet accurate, precipitation gauge was developed from readily
available materials. The gauge accurately estimated precipitation as measured
by a standard Weather Bureau gauge for 35 precipitation events in a one-year
period. This inexpensive gauge has been used successfully in the field for two
years.
263
-------
78:078-016
PESTICIDE TRANSPORT AND METABOLISM IN MODEL SYSTEMS,
Kaufman, D.D., Kearney, P.C., and Nash, R.G.
Pesticide Degradation Laboratory, Beltsville, Maryland 20705.
In: Symposium on Environmental Transport and Transformation of Pesticides,
October, 1976, Tbilis, USSR. EPA-600/9-78-003, February, 1978, Athens, Georgia,
p 61-72. 6 fig, 2 tab, 14 ref.
Descriptors: Pesticides, Pesticide kinetics, Pesticide residues, Metabolism,
Assay, Soil microbiology, Microbial degradation, Sorption, Ecosystems, Laboratory
tests.
Laboratory studies devoted to investigating the environmental fate of pesticides
have usually examined individual processes such as microbial metabolism, soil
leaching, surface and vapor phase photodecomposition, volatilization from plant
or soil surfaces, and plant uptake. In the environment, however, all of these
processes may be operative on the molecule, so that in each stage of the pesticide
dissipation process, one or more processes may play a major role. It has been
extremely difficult to study two or more of these processes under controlled
conditions which will enable a clear understanding of the contribution of each.
Simplified model laboratory systems are now being developed which enable simul-
taneous measurement of numerous factors affecting pesticide dissipation in the
environment. This paper is a discussion of a few model laboratory systems.
78:076-017
RAPID DETERMINATION OF SOIL WATER CHARACTERISTIC BY THERMOCOUPLE PSYCHROMETRY,
Riggle, F.R., and Slack, D.C.
Minnesota University, St. Paul, Department of Agricultural Engineering.
Paper No. 78-2026, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 24 p. 6 fig, 1 tab,
34 ref, 4 equ.
Descriptors: Soil water, Moisture content, Moisture tension, Soil moisture,
Soil properties. Moisture availability, Soil tests, Drying, Irrigation, Osmotic
pressure.
A procedure was developed for determination of the soil water characteristic
curve with thermocouple psychrometry. Complete soil water characteristic curves
were obtained for a Nicollet clay loam, a Waukegan silt loam, and a Hubbard
sandy loam within one week in ambient air conditions. The curves obtained by
the psychrometer method compared favorably with those obtained by pressure
methods.
78:07B-018
THE SPECTROPHOTOMETRIC AND FLUOROMETRIC DETERMINATION OF ALUMINUM WITH 8-
HYDROXYGUINOLINE AND BUTYL ACETATE EXTRACTION,
Bloom P.R., Weaver, R.M., and McBride, M.B.
Minnesota University, St. Paul, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 713-716, September-
October, 1978. 2 .fig, 3 tab, 11 ref.
Descriptors: Aluminum, Chemical analysis, Analysis, Spectrophotometry, Fluorometryi
Acidic soils, Solvent extractions, Organic matter.
A spectrophotometric method and a fluorometric method for the determination of Al
by the extraction of the Al-hydroxyquinolate complex with butyl acetate were
evaluated. The Al complex was found to be very stable in butyl acetate. The
spectrophotometric method was found to be useful for the analysis of solutions
containing 50 ppb Al or greater. The spectrophatometric response was linear up
to absorbance = 1.1. The relative error in midrange was <2.5%. The quantity
of Al determined in soil extracts was shown for some soils to be strongly dependent
on the time of contact with the complexing reagents before extraction with butyl
acetate. This was attributed to the complexation of Al by organic matter in the
soil solutions. The fluorometric method was found to have a detection limi/t of
about 0.3 ppb Al. The fluorometric response was nearly linear in the most sensi-
tive range of the fluorometer but was less linear for higher Al concentrations.
The relative error was <8% except near the detection limit. There was no
264
-------
interference with either method from Na(+), K(+), Mg(2+), Ca(2+), Sr(2+), Ba(2+),
Fe(2+), Fe(3+), F(-), PO4(3-), S04(2-), and S03(2-) at the levels found in most
soil extracts.
78:07B-019
ELECTRON PROBE MICROANALYTICAL STUDIES OF PHOSPHORUS DISTRIBUTION WITHIN SOIL
FABRIC,
Qureshi, R.H., Jenkins, D.A., and Davies, R.I.
Agricultural University, Lyallpur, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 698-703, September-
October, 1978. 4 fig, 13 ref.
Descriptors: Phosphorus, Chemical analysis, Soil analysis. Soil tests. Analytical
techniques, Elements (chemical), Root zone, Voids, Iron, Nutrients.
Electron probe microanalysis was used to follow the distribution of phosphorus
and associated elements within soil features to establish the composition of the
immediate root environment. Various qualitative analytical modes of using the
instrument were described involving either specimen traverse or spectrometer
scanning with a static beam, line scanning, one-dimensional scanning, area
scanning, or successive rast counting. By these means phosphorus was found to
occur variously as discrete grains of rare-earth phosphates, in preferential
association with iron in iron/manganese concretions, as concentrations within
undifferentiated soil matrix and ferrans at void surfaces, and to be associated
with calcium in a fresh root and possibly with iron rather than calcium, aluminum,
or potassium in an old root.
78:076-020
ELECTRON PROBE MICROANALYSIS OF CALCITE GRAINS CONTAINING PHOSPHORUS IN SOIL,
Qureshi, R.H., and Jenkins, D.A.
Agricultural University, Lyallpur, Department of Soil Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 703-705, September-
October, 1978. 4 fig, 11 ref.
(See 78:02K-045)
78:078-021
MEASUREMENT OF FURROW INFILTRATION RATES MADE EASY,
Miller, D.E., and Rasmussen, W.w.
Federal Research, Science and Education Administration, Prosser, Washington,
United States Department of Agriculture.
Soil Science Society of America Journal, Vol. 42, No. 5, p 838-839, September-
October, 1978. 3 fig, 1 tab, 9 ref.
Descriptors: Infiltration rates, Infiltration, Furrow irrigation, Infiltrometers,
Computer programs, Measurement.
An irrigation system was developed for infiltration studies that utilized overflow
controls to maintain nearly constant inflow into irrigation furrows. Furrow out-
flow was measured with HS flumes equipped with water-level recorders. Data were
easily and rapidly converted to infiltration rates and cumulative infiltration
by a computer.
78:078-022
GRAVIMETRIC VS. VOLUMETRIC DETERMINATION OF WATER STORAGE IN VERTICALLY UNSTABLE
TILLAGE LAYERS,
Steinhardt, R. ,„•,„ ,.„.,:,,.,.
Institute of Soils and Water, Agricultural Research Organization, The Volcani
Center, Bet Dagan, Israel, Division of Soil Physics.
Soil Science Society of America Journal, Vol. 42, No. 5, p 836-837, September-
October, 1978. 1 tab, 14 ref, 5 equ.
Descriptors: Water storage, Soil water, Moisture content, Soil compaction,
Frost heaving, Drainage, Irrigation, Gravimetric analysis, Volumetric analysis,
Methodology.
265
-------
Methods of determining water storage (W) in a tillage layer of changing height
were analyzed to compare the effects of agrotechnical management on W. It
was shown that changes in W may be evaluated from a single estimate of the solid
mass per unit area at a state of reference and periodic observations of the
gravimetric water content of the tillage layer, which is equivalent to the usual
procedure of stable soils.
78:07B-023
DIRECT IN-FIELD MEASUREMENT OP NITROUS OXIDE FLUX FROM SOILS,
Ryden, J.C., Lund, L.J., and Focht, D.D.
California University, Riverside, Department of Soil and Environmental Science.
Soil Science Society of America Journal, Vol. 42, No. 5, p 731-737, September-
October, 1978. 2 fig, 5 tab, 29 ref.
Descriptors: Denitrification, Nitrates, Gas chromatography, Measurement,
Fertilization, Ozone, Methodology, Data collections.
A method was developed whereby nitrous oxide N20 effusing from a soil surface
could be contained and selectively trapped for subsequent analysis. The methodo-
logy proposed provides a direct measurement of N20 flux which is integrated over
the sampling period used. The methodology is sufficiently simple that it em-
bodies a monitoring capability which can be used to measure N20 evolution in
on-going agricultural practice. The method may also provide a basis for the
direct measurement of total N loss as a result of denitrification, if the further
reduction of N20 to N2 can be inhibited.
78:07B-024
FIELD TESTING OF SEVERAL NITROGEN AVAILABILITY INDEXES,
Fox, R.H., and Piekielek, W.P.
Pennsylvania State University, University Park, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 5, p 747-750, September-
October, 1978. 2 fig, 3 tab, 9 ref.
Descriptors: Nitrogen, Fertilization, Soil tests, Crop production, Chemical
analysis, Crop response, Corn (field), Laboratory tests.
Eight N availability indexes were correlated with the capability of eight
Pennsylvania soils to supply N to field-grown corn (Zea mays L.) in 1976 and 1977.
Boiling O.OlM CaC12 and 0.01M NaHC03-extractable N were both significantly correlated
at the 1% level (r = 0.86 and 0.77, respectively) with the N-supplying capability
of the soils from the combined 1976 and 1977 experiments. Autoclave-extractable
NH4-N and total soil N were significantly correlated with the soil supplying
capability at the 5% confidence level (r=0.70 and 0.68, respectively). Walkley-
Black soil organic matter, Soil NO3(-), and H2S04-extractable and KCl-extractable
N were not significantly correlated with N availability in the field. Though four
of the indexes were well correlated with the N availability in the soil, time and
expense necessary for these analyses may preclude their being used routinely by
soil testing laboratories.
78:078-025
REMOTE SENSING OF WATER LEVELS IN SMALL DIAMETER WELLS,
Lovell, A.D., Ellis, J.W., Bruce, R.R., and Thomas, A.W.
United States Department of Agriculture, Science and Education Administration,
Watkinsville, Georgia 30677.
Agricultural Engineering, Vol. 59, No. 10, p 44-45, October, 1978. 4 fig.
Descriptors: Water level recorders, Water level fluctuations, Water levels, Remote
sensing, Pressure head, Piezometers.
A remote sensing device was developed that measures water level changes in
potentiometer resistance. This device is capable to follow water levels in small-
diameter piezometer tubes installed at depth ranging from 125 cm to 305 cm and can
measure the water level to within about 5 mm.
266
-------
78:073-026
AUTOMATED SAMPLING ANALYSIS OF RURAL NONPOINT SOURCE WATER QUALITY,
Humenik, F.J., Bliven, L.F., Koehler, F.A., and Overcash, M.R.
North Carolina State University^ Raleigh, Department of Biological and
Agricultural Engineering.
Paper No. 78-2509, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 10 p. 5 fig, 4 tab, 18 ref, 2 equ.
Descriptors: Water quality, Water pollution, Water sampling, Water pollution
sources, Automation, Water yield, Ion transport, Base flow, Flow duration.
Automated sampling was employed to assess constituent (COD, TOC, TP, TKN, NO3-N,
and Cl) yields and concentrations from two Piedmont sites in Virginia and two
poorly-drained Coastal Plain sites in North Carolina within the Chowan River
watershed. These data were analyzed to provide a mechanistic interpretation
of subbasin processes. Characteristic Piedmont and Coastal Plain seasonal water
yield cycles which have winter maximums and summer minimums were related to
regional potential water yields (rainfall minus evapotranspiration). Large
water yield variations for subbasins within each region, however, were attributed
by physical differences between subbasins. Greater water yield from the
agricultural Piedmont site than from the forested Piedmont site reflected in-
creased cleared land plus greater channelization both on the basis of channel
density and channel gradient at the agricultural site. Elevated baseflow,
probably due to stream channelization, was the dominant factor contributing
to water yield differences between two Coastal Plain subbasins. Surface flow
COD, TOC, TP, TKN and N03-N concentrations were usually greater than baseflow
concentrations, but at the unchannelized Coastal Plain site the opposite case
prevailed and at all sites surface flow Cl concentrations were less than base-
flow concentrations. The seasonal concentration cycle displayed a summer
maximum and winter minimum and thus it was out of phase with the water yield
cycle.
78:078-027
MEASURING FLUMES OF SIMPLIFIED CONSTRUCTION,
Replogle, J.A., and Clemmens, A.J.
United States Water Conservation Laboratory, Science and Education Administration,
Phoenix, Arizona, Department of Agriculture.
Paper No. 78-2506, Presented at the 1978 Winter Meeting of the American Society of
Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 13 p. 10 fig, 3 tab, 15 ref.
Descriptors: Flumes, Measurement, Mathematical models, Flow measurement,
Irrigation canals, Critical flow, Construction costs.
Mathematical modeling was applied to optimize error control and construction
simplicity for the selection of a family of long-throated flumes, resembling
broad-crested weirs with a sloping approach ramp, for use in trapezoidal irrigation
canals. Alternate shapes and sizes were proposed for unlined canals with
extensions to sizes and shapes for limited application to watershed work.
78:076-028
SAMPLING AND CHEMICAL INTERPRETATION OF PRECIPITATION FOR MASS BALANCE STUDIES,
Lewis, W.M., and Grant, M.C.
Colorado University, Boulder, Department of Environmental Population and Organismic
Biology.
Water Resources Research, Vol. 14, No. 6, p 1098-1104, December, 1978. 2 fig,
1 tab, 40 ref.
Descriptors: Precipitation (atmospheric), Chemistry of precipitation, Sampling,
Chemical analysis, Rainfall, Rain gages, Design, Data collections.
From an analytical viewpoint, total dry and wet precipitation consists of three
fractions: (.1) dissolved materials in aqueous precipitation, (2) the water-
soluble component of dry precipitation, and (3) the water-insoluble component of
either wet or dry precipitation. Methods of precipitation collection and pro-
cessing greatly affect the separation of these components. A literature survey
267
-------
showed that fraction 3 has typically been ignored and that samplers currently in
use lead to a highly variable mixture of the three fractions. A literature survey
also showed that most collectors currently in use are of insufficient size to col-
lect samples large enough to support broad-spectrum analysis on a weekly basis. The
minimum satisfactory size of collectors was computed from (1) average rain chemistry,
(2) sensitivity of standard chemical tests for chemical species of biological in-
terest, and (3) volume required for each analysis. The computations showed that
collectors should have an area of at last 1200 sq cm in regions of average chemistry
and as much as 8300 sq cm in cold climates with minimal aqueous precipitation. A
design was given for a collector which combines large size with other desirable
features.
78:07B-029
SERIOUS INTERFERENCES IN THE DETERMINATION OF TRACE METALS IN SOILS BE FLAME AND
FLAMELESS ATOMIC ABSORPTION SPECTROMETRY,
Mubarak, A., Hageman, L., Howald, R.A., and Woodriff, R.
Montana College of Mineral Science and Technology, Butte, Department of Chemistry.
Soil Science Society of America Journal, Vol. 42, No. 6, p 889-891, November-December,
1978. 5 tab, 14 ref.
(See 78:02K-059)
78:078-030
OXYGEN FLUX MEASUREMENT IN UNSATURATED SOILS,
Rankin, J.M., and Sumner, M.E.
Malcomess Ltd., Isando, South Africa, Department of Agronomy.
Soil Science Society of America Journal, Vol. 42, No. 6, p 869-873, November-
December, 1978. 3 fig, 3 tab, 12 ref.
Descriptors: Oxygen, Soil gases, Diffusion, Aeration, Deaeration, Oxidation-reduc-
tion potential, Electrodes, Measurement, Instrumentation, Electrical resistance.
Because in unsaturated soil systems the plateau of the current-voltage curve is not
well developed or is absent, 02 reduction at the platinum microelectrode is not
diffusion controlled and consequently measured current depends continuously on
applied potential. To overcome this difficulty an 02 flux meter was designed which
carefully controls and measures the applied potential and enables the effective
potential at the electrode to be measured precisely. The instrument, which has
facilities for measuring soil electrical resistance, electrode redox potential, and
02 reduction current was fully described together with a circuit diagram. Because
the surface oxide condition of the microelectrode is crucial to reproducible results,
electrode pretreatment involving gentle abrasion in wet fine sand is necessary to
standardize conditions prior to measurement. The results showed that the instrument
is suitable for measuring 02 flux in unsaturated systems, and that measured current
was closely related to soil airspace.
78:07B-031
DETERMINATION OF THE APPARENT DISPERSION COEFFICIENT OF SOLUTES IN UNSATURATED SOIL,
Paetzold, R.F., and Scott, H.D. S
United States Department of Agriculture, Soil Conservation Service, National Soil
Survey Laboratory, Lincoln, Nebraska 68508.
Soil Science Society of America Journal, Vol. 42, No. 6, p 874-877, November-December,
1978. 3 fig, 1 tab, 14 ref, 16 equ,
(See 78:02K-062)
78:078-032
TO MARK SAMPLING EVENTS ON A RUNOFF HYDROGRAPH,
Johnson, A.T., Kort, R., and Ayars, J.E.
Maryland University, College Park, Department of Agricultural Engineering.
Agricultural Engineering, Vol. 59, No. 9, p 22-23, September, 1978. 2 fig.
Descriptors: Runoff, Hydrographs, Intermittent streams, Instrumentation, Stream
gages.
This article described how a Stevens Type F Water Stage Recorder can be modified
to make it more practical for runoff studies and to monitor streams where flow is
intermittent.
268
-------
78:078-033
THE PREDICTION OF MEAN MONTHLY SOIL TEMPERATURE FROM MEAN MONTHLY AIR
TEMPERATURE,
Toy, T.J., Kuhaida, A.J., and Mwnson, B.E.
Denver University, Denver, Colorado, Department of Geography,
Soil Science, Vol. 126, No. 3, p 181-189, September, 1978. 4 fig, 3 tab, 13 ref,
5 equ.
Descriptors: Soil temperature, Air temperature, Climatic data, Estimating equa-
tions.
Though soil temperature is important to a variety of earth science subdisciplines,
data are collected at few locations. This report presented simple, linear models
for estimating mean annual, seasonal, and monthly soil temperatures with reasonable
accuracy, using only air temperature data. A general equation based on all months
and all sample stations taken together, seasonal equations, and equations for
individual stations were provided. These models can be used to estimate soil
temperature from air temperature data collected by the National Weather Service
at stations throughout the United States.
78:07B-034
SOIL MOISTURE DETERMINATION USING MICROWAVE RADIATION,
Hankin, L., and Sawhney, B.L.
The Connecticut Agricultural Experiment Station, Box 1106, New Haven, Connecticut
06504.
Soil Science, Vol. 126, No. 5, p 313-315, November, 1978. 1 fig, 4 tab, 5 ref.
Descriptors: Moisture content, Soil moisture, Gravimetric analysis, Laboratory
tests, Laboratory equipment, Sampling, Microwaves, Moisture.
The advantages of microwave treatment over conventional heating are simplicity
of operation and speed, especially in experimental studies where changes in
design are necessary as experiment proceeds. A simplified method was reported
in this article for soil moisture determination by microwave ove using ordinary
filter paper folded into cups for holding the sample. Two soils, a heavy-
textured and a light-textured soil; and two fine clays, montmorillonite and
kaolinite were used in this study. By the method described in this paper, the
optimum heating time was found to be 6 minutes and about a 10 g sample appeared
to be most convenient for moisture determination by the method described in this
article.
78:078-035
MODIFICATIONS TO A SOIL OXYGEN DIFFUSION RATEMETER,
Bornstein, J., and McGuirk, M.
Maine University, Orono, Northeast Plant, Soil, and Water Laboratory.
Soil Science, Vol. 126, No. 5, p 280-284, November, 1978. 1 fig, 5 ref, 5 equ.
Descriptors: Aeration, Soil gases, Oxygen, Laboratory equipment, Diffusion,
Electrical resistance, Laboratory tests, Calibrations.
Recent efforts to relate soil aeration to crop production rely in part on soil
oxygen diffusion rate (ODR) measurements. The platinum microslectrode method is
often used to measure the soil ODR. The electrode current is easily interpreted
when the soil is saturated with water. When the soil is not saturated, the
interpretation of the electrode current depends on the effective potential applied
to the microelectrode. The effective potential cannot be measured directly, but
is calculated from several other measured quantities. The equation for obtaining
the effective potential is given for two types of ODR measurement systems. The
second type is commercially available and offers several advantages, but has
limited accuracy at low ODRs. Two modifications to the commerical system were
described, both of which greatly increase the accuracy of the system.
78:078-036
IN SITU HYDRAULIC CONDUCTIVITY OF A FRAGIPAN SOIL IN THE SOUTHERN COASTAL PLAINS,
Prasad, K.G., and Perkins, H.F.
Georgia University, Athens.
Soil Science, Vol. 126, No. 5, p 263-268, November, 1978. 3 fig, 2 tab, 21 ref.
269
-------
Descriptors: Hydraulic conductivity, Hydrologic properties, Soil horizons,
Coastal plains, Moisture availability. Soil water. Perched water.
More than 250,000 ha of soils having a fragipan or fragic properties occur in
the Southern Coastal Plains Soil Province. These soils have moderate to severe
land use restrictions, partially due to perched water, slow permeability, and
restricted root growth. The Cowarts soil (Fragic Paleudults; fine-loamy,
siliceous, thermic family), which is developed from marine sediments, was se-
lected to determine in situ hydraulic conductivities and related hydrological
properties. The moderately well-expressed fragipan has higher bulk density,
less pore space, smaller pores, less available water, and lower hydraulic
conductivity values than horizons above or below the pan. With an increase in
hydraulic head, an increase in hydraulic conductivity was less in the fragipan
than in associated horizons.
270
-------
SECTION XXXIII
RESOURCES DATA
EVALUATION, PROCESSING AND PUBLICATION (GROUP 07C)
78:07C-001
ESTIMATION OF AGRICULTURAL NONPOINT LOADS TO THE WAKARUSA RIVER BASIN USING THE
"NONPOINT CALCULATOR",
Davis, M.J., and Nebgen, J.W.
Midwest Research Institute, Kansas City, Missouri.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference, p 525-
550. 1 fig, 14 tab, 2 ref, 7 equ.
(See 78:05G-063)
271
-------
SECTION XXXIV
ENGINEERING WORKS
STRUCTURES (GROUP 08A)
78:08A-001
IRRIGATION PIPE REPAIR CUTS COSTS,
Larsen, R., Associate Editor.
Irrigation Age Magazine.
Irrigation Age, Vol. 12, No. 7, p 6, April, 1978. 1 fig.
Descriptors: Pipelines, Pipes, Repairing, Cost comparisons, Colorado, Equipment,
Instrumentation, Maintenance, Engineering structures.
The experience of a Colorado farmer who designed a repair operation for damaged
aluminum irrigation pipes was discussed. Repairing damaged pipes has proved to
be considerably cost-effective in comparison to the costs for new pipes.
78:08A-002
TRENCHLESS DRAINAGE,
Reeve, R.C.
Advanced Drainage Systems, Incorporated, Columbus, Ohio.
Paper No. 78-2042, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 9 p. 9 fig.
Descriptors: Subsurface drainage, Subsurface drains, Drainage practices,
Trenches, Maintenance costs, Installation, Groundwater, Drainage.
Following the development of corrugated plastic tubing and automatic laser
grade control in the 1960s, a dramatic move to "trenchless" drainage has taken
place in the 1970s. Low maintenance costs and high installation rates (up to
50,000 ft per day) has given the competitive edge that is shifting the industry
from trench to "trenchless" drainage.
78:08A-003
SEDIMENT TRAPS IN CHANNELS—DESIGN PROCEDURES AND PERFORMANCE,
Konwinski, G.R.
Soil Conservation Service, East Lansing, Michigan.
Paper No. 78-2561, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 6 p. 2 fig.
(See 78:02J-028)
78:08A-004
DEVELOPMENT AND APPLICATION OF SEDIMENT BASINS IN MARYLAND,
Boysen, S.M.
Soil Conservation Service, College Park, Maryland, United States Department of
Agriculture.
Paper No. 78-2562, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 13 p. 2 fig, 9 ref, 1 append.
Descriptors: Sediment control. Trap efficiency, Soil erosion, Design criteria.
Design standards. Specifications, Sediment yield, Detention reservoirs, Skimming.
Sediment basins are an important part of the sediment control program in Maryland.
Criteria were presented for estimating trap efficiency of basins. Experiences
and results of field observations were presented. Standards and specifications
prepared by the Soil Conservation Service for sediment basins in Maryland were
attached.
272
-------
SECTION XXXV
ENGINEERING WORKS
HYDRAULICS (GROUP 08B)
78:08B-001
APPLICABILITY OF KINEMATIC AND DIFFUSION MODELS,
Ponce, V.M., Li, R.M., and Simons, D.B.
Colorado State University, Fort Collins, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY3, Proceedings Paper 13635, p 353-360, March, 1978. 4 fig, 1 tab, 5 ref,
3 append.
Descriptors: *Diffusion, *Model studies, *0pen channels, *Kinematic models,
Dynamics, River beds, Waves (water), Saint Venant equation, Wave period,
Mathematical studies.
The applicability of the kinematic and diffusion models of open channel flow
was assessed by comparing the propagation characteristics of sinusoidal •
perturbations to the steady uniform flow for the kinematic, diffusion, and
dynamic models (the dynamic model is that based on the complete Saint Venant
equations). The comparison allowed the determination of inequality criteria
that need to be satisfied if the kinematic or diffusion models are to simulate
the physical phenomena within a prescribed accuracy. It was shown that bed
slope and wave period (akin to wave duration in waves of shape other than
sinusoidal) are the important physical characteristics in determining the
applicability of the approximate models. Larger bed slopes or long wave periods,
or both, will satisfy the inequality criteria. In practice, larger bed slopes
are those of overland flow, and long wave periods are those corresponding to
slow-rising flood waves.
78:08B-002
DIRECT SOLUTION TO PROBLEMS OF OPEN CHANNEL TRANSITIONS,
Vittal, N.
Roorkee University, India, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY11, p 1485-1494, November, 1978. 6 fig, 1 ref, 17 equ, 2 append.
Descriptors: Transition flow, Open channel flow, Subcrltical flow, Critical flow,
Open channels, Hydraulic design, Culverts, Aqueducts, Graphical methods, Flow
characteristics.
The existing methods of solving open channel transitions involve trial-and-error
solution of higher degree equations. In this paper, a method was proposed which
presents unique dimensionless discharge-depth relationships for exponential,
trapezoidal, and circular channels that facilitate direct solutions even to com-
plex problems of contracting open channel transitions. The steps enumerated in
the examples demonstrated the simplicity of the method. It was recommended that
enlarged design charts of the proposed graphical relations are used in actual
design for accuracy. Alternatively, design tables prepared from given equations
may also be used.
78:088-003
HYDRODYNAMIC PERFORMANCE OF PIPE UNDERDRAINS,
Mevorach, J., and Zanker, K.
Technion-Israel Institute of Technology, Haifa, Department of Hydrodynamics and
Hydraulic Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR1, Proceedings Paper 13636, p 127-142, March, 1978.
15 fig, 4 ref, 2 append.
273
-------
Descriptors: *Valves, *Hydraulic valves, *Drainage, Channels, Flow, Drains,
Pipes, Sediments, Groundwater, Flexible-flap drain valves.
Theoretical analysis and laboratory investigations of flexible-flap drain valve
in high-velocity open channel flow were presented. Main hydrodynamic
characteristics of the valve are: (1) Radial diffuser action, which prevents
the valve from opening at low pressures; and (2) uplift forces, caused by high-
velocity flow in the channel, helping the valve to open. The most severe con-
dition for the valve operation is when there is little or no flow in the
channel, but there is still high groundwater table around the channel. Flap-
valves are found suitable for use in high-velocity flows, provided that the
ratio, R sub 2/R sub 1, between the circular flap and the valve opening is kept
as low as compatible with engineering considerations.
78:08B-004
SIMULATED FLOW RATE REQUIREMENTS FOR SOME FLUSHING EMITTERS,
Solomon, K., and Bezdek, J.C.
Utah State University, Logan, Department of Mathematics.
Paper No. 78-2016, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p. 3 fig, 5 tab,
8 ref, 1 equ.
Descriptors: Flow rates, Simulation analysis, Hydraulic models, Irrigation,
Lateral conveyance structures, Model studies, Irrigation systems, Hydraulic
properties, Water pressure.
A steady state simulation model was used to study the hydraulic behavior of
trickle irrigation laterals and manifolds employing automatic flushing emitters.
The influence of emitter characteristics and design values such as emitter
operating pressure, flow rate, spacing, and lateral length were considered.
78:088-005
TRICKLE IRRIGATION TUBING HYDRAULICS,
Watters, G.Z., and Keller, J.
Utah State University, Logan, Department of Civil and Environmental Engineering.
Paper No. 78-2015, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 18 p. 16 fig, 2 tab,
12 ref, 14 equ.
Descriptors: Pipe flow, Hydraulic properties, Irrigation systems, Head loss,
Darcy-Weisbach equation, Moody resistance diagrams, Pipelines, Hazen-Williams
equation. Analytical techniques, Graphical methods.
Laboratory experiments show that the Darcy-Weisbach equation for hydraulically
smooth pipes should be used to compute friction losses in PVC pipe and plastic
tubing. Simple formulas are presented to accomplish this. Graphs to find
equivalent lengths for emitter connection losses are given. Techniques for
calculating head losses in multiple-outlet lines are presented.
78:088-006
PRESSURE LOSSES ACROSS TRICKLE IRRIGATION FITTINGS AND EMITTERS,
Howell, T.A., and Barinas, F.A.
Texas A & M University, College Station, Department of Agricultural Engineering.
Paper No. 78-2014, Presented at the 1978 Summer Meeting of the American Society
of Agricultural Engineers, June 27-30, 1978, Logan, Utah, 12 p. 16 fig, 1 tab,
7 ref, 10 equ.
Descriptors: Energy loss, Energy gradient. Irrigation design, Flow rates,
Lateral conveyance structures. Pipelines, Pressure conduits, Irrigation systems,
Water pressure, Hazen-Williams equation.
Pressure losses across on-line trickle emitters were measured. The energy losses
as expressed by the equivalent length of pipe were described by a power function.
The empirical coefficients were related to the emitter characteristics of pro-
trusion depth and area. Lateral design procedures and examples are presented.
Pressure losses across PVC and PE barbed fittings were measured.
274
-------
78:088-007
SIZE DETERMINATION OF PARTLY FULL CONDUITS,
Mussalli, Y.G.
Stone and Webster Engineering Corporation, Boston, MA. Hydraulic Division.
Journal of Hydraulic Division, American Society of Civil Engineers, Vol. 104,
No. HY7, Proceedings Paper 13862, p 959-974, July, 1978. 13 fig, 2 tab, 9 ref.
Descriptors: *Air-water interfaces, *Flow control, *Free surfaces, *Air-water
interactions, Surface runoff, vibrations, Hydraulics, Mathematical studies,
Equations, Water tunnels.
The transition from partly full to full pipe (sealing) is accompanied by
vibrations of the structure and surging of the flow. The experimental study was
done in a 4-in (100-mm) square conduit with three different circular bends, with
various deflectors, and with various concentrations of air. Sealing depends on
the Froude number of the flow. To maintain partly full flow, more space is
needed above the water-flow area with an increase of Froude number. With short-
tube control, the ratio of the radius of curvature along the center line to the
bend diameter and the deflector thickness at the crown of the bend determine the
water-flow area in the horizontal conduit. Ventilation of the horizontal con-
duit delays sealing, while aeration of the water flow hastens sealing. With
weir control, waves on the flow surface hasten sealing, and highly aerated flow
delays sealing. Ratios of radius of curvature to the bend diameter larger than
2.0 were recommended since they generate fewer waves.
78:08B-008
VARIED FLOW FUNCTIONS FOR CIRCULAR CHANNELS,
Nalluri, C., and Tomlinson, J.H.
Newcastle-upon-Tyne., England, Department of Civil Engineering.
Journal of Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY7, Proceedings Paper 13889, p 983-1000, July, 1978. 2 fig, 4 tab, 11 ref.
Descriptors: *Backwater, *Channels, *Flow, Conduits, Flow profiles. Gradually
varied flow, Open channels, Pipes, Hydraulics, Backwater profiles.
Hydraulic engineers often are required to compute backwater curves, and the
existing methods cannot be applied accurately to closed conduits as the flow
approaches the crown. This paper reviewed the Keifer and Chu method which uses
the dimensionless parameter Q/QCAP. A new approach was developed to compute
backwater curves in circular channels in which the factor Q/QCAP is removed so
that errors are not introduced by having to interpolate these values. This new
method is applicable for all possible bed slope conditions (horizontal, adverse),
which is a distinct advantage over the other existing techniques. Semigraphical
methods also were suggested to increase the speed of computation of backwater
curves.
78:088-009
AMERICAN DEVELOPMENTS IN HYDRAULIC MEASUREMENT,
Ripken, J.F.
Minnesota University, Minneapolis, St. Anthony Falls Hydraulic Laboratory.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY6, Proceedings Paper 13821, p 857-868, June, 1978. 1 ref, 1 append.
Descriptors: *Measurement, "Instrumentation, "Discharge (water), *Flow
measurement, "History, Wiers, Electronic equipment, Orifices, Hydrometry, Flumes.
A historical summary is presented of American contributions to hydraulic mea-
surement of streamflow for the period 1776-1976. The development and interrelation
of conduit flow measuring devices, together with open channel measuring devices,
was included in this update of previous historical summaries. The narrative
style and historical sequencing is a useful complement to the more specific
"Bibliography on Discharge Measurement Techniques."
78:088-010
HYDRAULIC FRICTION LOSS IN SMALL DIAMETER PLASTIC PIPELINES,
Hughes, T.C., and Jeppson, R.W. ..,,,. .
Utah State University, Logan, Department of Civil and Environmental Engineering.
275
-------
Water Resources Bulletin, Vol. 14, No. 5, p 1159-1166, October, 1978. 1 fig,
1 tab, 2 ref, 4 equ, 1 append.
Descriptors: Plastic pipe, Hydraulic conduits, Pipe flow, Design, Hazen-
Williams equation, Darcy-Weisbach equation, Reynolds number, Flow friction,
Water supply. Moody resistance diagrams.
Field measured friction losses in three one-mile sections of small diameter pvc
pipe which have been in service for ten years is reported. Hazen-Williams and
Darcy-Weisbach equations were examined to provide a framework for comparing Hazen-
Williams coefficients recommended by pipe manufacturers to those obtained by the
field measurements. It was concluded that the Hazen-Williams coefficient of 150
recommended by most pvc pipe manufacturers is too high for the diameter-velocity
combinations encountered in rural dead-end small diameter lines. The measured
coefficients averaged 133 which is close to that predicted by superimposing
Hazen-Williams coefficients on the Moody diagram from which the friction factor
for the Darcy-Weisbach equation is obtained.
78:08B-011
KALMAN FILTER IN OPEN CHANNEL FLOW ESTIMATION,
Chiu, C.L., and Isu, E.O.
Pittsburgh University, Pennsylvania, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY8, Proceedings Paper 13946, p 1137-1152, August, 1978. 9 fig, 19 ref.
Descriptors: *0pen channels, *Model studies, *Open channel flow, *Kalman filter.
Mannings equation, Estimating, Resistence coefficients, Manning formula,
Open channel hydraulics, Hydraulics.
In computing water surface profiles in open channels, uncertainties often arise
in selection of resistance coefficients, such as Manning's n. In this paper
the Kalman filtering approach was developed to deal with such uncertainties.
This approach combined a mathematical system model and an observation model.
The former consists of (1) stochastic nonlinear differential equation governing
the steady one-dimensional open channel flow; and (2) one of three possible
stochastic differential equations expressing Manning's n (constant, function of
the location of channel cross section, or function of both the location and
the water depth). The observation model simply shows the observed water depth
as the sum of "true water depth" and "error". The estimation technique was
tested for its accuracy in generating estimates of water depth and Manning's n
at several different schemes of sampling or measuring water depths. Results with
Kalman filtering were compared with two parallel methods normally used today.
78:088-012
AIR-WATER FLOW IN COARSE GRANULAR MEDIA,
Hannoura, A.A., and McCorquodale, J.A.
Windsor University, Ontario, Department of Civil Engineering.
Journal of the Hydraulic Division, American Society of Civil Engineers, Vol. 104,
No. HY7, Proceedings Paper 13888, p 1001-1010, July, 1978. 5 fig, 1 tab, 15 ref.
Descriptors: *Breakwaters, *Darcys law, *Granules, *Porous media, *Coastal
engineering, Entrainment, Hydraulic conductivity, Waves (water). Hydraulics,
Air-water interfaces.
Air may be entrained in the flow in porous shore structure under wave action.
Three conceptual models for two-phase flow in ducts were adapted to describe
flow in coarse granular media. These are the homogeneous bubbly drift-flux,
and slug drift-flux models. An experimental study was undertaken to check
the three models against air-water flow in three coarse granular porous media.
The best model was chosen based on its agreement with the experimental head
drop results. On this basis, the slug flow drift-flux model was recommended to
calculate the effect of entrained air on the hydraulic conductivity for co-
current and counter current flows.
276
-------
78:088-013
DISPERSION IN RIVERS AS RELATED TO STORAGE ZONES,
Sabol, G.V., and Nordin, C.P.
New Mexico State University, University Park, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers,. Vol.
104, No. HY5, Proceedings Paper 13758, p 695-708, May, 1978. 4 fig, 3 tab,
26 ref, 2 append.
Descriptors: *Dispersion, *Rivers, *Reservoirs, *Model studies, Mathematical
models, Suspended solids, Markov processes, Theoretical analysis, Sedimentation,
River flow.
Longitudinal dispersion was considered as a simple stochastic process in which
a particle travels random time periods at constant velocity, with travel
period separated by random time periods during which the particle is trapped
in storage zones. The average number per unit time of entries into storage
was considered to be a function of time. The resulting model was a nonhomo-
geneous compound Poisson process defined by three parameters. Methods for
estimating the parameters were given, and predicted concentration distributions
were shown to agree reasonably well with observed field data.
277
-------
SECTION XXXVI
ENGINEERING WORKS
HYDRAULIC MACHINERY (GROUP 08C)
78:08C-001
COLORADO PUMP TESTS SHOW HOW TO MAKE BIG DOLLAR SAVINGS,
Ross, R.
Irrigation Age, Vol. 12, No. 6, p 8-9+, March, 1978. 2 fig.
Descriptors: ^Irrigation operation and maintenance, *Pumping, Energy, Costs,
Efficiencies, Electric power costs, Electric power rates, Conservation.
A recent pump testing program in Colorado has demonstrated a huge potential for
electrical energy savings in that state if the average efficiency of irrigation
pumps could be upgraded. Program researchers have maintained that efficiencies
of 65% are readily achievable by proper pump selection and care, and significant
number of systems tested were found to perform at this level. However, average
efficiencies in approximately 600 systems tested were only about 45% for open
discharge systems and 56-60% for sprinklers. Various remedial measures can be
taken to improve pump efficiency, such as adjustment of the impeller, replace-
ment of worn parts, proper sizing, improved well construction, and modification
of operating procedures. Unfortunately, present electrical rate structures
frequently discourage such measures. Net savings in a declining block rate
structure, for example, may be to low to offset the capital cost of upgrading
the irrigation system, thus the farmer's decision is not to repair the pump.
If irrigation power rates were reformulated so that cost to the farmer were
closer to the actual average cost per kwh, then the economic incentive to con-
serve energy would be enhanced.
278
-------
SECTION XXXVII
ENGINEERING WORKS
ROCK MECHANICS AND GEOLOGY (GROUP 08E)
78:08E-001
DESIGN UNDER STOCHASTIC GROUNDWATER FLUCTUATION,
Bogardi, I., and Duckstein, L.
Arizona University, Tucson, Department of Hydrology and Water Resources.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 104,
No. HY1, Proceedings Paper 13499, p 59-74, January, 1978. 4 fig, 3 tab, 22 ref,
4 append.
Descriptors: *Aquifers, *Groundwater, *Concrete structures, *Stochastic processes,
*Failure (mechanics), "Hungary, *Danube River, *Budapest (Hungary), Bivariate
analysis, Decision theory.
A foundation is to be protected against the harmful effects of sulfur groundwater,
whose piezometric head fluctuates in a random manner. The stochastic process
forms a partial duration series, where the jth event is defined by the maximum
exceedance above the foundation floor, the duration and interarrival time until
the (j + l)st event. To protect the structure against possible damage by high
levels of groundwater with substantial sulfate concentration, it is possible to
make four decisions, corresponding to waterproofing or using special sulfate
resistant concrete or both, or providing no protection. The annual cost and
expected loss associated with each of these four decisions were calculated with
the help of explicit expressions. Sensitivity of the decision to sample, model,
and economic uncertainty was analyzed as well as the possibility of using a
Bayesian approach to account for sample uncertainty.
279
-------
SECTION XXXVIII
ENGINEERING WORKS
MATERIALS (GROUP 08G)
78:080-001
ASPHALT-CRUMB RUBBER WATERPROOFING MEMBRANE,
Frobel, R.K., Jimenez, R.A., Cluff, C.B., and Morris, G.R.
Arizona University, Tucson, Water Resources Research Center.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 104, No. IR1, p 43-58, March, 1978. 10 fig, 1 tab, 11 ref,
4 equ, 1 append.
Descriptors: Linings, Reservoir leakage, Seepage, Seepage control, Waterproofing,
Asphaltic concrete, Laboratory tests.
A mixture of asphalt cement mixed with crumb-rubber (asphalt-rubber) has been
used successfully in highway construction for several years in Arizona and other
states. This paper describes laboratory tests on asphalt-rubber and includes
preliminary results of an actual reservoir lining application.
78:08G-002
PREDICTION OF DEFLECTION FOR CORRUGATED PLASTIC TUBING,
Fenemor, A.D., Bevier, B.R., and Schwab, G.O.
Ohio Agricultural Research and Development Center, Columbus, Department of
Agricultural Engineering.
Paper No. 78-2542, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 13 p. 4 fig, 3 tab, 13 ref, 12 equ.
Descriptors: Subsurface drains, Plastic pipes, Failure (mechanics), Deflection,
Pipes, Tubes, Drainage, Subsurface drainage, Installation, Soil tests.
Measured deflections of tubing buried five years ago in a silty clay showed that
the soil provides practically no side support against deflection. With measured
deflection lag factors, the Iowa formula was the best of four methods for pre-
dicting deflection. Recommended maximum depths of burial are tabulated for
tubing up to 381 mm diameter.
78:080-003
FAILURE CRITERIA FOR CORRUGATED-PLASTIC DRAIN TUBING,
Walker, P.N., Armstrong, C.L., and Singh, P.N.
Illinois University, Urbana, Department of Agricultural Engineering.
Paper No. 78-2439, Presented at the 1978 Winter Meeting of the American Society
of Agricultural Engineers, December 18-20, 1978, Palmer House Hotel, Chicago,
Illinois, 13 p. 8 fig, 2 tab, 5 ref, 8 equ.
Descriptors: Plastic pipes, Subsurface drains, Failure (mechanics), Tubes,
Drainage, Subsurface drainage. Pipes, Deflection, Installation.
Results from hydraulic-capacity, pipe-stiffness, and live-load carrying-capacity
tests of permanently deflected drain tubing are presented. These tests are
part of a continuing effort to define failure criteria for plastic drain tubing. -
280
-------
SECTION XXXIX
MANPOWER, GRANTS, AND FACILITIES
EDUCATION - EXTRAMURAL (GROUP 09A)
78:09A-001
ASCE MET SECTION STRIVING TO MAKE CIVIL ENGINEERING. CURRICULA MORE PRACTICE-
ORIENTED,
Khera, R.P.
New Jersey Institute of Technology, Newark, Department of Civil Engineering.
Civil Engineering, Vol. 48, No. 1, p 75, January, 1978.
Descriptors: Civil engineering, Engineering education. Education, Engineering,
Evaluation.
Concerned with deficiencies in civil engineering education and the limitations
of the ECPD evaluation procedures, the ASCE Metropolitan Section Committee on
Engineering Education set out to upgrade and monitor civil engineering education.
A poll of Met Section members showed a desire for change in the direction of
civil engineering education. Experimental review program of undergraduate
civil engineering education was approved by the Met Section Board in April, 1968.
It contemplated periodic visits to each of the undergraduate civil engineering
departments in the Metropolitan area by a team of ASCE members. This article
discusses in brief about the activities of the ASCE Met Section, the purpose it
has served, and the procedure it follows to attain its objectives.
281
-------
SECTION XL
SCIENTIFIC AND TECHNICAL INFORMATION
ACQUISITION AND PROCESSING (GROUP 10A)
78:10A-001
NATIONAL CONFERENCE ON MANAGEMENT OF NITROGEN IN IRRIGATED AGRICULTURE,
Pratt, P.F., Editor.
Sponsored by U.S. National Science Foundation, U.S. Environmental Protection
Agency, University of California.
Proceedings of National Conference on Management of Nitrogen in Irrigated
Agriculture, California University, Sacramento, California, p 1-442, May 15-18,
1978. 49 fig, 59 tab, 371 ref, 26 equ.
Descriptors: Nitrogen, Nitrogen cycle, Nitrates, Irrigated land, Water quality,
Water management (applied), Conferences.
These Proceedings represent a National Conference on Nitrogen Management in
Irrigated Lands, designed to bring together users representing a diversity of
interests throughout the country for an integrated review of the findings from
the comprehensive national research effort. The accumulated information needs
to be utilized as fully as possible by the many individuals and organizations
making decisions in current water quality planning. This will help ensure the
emergence of appropriate and viable solutions to our water quality problems —
solutions that are sensitive to both local and national needs and priorities.
282
-------
SECTION XLI
SCIENTIFIC AND TECHNICAL INFORMATION
SECONDARY PUBLICATION AND DISTRIBUTION (GROUP IOC)
78:10C-001
SELECTED IRRIGATION RETURN FLOW QUALITY ABSTRACTS 1976,
Skogerboe, G.V., Smith, S.W., and Walker, W.R.
Colorado State University, Fort Collins, Colorado, Department of Agricultural
and Chemical Engineering.
Publication No. EPA-600/2-78-042, March, 1978. 311 p.
Descriptors: Fertilizers, Irrigated land, Salinity, Return flow.
Research related to the quality of irrigation return flow is being conducted at
numerous institutions throughout the western United States. Related work is
also underway at other institutions in the United States, as well as other
portions of the world. Approximately 100 sources of material have been
searched for articles pertinent to the National Irrigation Return Flow Research
and Development Program. These articles describe water quality problems re-
sulting from irrigated agriculture, potential technological solutions for
controlling return flows, recent research pertinent to return flow investiga-
tions, and literature associated with institutional constraints in irrigation
return flow quality control. The first annual issue SELECTED IRRIGATION RETURN
FLOW QUALITY ABSTRACTS covered publications printed in 1968 and 1969, while
the second annual issue lists publications printed in 1970 and 1971, the third
annual issue covers literature published in 1974 and 1975. This annual issue
lists publications printed in 1976. This report was submitted in fulfillment
of Grant Number R-800426 under the sponsorship of the Office of Research and
Development, Environmental Protection Agency.
78:10C-002
GROUNDWATER POLLUTION. PART 2. POLLUTION FROM IRRIGATION AND FERTILIZATION.
VOL. 2. 1977-JANUARY, 1978. (CITATIONS FROM THE NTIS DATA BASE),
Brown, R.J., Editor.
National Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161.
NTIS/PS-78-0141, February, 1978. 65 p.
Descriptors: Abstracts, Bibliographies, Groundwater, Water pollution, Irrigation,
Fertilization, Water pollution control, Return flow, Research and development,
Groundwater recharge.
The bibliography contains abstracts of Federally-funded research covering aspects
of groundwater pollution from irrigation and fertilization. The reports in-
clude topics dealing with the pollution from sewage and waste water irrigation,
land spreading of sludges and solid wastes, nitrate and phosphate accumulation
in soils, pollution control and abatement planning, salt build-up from irrigation,
the use of tile drains in groundwater pollution control, and groundwater recharge
studies.
78:10C-003
THE PESTICIDE CONTENT OF SURFACE WATER DRAINING FROM AGRICULTURAL FIELDS—A REVIEW,
Wauchope, R.D.
Southern Weed Science Laboratory, Science and Education Adminstration, Federal
Research, United States Department of Agriculture, Stoneville, Mississippi 38776.
Journal of Environmental Quality, Vol. 7, No. 4, p 459-472, October-December, 1978.
3 fig, 4 tab, 69 ref.
Descriptors: Agricultural runoff, Surface runoff, Runoff, Pesticides, Water
quality, Water pollution, Herbicides, Insecticides, Reviews.
283
-------
The literature on pesticide losses in runoff waters from agricultural fields was
reviewed. For the majority of commercial pesticides, total losses were found to
be 0.5% or less of the amounts applied, unless severe rainfall conditions occur
within 1-2 weeks after application. Exceptions were noted for the organochlorine
insecticides, which might lose about 1% regardless of weather pattern because of
their long persistence; and soil surface-applied, wettable-powder formulations
of herbicides, which might lose up to 5%, depending on weather and slope, be-
cause of the ease of washoff of the powder. The effects of erosion control
practices on losses of various types of pesticides were documented. The behavior
and fate of pesticides in streams receiving runoff was not clearly determined
from the literature. It was concluded that information on such factors as time
and distance of impact of a given runoff event, ability of local ecosystems to
recover from transient pesticide concentrations, and dissipation or concentration
processes in aquatic ecosystems will have to be obtained before "edge-of-field"
pesticide losses can be related to water quality in receiving waters.
78:10C-005
CHOICES IN IRRIGATION MANAGEMENT,
British National Committee.
International Commission on Irrigation and Drainage.
ICID Bulletin, Vol. 27, No. 2, p 62-64, July, 1978.
Descriptors: Water management (applied), Irrigation, Groundwater, Irrigation
programs, Pricing, Agriculture, Crop production. Water demand, Project post-
evaluation.
A "workshop" on choices in irrigation management was organized by the Agricultural
Administration Unit of the Overseas Development Institute and held at the Univer-
sity of Kent, Canterbury. The workshop was attended by 35 participants, of whom
12 came from eight different countries in Asia, Africa and Latin America. The
majority of these had extensive first-hand experience of irrigation management
at project level. Twenty-one papers were presented and discussed. This paper
is a summary of these 21 papers discussed under several categories of irrigation
management.
78:10C-006
ANNOTATED BIBLIOGRAPHY FOR WATER QUALITY MANAGEMENT, FIFTH EDITION,
Hurd, M.
Water Quality Management Information Center, Program Management Branch, Water
Planning Division (WH/554), Washington, D.C. 20460.
EPA Report, Division of Water Planning, Washington, D.C., April, 1978. 64 p.
Descriptors: Bibliographies, Abstracts, Water quality. Water quality act, Water
quality control, Return flow, Water pollution, Water management (applied),
Waste water (pollution), Waste water treatment.
This bibliography was prepared by U.S. Environmental Protection Agency to assist
those agencies engaged in water quality management planning. The references
cited have been selected for their applicability to 208 planning and for their
availability. Each reference is followed by a short abstract, and whenever
possible, by detailed price and ordering information.
78:10C-007
BEST MANAGEMENT PRACTICES FOR AGRICULTURE AND SILVICULTURE,
Loehr, R.C., Haith, D.A., Walter, M.F., and Martin, C.S., Editors.
Cornell University, Ithaca, New York, College of Agriculture and Life Sciences.
Proceedings of the 1978 Cornell Agricultural Waste Management Conference. 154
fig, 159 tab, 490 ref, 57 equ.
(See 78:05G-071)
284
-------
SECTION XLII
AUTHOR INDEX
Aase, J.K.
78:020-006
78:07B-007
Abbott, J.L.
78:02K-021
Abede, B.
78:020-026
Abrol, I.P.
78:02G-023
Acharya, C.L.
78:02G-023
Adams, J.A.
78:021-015
Adams, J.E.
78:04A-017
Adrian, D.D.
78:05A-008
Adriano, D.C.
78:021-024
Aflatouni, M.
78:021-034
Aggelides, S.
78:020-067
Agri. Engineering
78:06E-005
Agron, N.A.
78:02K-006
Ahlert, R.C.
78:058-014
Akiri, B.
78:078-010
Al-Layla, M.A.
78:05G-020
Alberts, E.E.
78:058-008
Alemu, A.
78:03F-002
Alexander, G.H.
78:03F-066
Alexander, G.V.
78:02K-072
Alexander, M.
78:058-054
78:050-005
Ali, S.M.A.
78:03F-097
Aljibury, F.K.
78:03F-077
78:03F-080
Allen, S.E.
78:021-007
Allmaras, R.R.
78:021-008
78:07B-005
Alt, K.F.
78:068-010
Alvarez, D.
78:05G-016
Alvi, A.A.
78:03F-040
Anunon, D.C.
78:06A-016
Andersen, J.C.
78:05G-035
78:05G-075
Anderson, A.
78:02G-031
Anderson, L.W.J.
78:058-048
Anderson, O.E.
78:020-037
Anderson, T.D.
78:058-049
Archer, E.
78:04A-010
Ardekani, E.R.
78:020-029
Ariathurai, R.
78:02J-002
Armstrong, C.L.
78:080-003
Aronsson, G.
78:02J-014
Arulanandan, K.
78:02J-002
Ashcroft, G.L.
78:021-025
285
Ashley, D.A.
78:021-001
Avnimelech, Y.
78:05G-002
Ayars, J.E.
78:078-032
Ayers, R.S.
78:03F-015
78:058-020
Ayres, G.E.
78:03F-108
Bailey, G.W.
78:040-003
78:050-047
78:06A-003
Baker, D.E.
78:078-004
Baker, F.G.
78:02G-028
Baker, J.L.
78:05A-020
78:05G-029
Bakr, A.A. .
78:02F-007
78:02F-023
Baligar, V.C.
78:021-021
78:021-023
78:02K-026
78:02K-070
Bar-Yosef, B.
78:02K-004
78:02K-037
78:07B-010
Barber, S.A.
78:021-012
78:021-021
78:021-023
78:02K-026
78:02K-070
Barefoot, A.D.
78:03F-097
Barfield, B.J.
78:02J-009
78:02J-022
Barinas, F.A.
78:088-006
-------
Barkely, P.W.
78:03F-011
Barker, J.
78:02F-026
Barnes, P.L.
78:02G-060
Barnhisel, R.I.
78:02J-022
Barrett, J.W.H.
78:03F-031
Bartelt, G.E.
78:040-001
Bartsch, A.F.
78:050007
Batu, V.
78:02G-009
78:02G-044
Bauder, J.W.
78:021-006
Bauer, A.
78:021-006
78:03F-001
Baughman, G.L.
78:05B-030
Bayazit, M.
78:02J-016
Bear, J.
78:02F-010
Beauchamp, E.G.
78:02F-002
Beck, L.A.
Beese, F.
78:056-023
78:02K-015
Ben-Asher, J.
78:02G-041
78:03F-007
78:03F-026
Bendixen, W.E.
78:03F-010
Bennett, J.P.
78:07B-006
Benton, A.R., Jr.
78:020-004
Benz, L.C.
78:03F-125
Berkowitz, S.J.
78:06E-015
Berle, P.A.A.
78.-05G-068
Bettany, J.R.
78:021-033
78:02K-055
Beutel, J.
78:03F-080
Bevier, B.R.
78:08G-002
Beyerlein, D.C.
78:05G-065
Bezdek, J.C.
78:086-004
Bezdicek, D.F.
78:02G-026
Bhuiyan, s.'I.
78:03F-062
Bielorai, H.
78:021-003
78:030-004
78:03F-095
Biggar, J.W.
78:03F-015
Binder, C.W.
78:05G-011
Bingham, F.T.
78:021-015
Biswas, C.R.
78:050-021
Black, J.D.F.
78:021-002
Blackard, J.
78:040-004
Blair, J.
78:03F-035
78:03F-047
Berg, C.W.
Blanchard, B.
78:02G-031
Blaser, R.E.
78:021-011
Blevins, D.G.
78:021-014
Bliven, L.F.
78:06E-009
78:07B-026
Bloom, P.R.
78:07B-018
Bloomsburg, G.L.
78:02G-057
Bobovnikova, Ts.I.
78.-05B-031
Boels, 0.
78:02G-085
Bogardi, I.
78:08E-001
Boggess, S.F.
78:021-010
Bondurant, D.T.
78:02J-006
Bondurant, J.A.
78:07A-002
Borcherding, M.A.
78:05A-020
Bornstein, J.
78:076-035
Borrelli, J.
78:03F-096
Bottcher, A.B.
78:02J-019
Bottcher, A.D.
78:05B-068
Bottrall, A.F.
78:06A-013
Botzan, M.
78:03F-109
Boulton, N.S.
78:02F-012
Bouwer, H.
78:02F-027
Bovey, R.W.
78:058-023
78:05B-026
Bowles, D.S.
78:058-010
Bowman, R.A.
78:02K-014
78:078-014
Boyer, J.S.
78:021-018
Boysen, S.M.
78:08A-004
78:04A-013
286
-------
Bradford, J.M.
78:040-006
Braud, H.J.
78.-03F-089
Brazhnikova, L.Y.
78:05B-032
Brenner, S.
78-.02K-006
Bresler, E.
78:02G-004
78:026-034
78:03F-093
British Natl. Committee
78:10C-005
Broadbent, F.E.
78:021-030
78:05A-009
Brockway/ C.E.
78:03F-101
78:050-038
78:06B-002
78:07A-002
Brower, D.L.
78:02K-058
Brown, B.M.
78:02F-011
Brown, D,J.
78:020-022
Brown, D.S
78:05B-028
Brown, F.B.
78:050-035
Brown, K.W.
78:021-037
78.-05A-002
78:058-056
78:05G-039
Brown, M.J.
78:07A-002
Brown, R.J.
78:100002
Brown, R.M.
78.-02F-026
Bruce, D.A.
78:03F-091
Bruce, R.R.
78:078-025
Bruch, J.C. , Jr.
78:04A-002
Buchanan, B.A.
78:078-015
Buchta, H.G.
* 78:04A-009
Bucks, D.A.
78:03F-032
78-.Q3F-064
Bulat, J.A.
78:03F-029
Buresh, R.J.
78:02K-068
Burge, W.D.
78:058-005
Burnett, E.
78:04A-017
78:058-023
78:058-024
78:058-026
Burwell, R.E.
78:04A-012
78:058-008
Busch, J.R.
78:03F-101
78:04A-013
78:068-002
Bush, D.S.
78:05A-012
Busman, J.D.
78-.03F-118
Busscher, W.J.
78:021-004
Butcher, W.R.
78:06C-002
Cahill, T.H.
78:05G-067
Caldwell, A.C.
78:021-009
Callahan, C.A.
78:05C-007
Callies, R.E.
78:03F-098
Cameron, D.R.
78:02G-084
78:02K-071
78:058-043
Camp, C.R.
78-.04B-005
Campbell, K.L.
78:02A-004
Cannon, J.R.
78:050-035
Canode, C.L.
78:03F-024
Carder, D.R.
78:06A-014
Carlson, D.
78:050-073
Carson, P.L,
78:021-005
Carter, C.E.
78:046-005
Carter, D.L.
78:020-039
Cassel, O.K.
78:021-006
78:03F-001
78:05B-019
Cauchois, S.
78:06B-021
Cavallaro, N.
78.02K-034
Chandra, S.
78:02J-001
Chang, C.
78:058-043
Chaudhry, F.H.
78:03F-030
Chauhan, H.S.
78:02F-016
Cheng, H.H.
78:058-029
Cherkhanov, Yu.P.
78:058-031
Cherry, J.A.
78:02F-026
Chesness, J.L.
78:03F-061
Chichester, F.W.
78.-02K-009
78:058-025
Chien, S-H.
78:02K-066
Campbell, G.S.
78:02G-020
Chiu, C.L.
78:088-011
287
-------
Chiu, C-L.
78:02E-005
Choi, E.C.C.
78:02F-014
Chorley, D.W.
78:02F-022
Christenson, D.R.
78:021-043
Chu, S.T.
78:02G-052
Ciravolo, T.G.
78:021-024
Clapp, R.B.
78:02G-073
Clark, R.T.
78:03F-096
Clarke, J.M.
78:021-038
Clarke, R.T.
78:02E-001
Clemmens, A.J.
78:03F-064
78:076-011
78:076-027
Clift, T.R.
78:02E-010
Cluff, C.B.
78:08G-001
Cohen, B.
78:05G-067
Cohon, J.L.
78.-04A-004
Cole, C.V.
78:02K-014
Conklin, L.R.
78:068-002
Conner, B.J.
78:058-006
Contractor, D.N.
78:02J-024
Cook, F.D.
78:03F-029
Cook, K.A.
78:078-009
Coote, D.R.
78:05A-016
78:056-046
Cotnoir, L.J.
78:056-011
Couvillon, G.A.
78:03F-061
COX, C.M.
Cox, F.R.
78:058-041
78:02K-051
Cronan, C. S.
78:02G-005
Crops & Soils Magazine
78:03F-050
Currier, J.B.
78:058-065
Curtis, L.M.
78:03F-078
Cushman, J.
78:02G-048
D'Arge, R.C.
78:056-035
Dagan, G.
78:02F-017
78:02G-018
Dale, R.F.
78:02A-001
78:02G-038
Dalton, F.N.
78:021-013
Dancette, C.
78:036-001
Dasberg, S.
78:026-050
78:056-002
Davey, B.G.
78:02K-063
Davidson, J.M.
78.-03F-013
78:056-018
78:056-027
Davies, R.I.
78:076-019
Davis, C.L.
78:026-058
Davis, H.H.
78:056-072
Davis, M.J.
78:056-063
Davis, S.S.
78:02J-005
Day, A.D.
78:03F-002
De Datta, S.K.
78:02K-043
De Kimpe, C.R.
78:02K-050
De, S.K.
78:02J-001
Dean, J.D.
78:056-064
Decoursey, D.6.
78:02J-012
Dedrick, A.R.
78:03F-034
78:03F-128
78:03F-130
DeHaan, R.
78:056-046
Dehan, K.
78:03C-005
DeJong, R.
78:056-043
Delaney, R.H.
78:03F-096
DeLucia, R.
78:058-009
Demchenko, A.S.
78:056-032
DeMeterio, J.L.
78:058-040
DeMichele, D.
78:056-039
Dempster, T.H.
78:066-014
DeRoo, H.C.
78:02Q-019
DeSmedt, F.
78:026-006
78:026-015
DeTar, W.R.
78:03F-059
Deuel, L.
78:056-039
288
-------
Deuel, L.E.
78:021-037
78J05B-056
Develice, R.L.
78:07B-015
Devitt, D.
78:02G-046
Dideriksen, R.I.
78:02J-021
Dirksen, C.
78j02G-011
78:020-016
78:03F-110
78:05G-044
Diskin, M.H.
78:02A-005
Dixon, J.B.
7S:02K-025
Doering, E.J.
78:03F-125
Doll, E.G.
78:021-043
Dominguez, J.
78:021-036
Doner, H.E.
78.-02K-064
Doney, D.L.
78:03F-028
Donigian, A.S.
78:056-065
78:05G-072
Donnan, W.W.
78:05G-025
Dooley, H.L.
78:021-022
Dooris, P.M.
78:021-027
Douglas, E.
78:020-024
Douglas, L.A.
78:078-003
Drablos, c.J.W.
78:03F-124
78:040-001
Draperi D.W.
78:05A-016
Duble, R.L.
78:05A-002
Duckstein, L.
78:08E-001
Dudek, D.J.
78:068-001
Duich, J.M.
Duke, H.
78:03F-003
78:021-041
Duke, H.R.
78sQ2F-020
78;03F-069
78:03F-116
78:03F-117
78:043-002
78:05G-077
Duseja, D.R.
78:02K-016
Dusek, D.A.
78:021-042
Duxbury, J.M.
78:02K-067
78:Q5B-046
Dworsky, R.F.
78:05G-050
Eagleson, P.s.
.78:02A-007
78:02A-008
78:02A-009
78:026-001
78:020-005
78:02G-068
78:026-074
Eastburn, R.P.
78t02D-003
78:058-037
Edling, R.J.
78:03F-117
Edwards, A.L.
78:02F-006
Edwards, W.M.
78:05B-006
Edworthy, K.J.
78:048-010
Eggert, K.G.
78:06A-015
Eisenhauer, D.E.
78:03F-083
El-Ghansry, W.M.
78:020-080
Elliott, L.F.
78:05G-076
Ellis, J.W.
78:078-025
Elprince, A.M.
78:058-042
Elrick, D.E.
78:02G-012
England, M.
78:03F-060
Enkiri, N.K.
78:05B-005
Erbach, D.C.
78:03F-108
Erickson, C.J.
78:021-016
Erie, L,J.
78:03F-034
78:03F-128
78:03F-130
Estes, J.E.
78:060-001
Ethridge, W.J.
78:021-001
Evans, D.W.
78:02G-026
Evans, R.G.
78:058-022
78:05G-009
78:05G-011
Fangmeier, D.D.
78:02G-083
78:03F-099
78:03F-118
Fanning, D.S.
78:021-032
Federer, C.A.
78:02A-011
Fenemor, A.D.
78:08G-002
Fenster, c.R.
78:03F-113
Ferguson, J.A.
78:02K-065
Ffolliott, P.P.
78:06A-014
Firestone, M.K.
78:02K-029
289
-------
Fischbach, P.
78:03F-049
Fischbach, P.E.
78:021-040
78:03F-033
78:03F-083
78.-03F-086
Fisher, H.D.
78:03F-115
Fitzsimmons, D.W.
78:04A-013
78:066-002
Fixen, P.E.
78:021-005
Flaig, W.
78:07B-003
Flores, E.Z.
78:02F-009
78:04A-001
Focht, D.D.
78:02G-050
78:02K-057
78:07B-023
Fok, Y-S.
78:030-001
Follett, R.F.
78:03F-125
Follett, R.H.
78:03F-113
Ford, H.W.
78:03F-090
Foster, G.R.
78:02J-005
Fox, R.H.
78:07B-013
78:076-024
Frank, J.F.
78:050-061
Frenkel, H.
78:020-010
78:020-045
78:020-046
78:030003
78:050-036
Fried, M.
78:021-030
Frind, E.G.
78:02F-022
78:04B-011
Frink, C.R.
78:020-019
Fritton, D.D.
78:021-004
78:06D-002
Fritz, P.
78:02F-026
Frobel, R.K.
78:080-001
Frota, J.N.E.
78:021-028
78:021-029
Fryrear, D.W.
78:04A-010
Fuchs, M.
78:020-020
78:03F-007
Gabriels, D.
78:02J-027
Oakstatter, J.H.
78:050007
Galinato, G.D.
78:03F-101
Gamble, J.
78:03F-088
Gaponyuk, E.I.
78:050002
Gardner, B.D.
78:05G-022
Gardner, D.M.
78:06E-002
Gardner, W.R.
78:02G-009
78:02G-062
78:021-013
Garner, B.J.
78:048-006
Gast, R.G.
78:05A-004
Gelhar, L.W.
78:02F-007
78:02F-023
78:04A-001
78:058-039
Gembrell, R.P.
78:02K-048
Gerard, C.J.
78:030002
Gerdts, M.
78:03F-080
Gerrish, J.B.
78:05A-018
Gharaaty-Sani, R.
78:06A-005
Ghate, S.R.
78:02G-081
Ghildyal, B.P.
78:020-076
Gibbs, K.C.
78:060002
Gifford, G.F.
78:04A-006
78:05B-012
Gilbert, R.G.
78:03F-032
78:058-047
Gilley, J.R.
78:03F-049
78:03F-072
Gilliam, J.W.
78:020-050
78:02K-048
78:05G-018
78:050-034
78:050-074
Gilmour, C.M.
78:050006
Gilmour, J.T.
78:02K-065
Gilmour, R.
78:05G-060
Ginberg, P.
78:068-019
Ginn, L.H.
78:078-001
Giordano, P.M.
78:03F-025
Giraldez, J.V.
78:020-047
Giskin, M.
78:02G-030
Gleason, V.E.
78:06E-007
Goertzen, J.O.
78:020-010
78:05G-036
290
-------
Goldberg, D.
78:03F-007
Golovleva, L.A.
78:02K-042
Gordos, J.D.
78:048-009
Gormly, J.R.
78:05A-010
Gosling, R.
78:03F-084
Gould, W.D.
78:03F-029
Gove, S.K.
78:06E-002
Graham, E.R.
78:07B-009
Grant, M.C.
78:078-028
Grass, L.B.
78:02K-052
Green, D.B.
78:058-007
Green, P.
78:02J-018
Greer, J.D.
78:05G-043
Grenney, W.J.
78:058-010
Greydanus, H.W.
78:043-004
Griffin, S.G.
78:03F-058
Griffis, C.L.
78:02K-065
Griffis, W.
78:021-022
Groszyk, W.S.
78:06E-010
Guitjens, J.C.
78:058-002
Guntermann, K.L.
78:06E-002
Gur, Y.
78:02K-008
Guthrie, T.F.
78:02K-067
Gutiahr, A.L.
78:02F-007
78:02F-023
78:04A-001
Haan, C.T.
Hadas, A.
78:02A-010
78:02J-009
78:02K-004
78:030-003
Hagan, R.M.
78:03F-079
Hagedorn, C.
78:058-004
78:058-052
Hageman, L.
78:02K-059
Hagin, J.
78:02K-005
Haith, D.A.
78:05G-071
78:068-017
Halderman, A.D.
78:040-007
Hall, A.E.
78:038-001
Hall, J.K.
Ham, G.E.
78:05A-003
78:021-009
Hamad, S.N.
78:040-008
Hamilton, A.
78:06E-014
Hamilton, M.
78:050-001
Hammond, J.
78:03F-107
Hammond, L.C.
78:03F-008
Hampieke, U.
78:06G-002
Hancock, C.V.
78:05G-062
Gureghian, A.B.
78:02F-019
Hankin, L.
78:078-034
Hanks, R.J.
78:021-025
78:03F-056
Hann, R.W., Jr.
78:06A-008
Hannoura, A.A.
78:08B-012
Hansen, D.T.
78:058-004
Hanson, C.L.
78:021-016
Hanson, E.G.
78:03F-063
Hanson, R.E.
78:03F-071
Harmon, W.C.
78:02J-025
Harpaz, A.
78:05G-002
Harper, W.C.
78:05G-069
Harrington, J.
78:058-009
Harrison, D.S.
78:03F-065
Hartwig, N.L.
78:05A-003
Hauck, R.D.
78-.03F-018
Haun, J.R.
78:021-035
Hauser, V.L.
78:04A-018
Hawkins, R.H.
78:04A-006
78:05B-038
Hayes, J.C.
78:02J-022
Hayes, R.O.
78:06G-001
Hayhoe, H.N.
78:02G-001
78:02G-027
Heady, E.O.
78:04A-003
78:05G-003
78:068-010
78:06E-021
291
-------
Heaney, J.P.
78:06A-016
Heatherly, L.G.
78:078-001
Hebb, E.A.
78:056-035
Hedstrom, W.E.
78:03F-096
Heermann, D.
78:021-041
Heermann/ D.F.
78:03F-069
78:03F-104
78:05G-077
Helvey, J.D.
78:05B-049
Helweg, O.J.
78:05G-016
Hendrickson, L.L.
78:03F-004
78:03F-005
78:078-002
Henriksen, A.
78:02K-044
Henry, C.
78:03F-052
78:03F-114
78:07A-001
Hermsmeier, L.F.
78:030-006
Herrera, I.
78:02F-009
Hesseltine, B.B.
78:058-011
Hiatt, A.J.
78:021-014
Hidlebaugh, A.R.
78:02J-021
Highsmith, R.M.
78:06A-007
Hiler, E.A.
78:048-008
Hill, J., IV
78:06A-002
Hill, R.W.
Hillel, D.
78:02G-021
Hills, F.J.
78:021-030
Hipel, K.W.
78:02E-004
78:02E-008
78:02E-009
Hira, G.S.
78:02K-036
Hoeft, R.G.
78:02K-017
78:02K-018
Hoffman, D.L.
78:02K-061
Hoffman, G.J.
78.021-015
78:056-044
Hogg, T.J.
78:021-033
78:02K-055
Holburt, M.B.
78:06E-006
Holmes, E.E.
78:02K-016
Hoover, J.R.
78:020-058
Hornberger, G.M.
78:02G-073
Horner, G.L.
78:068-001
Horney, L.F.
78:06E-009
Horta, M.
78:021-036
Hossner, L.R.
78:02K-047
78:05C-001
Houck, M.H.
78:04A-004
Howald, R.A.
78:02K-059
Howell, T.A.
78:088-006
78:06A-006
Howitt, R.
Hoyt, G.D.
78:058-003
Hliber, M.J.
78:02G-011
78:020-016
Huggins, L.F.
78:02J-005
78:02J-019
Hughes, T.C.
78:088-010
Humenik, F.J.
78:06E-004
78:078-026
Humpherys, A.
78:03F-053
Humpherys, A.S.
78:03F-115
Hunt, B.
78:058-017
Huntley, D.
78:02F-021
Kurd, M.
78:100006
Hurst, R.L.
78:03F-028
Huszar, P.C.
78:05G-012
78:05G-013
78:05G-014
78:05G-015
78:050-033
ICID Committee
78:03F-042
Idso, S.B.
Ikan, R.
78:020-006
78:03F-112
78:02K-006
78:066-021
Imberger, J.
78:02H-001
Ingvalson, R.D.
78:05G-044
Irrigation Age
78:03F-036
78:03F-037
78:03F-038
78:03F-046
78:03F-051
78:048-0.14
292
-------
Irrigation Journal
78:03F-043
78:03F-044
Ishikawa, T.
78:02J-013
Isu, E.O.
78:02E-005
78:088-011
Ivarson, K.C.
78:02K-071
Ivey, G.
78:02H-001
Jackson, E.B.
78:03F-002
Jackson, L.G.
78:04A-009
Jackson, R.D.
78:03F-112
Jackson, T.L.
78:03F-012
Jacobs, J.J.
78:03F-096
James, D.W.
78:03F-028
James, W.P.
78:020-004
Jarrett, A.R.
78:02G-058
78:02G-059
78:03F-102
Jenkins, D.A.
78:02K-045
78:078-019
Jensen, J.R.
78:060-001
Jensen, H.E.
78:020-007
78:020-008
Jensen, P.A.
78:063-020
Jeppson, R.W.
78:083-010
Jessup, R.E.
78:02G-013
Jimenez, R.A.
78:080-001
Jobson, H.E.
78:02E-003
Johannessen, M
78:02K-044
Johnson, A.T.
, 78:078-032
Johnson, C.W.
78:02J-008
Johnson, D.
78:068-009
Johnson, H.P.
78:05A-020
Johnson, J.S.
78:05G-049
Johnson, J.T.
78:021-017
Johnson, R.R.
78:021-018
Johnston, W.R.
78:056-023
Jones, J.P.
78:058-037
78:056-059
Joung, H.M.
78:058-002
Jurgens, S.K.
.78:021-018
Jurinak, J.J.
78:02K-024
78:07A-003
Jury, H.A.
78:026-045
78:026-046
78:026-065
78:030003
78:058-021
Kafkafi, U.
78:021-026
78:02K-004
78:02K-037
Kalbasi, M.
78:02K-010
78:02K-013
Kamprath, E.J.
78:02K-069
Kanwar, R.S.
78:02F-016
Karickhoff, S.W.
78:058-028
Karimian, N.
78:02K-051
Karmeli, D.
78:03F-020
78:03F-054
78:03F-126
Karr, J.R.
78:06E-002
Kaufman, D.D.
78:078-016
Kaufmann, M.R.
78:021-015
Kaushik, N.K.
78:05B-064
Kay, B.D.
78:02C-001
Kearney, P.C.
78:078-016
Keasler, L.C.
78:05G-055
Keefer, T.N.
78:02E-003
Keener, M.R.
78:021-037
Keeney, D.R.
78:03F-004
78:03F-005
78:078-002
Keisling, T.C.
78:02G-013
78:02K-041
Keller, J.
78:03F-127
78:088-005
Kelly, G.D.
78:02J-010
Kelso, G.L.
78:03F-102
Kennedy, H.G.
78:021-007
Kepler, K.
78:056-073
Ketcheson, J.W.
78:02F-002
Khaleel, R.
78:05A-017
Khan, N.A.
Khan, P.
78.-02K-003
78:02K-003
293
-------
Khanjani, M.J.
78:020-057
Khanna, P.K.
78:02K-015
Khera, R.P.
78:09A-001
Kibler, D.F.
78:060-002
Kikkawa, H.
78:02J-013
Kincaid, D.C.
78:03F-116
King, L.G.
78:06A-004
78:06A-005
Kinnell, P.I.A.
78:02J-018
Kirkham, D.
78:02F-001
78:02G-048
78:05B-062
Kirkham, M.B.
78:021-031
Kissel, D.E.
78:02K-009
78:02K-020
Klameth, L.C.
78:02K-028
Kleinraan, A.P.
78:05G-035
78:05G-075
Klepper, B.
78:078-005
Klepper, R.
78:058-001
Kling, G.F.
78:058-052
Knight, J.H.
78:02G-012
Knight, W.A.
78:050-062
Knisel, W.G., Jr.
78:02E-002
Kobzev, V.A.
78:050002
Koehler, F.A.
78:06E-009
78:078-026
Koeppe, D.E.
78:021-010
Kohberger, R.C.
78:05A-006
Lai, S-H.
78:02K-024
Kohl, D.H.
Kohn, B.
78:02K-066
78:04D-002
Konwinski, G.R.
78:02J-028
Korcak, R.F.
78:021-032
Korotova, L.G.
78:058-032
Kort, R.
78:078-032
Kowalenko, C.G.
78:02K-071
Kramer, L.A.
78.-04A-012
Krishnaraurthi, N.
78:02G-049
Kroutil, W.F.
78:03F-048
Kruh, G.
78:02K-005
Kruse, E.G.
78:050-028
Kuepper, G.
78:068-009
Kuhaida, A.J.
78:078-033
Kuhner, J.
78:068-019
Kuiper, L.K.
78:02F-024
Laag, A.E.
78:03F-010
Labeda, D.P.
78:058-054
Laflen, J.M.
78:02J-006
78:050-029
Lagerwerff, J.V.
78:02K-058
Lake, J.E.
Lai, P.
78:05G-048
78:03F-022
Lambert, J.R.
78:021-020
Landa, E.R.
78:02K-033
78:05A-022
Landwehr, J.M.
78:05A-015
Langdale, G.W.
78:040-003
Langford, K.J.
78:02E-010
Langhetee, E.J.
78:04B-013
Langton, D.N., III
78:058-011
Lapina, N.F.
78:058-033
Larsen, R.
78:04A-016
78:08A-001
Larson, C.L.
78:04A-015
Larson, F.R.
78:06A-014
Lash, 0.
78:02A-011
Laverdiere, M.R.
78.-02K-050
Law, A.G.
78:03F-024
Layton, D.W.
78:048-001
Leggett, J.E.
78:021-014
Lembke, W.D.
78:03F-124
Leonard, R.A.
78:040-003
Lesczynski, D.B.
78:078-002
294
-------
Letey, J.
78:03F-OZ5
Loewen-Rudgers, L.A.
78:02K-010
Lettenmaier, D.P.
78:05A-007
Leung, S.
Levin, I.
Levy, Y.
78:068-021
78:02G-030
78:05G-002
78:03C-004
Lewen-Rudgers, L.A.
78:02K-013
Lewis, G.C.
78:04A-013
Lewis, W.M.
78:076-028
Li, R.M.
78:06A-015
78:083-001
Liang, C.N.
78:05A-005
Libby, L.W.
78:06E-014
Liegel, E.A.
78:03F-005
Liesemeyer, W.W.
78:04A-009
Liggett, J.A.
78:02F-008
Lilly, J.P.
78:02K-019
Lin, S.H.
78.-02G-061
Lindsay, W.L.
78:02K-031
78:073-012
Little, W.C.
78:02J-011
Liu, P.L.-P.
78:02F-008
Loch, J.P.G.
78:020-001
Loehr, R.C.
78;05G-071
Log^n, T.J.
Loh, A.
78:02K-032
78:058-003
78:058-007
78:058-026
Lomen, D.O.
78:020-017
78:020-041
Long, R.B.
78:068-002
Longenbaugh, R.A.
78:020-049
Longley, T.S.
78:02J-015
Loudon, T.L.
78:05A-018
Lovell, A.D.
78:078-025
Lovely, W.G.
78:03F-108
Lowe, R.H.
78:021-014
Ludwick, A.E.
78:03F-057
Lund, L.J.
78:02G-050
78:03F-010
78:078-023
Maas, E.V.
78:050-044
MacDonald, E.M.
78:050-046
MacKenzie, A.J.
78:02K-052
MacMillan, J.R.
78:02F-007
78:02F-023
Madison, F.W.
78:05A-019
Magdoff, F.R.
78:03F-023
Mahannah, C.N.
78:058-002
Maji, C.C.
78:04A-003
Malekuti, A.
78:058-012
Maloney, R.C.
78:058-065
Manges, H.L.
78:03F-123
Manley, R.E.
78:02A-002
Mansell, R.S.
78:03F-008
Mao, L-T.
78:03F-123
Marian, M.B.
78:03F-068
Marsee, C.W.
78:06C-001
Martel, Y.A.
78:02K-050
Martin, C.S.
78:05G-071
Martin, D.
78:03F-060
Martin, D.F.
78:021-027
Masarik, D.
78:058-055
Matlin, R.W.
78:03F-086
McBean, E.
78:056-009
McBride, M.B.
78:02K-034
78:07B-018
McCallister, D.L.
78:02K-032
McColl, J.G.
78:05A-012
McCorquodale, J.A.
78.08B-012
McCoy, E.L.
78:058-052
McDowell, L.L.
78:02J-025
78:050-043
295
-------
McElwee, C.D.
78:02A-003
McFee, W.W.
78:058-055
McGrann, J.M.
78:02J-020
78:063-012
McGregor, K.C.
78:05G-043
McGuirk, M.
78:078-035
McKusick, R.B.
78:068-001
McKeyes, E.
78:02G-024
McLean, E.O.
78:058-003
McLeod, A.I.
78:02E-004
78:02E-008
78:02E-009
McNeal, B.L.
78:03F-016
McWhorter, D.B.
78:02F-020
78:048-002
McWilliams, E.L.
78:05C-001
Meek, B.D.
78:02K-052
Mein, R.G.
78:02F-011
Menzel, R.G.
78:05G-008
78:05G-037
Merculiev, O.
78:03F-10?
Merkle, M.G.
78:058-023
Merriam, J.L.
78:03F-100
Merrill, S.D.
78:03F-110
Mevorach, J.
78:088-003
Meyer, J.
Meyer, L.D.
78:02J-025
Meyer, R.E.
78:058-023
78:058-026
Michener, D.W.
78:048-009
Mikkelsen, D.S.
78:02K-043
Milberg, R.P.
78:02K-058
Miles, N.M.
78:02K-073
Miller, D.E.
78:078-021
Miller, J.B.
78:058-047
Miller, M.R.
78:02J-007
Miller, P.J.
78:056-016
Miller, R.D.
78:02G-034
Miller, R.J.
78:03F-010
Miller, T.K.
78:068-003
Miller, W.W.
78:058-002
Mills, W.C.
78:02E-002
Miner, G.S.
78:02K-019
Minzoni, A.
78.-02F-009
Miranowski, J.A.
78:068-010
Mitchell, B.D.
78:02J-026
Mitchell, W.H.
78:058-011
Miyamoto, S.
78:056-001
Moberg, E.L.
78:03F-003
Modi, M.S.
78:03F-022
Moldenhauer, W.C.
78:02J-027
Monke, E.J.
78:02J-019
78:058-068
Moore, I.e.
78:05A-019
Moore, I.D.
78:04A-015
Moore, R.J.
78:02E-001
Morehart, A.L.
78:058-011
Morel-Seytoux, H.J.
78:02G-063
78:026-072
Morgan, R.M.
78:03F-103
Morozova, G.K.
78:058-031
Morris, G.R.
78:086-001
Morrow, C.T.
78:02G-059
Morse, W.L.
78:020-001
Mortvedt, J.J.
78:020-032
78:02G-033
78:03F-025
Mosier, A.R.
78:05C-003
Motz, L.H.
78:02F-018
Mousavi, S.-F.
78:02F-001
Mualem, Y,
78:02F-010
78:026-018
78:020-042
78:026-063
Mubarak, A.
78:02K-059
78:068-012
296
-------
Muckleston, K.W.
78:06A-007
Mueller, R.T.
78:02K-072
Mulkey, L.A.
78:05G-064
Muller, R.N.
78:02K-011
78:040-002
Munson, B.B.
78:078-033
Murabayashi, E.T.
78:030-001
Murdoch, L.W.
78:03F-027
Murphy, L.S.
78:05G-007
Murphy, T.A.
78:06E-011
Musick, J.T.
78:021-042
Mussalli, Y.G.
78:088-007
Myers, J.M.
78:03F-065
Myhre, D.L.
78:02K-070
Nakano, Y.
78:02F-004
Nakayama, F.5.
78:03F-032
78:03F-064
Nalluri, C.
78:088-008
Narasimhan, T.N.
78:02F-006
78:048-012
78:06A-009
Nash, K.G.
78:05A-010
Nash, R.G.
78:078-016
Nebgen, J.W.
78:05G-063
Nelson, D.W.
78:058-068
Nelson, M.C.
78:050-058
Nelson, R.E.
78:02K-028
Nelson, R.W.
78:056-057
78:058-058
78:058-059
78:058-060
Nelson, W.L.
78:02A-001
Nelson, W.W.
78:05A-004
Nettleton, W.D.
78:02K-028
Neuman, S.P.
78:048-012
New, L.L.
78:026-025
Nicholaichuk, W.
78:058-044
Nicholls, K.H.
78:058-041
Nicholson, H.P.
78:06A-003
Nielsen, N.E.
78:021-012
Nielsen, R.L.
78:06G-001
Nishita, H.
78:050-001
Nissenbaum, A.
78:02K-006
Nofziger, D.L.
78:02G-075
Nordin, C.F.
78:088-013
Norvell, W.A.
78:078-012
Novais, R.
78:02K-069
Obsemea, W.N.
78:02K-043
Olness, A.E.
78:050-037
Olosky, C.J.
78:048-009
Olsen, S.R.
78:073-014
Olson, B.R., Jr.
78:03F-045
Olson, R.A.
78:03F-019
On-Farm Irri. Committee
78:068-005
Onesti, L.J.
78:068-003
Onstad, C.A.
78:02E-011
Oostermeyer, J.S.
78:03F-067
Ortiz, N.V.
78:02F-020
78:048-002
Osteen, C.
78:05G-058
Oster, J.D.
78:050-044
Ou, L-T.
78:058-027
Overcash, M.R.
78:05A-017
78:078-026
Paetzold, R.F.
78:02G-040
78:02K-062
Paily, P.P.
78:058-015
Pall, R.
78:020-059
Panu, U.S.
78:02E-007
Papendick, R.
78:02G-020
Parfitt, R.L.
78:02K-030
Parlange, J.-Y.
78:020-008
Parlange, J.Y.
78:02G-019
78:020-055
297
-------
Parsons, B.L.
78:02J-007
Partenheimer, E.J.
78:06B-011
Paterson, E.
78:02J-026
Patrick, W.H.
78:02K-068
Patrick, W.H., Jr.
78:02G-035
78:02G-036
78:02G-051
78:02K-001
78:02K-027
Patt, R.O.
78:02F-005
Patterson, C.
78:03F-074
Payne, M.L.
78:03F-116
78:03F-117
Payne, W.R.
78:05A-020
Penkava, F.F.
78:03F-070
Perkins, H.F.
78:078-036
Peverly, J.H.
78:058-046
Pfeiffer, G.H.
78:05B-006
Philip, J.R.
78:02G-012
78:02G-043
Phillips, A.L.
78:06A-006
Phillips, D.A.
78:078-006
Phillips, D.W.
78:020-002
Phillips, K.J.
78:058-039
Phillips, N.A.
78:05A-021
Phillips, R.E.
78:02G-035
78:026-036
78:021-014
78:02G-066
78:021-019
Piekielek, W.P.
78:078-013
78:078-024
Pierson, R.W.
78:05G-067
Piest, R.F.
78:02J-011
78:040-006
Pietz, R.I.
78:058-055
Pitts, W.T.
78:05G-073
Plate, H.
78:05G-070
Pomareda, C.-
78:03F-009
Ponce, S.L.
78:058-038
Ponce, V.M.
78:088-001
Popov, E.E.
78:058-033
Poulovassilis, A.
78:02G-080
Power, J.F.
78:021-016
Prasad, K.G.
78:078-036
Prather, R.J.
78:05G-036
Pratt, P.F.
78:03F-016
78:050-042
78:10A-001
Price, J.
78:056-039
Price, J.D.
78:058-024
78:058-056
Pringle, J.C.
78:058-048
Quisenberry, V.L.
78:02G-066
Qureshi, R.H.
78:02K-045
78:078-019
Raats, P.A.C.
78:02G-077
78:02G-078
78:03F-110
Rachinskii, V.V.
78:02G-056
Racz, G.J.
78:02K-010
78:02K-013
Radosevich, G.E.
78:056-012
78:05G-013
78:05G-014
78:050-015
78:06E-001
Rahe, T.M.
78:058-052
Rahman, M.
78:02H-002
Raines, R.W.
78:058-048
Rajagopal, R.
78:05A-001
Ramig, R.E.
78:021-008
Ramirez, J.M.
78:021-006
Ramsey, M.K.
78:026-083
Randall, G.W.
78:05A-004
Rankin, J.M.
78:078-030
Rao, P.S.C.
78:026-013
78:03F-013
78:058-018
Rasmussen, V.P.
78:021-025
Rasmussen, W.O.
78:06A-014
Rasmussen, W.W.
78:078-021
Rastogi, A.K.
78:058-061
298
-------
Rauschkolb, R.S.
78:05G-005
Ravelo, C.J.
78:04B-008
Ravina, I.
78:02K-008
Rawls, W.J.
78:02E-011
Read, D.W.L.
78:053-044
Reardon, E.J.
78:02F-026
Rector, M.R.
78:050-025
Reddell, D.L.
78:02G-060
78:04B-008
78:058-067
Reddy, G.G.
78:03F-022
Reddy, G.Y.
78:053-003
Reddy, K.R.
Reed, W.
Reeve, R.
78:026-035
78:02G-036
78:020-051
78:02K-001
78:05A-017
78:06B-021
78:073-008
Reeve, R.C.
78:08A-002
Reginato, R.J.
78:03F-112
Reichman, G.A.
78:03F-125
Reicosky, D.C.
78:021-020
Reizes, J.A.
78:02J-017
Rendon-Herrero, 0.
78:02J-004
Reneau, D.R.
78:068-015
Replogle, J.A.
78:03F-034
78:073-011
78:078-027
Reus s, J.O.
78:021-022
78:02K-023
Rhoades, E.D.
78:05G-037
Rhoades, J.D.
78:05G-036
Rhoads, F.M.
78:03F-008
Rice, J.M.
78:06E-013
Rice, R.C.
78:02F-027
Richardson, C.
78:053-023
78:053-026
Richardson, C.W.
78:04A-017
78:053-024
Rickman, R.W.
78:021-008
78:073-005
Riggle, F.R.
78:073-017
Richtmire, C.T.
78:02K-056
Ring, L.
78:03F-104
Ripken, J.F.
78:088-009
Ritter, W.F.
78:020-003
78:053-037
78:063-020
Rivers, E.D.
78:02G-079
Roades, J.D.
78:02G-010
Robbins, C.W.
78:02G-039
78:050-038
Robertson, W.K.
78:021-017
Robillard, P.O.
78:05G-060
Robinson, A.R.
78:02J-011
Robinson, J.B.
78:05A-016
78:053-064
Robinson, S.C.
78:03F-085
Robledo, E.
78:021-036
Rodarte, L.
78:02F-003
Rodger, N.
78:03F-039
Rodi, W.
78:05B-061
Rogers, P.
78:06A-010
Rolston, D.E.
78:02K-061
78:03F-017
78.-05A-009
Rosendahl, P.C.
78:050-030
Ross, B.B.
Ross, R.
78:02J-024
78:08C-001
Rossman, L.A.
78:050-031
Rothwell, D.F.
78:053-027
Rouse, J.W.
78:020-004
Routson, R.C.
78:02G-022
Rumburg, C.B.
78:03F-057
Rupar, B.
78:03F-076
Russell, W.J.
78:073-001
Russo, D.
78:02G-034
299
-------
Ryan, J.
78:02K-003
Ryan, M.E.
78:05G-043
Ryden, J.C.
78:03P-010
78:078-023
Sabey, M.B.
78:05G-033
Sabol, G.V.
78:086-013
Sagar, B.
Sain, P.
78:02F-013
78:02F-025
78:05B-064
Saini, B.C.
78:02G-076
Salazar, L.J.
78:03F-020
Sammis, T.W.
78:03F-026
78:03F-063
San Valentin, G.O.
78:021-017
Sanders/ T.G.
78:05A-008
Sanghi, A.K.
78:068-009
Sawhney, B.L.
78:078-034
78:06A-007
Sayegh, A.H.
78:02K-003
Sayler, G.S.
78:050006
Sayre, W.W.
78:058-015
Scavia, D.
78:05A-006
Schmugge, T.
78:02G-031
Schneider, R.R.
78.-05A-019
78:05G-004
Schoenhofer, R.F.
78:05G-062
Scholl, D.G.
78:026-071
Schuman, G.E.
78:058-008
78:05G-076
Schwab, G.O.
78:04B-009
78:086-002
Scott, H.D.
78:02G-040
78:02K-062
Seginer, I.
78:03F-092
Seitz, W.D,
78:056-058
78:06E-002
Sekhon, G.S.
78:056-021
Selim, H.M.
78:026-086
78:058-018
Sepaskhah, A.R.
78:026-029
Sethunathan, N.
78:02K-049
78:02K-053
Shalhevet, J.
78:021-003
78:030-004
Shanholtz, V.O.
78:02J-024
Shannon, M.C.
78:03C-001
Sharma, T.C.
78:026-082
Sharon, S.
78:02K-005
Sharp, B.M.H.
78:06E-015
Sharpley, A.N.
78:05A-011
Shaw, R.H.
78:03F-021
Shearer, G.
78:02K-066
Shearer, M.N.
78:03F-081
Sheffield, L.F.
78:068-007
Shen, H.T.
78:058-013
Sherman, B.
78:04A-007
Shimshi, D.
78:021-026
Shipp, R.F.
78:026-079
Shirk, K.S.
78:02K-065
Shuman, L.M.
78:02G-037
Siemer, E.G.
78:03F-057
Simons, D.B.
78:06A-015
78:088-001
Simonson, G.H.
78:058-004
Simpson, E.S.
78:02A-005
Simpson, G.M.
78:021-038
Sims, J.L.
78:02K-027
Sinai, G.
78:02A-004
Singer, A.
7«:02K-007
Singer, M.J.
78:040-004
Singh, B.
78:056-021
Shayan, A.
78:02K-063
Singh, N.T.
78:02K-036
Singh, P.N.
78:086-003
Singh, S.S.
78:02K-073
300
-------
Singh, T.
78:03F-006
Singh, V.P.
78:04A-007
Sinitsyna, 2.A.
78:05B-031
Sisneros, D.A.
78:05B-048
Sivakumar, M.V.K.
78:03F-021
Siverts, L.E.
78:053-065
Skaggs, R.W.
78:02F-028
78:02G-081
78:04A-005
78:048-007
78:048-008
78:048-009
78;05G-018
78:05G-034
78:056-074
Skjemstad, J.O.
78:078-008
Skogerboe, G.V.
78:03F-031
78:058-022
78:05G-009
78:05G-011
78:05G-012
78:05G-013
78:050-014
78:05G-015
78.'10C-001
Skryabin, G.K.
78:02K-042
Slack, D.C.
78:078-017
Sloss, J.M.
78:04A-OQ2
Smajstrla, A.G.
78.-02G-060
Smart, R.St.C.
78:02K-030
Smeck, N.E.
78:02J-003
78:058-007
Smika, D.E.
78:05G-045
78:050-077
Smiles, D.E.
78:026-007
78:020-012
78:020-043
Smith, C.N.
78:040-003
Smith, D.V.
78:068-019
Smith, J.H.
78:05B-047
Smith, J.P.
78:02J-008
Smith, M.S.
78:02K-029
Smith, R.E.
78:020-055
Smith, R.L.
78:04C-001
Smith, S.J.
78:02K-009
78:02K-020
78:02K-075
78:058-025
78:05G-037
Smith/ S.W.
78:05G-009
78:10C-001
Sneed, R.E.
78:03F-075
Snyder, W.M.
78:02E-002
Sochtig, H.
78:078-003
Sokolov, M.S.
78:058-034
Solomon, K.
7a:03F-087
78:03F-105
78:03F-127
78:088-004
Sommers, L.E.
78t05B-068
Sotres, M.O.
78:058-062
Spalding, R.F.
78:05A-010
Spomer, R.G.
78:040-006
Sposito, G.
78:020-047
78:020-053
78:020-054
Sprugel, D.G.
78:040-001
Sprugel, D.S.
78:040-002
Stammers, W.
78:058-064
Stanford, G.
78:02K-074
7S.-02K-075
Starr, J.L.
78:02G-008
78.-02G-019
steen, A.J,
78:050-001
Steenhuis/ T.S.
78:058-036
Stegman, E.G.
78:021-034
Steinbach, G.E.
78:03F-101
Steinhardt, R.
78:078-022
Stewart, C.E.
78:050-022
Stewart, J.W.B.
78:021-033
78:02K-055
Stierna, J.H.
78:068-014
Stolzy, L.H.
78:020-045
78:02G-046
78:02K-057
78:03F-015
Stott, D.A.
78:048-010
Stout, W.L.
78:078-004
Strelkoff, T.
78:03F-099
Streltsova, T.D.
78:02F-012
Stringham, G.E.
78:04D-008
301
-------
Stuff, R.G.
78:020-038
Stumpe, J.M.
78:02K-040
78:02F-023
Sudhakar-Barik
78:02K-049
78:02K-053
Sumayao, A.
78:03F-062
Sumner, M.E.
78:07B-030
Sunada, O.K.
78:02F-020
78:020-049
78:048-002
Supak, J.R.
78:02K-025
Sutherland, J.C.
78:050-059
Sweeten, J.M.
78:058-067
Swoboda, A.R.
78:02K-025
Syers, J.K.
78:05A-011
Szollosi-Nagy, A.
78:02A-006
Tabatabai, M.A.
78:05A-005
Takamatsu, T.
78:02K-002
Takkar, P.N.
78:03F-006
Tal, M.
78:030005
Tandy, D.F.
78:060-002
Tang, C.
78:050-066
Tang, Y.K.
78:02F-028
Tanji, K.K.
78:03F-014
Tarasov, M.N.
78:05B-032
Taverni, A.F.
78:050-050
Taylor, A.G.
78:05G-061
Taylor, C.R.
78:068-015
Teague, W.R.
78:050-039
Templer, O.W.
78:06E-003
Terman, 0.L.
78:020-032
78:020-033
78:021-007
Terry, D.L.
78:02K-019
The Task Committee
78:068-004
Theurer, J.C.
78:03F-028
Thomas, A.W.
78:078-025
Thomas, J.C.
78:021-037
78:05A-002
Thompson, D.B.
78:05A-018
Thompson, T.
78:03F-049
Thronson, R.E.
78:050-019
Tiedemann, A.R.
78:058-049
Tiedje, J.M.
78:02K-029
Tillman, R.W.
78:05A-011
Tinney, L.R.
78:060-001
Todd, R.L.
78:05A-021
Tomlinson, J.H.
78:088-008
Touchton, J.T.
78:02K-017
78:02K-018
Toy, D.W.
78:02K-061
Toy, T.J.
78:078-033
Tribe, G.
78:03F-082
Triplett, G.B., Jr.
78:058-006
Trock, W.
78:05G-012
Trock, W.L.
78:05G-013
78:05G-014
78:050-015
Trotter, R.J.
78:060-002
Troutman, B.M.
78:04A-008
True, G.
78:05G-026
Tryon, C.P.
78:02J-007
Tscheschke, P.
78:03F-049
78:03F-060
Tubbs, L.J.
78:068-017
Tucker, T.C.
78:021-028
78:021-029
78:02K-038
78:03F-018
Turner, A.K.
78:02E-010
Turner, F.T.
78:021-037
78:058-056
Turner, T.R.
78:03F-003
Udo, E.J.
78:02K-035
Uehara, G.
78:02K-039
78:02K-060
Undan, R.C.
78:06A-006
Unger, D.G.
78:06E-020
302
-------
Unger, P.W.
78:03F-055
Unger, S.G.
78:05G-051
Unny, T.E.
78:02E-007
Unrath, C.R.
78:03F-075
Urguhart, N.S.
78:073-015
Van Es, J.C.
78:05G-055
Van Gils, J.B.H.M.
78:026-085
Van Schilfgaarde, J.
78:066-003
Vanderholm, D.H.
78:056-061
Vanecek, F.T.
78:05G-031
Veerman, G.J.
78:026-085
Verasan, V.
78:021-019
Verge, M.J.
78:048-011
Vetter, R.J.
78:058-055
Virchenko, E.P.
78:058-031
Vitosh, M.L.
78:03F-073
Vittal, N.
78:088-002
Vittetoe, G.C.
78:048-006
Vlachos, E.G.
78:056-012
78:056-013
78:056-014
78:056-015
Vlek, P.L.G.
78:02K-031
78:02K-040
Vocke, G.F.
78:06E-021
78:068-009
Waddell, T.E.
78:056-047
Wadd.ington, D.V.
78:03F-003
Wade, J.C.
78:056-003
Wagenet, R.J.
78:02K-024
78:07A-003
Waite, T.D.
78:056-030
Walker, M.E.
78:02K-041
Walker, P.H.
78:02J-018
Walker, P.N.
78:086-003
Walker, W.
78:068-019
Walker, W.R.
78:03F-020
78:058-022
78:056-009
78:056-010
78:056-011
78:06A-001
78:100-001
Wall, 6.J.
78.-02J-003
Wallace, A.
78:02K-072
Walsh, L.M.
78:03F-004
78:03F-005
78:078-002
Walter, M.F.
78:058-036
78:056-060
78:056-071
Wang, J.
78:026-031
Wann, S.S.
78:02K-039
78:02K-060
Ward, A.D.
78:02J-009
Ward, K.J.
78:078-005
Warrick, A.w.
78:026-017
78:026-041
Watanabe, F.S.
78:078-014
Watson, K.K.
78:026-003
78:048-003
Watters, G.Z.
78:088-005
Watts, D.
78:03F-060
Watts, D.6.
78:021-040
78:03F-056
78:056-045
Wauchope, R.D.
78:100-003
Weaver, R.M.
78:078-018
Weaver, R.W.
78:058-050
Webb, S.N.
78:048-003
Webber, M.D.
78:02K-012
Weed, S.B.
78:056-034
78:056-074
Weeks, L.V.
78:026-065
Weeks, W.W.
78:021-017
Welch, L.F.
78:02K-017
78:02K-018
Wells, K.L.
78:03F-027
Wells, L.G.
78:026-081
Wendt, C.W. ..
78:026-025
Wendte, L.W.
78.-03F-124
West, D.W.
78:021-002
303
-------
Westerman, P.W.
78:05A-017
Westerman, R. L.
78:02K-038
Weston, R.F.
78:05B-039
Wheaton, R.Z.
78:05G-024
Wheeler, W.B.
78:058-027
78:05B-035
Whisler, F.D.
78:020-003
White, E.L.
78:060-002
White, G.B.
78:068-011
White, J.G.
78:03F-106
White, W.C.
78:050-070
Whited, D.A.
78:03F-001
Whitehead, W.R.
78:048-013
Whiteley, H.R.
78:058-064
Whittlesey, N.K.
78:03F-011
78:058-006
78:06C-002
Wiedenfeld, R.P.
78:02K-047
78:050-001
Wierenga, P.J.
78:020-006
78:020-015
Wilding, L.P.
78:02J-003
Wilke, O.C.
78:020-025
Wilkinson, J.W.
78:05A-006
Wilkinson, W.B.
78:048-010
Willavize, S.
78:021-010
Williams, J.R.
78:040-005
78:06A-008
Williams, R.E.
78:050-048
Williams, T.H.
78:020-003
Williamson, E.J.
78:03F-113
Wilson, G.D.
78:021-025
78:021-040
Wilson, J.L.
78:058-016
Wilson, R.G., Jr.
78:058-029
Win, M.
78:02E-010
Wineman, J.J.
78:068-019
Winter, T.C.
78:02F-015
Wit, K.E.
78:020-085
Witherspoon, P.A.
78:02F-006
78:048-012
78:06A-009
Witters, R.E.
78:020-026
Wodzinski, R.S.
78:050005
78:03F-124
Wollum, A.G., II
78:058-019
Wood, E.F.
78:02A-006
Wood, J.D.
78:020-014
Woodford, T.A.
78:021-024
Woodriff, R.
78:02K-059
Woodruff, J.M.
78:021-011
Worstell, R.V.
78:03F-115
Wright, D.L.
78:021-011
Wright, J.L.
78:020-007
78:020-008
Wu, J.S.
78:058-014
Yaron, D.
78:03F-095
Yen, H.J.
78:06A-004
Yermanos, D.M.
78:021-015
Yoshida, T.
78:02K-002
Youngs, E.G.
78:020-067
Yukler, M.A.
78:02A-003
Yule, D.F.
78:020-062
Zachmann, D.W.
78:020-064
Zanker, K.
78:03F-041
78:088-003
Zaradny, H.
78:02G-002
Zhdamirov, G.G.
78:058-033
Zibilske, L.M.
78:058-050
78:020-008
304
-------
SECTION XLIII
SUBJECT-INDEX
Abstracts
78:10C-002
78:10C-006
Absorption
78:020-012
78:02G-043
78:021-028
78:02K-059
Acetylene Reduction
78:05C-003
Acidic Soil
78:02K-012
78:02K-034
78:05C-005
78:07B-018
Acidity
Acids
78.-05A-012
78:02K-044
Activation Energy
78:02K-037
Adoption of Practices
78:03F-037
Adsorption
78J02G-008
78:02G-040
78:02G-086
78:02K-010
78;02K-015
78:02K-Q25
78s02K-030
78:02K-032
78s02K-034
78:02K-035
78-.02K-036
78s02K-051
78.-02K-055
78-.02K-063
78:02K-064
78:05B-005
78:05B-016
78:05B-028
78:053-029
78:056-036
78:05B-042
Aeolian Soils
78:02K-007
Aeration
78:02K-Q52
78:07B-030
78:078-035
Aerobic Conditions
7fi:02K-009
78s02K-012
Aerobic Treatment
78:02K-029
Aesthetics
78:030-001
Aggregates
78:02J-005
78:04A-018
Agricultural Chemicals
78:05B-026
78:05C-002
78:05G-019
78:05G-037
78:050-046
78:05G-062
78:050-064
Agricultural Damages
78:05G-035
Agricultural Economics
78:03F-096
Agricultural Engineering
78:06E-005
Agricultural Runoff
78:03F-106
78:05A-011
78:05A-016
78:05A-018
78:05A-019
78:05A-020
78:05B-023
78:05B-026
78:05B-068
78:05G-034
78:050-037
78:056-064
78:05G-065
78:050-066
78t05G-067
78:056-072
78:06B-017
78:06B-020
78:06E-013
78:100-003
Agricultural Soils
78:056-034
Agricultural Watersheds
78:02A-004
78:02J-015
78:05A-019
78:05B-037
78:058-068
78:05G-024
78-.05G-046
78:050-058
78t05G-063
78:050-065
78:050-067
78-.06A-008
78:068-017
Agriculture
78:03F-036
78:03F-067
78:03F-077
78:03F-079
78:03F-124
78:05A-021
78:058-067
78rO50-003
78:050-004
78:05G-020
78:050-051
78:050-073
78:050-074
78:06A-013
78:068-007
78:068-021
78:06D-001
78:06E-009
78:06E-021
78:060-002
78:060-003
78:10C-005
Agronomic Crops
78:03F-096
Air
78s02G-011
78:020-058
Air Entrainment
78s02F-027
78:020-073
Air Pollution
78:02K-057
78s03F-024
78:040-007
.78:05A-012
78:058-054
78:05C-005
78:06B-021
Air Pollution Effects
78:05C-005
Air Temperature
78:020-006
78:078-033
Air-water Interfaces
78:08B-007
305
-------
Air-water Interactions
78:086-007
78:08B-012
Albedo
Alcohols
Alfalfa
Algae
78:03F-007
78:03F-026
78:03F-112
78:05G-001
78:021-006
78:03F-096
78:03F-125
78:05G-007
78:05G-044
78:048-003
78:056-007
78:058-010
78:05C-005
Algorithms
78:02A-002
78:02A-006
78:02F-006
Aliphatic Amines
78:05C-003
Alkali Metals
78:02K-008
Alkali Soils
78:05G-036
Alkaline Soils
78:02G-010
78:02G-023
78:03F-006
Alkalinity
78:05A-010
Alternative Costs
78:05G-035
78:068-010
Alternative Planning
78:068-019
78:06E-014
Aluminum
Amines
Ammonia
78:02K-010
78:02K-012
78:078-018
78:050-003
78:02K-017
78:02K-018
78:02K-022
78:02K-040
78:02K-043
78:03F-004
78:03F-005
78:050-003
78:05G-066
78:078-008
Ammonium Compounds
78:020-037
78:02K-001
78:02K-003
78:02K-004
78:02K-005
78:02K-013
78:02K-017
78:03F-057
78:058-049
78:05G-007
Ammonium Salts
78:021-028
Ammonium Sulfate
78:058-040
Anabaena Subcylindrica
78:050-003
Anaerobic Conditions
78:02G-035
78:02K-029
78:02K-068
Analysis
78:02F-013
78:078-018
Analytical Techniques
78:02A-003
78:02A-005
78:02F-011
78:02F-013
78:02F-020
78:02F-022
78:02G-001
78:02G-006
78:026-015
78:02G-027
78:02G-041
78:02G-068
78:02K-045
78:04A-007
78:05A-006
78:05A-015
78:05A-019
78:058-039
78.-05G-004
78:06A-010
78:078-003
78:078-019
78:088-005
Anisotropy
Apples
78:026-077
78:03F-075
Application Equipment
78:03F-071
78:03F-072
78:03F-076
78:03F-085
78:03F-086
78:03F-114
78:03F-117
78.-03F-118
Application Methods
78:03F-064
78:03F-085
78:03F-114
78:05G-045
78:050-070
78:060-002
Appropriative Rights
78:06E-007
Approximation Methods
78:02F-023
78:02F-024
Aquatic Environment
78:058-030
78:050-005
78:050-006'
Aquatic Plants
78:021-027
Aquatic Plant Control
78:020-004
Aquatic Weed Control
78:058-048
Aquatic Weeds
78:020-004
78:058-048
Aqueducts
78:088-002
Aqueous Solutions
78:026-008
78:020-022
78:02K-010
78:02K-040
Aquifer Characteristics
78:02F-006
Aquifer Management
78:048-012
78:06E-007
Aquifer Systems
78:02F-022
78:048-004
Aquifer Testing
78:02F-027
Aquifers
78:02A-003
78:02F-003
78:02F-007
78:02F-008
78:02F-009
78:02F-012
306
-------
Aquifers
(cont.)
Aquitards
78:02F-013
78:02F-014
78:02F-016
78:02F-018
78:02F-020
78:02F-021
78:04A-001
78:048-010
78:058-062
78:08E-001
78:02F-022
78:02F-023
Arid Climates
78:02K-038
78:03F-041
Arid Lands
78:05G-026
78:07B-015
Arizona
78:020-031
78:040-007
78:050-044
78:078-011
Arsenic Compounds
78:058-024
Arsenicals (Pesticides)
78:05A-002
78:058-024
Artificial Recharge
78:02K-056
78:048-002
78:048-010
Asia
78:05G-020
Asphaltic Concrete
78:080-001
Assay
78:078-016
Assessments
78:068-019
Atlantic Coastal Plain
78:02K-048
Atmosphere
78:058-041
Attenuation
78:020-075
Australia
78:02H-001
78:048-003
Autoclaves
Automatic Control
78:03F-068
78:03F-115
78:03F-116
78:03F-128
78:03F-130
Automation
78:020-016
78:03F-034
78:03F-084
78:03F-086
78:03F-115
78:03F-116
78:03F-117
78:03F-128
78:03F-130
78:078-003
78:078-026
Automation Control
78:03F-083
Backwater
78:088-008
Backwater Profiles
78:088-008
Bacteria
78:03F-090
78:058-004
78:058-019
78:05C-006
Bacteriophage
78:058-005
Barley
78:020-029
78:021-014
78:03F-027
78:03F-096
78:058-033
Basalts
78:02K-007
Base Flow
Basins
Beans
Bed Load
78:02K-033
78:058-039
78:078-026
78:020-082
78:03F-034
78:06A-003
78:068-003
78:021-024
78:021-028
78:021-029
78:02K-072
78:058-043
78:02J-013
78:02J-017
78:02J-018
78s02J-028
Bed Material Load
78:02J-013
Beds
Benefits
78:02F-014
78:02J-016
78:03F-002
78:03F-124
78:050-004
Bentonite
78:02K-073
Bermudagras s
78:02K-020
Bibliographies
78:10C-002
78:10C-006
Bioassay
78:05A-003
Biochemical Oxygen Demand
78:058-010
78:058-067
78:050-031
78:050-066
Bioindicators
78:05B-004
Biomass
78:05C-006
Bivariate Analysis
78:08E-001
Border Irrigation
78:03F-085
78:03F-099
78:03F-100
Boughton Model
78:02F-011
Boundaries (Property)
78:020-002
Boundaries (Surfaces)
78:02F-004
Boundary Layer
78:02F-010
78:02F-014
Boundary Processes
78.-02H-002
Bounding Wells
78:048-013
Boussinesq's Equation
78:02F-019
Box-Jenkins Models
78:02E-009
307
-------
Breakwater
76-.088-012
Brines
78:Q2G-065
Broraegrass
Bubbles
78:021-033
78-.03P-024
78:02G-011
Budapest (Hungary)
79.-08E-001
Bulk Density
78:020-075
Buoyancy
Burning
Cabbage
Cadmium
78-.02H-001
78:OSB-061
7S.-03F-024
78:03F-037
78:056-040
78:021-010
78:021-022
78:021-031
78:021-032
78;02K-002
7S:02K-034
78-.02K-058
76:033-055
Calcareous Soils
78:02K-013
7BJ02K-Q21
78:02K-034
78:078-010
78:07B-OL4
78:02K-045
78:056-007
78:02G-Q04
Calcite
Calcium
7S.-02K-003
78:02K-024
78:02K-035
78:02K-047
78:02K-058
Calcium Carbonate
Calcium Chloride
78:05G-Q36
Calcium Sulfate
78:02K-041
78:05G-036
Calibrations
78:G2G-014
78:076-035
Carriers
California
78:02G-050
78.-03C-C06
78-.03P-079
78:03F-080
78:03P-084
7S:G4B-001
78:048-004
76-.05A-012
78:05G-016
78.-05G-023
78-.05G-025
78:OfiD-001
78:06E-007
Canada
78:02P-026
78.-03F-070
7Bs05B-041
78:053-044
Canal Lining
78:04A-018
Canal
Canala
Canopy
78:06A-004
78:0€A-005
78:04A-018
78:02J-025
78:04A-017
Capillary Action
78:02G-043
78:02G-Q64
78t02G-068
78:04B-002
Capillary Plow
78:048-002
Capillary Water
78s02G-038
Capillary Zone
78:048-002
Carbamate Pesticides
78:02K-Q25
Carbon
89:02F-026
7e:02K-038
78.-05A-010
Carbon Dioxide
78:02r-02€
78-.02K-056
73:053-027
Carbonate Rocks
78:02P-Q26
78r02G-026
78:076-014
Cation Adsorption
78:02K-OCe
7S:02K-024
78:02K-026
78:02K-039
78{02K-058
78:C2K-070
78;07B-004
Cation Exchange
7fi:02G-037
78-.02G-045
78:02G-046
78:021-021
78s02K-003
78sQ2K-024
78-.02K-026
78:02K-035
76:02K-039
78s02K-047
78:02K-050
78:02K-058
78:02K-070
78:05H-005
78:05B-028
78:078-004
78:021-021
Cations
78-.02K-047
78:05G-042
Center Pivot Systems
79:
-------
Channels
78:02F-019
78:02J-014
78:040-008
78:05B-012
78:06B-003
78:088-003
78:088-008
Chattahoochee River
(Georgia)
78:02E-003
Chelation
78:078-012
Chemical Analysis
78:02K-009
78:02K-011
78:02K-014
78:02K-045
78:02K-059
78:02K-064
78:02K-069
78:02K-074
78:02K-075
78:05A-008
78:05A-012
78:058-003
78:078-008
78:078-014
78:078-018
78:078-019
78:078-024
78:078-028
Chemical Degradation
78:02K-042
78:05A-018
78:058-029
78:058-030
Chemical Oxygen Demand
78:05A-018
78:058-067
Chemical Potential
78:02K-063
Chemical Precipitation
78:020-045
78:02G-046
78:02K-015
78:02K-052
78:02K-065
78:02K-073
78:03C-003
78:03F-050
78:078-028
Chemical Properties
78:02J-002
78:02J-003
78:02K-006
78:02K-073
Chemical Reactions
78:02K-009
78:02K-047
78:02K-065
Chemicals
78:03F-114
Clogging
Chlorella Ellipsoidea
78:05C-003
Chloride
Chlorides
78:02K-071
78:02K-010
78:02K-064
78:050-042
Chromatography
78:020-056
Citrus Fruits
78:03F-065
78:03F-089
Civil Engineering
78:09A-001
Classification
78:068-003
Clay Loam
78:058-005
Clay Minerals
78:02K-007
78:02K-012
78:02K-025
78:02K-050
, 78:02K-073
78:058-028
Clays
Climates
78:020-007
78:020-010
78:020-024
78:020-075
78:02J-001
78:02J-002
78:02K-050
78:04A-012
78:04A-018
78:048-005
78:040-002
78:058-040
78:060-002
Climatic Data
78:02A-007
78:02A-008
78:02A-009
78:020-005
78:020-068
78:020-074
78:021-003
78:021-005
78:021-035
78:03F-049
78:03F-123
78:078-033
Clovers
78:03F-032
78:03F-050
78:03F-087
78:03F-088
78:03F-090
78:058-033
78:078-006
Coagulation
78:050-038
Coal Mine Spoil
78:020-071
Coal Mine Wastes
78:021-024
COals
78:068-004
Coastal Engineering
78:088-012
Coastal Plain Soils
78:050-034
Coastal Plains
78:02K-041
78:068-020
78:078-036
Cohesive Soil
78:02J-002
Coliforms
Colloids
Colorado
78:05A-015
78:058-004
78:058-052
78:050-066
78:02K-039
78:02K-060
78:02K-031
78:050-028
78:078-012
78:08A-001
Colorado River
78:03C-006
78:03F-032
78:040-007
78:050-022
78:050-028
78:050-035
78:050-075
78:06E-006
Colorado River Basin
78:03C-006
78:058-012
78:058-038
309
-------
Colorado River Basin
(cont.)
78:05G-022
78:050-028
78.-05G-075
78:06E-006
78:07^-003
Colorimetry
78:076-003
Columbia River
78:06A-007
78:06C-002
Compacted Soils
78:020024
Compaction
78.-02G-024
Comparative Benefits
78;03F-037
Comparative Costs
78:02J-007
Coraparative Productivity
78:03F-037
Compressible Flow
78:02P-009
Computer Models
78.-02A-002
78:02E-004
76:02F-028
78:02G-038
78:02G-059
78:02G-060
78:02J-019
78:02K-004
78:02K-005
78:03P-046
78:03F-049
78:03F-068
78-.03F-101
78:03F-102
78:048-008
78:043-011
78:056-014
78:05G~072
78:06A-003
78;06A-006
78:06A-009
78:06A-010
78:06A-014
78:06D-001
Computer Programs
78:02G-057
78:02J-009
78:02J~017
78:03F-046
78:03F-049
78:03F-058
78.-03F-068
78:03F-086
78:03F-101
78:03F-102
78:03F-103
78:04A-009
78:04B-012
78:04B-013
78:050-039
78:050-072
78:06A-010
78:076-021
Conceptual Model
78.-05G-033
Concrete Structure
78:08E-001
Conduits
78:088-008
Conference
78:05G-071
78:10A-001
Confined Water
78:03F-110
Connecticut River
78:05A-009
Conservation
78:02J-021
78:03F-10&
78:05G-064
78-.05G-071
78:06G-002
78:09C-001
Constraints
78:058-009
Construction Costs
78:0€A-006
78:07B-027
Consumptive Use
78:02D-003
78:030-001
78:03F-077
78-.03F-109
78J03F-118
Contaminant Arrival
Distributions
78:056-059
Continuity Equation
78:02G-053
78.-04B-011
Contour Farming
78:02J-020
Contour Furrowing
78-.03F-059
Control
78:05A-008
Control Systems
78:03F-068
78:03F-115
78:03F~116
78:03F-117
78:03F-118
Convection
78:02G-044
78:02G-008
78:02G-077
78.-02G-078
78:02K-062
73:03F-056
Conveyance Structures
78:03F-130
Cooling
78.-03F-075
Cooling Levels
78:05G-03L
Cooling Towers
78:05C-001
Cooling Water
78:04B-001
78t05B-061
Copper
Core
Cores
Corn Belt
78:021-032
78:02K-002
78.-02K-027
78s02K-034
7B:02K-072
78:02G-085
78:073-001
78.-07B-005
78:05G-058
78:066-007
Control Structures
78;05G-024
Corn (Field)
78.-02A-001
78:0211-003
78:02E-011
73:02F-002
78:026-032
78:02G-033
78:021-012
78:021-018
78:021-019
78;Q2I-024
78;02I-025
78:021-032
78:021-034
78:021-040
78:021-041
78:021-042
78.-03F-004
78:03F-008
78;03F-023
310
-------
Corn (Field)
(cont.)
78:03F-048
78:03F-051
78:03F-060
78:03F-108
78:03F-123
78:03F-125
78:04A-012
78:05B-006
78:058-055
78:050-007
78:05G-029
78:05G-045
78:07B-013
78:07B-024
Correlation Analysis
78:021-003
78:021-005
78:021-006
78:021-012
78:021-032
78:068-003
78:07B-013
Cost Allocation
78:03F-101
Cost Analysis
78:048-011
78:068-007
78:07B-011
Cost-Benefit Analysis
78:05G-023
78:068-010
Cost Comparisons
78:02J-007
78:02J-020
78:03F-083
78:03F-084
78:068-010
78:078-011
78:08A-001
Cost-Effectiveness
78:05G-010
Costs
Cotton
78:02J-006
78:03F-087
78:03F-101
78:05G-004
78:050-033
78:050-035
78:06C-001
78:06C-002
78:021-003
78:02J-012
78:02K-005
78:03F-047
78:058-024
Cover Crop
78:04A-017
Critical Days
78:03F-095
Critical Flow
78:078-001
78:078-027
78:088-002
Crop Pattern
78:04A-003
Crop Production
78:02A-001
78:02G-029
78:02G-033
78:021-006
78:021-018
78:021-024
78:021-025
78:021-026
78:021-028
78:021-029
78:021-030
78:021-035
78:021-036
78:021-040
78:03F-002
78:03F-018
78:03F-019
78:03F-022
78:03F-027
78:03F-028
78:03F-031
78:03F-035
78:03F-036
'78.-03F-037
78:03F-048
78:03F-049
78:03F-052
78:03F-061
78:03F-062
78:03F-063
78:03F-065
78:03F-070
78:03F-071
78:03F-092
78:03F-106
78:03F-108
78:03F-112
78:04A-009
78:04A-010
78:048-005
78:048-007
78:048-008
78:050-007
78:05G-021
78:050-023
78:050-025
78:050-076
78:06A-013
78:068-021
78:060-002
78:06E-021
78:060-001
78:078-024
78:10C-005
Crop Response
78:02F-002
Crops
78:020-
78:02G-
78:02G-
78:021-
78:021-
78:021-
78:021-
78:021-
78:021-
78:021-
78:021-
78:021-
78:021-
78:021-
78:02K-
78:03C-
78:03C-
78:03C-
78:03F-
78:03F-
7 8:0 3F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:048-
78:058-
78:05G-
78:078-
78:078-
•029
•032
•033
•005
•007
•010
•016
•018
•025
•026
•028
•034
•035
•042
•005
•002
•003
•004
•004
•006
•019
•023
•025
•027
•028
•031
•048
•055
•061
•062
•063
•095
096
005
•055
021
013
024
78:02E-010
78:020-031
78:03F-009
78:03F-113
78:058-006
78:060-001
78:060-002
Cryogenics
78:02C-001
Crystal Growth
78.-02C-001
Crystalline Rocks
78:02F-026
Cultural Control
78:03F-002
78:03F-080
78:05G-024
Culverts
78:088-002
Dairy Industry
78:06A-016
78:068-011
311
-------
Dams
78:02F-008
Danube River
78:08E-001
Darcy-Weisbach Equation
78:08B-005
78:08B-010
Darcys Law
78:02G-007
78:02G-018
78:02G-059
78:088-012
Data Collections
78:02J-021
78:03F-039
78:05B-001
78:07B-013
78:076-023
78:078-028
Data Processing
78:02J-010
78;04D-001
78:040-004
DDT
78:058-033
Deaeration
78:076-030
Decision Making
78:04A-001
78:050-031
78:050-062
78:06A-013
78:06E-014
78:06E-015
Decision Theory
78:08E-001
Decomposing Organic Matter
78:02K-022
78:03F-023
Deficient Elements
78:021-024
Deflection
78:080-002
78:080-003
Deformation
78:06A-009
Degradation (Decomposition)
78:02K-017
78:058-056
Denitrification
78:020-035
78:020-036
78:020-050
78:02K-018
78:02K-020
78:02K-029
78:02K-038
78:02K-048
78:02K-057
78:02K-061
78:02K-067
78:02K-068
78:02K-071
78:03F-004
78:03F-010
78:03F-013
78:03F-016
78:03F-017
78:03F-057
78:05A-004
78:05A-009
78:058-018
78:058-025
78:058-043
78:058-047
78:058-064
78:050-008
78:050-034
78:050-074
78:050-077
78:078-023
Deposition (Sediments)
78:02J-026
Depth
78:02F-021
78:020-022
78:02K-038
78:04A-002
Desalting
78:050-010
Desert Plants
7Bs02I-015
Deserts
78:02K-038
Delaware
78:020-003
78:058-037
78:068-020
Desiccants
78:058-024
Design
78:02J-009
78:03E-093
78:03F-098
78:048-009
78:078-015
78:078-028
78:088-010
Design Criteria
78:02J-006
78:03F-058
78:03F-082
78:03F-099
78:03F-127
78:08A-004
Design Data
78:02J-028
Design Flow
78:07A-002
Design Standards
78:08A-004
Design Storm
78:02E-002
Desorption
78:020-003
Detention Reservoir
78:02J-007
78:02J-009
78:06A-016
78:08A-004
Diazinon
Dibron
Dicots
78:05B-040
78:058-040
78:078-005
Diffusion
78:020-004
78:020-008
78:020-035
78:020-036
78:020-040
78:020-045
78:020-060
78:020-061
78:02H-001
78:021-002
78:02J-014
78:02K-026
78:02K-036
78:02K-061
78:02K-062
78:03F-056
78:078-030
78:078-035
78:088-001
Diffusivity
78:020-049
78:020-059
78:02H-002
78:021-013
78:021-021
78:02K-036
Digital Computers
78:02A-002
Dimensional Analysis
78:020-082
Discharge
78:08B.-009
Discharge Measurement
78:048-009
312
-------
Disease Resistance
78:06G-001
Distribution Systems
78:03F-098
Diseases
78:06G-001
Dispensing
78:02E-003
Dispersion
Disposal
78:02G-008
78:02G-012
78:02G-013
78:02G-015
78:02G-045
78:02G-060
78:02G-062
78:02J-014
78:02K-062
78:056-013
78:05B-016
78:053-017
78:058-061
78:050-030
78:088-013
78:058-004
Dissolution
78:02G-013
Dissolved Inorganic
Phosphates
78:05A-011
Dissolved Organic Carbon
78:05A-010
Dissolved Oxygen
78:05A-010
78:058-010
78:05B-065
78:056-031
Dissolved Solids
78:02G-013
78:058-012
Distribution
78:028-001
78:02J-014
78:03F-030
78:03F-098
78:03F-103
78:03F-104
78:03F-110
78:068-005
Distribution (Patterns)
78:02J-014
78:03F-054
78:03F-071
78:03F-076
78:03F-092
78:03F-097
78:03F-103
78:03F-104
78:03F-126
Ditches
Diurnal
78:02F-019
78:04A-002
78:05G-011
78:078-011
78.-02F-021
78:02G-031
78:02K-043
78:048-003
Diversion
78:02J-008
78:04A-009
Diversion Structures
78:02J-008
Drag
78:02J-017
Drainable Porosities
78:02G-081
Drainage
78:02G-003
78.-02G-057
78.-02G-058
78:02G-077
78:02G-078
78:02G-081
78:021-002
78:02J-026
78:030-006
78:03F-040
78:03F-044
78:03F-096
78:048-007
78:048-008
78:048-012
78:040-001
78:058-001
78:058-021
78s05G-023
78:05G-025
78:05G-026
78:06A-006
78:068-003
78:06C-001
78:06G-003
78:078-022
78:08A-002
78:088-003
78:08G-002
78:080-003
Drainage Area
78:05G-025
Drainage Control
78:050-034
Drainage Density
78:056-018
Drainage Effects
78:04A-015
78:05G-002
78:050-018
78:05G-074
78:06A-006
Drainage Practices
78:03C-006
78:04A-015
78:048-006
78:048-008
78:08A-002
Drainage Problems
78:050-023
Drainage Programs
78:03C-006
Drainage Systems
78:048-007
78:048-008
78:05G-018
Drainage Water
78:026-039
78:02K-052
78:04C-001
78:058-046
78:05G-018
78:056-020
78:050-044
78:05G-074
Drains
78:02F-028
78:03F-124
78:04A-002
78:04A-005
78:088-003
Drawdown
78:02A-003
78:02F-003
78:02F-009
78:02F-012
78:02F-016
78:02F-018
78.-02F-027
78:04A-005
78:.04B-009
Drifting (Aquatic)
78:050-001
Drilling
78:050-025
Drops (Fluids)
78:03F-071
Drought Resistance
78:03F-047
Drought Tolerance
78:021-015
Droughts
78:02A-002
313
-------
Dry Farming
78:021-008
78:04A-010
Drying
78:02G-030
78:020-067
78:020-080
78:02G-084
78:07B-017
Drying Curves
78:026-063
Dust
78:040-007
Dye Releases
78:02E-003
Dynamic Programming
78:03F-101
Dynamics
78:02G-056
78:026-074
78:08B-001
Earth Dams
Ecology
78:02F-008
78:02K-023
78:05B-054
78:06G-002
Economic Analysis
78:03F-009
78:06B-002
Economic Efficiency
78:03F-022
78:04A-003
78:04A-004
78:05G-031
78:05G-035
Economic Feasibility
78:02J-020
78:03F-066
78:048-005
78:05G-047
Economic Impact
78:02J-020
78.-05G-016
78:050-035
78.-05G-058
78:056-075
78:06A-007
78:063-007
78:063-011
78:068-012
78:063-014
78:063-015
78:068-021
78:06E-015
78:066-002
Economic Justification
78.-02F-022
78:04A-010
Economic Prediction
78:068-001
78:068-007
78:068-009
78:068-021
Economics
78:03F-037
78:03F-092
78:03F-108
78:03F-124
78:060001
78:06E-002
78:06E-021
Economies of Scale
78:058-009
Ecosystems
78:02K-011
78:06A-002
78:06A-014
78:078-016
Edge Effects
78:026-005
Education
Effects
78:09A-001
78:04A-001
78:056-033
Efficiencies
78:03F-038
78:03F-082
78:068-005
78:08C-001
Efficiency
78:03F-020
Effluents
78:02K-015
78:03F-015
78:058-021
78:058-061
78:050007
Eggplant
78:058-040
Electric Power Costs
78:03F-052
78:080001
Electric Power Demand
78:03F-069
Electric Power Rates
78:080001
Electrical Conductance
78:026-010
78:026-014
78:02G-030
Electrical Resistance
78:078-030
78:078-035
Electrodes
78:02K-002
78:07B-030
Electronic Equipment
78:03F-115
78:03F-116
78:03F-117
78:03F-118
78:083-009
Elements (Chemical)
78:021-032
78:02K-006
78:078-019
Emerging Vegetation Stage
78:026-029
Energy
78:03F-067
78:03F-086
78:03F-113
78:048-014
78:068-004
78:060002
Energy Conversion
78:03F-066
78:03F-067
78:03F-086
Energy Budget
78:03F-007
Energy Conservation
78:026-059
Energy Costs
78:080001
Energy Dissipation
78.-02J-028
Energy Gradient
78:08B-006
Energy Loss
78:03F-034
78:088-006
Engineering
78:09A-001
Engineering Education
78.-09A-001
Engineering Structures
78:08A-001
Entrainment
78:088-012
314
-------
Environment
78:02K-066
78:058-050
78:06E-021
Environmental Control
78:02K-042
78:05G-051
78:068-010
78:06E-011
Environmental Effects
78:02A-006
78:021-033
78:02J-011
78:046-004
78:058-011
78:058-033
78:058-055
78:058-057
78:058-058
78:058-059
78:058-060
78:05C-001
78:050-002
78:06A-002
78:06A-003
78:068-001
78:06B-014
78:06G-003
Environmental Sanitation
78:02K-071
78:05G-051
78:05G-070
Equations
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
:02A-011
:02E-010
:02F-001
:02F-003
:02F-004
:02F-006
:02F-007
:02F-010
.-02F-012
:02F-016
.-02F-018
:02F-019
:02F-028
:02G-001
:02G-002
:02G-004
:02G-006
:02G-018
:02G-022
:02G-024
:02G-041
:02G-042
:02G-048
:02G-055
:02G-061
:02G-073
:02J-013
:03F-095
:04A-002
.-058-017
:05B-057
:05B-058
:05G-031
: 088-007
Equilibrium
78:02K-047
Equipment
78:02G-011
78:02G-014
78:03F-039
78:05G-026
78:06C-001
78:078-011
78:078-015
78:08A-001
Erodibility
78:02J-001
Erosion
78:02G-013
78.-02J-001
78:02J-002
78:02J-007
78:02J-012
78.-02J-015
78:02J-021
78:02J-024
78:02J-027
78:04A-013
78:04A-017
78:040-001
78:040-004
78:040-005
78:040-006
78:040-008
78:058-003
78:058-036
Erosion Control
78:021-011
78:02J-006
78:02J-020
78:02J-021
78:040-004
7.8:05G-048
78:05G-058
78:068-011
78:068-012
78:068-015
Erosion Rates
78:02J-001
78:02J-002
Estimating Equations
78:020-006
78:02G-034
78:02G-072
78:02G-082
78:02G-083
78:03F-126
78:078-033
Estimating
78:020-003
78:02E-001
78:02E-005
78:02E-011
78:02G-065
78:02G-082
78:030-001
78:03F-095
315
Ethers
78:058-031
78:058-033
78:05C-002
78:05G-035
78:05G-063
78:078-013
78:088-011
78:05G-001
Eutrophication
78:02K-032
78:058-007
78:05C-006
78:05C-007
78:05G-008
78:05G-067
Evaluation
78:03F-091
78:03F-099
78:03F-104
78:05A-015
78:058-014
78:068-019
78:09A-001
Evaporation
78:020-002
78:020-017
78:020-021
78:021-003
78:038-001
78:03F-007
78:03F-081
78:03F-097
78:03F-112
78:03F-118
78:058-033
Evapotranspiration
78:02A-008
78:02A-010
78:02A-011
78:020-003
78:020-004
78:020-005
78:020-007
78:020-008
78:02F-018
78:02G-038
78:021-003
78:021-004
78:021-006
78:021-025
78:021-034
78:021-036
78:021-037
78:021-042
78:03F-007
78:03F-026
78:03F-031
78:03F-033
78:03F-048
78:03F-049
78:03F-079
78:03F-109
78:03F-123
78:050-044
78:068-009
-------
Excess Water
78:03F-096
Excessive Precipitation
78:02A-005
Expansive Soils
78:02J-002
Failure (Mechanics)
78:08E-001
78:08G-002
78:08G-003
Fallowing
78:03B-001
78:03F-055
78:04A-012
78:058-044
Farm Equipment
78:04B-014
Farm Management
78.-03F-124
78:056-001
78:058-006
78:05G-060
Farm Wastes
78:02F-002
78:058-040
78:058-067
Feasibility Studies
78:048-011
Feature Prediction Model
78:02E-007
Federal Government
78:06E-020
Federal Project Policy
78:06E-011
78:06E-020
Federal Water Pollution
Control
78:056-071
78:06E-010
78.-06E-020
Feed Barley
78:03F-096
Feed Lots
78:05A-016
78:05C-003
78.-05G-076
Feeds
78.-03F-113
Fertility
78:03F-003
Fertilization
78:020-051
78:021-005
78:021-006
78:021-016
78:021-026
78:021-030
78:02K-001
78:02K-004
78:02K-005
78:02K-036
78:02K-040
78:02K-043
78-.02K-057
78:03F-001
78:03F-002
78:03F-003
78-.03F-006
78:03F-012
78:03F-015
78:03F-017
78:03F-024
78:03F-061
78.-03F-065
78:03F-073
78:03F-114
78:058-020
78:058-043
78:058-044
78:05B-046
78:058-049
78:05G-005
78:056-029
78:050-039
78:078-013
78:078-023
78i07B-024
78:10C-002
Fertilizers
78:02F-002
78:02G-032
78:020-033
78:021-007
78:021-009
78:021-017
78:021-022
78:02K-001
78:02K-009
78:02K-013
78:02K-017
78:02K-018
78:02K-019
78.-02K-020
78:02K-021
78:02K-031
78:02K-063
78.-02K-066
78:02K-069
78:03F-004
78:03F-005
78:03F-008
78:03F-018
78:03F-019
78:03F-025
78:03F-036
78:03F-052
78:03F-057
78:03F-059
78s03F-067
78:03F-114
78:048-014
78.-04D-003
316
78:058-001
78:058-025
78:058-040
78:05G-007
78.-05G-021
78:05G-037
78-.05G-070
78:05G-077
78:068-012
78:06E-021
78:078-012
78:100001
Fescues
78:021-007
78:03F-024
78:078-009
Field Capacity
78.-02G-038
78:02G-079
Filters
78:04A-005
Filtration
78:02J-022
78.-03F-032
78:03F-045
Financing
78:05G-023
Finite Element Analysis
78:02G-048
78:02F-019
78:02F-022
78-.02F-024
78:02P-025
78:02G-057
78:02G-059
78:02J-024
78:048-011
78:048-012
Fissures (Geologic)
78:02F-012
Flexible-Flap Drain
Valves
78:088-003
Flexibility
78:03F-084
Float Plan
Floats
78:020-004
78:03F-053
Flocculation
78:05G-038
Flood Discharge .
78:02A-009
Flood Irrigation
78:02G-051
78:021-037
78:02K-001
-------
Flood Irrigation
(cont.)
78:053-002
78:058-047
Flood Routing
78-.02J-024
Flooding
Floods
Florida
Flow
78:02G-035
78:020-036
78:02K-027
78:02K-049
78:02K-053
78:03F-040
78:03F-057
78:02E-002
78:021-027
78:02K-070
78:03F-065
78:02E-010
78:02F-003
78:02F-009
78:02F-010
78:02F-012
78:02F-013
78:02F-Q14
78:02G-002
78:02G-007
78.-02G-009
78:020-013
78:08B-003
78:08B-008
Flow Around Objects
78:02F-025
Flow Characteristics
78:02G-078
78:02J-016
78:088-002
Flow Control
78:03F-053
78:03F-059
78:083-007
Flow Duration
78:07B-026
Flow Friction
78:088-010
Flow Measurement
78:07B-011
78:07B-027
78:086-009
Flow Nets
78:058-062
Flow Profiles
78:088-008
Flow Rates
78:021-004
78:02J-019
78:03F-064
78-.03F-093
78.-03F-100
78:03F-102
78:043-006
78-.05B-062
78:06A-005
78:08B-004
78:088-006
Flow Resistance
78:021-004
Flow System
78:02G-078
Fluid Flow
78:05B-061
Fluid Infiltration
78:058-022
Fluid Mechanics
78:02G-053
Flumes
78:078-011
78:07B-027
78:08B-009
Fluorometry
78:078-018
Flushing
78:025-011
Fluvial Sediments
78:02J-003
Fly Ash
Foliar
78:021-024
78:05G-029
Foliar Application
78:05G-029
Forage Grasses
78:021-016
78:078-009
Forage Sorghum
78:02K-021
Forecasting
78:02A-006
78:02E-005
78:02F-011
78:06A-008
Forest Fires
78:058-049
Forest Management
78:056-065
78:056-047
78:050-051
317
78:05G-069
78:06A-014
78:06A-015
Forest Soils
78:05A-012
Forest Watersheds
78:02A-011
78:05A-021
78:058-065
78:056-069
Forestry
78:06A-014
Fossil Fuels
78:021-024
Fourier Analysis
78:02G-044
Fractional Gaussian
Noise Algorithms
78:02E-004
Free Surfaces
78:04A-002
78:083-007
Freezing
78:02C-001
78:02G-020
78t02G-025
78:03F-074
78:03F-075
Frequency
78:048-003
Frequence Analysis
78:05G-065
Frequency Curves
78:03F~064
Frost Heaving
73:02C-001
78:078-022
Frost Protection
78:03F-074
78:03F-075
Froude Number
78:058-061
Frozen Soils
78:02G-020
78:02G-025
Fruit Crops
78:03F-075
78:03F-080
Fumigants
78:056-054
Furrow Irrigation
78:02G-083
78:03F-054
-------
Furrow Irrigation
(cont.)
78:03F-059
78:03F-080
78.-03F-085
78.-03F-115
78:03F-117
78:04D-008
78:073-021
Grading
Furrows
Gages
78:02G-083
78:078-015
Gamma Rays
78:02G-016
78:02G-075
Gamma Scanning System
78.-02C-001
Gas Chromatography
78:05B-048
78:073-023
Gas Flux
Gases
78:05A-009
78:063-004
Geochemistry
78:02F-026
78:02K-006
Geometric Mean
78:05A-015
Geomorphology
78:063-003
Geophysics
Georgia
78:02E-009
78:02F-021
78:02E-003
78:040-007
78.-05G-026
Gradually Varied Flow
78:088-008
Grain Sorghum
78:03F-047
78:03F-055
78:04A-017
Grains (Crops)
78:02E-011
78:021-005
78:03F-022
Grand Traverse Bay Region
78:05A-001
Granules
78.-02G-026
78.-02K-041
78:08B-012
Grapefruit
78:021-003
78:03C-004
Graphical Analysis
78:02G-022
78:02J-004
Graphical Methods
78:02J-004
78:03F-100
78:083-002
78:088-005
Grasses
Gravels
78:021-011
78:02J-022
78:03P-024
78:02G-021
78:04A-018
Geothermal Studies
78:043-001
Germination
78:02G-029
78:021-011
Glacial Lake Souris Basin
78:026-079
Golf Courses
78:05A-002
78:053-011
Gravimetric Analysis
78:073-022
78:078-034
Gravitational Water
78.-02G-049
Grazing
78.-04A-006
78:05G-019
Graded
78:02J-006
Gradient Search Procedure
78:056-031
Great Lakes
78:020-002
78:05A-016
78:05G-046
78:05G-067
Great Plains
78:021-006
78:06B-007
Greenhouses
78.-02G-032
78.-02G-033
78:026-037
78:021-043
78:078-014
Groundwater
78:02A-003
78:02A-008
78:02A-010
78:02F-003
78:02F-005
78:02F-008
78:02F-009
78:02F-010
78:02F-012
78.-02F-014
78.-02F-016
78.-02F-019
78:02F-020
78:02F-021
78:02F-024
78:02F-026
78:02F-027
78:02K-048
78:04A-005
78:043-003
78:04B-006
78:043-010
78:05A-001
78:05A-010
78:058-016
78:053-017
78:058-035
78:053-039
78:053-047
78:053-052
78:053-057
78:053-058
78:056-016
78:05G-028
78:05G-045
78:056-076
78:05G-077
78:063-009
78:065-003
78:06E-007
78:08A-002
78;08B-003
78.-08E-001
78:10C-002
78tlOC-005
Groundwater Basins
78:043-004
78:048-011
78:06D-001
Groundwater Contamination
78:05B-060
Groundwater Mounds
78:02F-001
78:043-002
Groundwater Movement
78:02A-003
78.-02F-004
318
-------
Groundwater Movement
(cont.)
78:02F-006
78:02F-007
78:02F-008
78:02F-009
78:02F-010
78:02F-012
78:02F-014
78:02F-015
78.-02F-016
78:02F-018
78:02F-022
78:02F-023
78:02F-024
78:02F-025
78:02F-028
78:02G-019
78:04A-002
78:048-011
78:046-012
78:048-013
78:058-016
78:058-017
78:058-039
78:058-057
78:058-058
78:058-059
78:058-060
Groundwater Quality
78:058-039
Groundwater Recharge
78:02F-001
78:02F-005
78:02K-056
78:048-002
78:048-003
78:058-059
78:058-060
78:06E-003
78:10C-002
Groundwater Resources
78:058-059
78:058-060
78:068-004
Growth Chambers
78:021-002
78:021-014
78:021-033
Growth Rates
78:03F-021
Growth Stages
78:020-003
78:021-001
78:021-025
78:021-026
78:021-034
78:021-036
78:021-040
78:021-041
78:021-042
78:030-002
78.-03F-031
78:03F-033
Guam
Gullies
78:03F-048
78:03F-051
78:068-009
78:078-007
78:058-040
78:02J-011
78:04A-009
78:058-012
Gully Erosion
78:02J-011
78:04D-006
Gypsum
Hardwood
78:02G-013
78:02K-003
78:02K-028
78:02K-041
78:03F-006
78:05G-036
78:02A-011
Harp Lake
Hay
78:058-041
78:021-016
78:03F-057
Hazen-Williams Equation
78:088-005
78:088-006
78:088-010
Head Loss
78:02F-028
78:088-005
Heat Flow
78:02G-020
Heat Flux
78:02H-002
Heat Transfer
78:020-001
78:058-061
Heated Water
78:053-015
Heavy Metals
78:021-022
78:021-032
78:02J-003
78:02K-002
78:02K-034
78:05A-005
78s05B-055
Herbicides
78:02K-016
78:02K-042
78:02K-062
78:03F-036
78:040-003
78:058-006
78:058-023
78:058-026
78:058-027
78:058-034
78:058-035
78:058-048
78:10C-003
Heterogeneity
78:02G-053
78:02J-005
Highway Beautification
78:021-011
Highway Effects
78:04C-001
History
78:088-009
Homogeneity
78:02J-005
Horizontal Infiltration
78:02G-034
Hudson River
78:05G-050
Humic Acids
78:02K-002
Humid Areas
78:03F-078
78.-03F-089
78:048-007
Humid Climates
78:020-003
78:03F-065
78:03F-073
78:03F-078
78:048-007
Humidity
Hungary
78:020-006
78:08E-001
Hurst Coefficient
78:02E-004
Hydration
78:02K-008
Hydraulic Conductivity
78:02A-003
78:02F-001
78:02F-007
78:02F-016
78:02F-017
78:02F-023
78:02F-028
78:02G-010
78:02G-018
319
-------
Hydraulic Conductivity
(cont.)
78.-02G-024
78-.02G-028
78.-02G-034
78:02G-042
78:020-044
78:02G-049
78:02G-054
78:02G-055
78:02G-057
78:02G-061
78:02G-064
78:02G-073
78:02G-084
78.-02G-085
78:021-008
78:02J-019
78:030003
78:03F-093
78:03F-110
78.-04A-018
78:048-009
78.-07B-036
78:088-012
Hydraulic Conduits
78:088-010
Hydraulic Design
78:088-002
Hydraulic Equipment
78:078-001
Hydraulic Gradient
78:02F-007
Hydraulic Models
78:088-004
Hydraulic Properties
78:020-073
78:088-004
78:083-005
Hydraulic Valves
78:088-003
Hydraulics
78:02E-003
78:02J-013
78:05B-013
78:088-007
78:088-008
78:088-011
78:088-012
Hydrodynamics
78:020-015
78;04A-007
78.-06A-004
Hydroelectric Power
78:06A-007
Hydrogen Ion Concentration
78:02K-010
78:02K-043
78:02K-044
78.-02K-051
78:058-042
78:05G-001
Hydrogeology
78:02F-015
Hydrographs
78:02A-005
78.-02J-012
78:04A-006
78:078-032
Hydrologic
78:02A-011
Hydrologic Aspects
78.-02J-009
78:04A-006
78:05A-020
78:068-004
Hydrologic Budget
78:020-002
78:036-001
78:03F-026
78:050-072
Hydrologic Cycle
78:02A-010
78.-02A-011
Hydrologic Data
78:02E-007
78:02F-011
Hydrologic Properties
78:02A-010
78:020-060
78:078-036
Hydrological Extremes
78:02E-001
Hydrology
78:02A-004
78:02A-005
78:02A-010
78:020-001
78:02E-004
78:02E-007
78:02E-008
78:02E-009
78:02F-014
78:02F-019
78:020-055
78:05B-059
78:058-060
78:068-004
Hydrolysis
78:02K-053
78:02K-074
78:03F-029
78:058-029
Hydrometry
78:08B-009
Hysteresis
320
78:02G-003
78:020-063
78:02G-067
Ice
Idaho
Illinois
Illite
78:02G-080
78.-02K-037
78:02H-002
78:02J-008
78:02J-010
78:02J-015
78:03F-036
78i03F-052
78:03F-107
78:05C-006
78:07A-001
78:058-001
78:05G-061
78:02J-002
78:02K-025
Imperial Valley
78:048-001
Impermeable Beds
78:02F-014
Impervious Soils
78:02F-010
78:02F-014
Improvement
78:050-033
Income
78:03F-096
Incubation
Indiana
78:020-035
78:02G-051
78:02K-014
78:02A-001
78:02K-070
78:058-068
Indicators
78:03F-021
Industrial Plants
78:05B-055
Industrial Wastes
78:02K-011
78.-05C-002
Infiltration
78:02A-007
78.-02A-009
78:02D-005
78j02F-001
78:02G-001
78:020-005
78:020-009
78:020-015
78:020-019
78:020-021
-------
Infiltration
(cont.)
78:02G-023
78:02G-027
78:02G-028
78:02G-034
78:02G-041
78:02G-043
78:02G-044
78:02G-048
78:02G-052
78:02G-055
78.-02G-058
78:020-059
78:02G-061
78:02G-064
78.-02G-067
78:02G-068
78:02G-072
78:02G-073
/H:02G-075
78:02G-082
78:02G-083
78:02G-085
78:026-086
78:03F-037
78:03F-054
78:03F-093
78:03F-100
78.-03F-110
78:04A-006
78:04A-007
78:048-012
78:05G-001
78:07B-021
Infiltration Models
78:02G-055
Infiltration Rates
78:02G-055
78:02G-058
78:02G-059
78:02G-067
78:020-072
78:02G-083
78:03F-037
78:03F-099
78:04A-006
78:076-021
Infiltrometer
78:02G-005
78:073-021
Inflow
78:04A-008
Infrared Radiation
78:02F-021
Inhibitors
78:02K-017
78:02K-018
78:02K-022
78:02K-029
78:03F-004
78:03F-005
78.-03F-029
78:05A-005
78:058-011
78:078-002
78:078-003
Initial Temperature
78:02H-002
Injection' .
78:03F-114
Injection Wells
78:048-013
Inorganic Compounds
78:02K-006
78:02K-014
78:02K-015
78:02K-022
Input-Output Analysis
78:02A-006
78:056-035
Insecticides
78:02K-025
78:10C-003
Installation
78:03F-043
78:048-006
78:05G-026
78:060-001
78:08A-002
78:08G-002
78:08G-003
Institutional Constraints
78:05G-047
78:068-012
78:06E-015
78:06G-003
Institutions
78:06A-007
Instrumentation
78:02G-005
78:02G-011
78:02G-014
78:020-016
78:026-062
78.-02J-001
78:03F-115
78:03F-116
78:03F-117
78:078-015
78:078-030
78:078-032
78:08A-001
78:088-009
Intermittent Streams
78:078-032
International Field Year
78:02D-002
Investment
78:06C-001
Ion Exchange
78:026-065
78:021-023
78:02K-010
78:02K-060
Ion Transport
78:02G-065
78:02K-060
78:02K-064
78:056-039
78:078-026
Ions
Iowa
78:02K-008
78:03C-005
78:03F-021
78:03F-108
78:040-006
78:058-008
78:068-012
Iron
Intakes
78:026-083
Integrated-Finite-
Difference Method
78:02F-006
Interception
78:06A-004
78:06A-005
321
78:021-027
78:02K-027
78:02K-052
78:02K-072
78:078-019
Iron Oxides
78:02K-010
78.-02K-030
78:02K-051
78:05D-001
Irradiation
78:078-009
Irrigated Agriculture
78:03F-009
Irrigated Land
78:026-039
78:03F-014
78:03F-016
78:03F-042
78:03F-098
78:056-005
78:056-012
78:056-013
78:056-014
78:05G-015
78:056-026
78:06A-004
78:068-007
78.-06E-001
78:06E-003
78:066-001
78:066-003
78:10A-001
78:10C-001
-------
Irrigation
78:
78:
78:
78:
78:
78:
78:
78:
78s
78:
78;
78;
78:
78:
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78;
78:
78:
78:
78;
78;
78;
78:
78;
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
02D-007
02D-008
02G-011
02G-021
02G-025
02G-030
02G-041
02G-082
:02I-002
:02I-025
;02I-033
1021-034
:02I-040
:02I-042
:02J-008
:02J-015
:02K-055
:03C-003
:03F-002
:03F-008
:03F-020
:03F-026
:03F-030
:03F-031
:03F-033
:03F-035
:03F-039
:03F-040
:03F-041
:03F-042
:03F-043
:03F-044
:03F-047
:03F-049
:03F-052
:03F-056
:03F-059
03F-061
03F-062
03F-064
03F-065
03F-066
03F-067
03F-068
03F-073
03F-078
;03F-080
:03F-086
;03F-087
:03F-088
:03F-089
;03F-090
S03F-095
:03F-097
:03F-098
:03F-101
:03F-102
:03F-103
:03F-104
:03F-106
:03F-107
:03F-109
:03F-110
:03F-112
:03F-114
:03F-123
:03F-125
:03F-128
78:03F-130
78:04A-016
78:040-008
78:05A-009
78:056-018
78:05B-022
78:05G-009
78:050-011
78:05G-012
78:050-013
78:050-014
78:05G-015
78:050-016
78:050-033
78:05G-038
78:050-042
78:05G-049
78:06A-001
78:06A-004
78:06A-007
78:06A-013
78:06B-002
78:063-005
78:068-007
78:060002
78:060-002
78:06E-001
78:06G-003
78:07A-001
78:07A-002
78:078-011
78:078-017
78:078-022
78:088-004
78:100002
78:100005
Irrigation Canals
78:03F-042
78:056-011
78:078-027
Irrigation Design
78:03F-030
78:03F-042
78:03F-043
78:03F-088
78:03F-089
78:03F-093
78:03F-099
78:03F-100
78:03F-101
78:03F-102
78:03F-104
78:03F-109
78:03F-110
78:06A-013
78:06G-003
78:088-006
Irrigation Ditches
78:03F-042
78:03F-130
78:040-008
Irrigation Effects
78:021-001
78:021-006
78:021-040
78:03P-031
78:03F-062
78:03F-070
78:03F-096
78:03F-125
78:05G-020
78:060002
Irrigation Efficiency
78:03F-030
78:03F-034
78:03F-039
78:03F-042
78:03F-046
78:03F-047
78:03F-048
78:03F-053
78:03F-054
78:03F-058
78:03F-063
78:03F-064
78:03F-072
78:03F-077
78:03F-079
78:03F-080
78:03F-081
78:03F-083
78:03F-085
78:03F-096
78:03F-098
78:03F-099
78:03F-100
78:03F-104
78:03F-105
78:03F-106
78:03F-125
78:03F-127
78:048-014
78:068-005
Irrigation Operation
and Maintenance
78:03F-088
78:06A-013
78:080001
Irrigation Practices
78:03F-034
78:03F-035
78:03F-051
78:03F-052
78:03F-063
78:03F-067
78:03F-079
78:03F-096
78:03F-106
78:03F-125
78:03F-127
78:048-014
78:05G-016
78:05G-038
78:05G-039
78:06G-001
Irrigation Programs
78:03F-001
78:03F-046
78:03F-068
78:03F-086
322
-------
Irrigation Programs
(cont.)
78:03F-109
78:03F-116
78:06A-013
78:068-009
78:06G-001
78:10C-005
Irrigation Return Flow
78:05G-038
Irrigation Systems
78:021-034
78:03F-026
78:03F-032
78:03F-034
78:03F-041
78:03F-043
78:03F-044
78:03F-045
78:03F-046
78:03F-049
78:03F-050
78:03F-059
78:03F-061
78:03F-063
78:03F-064
78:03F-065
78:03F-078
78:03F-080
78:03F-081
78:03F-083
78:03F-084
78:03F-085
78:03F-086
78:03F-087
78:03F-088
78:03F-089
78:03F-090
78:03F-097
78:03F-098
78:03F-101
78:03F-102
78:03F-103
78:03F-115
78:03F-116
78:03F-U7
78:03F-118
78:05G-045
78:083-004
78:086-005
78:083-006
Irrigation Water
78:026-023
78:02G-045
78:02G-046
78:030-004
78:030-001
78:03F-012
78:03F-032
78:03F-033
78:03F-045
78:04A-003
78:053-048
78:05G-007
78:05G-038
78:060-002
Irrigation Wells
78:03F-047
Isotherms
* 78:02K-024
78:02K-030
78:02K-032
78:02K-035
78:02K-036
78:02K-060
78:02K-063
78:02K-070
78:058-028
Isotope Fractination
78:02F-026
Isotope Studies
78:02F-026
78:02K-011
78:02K-049
78:02K-057
78:073-006
Johnson Grass
78:02K-016
Judicial Decisions
78:06E-007
Kalman Filters
78:02A-006
78:083-011
Kansas
Kaolinite
Kentucky
78:03F-051
78:05G-063
78:02K-025
78:02K-035
78:02K-037
78:02K-063
78:03F-027
Kinematic Models
78:083-001
Kinetics
78:02G-056
78:021-013
78:02K-040
78:02K-065
Labor Savings
78:03F-096
Laboratory Equipment
78:02J-001
78:073-034
78:073-035
Laboratory Tests
78:02F-001
78:02F-027
78:020-007
78:02G-010
78:02G-012
78:02G-014
78:02G-016
78:02G-022
78:02G-024
78:02G-034
78:02G-040
78:02G-058
78:02G-062
78:020-066
78:026-081
78:02J-001
78:02J-002
78:02K-044
78:02K-064
78:02K-067
78:02K-074
78:02K-075
78:040-004
78:058-003
78:053-042
78:053-050
78:053-064
78:05G-038
78:073-016
78:073-024
78:073-034
78:073-035
78:08G-001
Lake Erie
78:05G-067
Lake Hefner
78:020-002
Lake Ontario
78:020-002
Lake-Water Budget
78:02F-015
Lakes
78:02F-015
78:053-041
Land Management
78:02J-012
78:02J-024
78:04A-012
78:050-024
78:05G-063
78:05G-067
78-.06E-021
Land Reclamation
78:02G-023
78:040-007
Land Resources
78:06E-021
Land Subsidence
78:06A-009
Land Use
78:02J-012
78:04A-012
78:040-005
78:05A-001
78:05A-010
323
-------
Land Use
(cont.)
78:05A-021
78:058-014
78:05G-003
78:05G-046
78:06A-014
78:06E-021
Landscaping
78:030-001
Latent Heat
78:02G-020
Lateral Conveyance
Structures
78:088-004
78:08B-006
Lea Valley
Leachate
Leaching
78:046-010
78:02G-005
78;02G-006
78:020-010
78:020-039
78:021-033
78:02K-015
78:02K-064
78:02K-067
78:02K-071
78:04A-016
78:05A-002
78:05B-003
78:05B-012
78:058-025
78:050-042
78:050-076
78:050-077
78:020-012
78:020-019
78:020-023
78:020-039
78:020-043
78:020-045
78:020-065
78:020-077
78:020-078
78:021-007
78:02K-018
78:02K-019
78:02K-041
78:02K-055
78:02K-071
78:03C-003
78:03C-004
78:03F-001
78:03F-005
78:03F-008
78:03F-010
78-.03F-015
78:03F-016
78:03F-044
78:03F-056
Lead
Leakage
78:03F-060
78:03F-096
78:03F-109
78:04A-016
78:05A-003
78:058-011
78:058-026
78:058-035
78:058-043
78:058-046
78:05G-002
78:050-021
78:050-036
78:050-042
78:050-044
78:02K-002
78:02F-003
78:02F-018
78:050-002
Leaky Aquifers
78:02F-003
Least Squares Method
78:048-013
78:05A-006
Leaves
78:021-038
78:040-004
78:078-007
Legal Aspects
78:03F-107
78:048-004
78:040-001
78:06E-005
78:06E-007
Legislation
78:050-047
78:050-048
78:06E-006
78:06E-009
Legumes
Lemons
Lettuce
Lime
78:021-011
78:078-006
78:03F-026
78:03F-063
78:058-013
Limiting Factors
78:03F-072
Linear Programming
78:03F-009
78:03F-101
78:04A-
78:04A-
78:04A-
78:050-
78:05G-
78:050-
78:06A-
78:06A-
78:068'
78:068
78:06E
•001
•003
•004
•003
•058
•075
-008
-016
•Oil
-012
-015
Linings
78:04A-018
78:080-001
Liquid Wastes
78:03F-059
Litter
Livestock
78:04D-004
78:05A-016
78:05A-019
Load Distribution
78:03F-069
Loam
78:020-061
78:020-079
78:02J-002
78:058-005
Local Government
78:06E-014
Loess
78:040-006
Lognormal Distributions
78:02E-002
London Basin (London)
78:048-010
Long Channels
78:02J-014
Longitudinal Dispersion
78:020-062
Louisiana
Low Flow
78:03F-089
78:046-005
78:03F-097
Low-Flow Augmentation
78-.03F-090
Lysimeters
78:02D-008
78:020-005
78:020-046
78:021-007
78:02K-044
324
-------
Lysimeters
(cont.)
Maryland
78:05G-062
78:02K-057
78:05A-003
78:05B-025
Magnesium
78:021-043
78:02K-003
78:02K-024
78:02K-035
78:02K-047
Magnesium Carbonate
78:02K-065
Maintenance
78:03F-050
78:05G-026
78:08A-001
Maintenance Costs
78:08A-002
Malathion
78:058-040
Malt Barley
78:03F-096
Management
78:03F-036
78:03F-062
78:056-064
78:05G-031
78:05G-047
78:05G-049
78:050-050
78:05G-059
78:05G-062
78:050-064
78:05G-069
78:05G-070
78:06A-010
78s06A-013
78:06B-001
78:068-002
78:068-014
78:06E-010
78:06E-011
78:06E-013
Manganese
78:026-037
78:02K-027
78:02K-052
78:02K-072
Mannings Equation
78:088-011
r
Mannings Formula
78:088-011
Marking
78:078-002
Markov Processes
78:02G-054
78:088-013
Mass Transfer
78:02E-003
78:02G-013
78:058-061
Materials
78:05G-026
Mathematical Models
78:02A-002
78:02A-007
78:02A-008
78:02A-009
78:020-001
78:020-005
78:02E-001
78:02E-004
78:02E-005
78:02E-008
78:02E-009
78:02F-003
78:02F-006
78:02F-007
78:02F-008
78:02F-009
78:02F-010
78:02F-012
78:02F-013
78:02F-014
78:02F-016
78:02F-018
78:02F-022
78:02F-028
78.-02G-001
78:02G-002
78:02G-003
78:02G-004
78:02G-006
78:020-007
78:02G-008
78:02G-009
78:020-013
78:020-018
78:02G-027
78:020-041
78:02G-042
78:02G-048
78:020-049
78:020-052
78:020-055
78:020-056
78:020-061
78:020-062
78:020-063
78:020-068
78:020-072
78:020-080
78:020-086
78:02J-013
78:02J-014
78:02J-017
78:02K-065
78:03F-009
78:03F-054
78:03F-099
78:03F-124
78:04A-002
78:04A-005
78:04A-007
78:04A-015
78:040-005
78:05A-006
78:05A-007
78:05A-020
78:058-009
78:058-010
78:058-014
78:05B-015
78:058-016
78:058-017
78:058-039
78:058-042
78:058-057
78:058-058
78:058-059
78:058-060
78:050-003
78:05G-030
78:050-031
78:050-066
78:06A-001
78:06A-002
78:06A-003
78:06A-010
78:068-017
78:06E-011
78:078-027
78:088-013
Mathematical Studies
78:02E-009
78:02F-004
78:02F-013
78:02F-024
78:02F-025
78:020-064
78:03F-013
78:088-001
78:088-007
Mathematics
78:020-001
78:02E-008
78:02J-014
Matric Potential Sensors
78:020-071
Meanders
78:050-030
Measurement
78:020-014
78:02G-075
78:02J-001
78:02K-061
78:03F-085
78:050-003
78:078-015
78:078-021
78:078-023
78:078-027
78:078-030
78:088-009
325
-------
Mechanical Properties
78-.02J-002
Melt Water
Mercury
78:02K-044
78:021-033
78:02K-Q33
78-.02K-055
78:05A-022
Metabolism
Metals
78:021-014
78:021-029
78:078-016
78:02K-064
Meteorological Data
78;02D-003
Meteorology
78:020-002
78:07B-015
Methodology
78:02E-007
78:02F-011
78:026-021
78:03D-001
78-.03F-095
78:05B-065
78:068-019
78:068-021
78:078-022
78:076-023
Mexican Water Treaty
78-.05G-022
78:06E-006
Michigan
78:021-043
78-.03F-073
78:05A-001
78:050-059
Micro Environment
78:021-020
Micro Organisms
78:02K-042
78:05B-019
78:058-050
Microdegradation
78:02K-033
78:02K-042
78.-05B-027
78:056-029
78:05B-056
78:076-016
Microwaves
Migration
78:076-034
78-.05B-034
Mine Wastes
78.-02J-009
78:02K-031
Mineralization
78:058-018
Minerology
Mining
78:021-043
78:02J-003
78-.02K-050
78:02J-009
78:02J-010
Minnesota
78-.05A-004
Mississippi
78:05G-043
Missouri
78:02J-007
78:04D-006
78:056-008
Missouri River
78:056-015
Mixing
78:05B-011
78-.05B-013
78:05B-015
Model Calibration
78:020-063
Model Studies
78-.02A-002
78-.02A-003
78:02A-004
78.-02A-005
78:02A-010
78:02A-011
78:02C-001
78:020-001
78:02D-007
78:020-008
78:02E-001
78.-02E-002
78:02E-003
78:02E-004
78:02E-007
78-.02E-008
78:02E-009
78-.02E-010
78:02P-001
78:02P-003
78-.02F-008
78:02F-010
78:02F-011
78:02F-012
78:02F-013
78:02F-014
78:02F-015
78:02F-016
78:02F-022
78s02G-001
78-.02G-002
78:02G-003
326
78:02G-
78:02G-
78:02G-
78:02G-
78:02G-
78:02G-
78:02G
78:02G
78:02G
78:02G-
78-.02G-
78:02G-
78:02G-
78:02G-
78:02G-
78:021-
78:02J-
78-.02J-
78-.02J-
78:02J-
78:02J-
78.-02J-
78:036-
78:03F-
78:03F-
78-.03F-
78:03F-
78:04A-
78:04B-
78:048-
78:048-
78:04B-
78:040-
78:05B-
78:058-
78:058-
78:05B-
78:053-
78:05B-
78-.05B-
78:05B-
78:058-
78:058-
78:056-
78:056-
78:050
78:05G'
78:05G-
78:05G-
78:05G-
78.-06A'
78:06A'
78:06A
78:06A
78.-06A
78:066'
78:068
78:066
78:066
78:066
78:066
76:06B
78:06E
78:08B
78;08B
78:08B
78:088
006
007
008
009
013
016
027
041
052
054
055
060
063
080
081
004
010
013
014
015
019
024
001
•054
056
123
•124
•005
•002
•007
•Oil
•012
•005
•010
•013
•014
•015
-016
-017
-018
•039
-042
•057
•058
•061
-007
-065
-067
-072
-075
-002
-008
-009
-010
-015
•016
-009
-012
-015
-017
-019
-020
021
-015
-001
-004
-Oil
-013
Mohave Valley (Arizona)
78:040-007
-------
Moisture
78:07B-034
Moisture Availability
78:03F-055
78:07B-017
78:07B-036
Moisture Content
78:02G-001
78:02G-002
78:02G-006
78:020-016
78:020-027
78:020-028
78:020-030
78:020-040
78:020-048
78:020-061
78:020-066
78:020-067
78:020-075
78:020-076
78:020-080
78:020-084
78:020-085
78:021-020
78:021-028
78:02K-038
78:03F-033
78:03F-039
78:03F-055
78:05A-022
78:078-017
78:07B-022
78:078-034
Moisture Deficit
78:02A-008
78:020-038
78:020-076
78:021-018
78:021-019
78:021-025
78:021-028
78:021-029
78:021-034
78:021-036
78:021-038
78:021-040
78:021-041
78:021-042
78:030005
78:03F-021
78:03F-022
78:03F-048
78:03F-051
78:03F-100
Moisture Meters
78:020-016
78:03F-033
Moisture Stress
78:021-006
78:021-018
78:021-019
78:021-025
78:021-028
78:021-034
78:021-036
78:021-038
78:021-041
78:021-042
78:030002
78:03F-021
78:03F-022
78:03F-031
78:03F-062
Moisture Tension
78:020-029
78:020-073
78:020-076
78:020-084
78:021-008
78:021-011
78:021-019
78:021-020
78:021-038
78:03F-039
78:03F-118
78:078-017
Moisture Uptake
78:021-008
78:021-013
78:021-023
Molybdenum
78:02K-051
Momentum Equation
78:020-053
78:04A-007
Mulching
Monitoring
Monocots
Montana
78:03F-014
78:05A-007
78:05A-008
78:078-005
78:02K-033
78:078-007
Monte Carlo Method
78:02E-001
78:02E-009
78:02F-007
Montmorillonite
78.-02K-012
78:02K-025
Moody Resistance Diagram
78:088-005
78:088-010
Mosquitoes
Movement
78:060-001
78:02K-016
78:02K-017
78:03F-055
78:040-004
Multiple Purpose
Reservoirs
78:04A-004
Multi-Regression
Equations
78:020-002
Municipal Wastes
78:050007
Natural Gas
78:03F-038
78:03F-067
Nebraska
78:03F-046
78:03F-051
78:03F-060
78:03F-083
78:03F-086
78:03F-106
78:04A-009
78:04A-016
78:05A-010
78:05G-076
Net Profit
78:068-009
Network Design
78:02F-023
78:05A-007
Networks
78:05A-007
78:068-003
Neutron Activation
Analysis
78:078-009
Nevada
New York
78:058-002
78:058-016
New Hampshire
78:020001
New Mexico
New York
Moving Boundaries
78:02F-004
Nickel
Nitrogen
78:03F-038
78:02K-034
78:056-060
78:050-068
78:068-017
78:021-032
78:02K-061
327
-------
Nitrates
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
:02G-035
:02G-036
:02G-050
:02I-014
-•021-028
.-02K-004
:02K-005
:02K-009
:02K-018
.•02K-020
:02K-048
:02K-057
:02K-067
:02K-068
:02K-071
:03F-001
:03F-005
:03F-012
:03F-015
.-03F-016
:03F-056
:03F-057
:03F-060
:04A-016
:05A-004
:05A-005
:05A-009
:05A-021
:05B-001
:05B-011
:05B-020
:05B-021
:05B-025
:05B-039
:05B-043
:05B-047
:05B-054
:05B-064
:05D-001
.-05G-002
:OSG-018
:05G-021
:05G-034
J05G-037
•-05G-045
:05G-073
:05G-074
:05G-076
:056-077
:07B-008
: 078-023
:10A-001
Nitrites
78.-02K-049
78:05A-005
78:05A-009
78:05B-054
78:07B-008
Nitrogen
Nitrification
78:02K-017
78:02K-018
78t02K-022
78i03F-004
78:03F-005
78:03F-029
78:05A-005
78:05A-021
78:053-018
78:058-047
78:058-054
78:050-002
78:056-045
78:07B-002
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78:
78;
78;
78;
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78
78:
78;
78;
78:
78i
78:
78:
78;
78:
78:
78:
78:
78:
78:
78:
323
:02A-001
:02A-004
.-02F-002
:02G-032
:02G-035
:02G-036
:02G-051
:02I-007
: 021-016
:02I-026
:02I-028
:02I-029
:02I-030
:02K-001
:02K-004
:02K-009
:02K-019
:02K-022
r02K-029
:02K-038
:02K-040
:02K-043
:02K-048
:02K-057
02K-066
02K-067
02K-068
02K-071
02K-074
02K-075
03F-001
:03F-002
.-03F-003
:03F-004
:03F-005
:03F-010
:03F-012
.•03F-013
:03F-014
:03F-015
:03F-01€
:03F-017
:03F-018
:03F-019
:03F-022
:03F-023
:03F-028
:03F-029
J03F-056
:03F-057
:03F-060
:03F-073
:04A-016
:05A-020
:05A-021
058-006
058-008
058-011
058-018
058-020
058-040
058-041
058-044
78:058-046
78:058-047
78:05B-064
78-.05B-067
78:05C-003
78:05G-005
78:05G-007
78:05G-008
78:05G-021
78:05G-034
78:05G-037
78.-05G-043
78:05G-045
78:050-074
78:050-076
78:05G-077
78:06A-008
78:06B-020
78:076-010
78:078-013
78:078-024
78:10A-001
Nitrogen Compounds
78:03F-057
78:05A-009
78:05G-008
78:05G-037
78:07B-002
Nitrogen Cycle
78:02K-057
78:02K-061
78:058-025
78:058-064
78.-05G-008
78:068-020
78:10A-001
Nitrogen Fixation
78:02G-026
78:021-009
78:03F-060
78:050-003
78:056-007
78.-05G-008
78:078-006
Nitrogen Removal
78:058-043
Noise Covariances
78:02A-006
Nonlinear Programming
78:04A-004
78:05G-031
Nonpoint Pollution Sources
78:058-067
Nonuniform Flow
78:026-009
North Carolina
78:02K-069
78:03F-074
78:03F-075
78:056-034
78:06E-009
-------
North Dakota
78:02G-079
Nutrients
Nozzles
78:03F-058
78:03F-072
78:03P-103
Nuclear Energy
78:03F-067
78:063-004
Numerical Analysis
78:02F-004
78:02F-006
78:02F-015
78:02F-017
78:02F-020
78:02F-024
78:02G-015
78:02G-027
78:02G-048
78:020-049
78:02G-050
78:02G-060
78:02H-002
78:02J-017
78:04A-002
78:048-002
78:06A-004
78:06A-005
78:06A-009
Nutrient Removal
78:02A-004
78:021-017
78:021-043
78:02K-004
78:02K-019
78:02K-027
78:02K-060
78:02K-072
78:03F-010
78:03F-018
78:03F-027
78:03F-060
78:04A-013
78:05A-004
78:05A-016
78:05A-018
78:05A-020
78:05B-008
78:058-037
78:058-046
78:058-049
78:058-064
78:058-068
78:05G-029
78:056-070
78:05G-072
78:068-017
Nutrient Requirements
78:021-027
78:021-030
78:03F-006
78:03F-023
78:03F-061
78:05G-070
78:078-004
78:078-013
Oats
Ohio
Oil
78:02G-032
78:02G-033
78:020-051
78:021-007
78:021-019
78:021-043
78:02K-045
78:02K-072
78:03F-008
78:03F-019
78:03F-061
78:05A-012
78:05A-017
78:058-041
78:058-049
78:058-067
78:05G-029
78:05G-030
78:050-037
78:05G-043
78:078-010
78:078-012
78:078-013
78:078-019
78:021-043
78:02K-016
78:03F-027
78:02K-011
78:058-007
78:058-025
78:03F-067
78:068-004
Oil Shales
Oklahoma
78:068-004
78:050-037
Ombone River Basin
78:02A-006
On-Site Data Collections
78:058-041
On-Site Investigations
78:02K-044
78:048-010
78:04D-002
78:058-002
78:058-041
78:05G-038
Onions
78:021-021
Open Channel Flow
78:02J-016
78:078-011
78:088-002
78:088-011
329
Open Channel Hydraulics
78:088-011
Open Channels
78:02J-013
78:058-061
78:088-001
78:088-002
78:088-008
78:088-011
Operating Rules
78:04A-004
Operation and Maintenance
78:03F-038
Operations Research
78:06A-010
Optimization
78:02A-002
78:02F-011
78:03F-009
78:03F-092
78:03F-101
78:04A-001
78:04A-003
78:04A-004
78:058-009
78:050-003
78:05G-010
78:050-031
78:06A-008
Optimum Development Plans
78:050-004
Oranges
Oregon
78:03F-065
78:050-044
78:06A-007
Organic Acids
78:021-014
Organic Compounds
78:02K-014
78:02K-021
Organic Material
78:02K-006
78:02K-027
78:050-001
Organic Matter
78:02F-002
78:020-037
78:021-005
78:021-033
78:02K-026
78:02K-050
78:02K-051
78:02K-058
78:02K-074
78:02K-075
78:03F-023
-------
Organic Matter
(cont.)
78:03F-060
78:03F-113
78:078-018
Organic Soils
78:020-030
78:02K-067
78:02K-070
78:058-046
78:05G-002
Organic Wastes
78:050-042
Organophosphorus Compounds
78:02K-049
78:02K-053
Ozone
Pans
Paraquat
78:07B-023
78:021-003
78:05B-028
Peppers
78:058-040
Orificies
Orthogonal
78:03F-032
78:088-009
78:020-061
Osmotic Pressure
78:021-031
78:021-038
78:030-004
78:03F-005
78:078-017
Overburden
78:020-047
Overirrigation
78:03F-096
Overland Flow
78:02E-010
78:02J-005
78:02J-018
78:05B-012
78:058-036
78:058-038
Oxidation-Reduction
Potential
78:02K-068
78:058-047
78:058-056
78:05G-074
78:078-020
Oxidation
Oxygen
78:02K-031
78:02K-052
78:02K-074
78:02K-075
78:058-002
78:021-002
78:02K-052
78:078-030
78:078-035
Particle Size
78:02G-079
78:02J-027
78:02K-003
78:02K-019
78:02K-041
78:040-002
78:058-028
Partitioning Procedure
78:050-031
Pasture Management
78:050-051
Pastures
78:04A-012
Path of Pollutants
78:05A-001
78:058-003
78:058-013
78:058-014
78:058-016
78:058-057
78:058-058
78:058-062
Pathogenic Bacteria
78:058-050
Pattern Recognition
78:02E-007
Peaches
78:03F-061
78:03F-075
Peak Discharge
78:04A-015
Peak Loads
Peanuts
Peat
78:03F-069
78:02K-041
78:02G-026
78:02K-006
Penetration
78:02G-021
Pennsylvania
78:05A-003
78:068-011
78:060-002
Perched Water
78:058-052
78:05G-025
78:078-036
Percolating Water
78:02G-019
78:058-040
Percolation
78:020-005
78:02G-009
78:056-040
Performance
78:03F-091
78:03F-097
78:03F-098
Permeability
78:02F-017
78:02G-023
78:04A-018
78:048-003
Persistence
78:02K-016
78:058-026
78:058-027
78:058-033
78:058-035
78:058-050
78:058-056
Pesticides
78:02K-062
78:03F-036
78:03F-067
78:040-003
78:05A-003
78:058-024
78:058-027
78:05B-028
78:058-029
78:058-030
78:058-031
78:058-032
78:058-033
78:058-034
78:058-035
78:058-036
78:058-040
78:058-056
78:050-002
78:05G-073
78:06A-002
78:06A-003
78:06G-002
78:078-016
78:OiOC-003
Pesticide Kinetics
78:026-056
78:058-030
78:058-032
78:078-016
330
-------
Pesticide Residues
78:05B-023
78:05B-027
78:058-033
78:058-034
78:058-035
78:058-036
78:058-056
78:050-072
78:078-016
Phosphate Transport
78:05A-011
Phosphates
78:021-022
78:02K-004
78:02K-012
78:02K-032
78:02K-037
78:02K-063
78:03F-025
78:05A-011
78:058-007
78:058-008
78:05G-030
78:078-008
Phosphorus
78:02G-032
78:021-005
78:021-009
78:021-012
78:02K-014
78:02K-021
78:02K-036
78:02K-039
78:02K-045
78.-02K-051
78:02K-060
78:02K-069
78:02K-072
78:03F-003
78:03F-025
78:05A-016
78:05A-017
78:05A-019
78:05A-020
78:058-003
78:058-040
78:05B-041
78:058-044
78:05B-046
78:05C-007
78:05G-030
78:05G-037
78:05G-043
78:06A-008
78:078-010
78:07B-014
78:078-019
Phosphorus Compounds
78:02G-033
78:02K-014
78:05A-011
78:05B-007
78:058-008
Photosynthesis
78:021-018
78:05C-003
78:050005
Physical Properties
78:02J-003
Piezometers
78:078-025
Pipe Flow
Pipelines
78:088-005
78:088-010
78:03F-053
78:03F-088
78:08A-001
78:088-005
78:088-006
Pipes
78:08A-001
78:088-003
78:088-008
78:08G-002
78:08G-003
Pit Recharge
78:02F-001
78:048-003
Plankton
Planning
78:05G-030
78:058-009
78:05G-004
78:050-050
78:05G-060
78:050-061
78:05G-062
78:06A-010
78:06A-014
78:06E-004
78:06E-009
78:06E-013
78:06E-014
78:06G-002
Plant Breeding
78:03C-001
Plant Growth
78:021-001
78:021-019
78:021-027
78:021-035
78:021-043
78:02K-004
78:02K-072
78:03C-002
78:03F-021
78:03F-025
78:078-007
Plant Nutrition
78:02K-033
Plant Physiology
78:021-019
78:03C-001
Plant Population
78:021-040
Planting Management
78:03F-002
78:03F-124
Plastic Pipes
78:088-010
78:08G-002
78:080-003
Platte River (Nebraska)
78:05A-010
Playas
78:06E-003
Pleistocene Epoch
78:02K-006
Plutonium
Podzols
78:040-001
78:040-002
78:02K-015
Political Aspects
78:06G-002
Pollen
78:058-041
Pollutant Identification
78:05A-019
78:05A-022
78:058-020
78:05G-005
78:05G-051
Pollutants
78:02A-004
78:02K-002
78:02K-022
78:02K-032
78:02K-049
78:03F-019
78:04A-013
78:05A-001
78:05A-002
78:05A-005
78:05A-007
78:05A-022
78:058-006
78:058-010
78:058-028
78:058-030
78:058-031
78:058-032
78:058-034
78:058-037
78:058-039
78:058-055
78:058-057
78:058-058
331
-------
Pollutants
(cont.)
78:058-067
78:050002
78:050-001
78:05G-021
78:05G-037
78:050-063
78:06A-003
78:06A-016
78:06B-021
Pollution Abatement
78:02A-014
78:02J-006
78:03C-003
78:03F-011
78:04A-009
78:05B-006
78:058-032
78:056-005
78:05G-021
78:05G-024
78:056-051
78:05G-061
78:056-069
78:06A-003
78:06A-016
78:06E-005
Ponding
Ponds
78:026-052
78:026-055
78:026-072
78:056-038
Pore Pressure
78:026-018
78:026-034
78:026-057
78:026-080
78:048-003
Pore Water
78:02F-027
78:026-034
78:048-003
Porosity
78:026-024
78:026-042
78:026-057
78:026-081
78:048-009
Porous Media
78:02F-001
78:02F-004
78:02F-006
78:02F-009
78:02F-013
78:02F-020
78:02F-023
78:02F~025
78:026-018
78:026-042
78:026-061
78:026-063
78:026-064
78:026-068
78:048-002
78:06A-009
78:088-012
Potassium
78:026-032
78:021-007
78:021-014
78:021-017
78:021-021
78:021-023
78:02K-004
78:02K-026
78:02K-035
78:02K-060
78:02K-070
78:03F-003
78:078-004
78:078-010
Potassium Nitrate
78:058-040
Potatoes
78:03F-005
78:03F-036
78:03F-063
78:03F-070
78:058-043
Potentiometric Level
78:048-013
Powerplants
78:048-001
78:058-015
Precipitation
78:02A-007
Precipitation (Atmospheric)
78:02A-005
78:02A-008
78:028-001
78:026-052
78:02J-004
78:03F-123
78:05A-012
78:058-006
78:058-023
78:058-041
78:078-015
78:078-028
Precipitation Excess
78:02A-005
78:026-052
Prediction
78:06A-001
78:060-001
Preservation
78:078-008
Pressure Conduits
78:088-006
Pressure Head
78:026-003
78:026-048
78:026-064
78:03F-072
78:03F-076
78:03F-087
78:03F-110
78:03F-127
78:078-025
Pricing
78:056-016
78:10C-005
Probability
78:028-001
78:02E-001
78:02E-002
78:026-074
78:05A-006
Production Function
78:03F-009
Productivity
78:021-009
78:03F-003
78:03F-070
78:03F-089
Profiles
Profit
Programs
78:026-047
78:03F-009
78:03F-096
78:03F-107
78:056-063
78:06E-013
78:06E-020
Project Evaluation
78:100005
Project Planning
78:06A-013
Projection
78:04A-008
Projects
78:04A-003
Pressure
78:026-024
78:026-080
Properties
78:05A-015
Public Health
78:058-004
Pump Testing
78:03F-038
78:03F-082
332
-------
Pumping
78:02F-003
7B-.02F-012
78:02F-018
78:02F-027
78:048-014
78:08C-001
Pumping Plants
78:03F-038
78:03F-066
78-.03F-082
Pumps
Pyrite
Quartz
78-.03F-038
78:03F-066
78:03F-082
78:02K-031
78:02K-007
Radiation
78:020-006
78:02F-021
78:03F-007
78:03F-026
Radioactive Wastes
78:05B-042
Radioactivity
78:05B-042
78:050-001
Radiochemical Analysis
78:078-009
Radioisotopes
78:02G-040
78:021-009
78:02K-062
78:04D-002
Rain
78:058-041
Rain Gages
Raindrops
78:078-015
78:07B-028
78:02J-018
Rainfall
78:028-001
78:Q2E-011
7i8:02G-052
78:02G-055
78:02G-058
78:020-072
78:02K-023
78:04A-017
78:04D~005
78:05A-012
78:058-006
78:058-023
78:058-027
78:05G-037
78:06A-006
78:078-015
78-.07B-028
Rainfall Intensity
78:02A-009
78:02G-052
78:02J-018
78-.02J-025
78:04A-017
Rainfall-Runoff
Relationships
78:02A-006
78:02A-009
78:058-023
Range Grasses
78:078-006
Range Management
78:05G-051
78:07B-006
Ranges
78:04A-006
78:058-012
Rates of Application
78-.02G-032
78:02G-033
78:02K-018
78-.03F-023
Recession Curves
78:03F-054
78:03F-099
78:03F-100
Recharge Wells
78:048-010
Reclamation
78-.02G-065
78:03F-006
78:05G-036
Reduction (Chemical)
78:021-014
78:02K-029
78:02K-048
78:02K-052
78:02K-068
Regional Analysis
78t05G-035
Regression Analysis
78-.02A-001
78:02E-001
78:021-005
78:02J-009
78:02J-022
78:02K-050
78:03F-062
78:03F-105
78:03F-126
78:05B-001
78:058-036
333
78:05G-036
78.-05G-046
78:078-004
Remote Sensing
78-.02F-021
78:02G-031
78:03F-112
78:060-001
78:078-025
Rental Market
78:05G-033
Repairing
78:08A-001
Rescaled Adjusted Range
78.-02E-004
78:02E-008
78:02E-009
Research and Development
78-.02J-011
78:10C-002
Reservoir Design
78s04A-004
Reservoir Leakage
78:08G-00]
Reservoir Operation
78:02H-001
78:04A-001
78-.04A-003
78:04A-004
Reservoir Releases
78.-02H-001
Reservoir Storage
78:04A-008
Reservoirs
78:020-004
78:02H-001
78:02H-002
78:04A-008
78:04A-018
78:088-013
Resistence Coefficient
78:088-011
Resource Allocation
78-.03F-009
78s05G-035
Respiration
78s05C-006
Response Function
78J03F-095
Retardance
78:02E-010
Retention
78:02G-079
78:02G-084
-------
Return Flow
78:
78:
78:
78
78
78
78
78
78
78
78
78
76
78
78
78
78
78
78
78
78
78
78
78
River Beds
02J-015
03F-014
03F-085
:05A-002
:05A-018
:05B-002
:05B-006
:05B-037
:05B-056
-.05G-020
:05G-022
:05G-033
:05G-039
:05G-044
:05G-045
:05G-073
.-OSG-074
.-05G-075
:05G-077
:06B-001
:07A-002
.•lOC-001
:10C-002
:10C-006
78-.08B-001
River Flow
Re turn (Monetary)
78:06C-001
Revegetation
78:050-001
Reviews
78:03F-112
78.-04A-006
78:068-021
78:100-003
Reynolds Number
78:08B-010
Rice
78:02G-C32
78:02G-051
78:021-037
78:02K-001
78:02K-040
78:02K-065
78.-03F-006
78:03F-062
78:056-056
78:05G-039
78t06A-006
Rill Erosion
78:02J-021
Risks
78:03F-087
River Basin
78-.05A-008
78-.05G-035
River Basin Management
78:05G-016
78.-02E-003
78:02E-008
78:05A-008
78:088-013
Rivers
78:058-010
78:05B-013
78-.05B-015
78:05B-042
78:08B-013
River Systems
78-.05G-031
78:05G-033
Root Development
78:021-023
78:02K-004
78:03C-002
78:078-005
Root Distribution
78:021-008
Root Systems
78:021-004
78:021-012
78:021-013
78:021-021
78:021-023
78:038-001
Root Zone
78i02G-021
78:02G-076
78.-03F-013
78:058-040
78:073-019
Roughness Coefficient
78:02J-022
Roughness (Hydraulic)
78:02E-010
78:02J-016
Routing
Runoff
78:06A-008
78:02E-011
78.-02G-005
78:020-021
78:02G-052
78:02G-058
78:02-1-037
73:02J-010
78:02J-012
7B:02J-018
78:02J-027
78-.02K-032
78:03F-054
78:03F-070
78-.03F-072
78-.03F-081
78:03F-099
78:03F-123
78:04A-006
78:04A-009
78.-04A-010
78:04A-012
78.-04A-013
78.-04A-017
78:05A-002
78:05A-017
78:05A-018
78:05B-003
78 :05B-006
78:058-014
78:053-025
78:050-029
78:056-031
78:05B-032
78:05B-036
78:056-037
78:056-046
78.-05G-029
78:05G-038
78:05G-043
78:05G-059
78:06A-008
78:06E-003
78:07B-032
78:10C-003
Saint Venant Equation
78:Q8B-001
Salaquifers
78-.04B-013
Saline Soils
78.-02G-014
78:02G-071
78:03C-002
78:03C-004
78:030-005
78:053-038
78:05G-009
78s05G-011
78-.05G-028
•78;07A-003
Saline Water
78:02G-045
78-.02G-046
78:021-002
78:021-025
78:030-002
78:030-003
78:030-004
78:030-006
78:050-001
78:056-016
78:05G-023
78:056-028
78:07A-003
334
-------
Saline Water Intrusion
;78j02F-008
Saline Water-Freshwater
Interfaces
78:02F-008
Salton Sea (California)
78:04B-001
Salinity
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78;
78;
78s
78:
78
78
78
78
78
78
78
78
78
78
02G-014
02G-G39
:02G-071
-.021-024
:02I-025
:02I-028
:02I-029
:03C-002
:03C-003
:03C-004
:03C-005
:03C-006
:03F-040
:04B-006
:05B-022
:05B-038
:05G-009
:05G-010
:05G-011
t05G-019
:05G-020
:05G-022
t05G-023
:05G-025
:05G-028
:05G-035
:05G-044
:05G-050
:05G-073
:05G-075
:06B-002
:06E-00€
:06G-003
-.07A-003
.-10C-001
Salinity Measurements
78:020-071
Salinity Meter
78:02G-071
Salinity Sensor
78:02G-071
Salt Balance
78:02G-039
78:030006
78:058-038
78:05G-073
Salt Tolerance
78:021-015
78j03C-001
78s03C-005
Salt Water
78:05G-011
Saltation
Salts
78:02G~004
78:02G-010
78:02G-012
78:02K-015
78:03C-004
78:05B-012
78:05B-038
78-.05G-028
78:05G-038
Sampling
78:02K-Q66
78:040-001
78:05A-001
78:05A-007
78:05A-008
78:05A-011
78:05A-015
78:05B-042
78:07A-003
78:078-001
78:076-002
78-.07B-005
78:078-028
78:07B-034
San Luis River Basin
(California)
78:050-016
Sands
78:020-002
78:02G-022
78-.02G-062
78:02J-005
78:04A-018
78s04B-010
78s05B-005
Saprolites
78:02K-007
Saskatchewan River
78:02E-007
Saturated Flow
78.-02C-001
78s02F-006
78:02F-013
78:02F-028
78:02G-019
78:020-047
78:020-048
78:04B-011
78:04B-012
78:05B-019
78-.06A-009
Saturated Soils
78:020-024
Scaling
78:020-043
78:02J-017
78:050-001
Scheduling
78:020-
78:021-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:03F-
78:04A-
78s07A-
•008
•038
•033
•046
•049
•052
•068
•073
•077
•112
-016
-001
Scour
78:02J-016
Seasonal
78:02H-002
78:02K-056
78-.04A-008
78:020-007
Sediment
78:05G-073
Sediment Control
78:02J-006
78j02J-007
78:02J-008
78:02J-009
78:02J-010
78-.02J-022
78:02J-028
78:04A-009
78:04A-013
78-.05G-003
78:05G-038
78:05G-048
78:05G-058
78:05G-060
78:06A-016
78:06B-011
78-.06B-015
78:06E-015
78:08A-004
Sediment Discharge
78:02J-004
78:02J-008
78:058-065
78:Q5B-068
78:05G-019
78:056-064
78:050-065
78:06A-016
Sediment Distributions
78-.02J-014
78:02J-025
78:07A-002
Sediment Load
78:02J-003
78:02J-007
78.-02J-008
78-.02J-010
78:02J-015
78:05B-068
78:050-063
78:050-072
78:06E-015
78:07A-002
335
-------
Sediment Sorting
78:04D-002
Sediment Sources
78:02J-013
Sediment Transport
78:02J-005
78:02J-013
78:02J-014
78:02J-017
78:02J-019
78:02J-022
78:02J-024
78:040-001
78:04D-002
78:058-068
Sediment Yield
78:02J-005
78:02J-010
78:02J-012
78:02J-019
78:02J-022
78:050-037
78:06A-008
78:06A-015
78:06E-015
78:08A-004
Sedimentation
78:02J-014
78:02J-024
78:02J-026
78:04C-001
78:040-006
78:05A-020
78:05G-058
78:088-013
Sedimentation Rates
78:040-005
Sediments
Seeds
78:02J-007
78:02J-008
78:02J-009
78:02J-010
78:02J-013
78:02J-014
78:02J-015
78:02J-025
78:040-001
78:040-002
78:040-004
78:040-005
78:040-008
78:058-003
78:056-008
78:058-028
78:058-042
78:058-044
78:050-037
78:050-038
78:088-003
78:020-029
78:021-009
78:021-011
Seepage
78:02F-008
78:02F-014
78:02F-015
78:02F-019
78:03F-081
78:04A-002
78:04A-018
78:058-022
78:050-011
78:06A-005
78:080-001
Seepage Control
78:02F-019
78:04A-018
78:06A-005
78:080-001
Selectivity
78:021-021
78:02K-035
78:02K-070
Self Purification
78:058-034
Semiarid Climates
78:038-001
78:03F-041
78:04A-009
78:06E-003
Sensitivity Analysis
78:02A-003
Sensitivity Coefficient
78:02A-003
Septic Tanks
78:058-004
78s05B-052
Shales
78:058-038
Sevin
Sewage
78:058-040
78:05C-006
Sewage Bacteria
78:058-004
Sewage Disposal
78:021-033
78:02K-055
78:058-052
78:050-007
Sewage Effluent
78:021-033
78.-02K-055
78:058-019
78:058-052
78:050-007
Sewage Slude
78:021-010
78:021-032
Shallow Water
78:02F-021
78:020-076
Shear Strength
78:02J-002
Sheet Erosion
78:02J-021
Sheet Flow
Silage
Silting
Silts
78:02E-010
78:03F-027
78:02J-026
78:020-061
78:03F-035
78:058-005
Simulated Analysis
78:050-018
78:050-064
78:050-072
Simulated Rainfall
78:02E-011
78:020-066
78:02J-025
78:02J-027
78:040-004
78:050-029
Simulation Analysis
78:02A-002
78:02A-004
78:02A-006
78:02A-011
78:02E-008
78:02F-011
78:02F-015
78:020-015
78:020-060
78:021-004
78:021-012
78:021-020
78:02J-005
78:02J-009
78:02J-012
78:02J-017
78:02J-019
78:02J-024
78:02K-005
78:038-001
78:03F-058
78:048-007
78:048-008
78:058-018
78:06A-003
78:06A-006
78:06A-014
78:06A-015
336
-------
Simulation Analysis
(cont.)
78:06B-020
78:060-001
78:088-004
Simulation
Sink
Sites
Size
Skimming
Slime
78:06A-001
78:021-008
78:03F-023
78:02J-025
78:04D-008
78:08A-004
78:03F-090
Slope Stability
78:04A-010
78:04D-006
78:04D-008
Slopes
78:02F-010
78:02F-014
78:02J-005
78:04A-010
78:040-008
78:06A-004
Small Watersheds
78:02A-010
78:02E-011
78:02J-004
78:04A-015
78:05A-021
78:05G-024
78:06A-003
Snow
Snowmelt
78:02K-044
78:058-041
78:02K-044
78:058-044
78:068-017
Snowpacks
78:02K-044
Social Aspects
78:03F-079
78:03F-107
78:05G-047
78:05G-055
78:068-010
78:06G-002
78:060-003
Social Impact
78:03F-079
78:06A-007
78:06B-010
78:06C-002
Social Participation
78:03F-079
78:050-055
Sodium
78:020-004
78:020-023
78:02K-024
78:02K-047
78:02K-058
78:050-036
Sodium Adsorption Ratio
78:02J-002
Sodium Chloride"
78:021-002
78:058-005
Sodium Compounds
78:02K-003
78:078-010
Soil Aggregates
78:02J-027
Soil Amendments
78:021-010
78:02K-031
78:02K-033
78:050-036 '
Soil Analysis
78:020-023
78:02K-021
78:02K-045
78:02K-055
78:02K-064
78:02K-069
78:05A-011
78:078-010
78:078-019
Soil Bacteria
78:05A-021
Soil Chemical Properties
78:020-023
78:020-030
78:02G-037
78:021-024
78:02K-017
78:02K-028
78:02K-051
78:02K-066
78:02K-069
78:02K-070
78:07A-003
78:078-004
78:078-010
78:078-014
Soil Chemistry
78:020-005
78:020-019
78:020-037
78:02K-008
78:02K-009
78:02K-010
78:02K-013
78:02K-014
78:02K-021
78:02K-023
78:02K-028
78:02K-030
78:02K-034
78:02K-036
78:02K-039
78:02K-059
78:02K-062
78:02K-063
78:02K-065
78:02K-066
78:02K-068
78:02K-070
78:02K-073
78:02K-074
78:02K-075
78:06A-001
Soil Classification
78:03F-070
Soil Compaction
78:078-022
Soil Conservation
78:02E-011
78:02J-001
78:02J-006
78:04A-010
78:04C-001
78:05G-024
78:050-048
78:050-049
78:050-060
78:050-061
78:05G-065
78:05G-068
78:068-002
78:068-011
78:068-014
78:06E-005
78:06E-011
78:06E-015
Soil Contamination
78:02K-011
78:05A-003
78:05A-022
78:058-004
78:058-024
78:058-026
78:058-039
78:058-055
78:058-057
78:058-058
78:050-001
Soil Disposal Fields
78:058-004
Soil Drainage
78:050-034
337
-------
Soil Environment
78:02K-056
78:05A-009
Soil Erosion
78
78
78
78:
78:
78;
78;
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
:02A-010
:02J-004
:02J-007
:02J-008
:02J-012
:02J-015
:02J-018
:02J-020
:02J-021
:02J-024
:02J~025
:02J-026
:02J-027
:03F-070
:03P-072
:03F-113
:04A-017
:04C-001
:04D-001
:04D-004
:04D-007
:05B-003
:05B-007
:05B-008
:05B-065
:05G-037
:05G-043
:05G-058
(05G-059
06B-014
06B-015
06E-002
08A-004
Soil Formation
78:02K-007
Soil Gases
78:02K-056
78:02K-057
78:02K-061
78:078-030
78:07B-035
Soil Horizons
78:02G-028
78:020-040
78:02K-050
78.-07B-036
Soil Investigations
78:03F-029
Soil Management
78:02G-023
78:02G-030
78:02J-020
78:02K-039
78:03F-018
78:03F-108
78:040-007
78.-05A-009
Soil Microbiology
78:02K-042
78:050-002
Soil Moisture
78:02A-009
78:020-007
78:02G-018
78:02G-031
78:02G-038
78:02G-040
78:02G-052
78.-02G-063
78:02G-071
78:02G-073
78:02G-074
78:02G-075
78:02G-084
78:02G-085
78:021-041
78:02K-005
78:02K-061
78:033-001
78-.03F-025
78:03F-028
78:03F-033
78:03F-039
78.-03F-095
78.-03F-112
78:03F-118
78:05A-009
78:068-005
78:060-002
78:078-017
78:076-034
Soil Moisture Movement
78:02A-007
78:02D-005
Soil Moisture Sensor
78:02G-071
Soil Morphology
78:04D-006
Soil Physical Properties
78:02G-019
78:02G-030
78:02G-034
78:02G-037
78:02G-060
78:02G-073
78:02K-017
78;02K-020
78:03F-070
Soil Physics
78:02G-053
78:02G-054
Soil Profiles
78-.Q2G-050
78:020-057
78:021-008
78-.02K-003
78:02K-035
Soil Properties
78:02A-009
78:020-005
78:02F-002
78.-02G-057
78:02G-068
78:02G-074
78:02G-081
78:021-003
78:021-005
78:021-012
78:05G-037
78:07B-017
Soil Radiation
78:020-001
78:020-006
Soil Sampling
78:05A-011
Soil Sampling Procedure
78:05A-011
Soil Science
78:02G-001
78:02G-011
78:02G-014
78:02G-027
78:02G-063
78:02G-081
78.-02K-023
Soil Strength
78:040-006
Soil Surface
78:02G-031
Soil Temperature
78:02G-031
78:02K-061
78:03F-025
78:05A-022
78:076-033
Soil Tests
78:021-005
78:02K-028
78:02K-045
78:02K-051
78:02K-069
78-.02K-075
78:03F-003
78:078-003
78:076-004
78:07B-010
78:078-012
78:078-017
78:078-019
78.-07B-024
78.-08G-002
Soil Texture
78:02G-042
78:02G-079
78:02J-027
78-.02K-050
78:03F-060
78:048-009
Soil Treatment
78:02F-002
338
-------
Soil Types
78:02G-028
78:02G-041
78:02G-055
78:02J-002
78:02K-018
78:058-005
78:078-001
Soil Water
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
78:
02C-001
02D-008
02G-001
02G-003
02G-006
02G-008
02G-009
02G-010
02G-011
02G-012
02G-016
02G-025
02G-027
02G-028
02G-041
02G-044
02G-052
02G-054
02G-055
02G-059
02G-066
02G-075
026-079
020-080
02G-084
020-085
;02G-086
;02K-028
;03F-021
:04A-005
:04B-008
;05B-018
:06A-001
:07B-017
;07B-022
:07B-036
Soil Water Movement
78:02A-010
78:020-001
78:02G-002
78:02G-003
78:02G-006
78:02G-007
78:02G-009
78:02G-010
78:02G-012
78:026-015
78:026-016
78:026-017
78:026-019
78:026-022
78:026-025
78:02G-027
78:026-028
78:02G-041
78:02G-045
78:026-046
78:026-047
78:026-049
78:026-050
78:02G-052
78:020-053
78:02G-054
78:020-055
78:020-059
78:02G-060
78:020-061
78:020-062
78:020-063
78:020-065
78:020-066
78:020-067
78:020-068
78:020-072
78:020-076
78:020-077
78:020-078
78:020-081
78:020-084
78:020-085
78:020-086
78:021-008
78:02K-024
78:03F-013
78:04A-005
78:05B-018
78:05B-039
78:056-034
78:06A-009
Soil-Water-Plant
Relationships
78:02A-007
78:02A-008
78:026-074
75:021-002
78:021-006
78:021-008
78:021-015
78:021-031
78:021-036
78:03C-003
78:03F-008
78:03F-021
78:03F-056
78:03F-109
78:048-008
Soil-Water Retention
78:026-079
Soils
78:02E-010
78:02F-019
78:02F-028
78:026-002
78:026-003
78:020-004
78:026-008
78:026-010
78:026-018
78:026-022
78:026-027
78:026-028
78:026-040
78:026-041
78:026-055
78:026-062
78:026-079
78:020-081
339
78:02J-001
78:02J-002
78:04A-002
78:04A-018
78:040-001
78:040-002
78:040-008
78:058-003
Solubility
78:021-017
78:02K-012
78:02K-013
Soluble Nutrients
78:050-037
Solute
Solutes
78:020-009
78:02G-006
78:020-008
78:020-012
78:020-013
78:020-015
78:020-019
78:020-020
78:020-040
78:020-046
78:020-065
78:020-077
78:020-078
78:021-013
78:02K-024
78:02K-062
78:058-013
78:05B-062
Solvent Extractions
78:07B-018
Sorghum
78:020-046
78:021-003
78:03F-051
78:03F-095
78:07B-012
Sorption
78:026-022
78:026-056
78:02K-015
78:040-001
78:05B-028
78:058-033
78:058-034
78:078-016
South Carolina
78:040-006
South Dakota
78:021-016
Southeast United States
78:03F-061
78:03F-078
-------
Soybeans
78:026-026
78:021-001
78:021-009
78:021-010
78:021-036
78:03F-001
78:03F-021
78:03F-051
78:048-005
78:056-001
78:05G-007
78:05G-029
78:05G-043
Spatial Distribution
78:02F-023
78:02J-014
78:03F-126
78:07A-003
Specific Yield
78:02F-027
78:026-042
Specifications
78:03F-043
78:08A-004
Spectrometers
78:02K-059
Spectrophotometry
78:078-012
78:078-018
Spectroscopy
78:02K-030
Spoil Banks
78:05G-001
Sprinkler Irrigation
78:02G-044
78:021-041
78:03F-007
78:03F-020
78:03F-030
78:03F-040
78:03F-041
78:03F-044
78:03F-045
78:03F-047
78:03F-058
78:03F-063
78:03F-064
78:03F-065
78:03F-069
78:03F-070
78:03F-071
78:03F-072
78:03F-074
78:03F-075
78:03F-076
78:03F-077
78:03F-078
78:03F-081
78:03F-084
78:03F-085
78:03F-091
78:03F-092
78:03F-097
78:03F-098
78:03F-102
78:03F-103
78:03F-104
78:03F-105
78:03F-114
78:03F-126
78:048-014
78:05A-002
78:058-011
78:058-022
78:05G-002
78:05G-010
78:06A-007
78:068-007
Stability
78:020-002
78:026-014
78:02J-011
Stabilization
78:02J-011
Stable Isotopes
78:026-051
78:02K-001
78:02K-006
State Governments
78:056-068
State Space Formulation
78:02A-006
Statistical Methods
78:020-007
78:02F-025
78:026-074
78:03F-030
78:03F-064
78:03F-065
78:03F-105
78.-04A-015
78:048-009
78:05A-008
78:05A-015
78:056-046
78:07A-003
Statistical Models
78:02A-001
78:028-001
78:02E-002
78:02F-007
78:026-018
78:026-042
78:05A-007
Statistics
78:020-001
78:02E-002
78:02F-011
78:05A-007
78:060-001
Steady Flow
78:02F-010
78:02F-017
78:02F-018
78:026-007
78:026-047
78:026-050
78:026-054
78:026-064
78:02G-077
78:02G-078
78:03F-110
78:058-017
78:058-059
78:06A-005
Stemflow
78:021-020
Stochastic Models
78:02J-013
Stochastic Processes
78:02A-007
78:02A-010
78:028-001
78:020-001
78:02E-002
78:02E-004
78:02E-005
78:02E-007
78:02E-008
78:02E-009
78:02F-007
78:02F-013
78:02F-023
78:02F-025
78:026-074
78:02J-013
78:04A-001
78:04A-004
78:04A-008
78:08E-001
Stomata
78:021-015
Storage Capacity
78:02F-020
78:04A-008
Storage Coefficient
78:02A-003
Storm Runoff
78:02.A-007
78:02A-009
78:040-005
78:058-006
78:058-014
78:06A-015
78:068-020
Storms
78:028-001
78:02E-002
78:04A-008
Stratification
78:026-075
340
-------
Stratified Flow
78:02G-007
Strawberries
78:03F-074
Stream Erosion
78:02J-011
78:02J-028
Stream Gages
78:073-032
Stream Response
78:05G-031
Streamflow
78:02A-011
78:02E-001
78:02E-003
78:02E-004
78:02E-005
78:02E-008
78:02J-008
78:058-065
78:06A-014
78:07A-002
Streams
78:020-001
78:02E-005
78:04A-001
78:05A-007
78:05B-042
78:058-049
78:05B-064
Strip Mine Wastes
78:05G-001
Structural Models
78:02K-030
Structures
78:050-028
Subcritical Flow
78:086-002
Submerged Plants
78:021-037
78:02K-043
78:03F-006
78:06A-006
Submerged Vegetation Stage
78:06A-006
Submergence
78:02G-035
78:02G-036
78:058-056
78:06A-006
Subsurface Drainage
78:02G-057
78:02G-058
78:02J-019
78:02K-052
78:03F-124
78:04A-015
78:048-005
78:048-006
78:048-007
78:048-009
78:05G-018
78:05G-023
78:050-026
78:06A-004
78:06A-005
78:08A-002
78:08G-002
78:08G-003
Subsurface Drains
78:02F-028
78:020-058
78:02K-052
78:048-005
78:048-006
78:048-009
78:06A-004
78:06A-005
78:06C-001
78:08A-002
78:08G-002
78:08G-003
Subsurface Flow
78:02F-007
78:02F-023
78:048-012
78:058-012
78:058-052
78:06A-009
Subsurface Irrigation
78:03F-063
78:058-011
Subsurface Runoff
78:04A-015
78:058-034
Sudangrass
78:021-007
Sugar Beets
78:021-030
78:03F-028
78:03F-125
Sulfur
78:021-017
78:02K-031
Sugarcane
Sulfates
78:030-002
78:03F-089
78:02K-013
78:02K-015
78:02K-028
78:02K-030
78:02K-073
Sulfides
78:02K-013
Sulfonates
78:050-001
Sulfur Compounds
78:03F-029
Supplemental Irrigation
78:021-001
78:021-026
78:03F-001
Surface Drainage
78:04A-015
78:048-007
78:050-018
78:050-023
Surface Irrigation
78:03F-034
78:03F-047
78:03F-054
78:03F-063
78:03F-081
78:03F-083
78:03F-084
78:03F-085
78:03F-086
78:03F-096
78:03F-100
78:03F-115
78:03F-116
78:03F-128
78:04A-007
78:04A-013
78:04D-008
Surface Runoff
78:02A-005
78:02A-008
78:020-005
78:02E-010
78:02E-011
78:020-058
78:02J-004
78:02J-010
78:02J-012
78:02J-018
78:04A-012
78:04A-013
78:04A-015
78:04A-017
78:058-007
78:058-008
78:058-023
78:058-024
78:058-034
78:058-037
78:058-044
78:050-030
78:088-007
78:100003
Surface Runoff Plots
78:05A-011
Surface Sealing
78:02J-027
341
-------
Surface Water Runoff
78:040-003
Surface Waters
78:05A-021
78.-05G-034
Surface-Groundwater
Relationships
78;02F-015
78:058-002
78:05G-031
78:05G-033
Thawing
78.-02G-020
Surveys
78-.05A-001
78.-05B-042
Suspended Load
78.-02J-003
78:02J-004
78:02J-013
78:020-018
Suspended Solids
78.-04D-001
78:086-013
Suspension
78:02J-018
78-.02K-012
78:02K~073
Sweet Corn
78:021-020
78:021-021
78:02K-023
78.-03P-D25
78:037-027
78:03F-031
78:03F-033
78:03F-056
78:03F-073
78:05A-004
78:05B-025
78:05G-021
78:076-012
Swimming Facilities
78:05A-015
Symbiosis
78.-020-026
78-.05G-007
78:976-006
Synthetic Hydrology
78:02A-005
78.-02E-001
78-.02E-002
78:02E-007
Synthetic Models
78.-02J-013
systemics
78:02K-025
Systems Analysis
78:03F-095
78:056-009
78:05G-003
78:05G-004
Tailwater
78:03F-035
78:03F-106
78.-03F-123
78:04A-013
Techniques
78:07B-002
Technology
78-.02A-001
Temperature
78:02F-021
78:02G-031
78:021-011
78:021-013
78:02J-002
78s02K-012
78:02K-038
78:053-015
Temperature Profile
78:02H-002
Tensiometers
78:02G-011
78:02G-025
78:02G-076
78:021-038
78:03F-001
78:03F-039
78:07A-001
Tension Lysimeter
78:02G-005
Terracing
Testing
78:02J-006
78:04A-009
78-.04A-010
78:068-012
78:02F-001
78:03F-058
78:03F-091
Testing Procedures
78:02J-002
78:03F-091
Texas
78:02D-004
78.-03F-047
78-.04A-010
78:048-006
78.-04D-005
7fi:05B-023
78:058-024
78:055-026
78:05C-001
78:068-015
7BJ06E-003
Texas Water Plan
78:020-004
342
Theoretical Analysis
78:02F-004
78:02F-009
78-.Q2G-Q04
78.-02G-006
78.-02G-036
78:026-042
78:02G-048
78:02G-063
78:02G-077
78:02G-080
78:05B-039
78:08B-013
Thermal Conductivity
78:02G-020
Thermal Pollution
78:058-015
78:05G-031
Thermal Powerplants
78:048-001
Thermal Radiation
76:020-006
Thermal Stratification
78:02H-002
Thermocline
78:02C-001
Thermoclynamic Behavior
78:02K-047
Thermodynamics
\ 78.-02K-035
Three-Dimensional
Simulation Analysis
78-.02F-015
Throughfall
78:05A-012
Tile Drainage
7S:02G-065
78t02J-019
78:02J-026
7B:03F-124
78:04A-005
78:05A-004
78:056-021
78.-05G-025
Tile Drains
78:02J-026
78.-04A-005
Tiles
Till
78:03F-130
78t02E-011
78:03F-108
-------
Time
Time Lag
78:020-082
78:02K-012
78:02K-038
78:03F-099
78:03F-100
Time Series Analysis
78:02E-004
78:02E-007
78:02E-008
78:02E-009
78:04A-008
Timing
Tobacco
Tomato
Tomatoes
Toxicity
78:021-030
78:02f(-005
78:02K-018
78:03F-049
78:03F-051
78:03F-115
78:03F-118
78:05G-070
78:068-009
78:021-002
78:021-017
78:02K-019
78:058-043
78:03F-007
78:030005
78:03F-074
78:058-040
78:021-010
78:021-024
78:02K-027
Trace Elements
78:021-010
78:021-032
78:02K-059
78:02K-064
78:05A-005
78:058-042
Tracers
78:020-066
78:021-030
78:058-052
Trafficability
78:048-007
Transient Flow System
78:058-060
Transition Flow
78:088-002
Translocation
78:021-014
78:021-018
78:03F-022
Transmissivity
78:02A-003
Transpiration
78:02A-011
78:021-015
78:021-019
78:021-031
Transpriation Dispersion
78:02G-062
Trap Efficiency
78:02J-028
78:08A-004
Travel Time
78:02G-045
78.-02G-065
78:02G-077
78:02G-078
78:058-021
78:058-062
Turgidity
Treatment
Trees
Trenches
78:03F-050
78:058-041
78:048-006
78:050-026
78:060001
78:08A-002
Tributaries
78:058-001
Trickling
Tritium
78:03F-087
78:02G-040
Tropic Level
78:050006
78:050007
Tubes
78:08G-002
78:08G-003
Turbulence
78:02J-014
78:058-015
78:058-061
Turbulent Energy Flux
78:020-002
Turf Grasses
78:03F-003
78:05A-002
78:053-011
Turnouts
78:021-015
78:021-031
78:03F-128
Unconsolidated Sediments
78:02J-003
Underground Storage
78:048-013
Uniform Flow
78:058-013
78:058-017
Uniformity
78:03F-030
78:03F-058
78:03F-064
78:03F-071
78:03F-072
78:03F-076
78:03F-081
78:03F-097
78:03F-102
78:03F-104
78:03F-105
78:03F-127
78:068-005
Unit Hydrographs
78.-02J-004
Unsaturated Flow
78:02F-006
78:02G-004
78:026-009
78:02G-012
78:02G-015
78:02G-017
78:02G-018
78:02G-024
78:02G-042
78:02G-043
78:02G-047
78:02G-048
78:02G-053
78:02G-054
78:020-061
78:02G-062
78:020-085
78:02G-086
78:02K-062
78:03F-093
78:048-011
78:048-012
78:C6A-009
Unsaturated Soil
78:02G-002
Unsteady Flow
78:02E-003
78:02F-009
78:020-007
78:02G-012
343
-------
Unsteady Flow
(cont.)
78:02G-061
78:02G-086
Unsteady Rain
78:02G-052
Urbanization
78:05B-055
Urea Pesticides
78.-05B-026
Ureas
Utah
78:021-007
78:021-009
78:02K-001
78-.03F-029
78:03P-057
78:058-049
78:078-003
78:058-010
78:056-038
Vadose Water
78:02P-027
Valves
78:020-011
78:03F-053
78:03F-117
78:088-003
Vapor Pressure
78;02D-006
Variance Reduction
78:02E-001
Variability
78:02G-028
78:03C-001
78:03F-087
78:03F-105
Varieties
78:021-010
78:030001
78:03F-022
78:03F-028
Vectors (Biological)
78.-06G-001
Vegetable Crops
78:03F-010
Vegetables
78:053-040
Vegetation
78:02A-009
78:020-005
78t02E~010
78:020-068
78:020-074
78:03D-001
78:058-012
Vegetation Effects
78:02D-004
78.-02J-022
78.-05A-009
Velocity
78:02J-016
Vibrations
78:02J-016
78:08B-007
Viscous Flow
78.-02H-001
Voids
78:078-019
Volatility
78:021-033
78:02K-033
78:02K-040
78.-02K-043
78:02K-055
78:03F-017
78:03F-029
78:03F-057
78.-05A-022
78:058-030
Volumetric Analysis
78:078-022
Washington
78:058-049
78:05G-066
78:06A-007
78:060002
78:06E-013
Waste Disposal
78:03P-016
78:053-020
78:058-027
78:058-050
78:058-052
78:05G-019
Waste Treatment
78:058-009
78:050-059
Waste Water
78:050-006
Waste Water Disposal
78:058-047
78:06E-004
Waste Water Pollution
78:058-047
78:100006
Waste Water Treatment
78:056-005
78:06E-004
78:100006
Wastes
78:05A-017
344
Water
78:05A-019
78:058-019
78:058-039
78:05G-071
78:06A-016
78:06A-001
Water Allocation
(Applied)
78:04A-003
Water Allocation
(Policy)
78:05G-033
Water Analysis
78:02K-023
78:03F-032
78:05A-008
78:05A-015
Water Balance
78:02A-007
78:02A-008
78:020-005
78:02G-038
78.-02G-068
78:02G-074
78:021-037
78:03F-056
78j03F-109
78.-03F-123
Water Chemistry
78:02K-023
78:02K-044
78.-05A-010
Water Conservation
78:02J-006
78:038-001
78:03D-001
78:03F-007
78:03P-026
78:03F-033
78:03F-034
78:03F-035
78:03F-039
78:03F-041
78:03F-043
78.-03F-044
78:03F-045
78:03F-046
78:0.3F-047
78:03F-048
78.-03P-049
78:03P-050
78:03P-051
78:03P-052
78:03F-053
78.-03F-055
78s03F-Q€4
78:03P-079
78:03F-080
78:03F-088
78s03F-093
78:03F-106
78i03F-107
-------
Water Conservation
(cont.)
78:03F-110
78:03F-118
78:03F-127
78:04A-010
78:05G-049
78:05G-065
78:05G-068
78:06E-011
Water Consumption
78:02F-005
Water Costs
78:03F-092
78:03F-107
78:05G-016
Water Delivery
78:03F-107
Water Demand
78:04A-008
78:05G-016
78:060-001
78:060-002
78:10C-005
Water Distribution
78:058-022
78:05G-011
Water Distribution
(Applied)
78:03F-034
78:03F-092
78:03F-103
78:03F-127
Water Harvesting
78:03F-123
Water Hyacinth
78:020-004
Water Injury
78:03F-096
Water Law
78:03F-107
78:043-004
78:05G-005
78:05G-012
78:05G-013
78:05G~014
78:05G-015
78:05G-024
78:05G-048
78:05G-059
78:050-073
78:06A-007
78:06B-011
78:06E-001
78:06E-003
78:06E-004
78:06E-007
78:06E-009
78:06E-010
78:06E-020
Water Levels
78:02F-012
78:078-025
Water Level Fluctuations
78:078-025
Water Level Recorders
78:078-025
Water Loss
78:020-004
78:04A-013
78:058-022
78:05G-009
Water Management (Applied)
78:02G-076
78:021-027
78:021-034
78:021-037
78:021-040
78:021-042
78:02K-065
78:03F-001
78:03F-008
78:03F-045
78:03F-046
78:03F-048
78:03F-052
78:03F-059
78:03F-060
78:03F-061
78:03F-062
78:03F-069
78:03F-071
78:03F-073
78:03F-080
78:03F-107
78:03F-112
78:04A-001
78:04A-004
78:04A-01L3
78:048-004
78:048-008
78:04C-001
78:058-020
78:05G-005
78:050-028
78:05G-035
78:050-039.
78:056-042
78:05G-044
78:05G-045
78:05G-047
78:05G-048
78:05G-055
78:05G-060
78:05G-068
78:05G-071
78:05G-077
78:06A-013
78:068-009
78:06E-011
78:06E-020
78:066-001
78:06G-003
78:10A-001
78:10C-005
78:10C-006
Water Management
78:03F-015
Water Policy
78:03F-079
78:04A-003
78:05G-055
Water Pollution
78:021-030
78:02J-003
78:02J-020
78:02J-022
78:02J-027
78:02K-048
78:02K-049
78:02K-053
78:02K-061
78:02K-064
78:03F-015
78:04A-016
78:040-008
78:05A-001
78:05A-004
78:05A-016
78:05A-017
78:05A-018
78:05A-019
78:05A-020
78:058-001
78:058-007
78:058-010
78:058-016
78:058-022
78:058-030
78:058-031
78:058-032
78:058-034
78:058-035
78:058-037
78:058-038
78:058-039
78:058-040
78:058-041
78:058-042
78:058-046
78:058-047
78:058-052
78:058-056
78:058-057
78:058-058
78:058-059
78:058-060
78:058-064
78:058-067
78:058-068
78:05C-006
78:050-009
78:05G-012
78:050-013
78:050-014
78:050-015
78:050-016
78:050-018
78:050-019
78:050-020
78:050-033
78:050-037
78:050-042
78:05G-043
345
-------
Water Pollution
(cont.)
78:05G-045
78:05G-046
78:05G-049
78:050-050
78:05G-055
78:050-059
78:050-060
78:05G-061
78:050-063
78:050-064
78:050-065
78:050-066
78:050-067
78:050-070
78:050-071
78:050-072
78:050-073
78:050-074
78:050-075
78:050-076
78:050-077
78:06A-001
78.-06A-016
78:068-010
78:068-014
78:066-015
78:06B-017
78:06B-019
78:06B-020
78:06E-001
78:06E-002
78.-06E-004
78.-06E-005
78:06E-009
78:06E-010
78:06E-011
78:06E-013
78:06E-014
78:06E-020
78:060-001
78:076-026
78.-10C-002
78.-10C-003
78:100-006
Water Pollution Control
78:03F-032
78:05A-019
78:058-009
78:058-030
78:058-065
78:050-003
78:050-004
78:056-019
78:050-021
78:05G-022
78:050-039
78:050-043
78:050-047
78:050-048
78:050-049
78:050-050
78:050-055
78:050-058
78:050-059
78:050-060
78:050-061
78:050-062
78:050-063
78;Q5G-064
78:050-066
78:050-068
78:050-069
78:050-071
78:050-073
78:05G-074
78:050-077
78:068-010
78:06B-014
78:06B-015
78:06E-004
78:06E-005
78:06E-006
78:06E-009
78:06E-010
78.-06E-013
78:06E-020
78:100-002
Water Pollution Effects
78:058-002
Water Pollution Sources
78:05A-017
78:05A-022
78:058-002
78:058-004
78:058-014
78:058-017
78:058-026
78:058-031
78:058-041
78:058-057
78:058-058
78:058-062
78:058-065
78:056-067
78:058-068
78:050-019
78:050-022
78:050-037
78:050-047
78:050-048
78:050-049
78:050-051
78:050-061
78:050-062
78:068-012
78:06E-004
78:06E-005
78:06E-013
78:078-026
Water Pressure
78:020-085
78:021-004
78:021-031
78:03F-058
78:03F-097
78:03F-127
78:048-014
78:088-004
78:088-006
Water Properties
78s05B-007
346
Water Quality
78:02A-004
78:020-039
78:020-077
78:021-002
78:02J-003
78:02J-006
78:02J-015
78:02J-024
78:03C-003
78:03C-006
78.-03F-014
78.-03F-032
78:048-004
78-.05A-001
78:05A-007
78:05A-008
78:05A-016
78:05A-017
78:05A-018
78:05A-020
78:05A-021
78:058-006
78:058-008
78:058-010
78:058-014
78:058-021
78:058-022
78:058-024
78:058-025
73:058-026
78:058-030
78:058-031
78:058-032
78:058-037
78:058-038
78:058-039
78:058-040
78:058-044
78:058-046
78:058-048
78:058-049
78:058-064
78:058-068
78:05C-007
78:050-005
78:050-008
78:050-009
78:050-010
78:050-012
78:050-013
78:050-014
78:050-015
78:050-016
78:050-018
78:050-019
78:050-024
78:050-025
78:050-029
78:050-030
78:050-031
78:050-033
78:050-035
78:050-037
78:050-039
78:050-042
78:050-044
78:050-046
78:050-047
78:050-048
78:050-049
-------
Water Quality
(cent.)
7B:05G-050
78:050-055
78:050-059
78:05G-060
78:05G-061
78:05G-062
78:05G-063
78:05G-064
78:05G-065
78:05G-066
78:05G-067
78:05G-069
7B:05G-070
78:05G-071
78:05G-073
78:05G-075
78:05G-076
78:05G-G77
78:C6A-001
78:06A-008
78:06A-014
78:06B-001
78:063-002
73:068-014
78:06B-01S
78:06B-017
78:06B-019
78:066-020
78.-06E-001
78.-06E-006
78:06E-009
78:06E-010
78:06E-0.13
78:06E-014
7S:06E-015
78:06E-020
78:07A-003
78:073-026
78:10A-001
78:10C-003
78:100-0.06
Water Quality Act
78.-05G-022
78:05G-048
78:05G-049
78:05G-050
78:056-062
78:05G-068
78:050-069
78:05G-071
78:06E-004
78:06E-005
7B:06E-006
78:06E-010
78:06E-014
78:100006
Water Quality Control
78:02A-004
78:048-006
78:05A-018
78J05A-019
78:053-002
78:»5G-C19
78:05G-020
78:05G-022
78:05G-024
78:05G-039
78:05G-043
78:05G-049
78:05G-050
78:05G-051
78:055-055
78.-05G-058
78:050-060
78:05G-061
78:05G-062
78-.05G-066
78:05G-067
78:050-068
78:050-069
78:05G-070
78:05G-071
78-.05G-075
78:050-076
78:06B-010
7B:06B-014
78.-06S-015
78:063-019
7S:06E-004
78:06E-009
78:06E-010
78:06E-011
78:06E-013
•78J06E-014
78:06E-020
78:100-006
Water Quality Standards
78.-05A-015
Water Requirements
78:02G-076
78:021-003
78:021-034
78:021-036
78:021-037
78:021-038
78:021-040
78:021-041
78:021-042
7B:03D-001
78.-03F-031
78:048-001
78.-06D-002
Water Resources
78:02A-002
7B:02F-018
78:046-001
78:05B-017
78:06A-001
78:06A-010
Water Resources Development
78:06A-010
78.-06C-002
Water Resources Planning
Act
78:06E-004
Water Reuse
78:046-014
Water Rights
7B:04B-004
78:05G-012
78:05G-013
78:05G-014
78:050-015
78:06E-001
78.-06E-003
78.-06E-007
Water Sampling
78.-05B-002
78:07B-026
Watershed Management
78:02A-011
78:02J-022
78:05G-002
78:05G-065
78:06A-015
Watersheds (Basins)
78:02A-005
78:02F-011
78:02J-005
78:040-001
78:04D-005
78-rt)5B-023
Water Shortage
18:03P-035
7&:03P-041
78:03P-053
78:03P-058
78:03P-077
78:03F-080
7Bs03P-088
Water storage
78:048-004
78:048-013
78:06E-007
78:078-022
Water Supply
78:043-001
7S:06E-007
78:083-010
Water Table
78:02P-020
78:02G-003
78:02G-038
78:02G-057
78:020-081
78?03F-125
78:04B-002
78:04B-008
78:04B-009
78:058-035
78:05G-002
78:05G-025
78:06A-004
78:06A-005
Water Table Aquifers
73.-02F-017
78:02F-027
78:02F-028
347
-------
Water Temperature
78:020-001
78:02E-005
78:050-031
Water Transfer
78:05G-033
Water Treatment
78:03F-032
78.-05G-038
Water Tunnels
78:088-007
Water Utilization
78:03D-001
78.-03F-009
78:06E-003
Water Wells
78:02F-016
78:05A-010
78.-05B-039
78:05B-062
Water Yield
78:02A-007
78:02J-019
78:04A-006
78:04A-012
78:06A-015
78:076-026
Wave Velocity
78:02A-002
Waves (Water)
78:086-001
78:08B-012
Weather Data
78:02A-001
78:021-035
Weathering
78:02K-007
Weed Control
78:02K-016
78:03F-108
78:056-006
78:056-023
78:056-029
Weeds
78:02K-016
Well Casings
78:058-062
Well Contamination
78:058-039
Well Data
Wells
78:03F-017
78:02F-016
78:04A-001
78:048-010
78:056-016
78:058-039
78:068-009
Yolo Loam
Wetting
78:02G-001
78:02G-022
78:020-030
78:02G-067
78:02G-080
78:02G-084
78:056-001
Wetting Front
78.-02G-034
Wheat
Wiers
78:020-046
78:020-076
78:021-008
78:021-026
78:030-001
78:03F-002
78:03F-022
78:03F-024
78:04A-012
78:05B-044
78:050-021
78:076-005
78:078-007
78:086-009
Wind Erosion
78:02J-021
78:040-007
Wind Velocity
78:03F-076
Wisconsin
78:02G-028
Withdrawal
X-Ray
Xylem
78:02H-001
78:02K-013
78:02K-073
78:021-004
78:021-015
Zinc
78:02J-002
78:021-032
78:02K-010
78:02K-013
78.-02K-027
78:02K-072
78:03F-006
78:03F-025
78:058-055
Yakima Valley (Washington)
78:0"5G-033
Yield Equation
78:021-003
78:021-036
78:021-040
78:021-041
78:021-042
78:03F-031
78:03F-048
78:03F-062
78:03F-092
78:066-021
348
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-80-073
3. RECIPIENT'S ACCESSIONING.
4. TITLE AND SUBTITLE
SELECTED IRRIGATION RETURN FLOW QUALITY
ABSTRACTS 1978, Eighth Annual Issue
5. REPO'RT DATE
April 1980 issuing date
6. PERFORMING ORGANIZATION CODE
'7. AUTHOR
------- |