EPA-600/2-76-019
March 1976
Environmental Protection Technology Series
SELECTED IRRIGATION RETURN FLOW
QUALITY ABSTRACTS, 1974
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Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into five series. These five broad
categories were established to facilitate further development and application of
environmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed to develop and
demonstrate instrumentation, equipment, and methodology to repair or prevent
environmental 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.
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EPA-600/2-76-019
March 1976
SELECTED IRRIGATION RETURN PLOW
QUALITY ABSTRACTS, 1974
Fourth Annual Issue
by
Gaylord V. Skogerboe
Wynn R. Walker
Stephen W. Smith
Colorado State University
Fort Collins, Colorado 80521
Grant No. R-800426
Project Officer
James P. Law, Jr.
Robert S. Kerr Environmental Research Laboratory
U.S. Environmental Protection Agency
Ada, Oklahoma 74820
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
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DISCLAIMER
This report has been reviewed by the Office of Research and
Development, 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. Environ-
mental Protection Agency, nor does mention of trade names or
commercial products constitute endorsement or recommendation
for use.
ii
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FOREWORD
The fourth annual issue of SELECTED IRRIGATION RETURN PLOW QUALITY
ABSTRACTS has been compiled from approximately 100 sources of ma-
terial covering calendar year 1974. This compilation 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 pertinent to Irri-
gation Return Flow Quality through 1967. The first annual issue of
SELECTED IRRIGATION RETURN FLOW QUALITY ABSTRACTS listed publica-
tions appearing in calendar years 1968 and 1969, while the second
annual issue listed publications appearing in calendar years 1970
and 1971, and the third annual issue contained abstracts of articles
and reports published during calendar years 1972 and 1973. The
fourth annual issue contains 422 abstracts of documents published
during calendar year 1974. 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 pub-
lication, "Selected Water Resources Abstracts."
13.1
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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 insti-
tutions 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 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 irri-
gation 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, and the third annual issue covers calendar years 1972 and
1973. This annual issue lists publications printed in 1974.
This report was submitted in fulfillment of Grant Number R-800426
under the sponsorship of the Office of Research and Development,
Environmental Protection Agency.
Key Words: Fertilizers, Irrigated Land, Irrigation Systems, Irri-
gation Water, Nitrates, Phosphates, Return Flow, Salinity, Water
Pollution Effects, Water Pollution Sources, Water Quality Control.
IV
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TABLE OF CONTENTS
Section
I WATER CYCLE - General (Group 02A) 1
II WATER CYCLE - Snow, Ice, And Frost (Group 02C) 3
III WATER CYCLE - Evaporation And Transpiration (Group 02D) 4
IV WATER CYCLE - Streamflow And Runoff (Group 02E) 6
V WATER CYCLE - Groundwater (Group 02F) 8
VI WATER CYCLE - Water In Soils (Group 02G) 17
VII WATER CYCLE - Water In Plants (Group 021) 35
VIII WATER CYCLE - Erosion And Sedimentation (Group 02J) 36
IX WATER CYCLE - Chemical Processes (Group 02K) 40
X WATER SUPPLY AUGMENTATION AND CONSERVATION - Water Yield 41
Improvement (Group 03B)
XI WATER SUPPLY AUGMENTATION AND CONSERVATION - Use Of Water Of 42
Impaired Quality (Group 03C)
XII WATER SUPPLY AUGMENTATION AND CONSERVATION - Conservation In 44
Agriculture (Group 03F)
XIII WATER QUANTITY MANAGEMENT AND CONTROL - Control Of Water On The 108
Surface (Group 04A)
XIV WATER QUANTITY MANAGEMENT AND CONTROL - Groundwater Management 113
(Group 04B)
XV WATER QUANTITY MANAGEMENT AND CONTROL - Watershed Protection 120
(Group 04D)
XVI WATER QUALITY MANAGEMENT AND PROTECTION - Identification Of 122
Pollutants (Group 05A)
XVII WATER QUALITY MANAGEMENT AND PROTECTION - Sources Of Pollution 124
(Group 05B)
XVIII WATER QUALITY MANAGEMENT AND PROTECTION - Effects Of Pollution 147
(Group 05C)
XIX WATER QUALITY MANAGEMENT AND PROTECTION - Water Treatment 150
Processes (Group 05D)
XX WATER QUALITY MANAGEMENT AND PROTECTION - Water Quality 152
Control (Group 05G)
XXI WATER RESOURCES PLANNING - Techniques Of Planning (Group 06A) 154
XXII WATER RESOURCES PLANNING - Evaluation Process
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TABLE OF CONTENTS (Cont'd)
Section
XXVI WATER RESOURCES PLANNING - Ecologic Impact Of Water
Development (Group 06G)
XXVII WATER RESOURCES - Data Acquistion (Group 07B)
XXVIII RESOURCES DATA - Evaluation, Processing And Publication
(Group 07C)
XXIX ENGINEERING WORKS - Structures (Group 08A)
XXX ENGINEERING WORKS - Hydraulics (Group 08B)
XXXI ENGINEERING WORKS - Hydraulic Machinery (Group 08C)
XXXII ENGINEERING WORKS - Soil Mechanics (Group 08D)
XXXIII AUTHOR INDEX
XXXIV SUBJECT INDEX
Page
164
165
169
171
175
177
179
181
193
VI
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ACKNOWLEDGEMENTS
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 efforts of Ms. Betty Doss, Ms. Lee Kettering,
Ms. Teresa Skogg, and Ms. Sandra Geohring in preparing the
necessary forms which are forwarded to the Water Resources
Scientific Information Center are sincerely appreciated,
as well as the typing of this final report. The organi-
zational procedures, which have proven highly effective,
are the result of previous efforts by Ms. Betsy Zakely.
The scope of this literature abstracting effort has
been delineated jointly by the senior author and the
Project Officer, Dr. James P. Law, Jr., Program Director,
Agricultural Wastes Section, Treatment and Control
Research, 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.
vn
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Section I
WATER CYCLE
GENERAL (GROUP 02A)
74:02A-001
CALIBRATING A WATER YIELD MODEL FOR SMALL UNGAGED WATERSHEDS,
Jarboe, J.E. and Haan, C.T.
Kentucky Department of Natural Resources, Frankfort, Division of Water.
Water Resources Research, Vol. 10, No. 2, p 256-262, April 1974. 1 fig,
10 tab, 8 ref.
Descriptors: *Water yield, *Mathematical models, *Kentucky, Systems analysis,
Rainfall-runoff relationships, Optimization, *Small watersheds.
A four-parameter water yield model was calibrated on 17 Kentucky watersheds
by relating the model parameters to watershed topographic, geologic, and soil
characteristics. The relationships were tested by comparing observed and
simulated runoff records from six watersheds that were not contained in the
original 17 watersheds. The results show that the water yield model can be
satisfactorily applied to ungaged basins.
74:02A-002
STREAMFLOW SIMULATION: 3. THE BROKEN LINE PROCESS AND OPERATIONAL HYDROLOGY,
Mejia, J.M., Dawdy, D.R. and Nordin, C.F.
Ecole Polytechnique, Montreal (Quebec). Hydraulic Division.
Water Resources Research, Vol. 10, No. 2, p 242-245, April 1974. 11 ref.
Descriptors: *Synthetic hydrology, *Simulation analysis, *Statistical models,
Markov processes. Stochastic processes, Regression analysis, Probability,
Variability.
Broken line processes can be used to produce a standardized Gaussian process.
An extension of the theory of the broken line process leading to the generation
of processes preserving the mean, the variance, and a skewness coefficient
different from zero is presented. The broken line process allows the modeling
of cross-correlated sequences, for which it is possible to reproduce the value
of H, the second spectral moment fox a continuous process or the first serial
correlation coefficient for a discrete one, and the first three moments for
each of the sequences as well as the lag zero cross correlation among them.
In addition, by proper structuring of the broken line process, parameter
estimates may be preserved by simple algorithms. The addition of simple
broken line processes is a useful operational tool for the synthesis of skewed
multivariate sequences exhibiting the Hurst phenomenon. It can be used for
continuous as well as discrete processes.
74:02A-003
MODELING OF STOCHASTIC-DETERMINISTIC HYDROLOGIC SYSTEMS,
Laurenson, E.M.
Monash University, Clayton, Australia, Department of Civil Engineering.
Water Resources Research, Vol. 10, No.'5, p 955-961, October 1974. 5 fig, 6 tab,
3 ref.
Descriptors: *Hydrologic systems, ^Stochastic processes, *Hydrologic models,
*Flood frequency, *Jnit hydrographs, Storage, Tides, Analytical techniques, Stream-
flow, Flood peak, Model studies.
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Most hydrologic systems have both stochastic and deterministic components.
The stochastic components are parameters defined by means of probability dis-
tributions, whereas the deterministic components are processes that can be
modeled mathematically or graphically without probabilistic statements. Com-
bined modeling of the stochastic and deterministic aspects of systems can lead
to advances in many areas of hydrologic practice. Such modeling is achieved by
matrix multiplication of a probability distribution of the stochastic system
input with a transitional matrix derived from the deterministic operation of
the system and any stochastic parameter. This method was demonstrated for a
wide range of applications. The method does not help to define the deterministic
relations among variables nor the probability distributions of variables. It
does provide a convenient means of mixing the deterministic and the stochastic
aspects of systems.
74:02A-004
CHANGES IN ARTIFICIAL DRAINAGE, FERTILIZERS, AND CLIMATE IN SCOTLAND,
Green, F.H.W.
Oxford University, Parks Road, Department of Agricultural Science.
Journal of Environmental Management, Vol. 2, No. 2, p 107-121, April 1974.
10 fig, 2 tab, 6 ref.
Descriptors: *Environmental effects, Drainage effects, Drainage systems,
Fertilization, Fertilizers, Climatic data, Climates.
A recently published paper (Green, 1973) drew attention to certain environmental
changes, some natural and some man-made, which have been taking place concurrent-
ly in recent years, and which are affecting both water in streams, and the water
level in the soil. Because the available data, on either side of the Border,
were not strictly comparable, the former paper had to be restricted to England
and Wales. The present paper deals with Scotland in a generally similar manner.
The environmental changes considered are field drainage, use of fertilizers, and
climatic changes.
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Section II
WATER CYCLE
SNOW, ICE, AND FROST (Group 02C)
74:02C-001
EFFECTS OF SALT CONCENTRATION CHANGES DURING FREEZING ON THE UNFROZEN WATER
CONTENT OF POROUS MATERIALS,
Banin, A. and Anderson, D.M.
Cold Regions Research and Engineering Laboratory, Hanover, New Hampshire.
Water Resources Research, Vol. 10, No. 1, p 124-128, February 1974. 4 fig,
2 tab, 12 ref.
Descriptors: *Freezing, *Saline water, *Porous media, *Frozen soils. Frozen
ground, Permafrost, Frost, Soil water, Aqueous solutions, Equations, Salts.
By combining equations for salt concentration by water removal from porous
bodies with those for freezing point depression in normal solutions, equations
were developed for calculating freezing point depression shifts due to the
gradual removal of water upon freezing in porous bodies. The same equations
can be used for the calculation of shifts in the osmotic potential of the water
in drying porous bodies by using a simple conversion factor. Graphs relate
the remaining water content to the freezing point shift for various initial
soluble salt contents. Good agreement was found between the measured freezing
point depression in a silty clay soil treated with three concentrations of
sodium chloride and with dimethyl sulfoxide at various contents of unfrozen
water and the calculated values.
74:02C-002
WATER FLOW THROUGH SNOW OVERLYING AN IMPERMEABLE BOUNDARY,
Colbeck, S.C.
Cold Regions Research and Engineering Laboratory, Hanover, New Hampshire.
Water Resources Research, Vol. 10, No. 1, p 119-123, February 1974. 3 fig,
14 ref.
Descriptors: *Snowpacks, *Melt water, *Percolation, *Unsaturated flow, In-
filtration, Water yield, Temperature, Snowmelt, Glaciohydrology, Melting,
Mathematical models.
A two-layer model describes water flow over an impermeable boundary. The model
consists of vertical flow through an unsaturated layer and flow along a boundary
in a saturated layer. The governing equations are solved for the nonsteady
case, where the gradient of the thickness of the saturated layer is small com-
pared with the slope of the impermeable boundary. In most cases the discharge
from shallow snowpacks will preserve the diurnal cycles of input at the sur-
face, although for deep snowpacks (such as temperate glacier firn) the diurnal
cycle is smoothed and only long-term responses are expected. The flow of a
diurnal meltwater wave through a small (2.10 m deep by 100 m long) snowpack
was calculated as an example. The case of steady flow is also described.
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Section III
WATER CYCLE
EVAPORATION AND TRANSPIRATION (Group 02D)
74:020-001
A SENSITIVITY AND ERROR ANALYSIS OF PROCEDURES USED FOR ESTIMATING EVAPORATION,
McCuen, R.H.
Maryland University, College Park, Department of Civil Engineering.
Water Resources Bulletin, Vol. 10, No. 3, p 486-497, June 1974. 3 tab, 11 ref.
Descriptors: *Evaporation, Mathematical studies, Equations, Meteorology, Vari-
ability, Heat transfer, Heat budget, Winds, Model studies.
The structure of commonly used evaporation models, the effect of variation in
meteorological factors on observed evaporation rates, and the effect of error
in measurements of the meteorological factors were studied by sensitivity and
error analyses. Error in evaporation estimates resulting from measurement
error in meteorological factors in probably much less than 5% of the computed
evaporation rate. The importance of the different meteorological factors
varies in time and space. The sensitivity analysis indicates that the Frac-
tional-Evaporation Equivalent method is structurally inadequate and the Weather
Bureau model is more flexible than the Penman model. However, the Penman
model provides more realistic estimates of the importance of the various
meteorological factors.
74:020-002
PREDICTION OF WATER LOSS FROM A FALLOW FIELD SOIL BASED ON SOIL WATER FLOW
THEORY,
Gardner, H.R.
Agricultural Research Service, Fort Collins, Colorado.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 379-382, May-
June 1974. 6 fig, 1 tab, 4 ref.
Descriptors: *Evaporation, *Water loss, *Soil water movement, Equations,
Evapotranspiration, Diffusivity, Soil moisture, Water balance.
Evaporation from nonhomogeneous field soils may be predicted by a simple
technique based on soil water flow theory. From cumulative evaporation measure-
ments on undisturbed cores of soil, a dimensionless curve is drawn relating
fractional water loss to the square root of time divided by the amount of water
available for evaporation. A procedure is described to account for the resid-
ual water left in the soil from one rainfall event to the next. Predictions
of cumulative evaporation made by the use of the dimensionless curve were com-
pared with 4 years of lysimeter data on Rago silt loam. The system should
work best in an area with high average potential evaporation and low rainfall
such as the Great Plains.
74:020-003
ESTIMATING EVAPOTRANSPIRATION USING CANOPY TEMPERATURES: FIELD EVALUATION,
Stone, L.R. and Horton, M.L.
Kansas Agricultural Experiment Station, Manhattan^ Evapotranspiration Laboratory.
Agronomy Journal, Vol. 66, No. 3, p 450-454, 1974, Illus.
Thermal scanners provide a possible way of estimating water loss from surface
by using remotely sensed surface temperatures. In this study, designed to
evaluate the feasibility of using canopy temperatures in estimating evapo-
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transpiration(ET), 5 equations were used. Sorghum bicolor L. (Moench) was used
in the field investigation. Three of the equations were the well-known methods
of van Bavel, Penman and energy budget-Bowen ratio. The other 2 use the tem-
perature of the evaporating surface in estimating ET and are referred to as
the Bartholic-Namken-Wiegand (B-N-W) and Brown-Rosenberg (B-R) methods. Using
simple linear regression and correlation analyses, the B-N-W estimates were
found to be approximately 17% smaller and the B-R estimates to be approximately
22% larger than typical estimates obtained by the Penman and energy budget-
Bowen ratio methods. Both methods appear usable in determining ET rates of
vegetated surfaces, with the B-N-W method requiring less input data than the
B-R method.
74:020-004
WATER CONSUMPTION OF IRRIGATED CROPS,
Balogh, J.
Research Institute of Water Resources Management, Budapest, Hungary.
International Commission on Irrigation and Drainage, p 18-24, July 1974. 2 fig,
16 ref.
Descriptors: *Evapotranspiration, *Lysimeters, Irrigation, Moisture tension,
Consumptive use, Soil-plant-water relationships, Instrumentation, Irrigation
practices.
The author, in analyzing the variation in irrigation water requirement and irri-
gation water need, interprets the potential, maximal and actual values of evapo-
transpiration. For this purpose, he analyses the complex ensembles of the
vapour absorption and vapourizing systems of the soil-plant-atmosphere and vege-
tation space. He then examines the most important methods and instruments for
the evapotranspiration and the types of the obtainable values of evapotranspira-
tion. It has been established that the values of water consumption of irrigated
crops only diverge little from the values of its evapotranspiration, and the
evapotranspiration of irrigated crops is necessarily less than the potential or
maximal values of evapotranspiration, but it is always higher than the actual
evapotranspiration without irrigation.
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Section IV
WATER CYCLE
STREAMPLOW AND RUNOFF (Group 02E)
74:02E-001
SURFACE WATER NETWORK DESIGN BY REGRESSION ANALYSIS SIMULATION,
Moss, M.E. and Karlinger, M.R.
Geological Survey, Reston, Virginia, Water Resources Division.
Water Resources Research, Vol. 10, No. 3, p 427-433, June 1974. 7 fig, 1 tab,
5 ref.
Descriptors: *Streamflow forecasting, *Regression analysis, *Simulation anal-
ysis, Network design, *Water transfer, Water supply, Statistical models. Inter-
basin transfers, Water resources development, Planning, Water management(Ap-
plied) .
Statistical characteristics of the accuracy of regression analyses as used
in surface water regionalization were investigated by simulating logarithmic
regressions of the streamflow parameters, mean and standard deviation, de-
rived from synthetic streamflow sequences. Accuracy was measured in terms
of equivalent years of at-site record. A procedure for design of surface
water data networks that accounts for the statistical nature of estimates
of parameter accuracy is presented.
74 :02E-002
TWO-DISTRIBUTION METHOD FOR MODELING AND SEQUENTIAL GENERATION OF MONTHLY
STREAMFLOWS,
Singh, K.P. and Lonnquist, C.G.
Illinois State Water Survey, Urbana, Hydrology Section.
Water Resources Research, Vol. 10, No. 4, p 763-773, August 1974. 6 fig, 2 tab,
21 ref.
Descriptors: *Synthetic hydrology, *Time series analysis, *Model studies,
*Distribution patterns. Statistical methods, Streamflow, Hydrologic data,
Analytical techniques, Correlation analysis. Probability, Computer programs,
*Illinois.
Distributions of observed monthly streamflows at many gaging stations exhibit
slight, moderate, or sharp reverse curvatures that cannot be accommodated by
the commonly used classical distributions such as the normal and gamma (Pear-
son type 3) distributions applied to flows or their logarithms. The two
distribution, essentially a bimodal distribution, fits most of these observed
distributions very well. A unique and versatile method for modeling and se-
quential generation of monthly streamflows was presented. In order to assure
the normality of the multivariate distribution of variables representing
monthly flows, the flows or their logarithms were converted to standardized
normal deviates by suitable transforms. The distributions of monthly stream-
flows generated by the two-distribution method fit best the observed flow
distributions. Annual flows obtained by summing generated monthly flows fit
the observed annual flows very well. The use of the two-distribution method
can obviate arbitrary adjustments in generated monthly flows to bring the
annual flows obtained from them in line with observed annual flows.
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74:02E-003
HYDROCHEMISTRY OF THE ATHABASCA AND NORTH SASKATCHEWAN RIVERS IN THE ROCKY MOUN-
TAINS OF CANADA,
Drake, J.J. and Ford, D.C.
McGill University, Montreal, Quebec, Canada, Department of Geography.
Water Resources Research, Vol. 10, No. 6, p 1192-1198, December 1974. 4 fig,
3 tab, 12 ref.
Descriptors: *River flow, River forecasting, River systems, Model studies,
Rivers, Canada, Theoretical analysis.
The hydrochemical behavior of the Athbasca and North Saskatchewan rivers at
their points of departure from the Rocky Mountains during the period May 1967
to February 1970 is shown to be well represented by a model based upon the
mixing of two water bodies. These component sources contribute varying propor-
tions of the total discharge through the year. One of them has properties that
are in keeping with the theoretically expected and the observed characteristics
of surface runoff water in the area and essentially represents snowmelt water.
The properties of the other component are similarly in keeping with those
expected and observed for groundwater in the rock and glacial aquifers of the
area.
74:02E-004
PROCEDURES FOR DETERMINING THE ORDER OF DEPENDENCE IN STREAMFLOW RECORDS,
Denny, J.L., Kisiel, C.C. and Yakowitz, S.J.
Arizona University, Tucson, Department of Mathematics.
Water Resources Research, Vol. 10, No. 5, p 947-954, October, 1974. 2 tab, 17
ref.
Descriptors: *Streamflow, Streamflow forecasting, Streams, Markov processes,
Hydrology, Model studies, Statistical methods, Statistics.
As will be documented in detail, a common feature of all the Streamflow models
in the literature is that they assume some known order of Markov dependency to
be available prior to calibration of the model parameters. Yet the statistical
methods for finding this order are subtle and perhaps may themselves need refine-
ment. In brief, the problem of finding the minimum order of Markov dependence is
a difficult one and yet one that must be faced no matter what Streamflow model
is selected. This study is devoted in the main to setting forth the extant
statistical techniques available for this problem of determining Markov order
and applying the stated techniques to finding the order of records of particular
rivers in the Tucson basin. Care is taken in describing the hydrologic proper-
ties of the rivers studied, since these properties may ultimately be crucial in
establishing some a priori feelings for the range of likely orders.
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Section V
WATER CYCLE
GROUNDWATER (Group 02F)
74:02F-001
WATER-TABLE FLUCTUATION IN RESPONSE TO RECHARGE,
Marino, M.A.
California University, Davis, Department of Water Science and Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR2, Paper 10582, p 117-125, June 1974. 2 fig, 10
ref, append.
Descriptors: *Recharge, *Water level fluctuations, *Water spreading. Ground-
water, Equations, Irrigation, Water table, Surface-groundwater relationships.
Analytical expressions were developed to describe the rise and fall of the
water table in an extensive unconfined aquifer receiving localized vertical
recharge and discharging into a surface reservoir in which the water level
remains equal to that of the main flow before recharge. The rate of recharge
is maintained by a spreading area in the form of an infinitely long strip of
finite width. The solutions are expressed in terms of the head averaged over
the depth of saturation. They are applicable when the rise of the water table
is smaller than 50% of the initial depth of saturation. A numerical example
is presented.
74:02F-002
A DATA ACQUISITION SYSTEM FOR TRANSIENT POROUS MEDIA EXPERIMENTS IN A SECTOR
TANK,
Orhun, A. and Luthin, J.N.
California University, Davis, Department of Water Science and Engineering.
Water Resources Research, Vol. 10, No. 3, p 601-604, June 1974. 6 fig, 1 ref.
Descriptors: *unsteady flow, *Groundwater movement, Data collections, Perme-
ameters. Porous media, Hydraulic models, Piezometers, Data processing.
A simple •, fast, and reliable data acquisition system was designed to study
groundwater flow problems under transient conditions. The data needed in-
clude soil water pressure at various locations and the outflow from the well.
A sector tank was constructed for the experimental verification of the com-
puter solutions. The grid of pressure tap points was chosen in such a way that
interpolations for the equipotentials deviating from vertical lines could
easily be made along the diagonals of the network. All the pressure measure-
ments were made by piezometers constructed from 1/4-inch stainless steel
tubings.
74:02F-003
STOCHASTIC ANALYSIS OF PHREATIC AQUIFERS,
Gelhar, L.W.
Massachusetts Institute of Technology, Cambridge, Department of Civil Engineer-
ing.
Water Resources Research, Vol. 10, No. 3, p 539-545, June 1974. 6 fig, 19 ref.
Descriptors: *Surface-groundwater relationships, *Statistical models, *Sto-
chastic processes, Alluvial channels, Recharge, Discharge(Water), Water table,
Water level fluctuations.
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Three analytical models were developed to describe the spectral response char-
acteristics of phreatic aquifers subject to time variable accretion and fluc-
tuations in adjacent stream stage. A linear reservoir model approximates the
behavior of a more complete distributed linear model based on the Dupuit ap-
proximation if a single parameter is adjusted appropriately. A linearized
two-dimensional analysis including the effects of vertical flow shows, under
conditions of large anisotrophy with relatively narrow partially penetrating
streams, differences from the Dupuit analysis that may be important under some
field conditions. Possible applications of the results in aquifer evaluation
are suggested.
74:02P-004
SENSITIVITY ANALYSIS OF INPUT PARAMETERS IN NUMERICAL MODELING OF STEADY STATE
REGIONAL GROUNDWATER FLOW,
Gillham, R.W. and Farvolden, R.N.
Geulph University, Ontario, Department of Land Resource Science.
Water Resources Research, Vol. 10, No. 3, p 529-538., June 1974. 9 fig, 15 ref.
Descriptors: ^Numerical analysis, *Groundwater movement, *Groundwater basins,
Mathematical models, Finite element analysis, Hydraulic conductivity.
To study regional groundwater flow, a finite element model was used to examine
the sensitivity of computed hydraulic head values to changes in the hydraulic
conductivity, steady state saturated flow in non-uniform anisotropic cross
sections was considered. The sensitivity analysis procedure was useful in
locating those areas of the flow system most sensitive to changes in conduc-
tivity and in determining those components of conductivity that have the greatest
effect on the hydraulic head distribution. Consequently, a sensitivity analysis
is very useful in designing efficient hydraulic conductivity measurement pro-
grams. One method that has frequently been used to determine conductivities
is to adjust the conductivity components in a numerical model until the com-
puted head value agree with field measurements; this procedure could lead to
erroneous conclusions. By using sensitivity analyses, a method was developed
for determining the quantitative value of ratios of conductivity components
from field measurements of hydraulic head. In principle, the number of head
measurements must be equal to the number of unknown conductivity ratios.
74:02F-005
NONLINEAR TECHNOLOGICAL FUNCTIONS FOR AQUIFERS WHOSE TRANSMISSIVITIES VARY
WITH DRAWDOWN,
Maddock, T., III.
Geological Survey, Reston, Virginia.
Water Resources Research, Vol. 10, No. 4, p 877-881, August 1974. 1 fig, 7 ref.
Descriptors: *Drawdown, *Transmissivity, *Aquifers, *Water level fluctuations,
^Unsteady flow, Aquifer testing, Water table, Mathematical studies, Equations.
An algebraic technological function (AFT) exists for an aquifer whose flow to
wells can be remodeled by Boussinesq's equation. Drawdown is an infinite power
series in pumping values, and the ATF is provided by a finite sum of the power
series. The number of terms necessary for the finite sum to provide a good
approximation to the infinite series depends on a ratio of drawdown to saturated
thickness. The ATF can be used in optimization techniques or as a method for
predicting drawdowns from pumping.
74:02F-006
TRACING SHALLOW GROUNDWATER SYSTEMS BY SOIL TEMPERATURES,
-------
Cartright, K.
Illinois State Geological Survey, Urbana.
Water Resources Research, Vol. 10, No. 4, p 847-855, August 1974. 9 fig, 23
ref.
Descriptors: *Illinois, *Groundwater movement, *Soil temperature, *Heat flow,
Discharge(Water), Recharge, Aquifer characteristics, Glacial aquifers, Flow
system.
circulating water is known to affect the temperature of the rock through which
it flows. Analysis of existing theoretical equations suggests that shallow
groundwater flow will also affect the surface soil temperature. Soil temper-
atures therefore might be used to delineate small, shallow groundwater flow
systems; both recharge and discharge zones might be distinguished. Temperature
data taken in the field during summer and winter support these theoretical
conclusions and agree with the groundwater flow patterns inferred from hydro-
logic data. In general, winter soil temperature profiles have less data scatter
than profiles of summer temperatures. The greater the rate of groundwater flow,
the greater the temperature difference between recharge and discharge zones.
Temperature variations ranged from 0.75C in clayey glacial till to 5C in sand.
The effect on soil temperature also decreases with increasing horizontal dis-
tance between the recharge and the discharge zone. The effect of horizontal
flow in a shallow confined aquifer is also predictable from theoretical models
and can be shown by field studies. The amount of heat redistributed depends
on the thermal properties of the aquifer and on overburden and the velocity of
fluid flow.
74:02F-007
IDENTIFICATION OF PARAMETERS IN AN INHOMOGENEOUS AQUIFER BY USE OF THE MAXIMUM
PRINCIPLE OF OPTIMAL CONTROL AND QUASI-LINEARIZATION,
Lin, A.C. and Yeh, W. W-G.
California University, Los Angeles, Department of Systems Engineering.
Water Resources Research, Vol. 10, No. 4, p 829-838, August 1974. 3 fig, 3
tab, 13 ref, 1 append.
Descriptors: *Aquifer characteristics, Diffusivity, Optimization, Linear pro-
gramming, *Least squares method, Mathematical studies, Parametric hydrology,
Mathematics, Observation wells, Wells, Groundwater, Computer models, Aquifers.
Optimal identification of aquifer parameters in a distributed system was formu-
lated as an optimal control problem. The dynamics of the head was governed by
a second-order nonlinear partial differential equation. The numerical example
presented considers that the parameters to be identified were functions of the
space variable. Observations on head variations were available at several
observation wells distributed within the system. Spatial discretization was
first used to transform the distributed'system to a lumped system. The least
squares criterion function was then established. After introducing the Lag-
range multipliers, the maximum principle was applied to obtain the set of neces-
sary conditions that is optimal. These conditions were expressed in terms of
a set of canonic equations of two-point boundary value type that is easily
solved by the technique of quasi-linearization. Thus aquifer parameters were
directly identified on the basis of observational data taken at observation
stations. The maximum principle formulation is inherently more accurate and
stable, since it minimizes the least squares error, over the whole time and
space domains. Computationally, it is extremely efficient. The numerical
example presented demonstrates simultaneous identification of 11 parameters
defined at discretized points along the space variable. Quadratic convergence
was also demonstrated by numerical experimentation.
10
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74:02F-008
GALERKEN APPROXIMATION OF THE TIME DERIVATIVE IN THE FINITE ELEMENT ANALYSIS
OF GROUNDWATER FLOW,
Gray, W.G. and Finder, G.F.
Princeton University, New Jersey, Department of Civil and Geological Engineer-
ing.
Water Resources Research, Vol. 10, No. 4, p 821-828, August 1974. 6 fig, 2 tab,
12 ref.
Descriptors: *Finite element analysis, *Groundwater movement, Mathematical
models, Simulation analysis, Numerical analysis, Time series analysis.
The Galerkin method of approximation permits a high-order approximation in time
as well as in space in finite element analysis of groundwater movement. The
resulting approximate equations may successfully be solved by using a prismatic
element with triangular cross section. The time axis runs the length of the
prism and is subdivided into elements that may be linear, quadratic, or cubic.
Because this formulation requires in general the solution for several time
levels simultaneously, there is a resulting increase in computer time required
to solve the larger matrix. Numerical experiments indicate that the selection
of an optimum numerical scheme is dependent not only on the particular problem
considered but also on the sequence of time steps used.
74:02F-009
INTEGRODIFFERENTIAL EQUATIONS FOR SYSTEMS OF LEAKY AQUIFERS AND APPLICATIONS
2. ERROR ANALYSIS OF APPROXIMATE THEORIES,
Herrera, I.
Universidad Nacional Autonoma deMexico, Mexico City, Centre de Investigacion
en Matematicas Aplicadas y Sistemas.
Water Resources Research, Vol. 10, No. 4, p 811-820, August 1974. 2 fig, 1
tab, 17 ref, 1 append.
Descriptors: *Aquitards, Drawdown, Storage capacity, Permeability.
This paper is the second of a series devoted to developing a method of analysis
based on the integrodifferential equations of leaky aquifer systems. In part
1 (Herrera and Rodarte, 1973a) (W73-13378) the integrodifferential equations
were derived, and an interpretation for some of the approximate theories was
given in terms of the memory functions occurring in the equations. The same
equations are quite suitable for a systematic analysis of the errors involved,
and therefore in this paper they are used to carry it out.
74:02F-010
DRAWDOWN DISTRIBUTION DUE TO WELL FIELDS IN COUPLED LEAKY AQUIFERS, 1. INFINITE
AQUIFER SYSTEM,
Saleem, Z.A. and Jacob, C.E.
Illinois University, Chicago, Department of Geological Sciences.
Water Resources Research, Vol. 9, No. 6, p 1671-1678, December 1973. 1 fig,
14 ref.
Descriptors: *Drawdown, *Artesian aquifers, *Aquifer systems, Leakage, Math-
ematical studies, Equations, Aquifer characteristics, Confined water.
Solutions for drawdown distribution caused by the pumping of well fields in
single aquifers were obtained for a limited number of cases. However, most of
the aquifers in nature are not single isolated aquifers. Consequently, the use
of presently available solutions can yield unreasonable results. Equations
for the drawdown distribution caused by the pumping of well fields in two
11
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coupled leaky aquifers are presented. Two cases of the system are analyzed.
Case 1 is the upper aquifer when it is confined or unconfined and the drawdown
in it is very small in comparison with its 'saturated thickness; in case 2 the
drawdown in the upper unconfined aquifer can be significant. Approximate
solutions for relatively short and long times, as well as solutions for special
cases, are presented. The solutions involve integrals that can be evaluated
by using a digital computer.
74:02F-011
EFFECT OF PARTIAL PENETRATION ON FLOW IN UNCONFINED AQUIFERS CONSIDERING DE-
LAYED GRAVITY RESPONSE,
Neuman, S.P.
Agricultural Research Organization, Bet-Dagan, Israel, Institute of Soils and
Water.
Water Resources Research, Vol. 10, No. 2, p 303-312, April 1974. 7 fig, 28 ref.
Descriptors: *Groundwater movement, *Unsaturated flow. Water table. Water level
fluctuations, Pumping, Water yield, *Storage coefficient, Specific yield, Sim-
ulation analysis.
The delayed response process characterizing flow to a well in an unconfined
aquifer can be simulated by using constant values of specific storage and
specific yield without recourse to unsaturated flow theory. The theory is ex-
tended to account for the effect of a well partially penetrating a homogeneous
anisotropic unconfined aquifer. Field and laboratory evidence suggests that
the elastic storage properties of unconfined aquifers may often be much more
pronounced than those of deep-seated confined aquifers composed of similar
materials.
74:02F-012
MATHEMATICAL SIMULATION OF SUBSURFACE FLOW CONTRIBUTIONS TO SNOWMELT RUNOFF,
REYNOLDS CREEK WATERSHED, IDAHO,
Stephenson, G.R. and Freeze, R.A.
Agricultural Research Service, Boise, Idaho, Northwest Watershed Research
Center.
Water Resources Research, Vol. 10, No. 2, p 284-294, April 1974. 10 fig, 2
tab, 14 ref.
Descriptors: *Simulation analysis, *Subsurface runoff, *Snowmelt, Groundwater
movement, Soil water movement, Base flow, Snowpacks, Mathematical models,
*Idaho, Infiltration.
A mathematical model of subsurface flow complements a field study of snowmelt
runoff in a small upstream source area in the Reynolds Creek Experimental Water-
shed near Boise, Idaho. Field measurements from an instrumented cross section
of this small watershed show that the nechanism of streamflow generation is
subsurface delivery of meltwater over limited distances through shallow high-
permeability low-porosity formations of altered and fractured basalt. The math-
ematical model provides a two-dimensional transient saturated-unsaturated anal-
ysis of the subsurface flow at the field site. It was a valuable aid to a
unified interpretation of the field measurements. For mathematical models
that consist of boundary value problems with boundary conditions that are time
and space dependent, the boundary condition sensitivity can thwart the rational
calibration-validation procedure. This, together with the more serious limi-
tations of data availability, funds for data acquisition, and computer capacity,
precludes the imminent use of fully deterministic hydrologic response models
on larger basins or on a regional scale.
12
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74:02F-013
ANALYSIS OF UNSTEADY FLOW TOWARD ARTESIAN WELLS BY THREE-DIMENSIONAL FINITE
ELEMENTS,
Huang, Y.H. and Wu, S-J.
Kentucky Water Resources Research Institute, Lexington.
Water Resources Research, Vol. 10, No. 3, p 591-596, June 1974. 4 fig, 9 ref.
Descriptors: Anisotrophy, *Artesian wells, *Computer programs, *Computer models,
Aquifers, Digital computers, Drawdown, *Finite element analysis, Groundwater,
Heterogeneity, Numerical analysis, *Unsteady flow.
A three-dimensional finite element computer program was developed for analyzing
unsteady flow toward artesian wells. The program is designed especially for
determining the drawdown around an artesian well penetrating fully or partially
a nonhomogeneous and anisotropic aquifer and irregular shape and cross section.
It can also be used as a general program for aquifer simulation and evaluation.
A major advantage of the program lies in the minimum amount of input data re-
quired. By assuming the top and bottom boundaries of the aquifer as two arbi-
trary planes, the aquifer will be divided into six- or eight-node elements,
and their nodal coordinates generated automatically. The program was well
documented and can be used for solving complex problems encountered in practice.
Results indicate that unsteady flow toward artesian wells can be analyzed ef-
fectively by three-dimensional finite elements. A comparison between the finite
element and the exact mathematical solutions for a simple case shows that both
solutions check closely. The solution obtained from the computer program for
a complex case involving a nonhomogeneous aquifer was checked against that ob-
tained previously by the use of cylindrical elements, and both are found in
good agreement. The program was applied to a variety of cases, and reasonable
results were obtained.
74:02P-014
MATHEMATICAL MODELING OF WATER QUALITY FOR WATER RESOURCES MANAGEMENT, VOLUME
II: DEVELOPMENT OF HISTORIC DATA FOR THE VERIFICATION OF THE GROUND WATER
QUALITY MODEL OF THE SANTA CLARA-CALLEGUAS AREA, VENTURA COUNTY,
Hassan, A.A., Kleinecke, D.C., Johanson, S.J. and Pierchala, C.E.
California State Department of Water Resources, Sacramento.
Available from the National Technical Information Service, Springfield, Virginia
as PB-237 372. District Report, August 1974. 119 p, 35 fig, 25 tab, 25 ref.
Descriptors: California, *Dissolved solids, *Groundwater movement, *Water
quality, Model studies, Aquifers, *Mathematical models, Management, Data col-
lections, *Saline water intrusion, *Chlorides, Percolation, Water levels.
Based on the evaluation of total dissolved solids in wells of different depths,
vertical variation of quality was found to be insignificant in the Santa Clara-
Calleguas area, except in the Oxnard Plain area which has three separate aquifer
systems. In the Oxnard Plain area, the shallow perched aquifer was not modeled
in either the quantity or quality model. Leakage from the perched aquifer
served as an input to the upper layer nodes of the model. The Oxnard-Mugu
aquifer system and the Hueneme, Fox Canyon, and Grimes Canyon system were
modeled as separate layers of specific water quality values. The following
are the main conclusions of the sea water intrusion study: (1) Based on the
fluctuations of ground water levels and chloride concentrations in well water,
it was possible to construct cross sections showing the sequential advance in-
land of the sea water front into the Oxnard aquifer. (2) Generally, chloride
concentrations increased as water levels declined. (3) Sufficient data were
available in the Port Hueneme area to relate the inland advance of sea water
into the Oxnard aquifer to the decline in water levels. Data were insufficient
to develop the same relationship in the Point Mugu area. (4) Increase in the
13
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chloride concentration of groundwater in the Point Mugu area may be due to sea
water intrusion and also to percolation of saline water from the ground surface.
74:02P-015
MATHEMATICAL MODELING OF WATER QUALITY FOR WATER RESOURCES MANAGEMENT, VOLUME
I: DEVELOPMENT OF THE GROUNDWATER QUALITY MODEL,
Hassan, A.A., Kleinecke, D.C., Johanson, S.J. and Pierchala, C.E.
California State Department of Water Resources, Sacramento.
Available from the National Technical Information Service, Springfield, Virginia
as PB-237 371. District Report, August 1974. 191 p, 34 fig, 17 tab, 30 ref,
4 append.
Descriptors: *Dissolved solids, *Groundwater movement. Aquifers, *Groundwater
basins, Dispersion, *Salts, *California, *Computer programs, Mixing, *Model
studies. Computer models, *Saline water intrusion, Water utilization, Mathe-
matical models, Water quality. Management.
A digital computer program was developed to estimate the concentration of total
dissolved solids of extracted water from a multiaquifer groundwater basin. The
model considered salt input from natural sources and from man's uses of water:
domestic, industrial, and agricultural. The computer system was tested in the
Santa Clara-Calleguas area in Ventura County, California.
74:02F-016
WATER AND SALT TRANSFERS IN SUTTER BASIN, CALIFORNIA,
Tanji, K.K., Henderson, D.W., Sumant, G. , Iqbal, M. and Queck, A.F.
California University, Davis, Department of Water Science and Engineering
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 8 fig, 3 tab, 10 ref.
Descriptors: *Saline water intrusion, Salinity, Saline water, California,
Hydrogeology.
An analysis for water and salt transfers was carried in Sutter Basin, California.
The average drainage index for the hydrologic years 1964-72 was estimated to be
0.42 + 0.08 and the average salt balance index for the hydrologic years 1970-72
as 2.59 + 1.25. For the 1970 hydrologic year the flow-weighted average surface
input of salts (precipitation + irrigation water) was 0.1 tons per ac-ft and the
surface output (return flow) 0.7 tons per ac-ft. About 40% of the water and
70% of the salt load in the return flow is estimated to have originated from
subsurface origins, mainly rising connate water. Hydrogeologic evidence
indicates that connate water is rising upwards under artesian pressure from
about 2,500 to 3,000 ft below sea level. There is apparently no net deep
percolation of water and the net flux of water and salts is from the subsurface
to the land surface. This analysis shows that surface input-output relations
do not give an adequate assessment of water quantity-water quality in Sutter
Basin. When point source waste discharge permits are to be enforced in the
future, they should consider natural geochemical sources like rising connate
water in Sutter Basin.
74:02F-017
SIMULATION OF MISCIBLE DISPLACEMENT IN SOILS,
Smajstrla, A.G., Reddell, D.L. and Hiler, E.A.
Texas A&M University, College Station, Department of Agricultural Engineering.
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 9 fig, 27 ref, 1 append.
Descriptors: *Infiltration, *Soil water movement, Porous media, Computer pro-
grams, Simulation analysis, Model studies.
A simulation model was developed to simulate the miscible displacement of a con-
servative solute during one-dimensional vertical infiltration into a homogeneous,
14
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isotropic porous media. FORTRAN IV computer programs were written in a general
form so that various initial and boundary conditions could be specified as input
parameters. As a result of this research, the following conclusions were drawn:
1. Unsteady vertical infiltration, steady flow dispersion, and dispersion
during unsteady vertical infiltration into unsaturated, homogeneous, and isotrop-
ic porous media were accurately described by the simulation model; 2. The shape
of the solute distribution curve with depth is relatively insensitive to the
magnitude of the dispersion coefficient for porous media to which the functional
relationship used apply and for the range of pore water velocities commonly
encountered during infiltration into sand and clay loam soils; 3. Dispersion
coefficients are much larger and solute curve are very different for nonhomo-
geneous, anisotropic porous media than for homogeneous media. Data describing
the nonhomogeneous nature of soils will be needed to adequately describe
experimental field solute distribution curves.
74:02P-018
THE SHAPE OF THE INTERFACE IN STEADY FLOW IN A STRATIFIED AQUIFER,
Mualem, Y. and Bear, J.
Technion-Israel Institute of Technology, Haifa, Israel, Department of Civil
Engineering.
Water Resources Research, Vol. 10, No. 6, p 1207-1215, December 1974. 12 fig,
1 tab, 8 ref.
Descriptors: *Saline water-freshwater interfaces, Saline water, Saline water
intrusion, Freshwater, Aquifer 'systems, Aquifers, Aquifer characteristics,
Groundwater.
The present work deals with the shape of the interface in a coastal aquifer in
which a thin horizontal semipervious layer is present. Field observations and
laboratory experiments have shown that under these conditions a discontinuity in
the shape of the interface occurs such that a freshwater region exists under
the semipervious layer while immediately above it, saline (or mixed) water is
present in the aquifer. The paper presents an approximate solution for the
shape of the interface below the semipervious layer and for the extent of the
freshwater region above it under steady state conditions. The solution is based
on the Dupuit assumption and on a linearization of part of the flow equations.
74:02F-019
HYDROGEOCHEMISTRY OF CARBONATE GROUNDWATERS OF AN URBAN AREA,
Long, D.T. and Saleem, Z.A.
Illinois University, Chicago, Department of Geological Sciences.
Water Resources Research, Vol. 10, No. 6, p 1229-1238, December 1974. 4 fig,
5 tab, 29 ref.
Descriptors: *Groundwater, *Water quality, *Carbonates, Aquifer, Ions, Model
studies.
A comparison of the groundwater chemical data from the shallow dolomite aquifer
of Northeastern Illinois Metropolitan Area (NIMA) from August 1972 through
April 1973 with data collected 12-40 yr earlier indicates that concentrations of
all ions have increased, the greatest increase occurring in the southeastern
part of the area where the overburden is thinnest. The largest increases are
843, 142, and 91% in Cl(-), S04 (2-) , and Na(+), respectively. However, the spa-
tial distribution of the groundwater chemical types has remained the same with
time. The groundwater was found to be apparently supersaturated with respect to
calcite and dolomite; however, the two saturation indices were reduced by 20
and 30%, respectively, after considering the effect of ion pairings. The chemical
character of the groundwater is controlled, among other factors, by the change
of carbon dioxide content of the water along the groundwater flow path. A model
for the solution of dolomite based on the standard equations for carbonate equil-
ibrium is presented. The application of the model to the study area indicates
that a variety of geologic conditions between the dolomite aquifer and the over-
lying glacial drift prevail in the area.
15
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74:02F-020
THESIS EQUATION ANALYSIS OF RESIDUAL DRAWDOWN DATA,
Case, C.M., Pidcoe, W.W., and Fenske, P.R.
Nevada University, Reno, Center for Water Resources Research, Desert Research
Institute.
Water Resources Research, Vol. 10, No. 6, p 1253-1256, December 1974. 1 fig,
2 tab, 11 ref.
Descriptors: *Aquifer characteristics, Aquifer testing, Aquifers, Theis
equation, Transmissivity, Storage coefficient.
Equations are developed that allow the transmissivity and storage coefficient of
an aquifer to be determined from recovery data taken from an observation well
located at an arbitrary distance from the pumped well without the use of ante-
cedent drawdown data. The fundamental result is in the form of a series based
on the Theis recovery equation and up to the number of terms given is exact. The
assumptions of radial flow in a confined aquifer that is homogeneous, isotropic,
and semi-infinite, which are implicit in the Theis development, are, of course,
made in the current work as well. Two numerical examples using actual field
data are given.
74:02F-021
NITROGEN CONTENT OF SHALLOW GROUND WATER IN THE NORTH CAROLINA COASTAL PLAIN,
Gilliam, J.W., Daniels, R.B., and Lutz, J.F.
North Carolina State University, Department of Soil Science.
Journal of Environmental Quality, Vol. 3, No. 2, p 147-151, April-June, 1974.
2 fig, 2 tab, 14 ref.
(See 74:058-054)
16
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Section VI
WATER CYCLE
WATER IN SOILS (GROUP 02G)
74:020-001
APPROXIMATING SOIL MOISTURE CHARACTERISTICS PROM LIMITED DATA: EMPIRICAL
EVIDENCE AND TENTATIVE MODEL,
McQueen, I.S. and Miller, R.F.
Geological Survey, Denver, Colorado, Water Resources Division
Water Resources Research, Vol. 10, No. 3, p 521-527, June 1974. 6 fig, 43 ref.
Descriptors: *Soil moisture, *Moisture content, Adsorption, Capillary action,
Equations, Moisture tension, *Moisture stress.
The soil moisture characteristic can be approximated from limited data as a
composite of segments that are simple logarithmic relations. From available
data, three segments are evident: (1) a capillary segment from saturation
to pF 2.5, (2) an absorbed film segment covering the stress range from about
pF 2.5 to about 5.0, and (3) a tightly absorbed segment that extends from PF
5 • 0 to 7 • 0»
74:02G-002
DETERMINATION OF DISPERSION AND NONLINEAR ADSORPTION PARAMETERS FOR FLOW IN
POROUS MEDIA,
Gupta, S.P. and Greenkorn, R.A.
Purdue University, Lafayette, Indiana, School of Chemical Engineering
Vo1* 10' No- 4' P 839-846, August 1974, 10 fig, 3
Descriptors: *Dispersion, *Adsorption, *Porous media, Groundwater movement,
Permeability, Isotherms, Nitrates, Phosphates.
Ottawa washed sand mixed with 0.0-7.5% kaolin clay was used to determine dis-
persion and nonlinear adsorption parameters during flow through porous media
The ions considered were nitrate for the nonadsorbing species and phosphate for
the adsorbing species. A one-dimensional linear model with a longitudinal dis-
persion coefficient was used, and the dispersion coefficient was determined by
least squares fit. The dispersion coefficients were correlated with disper-
sivity models based on kinematic viscosity and powers of velocity and Reynolds
number. The velocity exponent seemed independent of clay content, whereas the
model coefficients increased approximately linearly with clay content The
static adsorption data suggest a Freundlich isotherm. The principle of linear
superposition was assumed for dispersion and adsorption to estimate the dynamic
parameters. The adsorption parameter for the linear model was approximately
linear with clay content. The two adsorption parameters for the nonlinear
model were highly correlated and cannot be estimated simultaneously from dy-
namic measurements alone. The linear model described the movement of phos-
phate ions adequately for the medium considered. However, for a natural system
in which clay content is high and phosphate ion concentration is low one would
expect better data from the generalized nonlinear model.
74:02G-003
TWO-DIMENSIONAL SEEPAGE IN LAYERED SOIL-DESTABILIZING EFFECTS OF FLOWS WITH AN
UNSTEADY FREE SURFACE,
Dicker, D. and Babu, O.K.
17
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New York State University, Stony Brook.
Water Resources Research, Vol. 10, No. 4, p 801-809, August 1974. 5 fig, 8
ref, 1 append.
Descriptors: *Soil stability, *Seepage, *Unsteady flow, *Free surface, land-
slides, Groundwater, Soil pressure, Soil water, Soil water movement, Soil mois-
ture, Soil investigations, Soil mechanics, Soil properties, Mathematical studies,
Mathematics, Mathematical models.
An analytic study was made about the destabilizing effects of a prolonged rain-
fall over the sides of a long symmetric hill. The assumptions underlying the
analysis were (1) the soil consisted of layers parallel to the hills lope, (2)
the flow domain was bounded from below by an unknown free surface, and (3) this
free boundary moves downward with passage of time. The resulting flow pattern
was therefore time dependent. The motion is described by Darcy's law as applied
to a saturated porous medium having variable conductivity. Perturbation tech-
niques were applied in constructing the solution to this nonlinear problem.
For certain portions of the flow region the pertubation becomes singular, and
the singularities were removed by the methods of matched asymptotic expansions.
Properties of singular integrals with Cauchy kernels were employed in certain
quantitative estimates. Only the first-order effects are presented here. It
was shown that one large-time effect of prolonged rainfall is to generate out-
ward horizontal velocity components in the distant regions of the slope; these
components grow in time. It is known in soil mechanics that such tendencies
to outward flow have serious destabilizing effects on the soil slope. This
paper demonstrates that the underlying causes for such disasters as landslides
can be traced in a significant fashion to the hydrodynamic nature of the seep-
age that evolves naturally as a result of prolonged rainfall.
74:020-004
SEEPAGE THROUGH A HILLSIDE: THE STEADY WATER TABLE,
Warrick, A.W. and Lomen, D.O.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Water Resources Research, Vol. 10, No. 2, p 279-283, April 1974. 3 fig, 1 tab,
12 ref.
Descriptors: *Seepage, *Groundwater movement, *Water table, Mathematical studies,
Slopes, Topography, Hydraulic conductivity.
An analytical solution is given for seepage through a hillside in which a curved
water table is maintained by steady percolating water. The two-dimensional
surface is assumed to be a straight slope from the base to a seepage point but
may be irregular at higher elevations. Conferma1 transformations determine
seepage elevations and water table profiles as a function of the seepage rate
and the slope. For small slopes and small percolation rates the seepage ele-
vation is equal to the rainfall rate times the width of the slope divided by
the saturated hydraulic conductivity.
74:026-005
SALT DISPLACEMENT INTO DRAIN TILES UNDER PONDED LEACHING,
Miyamoto, S. and Warrick, A.W.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Water Resources Research, Vol. 10, No. 2, p 275-278, April 1974. 6 fig, 1 tab,
7 ref.
Descriptors: *Leaching, *Soil water movement, *Tile drainage, Infiltration,
Mathematical models. Saturated flow, Saline water, Path of pollutants.
18
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Steady state piston-type displacement into drain tiles when the ground surface
is partially covered by an impermeable material or by ponded water away from
the drains was analyzed mathematically. By preventing the water from infil-
trating directly over the drains a more uniform leaching pattern is attained.
Hie result is to reduce the water required for leaching to the depth of drains
by as much as one half. Experimental data obtained from sand tank models sup-
port this prediction
74t02G-006
ANION EXCLUSION AND COUPLING EFFECTS IN NONSTEADY TRANSPORT THROUGH UNSATURATED
SOILS: II. LABORATORY AND NUMERICAL EXPERIMENTS,
Bresler, E. and Laufer, A.
Agricultural Research Organization, Bet-Dagan, Israel, Department of Soil
Physics,
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 213-218, March-
April 1974. 8 fig, 1 tab, 11 ref.
Descriptors: *Ion transport, *Leaching, *Soil water movement. Osmosis, Dis-
persion, Convection, Ion exchange, Chlorides, Mathematical models, Numerical
analysis.
A numerical model for the simultaneous transport of anions and water was com-
pared with measured chloride and water flow data. Laboratory soil-column ex-
periments were conducted under conditions of infiltration, redistribution, and
evaporation of water in the upper part of the soil profile. The effects of
convection, ionic diffusion, mechanical dispersion, anion exclusion and water
flow in response to salt concentration gradients were considered jointly.
The agreement between theory and experiment, as expressed by flow into and out
of the soil-column and by water content and salt distribution profiles, was
generally good. The results were relatively insensitive to anion exclusion and
osmotic effects. Estimates of dispersivity as obtained from miscible displace-
ment experiments were sufficient for prediction. For the conditions studied,
osmotic gradients and anion exclusion effects are of minor importance.
74:020-007
SOIL WATER CONTENT: MICROWAVE OVEN METHOD,
Miller, R.J., Smith, R.B., and Biggar, J.W.
California University, Davis, Department of Water Science and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 535-537, May-
June 1974. 2 fig, 3 tab, 6 ref.
Descriptors: *Moisture content, *Soil moisture, *Microwaves, *Drying, Lab-
oratory tests.
The moisture content of soils may be determined rapidly with a microwave tech-
nique. Equations are given for estimating soil drying times for two soils of
different texture at different moisture contents and for different sample sizes.
Drying soil by microwave oven may also be useful as a method for soil prep-
aration prior to chemical analyses.
74:020-008
INFLUENCE OF ANTECEDENT SOIL MOISTURE SUCTION ON SATURATED HYDRAULIC CONDUCTIV-
ITY OF SOILS,
Gerard, C.J.
Texas Agricultural Experiment Station, Weslaco.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 506-509, May-
June 1974. 6 fig, 4 tab, 5 ref.
19
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Descriptors: *Hydraulic conductivity, *Antecedent moisture content, *Soil
water movement, *Moisture tension, Saturated flow, Soil gases, Carbon dioxide,
Wetting.
The influence of antecedent soil moisture suction on saturated hydraulic con-
ductivities of soils was studied. Saturated hydraulic conductivity of a soil
is a dynamic property which is markedly influenced by antecedent soil moisture
suction. Antecedent soil moisture of 0.33 bar suction, such as is often prac-
ticed with trickle irrigation, caused marked reduction in the ability of soil
to conduct of water. Gases produced by microorganisms as low suction, their
subsequent entrapment, and their influence on soil macrovoids are largely
responsible for reduction in ability of soil to conduct water. Reduction of
effective soil macrovoids by microbial growth, flowing water, and soil moisture
suction can also reduce soil permeability. Soil moisture management can in-
fluence the ability of soil to conduct water.
74:02G-009
TIME-DEPENDENT LINEARIZED INFILTRATION. I. POINT SOURCES,
Warrick, A.w.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 383-386, May-
June 1974. 4 fig, 12 ref.
Descriptors: *Soil water movement, *Infiltration, *Unsaturated flow, Equations,
Soil moisture, Wetting, Irrigation.
Soil water flow from a point source as analyzed using a linearized form of the
moisture flow equation. Time-dependence was assumed with the results simpli-
fying to those for steady-state conditions. Discrete time-distributed inputs
such as for trickle or high frequency irrigation are amenable to solution.
Numerical simulations include the advance of a wetting front during infiltra-
tion, moisture variation resulting from a cyclic input as during irrigation,
and the matric flux potential field for a two-source problem.
74:02G-010
MEASUREMENT OF HYDRAULIC CONDUCTIVITY BY MEANS OF STEADY, SPHERICALLY SYMMETRIC
FLOWS,
Dirksen, C.
Agricultural Research service, Madison, Wisconsin, Soil and Water Conservation
Research Division.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 3-8, January-
February 1974. 5 fig, 1 tab, 20 ref.
Descriptors: *Hydraulic conductivity, *Unsaturated flow, *Tensiometers, *Soil
water movement, Instrumentation, Tension, Infiltration, Percolation, Pressure
head, Moisture content.
The dependence of hydraulic conductivity upon pressure head can be determined
from a series of steady, spherically symmetric flows: at any point the hydraulic
conductivity is equal to the rate of change of the steady flux per unit solid
angle with respect to the pressure head of that point, divided by its radial
distance from the center of the water source. This method is useful for in-
situ measurements in the field because it requires only one controlled boundary
condition, and does not require one-dimensional flow. Hydraulic conductivity
values derived from the pressure head in the source cavity in field tests were
the same as those derived from tensiometer measurements near the source. A
range of hydraulic conductivity values can be obtained faster with a series of
different, steady pressure heads in the source cavity, rather than by measure-
20
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ments on a series of tensiometers located at several distances from the source.
Gravity tends to distort the spherical symmetry of the flow. For most soils
the effect of gravity near the cavity is small enough to obtain satisfactory
hydraulic conductivity values. Gravity has no effect on the pressure head
distribution directly below the cavity, suggesting that this is a preferred
location for tensiometers. The analytical solution obtains the hydraulic
conductivity in an exact manner for any position. The radius of the cavity
should be kept as small as possible.
74:02G-011
FLUX-GRADIENT RELATIONSHIPS AND SOIL-WATER DIFFUSIVITY FROM CURVES OF WATER
CONTENT VERSUS TIME,
Nofziger, D.L., Ahuja, L.R. and Swartzendruber, D.
Purdue University, Lafayette, Indiana, Department of Agronomy.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 17-23, January-
February 1974. 6 fig, 11 ref.
Descriptors: *Soil water movement, *Unsaturated flow, Seepage, Percolation,
Equations, Wetting, *Diffusivity, Diffusion.
Direct analysis of a family of curves of soil-water content versus time at
different fixed positions enables assessment of the flux-gradient relationship
prior to the calculation of soil-water diffusivity. The method was evaluated
on both smooth and random-error data generated from the solution of the hori-
zontal soil-water intake problem with a known diffusivity function. Inter-
polation, differentiation, and integration were carried out by least-squares
curve fitting based on the two recently developed techniques of parabolic
splines and sliding parabolas. Results were excellent for both smooth and
random-error input data, whether in terms of recovering the original known
diffusivity function, assessing the nature of the flux-gradient relationship,
or in making the numerous checks and validations at various intermediate stages
of computation. The method applies for any horizontal soil-wetting process
independently of the specific boundary conditions, including water entry through
a nonzero inlet resistance. It should be adaptable to horizontal dewatering,
and extendable to vertical flow.
74:020-012
GAMMA RADIATION MEASUREMENTS OF BULK DENSITY CHANGES IN A SOIL PEDON FOLLOWING
IRRIGATION,
Reginato, R.J.
Agricultural Research Service, Phoenix, Arizona, Water Conservation Laboratory.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 24-29, January-
February 1974. 3 fig, 4 tab, 14 ref.
Descriptors: *Bulk density, *Expansive soils, *Nuclear moisture meters, Gamma
rays, Irrigation effects, Soil physical properties.
Bulk density in a soil pedon was measured with a gamma-ray transmission tech-
nique utilizing Cs-137 and Am-241. Both gamma-ray sources could not be used
simultaneously. By alternating sources for each scan down the soil profile,
bulk density was found to decrease in the top 6 cm of soil about 30 minutes
after water was ponded on the soil surface. As soon as the water drained
from the surface, bulk density values approached preirrigation levels. Changes
in height of the soil surface upon irrigation corresponded with changes in
bulk density.
21
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74:020-013
THERMODYNAMICS OF ION EXCHANGE,
Ravina, I. and DeBock, J.
Technion - Israel Institute of Technology, Haifa, Department of Agricultural
Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 45-49, January-
February 1974. 2 tab, 13 ref.
Descriptors: *Ion exchange, *Clays, *Water chemistry, Thermodynamics, Sorption,
Cation exchange, Chemical potential, lonization, Free energy.
A local formulation of nonequilibrium thermodynamics was used to define the
electrochemical potentials in the ion-clay-water system, thus enabling develop-
ment of an improved nonempirical approach to cation-exchange processes. The
presence of the electrical field in the system is expressed by a proportional
increase of the pressure in the double layer. The effect of the electrical
field on the chemical potentials of the exchangeable cations is divided into
the common electrostatic term and a term dependent on their polarizabilities.
For systems containing a mixture of monovalent ions the electrostatic effect
of the electrical field is the same for each of the exchangeable cations.
Using values of the polarizabilities and intrinsic volumes of the alkali metal
cations, the free energies of exchange with sodium in montmorillonite were
calculated. The calculated free energies were in good agreement with experi-
mental values.
74:020-014
SUBSURFACE DRAINAGE SOLUTIONS BY GALERKIN'S METHOD,
Dass, P. and Morel-seytoux, H.J.
Colorado State University, Fort Collins, Department of Civil Engineering.
Proceedings of ASCE, Journal of the Irrigation and Drainage Division, Vol. 100,
No. IR1, Proc Paper 10397, March 1974, p 1-15, 8 fig, 1 tab, 15 ref.
Descriptors: *Aquifers, Water table, *Drainage, *Subsurface drainage, Method-
ology, *Design Criteria.
For the solution of drainage problems a linearized form of Boussinesq's equa-
tion is often used. To improve the design, higher order approximations have
been used. A variation of Galerkin's method is used to solve the nonlinear
Boussinesq equation. By comparison it is found that the linearized method,
when the drawdown to aquifer depth ratio, H/d, becomes large, provides too
optimistic designs. The design criteria based on the linearized Boussinesq
equation overestimates the rate of drainage for two reasons: (1) They do not
account for important nonlinear effects; and (2) they do not account for the
delaying effect of the unsaturated flow condition above the water table. The
use of Galerkin's method makes it possible to account for the nonlinear effect
which is quite significant.
74:020-015
DERIVATION OF AN EQUATION OF INFILTRATION,
Morel-seytoux, H.J. and Khanji, J.
Universite Scientifique et Medicale de Grenoble (France), Institute de Mecani-
que.
Water Resources Research, Vol. 10, No. 4, p 795-800, August 1974. 3 fig, 1 tab,
15 ref.
Descriptors: *Infiltration rates, *Unsaturated flow, *Capillary conductivity,
*Permeability, Percolation, Hydraulic conductivity.
22
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A precise physical meaning was shown for the emperical parameters developed
by Green and Arapt (1911)• The functional relation between the effective capil-
lary head and the initial water content was obtained. In addition, it was
shown that Green and Ampt's assumption of a front separating a saturated zone
from the zone at the initial water content can lead to errors of prediction
of 10-70 percent. The formulas developed are both simple and accurate and of
practical value to the hydrologist.
74:02G-016
A PREDICTOR-CORRECTOR METHOD FOR SOLVING THE CONVECTION-DISPERSION EQUATION FOR
ADSORPTION IN POROUS MEDIA,
Tagamets, T. and Sternberg, Y.M.
Maryland University, College Park, Department of Civil Engineering.
Water Resources Research, Vol 10, No 5, p 1003-1011, October 1974, 9 fig, 23 ref.
Descriptors: *Adsorption, *Convection, *Dispersion, Numerical analysis, Fluid
movement, Porous media, Saturated flow, Equations, Mathematical models, Mass
transfer, Isotherms, Finite element analysis.
The on-dimensional convection-dispersion equation subject to a nonlinear
adsorption isotherm was formulated and solved by using a predictor-corrector
finite difference scheme. The effects of convection, dispersion, and adsorption
were illustrated for some typical values of variable encountered in 'real sys-
tems'. A comparison between the numerical results and some experimental data
was also presented.
74:02G-017
A COUPLED HEAT AND MOISTURE TRANSPORT MODEL FOR ARCTIC SOILS,
Guymon, G.L. and Luthin, J.N.
Alaska University, College, Institute of Water Resources.
Water Resources Research, Vol. 10, No. 5, p 995-1001, October 1974. 1 fig, 27
ref.
Descriptors: *Arctic, *Permafrost, *Soil moisture, *Soil water movement,
*Thermal properties, *Frozen soils, Alaska, Thawing, Freezing, Tundra, Hydraulic
conductivity, Frost heaving, Darcys law, Conduction, Computer models, Equations,
Numerical analysis.
The thermal and moisture regimes of arctic and subarctic soils act in parallel
in a complex manner and must be considered together. The problem of moisture
movement and storage in these soils is complicated by water undergoing a phase
change during freezing and thawing and by the presence of ice-rich permafrost.
A one-dimensional model of these processes was developed based on an equivalent
quasi-linear variational functional for the Richards equation and the heat con-
duction equation including convective components. The variational functional
was solved by a finite element analog. Convergence and stability were investi-
gated, and it was concluded that the numerical procedure is convergent and
stable in general.
74:02G-018
PERMEABILITY OF UNSATURATED FIELD SOILS CALCULATED FROM LABORATORY DESATURATION
DATA,
Sinclair, L.R., Fitzsimmons, D.W. and Bloomsburg, G.L.
Florida University, Sanford, Agricultural Research and Education Center.
Transactions of the American Society of Civil Engineers, Vol. 17, No. 3, p 399-
405, May-June 1974. 11 fig, 1 tab, 26 ref.
Descriptors: *Porous media, *Permeability, *Unsaturated flow, *Laboratory tests,
Soil water, Capillary water, Soils, Agriculture, Soil tests, Hydraulic con-
ductivity, Pervious soils, Pores, Soil water movement, Porosity, Testing pro-
cedures.
A method of calculating the permeability of partially saturated field soils from
experimentally determined capillary pressure head-saturation relationships
23
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developed. The method involved the use of a Burdine-type equation to calculate
the relative permeability values which were expressed as a function of average
values of the square of the pore radius calculated from the pore-size distribu-
tion of the soil using a statistical approach. The pore-size distribution was
determined from the capillary pressure head-saturation relationship for the soil.
The method was evaluated by comparing experimental capillary pressure head-
permeability relationships for seven soils with similar relationships calculated
from experimentally determined capillary pressure head-saturation relationships.
These comparisons were made with relationships obtained for both disturbed and
undisturbed samples of each soil. In general, the calculated relationships com-
pared favorably with the experimentally determined relationships. Very close
agreement was found between experimental and calculated capillary pressure head-
permeability relationships when the data were scaled by d ividing permeability
and capillary pressure head values by the saturated permeability and bubbling
pressure head of the soil, respectively. When the data were scaled in this way,
the capillary pressure head-permeability relationships calculated for both un-
disturbed and disturbed samples of a soil were essentially the same.
74:02G-019
PROCEEDINGS OF THE SECOND INTERNATIONAL DRIP IRRIGATION CONGRESS,
Second International Drip Irrigation Congress,
California University and United States Department of Agriculture, Agriculture
Research Service.
Second International Drip Irrigation Congress, July 7-14, 1974, San Diego,
California.
(See 74:03F-006)
74:020-020
HIGH ELECTROLYTE WATER FOR RECLAIMING SLOWLY PERMEABLE SOILS,
Rahman, M.A., Hiler, E.A., and Runkles, J.R.
Texas A&M University, College Station.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 1,
p 129-132, January-February 1974. 7 fig, 2 tab, 11 ref.
Descriptors: *Infiltration, *Infiltration rates, *Hydraulic conductivity.
Electrolytes, Soil investigations, Soil management, Soil physical properties,
Soil treatment. Soil water movement, Permeability, Agriculture.
Reclamation processes in a slowly permeable, mildly sodic, low electrolyte,
humid soil were studied using different ionic compositions and concentrations
of electrolyte waters. The method utilized for this soil consisted of increasing
soil hydraulic conductivity with additions in increasing concentration of
electrolyte water and then leaching out salts with decreasing concentrations
while maintaining the increased hydraulic conductivity, it can be concluded
that electrolyte waters applied in increasing followed by decreasing concentra-
tions were utilized successfully for reclaiming this soil. The soil intake
rates and hydraulic conductivities were increased very substantially. Further
applied research and field trials with similar soils seem justified based on
the findings.
74:02G-021
POWDERED METAL PLATES FOR CONSTRUCTING UNSATURATED FLOW CELLS,
Bianchi, W.C.
United States Department of Agriculture, Agricultural Research Service, Fresno,
California, Water Management Research.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 683-684, July-
August, 1974. 3 fig, 1 tab, 4 ref.
Descriptors: *Unsaturated flow, Flow measurement, Groundwater recharge,
Groundwater movement.
24
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Described is the theoretical design, construction and observed characteristics
of sintered stainless steel powdered metal plates which could be used in control
sections of an unsaturated flow cell.
74:026-022
SMALL TENSIOMETERS FOR FIELD AND LABORATORY STUDIES,
Rogers, J.S.
United States Department of Agriculture, Agricultural Research Service, Gaines-
ville, Flordia.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 690-691, July-
August, 1974. 1 fig.
Descriptors: *Tensiometers, Laboratory equipment, Soil moisture, Soil water,
Soil investigations.
A small tensiometer was constructed and used in field and laboratory studies.
The units are suitable only for low suctions, but have the fast response time
that is desirable for measuring short-term changes in 'field and laboratory
studies of drainage. Several tensiometers have been in use for over 4 years
and continue to perform very satisfactorily.
74:020-023
DETERMINING EFFECTIVE SOIL WATER DIFFUSIVITIES FROM ONE-STEP OUTFLOW EXPERIMENTS,
Gupta, S.C., Farrell, D.A., and Larson, W.E.
Minnesota University, St. Paul.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 710-716,
September-October, 1974. 7 fig, 15 ref. append.
Descriptors: Diffusivity, Methodooogy, Soil water, Soil water movement, Soil
properties, Computers.
A method is developed whereby effective or weighted mean diffusivlty, D, can
be estimated by using outflow data. These estimates can further be analyzed
for soil water diffusivity, D theta, with the help of a step-wise function and
the relationship given by Crank (1956). The suggested procedure for estimating
soil water diffusivity is more accurate than previous methods because no assump-
tion of constant diffusivity either over the pressure increment or over the
length of the soil core is required. Moreover, the procedure does not use the
early part of the outflow curve and thus reduces the effect of membrane impedance
on the estimates of D theta. The method was tested by simulating outflow ex-
periments on a digital computer, and using data obtained to calculate-diffusiv-
ities. Our estimates of diffusivity were in better agreement with the actual
diffusivities than those obtained with the earlier "one-step" method.
74:020-024
UNSATURATED HYDRAULIC CONDUCTIVITY FROM CUMULATIVE INFLOW DATA,
Ahuja, L.R.
Hawaii University, Honolulu, Department of A,ronomy and Soil Science.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 695-699,
September-October, 1974. 6 fig, 13 ref.
Descriptors: *Hydraulic conductivity, Infiltration, Diffusivity, Soil properties.
A method of determining the wetting-phase unsaturated hydraulic conductivity K
theta from the data of cululative inflow into a uniform soil core when water
enters through a porous plate of high hydraulic resistance is described and
evaluated. The method is based on piecewise application of the Green and Ampt
(1911) approach to the above process of infiltration. The K theta determined
by this technique from the numerical-solution inflow data of Yolo light clay
were within 20% of the K theta values actually used in obtaining the numerical
solution in two different cases of hydraulic resistance. Similar analysis of
the experimental inflow data of Salkum silty clay loam for four different
hydraulic resistances yielded the K theta data which closely agreed with the
K theta values determined by detailed analysis of the soil-water content
transients.
25
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74:02G-025
STEADY FLOWS OF WATER AND SALT IN UNIFORM SOIL PROFILES WITH PLANT ROOTS,
Raats, P.A.C.
U.S. Salinity Laboratory, Riverside, California.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 717-722,
September-October, 1974. 8 fig, 20 ref.
Descriptors: *Soil water movement. Root system, Root zone, Pressure head,
Hudraulic conductivity, Soil-water-plant relationships.
Steady upward and downward flows of water in the presence of uptake of water
by plant roots are analyzed. Qualitative features of possible pressure head,
total head, and water content profiles for steady conditions are discussed.
Specific calculations are based upon an exponential increase of the hydraulic
conductivity with the pressure head and an exponential decrease of the rate of
uptake with depth. For downward flows, the distribution of the raatric flux
potential can be expressed as a function of the rate of infiltration, the leach-
ing fraction, and two parameters cahracterizing the soil and the uptake distri-
bution, respectively. Although the water content on the root zone may be nearly
uniform, the matric component of the flux may be significant. For upward flows,
the distribution of the matric flux potential can be expressed as a function
of the rate of infiltration, the rate of transpiration, the hydraulic conduct-
ivity of the saturated soil and the same two parameters characterizing the
soil and the uptake distribution. The depth at which the flux vanishes, the
minimum value of the matric flux potential for a given depth of the water
table, and the maximum depth of the water table are evaluated. Finally, neglect-
ing the effects of salt precipitation and dissolution and of diffusion and dis-
persion, the distribution of salts associated with the steady downward flows
is evaluated.
74:02G- 026
TWO-DIMENSIONAL DISPLACEMENT INTO OR FROM WATER-FliLED DITCHES,
Miyamoto, S. and Warrick, A.W.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 723-726,
September-October, 1974. 5 fig, 1 tab, 11 ref, append.
Descriptors: Soil water movement, Leaching, Drainage water, Water quality,
Daline water intrusion, Fertilizers.
Piston-type displacement of solutes for steady-state saturated flow into or
from water-filled ditches is analyzed mathematically and by a sand-tank model.
The displacement front onto the drains advances much faster near the drains
than in the region midway between them. The presence of an impermeable sublayer
accentuates this trend. The front becomes nearly horizontal for a wider surface
impermeable spoil bank or if water is ponded away from the drains. Such a
spoil bank may be useful for reducing the amount of water required to leach
salts or for minimizing the loss of water-applied fertilizers into drains.
The displacement front for water moving from the ditches into a field (such as
for salt intrusion from open ditches) advances in an ellipsoidal pattern. The
analysis is also useful for prediction the displacement patterns for localized
initial solute distributions. Experimental data obtained from a sand-tank
model agree with the predicted fronts.
74:02G-027
CHLORIDE AND TRITIATED WATER FLOW IN DISTURBED AND UNDISTURBED SOIL CORES,
McMahon, M.A. and Thomas, G.W.
Kentucky University, Lexington, Department of Agronomy.
Soil science Society of America Proceedings, Vol. 38, No. 5, p 727-732,
September-October, 1974. 6 fig, 4 tab, 13 ref.
Descriptors: Soil water movement,' Soil properties, Water chemistry, Chlorides,
Nitrates, Soil investigations, Soil physics, Anions.
Columns of disturbed and undisturbed Eden, Maury, and Pembroke soils were .
eluded with CaC12 in tritiated water. The chloride was used as a substitute
26
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for nitrate since it is not affected biologically. The experiments were carried
out to investigate the effects of natural soil structure on the flow of water
and chloride. In all three soils flow was less stable In the undisturbed cores
Budging from the shape of the curve and the points of initial tritiated water
and chloride breakthrough. Chloride moved through the undisturbed Eden and
Maury soils faster than through the disturbed columns. Both soils exclude
anions to a significant extent. In the Pembroke soil, which adsorbs anions,
the chloride was retarded in the undisturbed column as compared to the disturbed
column. The results suggest that field movement fo water and anions is not
described very well by columns of disturbed, packed soils.
74:020-028
TWO-DIMENSIONAL WATER INFILTRATION FROM A TRENCH IN UNSATURATED SOILS,
Sawhney, B.L. and Parlange, J.-Y.
Connecticut Agricultural Experiment Station, New Haven.
Soil Science Society of Amercia Proceedings, Vol. 38, No. 6, p 867-871,
November-December, 1974. 8 fig, 2 tab, 10 ref.
(See 74:03F-137)
74:020-029
DETERMINATION OF WETTING FRONT SUCTION IN THE GREEN-AMPT EQUATION,
Mein, R.G. and Farrell, D.A.
Monash University, Victoria, Australia.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 872-876,
November-December, 1974. 3 fig, 4 tab, 10 ref.
Descriptors: *Infiltration, Theoretical analysis, Hydraulic conductivity,
Capillary action, Soil water movement, Wetting, Soil water, Soil investigations.
Interest in the Green-Ampt equation to predict infiltration rates into uniform
and layered soils has increased in recent years. The work reported here is a
study of the theoretical justification of determining the suction (at the wet-
ting front) parameter in the equation from the hydraulic conductivity versus
capillary suction relationship for the soil. It is shown that the wetting
from suction so determined and used in a form of the Green-Ampt equation which
allows for the surface boundary condition initially being one of constant flux
gives predictions of infiltration volumes comparable to those determined by
numerical solution of the complex partial-differential equation of moisture
flow.
74:020-030
NOMOGRAPHIC INTERPRETATION OF WATER ABSORPTION DATA IN TERMS OF A TWO-PARAMETRIC
DIFFUSIVITY-WATER CONTENT FUNCTION,
Stroosnijder, L. and Bolt, G.H.
State Agricultural University, Wageningen, The Netherlands, Dept. of Soils and
Fertilizers.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 876-880,
November-December, 1974. 5 fig, 2 tab, 13 ref.
Descriptors: Diffusivity, Moisture content, Wetting.
An exponential extrapolation of a set of experimentally determined diffusivities,
D as a function of water content, theta, into the region near saturation lead
to an underestimate of the water absorption. A two-parametric expression for
the diffisivity as a function of theta, as proposed by Ahuja et al. (1972), is
used to construct a nomogram. This provides a connection between the standard-
ized D-theta relationships according to Ahuja et al. and certain "integral"
properties of the absorption wetting process viz. the sorptivity and a shape
factor of the wetting front. Good agreement is obtained between experimentally
determined diffusivity values and the values derived from the nomographical
interpretation of water absorption data. The present approach also lends itself
to the construction of families of scaled wetting curves. Thus absorption
behavior for different (uniform) initial moisture contents could be predicted
adequately.
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74:02G-031
UNSTEADY, UNSATURATED, N-DIMENSIONAL MOISTURE FLOW IN SOIL: A COMPUTER
SIMULATION PROGRAM,
Van der Ploeg, R.R. and Benecke, P.
Georg-August University, Goettingen, West Germany.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 881-884,
November-December, 1974. 7 fig, 1 tab, 15 ref.
(See 74:03F-139)
74:02G-032
LIMITATIONS OF THE INSTANTANEOUS PROFILE METHOD FOR FIELD MEASUREMENT OF
UNSATURATED HYDRAULIC CONDUCTIVITY,
Baker, F.G., Veneman, P.L.M., and Bouma, J.
Wisconsin University, Madison, Department of Soil Science.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 885-888,
November-December, 1974. 4 fig, 13 ref.
Descriptors: *Hydraulic conductivity, Soil water movement, Tensiometer,
Moisture content, Soil water, Soil tests, Soil investigations.
Technical problems and soil profile characteristics may limit the applicability
of the instantaneous profile method for field measurement of unsaturated hydraul-
ic conductivities. A modified procedure for tensiometer installation and
different methods for measuring moisture contents are discussed. Good agree-
ment was found between moisture contents determined in situ with the neutron-
probe and those indirectly derived from moisture retention curves obtained
from measurements of large core samples in a closed assembly. Sloping soils
with slowly permeable horizons or with lateral water movement cannot be
characterized adequately with this method. The use of the crust test procedure
is recommended.
74:02G-033
KINETIC AND EQUILIBRIUM STUDIES OF BORON DESORPTION FROM SOIL,
Griffin, R.A. and Burau, E.G.
California University, Davis, Department of Soils and Plant Nutrition.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 892-897,
November-December, 1974. 6 fig, 2 tab, 19 ref.
Descriptors: *Boron, Adsorption Kinetics, Soil Texture, Soil chemistry, Soil
tests, Soil investigations.
Kinetics of boron desorption from soil were determined using 0.05M manitol
solutions to create pseudo first-order reaction conditions. The results showed
two separate pseudo first-order reactions and one very slow reaction for which
detailed kinetic treatment was not attempted. The relative amount of boron
associated with the two fast reactions was indepdendent of soil texture and of
initial sample boron content. It was postulated that the two reaction rates
were due to desorption from two independent boron retention sites. It was
speculated that the two fast reactions were due to desorption from hydroxy
iron, magnesium, and aluminum materials in the clay fraction. The third or
slowest reaction rate was probably due to diffusion of boron from the interior
of clay minerals to solution phase. Equilibrium studies showed that boron
desorption followed a 2-site analog of a linear form of a 1-site Langmuir
expression. Langmuir adsorption maximum values for each site corroborated
those calculated from the kinetic study and supported the multisite interpreta-
tion of the kinetic data.
74:020-034
EFFECT OF SNOW COVER ON UPWARD MOVEMENT OF SOIL MOISTURE,
Peck, E.L.
National Oceanic and Atmospheric Administration, Silver Spring, Maryland.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 405-412, December, 1974. 2 fig, 15 ref.
28
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Descriptors: Soil water movement, Soil water, Snow, Snow cover, Snowfall,
Watershed management.
The information presented in this brief paper is neither sufficient nor conclu-
sive enough to demonstrate that soil moisture and temperature conditions under
the late season snow cover are a critical factor in determining the magnitude
of the snowmelt runoff. However, the evidence presented is sufficient to show
that: (1) Soil moisture under the snow cover in selected areas usually does
increase during the winter; and (2) the increase should be considered in
predicting the spring runoff. Further research on the magnitude of the effects
examined in this paper will probably indicate how conceptual watershed models
can be modified to account for the unusual moisture movement.
74:02G-035
FIELD TEST OF SOIL WATER FLUX METERS,
Dirksen, C.
U.S. Salinity Laboratory, Riverside, California.
Transactions of the ASAE, Vol. 17, No. 6, p 1038-1042, November-December, 1974.
4 fig, 1 tab, 5 ref.
Descriptors: *Soil water, *Soil water movement. Soil properties. Soil tests,
Tensiometers.
This field test represents an attempt to measure soil water fluxes directly in
essentially undisturbed soil. This was accomplished by excavating access
holes perpendicularly to the direction of flow with a specially designed
apparatus. Filter plates were pressed against undisturbed soil by a spring.
Fluxes were measured by adjusting the overall hydraulic head loss across the
meters, with a variable hydraulic resistance, to that in the soil nearby.
Two flux meters gave realistic results that were generally in good agreement
with each other. They reacted rapidly to different hydraulic resistance values
consistent with earlier laboratory tests. This is in sharp contrast with an
earlier attempt in which the access holes were dug by hand resulting in a
complete failure.
74:02G-036
SOME EFFECTS OF SUBIRRIGATION ON BENTGRASS DURING HEAT STRESS IN THE FIELD,
Krans, J.V. and Johnson, G.V.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Agronomy Journal, Vol. 66, No. 4, p 526-630, July-August, 1974. 5 fig, 3 tab,
10 ref.
(See 74:03F-157)
74:020-037
PROGRESS IN DRAINAGE,
Kuntze, H.
Niedersachsisches Landesamt fur Bodenforschung Ausseninstitut Bremen, F.R. of
Germany.
International Commission on Irrigation and Drainage, p 24-26, January 1974.
Descriptors: *Drainage, *Drainage engineering, Drainage practices, Drains,
Soil profiles, Automation.
When planning a drainage system, a careful survey and testing of soil profiles
and water table conditions should determine the most effective combination of
drain spacing, drain depth, kind of pipe and filter-wrap. Then a long useful
life can be guaranteed and even difficult soils become suitable for drainage.
In the future, the trenchless fully automatic drainage machine will provide
further reduction of cost. A variety of filter-wrapped plastic draintubes with
defined entrance holes have been adapted to the prevailing soil characteristics
of specific drainage areas. This wide range of different kinds of plastic tubes
in drainage has considerable advantages over the little variable tile drain.
29
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74-.02G-038
REVIEW OF WATERLOGGING AND DRAINAGE PROBLEMS AND THEIR SOLUTIONS IN INDIA,
Framji, K.K.
International Commission on Irrigation and Drainage 48, Nyaya Marg,
Chanakyapuri, New Delhi.
International Commission on Irrigation and Drainage, p 36-41, January, 1974.
13 ref.
Descriptors: *Drainage, *Drainage practices, Water table, Saturated soils,
Saturation, Groundwater, Groundwater movement.
The paper reviews the waterlogging that occurred almost everywhere in India on
the introduction of canal irrigation and which grew to menacing dimensions in
the absence of any in-built anti-waterlogging measures in the irrigation pro-
jects. The subsequent drainage provisions and their effects have been examined
in retrospect. The causes, effects and extents of waterlogging have been out-
lined and the important lessons learnt from experience and from the historical
studies on waterlogging and drainage have been touched upon with a cautionary
note against expectations from transference of knowledge and experience to other
problem areas. Research needs for obtaining scientifically precise anti-water-
logging measures and their design criteria have been indicated, but it is con-
cluded that with the modern methods of Systems Approach it should be possible
to evolve without waiting for research results, the optimized measures for
meeting the required conditions of integration of ground water and surface
water uses, and of irrigation and drainage networks for stable ground water
conditions at the required degree of relief and for ensuring permanent irri-
gated agriculture.
74:02G-039
FIELD TEST OF A MODIFIED NUMERICAL MODEL FOR WATER UPTAKE BY ROOT SYSTEMS,
Feddes, R.A., Bresler, E., and Neuman, S.P.
Institute of Soils and Water, Volcani Center, Bet Dagan, Israel, Department
of Soil Physics.
Water Resources Research, Vol. 10, No. 6, p 1199-1206, December, 1974. 6 fig,
2 tab, 35 ref.
Descriptors: *Model studies, *Root systems, Evapotranspiration, Root zone,
Water balance.
Data obtained from careful water balance studies on water uptake by the roots
of red cabbage are compared with results obtained from a modified numerical
model of Nimah and Hanks. In the modified model the air dry moisture content
at the soil surface may vary with time depending on meteorological conditions.
The maximum possible rate of evapotranspiration is calculated by considering
both meteorological conditions and crop properties. Data are quoted to suggest
that the coefficient of the root sink may sometimes vary exponentially with
depth.
74:02G-040
MORE OF AN APPROXIMATE SOLUTION FOR NONLINEAR DIFFUSION,
Brutsaert, W.
Cornell University, Ithaca, New York.
Water Resources Research, Vol. 10, No. 6, p 1251-1252, December, 1974.
11 ref.
Descriptors: *Diffusion, Mathematical studies, Soil water, Soil water
movement.
A method of solution developed earlier (1970) for a diffusivity, that is, a
power function of concentration, is shown to be more generally applicable.
One of the conditions of its applicability is the existence of a sharp
diffusing front. As an illustration the solution is worked out herein for
a diffusivity that has been useful in the analysis of soil water problems.
30
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74:02G-041
NITRATE CONCENTRATIONS IN DEEP SOIL CORES AS RELATED TO SOIL PROFILE CHARACTER-
ISTICS,
Lund, L.J., Adriano, D.C. and Pratt, P.P.
California University, Riverside, Department of Soil Science and Agricultural
Engineering.
Journal of Environmental Quality, Vol. 3, No. 1, p 78-82, January-March, 1974.
2 fig, 5 tab, 15 ref.
Descriptors: *Denitrification, *Nitrates, *Nitrogen, *Soil profiles, *Soil
horizons, Soil investigations.
Fifteen sites within a 30-ha study area were studied to determine the effect of
soil profile characteristics on nitrate concentrations below the root zone.
The N input, crop removal of N, and water management were similar for all sites
during the previous 6 years. The soils of the study area were primarily Alfi-
sois and Entisols of fine-loamy, coarse-loamy, sandy and sandy over loamy
families. Nitrate concentrations varied between sites and with depth. The
average nitrate concentrations below the root zone ranged from 4.9 to 15.3
micro-q when expressed on an oven-dry soil basis. Profile characteristics
were significantly correlated with the average nitrate concentrations below
the root zone. A regression equation relating average nitrate concentration in
the 1.8-8 m depth to control section characteristics explained 86% of the vari-
ability of the nitrate concentration and was highly significant. Hence, to
minimize ground-water pollution, soil profile characteristics should be
considered in selecting land for high N input whether by fertilization or
waste disposal.
74:02G-042
NITROGEN RELEASE ASSOCIATED WITH THE DECREASE IN SOIL ORGANIC MATTER IN NEWLY
CULTIVATED SOILS,
Reinhorn, T. and Avnimelech, Y.
Israel Institute of Technology, Haifa, Israel, Soils and Fertilizers Laboratory.
Journal of Environmental Quality, Vol. 3, No. 2, p 118-121, April-June, 1974.
2 fig, 2 tab, 18 ref.
Descriptors: *Nitrogen, *Organic matter, *Organic soils, Groundwater, Water
quality, Cultivation.
A marked decrease in soil organic matter occurs during the first years following
the cultivation of virgin soils. The purpose of this work is to study the
release of nitrogen, associated with this process. Technically, this was
achieved by a series of comparisons between cultivated plots and adjacent virgin
soils. It was found, that in the area under study, the decrease in soil organic
nitrogen was rather fast and a steady state was apparently achieved during the
first few years. The amount of nitrogen released during this process is up to
9 tons of N/ha. The amount of nitrogen released is linearily related to the
initial organic nitrogen content of the soil. In regions where large areas of
newly cultivated fields are found, this process may be a major factor respon-
sible for nitrate enrichment of the drainage water.
74:02G-043
FIELD STUDY OF SOLUTE MOVEMENT IN A HIGHLY AGGREGATED OXISOL WITH INTERMITTENT
FLOODING: II. PICLORAM,
Rao, P.S.C., Green, R.E., Balasubramanian, V., and Kanehiro, Y.
Hawaii University, Honolulu, Department of Agronomy and Soil Science.
Journal of Environmental Quality, Vol. 3, No. 3, p 197-201, July-September, 1974.
2 fig, 1 tab, 16 ref.
Descriptors: *Pesticides, *Herbicides, Soil chemistry, Water quality, Ground-
water, Irrigation, Soil profiles.
Most of the applied herbicide picloram was retained in the top 40-cm depth of
the Molokai soil with cumulative applications of 48 to 74 cm water following
application of the chemical to the soil surface. Although movement of the pic-
loram peak was retarded more than was anticipated from equilibrium adsorption
31
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measurements, a significant fraction of the applied herbicide moved ahead of the
peak deep into the profile (down to the 143-cm depth) after a single applica-
tion of 24-cm water. Rapid flow through macropore sequences combined with
temporary retention of picloram in aggregate micropores appear to be responsible
for the unusual pattern of movement. Published data for nitrate movement in
the same field plots of Molokai soil were compared with picloram movement data
to provide a measure of the relative mobility of these solutes. A comparison of
the results reported here with published field data of solute leaching in other
soils indicated a greater retardation of solute peak movement in Molokai soil
than in less aggregated soils.
74:020-044
NITRATE AND CHLORIDE ACCUMULATION AND DISTRIBUTION IN FERTILIZED TILE-DRAINED
SOILS,
Cast, R.G., Nelson, W.W., and MacGregor, J.M.
Minnesota University, St. Paul.
Journal of Environmental Quality, Vol. 3, No. 3, p 209-213, July-September,
1974. 5 fig, 3 tab, 9 ref.
Descriptors: *Nitrates, *Nitrogen, *Denitrification, Leaching, Soil water move-
ment, Fertilizers, Fertilization, Corn, Tile drainage, Drainage, Organic matter.
Results of long term continuous corn studies on tile drained Webster loam in
southwest Minnesota show that annual N applications up to 70% greater than N
removed in grain are required for maximum yields. The object of the reported
study was to establish the relative role of N incorporation into the soil organ-
ic matter and/or losses through denitrification, downward leaching, or tile
drainage in determining the fate of this fertilizer-N added above that removed
in corn grain. Nitrate and chloride accumulations and distributions were deter-
mined in a Webster loam and Waldorf silty clay loam profiles after long term
fertilization for continuous corn. Concentrations in the profiles were deter-
mined at 0.3 m depth intervals and at increasing distances from tile lines.
74:02G-045
THE EFFECT OF LARGE APPLICATION OF MANURE ON MOVEMENT OF NITRATE AND CARBON
IN AN IRRIGATED DESERT SOIL,
Meek, B.D., MacKenzie, A.J., Donovan, T.J., and Spencer, W.F.
Imperial Valley Conservation Research Center, Brawley, California.
Journal of Environmental Quality, Vol. 3, No. 3, p 253-258, July-September,
1974. 9 fig, 3 tab, 8 ref.
Descriptors: *Feedlots, Soil investigation, Irrigation, Nitrate, Carbon,
Manganese, Denitrification, Soil chemistry, Soil profile.
Feedlot manure was applied in the field at rates of 0, 45, 90, 180, and 360
metric tons/ha to a Holtville clay under irrigated conditions. Holtville
clay is a soil with restricted internal drainage. Ceramic cups were installed
at various depths in the soil profile to monitor the movement of manganese,
nitrate, and soluble organic carbon. The manure greatly increased the amount
of soluble organic carbon in the soil solution. An increase in the manure
application rate to 180 or 360 metric tons/ha increased the nitrate in the soil
solution at 20 and 40 cm, but there were only small differences at 80 and 140
cm. The lack of movement of nitrate to the 80-cm depth for the high rates of
manure application appeared to be due to denitrification, because high nitrate
levels were present in the surface soil and sufficient water was applied to
leach to this depth.
74:02G-046
COLUMN STUDIES OF SOIL CLOGGING IN A SLOWLY PERMEABLE SOIL AS A FUNCTION OF
EFFLUENT QUALITY,
Daniel, T.C. and Bouma, J.
Wisconsin University, Madison, Department of Soil Science.
Journal of Environmental Quality, Vol. 3, No. 4, p 321-326, October-December,
1974. 8 fig, 2 tab, 25 ref.
32
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Descriptors: *Septio tanks, *Soil disposal fields, *Clogging, *Effluents,
Chemical oxygen demand, Biochemical oxygen demand, Soil properties, Soil inves-
tigations, Soil structure, Soil water movement.
Clogging as a function of effluent quality was investigated in cores of the
very slowly permeable Almena silt loam soil which offers problems for conven-
tional on-site liquid waste disposal. Undisturbed 60 cm long cores were sub-
jected for approximately 120 days to constant ponding with simulated septic
tank effluent, extended aeration effluent and distilled water. Column influents
and effluents were monitored with respect to chemical oxygen demand (COD), bio-
chemical oxygen demand (BOD), and solid residue fractions. Column influents
differed markedly in COD and BOD content but column effluents had consistently
low contents indicating the high renovative capacity of the soil. In situ
tensiometric, redox, and flow rate measurements indicated development of the
most severe barriers to flow in columns ponded with low BOD aerated effluent,
followed closely by those ponded with high BOD septic tank effluent.
74:02G-047
COMPUTER MODELING OF NITROGEN TRANSFORMATIONS IN SOILS,
Mehran, M. and Tanji, K.K.
California University, Davis, Department of Water Science and Engineering,
Journal of Environmental Quality, Vol. 3, No. 4, p 391-395, October-December,
1974. 7 fig, 1 tab, 20 ref.
Descriptors: *Nitrification, *Dentrification, *Model studies, *Nitrogen,
Computer models, Soil profiles, Soil investigations.
A nitrogen-transformation model was formulated for simultaneous computation of
various N transformations: nitrification, denitrification, mineralization,
immobilization, ion exchange, and plant uptake. These processes were assumed
to obey first-order kinetics. Differential equations that describe the above
processes are solved simultaneously by using the 4th-order Runge-Kutta method
and the Adams-Bashforth-Moulton predictor-corrector equations. The computer
model was tested against data reported from several incubation studies. This
model could be linked to a transport model to predict the temporal and spatial
distribution of various N species in soil profiles.
74:02G-048
A SIMULATION MODEL FOR PREDICTION OF HERBICIDE PERSISTENCE,
Walker, A.
National Vegetable Research Station, Wellesbourne, Warwick, England.
Journal of Environmental Quality, Vol. 3, No. 4, P 396-401, October-December,
1974. 5 fig, 1 tab, 10 ref.
Descriptors: ^Simulation analysis, *Model studies, *Herbicides, Pollution,
Computer model, Soil investigation, Meteorological data-.
A simulation model for prediction of herbicide persistence in the field is
described. The model combines the effects of soil temperature and soil mois-
ture content on the rates of herbicide loss, determined experimentally under
controlled conditions, with the fluctuations in surface soil temperature and
moisture content in the field. The computer program includes methods of
simulating surface soil temperatures and moisture contents from standard meteor-
ological data. When data were used in the simulation model in conjunction with
the relevant meteorological information, the patterns of loss of napropamide
incorporated 2 to 3 cm in the field could be predicted. Napropamide was lost
rapidly when applied to the soil surface, and since the model only takes into
account losses through microbial or chemical metabolism, this could not be
simulated. Some of the limitations and the potential benefit, of the simula-
tion technique for prediction of pesticide persistence are discussed.
74:020-049
NITRATE AND CHLORIDE LEACHING IN A SWELLING CLAY SOIL,
Kissel, D.E., Ritchie, J.T., and Burnett, E.
Texas ASM University, Temple, Texas Agricultural Experiment Station.
33
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Journal of Environmental Quality, Vol. 3, No. 4, p 401-404, October-December.
1974. 4 fig, 3 tab, 9 ref.
Descriptors: *Nitrates, "Chloride, *Leaching, *Nutrient removal, Soil investi-
gations, Water quality, Lysimeter, Drainage water, Groundwater, Soil water
movement.
Leaching losses of applied NO(3)-N and Cl(-) from a swelling clay soil were
measured using an undisturbed field drainage lysimeter. Nitrate-N and Cl(-),
applied at 110 and 279 kg/ha, respectively, were detected in drainage water
collected at a depth of 125 cm after the first large rainstorm. Applied ferti-
lizer was leached when percolating rainwater carried the applied materials
through large connected pores, bypassing other soil water inside soil structural
units. Even though applied fertilizer began to be lost without the first
rainstorm, concentrations of NO(3)-N and Cl(-) were not high until large
amounts of water had drained below the root zone. Much more native soil nitrate
was leached than soil nitrate concentrations in unfertilized plants would have
indicated. The data indicate that leaching losses of nitrate from mineraliza-
tion may be greater than those of applied nitrate when accumulated drainage is
< 50 mm following fertilizer application.
74:02G-050
NITRATE OCCURRENCE IN SOME SOILS WITH AND WITHOUT NATRIC HORIZONS,
Gentzsch, E.P., Runge, E.G.A., and Peck, T.R.
Illinois University, Department of Agronomy.
Journal of Environmental Quality, Vol. 3, No. 1, p 89-94, January-March, 1974.
1 fig, 5 tab, 14 ref.
Descriptors: *Nitrates, *Nitrogen, *Soil properties, Soil investigations,
Fertilization, Fertilizers, Groundwater, Water quality.
The effect of animal activity and fertilizer practices on the nitrate content in
soils with and without natric horizons was investigated in a field study in
southern Illinois where excessive groundwater nitrate levels were reported.
Most of these soils are poorly drained. A comparison is provided by the poorly
and well-drained soils without natric horizons observed in central Illinois.
The results indicate that soils with natric horizons at shallow depths or
dark-colored poorly drained soils had low levels of nitrate in the profile;
all other soils showing increased nitrate levels in the entire profile or below
the root zone were related to the amount of fertilizer used or the amount of
animal activity. Animal operations resulted in larger amounts of nitrate in
similar soil profiles than did fertilizer applications. Increased nitrate
content of the groundwater, sampled in Washington County, similarly was related
to fertilizer practices and animal activity in all soils, except under soils
with natric horizons at shallow depths.
34
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Section VIII
WATER CYCLE
WATER IN PLANTS (Group 021)
74:021-001
EVALUATION OF A THERMOCOUPLE HYGROMETER FOR MEASURING LEAF WATER POTENTIAL IN
SITU,
Campbell, G.S. and Campbell, M.D.
Washington State University, Pullman, Department of Agronomy and Soils.
Agronomy Journal, Vol. 66, No. 1, p 24-27, January-February, 1974. 5 fig,
14 ref.
Descriptors: *Pressure measuring instruments, Pressure, Potato, Wheat,
Vapor pressure
Several methods for measuring leaf water potential in situ with thermocouple
paychrometers or hygrometers have recently become available. Disadvantages
of these methods include difficulty in construction or use, or excessive
modification of the leaf environment. Comparisons between in situ and other
measurements are generally lacking. We constructed an aluminum hygrometer
which is relatively easy to build and use and covers only about 1.'5 sq
cm of leaf area. This hygrometer was tested in the laboratory and the field
and readings were compared with those made with a pressure chamber for several
plant species. The leaf hygrometer worked well in both field and laboratory
situations. Comparisons between readings with the leaf hygrometer and a pres-
sure chamber gave regression lines with slopes of 1, but the average pressure
chamber reading was 0.4 to 1 bar lower than that obtained with the leaf
hygrometer. The leaf hygrometer appeared to respond to plant water potential
changes in less than 30 minutes. The equivalent error due to temperature
gradients within the chamber was found to be less than 0.4 bar. Measurement
precision with this technique appears to be about 1 bar or better.
74:021-002
PINKS ON A HIGH SALT DIET,
Belcher, C.R. and Gaffney, F.B.
Soil Conservation Service, Cape May Plant Materials Center, Cape May Court
House, New Jersey.
Soil Conservation, Vol. 40, No. 2, p. 11, September 1974.
Descriptors: Salinity, Salt, Saline water, Saline soil, Pine trees.
It's enough to send chills down the back of any gardener, but Soil Conservation
Service plant specialists in New Jersey are applying generous amounts of rock
salt around pine seedlings.
74:021-003
FIELD TEST OF A MODIFIED NUMERICAL MODEL FOR WATER UPTAKE BY ROOT SYSTEMS,
Feddes, R.A., Bresler, E. and Neuman, S.P.
Institute of Soils and Water, Volcani Center, Bet Dagan, Israel, Department
of Soil Physics.
Water Resources Research, Vol. 10, No. 6, p 1199-1206, December 1974. 6 fig,
2 tab, 35 ref.
(See 74:020-039)
74:021-004
DIFFERING SENSITIVITY OF CORN AND SOYBEAN PHOTOSYNTHESIS AND TRANSPIRATION
TO LEAD CONTAMINATION,
Bazzaz, F.A., Rolfe, G.L., and Windle, P.
Journal of Environmental Quality, Vol. 3, No. 2, p 156-158, April-June, 1974.
3 fig, 15 ref.
(See 74:056-044)
35
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Section VIII
WATER CYCLE
EROSION AND SEDIMENTATION (Group 02J)
74:02J-001
RESERVOIR SEDIMENTATION,
McHenry, J.R.
Agricultural Research Service, Oxford, Mississippi, Sedimentation Laboratory.
Water Resources Bulletin, Vol. 10, No. 2, p 329-337, April 1974. 1 fig, 2 tab,
18 ref.
Descriptors: *Reservoir silting, *Sedimentation, Erosion, Sediment control,
Sediment yield, Desilting, Reservoir design, Reservoir operation, Water manage-
ment (Applied), Sedimentation rates.
Reservoirs, as well as lakes and estuaries, are subject to sediment accumulation.
The rate at which sedimentation occurs is accelerated or diminished by man's
activities. Acceptable rates of sedimentation may be determined on the basis
of costs of sediment storage and removal. A review of reservoirs constructed
with sediment removal capabilities is given. The rates of reservoir sedi-
mentation in the United States are summarized based on reliable data obtained
from all sizes of reservoirs. Problems confronting the engineer concerning
reservoir construction and maintenance are discussed on the basis of these
data.
74:02J-002
SEDIMENT ROOTING IN IRRIGATION CANAL SYSTEMS,
Mahmood, K.
Colorado State University, Fort Collins, Department of Civil Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IRl, Paper 10401, p 49-67, March 1974. 8 fig, 3
tab, 12 ref, append.
Descriptors: *Sediment transport, *Irrigation water. Routing, Sedimentation,
Canals, Sediment control, Simulation analysis, Numerical analysis, Bed load.
The routing of bed material load through a branching irrigation canal system
may be calculated in such a way as to insure sediment discharge equilibrium.
All the sediment entering the system is disposed of with the water. The system
equilibrium can be more easily achieved if smaller sediment concentrations are
allocated to irrigation diversions from smaller channels. An approximate
numerical model predicts the bed material load from farm turnouts.
74:02J-003
CONCEPTS OP MATHEMATICAL MODELING OF SEDIMENT YIELD,
Bennett, J.P.
Geological Survey, Bay Saint Louis, Mississippi.
water Resources Research, Vol. 10, No. 3, p 485-492, June 1974. 1 fig, 34 ref.
Descriptors: *Sediment yield, *Mathematical models, Reviews, Equations,
*Erosion, Soil erosion, Sediment transport, Slopes.
A deterministic structure imitating a sediment yield model should mathematically
approximate the behavior of two distinct phases of the phenomenon, the upland
phase and the lowland channel phase. For upland erosion, research is most
36
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needed to explain the influence of meanders on bed material transport and to
develop a floodplain accounting component. In both phases, research is needed
to explain the effects of unsteadiness and flow nonuniformities on transport.
Sensitivity analysis studies of sediment yield models are needed to illustrate
how well the models can be calibrated and what output precision can be expected
from input data with known statistical characteristics. Present estimates
indicate that although a regression of annual sediment discharge on annual
water discharge might be expected to give a prediction within 20% of the ob-
served value, even a well-calibrated digital model might give an error greater
than 40% for a single storm on a small watershed.
74:02J-004
TOTAL SEDIMENT DISCHARGE SAMPLING OVER SILLS,
Hansen, E.A.
Forest Service (United States Department of Agriculture), Cadillac, Michigan.
North Central Forest Experiment Station.
Water Resources Research, Vol. 10, No. 5, p 989-994, October 1974. 5 fig, 2
tab, 8 ref.
Descriptors: *Sediment discharge, *Sampling, *Bed load, *Sands, Roughness
(Hydraulic), Turbulence, Streams, Sediment load, Bed load samplers, Measurement,
Discharge measurement, On-site data collections, Channels, Currents (Water).
Described were (1) the method of installation of wooden sills on the bed of
streams, (2) collection of bed load sediment data at the sills, (3) analysis
of the bed load sediment data, and (4) comparison of these results with bed
load sediment data collected at stream beds where sills were not installed.
It was indicated that wooden sills permit collection of bed load sediment
normally missed in the unsampled zone. The advantages associated with bed
load data collected at sills were; (1) sills provide a rigid unchanging con-
trol at which to sample, (2) they reduce the chance of sample bias from sedi-
ment stirred up by the wader, and (3) they permit control of the sampling
interval because the sample points can be marked directly on the sills. Anal-
ysis of the field data indicated that in all probability the 'sill samples'
provided better measurements of total sediment discharge than the traditional
stream samples. The nonuniformity of bed load discharge in the stream cross-
section complicated the problem of obtaining an unbiased sample of the total
sediment discharge.
74:02J-005
REGIONAL SEDIMENT YIELD ANALYSIS OF ALASKA STREAMS,
Guymon, G.L.
Alaska University, College. Institution of Water Resources. Journal of the
Hydraulics Division, American Society of Civil Engineers, Vol 100, No HY1,
Paper 10255, p 41-51, January 1974. 3 fig, 2 tab, 4 ref, append.
Descriptors: *Sediment yield, *Alaska, *Sediment load, Equations, *Regression
analysis. Sedimentation, Suspended load, Statistical methods, Sampling,
*Glaciohydrology.
Sparse suspended sediment data for Alaska were evaluated to verify regional
sediment yield relationships and to test alternative regression correlations
using readily obtained watershed parameters. Glacier-fed streams in the south-
central region of Alaska were emphasized, although one nonglacial stream in the
interior region of Alaska was included.for comparison. Plausible, simple
relationships can be developed for stream reaches well downstream from the
glacier which delivers a high fraction of the total suspended sediment load.
A great deal of uncertainty is associated with correlation attempts for short
stream reaches near the glacier delivery source.
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74:02J-006
EVALUATION IRRIGULAR SLOPES FOR SOIL LOSS PREDICTION,
Foster, G.R. and Wischmeier, W.H.
Purdue University, Lafayette, Indiana.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
p 305-309, March-April 1974. 3 fig, 8 ref.
Descriptors: *Soil erosion, Soil management, Soil conservation, Erosion, Slope
stability, Topography, Evaluation, Agriculture, Construction.
The effects of slope irregularities on soil erosion by water were analyzed on
the basis of recent progress in mathematical simulation of the basic erosion
processes. This report presents the analysis and extends it to routine field
application. A technique is proposed for evaluating the universal soil-loss
equation's topographic factor, LS, for irregular field or construction-site
slopes. The technique also provides a means of evaluating the effects of
differences in soil erodibility that may be associated with changes in slope
steepness. It does not, however, predict deposition that may occur on a slope.
Irregular slopes are not accurately evaluated by using average values for slope
steepness and soil erodibility in combination with overall length, and additional
very helpful detail can be readily obtained. The proposed technique has direct
application value both on farmland and on construction sites.
74:02J-007
EXPERIMENTAL STUDY OF RILL EROSION,
Mosley, M.P.
Colorado State University, Fort Collins, Geology Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No.5,
p 909-913 & 916, September-October 1974. 7 fig, 2 tab, 20 ref.
Descriptors: *Erosion rates, *Rill erosion. Surface runoff, Surface water,
Sediment yield, Sediment transport, Sheet erosion.
An experimintal study of soil erosion on unvegetated soil surfaces has shown
that a number of types of erosion may occur. These are, in approximate order
of importance, erosion by overland flow, microrilling, rainsplash, rill cutting,
and lateral planation by rills. Observation and simple statistical analysis
suggested that rilling was predominant; it was responsible for both detachment
of soil particles as the rill channels were incised, and for the transport of
particles detached by other processes, such as rainsplash. For rills which
had reached an "equilibrium" stage of development, sediment yielis were
positively related to surface slope and length, as previous research has shown
to be the case for sheet erosion in general. However, sediment yields were
also related to total rill channel length and drainage density? it appears that
rilling deserves more attention than it has hitherto received.
74:02J-008
SEDIMENT YIELD FROM SOUTHWEST IDAHO RANGELAND WATERSHEDS,
Johnson, C.W., Stephenson, G.R., Hanson, C.L., Engleman, R.L., and Englebert, C.D.
United States Department of Agriculture, Agricultural Research Service, Boise,
Idaho, Northwest Watershed Research Center.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 6 fig, 7 tab, 15 ref.
Descriptors: *Sediment yield, Idaho, Watersheds (Basins), Watershed management.
Runoff, Stream erosion.
Information collected shows that a small percentage of yearly runoff produces
most of the yearly sediment and that major floods occur during the winter.
38
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Contrary to what is normally observed, sediment concentrations and yearly
sediment yield increased with watershed size. Stream bank erosion seemed to be
the main source of sediment on the largest watersheds and "channel flushing"
caused high sediment concentrations.
74:02J-009
INFLUENCES OF MULCH RATE AND SLOPE STEEPNESS ON INTERRILL EROSION,
Lattanzi, A.R., Meyer, L.D., and Baumgardner, M.F.
Purdue University, West Lafayette, Indiana.
Soil Science Society of America Proceedings, Vol, 38, No. 6, p 946-950,
November-December, 1974. 4 fig, 4 tab, 14 ref.
Descriptors: *Erosion, *Erosion control, *Erosion rates, Infiltration, Runoff,
Soil conservation, Sediment yie'ld, Simulated rainfall, Mulching, Slope protec-
tion, Slope stabilization.
Soil and water losses from plots representing field areas between rills were
studied for four rates of straw mulch at four slope steepnesses. Three simu-
lated rainstorms totaling 2 hours at 6.4 cm/hour were applied to a 61- by 61-cm
test area of Russell silt loam soil. Interrill erosion was reduced about 40%
by mulch applied at a rate of only 0.5 metric tons/ha and about 80% by 2 tons/ha,
as compared with no mulch. Erosion was negligible at the 8 tons/ha rate.
Soil losses from the interrill areas at 20% slope were only about double those
measured at 2% slope, whereas widely used erosion equations show that total
field erosion would increase about 20-fold over this range of steepnesses.
Water loss by runoff was independent of slope steepness, but it was slightly
reduced by mulch at a rate of 2 tons/ha and was greatly reduced by the 8 tons/ha
rate. After 40 minutes of rainfall, sealing of the soil surface by raindrop
impact had reduced infiltration rates for treatments with 0 to 2 tons/ha of
mulch to only 20% of those with 8 tons/ha.
74:02J-010
SEDIMENT IN IRRIGATION AND DRAINAGE WATERS AND SEDIMENT INPUTS AND OUTPUTS FOR
TWO LARGE TRACTS IN SOUTHERN IDAHO,
Brown, M.J., Carter, D.L., Bondurant, J.A.
Snake River Conservation Research Center, Kimberly, Idaho.
Journal of Environmental Quality, Vol. 3, No. 4, p 347-351, October-December,
1974. 1 fig, 3 tab, 10 ref.
Descriptors: *Sediment discharge, *Sediment control, *Sediment yield, *Sedi-
mentation, Runoff, Return flow, Water quality, Water quality control.
Sediment inputs from Snake River irrigation water and sediment losses back to
the river were measured for two large irrigated tracts in southern Idaho.
There was a net sediment accumulation of 0.69 metric tons/ha onto the 65,000
ha Northside tract but a net sediment loss of 0.46 metric tons/ha from the
82,000 ha Twin Falls tract. Differences in sediment losses from the two
tracts result from the difference in sedimentation in the drain-ways of
the two projects. Sediment deposited in drains on the Northside tract amounted
to 4.5 metric tons/ha compared to 0.95 metric tons/ha for the Twin Falls
tract. Erosion loss from farms could be reduced within each tract by more care-
ful use of water and construction of on-farm sediment retention ponds. This
would also reduce the amount of sediment returned to the river and lower costs
of mechanically removing sediment from drains and canals. Construction of
sediment retention ponds along main drains and reducing the amount of surface
runoff returning to the river would also reduce the amount of sediment returning.
39
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Section IX
WATER CYCLE
CHEMICAL PROCESSES (Group 02K)
74:02K-001
THE INFLUENCE OP GEOLOGICAL MEMBRANES ON THE GEOCHEMISTRY OF SUBSURFACE WATERS
FROM MIOCENE SEDIMENTS AT KETTLEMAN NORTH DOME IN CALIFORNIA,
Kharaka, Y.K. and Berry, F.A.F.
California University, Berkeley, Department of Geology and Geophysics.
Water Resources Research, Vol. 10, No. 2, p 313-327, April 1974. 11 fig, 3
tab, 40 ref.
Descriptors: *Water chemistry, *Oil fields, *Membrane processes, Geochemistry,
California, Water temperature, Sodium, Ammonia, Magnesium, Calcium, Strontium,
Chlorides, Sulfates, Iodine, Bromine, Silica, Ion exchange, clays, Zeolites,
Shales.
In the Kettleman North Dome oilfield in California, the waters from the Temblor
formation (Miocene) are principally meteoric in origin, related to recharge
areas located to the west. Their chemistry relative to meteoric water is at-
tributed to hyperfiltration through geological membranes as well as to water-
rock interactions. The chemistry of the waters in each subzone of the Temblor
formation is characteristic of that subzone and shows membrane effluent char-
acteristics to a given subzone with respect to the one stratigraphically be-
low it. The chemical relations are attributed to increased efficiency of
shale membranes with increased depth of burial. Membrane behavior of shales
controls completely or in part the distribution of the following ratios:
Li/Na, Rb/Na, KH3/Na, Mg/Ca, Sr/Ca, Ca/Na, alkalinity/Cl, SO4/C1, I/Br, and
B/Cl. Some of these ratios are modified by temperature-controlled water-
rock interactions. The K/Na ratios and the SiO2 and Ba concentrations are
completely dependent on water-rock interactions.
40
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Section X
WATER SUPPLY AUGMENTATION AND CONSERVATION
WATER YIELD IMPROVEMENT (Group 03B)
74:036-001
SEEPAGE LOSSES FROM IRRIGATION CANALS,
Horcher, F. and Szigyarto, Z.
International Commission on Irrigation and Drainage, p 63-70, January 1974.
2 fig, 2 tab, 16 ref.
Descriptors: *Seepage, ^Irrigation canals, Irrigation effects, Hater loss,
Water conveyance, Water consumption.
Since the setting up of the Trans-Tisza District Water Authority in 1963, syste-
matic studies have been made by the Research Institute for Water Resources
Development in the irrigation system of the Deleti (Eastern) irrigation main
canal or precisely speaking, in the irrigation section K.IV of this system to
develop both the design principles and operation regulations of irrigation canal
systems. In this paper the results of the previous experimental series are
summarized, and studies carried out between 1967 and 1971 on the determination
of seepage losses in the main canal of the irrigation section K.IV are
described.
41
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Section XI
WATER SUPPLY AUGMENTATION AND CONSERVATION
USE OF WATER OF IMPAIRED QUALITY (Group 03C)
74:030001
EFFECTS OF COLORADO RIVER WATER QUALITY AND SUPPLY ON IRRIGATED AGRICULTURE,
Moore, C.V., Snyder, H.H. and Sun, P.
Economic Research Service, Davis, California.
Water Resources Research, Vol. 10, No. 2, p 137-144, April 1974. 7 fig, 2 tab,
4 equ, 8 ref.
Descriptors: *Irrigation water, *Water supply, *Saline water, *Water quality,
Agriculture, Estimating, Linear programming, Regional analysis, Water demand,
Irrigated land, Optimization, Colorado River, Farms, Size, Soils, Prices, Water
rates, Mathematical models, Systems analysis, *California.
Considered are salination effects upon irrigation water supplies in the Im-
perial Valley of California. A production function relating irrigated crop
yield to the quality and supply of irrigation water is developed. The ob-
jective function is to maximize the return to land and water. Described is a
linear programming, farm model constructed to estimate the probable effects
of various levels of supply and quality. A regional programming model, an
aggregation of three different size individual farms, reflects the distribution
of soils and the cost structure representative of farm size. Given the produc-
tion function, cropping pattern and irrigation management can be optimized
using the linear programming models. Use of the regional model for estimating
the demand schedule for irrigation water is discussed. Results show that the
adverse effects of saline irrigation water can be offset by applying additional
water over and above that required for plant transpiration. A degradation of
the water supply in the Colorado River at Imperial Dam from the existing level
of electroconductivity to the projected level for the year 2000 would cause a
decline in the return to land and water of about 14%. Because of the relatively
elastic demand for irrigation water at the current price, any attempt to ration
water through a market price mechanism would have no effect, unless water rates
were about double their current levels.
74:03C-002
AUSTRALIAN VINEYARD USES SEWAGE EFFLUENT WITH TRICKLE IRRIGATION,
Read, A.L., Pietsch, M.F. and Matheson, W.E.
Kinnaird Hill deRohan and Young, Ltd. Norwood, South Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 382-387,
July 1974.
Descriptors: *Effluents, *Sewage, *Sewage disposal, *Sewage effluents, *Vine
crops, Irrigation, Irrigation systems, Irrigation practices, Agriculture,
Clogging.
The Angle Vale Vineyard is located 32 kilometres north of Adelaide, South
Australia. Supplementary irrigation is necessary for the growth of vines in
the area. In 1970, Government legislation precluded the future use of water
in the area, and a decision was made to use sewage effluent from Adelaide
which was the only supplementary irrigation available. The 40 hectare vineyard
had trickle irrigation installed and has since been enlarged to 180 hectares.
The effluent has a T.D.S. varying from 1,300 to 1,800 mg/1 and a varying but
high algal content. The paper describes the problems of filtration and growths
within the pipelines and how these problems were overcome. Monitoring of soil
conditions has been necessary to study the changes in soil salinity. Maximum
salinities have occurred at the perimeter of the wetted zone, approximately 50
cms from the vine rows. Total soluble salts have increased from 0.035% in the
centre of the vine rows to 0.086-0.109% at the perimeter of the wetted zones.
Analyses of the vine leaves and wine made from the first vintage are also repor-
T16Q •
42
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74:030-003
SALT TOLERANCE OF MEXICAN WHEAT: II. RELATION TO VARIABLE SODIUM CHLORIDE
AND LENGTH OF GROWING SEASON,
Bernal, C.T., Bingham, F.T., and Oertli, J.
California University, Riverside, Department of Soil Science and Agricultural
Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 777-779,
September-October, 1974. 7 fig, 2 tab, 15 ref.
(See 74:03F-133)
74:03C-004
SURFACE PLUGGING DURING BASIN RECHARGE OF TURBID WATER,
Jones, O.R., Goss, D.W., and Schneider, A.D.
United States Department of Agriculture, Southwestern Great Plains Research
Center, Bushland, Texas.
Transactions of the ASAE, Vol. 17, No. 6, p 1011-1014 & 1019, November-December
1974. 7 fig, 2 tab, 9 ref.
(See 74:03F-149)
74:03C-005
GROWTH RESPONSE OF CROPS TO DEPTH AND SALINITY OF GROUNDWATER AND SOIL SUBMER-
GENCE. I. WHEAT (TRITICUM AESTIVUM L.)
Chaudhary, T.N., Bhatnagar, V.K. and Prihar, S.S.
Punjab Agricultural University, Ludhiana, India, Department of Soils.
Agronomy Journal, Vol. 66, No. 1, p 32-35, January-February, 1974. 3 fig,
4 tab, 10 ref.
Descriptors: Salinity, Saline soil, Saline water, Crop response, Crop pro-
duction, Groundwater, Lysimeters.
Information on crop response to depth and salinity of groundwater and soil
submergence is important for planning drainage and optimizing crop production.
Response of a semidwarf wheat to four depths (60, 90, 120, and 150 cm) and
three salinities (EC 0.5, 2.9, and 5.2 mmho/cm) of groundwater was studied
in lysimeters filled with silt loam soil during 1970-71 and 1971-72. The
plants were irrigated with water of EC 0.5 mmho/cm when the lysimeters with
a 150-cm water table depth indicated a tension of 0.5 bar at a 75-cm depth.
Groundwater of EC 0.5 mmho/cm at 60 and 90-cm depths gave highest yields.
Comparable increase in the salinity of groundwater caused greater reduction in
yield with shallow water tables than with deep water tables. It is indicated
that critical depth of groundwater, for optimum crop production, would vary in
relation to its salinity.
43
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Section XII
WATER SUPPLY AUGMENTATION AND CONSERVATION
CONSERVATION IN AGRICULTURE (Group 03F)
74:03F-001
FUNCTIONS TO PREDICT OPTIMAL IRRIGATION PROGRAMS,
Stewart, J.I., Hagan, R.M. and Pruitt, W.O.
California University, Davis, Department of Water Science and Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR2, Paper No. 10626, p 179-199, June 1974. 5 fig,
5 tab, 36 ref.
Descriptors: *Irrigation programs, *Irrigation efficiency, *Optimum devesed-
ment plans, Evapotranspiration, *Droughts, Scheduling, Soil water, Vegetation,
Seasonal, Corn(Field), Research, Measurement, Systems analysis.
Maximum water-use efficiency often occurs at irrigation levels still lower than
the maximum profit point. A methodology is presented for prediction of opti-
mal irrigation programs at any given level of irrigation water supply. The
prediction is based on analysis of: (1) Davis, California research findings
concerning growth characteristics of the crop which influence maximum yield,
evapotranspiration (ET) requirement, soil water uptake, and response to ET
deficits; and (2) measurements of climate, soil, and irrigation system per-
formance which influence the requirement for ET to be supplied from irrigation,
and the percentage of irrigation water evapotranspired. An optimal program
maximizes profit or water-use efficiency. Programming dates and depths of
irrigations are based on comparison of the estimated sequence of maximum ET
rates throughout the season with the sequence of actual ET rates expected if
no irrigation is given. The difference constitutes an expected sequence of ET
deficits which carefully programmed irrigations may alleviate fully or in part.
Time relationships of corn leaf canopy and root system development researched
at Davis are combined with irrigation planning site measurements of climate,
soil, and soil water content to estimate the sequence of ET deficits. Measure-
ment of actual irrigation operational efficiency completes the needed infor-
mation.
74:03F-002
TOWARD THE STRUCTURE OF A PRODUCTION FUNCTION FOR WHEAT YIELDS WITH DATED IN-
PUTS OP IRRIGATION WATER,
Minhas, B.S., Parikh, K.S. and Srinivasan, T.N.
Indian Statistical Institute, New Delhi, Planning Unit.
Water Resources Research, Vol. 10, No. 3, p 383-393, June 1974. 6 fig, 4 tab,
16 equ, 27 ref.
Descriptors: *Irrigation water, *Irrigation efficiency, Water utilization,
"Crop response, *Soil moisture, Analytical techniques, *Wheat, *Alfalfa, Esti-
mating, Yield equations, Ohio, Optimization, Time, Methodology, Evapotranspira-
tion, Water quantity, Plant growth, Water allocation(Policy), Systems analysis.
To date, the interdependence between the rate of water used by plants and the
available stocks of moisture in the soil, the temporal interdependence between
water use at different time points, and the consequences of these interdepend-
encies for the relationship between time profiles (as well as quantities) of
water used by crop plants and yields generally have not been analyzed in a
unified framework. Presented is one such framework for the analysis of opti-
mal use of irrigation water. The mathematical form of a water use function,
44
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estimated from experimental data, has been used to compute the time profiles
of actual water use for wheat in Delhi (India) and alfalfa in Ohio. The esti-
mated time profiles of consumptive use have been used to determine the relation-
ship between wheat yields and dated inputs of water in Delhi.
74:03F-003
DATING TERMINATION OF COTTCN IRRIGATION FROM SOIL WATER-RETENTION CHARACTER-
ISTICS,
Grimes, D.W. and Dickens, W.L.
California University, Davis, Department of Water Science and Engineering.
Agronomy Journal, Vol. 66, No. 3, p 403-404. 1974 Illus.
In the semiarid San Joaquin Valley of California (USA), about 90% of the evapo-
transpiration needs for nonstressed cotton (Gossypium hirsutum L.) are met by
irrigation. Soil water-retention characteristics determine the frequency with
which irrigations must be made to replenish depleted soil water during the
growing season, studies were conducted in the San Joaquin Valley, on 2 soils
that have a broad difference in water retention ability, to determine the best
irrigation termination date for cotton. A multiple-regression model that in-
cluded time of irrigation termination and water retention capacity of soil
as independent variables was used to describe the influence of these variables
on cotton production potential (R2=0.71). Prepared from the function was a
graphic relation illustrating an irrigation termination time that allows a 98%
relative yield on the basis of the amount of available water the soil can re-
tain. An optimum irrigation termination time was 28 days later for the low
water-retaining soil of the study than for the high water-retaining soil.
Correct timing of a final irrigation saved water and hastened the opening of
mature bolls without harm to lint yield or quality.
74:03F-004
COMPARISON OF DRAINAGE METHODS IN A HEAVY-TEXTURED SOIL,
Schwab, G.O., Fausey, N.R. and Michener, D.W.
Ohio Agricultural Research and Development Center, Wooster.
Paper No. 72-727 presented at Winter Meeting of the American Society of Agri-
cultural Engineers, December 11-15, 1972, Chicago, Illinois. 5 p, 1 tab, 6 ref.
Descriptors: *Drainage, Surface drainage, Subsurface drainage, Tile drainage,
Crop response, Soil water, Drainage engineering, Soil water movement.
Corn, oat, and soybean yields from surface drained, tile drained, and a combi-
nation of tiled and surface drained plots in northern Ohio were obtained over
a 10-year period. Both conventional tillage and no tillage practices were in-
cluded. Rainfall plus irrigation and drainage flow effects on yields were
studied by linear regression techniques.
74:03F-005
INFILTRATION AND ROOT EXTRACTION FROM SUBSURFACE IRRIGATION LATERALS,
Gilley, J.R. and Allred, E.R.
Minnesota University, St. Paul, Department of Agricultural Engineering.
Paper No. 72-743 presented at Winter Meeting of the American Society of Agri-
cultural Engineers, December 11-15, 1972, Chicago, Illinois. 27 p, 11 fig, 4
tab, 29 ref*
Descriptors: Irrigation, *Subsurface irrigation, Irrigation practices, Soil
moisture, Soil water movement, Soil physics, ""Infiltration, Model studies.
An analytical solution to the soil moisture flow equation was used to simulate
flow in partially saturated soils during steady infiltration from buried line
45
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sources. A series of plane sinks was used to model water consumption by plants.
The resulting model was used to determine optimum lateral placement to obtain
desired crop extraction patterns.
74.-03P-006
PROCEEDINGS OF THE SECOND INTERNATIONAL DRIP IRRIGATION CONGRESS,
Second International Drip Irrigation Congress,
California University and United States Department of Agriculture, Agriculture
Research Service.
Second International Drip Irrigation Congress, July 7-14, 1974, San Diego,
California.
Descriptors: Crop response, Design, Design criteria, Design flow, Economics,
Evaporation pans, Fertilization, Furrow irrigation, Hydraulic properties,
Infiltration, Irrigation effects, Irrigation efficiency, Irrigation practices,
Irrigation water, Mathematical models, Orifice flow, Orchards, Return flow,
Root development, Salinity, Soil water movement, Subsurface irrigation.
Research related to trickle irrigation (drip irrigation) is being conducted
throughout the United States and in many other countries of the world. The 101
papers presented discuss topics such as design methods, hydraulics, crop
response, salinity, water filtration, fertilization, irrigation scheduling,
emitter design, emitter clogging, wetting patterns, and much more as related
to this relatively new irrigation method.
74:03F-007
PERFORMANCE OF PLANTS WITH DRIP IRRIGATION,
Aljibury, F.K., Gerdts, M. , Lange, A., Huntamer, J. and Leavitt, G.
San Joaquin Valley Agricultural Research and Extension Center, Parlier,
California.
Proceedings of the Second International Drip Irrigation Congress, pp. 497-502,
July 1974. 2 fig, 3 tab, 3 ref.
Descriptors: *0ranges, *Water utilization, *Crop response, Penetration,
Furrow irrigation, Crop production, Irrigation practices, Irrigation, Agri-
culture.
Experiments were established to study the effect of drip irrigation on water
use efficiency and production in oranges and to study the effect of drip and
furrow irrigation on water penetration and performance of plums. Orange pro-
duction records show higher production with drip irrigation which is attributed
to improved water penetration. Plum production records show no significant
difference in production or fruit quality, but irrigation efficiency was
improved.
74:03F-008
THE RELATION BETWEEN DRIP IRRIGATION, PHYTOPHTHORA ROOT ROT OF AVOCADO, AND
FUNGICIDES,
Zentmyer, G.A., Guillament, F.B. and Johnson, E.L.V.
California University, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 512-514,
July 1974.
Descriptors: *Diseases, *Disease resistance, *Fungicides, Irrigation practices,
Irrigation systems, Irrigation, Agriculture.
Studies have been initiated to determine the effect of drip irrigation on
development, spread and control of Phytophthora root rot of avocado caused by
Phytophthora cinnamomi. In one test in naturally infested soil, development
of Phytophthora root rot of avocado seedlings was considerably slower under
drip than under sprinkler irrigation. There were also indications of less
rapid spread of the fungus from infested into noninfested soil under the drip,
as compared with the sprinkler regime. At the end of the first year of the
experiment, 6 of 12 seedlings were still healthy in soil infested with P.
cinnamomi when irrigated with a drip system, compared with 2 healthy seedlings
of 12 irrigated with spitters. A number of soil fungicides have been tested
46
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in the greenhouse for possible use in drip systems, by applying frequent appli-
cations (every other day or every fourth day) to avocado seedlings growing in
soil infested with Phytophthora cinnamorai. The best control of the disease
has been obtained with ethazol (5-ethoxy-3-trichloremethyl-l, 2, 4-thiadiazole)
chemicals for incorporation in drip systems is still in the early stages. One
field plot has been established with Terrazole applied in a drip system to
10-year old avocado trees infected with Phytophthora root rot, and also to young
trees replanted in infested soil.
74:03F-009
WATER USE WITH DRIP IRRIGATION,
Aljibury, F.K., Marsh, A.W. and Huntamer, J.
San Joaquin Valley, Agricultural Research and Extension Center, Parlier,
California.
Proceedings of the Second International Drip Irrigation Congress, pp. 341-345,
July 1974.
Descriptors: *Evaporation pans, *Water requirements, Irrigation practices,
Irrigation water, Irrigation system, Irrigation design, Frequency.
In the absence of proper equations to calculate water requirements with drip
irrigation, irrigation consultants and dealers in California have used the
same water use data developed for conventional irrigation systems. Since one
of the primary advantages of drip irrigation is water savings, development of
water budget to fit drip irrigation became necessary. To accomplish this
objective, several drip irrigation studies were initiated in the San Joaquin
Valley of California. These studies were conducted on farms where citrus,
avocados, plums, olives, and grapes were grown. Applied water was measured
using flow meters while the frequency and amount of water application was deter-
mined with tensiometers which were set to switch the water on at 30 centibars.
Water evaporation from Class A pans established in large alfalfa fields was
recorded regularly. A table is presented showing suggested drip water applica-
tion as a function of Class A pan evaporation and percent plant coverage.
74:03F-010
DRIP IRRIGATION ON CITRUS,
Bester, D.H., Letter, D.C. and Veldman, G.H.
Zebediela Estates, Republic of South Africa.
Proceedings of the Second International Drip Irrigation Congress, pp. 58-64,
July 1974. 2 fig, 1 tab.
Descriptors: *Evaporation pans, Irrigation, Agriculture, Sprinkler irrigation,
Wetting, Fertilization, Filtration, Orchards, Citrus fruits.
A comparative study was conducted on citrus to establish the comparative
efficiency of drip irrigation, dragline sprinkler irrigation, and a hose system
discharging water directly into irrigation basins in South Africa. The follow-
ing aspects of drip irrigation were investigated: 1) Soil moisture determina-
tions and wetting patterns, 2) the possibility of using an evaporation pan to
determine irrigation requirements, 3) the effect of different numbers and spac-
ing of drippers per tree, 4) the effect of different dripper discharge rates,
5) practicability of using microtubes as drippers, 6) the possibility of
applying fertilizers through a drip irrigation network, and 7) factors affecting
the distribution efficiency of a drip irrigation system.
74:03F-011
CHANGE IN ROOT DISTRIBUTION OF MATURE PEAR TREES IN RESPONSE TO TRICKLE IRRI-
GATION,
Black, J.D.F. and Mitchell, P.O.
Victorian Department of Agriculture, Ferntree Gul-ly, Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 437-438,
July 1974.
Work reported was designed to obtain an idea of the rate of adaption of the
root distribution of pear trees grown under uniform sprinkler irrigation for 18
years and then converted to trickle irrigation for two years with one emitter
47
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per tree. Flow rate per emitter was 8 A per hour per tree. After two seasons
the entire root system of 4 trees was exposed and examined for changes in
response to the continuously moist but restricted wetted soil volume in the
root zone. The intensity of new root growth was markedly higher inside the
wetted soil volume.
74:03F-012
WATER UPTAKE BY AN APPLE TREE WITH VARIOUS PROPORTIONS OF THE ROOT SYSTEM
SUPPLIED WITH WATER,
Black, J.D.F. and West, D.W.
Victorian Department of Agriculture, Ferntree Gully, Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 432-433,
July 1974. 1 fig, 1 tab.
Descriptors: *Apple, *Root development, Irrigation, Agriculture.
Water uptake by young apple trees with 1/4, 1/2, and 3/4 of their root systems
supplied with water was related to the uptake with the total system supplied
with water in a split root pot trial. The respective percentages of water up-
take compared with the totally watered system were 74, 88, and 94 percent.
74:03F-013
MONITORING SOIL SALINITY AND LEAF NUTRIENT LEVELS IN A YOUNG AVOCADO ORCHARD
UNDER DRIP IRRIGATION, v.n««u
Branson, R.L., Gustafson, C.D., Marsh, A.W., Davis, S. and Strohman, R.A.
California University, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 364-367
July 1974. 2 tab, 5 ref.
Descriptors: *Salinity, *Monitoring, *0rchards, *Leaching, *Nutrients,
Irrigation, Agriculture.
Salinity control is an important part of the management program for avocado pro-
duction because of this crop's low tolerance to salts. Soil salinity in the
root zone of a newly planted avocado orchard was monitored for four years. The
orchard, located in a semi-arid region of southern California, is irrigated
with a moderately saline water from the Colorado River. Soil salinity rose
to marginal levels during each irrigation season under both irrigation methods.
Winter rainfall, however, leached accumulated salts from the soil each year.
Distribution of the rainfall, as well as total amount, was an important
factor with regard to adequacy of leaching. Leaf samples were analyzed annually
to obtain information on the uptake of chloride, an ion toxic to avocado at
relatively low levels. Leaf analysis data are also being used to evaluate the
fertilization program.
74.-03F-014
TRICKLE IRRIGATION MANAGEMENT FOR COTTON AND CABBAGE,
Bucks, D.A., Erie, L.J. and French, O.F.
United States Water Conservation Laboratory, Phoenix, Arizona.
Proceedings of the Second International Drip Irrigation Congress, pp. 351-356
July 1974. 5 fig, 4 ref.
Descriptors: *Cotton, *Frequency, Consumptive use, *Water utilization,
Agriculture, Irrigation, Furrow irrigation, Comparative productivity, Crop
response.
Cotton and cabbage studies were initiated to evaluate the effects on crop pro-
duction of specified quantities and frequencies of water applications using
trickle irrigation. Different quantities of irrigation water were applied at
frequencies of 3, 6, and 12 days. Both studies were conducted on small plots
of fine-textured, clay-loam soil, using a moderately saline water. Results
of these studies indicate the following: (1) the amount of soil moisture needed
by the cotton and cabbage plants for high production was approximately the same
as the presently-accepted consumptive use; (2) increasing frequency of trickle
to 3 days did not increase yields on this soil; and (3) trickle irrigation can
decrease irrigation water requirements under conditions where furrow-irrigation
would not attain a high overall irrigation efficiency.
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74:03F-015
TRICKLE IRRIGATION MANAGEMENT FOR GRAPES,
Bucks, D.A., Erie, L.J., Nakavama, F.S. and French, O.F.
United States Water Conservation Laboratory, Phoenix, Arizona.
Proceedings of the Second International Drip Irrigation Congress, pp. 503-507,
July 1974. 3 fig, 1 tab, 3 ref.
Descriptors: *Crop response, Agriculture, Irrigation, Consumptive use. Furrow
irrigation, Frequency, Water utilization, Irrigation design, Irrigation prac-
tices, Water requirements.
A three-year field investigation is being conducted to determine irrigation
management and design requirements for grape production. Trickle irrigation
treatments include three irrigation quantities, based on ratios of a consump-
tive-use estimate; three irrigation frequencies—daily, 3-day and 6-day;
and a variation of one or two trickle irrigation emitters per vine. Furrow
irrigation treatments include the same three seasonal quantities used for the
trickle irrigation applied in two or three furrows per vine; however, the irri-
gation frequency is varied, based on the consumptive use. First-year results
were as follows: there was a 13 percent increase in yield for trickle irriga-
tion with two emitters per vine over furrow irrigation; a 9 percent greater
yield for two emitters over one emitter per vine; a 6 percent increase in berry
size for trickle-irrigated fruit over furrow-irrigated; little difference
in sugar content between irrigation treatments; and little difference in yield
between trickle irrigation frequencies.
74:03F-016
RESPONSE OF MATURE CITRUS TRESS ON DEEP SANDY SOIL TO DRIP IRRIGATION,
Cole, P.J. and Till, M.R.
South Australian Department of Agriculture, Adelaide, Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 521-526,
July 1974. 1 fig, 4 tab, 1 ref.
Descriptors: *Oranges, *Crop response, Agriculture, Irrigation, Management
orchards, Salinity, Irrigation design. Irrigation practices, Irrigation systems.
A demonstration trial on mature vallencia oranges was established to provide
guidelines for future drip irrigation management in Australia. The trees are
on a deep sandy soil and were established and previously maintained by sprinkler
irrigation. There may be up to 450 mg/1 total dissolved salts in the irrigation
water. Two designs of drip irrigation have been used - one with a row of
drippers along the base of the trees only, and the other with a line along
both the base and in midrow. There are twice the number of drippers in this
latter system, each of half the flow rate of the former. A difference in per-
formance of trees are yielding less than sprinkler irrigated trees, with double
line drip irrigation better than single line drip irrigation.
74:03F-017
INFLUENCE OF DIFFERENT AMOUNTS OF IRRIGATION—WATER, IRRIGATION—INTERVALS AND
FERTILIZERS ON THE YIELD AND QUANTITY OF DRIP-IRRIGATED MUSK-AND WATERMELONS,
Dan, C.
Ministry of Agriculture, Beisan, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 425-430,
July 1974. 8 tab.
Descriptors: *Melons, *Fertilization, *Crop response, Agriculture, Irrigation.
Trials were initiated to determine irrigation and fertilization practices to
promote high muskmelon and watermelon yields of satisfactory quality. Yields
were not affected by different amounts of irrigation water or by different
irrigation schedules.
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74:03F-018
THE IRRIGATION OF OLIVES BY DRIP AND OTHER IRRIGATION METHODS,
Dan, C.
Ministry of Agriculture, Beisan, Israel
Proceedings of the Second International Drip Irrigation Congress, pp. 491-496,
July 1974. 4 tab.
Descriptors: *Crop response, Agriculture, Irrigation.
Drip irrigated young trees gave higher and earlier yields before attaining
full maturity, than trees irrigated by any other method. The number of
emitters per tree was not found to be critical in the range of 4 to 8 emitters
per tree. The yields of mature trees which were converted to trickle irrigation
were generally somewhat higher than before.
74:03F-019
DRIP IRRIGATION: SURFACE AND SUBSURFACE COMPARED WITH SPRINKLER AND FURROW,
Davis, S. and Pugh, W.J.
United States Department of Agriculture, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 109-114,
July 1974. 3 fig, 2 tab, 2 ref.
Descriptors: *Furrow irrigation, *Sprinkler irrigation, *Subsurface irrigation,
Melons, Agriculture, Irrigation.
This paper reports on four studies that compared crop response to various com-
binations of drip, subsurface, furrow and sprinkler irrigation. Study concludes
that, 1) when the amount of water applied is near the consumptive use require-
ment, subsurface irrigation has greater production and better water use
efficiency, 2) less water is needed for drip and subsurface irrigation than for
furrow or sprinkler irrigation, because less water is lost to direct evapora-
tion and deep percolation, and 3) the applicators used applied water equally
well to the surface or subsurface soil, except where deposits from evaporation
occurred.
74:03F-020
DRIPPER FLOW CONSISTENCY,
Davis, S. and Pugh, W.J.
United States Department of Agriculture, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 281-283,
July 1974. 6 fig.
Descriptors: *Flow characteristics, *Flow rates, *Application equipment
Equipment, Agriculture, Irrigation.
Several different emitters have been checked for flow consistency volumetrically,
both in time for the same emitter and for several emitters along the applicator
line. Results of two years' study show many of the applicators vary more than
+5% from the average. With the exception of a few drippers that were par-
tially clogged or improperly manufactured, most of the drippers provided con-
sistent water distribution both along the line and with time.
74:03F-021
SOIL SALINITY DISTRIBUTION IN DRIP AND SUBSURFACE IRRIGATED SUMMER SQUASH,
Davis, K.R. and Spencer, W.F.
United States Department of Agriculture, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 358-363,
July 1974. 3 fig, 2 tab, 4 ref.
Descriptors: *Salinity, *Subsurface irrigation, *Irrigation practices, *Soil
water movement, Management, Agriculture, Irrigation.
Salt and water distribution patterns were determined around a porous tubing
as part of a study to evaluate several drip and subsurface irrigation lines at
Riverside, California. Generalized plot sampling after seasonal rainfall estab-
lished initial soil salinity and water levels. A detailed scheme was employed
50
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for mid-season and end-season soil sampling. Soil salinity and water distribu-
tions before, during, and after the 1973 growing season of zucchini squash are
discussed.
74:03F-022
DEVELOPMENT AND SCOPE OF DRIP AND SUBSURFACE IRRIGATION,
Deshmukh, M.T.
Udaipur University, India.
Proceedings of the Second International Drip Irrigation Congress, pp. 52-57,
July 1974. 31 ref.
Descriptors: Agriculture, Irrigation, Subsurface irrigation, Salinity, Saline
water
Drip irrigation is quite suitable for arid and semi-arid regions characterized
by poor saline soil, saline irrigation water, and high evapotranspiration rates.
In this method, water is applied slowly and continuously to the crops on the
ground surface with the help of pipes having perforations or emitters fixed
at suitable intervals along the length of the pipe. This paper reviews the
developments in the drip method of irrigation.
74:03F-023
EVALUATION OF HYDRAULICS OF FLOW THROUGH PIPES OF VARYING SLOPES, LENGTHS
AND ORIFICE PLACEMENTS,
Deshmukh, M.T. and Jain, M.L.
Udaipur University, India.
Proceedings of the Second International Drip Irrigation Congress, pp. 317-321,
July 1974. 2 fig, 1 tab, 8 ref.
Descriptors: *Hydraulic design, Agriculture, Irrigation, Hydraulics, Irrigation
design, Hydraulic equipment.
Polyethylene pipes with 1/2" diameter and 1/16" size perforations have been
used to study the hydraulics of flow, under laboratory conditions. The
variables considered for study were (i) length of the pipe (ii) spacing of per-
forations (iii) pipe slope (iv) placement of perforations (facing upward,
downward and sidewise) and (v) operating pressure (up to 5 ft.). Three
repeated readings have been taken for each test and validity of the results
showing relationship of discharge with variables considered has been established
with suitable tests.
74:03F-024
DRIP IRRIGATION IN LANDSCAPING AND SOIL EROSION CONTROL,
Farrell, M.D.
Kuluwai Irrigation Corporation, Haleiwa, Hawaii.
Proceedings of the Second International Drip Irrigation Congress, pp. 44-45,
July 1974.
Descriptors: *Soil erosion, ^Landscaping, Irrigation.
Article briefly discusses design, filtration, problems, and controls with drip
irrigation in landscaping situations.
74:03F-025
CLOGGING OF DRIP SYSTEMS FROM METABOLIC PRODUCTS OF IRON AND SULFUR BACTERIA,
Ford, H.W. and Tucker, D.P.H.
Florida University, Lake Alfred, Florida.
Proceedings of the Second International Drip Irrigation Congress, pp. 212-214,
July 1974.
Descriptors: *Clogging, *lron bacteria, *Sulfur bacteria, Irrigation, Agricul-
ture.
Numerous drip irrigation systems have been installed in central and south Florida
citrus groves. Many have ceased to function properly because of filter and
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emitter clogging. The most serious clogging, involving water from shallow and
deep wells, has been found associated with a sulfur bacteria. The long
filamentous bacteria, stuffed with sulfur from the oxidation of hydrogen
sulfide within the irrigation pipes, clog all small openings within a brief
period of time. The white, slimy organic-sulfur-iron mass can only be
dissolved in pyridine. Another serious clogging factor, from wells containing
traces of ferrous iron, has been a filamentous gelatinous iron deposit (ochre)
caused by iron bacteria. The sticky sludge adheres to filters and the grooves
and orifices of emitters.
74:-3F-026
DRIP IRRIGATIONS INHERENT REQUISITE - WATER QUALITY,
Eraser, G.O.
Scientific Irrigation Systems, El Monte, California.
Proceedings of the Second International Drip Irrigation Congress, pp.81-85,
Descriptors: *Coagulation, *Flocculation, *Filtration, Agriculture, Irrigation.
Article discusses reasons why water quality is of the utmost importance and
what factors cause deterioration of water quality. Methods of filtering
irrigation water are presented.
74:03F-027
AN EXPLANATION FOR THE GROWTH ADVANTAGE OF DRIP IRRIGATION,
Freeburg, R.S., Cotter, D.J., and Urquhart, N.S.
New Mexico State University, Las Cruces, New Mexico.
Proceedings of the Second International Drip Irrigation Congress, pp. 265-270,
July 1974. 2 fig, 3 tab, 6 ref.
Descriptorsi *Diurnal, *Temperature, *Soil temperature, *Furrow irrigation,
*Sweet corn, *crop Response, Agriculture, Irrigation, Irrigation practices.
Soil, leaf, and air temperatures were measured for sweet corn during a 16-day
period following emergence. The corn was grown in an experiment designed to
compare trickle (drip) irrigation to furrow irrigation. There were significant
differences between the temperature regimes produced by the two irrigation
methods. The effects were especially notable in the soil temperatures.
Based on a soil temperature of 80°F which research literature indicates to be
optimum for corn growth, an integrated deviation from optimum was computed for
each irrigation method. Deviations above the optimum at the two-inch depth
were only 785 degree-hours for the trickle system as compared to 1238 degree-
hours for the furrow system during the 16-day period. During this period, the
growth rate of the crop under furrow irrigation was 84 percent of that under
the trickle irrigation.
74:03F-028
EFFECTS OF NITROGEN FERTILIZER APPLICATIONS TO PART OF A ROOT SYSTEM,
Frith, G.J.T. and Nichols, D.G.
Victorian Department of Agriculture, Ferntree Gully, Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 434-436,
July 1974. 1 tab.
Descriptors: *Nitrogen, *Fertilization, *Apples,-*Root systems. Orchards,
Irrigation, Agriculture, Irrigation water.
It is usual under trickle irrigation of mature fruit trees to have considerably
less than the total root volume wetted. If satisfactory nutrition of these
trees is to be achieved with fertilizer dissolved in the irrigation water,
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then the wetted roots must increase their efficiency of nutrient uptake in a
manner similar to their increased water uptake. Trials with split root
seedling apple trees grown in water culture has shown that the nitrogen
uptake efficiency of roots is increased as the proportion of the root system
supplied with nitrate nitrogen is decreased. The efficiency of water uptake
from those parts of the root system supplied with nitrate nitrogen was also
increased over the level of uptake on quarters without nutrients.
74:03F-029
IRRIGATION FOR BENCHES,
Puruta, T., Besemer, S., Jones, W.C., Strohman, R., and Mock, T.
California University, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 149-154,
July 1974. 4 fig.
Descriptors: *Greenhouses, Horticultural crops, Agriculture.
A series of experiments were conducted on the modification of existing
irrigation systems and the use of drip irrigation for crops grown in benches.
Where the system was properly designed, excellent plant growth and yield
resulted from the use of modified nozzle irrigation systems, and from the use
of drip systems, both individual emitters and tubes with small orifices.
As measured by plant performance, water was more uniformly distributed in the
soil where drip or the modified nozzle system was used, compared to established
irrigation systems. Even with soils amended with large volumes of organic
matter, uniform distribution of water occurred, even though the surface
between emitters was dry. Also excellent crops were produced in a soil that
would be considered too tight or heavy for use in a bench. Considerable
savings on the amount of water used and a corresponding reduction of the
volume run-off resulted.
74:03F-030
IRRIGATION FOR CONTAINER GROWING,
Furuta, T., Branson, R., Jones, W.C., Strohman, R., Mock, T., and Ramadan, I.
California University, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 155-158,
July 1974.
Descriptors: *Nutrients, *Root development irrigation, Greenhouses, Salinity.
Trickle irrigation and modifications have been used for container growing,
especially under greenhouse conditions, for more than a decade. Microtubing
has been generally used. Difficulties with uniform wetting of the entire soil
mass had been encountered. This and other problems has limited the use of
trickle irrigation. With the development of emitters for containers, it
became possible to study the use of drip irrigation for container growing.
A series of experiments was conducted to study the soil mixture-fertilization-
irrigation subsystem, varying each factor simultaneously. Larger plants—tops
and roots—were noted under drip irrigation. These plants had higher N
content initially and lower Na and Cl content late in the experiment. Root
distribution within the container was also influenced with more roots in the
center of the ball. Considerably less water was used with drip irrigation
than with overhead sprinkling. The method of irrigation influenced salinity,
nutrient content of drainage water and the wetting pattern in the soil.
74 :03F-031
A CONSTANT MICRO SOURCE OF MOISTURE AS A COMPONENT ON A GRADIENT SYSTEM FOR A
HIGH LEVEL PRODUCTION,
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Geraldson, C.M.
Florida University, Bradenton, Florida.
Proceedings of the Second International Drip Irrigation Congress, pp. 131-136,
July 1974. 4 fig, 4 ref.
Descriptors: *Nutrients, Agriculture, Irrigation.
The objective of this study was to evaluate the use of a constant micro source
of moisture which could be used as an alternative to a constant water table
in establishing nutrient gradients for optimal production. Constant moisture
was supplied by drip (trickle system) or by micro pore tubing. Soluble
nutrients were supplied primarily by banded placement on the soil bed surface.
Relative placement of fertilizer, moisture and plants as the major variables
were evaluated in conjunction with different soils as well as the sources of
moisture. A consistent high level production of vegetables and flowers was
attained by integrating contributing components such as soil, moisture,
fertilizer and plants to establish the desired gradient system. The resultant
effect in conjunction with synthetic mulch as a protective component minimizes
or eliminates these components as contributing variables.
74:03F-032
DRIP AND FURROW IRRIGATION STUDIES ON SUGARCANE,
Gerard, C.J.
Texas Agricultural Experiment Station, Weslaco, Texas.
Proceedings of the Second International Drip Irrigation Congress, pp. 329-331,
July 1974. 3 ref.
Descriptors: *Sugarcane, *Furrow irrigation, *Crop response, Texas, Irrigation,
Agriculture.
Research was conducted to evaluate the influences of drip and furrow irrigation
on growth and yield of sugarcane in 1972 and 1973 in the Lower Rio Grande
Valley of Texas. Drip irrigation treatments were 0, 25, 50, 75, and 100 and 0,
50, 75, 100, and 125% pan evaporation in 1972 and 1973, respectively. Yield
of sugarcane was a linear function of applied water in 1972 with yields ranging
from 35 to 51 tons per acre. Drip irrigation treatments are greater than or
equal to 0.5 pan evaporation maintained rapid stalk elongation in early May and
June in 1972. Rapid stalk elongation in July, August and September was
maintained when the water applied was greater than or equal to 0.75 pan
evaporation. Soil moisture, salinity conditions and root growth as influenced
by treatments, emitter sites and soil depths were evaluated. These findings
and their implications are discussed.
74:03F-033
HYDRAULIC AND MECHANICAL PROPERTIES OF DRIPPERS,
Gilaad, Y., Krystal, L., and Zanker, K.
Israel Center of Water Works Appliances, Tel-Aviv, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 311-316,
July 1974. 1 tab.
Descriptors: *Hydraulic properties, *Hydraulic equipment, *Hydraulic design,
*Mechanical properties, Hydraulics, Agriculture, Irrigation.
Article discusses research dealing with the hydraulic, mechanical, and
functional requirements of the various types of emitters available based on
hydraulic tests performed and experience accumulated in the field. The
following hydraulic properties have a direct influence of the operation of
drippers: the relationship between flow rate and pressure, resistance to the
flow of water in the tubing at the place of insertion of the dripper, and
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shape and size of the water passage in the dripper.
74:03F-034
OPTIMUM LATERAL PLACEMENT FOR SUBSURFACE IRRIGATION SYSTEMS,
Gilley, J.R. and Allred, E.R.
Minnesota University, St. Paul, Minnesota.
Proceedings of the Second International Drip Irrigation Congress, pp. 234-239,
July 1974. 6 ref.
Descriptors: *Subsurface irrigation, *Mathematical models, *Irrigation design,
Irrigation, Irrigation efficiency, Irrigation systems. Agriculture.
Design of a subsurface irrigation system requires both the proper placement of
the lateral line in the soil profile and proper lateral discharge. The
lateral placement depends on the nature of the soil-moisture movement from the
applicator and the extraction pattern of the irrigated crop. The optimum
location of the laterals will therefore vary with soil type and the crop being
irrigated. A mathematical model describing soil-moisture movement during
subsurface irrigation has been developed. The results of the portion of the
model describing infiltration from the subsurface lateral compare quite
favorably with data available in the literature. A series of one dimensional
sinks, to simulate soil-moisture extraction by plants, has been combined with
the infiltration model to obtain a model of soil-moisture movement during
subsurface irrigation. The model was used to determine optimum lateral
placement as a function of soil type and crop root zone depth to obtain the
desired crop extraction patterns. Results of the model indicate the optimum
lateral placements also have higher irrigation efficiencies than other
placement values. These variables were used to develop design curves relating
lateral depth, spacing and discharge to soil type and crop extraction pattern.
Results also indicate that for proper design, lateral depth is more important
than lateral spacing.
74:03P-035
STRIP CULTIVATION OF THE AREA WETTED BY DRIP IRRIGATION IN THE ARAVA DESERT,
Goldberg, S.D. and Uzrad, M.
The Hebrew University of Jerusalem, Rehovat, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 142-147,
July 1974.
Descriptors: *Strip cropping, *Saline water, *Salinity, *Sprinkler irrigation.
Melons, Irrigation practices, Irrigation, Agriculture.
Drip irrigation cultivation is in effect strip cultivation and in fact it
represents almost the most intensive form of cultivation. Throughout the
growing season the cultivated strip gets a most intensive set of treatments.
Under arid climatic conditions in light soils and with saline water (like in
the Arava), it is safe to assume that these strips will undergo considerable
chemical changes which would materially differ from the intermediary uncultivated
strips. The problem posed was whether the cultivated strips were better, or
worse, or of no difference compared to the uncultivated strips. Results show
that the cultivated strips were superior to the uncultivated strips.
74:03F-036
FERTILIZER APPLICATIONS WITH DRIP IRRIGATION,
Grobbelaar, H.L. and Lourens, F.
Agriplas Limited, Republic of South Africa.
Proceedings of the Second International Drip Irrigation Congress, pp. 411-415,
July 1974. 3 tab.
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Descriptors: *Fertilization, *Irrigation practices, Irrigation, Agriculture.
It has been found that the application of fertilizer mixtures through a drip
irrigation system is not only feasible, but can be very beneficial. Fertilizer
mixtures must not cause blockage, must be water soluble, must leave no
residue in the fertilizer dispenser, and must be easy to handle.
74:03F-037
RESEARCHES AND APPLICATIONS ON DRIP IRRIGATION AND SIMILAR METHODS IN ITALY,
Grossi, P.
Pisa University, Pisa, Italy.
Proceedings of the Second International Drip Irrigation Congress, pp. 46-51,
July 1974.
Descriptors: Irrigation systems, Agriculture, Irrigation.
Research progress with trickle irrigation is discussed along with the hydraulic,
pedological, and agronomical results of this research.
74:03F-038
DRIP IRRIGATION-WORLDWIDE,
Gustafson, C.D., Marsh, A.W., Branson, R.L., and Davis, S.
California University, San Diego, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 17-20,
July 1974. 1 fig.
Descriptors: *History, *Irrigation practices. Irrigation systems.
Water is a precious commodity. Good water supplies are always in demand.
All around the world, problems with water are: short supply, poor quality and/
or expensive. In reviewing the development of drip irrigation, it is apparent
that the greatest interest is in areas where there is a problem with water
supplies. Poor soils or steep terrain also encourages the use of drip irriga-
tion. Drip irrigation is not new. It has been used for years. What is new,
however, is its application to modern agriculture. On a commercial scale in
the United States, it can be traced back to 1969-70. That was not the
beginning, however, since many industries have been using some type of drip
irrigation for a long time. Drip irrigation had its beginning in the green-
house culture after World War II in the United Kingdom. In the late 1950's and
early 60's, Richard Chapin, New York; Dr. Symcha Blass, Israel; and Dr. Vollmer
Hansen, Denmark, simultaneously were perfecting what is commonly known as the
spaghetti system.
74:03F-039
DRIP IRRIGATION EXPERIMENT ON AVOCADOS,
Gustafson, C.D., Marsh, A.W., Branson, R.L., and Davis, S.
California University, San Diego, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 443-445,
July 1974.
Descriptors: *Crop response, *Crop productivity, *Salinity, Sprinkler irrigation,
Cost comparisons, Diseases, Irrigation, Agriculture.
In June 1970, an irrigation project was initiated to compare drip irrigation
with the conventional spitter-sprinkler system, commonly used in avocado
orchards. Evaluation of the two methods include: 1) a comparison of growth
and productivity; 2) salinity accumulation and distribution in soils under
each system; 3) annual costs to operate each system; 4) determine if trees are
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more or less susceptible to the avocado root rot disease; and 5) observe
operation of equipment.
74:03P-040
STAKED TOMATO DRIP IRRIGATION IN CALIFORNIA,
Hall, B.J.
California University, San Diego, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 480-486,
July 1974. 6 tab, 6 ref.
Descriptors: *Tomatoes, Furrow irrigation, Irrigation systems, Irrigation
practices, Crop response, Irrigation, Agriculture .
Six staked tomato drip irrigated field trials, where properly grown, resulted
in slightly higher yields and appreciable water savings, compared to furrow
applications. Drip irrigation supplied water more uniformly which resulted
in more even plant growth. Cultural operations can be carried out in the drip
irrigated crops at any time, while close coordination of these operations is
essential when using furrow or sprinkler irrigations.
74-.03F-041
SPRING CUCUMBER DRIP VS. FURROW IRRIGATION,
Hall, B.J.
California University, San Diego, California.
Proceedings of the Second International Drip Irrigation Congress,pp. 486-490,
July 1974. 1 tab, 6 ref.
Descriptors: *Fertilization, *Furrow irrigation, *Crop response, Irrigation,
Agriculture.
Two field trials conducted on the early spring cucumbers started and grown
in plastic row covers indicate that drip irrigation can successfully produce
good yields. Less water can be used in producing as high or better yields
with drip irrigation. Slow release fertilizer resulted in good yields, yet
the plants appeared to run short during the last two or three weeks. Placing
the drip line in the bottom of a 1 1/2 to 2-inch narrow furrow appeared to
reduce the mature fruit pressure on the drip lines in bush culture.
74:03F-042
VEGETABLE PRODUCTION AND WATER-USE EFFICIENCY AS INFLUENCED BY DRIP, SPRINKLER,
AND FURROW IRRIGATION METHODS,
Hanson, E.G. and Patterson, T.C.
New Mexico University, Las Cruces, New Mexico.
Proceedings of the Second International Drip Irrigation Congress, pp. 97-102,
July 1974.
Descriptors: *Sweet corn, *Onions, *Crop response, *Irrigation practices,
*Vegetable crops, *Irrigation systems, *Sprinkler irrigation, *Subsurface
irrigation, *Furrow irrigation, *Soil moisture, Salinity, Irrigation,
Agriculture.
Sweet corn and onions have been grown on replicated plots with four methods
of irrigation: drip, subsurface, sprinkler, and furrow. Half of the plots
have been irrigated to maintain the soil moisture tension at or below 0.20
atmospheres, and the other half at or below 0.60 atmospheres. Yield, quality,
and water-use efficiency pertaining to each crop is reported for three growing
seasons. Changes in soil salinity are discussed.
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74:03F-043
DRIP IRRIGATION DESIGN CRITERIA FOR TREE CROPS IN FLORIDA AND OTHER HUMID
REGIONS,
Harrison, D.S. and Myers, J.M.
Florida University, Gainsville, Florida.
Proceedings of the Second International Drip Irrigation Congress, pp. 33-37,
July 1974. 11 ref.
Descriptors: *Orchards, *Crop response, *Florida, *Humid area, Irrigation
practices, Citrus fruits, Irrigation, Agriculture, Irrigation systems,
Irrigation design.
Drip irrigation has been installed on approximately 4,000 acres of citrus and
other orchard crops in Florida during the past 2 years. Some of the reasons
for increased interest in this method of irrigation are: (1) conservation of
water, (2) labor savings, (3) lower operating costs, and (4) lower power
requirements. Some problems are: (1) improper water filtration, (2) research
data on crop response not readily available, (3) vandalism, (4) unavailability
of fully tested design criteria, (5) emitter spacing, and (6) expected life.
Two years research data in Florida on strawberries, and one year on tomatoes
show that response to drip irrigation is comparable to other application
methods and water savings as much as 60-70% may be expected. Fertilizer
response, when applied through the drip system, has been outstanding.
74:03F-044
PLANT WATER REQUIREMENTS AS RELATED TO TRICKLE IRRIGATION,
Hoare, E.R., Garzoli.K.V., and Blackwell, J.
Proceedings of the Second International Drip Irrigation Congress, pp. 323-328,
July 1974. 3 tab, 10 ref.
Descriptors: *Water requirements, Irrigation systems, Irrigation design,
Irrigation practices, Irrigation, Agriculture.
Trickle irrigation differs from spray and flood irrigation in that water is
supplied in small amounts at frequent intervals in order to satisfy, as
closely as possible, the plants' immediate needs. This is in contrast to other
forms of irrigation in which large quantities of water are supplied, following
which a gradual drying of the soil takes place, and subsequent irrigation is
carried out to replenish the reservoir of soil moisture. The difference in
these two approaches to irrigation means that current methods of estimating
the water requirements of crops requires further evaluation. Not only does
the water requirement vary with different climatic conditions, age of the
plants and the season, irrespective of the method of irrigation, but the use
of trickle irrigation imposes a further variation due to its particular
effect on the soil-plant-atmosphere complex. The water requirements of plants
under trickle irrigation are examined and ways are suggested in which these may
be calculated from evaporation data, soil properties and other characteristics
specific to the particular crop. Reference is also made to the use of trickle
irrigation in particular situations, and how the water requirements in such
cases can best be satisfied.
74:03F-045
SALINITY MANAGEMENT FOR HIGH FREQUENCY IRRIGATION,
Hoffman, G.J., Rawlins, S.L., Oster, J.D., and Merrill, S.D.
United States Department of Agriculture, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 372-375,
July 1974. 4 fig.
Descriptors: *Salinity, *Saline soil, *Saline water, *Leaching, Grain sorghum,
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Lettuce, Wheat, Crop response, Irrigation practices. Irrigation, Agriculture.
A field plot experiment designed to determine the minimum leaching required to
maintain crop yields under high frequency irrigation is described. Two
varieties of wheat, grain sorghum, and lettuce are being grown in rotation
each year in six replicated leaching fraction treatments. Precise measurements
of the volume and salt concentration of the irrigation and drainage waters
along with in-situ soil salinity measurements and crop yield are reported.
74s03F-046
DESIGNING TRICKLE IRRIGATION LATERALS FOR UNIFORMITY,
Howell, T.A. and Hiler, E.A.
Texas University, College Station, Texas.
Proceedings of the Second International Drip Irrigation Congress, pp. 299-304,
July 1974. 3 fig, 6 ref.
Descriptors! *Uniformity coefficient, *Uniform flow, *Irrigation design,
Irrigation systems, Design criteria, Design flow, Irrigation, Agriculture.
Proper design of trickle irrigation laterals for desired uniformity is
important to prevent under-irrigation, with resulting crop damage, or over-
irrigation, with resulting water losses of drainage and runoff. Recently
several papers have presented trickle irrigation design data and methods; yet
a simple design equation for directly determining maximum lateral lengths for
different lateral slopes, trickle emitter types, pipe sizes, and desired
uniformity is not available. Design equations, based on standard principles,
fluid mechanics, and graphs are presented which can be used to determine
maximum trickle irrigation lateral lengths for selected uniformities. The
maximum lateral length for a given uniformity is given as a power function
(linear log-log) of either emitter spacing of number of emitters per lateral.
Engineering design applications for this method are given in the form of
specific examples. Implications and assumptions inherent in the method are
discussed.
74:03F-047
INVESTIGATIONS IN SUGARCANE FERTILIZATION BY DRIP IRRIGATION IN HAWAII,
Isobe, M.
Hawaiian Sugar Planters Association, Honolulu, Hawaii.
Proceedings of the Second International Drip Irrigation Congress, pp. 405-510,
July 1974. 3 tab.
Descriptors: "Sugarcane, ^Fertilization, Hawaii, Nitrogen, Subsurface
irrigation, Irrigation practices. Irrigation, Agriculture.
Research was initiated in Hawaii to determine efficient ways to fertilize
sugarcane under drip irrigation. Paper reports on improvement of fertilizer
efficiency and the use of aqua ammonia, the cheapest source of nitrogen
available on the market.
74t03F-048
EVALUATION OF A TRICKLE IRRIGATION SYSTEM,
Karmeli, D. and Keller, J.
Technion, Haifa, Israel.
proceedings of the Second International Drip Irrigation Congress, pp. 287-292,
July 1974. 1 tab.
pescriptors: "Uniformity, Soil moisture, Evaluation, Performance, Filtration,
Irrigation practices, Irrigation efficiency, Irrigation operation and
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maintenance, Irrigation systems. Irrigation, Agriculture.
Factors determining performance of the system i.e. filtration quality,
pressure and soil moisture distributions, are analyzed. Techniques for the
evaluation of a system design or field performance are described and an
equation to calculate the emission uniformity, EU, of a trickle system is
presented. Results of field tests and design evaluations are summarized and
criteria established. Relationships between EU and soil volume values as well
as irrigation regimes (application rates and intervals) are discussed.
74:03F-049
TRICKLE IRRIGATION DESIGN FOR OPTIMAL SOIL WETTING,
Keller, J. and Karmeli, D.
Utah State University, Logan, Utah.
Proceedings of the Second International Drip Irrigation Congress, pp. 240-245,
July 1974. 2 fig, 2 tab, 3 ref.
Descriptors: *Irrigation design. Soil moisture, Evapotranspiration. Plow rates.
Design criteria, Economics, Irrigation, Agriculture.
The general relationship between the percentage area wetted and crop
productivity is discussed and the recommended trickier spacing for achieving
the desired soil wetting is presented. The number of operating blocks
(stations or sub-units) required to obtain the desired soil wetting is
developed considering ET demands and system capacity constraints. The effect
of the number of blocks on hydraulic features of the network and the relative
economic effect is considered.
74:03F-050
TRICKLE IRRIGATION IN MICHIGAN ORCHARDS,
Kesner, C.D. and Kenworthy, A.L.
Michigan State University, East Lansing, Michigan.
Proceedings of the Second International Drip Irrigation Congress, pp. 272-274,
July 1974.
Descriptors: Irrigation practices, Irrigation systems, Michigan, Orchards.
The concept of trickle irrigation is being rapidly accepted by Michigan fruit
growers. A major source of water is from small existing wells previously used
for cooling sour (red tart) cherries at harvest time and other purposes. Lakes,
ponds, rivers, and creeks also serve as water sources. Pressure regulators
or gate valves were originally used to control in-line pressure but the
present trend is toward flow regualting valves in each row lateral. The
primary emitter system in Michigan is the microtube with .025, .035, .036, or
.045 inch I.D. tubes being the most popular. An illustrated presentation
demonstrates the techniques used in many different installations.
74:03F-051
WEED CONTROL UNDER DRIP IRRIGATION IN ORCHARD AND VINEYARD CROPS,
Lange, A., Aljibury, P., Fischer, B., Humprey, W., and Otto, H.
Proceedings of the Second International Drip Irrigation Congress, pp. 422-424,
July 1974.
Descriptors: *Herbicides, Orchards, Irrigation practices, Irrigation,
Agriculture.
Conventional herbicide applications in orchards and vineyards under drip
irrigation have been somewhat unsuccessful. Annual applications of most
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herbicides have broken down in the moist area close to the dripper Leaving a
vigorous small circle of weed growth by summer. Herbicides differ in their
rates of breakdown under drip irrigation when compared to furrow and sprinkler.
Atrazine showed the greatest response to breaksown under continuously wet
soils. Napropamide was affected least bu wet soils. Trifluralin, profluralin,
and norflurazon were intermediate. Numerous herbicide treatments have been
evaluated under drip irrigation. The results of several of these are discussed.
74:03F-052
SOIL MOISTURE DISTRIBUTION AND DEPLETION IN AN APPLE ORCHARD IRRIGATED BY
TRICKLERS,
Levin, I., Assaf, R., and Bravado, B.
The Hebrew University of Jerusalem, Rehovat, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 252-257,
July 1974. 4 fig, 1 tab, 4 ref.
Descriptors: Irrigation practices, *Soil water movement, Irrigation systems,
Frequency, Orchard, Apples, Crop response, Irrigation, Agriculture.
Four treatments of trickle irrigation methods were applied in an apple orchard
on heavy soil. The treatments differed in water discharge rate of the
tricklers (4 and 8 liter/hour), distances between the outlets on the lateral
lines (1.25 m and 2 m) and irrigation frequency (1, 3 and 7-day intervals).
In all treatments the amount of water applied was on the basis of 10 mm/day
consumptive use. Soil moisture content fluctuations in the upper 60 cm layer
before, during and after irrigation were frequently measured. The distance
wetted from the trickier was linearly dependent on the duration of the single
irrigation and the discharge rate of the trickier: 65 cm, 80 cm, and 120 cm
after 14, 24 and 70 hours of irrigation at a 4 liter/hour discharge rate,
respectively; and 120 cm after 40 hours at a 8 liter/hour discharge rate. The
soil moisture content at the end of the irrigation dropped gradually from
under the trickier to the farthest distance wetted, where about 90% of field
capacity was reached. After the termination of the irrigation, the soil
moisture content depleted gradually to the level before the beginning of the
irrigation - at all distances from the tricklers and in all treatments. The
results indicate that there was deep drainage below the root zone in the area
under the tricklers in all treatments.
74:03F-053
APPLICATION OF FERTILIZER THROUGH DRIP IRRIGATION SYSTEMS IN WEST TEXAS,
Lindsey, K.E.and New, L.L.
Texas University, Lubbock, Texas.
proceedings of the Second International Drip Irrigation Congress, pp. 400-404,
July 1974.
Descriptors: *Fertilization, *Pecans, Irrigation systems, Zinc, Crop response,
irrigation, Agriculture.
Zinc chelate applications to pecan trees were made through several types of
systems on several soil types. Comparisons were made with customary spray
applications of Zn. Effectiveness of applications was measured by leaf
analysis and trunk growth measurements. Examination of the effectiveness
Of several of the injection systems was done by analyzing water emitted at
timed intervals after injection of Zn materials.
74:03F-054
EFFECTS OF DRIP IRRIGATION ON SOIL-WATER-PLANT RELATIONSHIP,
Manfrinato, H.A.
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Escola Superior de Agricultura, Sao Paulo, Brazil.
Proceedings of the Second International Drip Irrigation Congress, pp. 446-451,
July 1974. 1 fig, 4 tab, 9 ref.
Descriptors: *Infiltration, *Moisture content, *Soil water movement, *Soil-
water-plant relationships, Agriculture.
Soil columns, prepared in the laboratory, by packing sieved and air dried soil
into cylinder tubes were used to study the distribution of moisture content at
the moment of infiltration. Drops of water, were applied simulating rain, at
eight differernt intensities, called treatments, with two repetitions. When
the water application rate was continually reduced throughout the treatments,
the moisture content also diminished and vice versa. It was also concluded
that when the rain application intensity was decreasing to a very small rate,
the moisture content had such a slow reduction, as if going to a limit, which
was found to be the soil field capacity.
74:03F-055
WATER USE BY DRIP AND SPRINKLE IRRIGATED AVOCADOS RELATED TO PLANT COVER,
EVAPORATION AND AIR TEMPERATURE,
Marsh, A.W., Gustafson, C.D., Davis, S., Branson, R.L., and Strohman, R.A.
California University, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 346-350,
July 1974. 2 tab, 5 ref.
Descriptors: *Consumptive use, *Sprinkler irrigation, *Air temperature,
*Evaporation, Tensiometers, Irrigation systems. Irrigation practices. Irrigation
Agriculture.
Water application to the avocados has been closely controlled by relating it
to tensiometer readings. A sufficiency has been maintained while limiting
excesses. In 1973, the drip applications have been automatically controlled by
electrified tensiometers that provide signals for a controller. The measured
applications are thought to represent the actual water requirement for each
irrigation system as closely as it can be determined. The correlation of
measured water use to evaporation from a class A pan is shown for each
irrigation method as influenced by varying air temperature, percentages of
plant cover, and period of the year.
74:03F-056
CHEMICAL TREATMENT OP DRIP IRRIGATION WATER,
McElhoe, B.A. and Hilton, H.W.
Hawaiian Sugar Planters' Association, Honolulu, Hawaii.
Proceedings of the Second International Drip Irrigation Congress, pp. 215-220,
July 1974. 2 fig, 2 tab.
Descriptors: *Microorganisms, *Bacteria, *Plugging, *Orifice flow, *Orifices,
Irrigation, Agriculture, Irrigation efficiency. Irrigation systems, Irrigation
water.
Bacteria and other microorganisms in water are contributors to orifice
plugging. Their skeletons, the slimes they produce, and their metabolic
products are the glue that binds fine soil particles to the walls of the tube.
Chenical treatment can arrest the agglomeration process and significantly
reduce plugging.
74:03P-057
AN INVESTIGATION ON THE USE OF DRIP IRRIGATION FOR THE ESTABLISHMENT OF MULTI-
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PURPOSE PARKS (GREEN BELTS AROUND THE CITIES) IN IRAN,
Mehdizadeh, P. and Tamaddoni-Jahromi, S.
Research Institute of Forests and Rangelands, Tehran, Iran.
Proceedings of the Second International Drip Irrigation Congress, pp. 462-468,
July 1974. 5 fig, 2 tab.
Descriptors: *Furrow irrigation, *Crop response, *Parks, Irrigation, Irrigation
systems, Irrigation practices, Forestry, Forests, Forest management.
paper deals with the application of a "home-made" drip irrigation system in a
multipurpose forest park near Tehran. The study was initiated as a pilot
trial to determine: (1) if drip irrigation should be considered for irrigating
forest species in the parks.and green belts, of Iran, (2) plant responses to
drip irrigation of green belts, and (3) possible water savings . Although
some suppression of height growth was found, seedlings remained healthy. The
amount of irrigation water used was reduced by 85% as compared to the furrow
irrigation system used previously.
74:03F-058
TREE AND CROP RESPONSE TO DRIP IRRIGATION,
Middleton, J.E., Proebsting, E.L., Roberts, S., and Emerson, F.H.
Washington State University, Prosser, Washington.
proceedings of the Second International Drip Irrigation Congress, pp. 468-473,
July 1974. 5 fig, 3 tab, 3 ref.
Descriptors: *Orchards, *Crop response, *Fruit crops, Salinity, Irrigation
system, Irrigation practices, Irrigation, Agriculture.
Bearing "Early Italian" prune trees performed normally with 60 and 80 gallons
per tree per day using continuous drip irrigation. With 20 and 40 gallons per
tree per day the fruit was smaller, better colored and earlier with higher
soluble solids. In the second year, the two lower rates greatly reduced
bearing surface and yields. Leaf moisture data indicated no difference on the
four quadrants of the tree when all water was applied at one point. Twelve
hour daily applications were compared to continuous applications the second
year. There were some soluble salts on the non-saline soil which were reduced
measurably by movement away from the center of the drip area as the season
progressed. Soil moisture movement was recorded. Growth response of first
year apple trees to drip and sprinkler irrigation at comparative application
frequencies and amounts was similar.
74:03F-059
TRICKLE IRRIGATION ON YOUNG PEACH TREES,
Mitchell, P.O. and Black, J.D.F.
Victorian Department of Agriculture, Ferntree Gully, Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 452-455,
July 1974. 8 fig.
Descriptors: *Peaches, *Crop response, *Growth rates, Root distribution,
Evaporation, Orchards, Irrigation systems, Irrigation practices, Irrigation,
Agriculture.
Two field trails on young peach trees are described. Trial A. The effects of
supplyin
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74:03F-060
AUTOMATIC DRIP IRRIGATION FOR GREENHOUSE TOMATO PRODUCTION IN WEST TEXAS,
New, L. and Roberts, R.
Texas A&M University, Lubbock, Texas.
Proceedings of the Second International Drip Irrigation Congress, pp. 159-164,
July 1974. 1 fig.
Descriptors: *Crop response, *Tomatoes, *Automatic control, *Autornation,
Greenhouses, Irrigation systems, Irrigation, Agriculture.
Soil moisture sensors are used to automatically control the operation of drip
irrigation systems and maintain optimum moisture levels in West Texas tomato
greenhouses. Up to ten thousand square feet of growing area is being
successfully irrigated by one sensor. Time clocks cause intermittent
irrigation which helps prevent overwatering., puddling and runoff. Water flow
control valves limit drip emitter water application rates to 1.0 to 1.5 gallons
per hour.
74:03F-061
A STUDY ON DIFFERENT APPLICATION PROCEDURES OF DRIP IRRIGATION ON TOMATO
CULTIVATION,
Noyola, F.T.
Proceedings of the Second International Drip Irrigation Congress, pp. 508-511,
July 1974.
Descriptors: *Tomatoes, *Crop production, *Crop response, Irrigation systems,
Irrigation practices, Irrigation, Agriculture.
Article discusses results of a study on tomatoes to determine reasonable
application procedures of drip irrigation water.
74:03F-062
DRIP IRRIGATION AND AUTOMATION TOOLS IN EFFICIENT USE OF WATER POLICY,
Paldi, H.
Ministry of Agriculture, Safad, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 29-32,
July 1974.
Descriptors: *Automation, *Water policy, *Water conservation, Irrigation
systems, Irrigation, Agriculture.
Article discusses water savings in Israel with drip irrigation, long range
irrigation plans for Israel, and irrigation system automation^.
74:03F-063
IRRIGATION RETURN FLOW AS INFLUENCED BY DRIP IRRIGATION,
Patterson, T.C. and Wierenga, P.J.
New Mexico State University, Las Cruces, New Mexico.
Proceedings of the Second International Drip Irrigation Congress, pp. 276-381,
July 1974. 2 fig, 3 tab, 4 ref.
Descriptors: *Return flow, *Water quality, *Salinity, *Surface irrigation,
*Saline water, *Saline soil. New Mexico, Texas, Irrigation practices,
Irrigation systems, Irrigation, Agriculture.
Deterioration of water quality in the Rio Grande is a major problem for water
users in New Mexico and Texas. From near Santa Fe, New Mexico to El Paso,
Texas, a distance of 270 miles, the total of dissolved solids increases from
221 ppm to 787 ppm while while the percent of sodium increases from .25 near
Santa Fe to 52 at El Paso. The deterioration in quality is due to the return
of lower quality drainage water from the irrigated areas to the river. This
paper describes a project designed to determine, under field conditions, rates
of water and salt movement in the soil and subsequently to the drains as
affected by frequency and amount of trickle irrigation, as compared to frequency
and amount of surface water application. Both return flow quality and
quantity are evaluated.
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74:03F-064
FORMATION OF BLOCKAGES IN DRIP IRRIGATION SYSTEMS: THEIR PREVENTION AND
REMOVAL,
Pelleg, D. , Lahav, N. , and Goldberg, D.
Israel Center of Waterworks Appliances, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 203-208,
July 1974. 8 fig, 3 tab, 6 ref.
Descriptors: *Clogging, Irrigation systems, Irrigation practices. Irrigation,
Agriculture.
Clogging is one of the most severe problems associated with trickle irrigation
systems. The different kinds of clogging are described along with the
reasons for clogging. Methods of preventing clogging are given, and ways of
cleaning systems after clogging has occurred are discussed.
74:03F-065
HIGH-FREQUENCY POROUS TUBE IRRIGATION FOR WATER-NUTRIENT MANAGEMENT IN HUMID
REGIONS ,
Phene, C.J.
United States Department of Agriculture, Florence, South Carolina.
Proceedings of the Second International Drip Irrigation Congress, pp. 166-171,
July 1974. 6 fig, 1 tab, 8 ref.
Descriptors: *Sweet corn, *Crop response, ^Subsurface irrigation. Nitrogen,
Automation, Irrigation efficiency, Nutrients, Furrow irrigation, Sprinkler
irrigation, Irrigation practices, Irrigation systems.
A plastic porous tube and an electronic soil matric potential sensor supplied
sweet corn with nutrients and water automatically by controlling the water
content of a limited volume of root-zone soil. Sweet corn yield and water-use
efficiency obtained with high-frequency porous tube irrigation systems were
compared with those obtained from high-frequency sprinkler and furrow irrigation
systems under similar irrigation control and fertility. In another experiment,
sweet corn yield, plant nitrogen uptake, and soil NO3(-) movement were studied
under controlled soil matric potential for various application rates of N and K.
Ear yield with high-frequency porous tube irrigation was 10.5 and 12.6% greater
than ear yield obtained with furrow and sprinkler irrigation, respectively.
Water-use efficiency was 37 and 54% higher for sensor controlled high-frequency
porous tube irrigation than for furrow and sprinkler irrigation.
74:03F-066
METHOD FOR DRIP IRRIGATION SYSTEM DESIGN AND INSTALLATION PROCEDURE,
pira, E.S.
Massachusetts University, Amhurst, Massachusetts.
proceedings of the Second International Drip Irrigation Congress, pp. 121-126,
July 1974. 4 fig, 2 tab, 2 ref.
Descriptors: *Head loss, * Design criteria, *Irrigation design, Irrigation
methods, Flow rates. Irrigation, Agriculture.
High pressure water is supplied through a "quick-fill" and pressure reducing
device to a low pressure chamber. A minimal pressure drop in the chamber
oroduced a relatively uniform discharge rate from the drippers. This paper
deals with the practical field installations based on laboratory tests, field
tests and simulation model. System design criteria, components, materials,
detailed illustrations and installation procedures are presented.
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74:03F-067
MOVEMENT OF WATER AND SALTS UNDER HIGH FREQUENCY IRRIGATION,
Raats, P.A.C.
United States Salinity Laboratory, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 222-227,
July 1974. 5 fig, 14 ref.
Descriptors: *Soil water movement, *Salinity, *Infiltrationr Irrigation systems,
Irrigation, Agriculture.
Many modern irrigation systems deliver water at short intervals, in space as
well as in time. Theoretical analyses show that the remaining variations are
damped rapidly. Consequently, steady, one-dimensional movement and uptake is
used as a basis for further analysis. Qualitative features of possible steady
pressure head and water content profiles are discussed. Specific calculations
for various leaching fractions and amounts of capilary rise from a water table
are based on empirical, but realistic models for the dependence of the
hydraulic conductivity upon the pressure head and for the spatial distribution
of the rate of uptake. The resulting salinity profiles are also calculated.
The results are compared with earlier, more approximate calculations.
74:03P-068
THE PROGRESS AND PROBLEMS OF DRIP IRRIGATION IN ISRAEL,
Rawitz, E. and Hillel, D.
The Hebrew University of Jerusalem, Rehovat, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 23-28,
July 1974. 18 ref.
Descriptors: Crop response, Design criteria. History, Irrigation, Irrigation
system, Irrigation practices. Agriculture.
The "state of the art" of drip irrigation in Israel is reviewed regarding both
equipment and operational practices. Equipment available on the market is
generally reliable and conforms to manufacturer's specifications of hydraulic
properties. Filtering and clogging of small discharge orifices remains a
problem under certain conditions. A standard head has been developed for
connection to the main system incorporating filter, vacuum breaker, fertilizer
applicator, pressure regulator, and automatic valves. Hydraulically or
electrically actuated automatic valves are used either singly or for sequential
operation. Many growers have reported excellent results with drip irrigation
of orchards, truck crops, and flowers. The relative advantages of drip
irrigation are especially pronounced where relatively saline water must be used
under extremely arid conditions. Criteria and recommendations have yet to be
determined regarding irrigation frequency and application amounts in relation
to emitter spacing and discharge, and percent of wetted area for different
crops, soil profile characteristics, climatic conditions, and water quality.
Some consequences of improper operation may be under-irrigation, excessive
restriction of the root zone, and excessive leaching of water and nutrients
below the rooting depth.
74:03F-069
REVERSE FLUSHING TECHNIQUE FOR BI-WALL DRIP TUBING,
Rawlins, S.L.
United States Salinity Laboratory, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 209-211,
July 1974. 2 fig.
Descriptors: *Clogging, Irrigation, Agriculture, Irrigation systems.
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Particles carried in the irrigation water first lodge in the inside orifices
between the supply and emission chambers of biwall drip tubing. These can be
effectively dislodged by briefly applying water at high pressure to the
emission chamber. They can then be flushed from the supply chamber in the usual
manner. Because the burst pressure of tubing varies inversly with its diameter,
the small emission chamber can withstand considerably higher pressures than
can the supply chamber. Results of tests using this technique are discussed.
74:03F-070
TRAVELING TRICKLE SYSTEM,
Rawlins, S.L., Hoffman, G.J., and Merrill, S.C.
United States Salinity Laboratory, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 184-187,
July 1974.
Descriptors: Irrigation design, Cost comparisons, Cost analysis, Irrigation,
Irrigation systems. Irrigation practices. Agriculture, Sprinkler irrigation.
Typical drip irrigation systems deliver frequent applications of small volumes
of water by using a large number of small diameter orifices installed along
tubes. The long lengths of tubes and large number of emitters required make
drip irrigation costly for row crops. In addition, the small diameter of the
orifices required to control water flow in such a system makes it susceptible
to plugging and adds an additional filtration expense. We describe a traveling
trickle system that circumvents both of these problems by controlling water
application with a few large orifices moved along the row rather than with a
large number of fixed location orifices. Results are presented from cost
analyses for large-scale systems by converting standard center pivot sprinkler
irrigation systems.
74:03F-071
USE OF GLYCEROPHOSPHATE FOR FERTILIZATION THROUGH TRICKLE IRRIGATION SYSTEMS,
Rolston, D.E., Ravschkolb, R.S., and Hoffman, D.L.
California University, Davis California.
proceedings of the Second International Drip Irrigation Congress, pp. 416-421,
july 1974. 3 fig, 9 ref.
Descriptors: *Fertilization, *Fertilizer, *Phosphorus, Irrigation practices,
Irrigation systems, Irrigation, Agriculture.
There is little doubt after 60 years of scientific investigation with several
sources of inorganic phosphate that phosphorus moves very little from point of
contact with the soil. The greatest successes in measuring increased movement
of phosphorus in the soil profile have occurred with organic forms of phosphorus.
The development of new cultural management techniques such as trickle irrigation
'make the use of a water-soluble, non-corrosive, high analysis source of organic
phosphorus an especially desirous material. A material with this capability
would be of great value where trickle systems make it extremely difficult to
achieve placement by mechanically injecting phosphorus below the soil surface.
The movement and sorption of glycerol phosphate was studied in unsaturated
soil columns during steady-state displacement of a fertilizer pulse. Fertilizer
pulses equivalent to 90 kg/ha application rates were displaced at flow rates
Between 5 and 15 cm/day. Results demonstrate that glycerol phosphate is capable
Of being displaced to much greater depths than inorganic forms of phosphorus
fertilizer. It is expected that glycerol phosphate can be applied through a
trickle irrigation system and be distributed within the wetted root zone.
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74:03F-072
SOIL MOISTURE DISTRIBUTION AND WETTING PATTERN FROM A POINT SOURCE,
Roth, R.L.
Arizona University, Yuma, Arizona.
Proceedings of the Second international Drip irrigation congress, pp. 246-251,
July 1974. 4 fig.
Descriptors: *Wetting, *Water levels, *Flow rates, *Soil water, Irrigation,
Irrigation systems, Agriculture.
Soil moisture distribution and wetting pattern tests were conducted using a
point source on virgin desert sandy soil. The purpose of these studies was to
characterize the extent of moisture movement and distribution within the wetted
volume. The flow rates tested were approximately 3-8, 7.6, and 15.2 liters
per hour (1, 2, and 4 gph) for durations of 1, 3, 6, 12, 24, and 48 hours. At
the completion of each test, a pit was dug which exposed the maximum vertical
diametral plane of the wetted volume. Measurements were made to define the
maximum wetted area. Soil moisture measurements were made at each node point
of a 15.2-centimeter (6-inch) grid imposed on the maximum wetted area. Soil
cores were taken at 15.2-centimeter intervals along the line of maximum
horizontal water movement. These cores were used to determine bulk density,
soil texture, permeability, and moisture release characteristics. A complete
sail profile description was also made of each test site. For the tests
conducted the total volume of soil wetted was more a function of the amount of
water applied than time of application. Maximum horizontal movement was greater
than maximum vertical movement for volumes of water less than 190 liters
(50 gallons). Greater maximum vertical movement occurred at volumes of water
more than 190 liters. Water within the wetted volume was determined to be at
tensions between 100-140 centimeters of water.
74:03F-073
COMPARISON OF IRRIGATION METHODS, ROOTSTOCKS, AND FERTILIZER ELEMENTS ON
VALENCIA ORANGE TREES,
Roth, R.L., Rodney, D.R., and Gardner, B.R.
Arizona University, Yuma, Arizona.
Proceedings of the Second International Drip Irrigation Congress, pp. 103-108,
July 1974.
Descriptors: *Sprinkler irrigation, *Surface irrigation, *0ranges, *Fertili-
zation, *Fertilizers, Saline water Saline soil, Irrigation practices,
Irrigation systems. Irrigation, Agriculture.
A 4-hectare (10-acre) block of 'Campbell1 Valencia orange trees planted in May
1971, was used to compare 5 irrigation methods, 2 types of rootstocks, and a
phosphate and micronutrient variable. The irrigation methods were border, full-
coverage sprinklers, limited-coverage sprinklers, basin, and trickle. Maximum
tree growth, as measured by increase in trunk circumference, was achieved from
the trickle and basin irrigation methods, even though these methods used
approximately one-twentieth the water as compared to the normal border irrigation
method. The full-coverage sprinkler method restricted tree growth due to salt
injury of the leaves. Nitrate and salt concentrations in the root zone were
mapped for each irrigation method. No observable effects of the fertilizer
variables have been detected at this time.
74:03F-074
THE USE OF FOGGERS IN DRIP IRRIGATION,
Schade, R.o.
Perma Rain Irrigation, Inc., Lindsay, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 129-130.
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July 1974.
Descriptors: Crop response, Irrigation systems, Irrigation practices,
Irrigation, Agriculture.
The rapid increase in drip irrigation in the United States has been accompanied
by a large number of new products for its application. Most of this new
equipment has been emitters of various types. These emitters are used to
reduce the flow and to apply the water directly to the surface of the soil. In
addition to emitters a device known as a fogger is also being widely used. The
fogger as the name implies fogs or sprays the water into the air. The droplet
size and output of each fogger ranges from 2 to 5 gallons per hour which is
comparable to discharge rate of most emitters being used today. Foggers have
been installed on an estimated 8,000 acres. This accounts for approximately
15% of the acreage being irrigated by drip irrigation. Foggers are being used
to irrigate citrus, decidious fruit, grapes, nuts and ornamentals. The area
of principal usage at the present time is in the San Joaquin Valley of
California.
74:03F-075
TRICKLE IRRIGATION,
Shani, M.
Irrigation and Soil Field Service, Tel-Aviv, Israel.
proceedings of the Second International Drip Irrigation Congress, pp. 91-96,
july 1974.
Descriptors: Filtration, Fertilization, Irrigation systems, Irrigation
practices. Irrigation, Agriculture.
Article presents advantages and disadvantages of trickle irrigation, types of
emitters, filtration methods, and a discussion of fertilization techniques
based on experience in Israel.
74:03F-076
PRIP IRRIGATION RESEARCH IN OREGON - A PROGRESS REPORT,
Shearer, M.N., Martin, L.W., Lombard, P.B., and Mellentin, W.M.
Oregon State University, Corvallis, Oregon.
proceedings of the Second International Drip Irrigation Congress, pp.38-43,
July 1974. 4 fig, 3 tab.
Descriptors: Crop response, Crop production, Sugarcane, Oregon, Irrigation
system, Irrigation, Agriculture, Sprinkler irrigation, Filtration.
Drip irrigation research was initiated in Oregon in 1973. One year's results
are reported on the following: (1) total yield, fruit size, water requirements,
and mold incidence of cane fruit under drip and sprinkler irrigation, (2) total
yield, fruit aize, and water requirements of pears grown on low intake rate
montmorillonite soils under drip and rill irrigation, (3) evaporation pan
coefficients for scheduling drip irrigation, and (4) filtering requirements for
irrigation water containing glacial silt and flour.
74-03F-077
DRIP VS. FURROW IRRIGATION TRIALS IN POTATO UNDER SUBTROPICAL CONDITIONS,
Singh, N.T., Grewal, S.S., and Josan, A.S.
Punjab Agricultural University, Ludhiana, India.
proceedings of the Second International Drip Irrigation Congress, pp. 515-520,
july 1974. 1 fig, 2 tab, 17 ref.
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Descriptors: *Potatoes, *Crop response, *Soil temperature, *Subtropic,
Furrow irrigation, Irrigation systems, Irrigation practices, Irrigation,
Agriculture.
The drip method of irrigation was compared with conventional furrow irrigation
in field grown spring and autumn potatoes. Treatments included irrigations at
0.25, 0.50, and 0.75 bar soil moisture tension at 10 cm depth and drip
irrigation. As an average of six crops, for equal amounts of water used drip
irrigation gave 60 q/ha or 31% higher yield than irrigation at 0.25 bar soil
moisture tension. Irrigation at 0.50 and 0.75 bar tension yielded significantly
lower than these treatments. Wetter soil moisture regimes lowered the maximum
soil temperature at 10 cm depth by 1 to 3.5°C thereby bringing it closer to the
optimum required by the crop. Effect of soil moisture on soil temperature and
soil strength was isolated using organic mulches. Soil temperature appeared to
be a critical factor in improving yield and quality of potatoes. Drip
irrigation promises a more suitable soil moisture and soil temperature regime
for potato cultivation in the subtropics.
74:03F-078
EDAPHIC MICRO-TUBULAR CONTINUOUS FLOW IRRIGATION IN CANADA,
Stevenson, D.S. and Tait, R.S.
Canadian Department of Agriculture, Summerland, B.C.
Proceedings of the Second International Drip Irrigation Congress, pp. 86-90,
July 1974. 3 fig, 4 tab.
Descriptors: Soil water movement, Canada, Irrigation systems. Irrigation,
Agriculture.
A soil's ability to transfer water horizontally relative to vertical drainage is
its most important characteristic in trickle irrigation. Water applied to a
soil at a single point will move laterally and vertically. The shape of the
resulting half sphere will depend upon the ratio of saturated conductivity to
unsaturated conductivity of any particular soil. The limit to horizontal
movement before drainage becomes excessive determines that area that we can
expect to irrigate with one dripper. Rooting depth of the crop imposes a
limit to the area over which water will spread before an excess of it becomes
drainage. Evapotranspiration (ET) over the area so defined thus determines the
continuous flow from the dripper. Areas and ET are easily equated to provide
dripper flows in g.p.h. The areas provide the dripper spacing for uniform
irrigation. Micro-tubing of varying sizes and lengths as emitters provides
flow control at the emitters for both level and sloping land. Seasonal
changes in irrigation requirements (ET) are satisfied by alterations in line
pressures as needed.
74:03F-079
MOISTURE PROFILES AMD SALINIZATION OF SOILS UNDER DRIP IRRIGATION IN THE
REPUBLIC OF SOUTH AFRICA,
Streutker, A.
Department of Agricultural Technical Services, Pretoria, South Africa.
Proceedings of the Second International Drip Irrigation Congress, pp. 258-263,
July 1974. 4 tab.
Descriptors: *Saline soil, *Moisture content, *Crop production, *Flow rates,
*Cotton, *Potatoes, *Tomatoes, Irrigation practices, Irrigation systems.
Irrigation, Agriculture.
Soil moisture profiles, salinization of soils, water use, and production of
cotton, potatoes and tomatoes are measured on experimental plots on four soils,
from sand to clay, with three different dripper spacings, and three different
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drip intensities. Simultaneously, soil moisture profiles and salinization are
measured on different soils under citrus-trees, peach-trees and vineyards with
commercial drip irrigation systems under different climates.
74:03F-080
AFFORESTATION WITH SALINE WATER IN ABU DHABI,
Tahnoon, S. and Aljibury, F.K.
Minister of Agriculture, Abu Dhabi.
Proceedings of the Second International Drip Irrigation Congress, pp. 370-371,
July 1974.
Descriptors: *Forestry, *Saline water, Irrigation systems, Irrigation,
Agriculture.
The government of the country of Abu Dhabi is trying to make the desert bloom
under adverse soil, wind, and water conditions.
74:03F-081
EFFECTS OF LOCALIZED PHOSPHATE TREATMENTS AND SOLUTION pH ON THE GROWTH AND
FUNCTION OF APPLE ROOTS,
Taylor, B.K. and Goubran, F.G.
Scoresby Horticultural Research Station, Ferntree Gully, Australia.
proceedings of the Second International Drip Irrigation Congress, pp. 395-399,
July 1974. 4 tab.
Descriptors: *Phosphates, *Crop response, *Apples, *Root development, Nutrients,
Irrigation systems, Irrigation, Agriculture.
Following the introduction of trickle irrigation to orchards, interest has
risen in the possibility of feeding nutrients into such systems on a regular
basis* Use of phosphatic fertilizer in this way, however, could pose a
problem in that a highly localized source of P would be available to only a
small portion of the root system of the tree. Movement of P away from the
trickle outlet would be restricted in most orchard soils by fixation processes.
•jjie influence of localized applications of phosphate on the growth and function
of apple roots at two pH levels is reported.
74:03F-082
SOME RESULTS OF A FIELD SURVEY OF DRIP IRRIGATION SYSTEMS IN THE REPUBLIC OF
SOUTH AFRICA,
Uys, W.J.
Department of Agricultural Technical Services, Pretoria, South Africa.
proceedings of the Second International Drip Irrigation Congress, pp. 65-70,
July 1974. 4 tab.
Descriptors: *Clogging, Flow rates, *Surveys, Irrigation, Irrigation systems,
Agriculture.
^n extensive survey was conducted in the Republic of South Africa on existing
driP irrigation systems to evaluate drip irrigation systems under a variety of
climatic, soil, crop and management conditions. The purpose of the survey is
to identify specific problems of practical farming conditions and to identify
specific problems of design, operation, and management from which future
extension and research programs can be formulated.
74:03F-083
DISINFECTION OF SOIL STRIPS THROUGH THE DRIP IRRIGATION SYSTEM,
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uzrad, M. and Goldberg, S.D.
The Hebrew University of Jerusalem, Rehovat, Israel.
Proceedings of the Second International Drip Irrigation Congress, pp. 137-141,
July 1974. 3 tab.
Descriptors: *Disinfection, Management, Crop production, Irrigation systems,
Irrigation, Agriculture.
Seasonal crops (vegetables) are often grown on a limited area in the Arava
agricultural plots thus causing contamination. Manure of unknown origin
increases the rate of contamination. After several seasons of cultivation,
there is a marked decrease in the level of the agricultural production. It is
customary to disinfect soils by means of methyl bromide. Row crops in the
Arava desert are irrigated by the drip system, thus the cultivation,
fertilization, and irrigation is restricted to the cultivated strip. An
experiment was conducted to apply the disinfectant only to the cultivated strip
through the drip system. Hot gaseous methyl bromide was applied through the
drip laterals and through the drippers which were covered by plastic mulch.
The treated areas yielded crops three times higher than in the control plot.
74:03F-084
HYDRAULICS OF SINGLE-CHAMBER VS. DUAL-CHAMBER TUBING,
Vaziri, c.M.
Hawaiian Agronomics, Inc., Honolulu, Hawaii.
Proceedings of the Second International Drip Irrigation Congress, pp. 293-298,
Julyl974. 2 tab.
Descriptors: *Hydraulic design, *Hydraulic properties, *Hydraulics, *Irrigation
design. Irrigation, system, Irrigation, Agriculture.
The basic hydraulic relationship of pressure, orifice diameter, coefficient
of discharge, and the friction loss along a tube is a necessity before one can
design an adequate drip or subsurface irrigation system. There are several
types of tubing and emitters available. But the most unique difference
hydraulically is the single chamber tubing versus a dual chamber tubing. The
single chamber tube is found to provide an acceptable range of orifice flow
uniformity from the head of tubing to the end for approximately 300' of length.
Beyond this reach the friction loss in the 1/2" polyethylene tubing is excessive
and causes a reduction in the orifice flow rate. The flow rate through each
plastic orifice is proportional to the square root of the pressure inside the
tubing at the orifice point. The other type of tubing that has been experimented
with is dual chamber tubing. One chamber is for the conveyance. This in turn
is connected to the outside chamber (the distribution tube) and water is emitted
to the outside through desired orifice spacing, depending on soil types and
plantings. Equations are developed to describe the flow pattern for dual
chamber tubing and the relationship between the inner and outer chamber. The
effect of orifice diameters and orifice spacing on the outer chamber pressure is
discussed.
74:03F-085
LINEARIZED MOISTURE FLOW SOLUTIONS FOR POINT, LINE, AND STRIP SOURCES,
Warrick, A.W. and Lomen, D.O.
Arizona University, Tucson, Arizona.
Proceedings of the Second International Drip Irrigation Congress, pp. 228-233,
July 1974. 3 fig, 1 tab, 12 ref.
Descriptors: *Soil water movement. Mathematical studies. Irrigation system,
Irrigation, Agriculture.
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Solutions and numerical results are given for the time-dependent, linearized
moisture flow equation for point, line, and strip sources. The linear form is
attained by assuming an unsaturated hydraulic conductivity of the form K » ko
exp (alpha h) with KQ and alpha constants and with h the pressure head. In
addition, the derivative of K with respect to the volumetric water content is
taken as a constant. Numerical results include? (1) spatial distribution of the
matric flux potential for 6 times including a comparison of 2 flow rates for a
point source; (2) pressure head distribution near a single point source under
cyclic conditions; (3) pressure head distribution for 2 point sources under
cyclic conditions, and (4) moisture distribution patterns near line and strip
sources. The major advantage of using the linearized forms is that solutions
for simplified geometries may be superimposed both in time and space to simulate
complex geometries and inputs of water. The major disadvantage of the non-
linear nature of the soil-hydraulic functions is lost. For cyclic moisture
regimes at a high frequency, it is assumed the water content fluctuation of any
point will be relatively small and the linearizing assumptions are realistic.
74:03F-086
MOBILE DRIP IRRIGATION SYSTEMS,
Wilke, O.C.
Texas Agricultural Experiment Station, Lubbock, Texas.
proceedings of the Second International Drip Irrigation Congress, pp. 188-192,
July 1974. 5 fig.
Descriptors: Irrigation design, Irrigation operation and maintenance, Irrigation
practices. Irrigation, Agriculture.
A tractor-mounted device for moving drip irrigation laterals is described.
Time periods required to load, move and unload laterals are presented. Several
drip irrigation trail lines were attached to a pivot sprinkler system. The
design and performance of the system are discussed.
74:03F-087
SEED GERMINATION RESPONSE TO SUBSURFACE IRRIGATION DEPTH,
Willardson, L.S.
Agricultural Research Service, Brawley, California.
proceedings of the Second International Drip Irrigation Congress, pp. 178-182,
July 1974. 4 fig, 2 ref.
Descriptors: *Subsurface irrigation, *Cotton, *Alfalfa, *Germination, Crop
response, Irrigation practices, Irrigation, Agriculture.
A line source subsurface irrigation system was installed at 0, 2.54, 5.08, 10.16,
and 20.32 cm depths in a sandy silt soil. The E.G. of the soil varied between
10.4 and 16.2 mmhos per cm. Cotton and alfalfa were used to determine the effect
of depth of placement of the seeds and water source on germination.
74:03F-088
CANTALOUPE RESPONSE TO DRIP IRRIGATION,
Willardson, L.S., Bohn, G.W., and Huber, M.J.
Agriculture Research Service, Brawley, California.
proceedings of the Second International Drip Irrigation Congress, pp. 474-479,
July 1974. 3 tab.
Descriptors: *Root distribution, *Crop response, *Furrow irrigation, Irrigation
systems, Irrigation practices, Irrigation, Agriculture.
Changes in rooting pattern may change nutrition and plant response, and thus
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alter desirable characteristics of plants. Five experiments conducted included
nine cantaloupe cultivars grown on silty clay loam with drip and furrow
irrigation systems. The different irrigation management practices followed
have resulted in variable plant responses.
74:03F-089
CONTROL OF WATER BY DRIP IRRIGATION FOR ALFALFA SEED PRODUCTION,
Willardson, L.S., Hageman, R., and Marsh, A.W.
Agriculture Research Service , Brawley, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 172-177,
July 1974. 2 tab, 3 fig.
Descriptors: *Alfalfa, *Seeds, Crop response, Irrigation systems, Irrigation
practices, Irrigation, Agriculture.
Drip irrigation controlled soil water tension treatments in an alfalfa seed
production experiment resulted in a 4-fold yield difference between the best
and poorest treatments. The experiment had 6 replications of 4 treatments and
has been conducted for 2 years. Yield of forage as well as seed yields were
determined.
74:03F-090
SALINITY SENSOR CONTROL OF DRIP IRRIGATION WATER APPLICATION,
Willardson, L.S. and Oster, J.D.
Agriculture Research Service, Brawley, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 335-340,
July 1974. 3 fig, 1 tab, 1 ref.
Descriptors: *Salinity, *Saline soil, Crop response, Irrigation practices,
Irrigation systems, Irrigation, Agriculture.
In-situ salinity sensors were used to control water application by drip
irrigation to maintain a constant soil salinity. Milo was grown on small field
plots instrumented with salinity sensors to evaluate the effect of depth of
placement and initial soil salinity on plant growth and water control. Water
application was fully controlled by the sensors. Response time was short
enough to encourage practical use.
74:03F-091
AN INVESTIGATION INTO THE POTENTIAL USES OF TRICKLE IRRIGATION FOR DESERT
RECLAMATION AND FODDER PRODUCTION IN THE EMIRATE OF ABU DHABI,
Willens, A.F. and Willens, G.A.
Agricultural Planning Associates, Ltd. London, England.
Proceedings of the Second International Drip Irrigation Congress, pp. 288-293,
July 1974. 4 tab, 4 ref.
Descriptors: Crop response, Land reclamation. Deserts, Irrigation systems.
Irrigation, Agriculture.
An initial investigation into the possible uses of trickle irrigation to
establish a range of plant species which could be potentially useful as
fodder is described. The use of trickle irrigation for fodder tree production
shows considerable potential and appears economically viable within the
present social context of Abu Dhabi.
74:03F-092
CHANGES IN ROOT PATTERNS OF PEACH TREES UNDER TRICKLE IRRIGATION,
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P. and Cockroft, B.
Department of Agriculture, Victoria, Australia.
Proceedings of the Second International Drip Irrigation Congress, pp. 439-442,
July 1974. 3 tab.
Descriptors: *Peaches, *Root development, *Root distribution, *Root systems,
Crop response, Irrigation effects, Irrigation systems, Irrigation, Agriculture.
With fully mature peach trees, which before the installation of a trickle system
had a uniformly distributed root system through the whole orchard area, the
change to trickle produced a remarkable adaption by the tree. A whole new root
system was developed in a few months, and the trees continued to produce heavy
crops of fruit.
74:03F-093
USE OP DRIP IRRIGATION IN GERMANY,
Wolff, P.
Kassel University, Germany.
Proceedings of the Second International Drip Irrigation Congress, pp. 71-76,
July 1974.
Descriptors: Sprinkler irrigation. Irrigation systems, Irrigation, Agriculture.
Irrigation methods similar to drip irrigation have been used in Germany for
many years, and more horticulturalists are changing from overhead irrigation to
drip irrigation. The reasons for changing irrigation methods were investigated
by the author and his coworkers. It was found that the horticulturalists are
changing methods because of increasing labor costs and an increasing demand for
high quality products.
74:03F-094
DRIP IRRIGATION IN CITRUS ORCHARDS,
Yagev, E. and Choresh, Y.
Ministry of Agriculture, Israel.
proceedings of the Second International Drip Irrigation Congress, pp. 456-461,
July 1974. 2 fig, 7 tab.
Descriptors: *Oranges, *Crop response, Root development. Salinity, Saline soil,
irrigation systems. Irrigation, Agriculture.
in a Valencia orange grove grafted onto sour orange root stock, drip irrigation
treatments of one and two laterals per row of trees at semi-weekly and bi-
weekly intervals was compared to the standard treatment of sprinkler irrigation.
The water application to all treatments was based on identical daily rates.
The factors checked were salt accumulation and moisture distribution pattern in
the soil profile, root development, mineral content of leaves, weight of yield
and number of fruit per tree, and fruit quality. There was no difference in
yield and fruit quality between the treatments checked. The average salt
accumulation in the soil was less with the drip irrigation treatments than with
the sprinkler irrigation. The soil moisture tension below the drip lateral
was low all the time and there is reason to believe that there is a loss of water
below the root zone. There was no significant difference in root development
between all the treatments.
74:03F~095
STEADY INFILTRATION FROM LINE SOURCES BURIED IN SOIL,
Thomas, A.W., Kruse, E.G., and Duke, H.R.
United States Department of Agriculture, Watkinsville, Georgia.
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Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 1,
p 125-129 & 133, January-February 1974. 7 fig, 6 ref.
Descriptors: *Soil water movement, *Subsurface irrigation, *Infiltration,
*Mathematical studies, Mathematical modeling, Irrigation systems, Irrigation,
Agriculture.
Paper presents the results of a study of steady infiltration from a distribution
of buried line sources which lie in a horizontal plane and are parallel and
equally spaced. The sources simulate subsurface irrigation laterals. An
analytical solution is made possible by the use of a quasilinear form of the
differential flux equation and an exponential relationship between hydraulic
conductivity and capillary potential of the soil modeled. The objective of the
paper is to develop the analytical solution and compare the computed distribu-
tions of capillary potential for normal field lateral spacings and depths with
those computed by more complex methods.
74:03F-096
HIGH RATE SPRINKLING OF A LOW INTAKE SOIL,
Willardson, L.S., Ertsgaard, B.L., Ehlig, C.F., and MacKenzie, A.J.
United States Department of Agriculture, Brawley, California.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
p 280-281, March-April 1974. 2 fig, 1 tab.
Descriptors: *Sprinkler irrigation, Irrigation practices. Irrigation operation
and management. Irrigation effects, Frequency, Puddling, Soil management,
Soil properties, Irrigation, Agriculture.
Water can be applied to low intake rate soils by sprinkling at high average
application rates if water is applied intermittently and the average application
rate does not exceed the average instantaneous intake rate during the interval
of operation. Soil crusts formed on the soil surface when the soil dried, but
these crusts did not interfere with plant growth. Greater total amounts of
water can be applied without causing ponding and loss of soil surface structure
by the use of short sprinkling intervals and by applying smaller amounts of
water per day. For equal amounts of applied water, short duration - high
frequency applications caused less loss of soil surface structure than long
duration - low frequency applications.
74:03F-097
CHAMBER METHOD OF SUBSURFACE AND DRIP IRRIGATION,
Pira, E.S. and Purohit, K.S.
Massachusetts University, Amherst, Food and Agricultural Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
P282-285, March-April 1974. 6 fig, 18 ref.
Descriptors:*Design criteria, *Irrigation design, *Subsurface irrigation, *Head
loss, Irrigation methods, Flow rates, Irrigation, Agriculture.
By varying cross sectional area and length of the low pressure distribution
line (chamber), uniform discharge rates can be produced through emitters.
Discharge rates can be changed by adjusting chamber pressure. "Quick-fill" is
necessary to make the system practical. In other words, the chamber must be
charged with water before good operation begins. Field installation in an
apple orchard is discussed.
74:03F-098
ALTERNATE-FURROW IRRIGATION OF FINE TEXTURED SOILS,
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Musick, J.T. and Dusek, D.A.
United States Department of Agriculture, Bushland, Texas, Southwestern Great
Plains Research Center.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
p 289-294, March-April 1974. 10 fig, 1 tab, 8 ref.
Descriptors: *Furrow irrigation, *Purrow systems. Irrigation effects. Irrigation
efficiency. Irrigation practices, Furrows, Crop response, Sugarbeets, Grain
sorghum, Potatoes, Soil salinity, Infiltration rates, Irrigation, Agriculture.
Alternate-furrow irrigation of bed-furrow spacings ranging from 30 to 40 inches
were evaluated for irrigating slowly permeable Pullman soils. Alternate-
furrow irrigation had little effect on water intake and yields on Pullman silty
clay loam but significantly reduced both intake and yields of sugarbeets and
grain sorghum on Pullman clay loam. The reduction in water intake and yields
was concentrated on the lower one-fourth to one-half of the field plots
depending primarily on the irrigated furrow spacing and length of run. Lateral
wetting extended from the irrigated furrow into the adjacent nonirrigated
furrow past midfield under all conditions evaluated. Alternate-furrow irrigation
of bed-furrow spacings exceeding 30 inches is not recommended on slowly
permeable clay loam soils. Although alternate furrow irrigation significantly
reduced the size of irrigation, the concentration of this effect on the lower
part of a field and associated yield reductions limits the usefulness of the
practice for more efficient management and use of water.
74:03F-099
IRRIGATION TIMING BY THE STRESS DAY INDEX METHOD,
Hiler, E.A., Howell, T.A.,' Lewis, R.B., and Boos, R.P.
Texas A&M University, College Station, Agricultural Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 3,
p 393-398, May-June 1974. 2 fig, 8 tab, 28 ref.
Descriptors: *Stress, *Stress analysis. Irrigation practices, Crop production.
Optimization, Water conservation, Water requirements, Irrigation, Agriculture.
A potentially useful concept for optimizing irrigation timing is the stress day
index (SDI). The purposes of this paper are to briefly define SDI and its
components, to illustrate through examples how this approach can be utilized
for timing irrigations, and to present experimental findings related to use of
SDI. The S°I concept is formulated as the product of a crop susceptibility
factor (CS) and a stress day factor (SD). Values of CS depend on species
and stage of development and indicate the plant's susceptibility to a given
water deficit at different growth stages. A method for determining CS is given
along with quantitative values for various irrigated crops. Irrigation timing
is accomplished with the SDI approach by irrigating when the daily SDI (daily
SD x CS for the appropriate growth stage) reaches some predetermined critical
value. Basically, the water deficit indicator(SD) is weighted according to
crop sensitivities at different growth stages so that reduced water deficit
occurs during critical periods.
74:03F-100
WATERHAMMER CONSIDERATIONS FOR PVC PIPELINE IN IRRIGATION SYSTEMS,
Seipt» W.R.
certain-teed-Products Corporation, Valley Forge, Pennsylvania.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 3,
p 417-423, May-June 1974. 6 fig, 5 tab, 26 ref.
Descriptors: *Waterhammer, Hydraulic conduits. Hydraulic design, Hydraulic
equipment, Hydraulic structures, Irrigation design, Flow Characteristics,
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Agriculture, Irrigation.
Waterhammer pressure develops whenever flow is changed. Flow changes occur by
operating valves, by starting or stopping pumps, or by sudden release of
entrapped air. Its intensity depends upon the rate of change. On occasion, it
damages piping. Waterhammer can be contained by: adequate design; proper
installation and responsible use.
74:03F-101
EVERY-O1HER FURROW IRRIGATION OF CORN,
Fischbach, P.E. and Mulliner, H.R.
Nebraska University, Lincoln, Agricultural Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 3,
p 426-428, May-June 1974. 4 tab, 9 ref.
Descriptors: *Irrigation practices. Irrigation effects. Irrigation efficiency,
Corn, Furrow irrigation, Surface irrigation, Irrigation, Agriculture.
Every-other furrow irrigation was compared with every furrow irrigation on
several soil types in Nebraska under various rainfall conditions. Analysis
of the data shows no significant differences at the 5 percent level in corn
grain yields on any soil texture when comparing every-other furrow with every
furrow irrigation using 2 1/3 to 12-hr, irrigation sets. Further analysis of
the data shows that the irrigation water moves laterally from the irrigated
furrow to the adjacent dry furrow to a depth of 3 feet even with a 2 1/3-hr.
irrigation set. Therefore, both manually and automated irrigation systems can
be designed for every-other furrow irrigation.
74:03F-102
DRIP IRRIGATION DESIGN BASED ON UNIFORMITY,
Wu, and Gitlin, H.M.
Hawaii University, Honolulu, Department of Agricultural Engineering.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 3,
p 429-432, May-June 1974. 4 fig, 5 ref.
Descriptors: *Uniformity coefficient, Irrigation design. Irrigation systems,
Irrigation, Agriculture.
The paper presents a general shape of the energy gradient line which can be
applied to estimate distribution and variation of emitter discharge along the
lateral. A design chart is presented for determining an acceptable combination
of lateral lengths and inlet pressure of a drip irrigation system. The chart
helps in selecting a drip irrigation line based on a desirable or acceptable
uniformity coefficient. The designer can try different combinations
and length in order to obtain a design which is acceptable.
74:03F-103
SPRINKLER IRRIGATION DESIGN CRITERIA FOR SUGAR BEETS,
Finken, D.W., Steele, J.C., and Fischbach, P.E.
Nebraska University, Scottsbluff, District Extension Irrigation Engineer,
Panhandle station.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 5,
p 889-891, September-October 1974. 5 tab, 7 ref.
Descriptors: *Sprinkler irrigation, *Irrigation design. Irrigation practices.
Design criteria, Sugarbeets, Consumptive use, Nebraska, Crop response.
A solid set sprinkler system was used to simulate center pivot sprinklers in a
search for the smallest design capacity which would not reduce yields of
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irrigated sugar beets. The peak daily consumptive use of sugar beets in
western Nebraska is about 0.33 in. per day. A system with the capacity to
supply this amount to the crop would need a capacity in excess of 0.33 in. per
day to allow for water losses. The results indicate that systems that can
apply 0.20 in per day, without allowing for water losses, are sufficient to
produce sugar beets in western Nebraska without incurring a reduction in yield.
74:03F-104
TRICKLE IRRIGATION LATERAL DESIGN,
Howe11, T.A. and Hiler E.A.
Texas A&M University, College Station, Agricultural Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 5,
p 902-907, September-October 1974. 5 fig, 2 tab.
Descriptors: *Irrigation design, *Hydraulics design, *Hydraulic properties,
*Computer programs. Irrigation systems, irrigation, Agriculture, Design.
A design method for determining the pressure loss and emitter flow ratio for
trickle irrigation laterals is presented. The design method is based upon
known principles of fluid mechanics. A computer program was written to
determine the lateral pressure loss and emitter flow ratio at a given design
length as a fuction of pipe size, tree spacing, number of emitters per tree,
emitter spacing, downstream lateral pressure, and lateral slope. For a given
set of design inputs, the program can be used to determine if the given pipe
size will be adequate to limit the pressure loss and flow variation along the
lateral to limits acceptable for the design lateral length.
74:03F-105
THE EFFECT OF SOIL WATER SUPPLY ON CORN FERTILIZER RESPONSE,
Olson, T.C. and Onstad, C.A.
United States Department of Agriculture, Agricultural Research Service, Morris,
Minnesota.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 5,
p 914-916, September-October 1974. 5 tab, 10 ref.
Descriptors: *crop response, *corn, *Soil water, *Fertilization, Rainfall, Crop
production, Statistics, Agriculture, Agronomic crops. Moisture stress, Moisture
availability, Moisture content.
The study reported was designed to determine the possibility of estimating the
optimum amount of fertilizer needed for greatest efficiency when the amount of
water stored in the soil profile at planting time is known. Conversely, would
increasing stored water increase the efficiency of fertilizer? Responses to
applied fertilizer under different levels of stored water at planting and
different patterns of rainfall were studied to identify the types of interactions
between water stress and fertility response by corn. Corn grain yields for six
treatments are reported for each year. Significant differences as indicated by
LSD are shown on an individual year basis. Annual average yields of main
treatments illustrate the influence of stored water. The combined analysis of
varience indicated highly significant differences in yield among years but no
significant difference in overall average yields among main treatments or be-
tween fertility levels. The year x main treatment, and the year x fertility-
level interactions were both highly significant (p= 0.01) and the main-treatment
x fertility level x year interaction was significant at the 0.05 level.
74:03F-106
TRICKLE IRRIGATION DESIGN PARAMETERS,
Keller, J. and Karmelli, D.
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Utah State University, Logan, Agricultural and irrigation Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 4,
p 678-684, July-August 1974. 4 fig, 1 tab, 12 ref.
Descriptors: *Design criteria, *Irrigation design. Design flow. Flow character-
istics. Irrigation, Agriculture.
Paper consists of basic definition, objectives of trickle, advantages and
disadvantages. Formulas for computation of irrigation depth and interval, flow
rates through emitters, system capacity, flow characteristics of various
emitters, and emission uniformity (EU) are all presented. Lateral and manifold
design are presented along with an example of system layout with complete
design figures.
74:03F-107
INSTALLATION CHECKS ON 4-INCH (102 MM) CORRUGATED POLYETHYLENE DRAIN TUBING,
McCandless, D.E., Jr.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 8 tab, 3 ref.
Descriptors: *Plastic pipes, Pipelines, Construction, Drainage, Drainage
engineering, Drainage practices.
Results of 54 installation checks on a 4-inch (102 mm) corrugated polyethylene
drain tubing in 4 Northeastern states are reported. Checks were made by Soil
Conservation Service personnel with the assistance of farmers, contractors,
and manufacturers' representatives, Tubing installed in gravel soil sites
generally had deflections 2 to 5 percent higher than those in clay or sandy
soils. Tubing installed in sandy soils had the least deflection and commonly
ranged from 13 to 20 percent. Tubing installed in trenches 4 to 5 feet (1.2 to
5 m) deep in sandy soils was doing as well or better than tubing installed at
lesser depths. Subsurface drains in the Northeast are commonly installed in
trenches 2 1/2 to 4 feet (0.8 to 1.2 m) deep. With 14 percent of the sites
being classified as unsatisfactory, it is obvious that in many areas of the
Northeast there is a need for a training and i stallation program on good
installation procedures for SCS personnel, contractors, and farmers.
74:03F-108
ELONGATION CHARACTERISTICS OF CORRUGATED PLASTIC TUBING,
Schwab, G.O. and Brehm, R.D.
Ohio State University, Columbus.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 5 fig, 6 ref.
Descriptors: *Plastic pipes. Plastic deformation, Temperature, Pipelines,
Construction.
Elongation (stretch) of circular corrugated plastic tubing decreased parallel
plate stiffness at 5% deflection about 1.6%, 2.3%, and 0.4% for each one
percent elongation of 76 mm (3-in), 102 mm (4-in), and 152 nun (6-in) diameter
tubing, respectively. Four brands of tubing were included in the tests. Stiff-
ness of 203 mm (8-in) diameter tubing consistently (4 brands) increased up to
5% elongation with only a small decrease at 10%. In other tests the elongation
of three brands of 102 mm tubing varied from about 2 to 6% at 23°C (standard
test temperature) and from 9 to 18% at 70°c. For all three brands tested,
elongation varied linearly with temperature. Spiral corrugations showed less
elongation than circular corrugated tubing. Elongation of corrugated tubing
in the field as installed with several trenching machines varied from zero to
4.5% with an average of 2.1%. Although tubing temperature was high (35 to 52°C),
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temperature did not appear to be a major cause of stretching. Frictional drag
and other effects as the tubing passed through the machine caused most of the
stretching. The study showed that elongation is not a serious (up to 5%)
problem unless the contractor is careless of intentionally stretches the tubing.
74:03F-109
FUNDAMENTALS OF PROGRAMMED SOIL MOISTURE DEPLETION,
Fonken, D.W. and Fischbach, P.E.
Nebraska University, Panhandle Station, Scottsbluff.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 4 fig, 11 ref.
Descriptors: *Scheduling, Soil moisture, Water utilization. Irrigation,
Irrigation practices. Irrigation operation and management, Energy.
Programmed soil moisture depletion is an irrigation scheduling policy for
achieving improved water use efficiency and energy savings. It requires
medium or fine textured soils, irrigation hardware that can apply small
controlled amounts of water, a climate and/or irrigation supply which can
provide off-season rainfall and irrigation, and a relatively high level of
irrigation management. It is recommended as a technique to reduce peak season
irrigation requirements by utilizing previously wasted rainfall and off-season
irrigation capability.
74s03F-110
ANHYDROUS AMMONIA APPLICATION IN IRRIGATION WATER VS. MECHANICAL AND ITS EFFECT
ON CORN YIELDS,
Mulliner, H.R. and Frand, K.D.
Nebraska University, South Central Station, Clay Center, Department of
Agricultural Engineering.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 4 tab.
Descriptors: *Nitrogen, *Nitrogen .compounds, *Corn, Fertilization, Fertilizers,
irrigation practices. Irrigation water. Irrigation.
Application of anhydrous ammonia in surface irrigation distribution systems
requires top level management. From an energy standpoint, it is more effective
because optimum yields can usually be obtained with less nitrogen, and the
energy for mechanical application is saved. In the manufacturing process,
energy is required to convert anhydrous ammonia to ammonium nitrate and urea;
thus* the ability to utilize anhydrous ammonia directly in surface irrigation
systems is an additional savings of energy. Salts in the irrigation water
presented no problem of encrusting inside the distribution system (aluminum
gated pipe) when the inhibitor sodium polyphosphate was used. Irrigation
water will carry from 50 to 110 ppm anhydrous ammonia before it is lost into
the atmosphere. Keeping within these limitations is necessary for efficient
application. Optimum grain yields were obtained with the application of 120
pounds of nitrogen. In 1972, grain yields were essentially the same whether
anhydrous ammonia was applied in the irrigation water or applied mechanically.
in 1973* water applied anhydrous ammonia'gave significantly better yields than
mechanically applied ammonia.
74»03F-111
UPWARD WATER MOVEMENT ON FIELD CORES,
Welle* L.G.
jcentucky University, Lexington, Department of Agricultural Engineering.
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Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 15 fig, 2 tab, 25 ref.
Descriptors: *Subsurface irrigation, *Soil water movement, Irrigation,
Irrigation design, Irrigation systems, Hydraulic conductivity, Model studies,
Soil properties.
Subirrigation experiments were conducted under various initial and boundary
conditions using large, undisturbed soil cores representing two field soils.
Water flow volumes and pressure potential distirbutions were monitored contin-
uously during each test. The desorption soil water characteristic was determined
for both soils using pressure plates. The effective saturated hydraulic
conductivity was determined for each core used in the experiments. The
relationships between hydraulic conductivity and pressure potential, K(k), was
determined for each soil type from transient pressure potential measurements
during a drainage event. An approximate model was developed to describe
vertical water movement during subirrigation. The model assumed that the water
rises uniformly in the profile, making no provision ror water movement in
advance of the water table. The model is capable of considering profile
stratification. Also the one dimensional h-form of the Richards equation was
solved numerically for conditions corresponding to those imposed during the
experiment.
74:03F-112
MODELING INFILTRATION AND REDISTRIBUTION OF SOIL WATER DURING INTERMITTENT
APPLICATIONS,
James, L.G. and Larson, C.L.
Minnesota University, St. Paul, Department of Agricultural Engineering.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 17 fig, 2 tab, 22 ref.
Descriptors: *Model studies, *Computer models, *Infiltration, Soil water, Soil
water movement, Wetting, Infiltration rates.
A model based on equations that use measured physical parameters to represent
the infiltration and redistribution of soil water during intermittent water
applications with reasonable simplicity and accuracy is needed. A computer
model combining the work of other researchers was developed to fulfill this
need. Inputs required by the model include the soils' saturated conductivity
and moisture content, its approximate conductivity-moisture content and
conductivity-capillary pressure relationships, its initial moisture content as
well as the distance from the soils' surface to its lower boundary. Model
output includes the depths and moisture contents of both primary and secondary
wetting fronts, the rates of infiltration, surface and subsurface supply as well
as the total volume of water applied, infiltrated and supplied to surface and
subsurface runoff. Experimental laboratory data for a graded silica sand was
collected and compared to model predictions. Results presented indicate that
the model does an excellent job of predicting the volume of water stored in the
soil zone as well as the times when surface and subsurface runoff begin. It
also gives excellent predictions of infiltration rate and surface and subsurface
runoff supply rates when the application rate is less than or equal to the soils'
saturated conductivity.
74:03F-113
OPTIMIZATION OF WATER USE EFFICIENCY UNDER HIGH FREQUENCY IRRIGATION: II SYSTEM
SIMULATION AND DYNAMIC PROGRAMMING, O«IMI
Howell, T.A., Hiler, E.A., and Reddell, D.L.
Texas A&M University, College Station, Agricultural Engineering Department.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 3 fig, 5 tab, 17 ref.
Descriptors: Optimization, Dynamic programming, Simulated rainfall, Simulation
analysis, Monte Carlo method.
An environmental simulation model (temperatrue, rainfall, and potential
evaporation) was developed for Temple, Texas. Using Monte Carlo techniques,
daily environmental data could be simulated for input to the soil water balance
model. The simulation results adequately represented the stochastic serial-
correlation of these variables. Stochastic dynamic programming was used to
maximize yield, subject to water availability constraints. These results
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showed the proper irrigation decision for each period of the soil water content
and amount of irrigation water at the start of the period were known. Finally,
these results demonstrated that the irrigation amount could be substantially
reduced without a large decrease in expected yield if the irrigation water was
distributed optimally over the season. This study demonstrated the tremendous
possibilities of applying the techniques of system simulation, dynamic program-
ming and decision analysis to the irrigation problem.
74:03F-114
SIMULATION OF CROP RESPONSE TO ENERGY INPUTS,
Williams, D.W. and Chancellor, W.J.
VPI & SU, Blacksburg, Virginia, Agricultural Engineering Department.
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 11 fig, 8 tab, 11 ref,
3 append.
Descriptors: *Mathematical models, Crop production, California, Simulation
analysis.
Mathematical models of crop yields as a function of five energy-related inputs
were developed for California agriculture. The models were used in a computer
sumulation to determine the effects of shortages of the inputs upon total
crop production.
74:03F-115
OPTIMIZING WATER UTILIZATION THROUGH MULTIPLE CROPS SCHEDULING,
Huang, W., Liang, T., and Wu, I.
Hawaii University, Honolulu, Agricultural Engineering Department.
presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 8 fig, 6 tab, 19 ref.
Descriptors: *Water utilization, Scheduling, Optimization, Linear programming,
Model studies.
A deterministic linear programming model is developed for optimal use of water
resources in a small Hawaiian reservoir system. Results from the application
of the model show that through multiple cropping schemes, efficient use of
water can be achieved and production acreage can be expanded.
74:03F-116
FIELD TEST OF SOIL WATER FLUX METERS,
Dirksen, C.
U.S. Salinity Laboratory, Riverside, California.
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 4 fig, 1 tab, 5 ref.
Descriptors: *Soil water movement, Drainage, Soil investigations, Soil
moisture, Soil properties.
Soil water flux in a draining soil profile was measured with flux meters
featuring variable hydraulic resistances. As the hydraulic conductivity of
the soil changes, the meter resistance is adjusted such that the overall
hydraulic head loss across the meter matches that measured with tensiometers
in undisturbed soil nearby. The soil water flux is then equal to that through
the meter and is derived from the calibration of the resistance. If this
match is not quite perfect, the remaining small amount of divergence or con-
vergence of flow is calculated with an empirical relationship, independent of
the magnitude of the flux and the hydraulic properties of the soil. The -soil
water fluxes were measured in essentially undisturbed soil, since the meters
were installed from a horizontal direction. Such installation is possible by
using a compression spring that pushes thin filter plated against the top and
bottom of undisturbed soil surfaces excavated to a certain size with a specially
designed apparatus. A slanted pin used to constrain the spring permits the
meter to be installed and retrieved repeatedly. Two flux meters of different
sizes and with different hydraulic resistances were tested side by side in a
field plot and gave consistent, satisfactory results.
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74:03F-117
"CHAMBER METHOD" FOR DRIP IRRIGATION SYSTEM DESIGN AND INSTALLATION PROCEDURES,
Pira, E.S.
Massachusetts University, Amherst, Food and Agricultural Engineering
Department.
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 6 fig, 2 tab, 6 ref.
Descriptors: *Irrigation design, *Head loss, *Design criteria, Irrigation
methods, Flow rates, Irrigation, Agriculture.
High pressure water is supplied through a "quick-fill" and pressure reducing
means to a low pressure distribution chamber. Relatively uniform pressure
along the length of the chamber produces relatively uniform flow from the
drippers. System designs, components, and installation procedures based on
laboratory and field tests are discussed. Conclusions drawn from this work
are: (1) Darcy's pressure loss equation and Bernoulli's flow equation provide
a basis for designing chamber method irrigation systems; (2) Drippers with
tubing segments attached as described will eliminate dripper failure problems;
(3) The chambers must be charged rapidly for efficient system operation; (4)
The diameter of the chamber is the determining factor which limits the number
of drippers that can be used and the maximum chamber length; (5) Relatively
uniform pressures can be maintained from the beginning to the end of the
chamber, at low flow rates. Consequently, flow from the drippers is relatively
uniform; and (6) Flow rates from the drippers can be adjusted by changing the
pressure in the chamber.
74:03F-118
MOISTURE AVAILABILITY AND CROP PRODUCTION,
Hargreaves, G.H.
Utah State University, Logan.
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 1 fig, 2 tab, 7 ref.
Descriptors: *Crop production, *Moisture availability, Moisture deficit,
Evapotranspiration, Irrigation, Irrigation design.
Although yield data are available for agricultural crops at many locations,
there is a scarcity of data relating yield to moisture availability. Improved
evaluation of the effect of moisture could be accomplished through improved
standardization and more uniformity in reporting procedures. Many interacting
factors result in various levels of crop yields. However, there is a surpri-
sing degree of uniformity in response to level of moisture availability when
data from various experiments are analyzed in a standardized manner. General
acceptance of more complete and thorough methods for the quantitative evaluation
of moisture deficiencies will improve the valuation of climate as a resource
to be considered in development. The metholology given also provides a useful
tool for irrigation development planning, irrigation design and the scheduling
of irrigation applications.
74:03F-H9
GRAIN SORGHUM EVAPOTRANSPIRATION AND WATER. USE EFFICEINCY UNDER TRICKLE
IRRIGATION,
Howell, T.A. and Hiler, E.A.
Texas ASM University, College Station, Department of Agricultural Engineering.
Presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 5 fig, 3 tab, 38 ref.
Descriptors: *Grain sorghum, *Evapotranspiration, Irrigation practices,
Irrigation systems, Irrigation.
This research demonstrates a potential for increasing WUE of grain sorghum by
utilizing trickle irrigation to apply frequent, but small irrigation quantities
and limiting these applications according to the stage of plant development.
The findings of this research indicate that water deficits which- occur before
the milk to soft dough stage of grain sorghum development can reduce yield
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and water use efficiency. However, careful regulation of the irrigation
quantity to minumize water deficits during those periods can increase water
use efficiency. Stage II (boot to bloom) is the most critical period. Utili-
zing an existing soil water balance model to determine plant transpiration
further reinforced this conclusion when the yield per unit of transpired water
was computed.
74:03F-120
COMPARING TRICKLE, SUBSURFACE AND SPRINKLER IRRIGATION SYSTEMS,
Brosz, D.D. and Wiersma, J.L.
South Dakota State University, Brookings, Water Resources Institute.
presentes at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 5 fig, 7 tab, r ref.
Descriptors: *Subsurface irrigation, *Sprinkler irrigation, Irrigation systems,
Crop response, Corn, Potatoes, Irrigation efficiency.
Three years of data was collected on yield responses of potato and hybrid corn
crops irrigated by trickle, subsurface, and sprinkler irrigation systems. The
study was conducted on field plots which included six irrigation system design
treatments that were replicated three times. The design treatments included
every row and every other row trickle and subsurface irrigation, small frequent
sprinkler application, and larger, less frequent sprinkler applications. Indi-
cations are that potato and corn production could be increased by 5 to 15 per-
cent with 20 percent less water applied through the use of trickle and subsur-
face irrigation. A water savings in the neighborhood of 30 to 40 percent
could possibly be achieved with trickle and subsurface irrigation for yields
that are essentially the same as those obtained with sprinkler irrigation.
Tricke and subsurface irrigation systems do allow for a more efficient water
management operation. Tensiometers installed in the research plots did show
that the soil water tension was higher for the trickle and subsurface plots.
The irrigation system design treatments had no effect on potato crop maturity
or quality. The sprinkler irrigation system design that applied small, frequent
water depths did have an effect on the grain quality of a corn crop in the
black masses of spores that appeared on the ears of the corn plant.
74:03F-121
A COMPARISON OF N-DEPLETED AND N-ENRICHED FERTILIZERS AS TRACERS,
Starr, J.L., Broadbent, F.E., and Stout, P.R.
California University, Davis, Department of Soils and Plant Nutrition.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 266-267, March-
April, 1974. 1 fig, 1 tab, 3 ref.
Descriptors: Fertilization, Nitrogen, Isotope studies, Crop response.
ni4)NH4)2S04 from which virtually all (15)N had been removed was compared as
a tracer with (NH4)2S04 containing 8.95% (15)N excess in a plant uptake exper-
iment using soil columns maintained at 1/3 bar tension and conventional green-
house pots. Uptake of fertilizer nitrogen in three cuttings of ryegrass was
identical with the two fertilizers. Estimates of residual fertilizer N in the
pots agreed less closely, owing to the high dilution factor.
74:03F- 122
INFLUENCE OF ORGANIC NITROGEN ON SOIL NITROGEN, NODULATION, NITROGEN FIXATION,
AND YIELD OF SOYBEANS,
Bezdicek, D.F., Mulford, R.F., and Magee, B.H.
Maryland University, Department of Agronomy.
qoil Science Society of America Proceedings, Vol. 38, No. 2, p 268-273, March-
April/ 1974. 2 fig, 5 tab, 17 ref.
Descriptors: *Fertilization, Nitrogen, Nitrogen fixation, Soybeans, Crop
response.
Nitrogen was applied on a previous rye cover crop for later determination of
tne effect of organic N on soybean, N2-fixation rate, plant dry matter, N up-
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take, and yield. Nitrogen was applied at, 0, 56, 112, and 224 kg N/ha as
NH4N03 or urea either on rye in mid-March or at soybean planting time in a
4x2x2 factorial design. In both years of study, N2-fixation rate as
estimated from acetylene reduction was reduced throughout the season by in-
creased fertilization rate. For 1 year, interactions showed that N2-fixation
rate and nodule mass were stimulated late in the season from increased N fertil-
izer applied to the rye but not at soybean planting. Interactions between
NH4N03 as compared with urea and time of application showed that NH4NO3 as
compared with urea applied on rye significantly increased soybean dry matter,
N uptake, and yield. Urea applied at planting increased these parameters in
comparison with NH4N03. The observed increases in dry matter, N uptake, and
yield from rye-applied NH4N03 were not accompanied by a corresponding increase
in N2-fixation rate or nodule mass. This would suggest that the N2 fixing
system was not responsible for the increase of dry matter, N-uptake, and yield.
Soil organic N was not measureably influenced by the treatments imposed.
74:03F-123
SOIL PHOSPHORUS AVAILABILITY AS MEASURED BY DISPLACED SOIL SOLUTIONS, CALCIUM-
CHLORIDE EXTRACTS, DILUTE-ACID EXTRACTS, AND LABILE PHOSPHORUS,
Soltanpour, P.N., Adams, F., and Bennett, A.C.
Colorado State University, Ft. Collins, Dept. of Agronomy.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 225-228, March-
April, 1974. 4 fig, 17 ref.
Descriptors: Fertilizers, Fertility, Soil tests, Sorghum, Crop response,
Phosphorus.
Five rates of Ca(OH)2 and four rates of Ca(H2PO4)2-H20 were added in all
combinations to samples of a P-deficient, low pH, sandy loam soil. The treated
soil was subjected to several wetting-drying-pulverizing cycles to facilitate
equilibrium. Soil solutions were subsequently displaced from subsamples and
analyzed; other subsamples were extracted for P with CaC12 and silute acid;
"labile P" was determined on subsamples from each treatment; a sorghum-sudan-
grass hybrid was grown in the greenhouse to measure P availability.
Maximum yield of test plants was obtained at about 22 micro-m of P in the dis-
placed soil solution, 12 micro-m of P in the CaC12 extract, 80 ppm P on soil-
weight basis in dilute-acid extract, and 50 ppm of "labile P" on soil-weight
basis. Tne V uptake was nighly correlated with the logarithm of P concentra-
tion in soil solution and CaCl2 extract, logarithm of "labile P" and concen-
tration of P in dilute acid extract. All index were nearly equal as indicators
of P availability.
74:03F-124
RATE OF PHOSPHORUS SORPTION BY FIVE OKLAHOMA SOILS,
Enfield, C.G.
National Water Quality Control Research Program.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 404-407, May-
June, 1974. 7 fig, 1 tab, 14 ref.
Descriptors: Fertilizers, Fertilization, Phosphorus, Equations, Sorption,
Oklahoma.
Two equations are evaluated in relation to their suitability as rate equations
for phosphorus sorption by selected Oklahoma soils. The rate equation which
best fits experimental data was ds/dt = a(C to the b power)(S to the c power)
where S is the sorbed concentration (mass per unit weight of the soils), C is
solution concentration (mass per unit weight of the solution), t is time and
a, b. and c are constants.
74:03F-125
ACCRETION AND DILUTION OF NUTRIENTS IN YOUNG CORN, AS AFFECTED BY YIELD RESPONSE
TO NITROGEN, PHOSPHORUS, AND POTASSIUM,
Terman, G.L. and Allen, S.E.
Tennessee Valley Authority, Muscle Shoals, Alabama, National Fertilizer Deveiop-
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ment Center, Soils and fertilizer Research Branch.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 455-460, May-
June, 1974. 5 fig, 1 tab, 13 ref.
Descriptors: Fertilizers, Nutrient removal, Nutrients, Nitrogen, Phosphorus,
Potassium, Corn, Crop response.
Hybrid corn was grown in infertile soil fertilized with none and three nonzero
rates of N, P, or K, in separate treatment series; other nutrients were applied
in each series at uniform levels. Near-linear increases in uptake of N, P, or
K with amount applied occurred during 25, 41, and 53 days' growth. Concentra-
tions of N,P, or K increased with amount applied and decreased with continued
growth in each series; uniformly applied P and K, N and K, or N and P were
diluted with increase in dry matter resulting from continued growth and yield
response to increasing amounts of the third nutrient. Yield-concentration
relationships in the N response series were similar for N, Ca, Mg, Mn, and Zn.
Response to P or K resulted in dilution of all other nutrients. Concentrations
of total cations increased with concentrations of N in each response series;
the reverse was true with P and K. Thus, the results suggest that a positive
relationship between dry matter yields and total cations (C), total inorganic
anions (A), and C-A depends on whether yield response is due to N or to other
growth-limiting factors.
74:03F-126
A TWO-PHASE MODEL FOR THE MISCIBLE DISPLACEMENT OF REACTIVE SOLUTES IN SOILS,
Skopp, J. and Warrick, A.W.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 545-550, July-
August, 1974. 5 fig, 1 tab, 32 ref.
Descriptors: *Modes studies, Solutes, Adsorption, Deffusion, Connection.
Miscible displacement is studied by considering the flow regime to be composed
of separate mobile and stationary phases. Solute transfer through the mobile
phase occurs only by convection, whereas adsorption or reaction by the soil
matrix is diffusion limited and occurs normal to the mobile-stationary inter-
face. The model is unique in that a specific rate law is not assumed, but the
solution is exact. Results are presented graphically as a function of two
parameters which are compared with experimental results of other workers. The
displacement of calcium by magnesium was more closely in agreement with theo-
retical predictions than was adsorption of picloram.
74:03F-127
TIME-DEPENDENT LINEARIZED INFILTRATION: II. LINE SOURCES,
Lomen/ D.C. and Warrick, A.W.
Arizona University, Tucson, Dept. of Mathematics.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 568-572, July-
August, 1974. 6 fig, 12 ref.
Descriptors: *Infiltration, *Soil water movement, *Mathematical studies, *Unsat-
urated flow, *Soil water. Irrigation practices, Irrigation effects, Irrigation
systems, Irrigation, Agriculture, Irrigation water.
Water flow from line sources is analyzed using a linearized form of the moisture
flow equation. Both single and parallel line sources are considered. Results
are particularly relevant for high-frequency irrigation such as by trickle
sources, for which the soil moisture at any particular point varies over a
relatively small range. Numerical calculations include lines of constant matric
flux potential (or equal moisture content) as a fucntion of time and the time-
dependent response to a cyclic input. Although the results are developed for
surface sources, the analysis may easily be extended to buried sources.
74:03F-128
SOLUTION TO THE ONE-DIMENSIONAL LINEAR MOISTURE FLOW EQUATION WITH WATER
EXTRACTION,
Warrick, A.W.
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Arizona University, Tucson, Dept. of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 573-576, July-
August, 1974. 3 fig, 2 tab, 8 ref.
Descriptors: *Soil water movement, *Infiltration, *Mathematical studies,
*Unsaturated flow, *Soil water, Irrigation practices, Irrigation effects,
Irrigation systems, Irrigation, Agriculture, Irrigation water.
The one-dimensional, steady-state moisture flow equation is solved for arbitrary
plant water withdrawal functions using the matric flux potential of earlier in-
vestigators to obtain a linearized form. A semi-infinite flow medium and a
finite-depth medium overlying a shallow water table are considered with the
surface boundary condition taken as a flux. Tables are presented giving the
matric flux potential (from which the pressure head is easily determined) for
several withdrawal functions. Numerical examples show the effects of different
surface fluxes and rooting depths on the matric flux potential and pressure-
head profiles. The results are particularly relevant for high-frequency irri-
gation.
74:03F-129
EFFECT OF SALTS AND SALTS PLUS NITROGEN-15-LABELED AMMONIUM CHLORIDE ON MINERAL-
IZATION OF SOIL NITROGEN, NITRIFICATION, AND IMMOBILIZATION,
Westerman, R.L. and Tucker, T.C.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 602-605, July-
August, 1974. 1 fig, 5 tab, 11 ref.
Descriptors: *Nitrogen, *Nitrification, Salinity, Salts, Ammonium compound.
The effects of 0.0, 0.01, and 1.0 N concentrations of sodium, copper and calcium
chloride salts added to a Pima clay loam with and without (15)NH4C1 on mineral-
ization of soil nitrogen, nitrification, and immobilization were measured over
a 49-day period. Dilute concentrations of salt, (15)NH4C1, and dilute salts
plus (15)NH4C1 stimulated mineralization of soil N. The "priming effect" was
shown to be real and not just a simple exchange. Nitrification of native
ammonium nitrogen and (15)N-labeled ammonium decreased with increasing concen-
trations of salt. High concentrations of copper and calcium chloride salts
inhibited nitrification of (IS)N-labeled ammonium more than sodium salts.
Immobilization of (15)NH4(+)-N was decreased significantly by high concentrations
of salt. Gaseous loss processes were decreased with increased salts.
74:03F-130
WATER REPELLENT SOIL MULCH FOR REDUCING FERTILIZER NUTRIENT LEACHING: II.
VARIABLES GOVERNING THE EFFECTIVENESS OF A SILICONS SPRAY,
Snyder, G.H., Ozaki, H.Y., and Hayslip, N.C.
Dow Corning Corporation, Midland, Michigan.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 678-681, July-
August, 1974. 4 tab, 7 ref.
Descriptors: *Mulching, *Nitrogen, Potassium, *Leaching, *Nutrients, Sweet Corn.
Nitrogen and potassium from a fertilizer band in sand soils was reduced by
creating a mulch of water repellent soil over the band using a siliconate
spray. Best results were obtained using a 1% siliconate spray in quantities
sufficient to penetrate about 4 cm over a region 20 cm wide, on the flat surface
of raised vegetable beds. Mulches created on peaked beds were ineffective in
reducing leaching, probably due to erosion of the mulch. Sweet corn yields
are comparable to those obtained by protecting N and K with plastic mulch or
by applying N and K in split applications.
74:03F-131
PREDICTING EXCHANGEABLE SODIUM RATION IN IRRIGATED TROPICAL VERTISOLS,
Sinanuwong, S. and El-Swaify, S.A.
Hawaii Institute of Geophysics.
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Soil Science Society of America Proceedings, Vol. 38, No. 5, p 732-737,
September-October, 1974. 7 fig, 7 tab, 12 ref.
Descriptors: *Sodium, Hawaii, Soil properties, Soil chemical properties, Soil
chemistry, Soil tests.
Batch equilibrium studies were used to investigate Nadivalent exchange and to
derive Capon constants for three Hawaii Vertisols. Obtained regression coeffic-
ient values indicated that a linear relationship exists between exchangeable
sodium ration (ESR) and sodium adsorption ratios (SAR) for tropical Vertisols.
ESR values obtained for two of the soils were slightly lower than the values
predicted by Bower's equation and higher than those predicted by the U.S.
Salinity Laboratory's equation. ESR values obtained for the third soil were
lower than those predicted by either equation. Generally, the higher prefer-
ences fo surface than of subsurface horizons for Na was confirmed. Prevailing
electrolyte concentration levels were found more important than any other ex-
perimental variable on affecting the precision fo ESR estimates for a given
SAR. Although ESR values were generally higher at O.lN, the valence-dilution
effect was reversed for the surface horizon of one Vertisol during Mg-Na ex-
change. While little difference was noted between Ca-Na and Mg-Na exchange in
one of the soils, in the other two significantly smaller ESR values were ob-
tained for the first than for the second reaction. An unexpected type of
hysteresis effect was noted, whereby divalent-soils exhibited greater preference
for Na than did Na-soils. Possible reasons for this effect are discussed.
74:03F-132
NITRIFICATION AND DENITRIFICATION DURING MISCIBLE DISPLACEMENT IN UNSATURATED
SOIL,
Kirda, C., Starr, J.L., Misra, C., Biggar, J.W., and Nielsen, D.R.
California University, Davis, California.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 772-776,
September-October, 1974. 5 fig, 1 tab, 15 ref.
Descriptors: *Nitrifioation, *Denitrification, Leaching, Diffusion, Soil water,
Soil properties, Soil chemistry, Unsaturated flow.
Nitrification and denitrification during the leaching of a pulse of NH4N03
applied to the surface of soil columns are analyzed experimentally and theoret-
ically. Experimentally, unsaturated soil columns of two lengths were leached
steadily with a tracee solution containing NH4NO3 while the air-filled portions
of the columns were being flushed simultaneously with air. During these steady
state conditions, a pulse of tracer solution containing either 15NH4(+) or
15N03(-) was leached through the columns. The words tracee and tracer signify
that both solutions were chemically identical with the latter containing a
greater proportion of 15N. Steady-state tracee concentration distributions
within the columns as well as the transient tracer concentration distributions
in the effluent were analyzed assuming first-order kinetics. Values of both
the rate coefficients and the concentration distributions stemming from the
tracee and tracer measurements were in general agreement. The agreement between
the measured and theoretical results are discussed in terms of soil water
properties and the kinetics of microbial populations.
74:03F-133
<3ALT TOLERANCE OF MEXICAN WHEAT: II. RELATION TO VARIABLE SODIUM CHLORIDE
AND LENGTH OF GROWING SEASON,
BernaL- C.T., Bingham, F.T., and Oertli, J.
California University, Riverside, Department of Soil Science and Agricultural
Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 777-779,
September-October, 1974. 7 fig, 2 tab, 15 ref.
Descriptors: *Wheat, Crop response, Crop production, Germination, Salinity,
Salt tolerance.
Germination, seedling growth, and grain production ofi four short-season, one
intermediate-season, and three long-season varieties of Mexican wheat were
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studied in relation to variable NaCl salinity. Germination counts after 7 days
exposure to NaCl solutions in petri dishes revealed that the wheats as a group
are relatively tolerant, germinating freely in the presence of -16 to 20-atm
osmotic potential. Tolerance at germination was not associated with any obvious
properties such as length of growing season or seed hardness. The eight wheat
varieteis were grown from seedling stage to maturity on sand cultures with a
complete nutrient solution containing sufficient NaCl to produce total osmotic
potentials of 0.5, 2.5, and 4.5 atm. Plots of relative grain yield in relation
to osmotic potential of substrate revealed two general relationships, one for
the short-season varieties and one for the long-season varieties.
74-.03F-134
RICE RESPONSE TO NITROGEN AND PHOSPHORUS IN FLOODED AND NONFLOODED SOILS,
Terman, G.L. and Allen, S.E.
Tennessee Valley Authortiy, Muscle Shoals, Alabama, National Fertilizer
Development Center, Soils and Fertilizer Research Branch.
Soil Science Society of America Proceedings, Vol^ 38, No. 5, p 780-784,
September-October, 1974. 3 fig, 5 tab, 12 ref.
Descriptors: *Rice, Nitrogen, Nitrification, Phosphorus, Crop response, Green-
house, Flood irrigation, Flooding.
Pot experiments were conducted in a greenhouse to study nutrition of rice under
flooding and upland conditions. Yields of rice grown in one experiment on
Mountview silt loam increased rectilinearly with 0-, 400-, and 800-mg rates of
N/pot (5 kg of soil). Concentrations of N in grain + straw at maturity were
uniformly low. Multiple rates of N from 250 to 2,000 ing/pot and P from 0 to
1/000 mg/pot (6.25 kg of soil) were applied for Nato rice grown on Mountview
silt loam and Sango silty clay loam in a second experiment. Marked yield re-
sponses to N and P were obtained. Yields of straw and of grain + straw, N up-
take, and N recovery were higher on nonflooded than on flooded soils. Grain
yields, however, were slightly higher with flooding. Uptake of N, P, Ca, Mg,
Mn, and Zn increased with yield response to N and P, while K uptake decreased
on the Mountview soil. Concentrations of N and P increased with applied N and
P,.respectively, while concentrations of other nutrients were diluted in most
situations with yield response to N or P on both flooded and nonflooded soils.
These results indicate that with adequate applied nitrients, especially N, yields
of rice with adequate water but without flooding can equal or even exceed those
under flooding.
74:03F-135
MODIFIED PENMAN EQUATION TO PROVIDE THE UPPER BOUNDARY CONDITION ON COMPUTING
EVAPORATION FROM SOIL,
Staple, W.J.
Soil Research Institute, Agriculture Canada, Ottowa, Ontario.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 837-839,
September-October, 1974. 2 fig, 16 ref.
Descriptors: *Evaporation, Vapor pressure, Soil, Soil water movement, Drying.
Penman's equation for potential evaporation was modified by including in it the
relative vapor pressure h of partially dried surface soil. The modified equa-
tion was used to predict evaporative flux from drying soil as a boundary cond-
ition in the finite difference solution of the flow equation. The method gave
satisfactory agreement in a 20-day test in which evaporation was measured from
short columns of soil in a fallowed plot.
74:03F-136
DIURNAL SOIL-WATER EVAPORATION: COMPARISON OF MEASURED AND CALCULATED SOIL-
WATER FLUXES,
Jackson, R.D., Reginato, R.J., Kimball, B.A., and Nakayama, F.S.
U.S. Water Conservation Laboratory, Phoenix, Arizona.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 861-866,
November-December, 1974. 8 fig, 2 tab, 20 ref.
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Descriptors: Soil water movement, Soil water, Diffusivity, Evaporation,
Theoretical analysis.
The Philip and DeVries theory and the "isothermal" theory were used to predict
diurnal soil water fluxes near the soil surface. The predicted values were
compared with those obtained by measurements of soil-water content, soil temper-
ature, and evaporation. Previously measured soil-water diffusivities were
used in the theoretical calculations. The thermal vapor diffusivities were
calculated using both the "simple" and the "complete" theory of Philip and
DeVries. Comparison of measured and calculated fluxes indicated that the theory
of Philip and DeVries predicts the measured values better at intermediate water
contents, but the "isothermal" theory predicts values better at high and very
low water contents.
74:03F-137
TWO-DIMENSIONAL WATER INFILTRATION FROM A TRENCH IN UNSATURATED SOILS,
Sawhney, B.L. and Parlange, J.-Y.
Connecticut Agricultural Experiment Station, New Haven.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 867-871,
November-December, 1974. 8 fig, 2 tab, 10 ref.
Descriptors: *Infiltration, Trenches, Unsaturated flow, Soil Water movement
Moisture tension, Seepage.
Two-dimensional infiltration of water from finite trenches was observed in
three soil samples with different textures. The vertical infiltration is
slowed by the lateral infiltration and the slowing is inversly proportional
to the width of the trench. Furthermore, the vertical infiltration is about
twice as fast as the lateral infiltration for all soils tested. At the same
relative distance from the trench, the soil was drier beside than below the
trench. Our observation and interpretations agree with numerical simulations
of Selim and Kirkham.
74:03F-138
NOMOGRAPHIC INTERPRETATION OF WATER ABSORPTION DATA IN TERMS OF A TWO-PARAMETRIC
DIFFUSIVITY-WATER CONTENT FUNCTION,
Stroosnijder, L. and Nolt, G.H.
State Agricultural University, Wageningen, The Netherlands, Dept. of Soils and
Fertilizers,
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 876-880,
November-December, 1974. 5 fig, 2 tab, 13 ref.
(See 74:020-030)
74-03F-139
UNSTEADY, UNSATURATED, N-DIMENSIONAL MOISTURE FLOW IN SOIL: A COMPUTER
SIMULATION PROGRAM,
Van der Ploeg, R.R. and Benecke, P.
Georg-August University, Goettingen, West Germany.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 881-884,
November-December, 1974. 7 fig, 1 tab, 15 ref.
Descriptors: *Computer models, *Computer programs, *Simulation analysis,
Mathematical models, Unsaturated flow, Soil water movement, Unsteady flow,
Soil water, Absorption.
A computer simulation program for prediction n-dimensional moisture flow in
soils is simple to program and does not require extensive mathematical back-
ground. The programming was done with the computer program System/360 Continu-
ous System Modeling Program (CSMP). For a number of selected problems the
simulation results were compared with existing analytical and numerical solu-
tions, and good agreement was found. Comparisons are made for 1-dimensional
adsorption, 3-dimensional (spherical) absorption, 2-dimensional filtration
from a line-source and a 3-dimensional infiltration from a point source.
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74:03F-140
COMPARATIVE EFFICIENCY OF SOLUBLE AND CONTROLLED-RELEASE SULFUR-COATED UREA
NITROGEN FOR CORN IN TROPICS,
Dalai, R.C.
West Indies University, St. Augustine, Trinidad.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 790-794,
November-December, 1974. 3 fig, 5 tab, 11 ref.
Descriptors: *Nitrogen, *Urea, *Nitrification, Corn, Crop response, Nutrients.
The efficiency of the soluble-N sources, ammonium sulfate (AS), urea-ammonium
phosphate (UAP) and urea and controlled-release-N source, sulfur-coated urea
(SCU-8.9, SCU-1.1, and SCU-0.9) of differing N-release rates applied at 50, 100,
and 200 kg/ha of N to an acidic soil, were compared in terms of N uptake and
grain yield of corn. The apparent N recovery of added N, calculated by uptake
differences from the control plots, was evaluated from N uptake by the two
successive crops, one in the wet season and the other in the following dry
season. In general, N uptake, grain yield, and apparent N recovery were in-
creased by added N; which was opposite to the nitrification of these N sources
except that the performance of urea was better than the other soluble-N sources,
primarily because it had a smaller effect on soil pH and exchangeable Al. The
inclusion of microbicide in the S-coatings of SCU had no influence on N effici-
ency or grain yield. More N was recovered from SCU with slower N-release
characteristics irrespective of coating weight. Apparent recovery of added N
was almost complete from urea, SCU-8.9, SCU1.1 and SCU-0.9 when applied at the
rate of 50 kg/ha of N, although the recovery at 200 kg/ha of N was about 50%.
74:03F-141
A METHOD FOR MEASURING FIRST-STAGE SOIL WATER EVAPORATION IN THE FIELD,
Arkin, G.F., Rithcie, J.T., and Adams, J.E.
Texas Agricultural Experiment Station.
Soil Science Society of America Proceedings, Vol. 38, No. 6, p 951-954,
November-December, 1974. 5 fig, 8 ref.
(See 74:07B-006)
74:03F-142
RELATION BETWEEN NITRATE ABSORPTION AND WATER TRANSPIRATION BY CORN,
Liao, C.F.-H. and Bartholomew, W.V.
North Carolina State University, Raleigh, Department of Soil Science.
Soil Science Society of America Proceedings, Vol. 38, No. 3, p 472-477, May-
June, 1974. 5 tab, 17 ref.
Descriptors: Nitrates, Absorption, Transpiration, Leaching, Corn, Crop response,
Evapotranspiration, Diffusion.
The relationship between the absorption of NO3-N by young corn plants and the
quantity of water transpired was studied in solution and soil culture. Tracer
N was employed to measure N03 absorption. Gravimetric methods were used to
monitor evapotranspiration. From solution culture, N03 was absorbed at rates
relatively greater than water. From soil culture, NO3 was absorbed at a rela-
tive rate close to that of water when the soil was not pretreated. However,
when the soil material was wetted and leached of soluble N before planting corn,
N03 was absorbed at a relative rate 1.5 to 2.0 times that of water. In soil
situations where water was not being absorbed by plants, N03-N likewise was
not absorbed. Mass flow and diffusion both were involved in N03 transport to
roots. Prior cultural conditions had a marked influence on active uptake of
N03 presumably through an influence on speicfic rates of N absorption.
74:03F-143
EFFECT OF TRANSPIRATION RATE ON SALT ACCUMULATION AROUND CORN ROOTS IN A SALINE
SOIL,
Sinha, B.K. and Singh, N.T.
Punjab Agricultural University, Ludhiana, India, Department of Agricultural
Engineering.
Agronomy Journal, Vol. 66, No. 4, p 557-560, July-August, 1974. 1 fig, 3 tab,
11 re£.
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Descriptors: *Saline soil, Salinity, Ions, Transpiration, Salts, Corn root
zone.
Laboratory studies were conducted to determine the extent of ion accumulation
around corn roots of plants exposed to different transpiration conditions.
Ion accumulation in the apparent free space of roots, the soil adhering to the
roots, and the bulk soil was studied using a soil mixed with sodium chloride
so that the electrical conductivity of saturation extract was 3.96 mmho/cm.
Maximum ion accumulation occurred in the apparent free space of the roots,
followed by the closely adhering soil. Under high transpiration, sodium
concentration increased from 37.6 mg/100 g in the bulk soil to 90.3 mg/100
g in the soil close to the roots. After the same treatment, a threefold
increase in the chloride content of the closely adhering soil was observed.
A significant correlation existed between the rate of water loss per unit
root length and the Na and Cl concentration of the closely adhering soil.
Results indicate that under high transpiration, the salt concentration close
to the roots may be much higher than that obtained from an analysis of the
bulk soil.
74:03F-144
MODEL FOR PREDICTING PLANT YIELD AS INFLUENCED BY WATER USE,
Hanks, R.J.
Utah State University, Logan, Department of Soil Science and Biometerorology.
Agronomy Journal, Vol. 66, No. 5, p 660-665, September-October, 1974.
6 fig, 4 tab, 22 ref.
Descriptors: *Consumptive use, *Growth rates, *Model studies, Irrigation
practices, Irrigation methods, Computer models, Evaporation, Transpiration,
Moisture availability.
A model has been devised to predict plant yield, both total dry matter and
grain, as a function of water use. The model is simple and inexpensive to
run on a computer to determine seasonal yields as influenced by irrigation
frequency and amount, rainfall, matter yield of sorghum in Colorado, corn dry
matter and grain yields in Israel, and corn grain yields in Nebraska, with
various water application treatments, was found. A basic assumption is that
the ratio of actual to potential transpiration. Evaporation from the soil
is assumed to decrease with the square root of time after wetting as well as
with the stage of growth. The shape of the relative yield-water use curve
was found to be sensitive to the evaporation and transpiration assumptions
made, but insensitive to the relation used to describe the influence of
soil water status on transpiration.
74:03F-145
IRRIGATION, ROW WIDTH, AND PLANT POPULATION IN RELATION TO GROWTH CHARACTER-
ISTICS OF TWO SOYBEAN VARIETIES,
DOSS, B.D. and Thurlow, D.L.
United States Department of Agriculture, Agricultural Research Service,
Auburn, Alabama.
Agronom- Journal, Vol. 66, No. 5, p 620-623, September-October, 1974. 2 fig,
S tab, 8 ref.
Descriptors: *Soybeans, *Crop response, *Plant population, Irrigation, Moisture
stress, Irrigation practices, Soil water, Plant growth, Planting management.
Soybean yields in the past have varied considerably from year to year in the
southeastern United States. Many factors are important in soybean production,
but water stress at critical growth periods appears to be one of the most fre-
quently limiting factors. Soybeans were grown on a Lucedale fine sandy loam
soil to determine the effects of three soil water regimes at two row widths
and three plant population levels on water use, rate of plant growth, and
bean yield of two varieties. Water use rates by soybeans were influenced more
by soil water regime than by row width or variety. Average rates during the
season ranged from 0.05 to 0.84 cm/day, depending on the amount of available
water in the soil.
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74:03F-146
EFFECT OF SOIL WATER STRESS AT VARIOUS GROWTH STAGES ON SOYBEAN YIELD,
Doss, B.D., Pearson, R.W. and Rogers, H.T.
United States Department of Agriculture, Agricultural Research Service, Auburn,
Alabama.
Agronomy Journal, Vol. 66, No. 2, p 297-299, March-April, 1974. 1 fig, 2 tab,
11 ref.
Descriptors: *Moisture stress, *Soybeans, *Crop response, *Growth stages,
Irrigation practices, Irrigation effects, Irrigation.
Conventional irrigation experiments and rainfall distribution-yield studies
have indicated that insufficient water during flowering and pod-fill stages
frequently limits yields of soybeans. In this 3-year experiment, field plot
covers were used to control rainfall and water stress was imposed on plants
at various stages of growth to determine more specifically the critical periods
for irrigating soybeans for maximum yields. Soil water regimes ranged from
a limited supply (10% available soil water) to adequate water (50% available)
during the entire growing season. More bean production was obtained from
water applied after full bloom than earlier. The pod-fill stage, from August
15 to September 20 for 'Bragg1 soybeans at Thorsby, Alabama, was the critical
time for adequate water for maximum yields. Yields from adequately watered
soybeans were 540 to 1,040 kg/ha, or 24 to 55%, greater than where water was
limited throughout the growing season. Highest yield obtained under the best
water regime was 3,320 kg/ha. Conditions limiting yields were not obvious.
74:03F-147
DESIGNING TRICKLE IRRIGATION LATERALS FOR UNIFORMITY,
Howell, e.A. and Hiler, E.A.
Texas A&M University, College Station, Department of Agricultural Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 443-454, December, 1974. 9 fig, 11 ref,
2 append.
(See 74:08A-002
74:03F-148
ECONOMIC PIPE SIZING IN PUMPED IRRIGATION SYSTEMS,
Perold, R.P.
Stellenbosch University, Republic of South Africa, Department of Agricultural
Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 425-551, December, 1974. 7 fig, 1 tab, 11 ref,
2 append.
(See 74:08A-003
74:03F-149
SURFACE PLUGGING DURING BASIN RECHARGE OF TURBID WATER,
Jones, O.R., Goss, D.W., and Schneider, A.D.
United States Department of Agriculture, Southwestern Great Plains Research
Center, Bushland, Texas.
Transactions of the ASAE, Vol. 17, No. 6, p 1011-1014 & 1019, November-December
1974. 7 fig, 2 tab, 9 ref.
Descriptors: *Recharge, *Recharge ponds, Groundwater, Groundwater basins,
Groundwater recharge, Turbidity.
The following conclusions were made as a result of investigations on the
Southern High Plains to artificially recharge the Ogallala aquifer with turbid
storm runoff through excavated basins: 1) Most suspended solids in playa
water were deposited on or near the surface during basin recharge, except
during test where cracking of the basin surface while flooded allowed sediment
deposition at undetermined depths below the basin surface; 2) Although plugging
was related to the amount of suspended solids introduced into the basin with
the recharge water, the total amount of suspended solids required to cause
plugging varied by an order of magnitude between tests; 3) The major factor
limiting recharge of tubid water through excavated basins was plugging on or
near the surface.
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74:03F-150
MIXING IN SPRINKLER IRRIGATION SYSTEMS,
Hermann, G.J., McMaster, G.M. and Fitzsimmons, D.W.
CH2M/H111, Redding, California, Agricultural Engineering.
Transactions of the ASAE, Vol. 17, No. 6, p 1020-1024 & 1028, November-December
1974. 6 fig, 9 ref.
(See 74:08A-004)
74:03F-151
ANALYSIS OF CANAL SEEPAGE TO INTERCEPTOR DRAIN,
Sharma, H.D. and Chawla, A.S.
O.P. Irrigation Research Institute, Roorkee, India.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 351-369, September, 1974. 11 fig, 5 ref,
2 append.
(See 74:08A-006)
74:03F-152
IRRIGATION MANAGEMENT FOR SALT CONTROL,
van Schilfgaarde, J., Bernstein, L., Rnoades, J.D. and Rawlins, S.L.
United States Department of Agriculture, Riverside, California, Agricultural
Research Service, U.S. Salinity Laboratory.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 321-338, September, 1974. 8 fig, 5 tab,
27 ref, 2 append.
Descriptors: Salinity, Saline soil, Saline water, Irrigation.effects, Irri-
gation practices, Irrigation operation and maintenance, Irrigation water.
Combination of a reevaluation of established crop salt tolerance data, recent
advances in understanding of soil chemistry and application of soil physics
principles leads to a proposed management system for irrigation that can
result in significant reductions in the amount of salt discharged for irri-
gation projects. These concepts can play a major part in advancing irrigation
agriculture, while meeting the challenge of minimizing water quality degrada-
tion. Adoption will require changes in irrigation management that call for
far closer control of amount and uniformity of water applied than is customary.
74:03F-153
BASIC PRINCIPLES OF PULSE IRRIGATION,
Karmeli, D. and Peri, G.
Technion, Haifa, Israel, Faculty of Agricultural Engineering.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 309-319, September, 1974. 2 fig, 3 tab, append.
Descriptors: Irrigation systems, Irrigation practices, Irrigation effects,
irrigation design, Sprinkler irrigation, Application methods. Water conserva-
tion.
The term pulse irrigation was defined qualitatively and quantitatively.
This irrigation technique was described in terms of its main purpose which is
the achievement of low application rate with the use of an irrigation device
having a higher application rate. The present analysis based on mathematical
and engineering considerations enables the determination of the characteristics
of pulse irrigation (e.g., length of operating and resting time in a single
pulse and the number of pulses).
74:03F-154
QUANTITY AND FREQUENCY OF TRICKLE AND FURROW IRRIGATION FOR EFFICIENT CABBAGE
PRODUCTION,
Bucks, D.A., Erie, L.J. and French, O.F.
U.S. Water Conservation Laboratory, Phoenix, Arizona.
Agronomy Journal, Vol. 66, No. 1, p 53-57, January-February, 1974. 4 fig,
3 tab, 9 ref.
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Descriptors: *Crop production, *Crop response, *Consumptive use, *Evapotrans-
piration, Irrigation practices, Irrigation systems, Irrigation efficiency,
Irrigation, Agriculture.
Trickle irrigation, with its capability of small, frequent irrigation applica-
tions, has aroused considerable interest because of possible increased pro-
duction and decreased water requirements. For this reason, a replicated
f *•%.* . lnvestigation was conducted to evaluate quantity and frequency of trickle,
modified-furrow, and standard-furrow irrigations on the growth of cabbage,
using a moderately saline water on a fine-textured soil. Trickle and modified-
furrow irrigation were scheduled to supply various quantities of water based
on ratios of the plant's estimated consumptive use at frequencies of 3, 6,
and 12 days. Recorded data included yield, quality of production, and water-
use efficiency. Results indicate that the consumptive-use requirement (38 cm
of water in 1972) for high production of cabbage was about the same for all
irrigation methods. Trickle and modified-furrow irrigation, however, did
reduce furrow irrigation, showing that higher irrigation efficiencies can be
attained with these new irrigation methods as opposed to conventional methods.
74:03F-155
PREDICTING NITROGEN FERTILIZER REQUIREMENTS AFTER LAND LEVELING,
Thomas, J.R., Heilman, M.D., and Lyles, L.
United States Department of Agriculture, Weslacp, Texas.
Agronomy Journal, Vol. 66, No. 3, p 371-374, May-June, 1974. 5 fig, 4 tab,
O ITCf *
Descriptors: *Fertility, Fertilization, Fertilizers, Land forming, Land
reclamation, Land development, Crop response.
Reduced yields and nutrient-deficient crops on cut areas after land leveling
are recognized problems. The objectives of this study were to determine if
the variability in crop production between cut and fill areas of leveled
fields could be minimized without overfertilization by adjusting the soils to
a uniform level of available N based on the soil's capacity to supply N (N
index) and to relate the N fertilizer requirement to the N index. Five
leveling methods which resulted in the removal of different amounts of top
soil were used. Soils from leveled and nonleveled areas were incubated and
the soils capacity to supply N were described by the regression model. With
a 14-day incubation, the non-leveled soils supplied N at the rate of 174
kg/ha. Therefore, based on the leveled soils' ability to supply N in this
time period, sufficient NH4N03 fertilizer was applied to establish N levels
of 174, 219, and 263 kg/ha. The leveled fields were cropped to forage sorghum
Dry matter forage yields, N uptake, and the growth rate during the first
19 days of growth were significantly related to the N index.
74:03F-156
INTERACTIVE EFFECTS OF SALINITY AND FERTILITY ON YIELDS OF GRAINS AND
VEGETABLES ,
Bernstein, L. , Francois, L.E. and Clark, R.A.
United States Department of Agriculture, Agricultural Research Service,
Riverside, California.
Agronomy Journal, Vol. 66, No. 3, p 412-421, May-June, 1974. 7 fig, 2 tab,
* /
Descriptors: *Salt tolerance, Salinity, Crop response, Fertilization, Saline
soil, Corn, Wheat, Barley, Vegetable crops, Phosphate.
The salt tolerance of crops has usually been studied under optimal fertility
conditions. The objectives of the present studies were to compare crop res-
ponse to salinity when nutrients were limiting, adequate, or in excess to
guide proper fertilization of saline soils and to determine whether additional
fertilizer could restore yield losses caused by salinity. Corn, barley,
and six vegetable crops were grown to maturity in large, outdoor sand cultures
to study the interactive effects of salinity and nutrition. Increasing
levels of phosphate (0.1 to 2.0 mM) aggravated salt injury in corn and decreased
salt tolerance. Decreasing solution K from 2 to 0.4 meg/liter did not affect
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leaf K or yield of corn. Deficient levels of P or N did not consistently
decrease salt tolerance of any of the crops studied, although the wheat
and barley varieties showed erratic decreases in salt tolerance when N or P
was deficient. When N or P was severely growth-limiting, salinity affected
growth of some crops. Conversely, when salinity severely limited growth,
nutritional responses of some crops decreased.
74:03F-157
SOME EFFECTS OF SUBIRRIGATION ON BENTGRASS DURING HEAT STRESS IN THE FIELD,
Krans, J.V. and Johnson, G.V.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Agronomy Journal, Vol. 66, No. 4, p 526-530, July-August, 1974. 5 fig, 3 tab,
10 ref.
Descriptors: *Subsurface irrigation, Turf grasses, Fertilization, Root
development, Temperature, Stress, Thermal stress, Soil, Soil investigations.
The management of bentgrass in the southwestern United States presents
numerous problems to the grower because of the long period of high summer
temperatures associated with this region. This study was conducted to deter-
mine if the adverse effects of heat stress could be alleviated by subirrigation.
A field study was conducted to evaluate the merits of subirrigation on bent-
grass during a 4-month period of heat stress. Effects were evaluated from
clipping yields, chlorophyll content and root distribution. Three irrigation
treatments were applied to artificial soils of washed mortar sand and a sand-
soil mixture. Temperature adversely affected clipping yields and chlorophyll
content during excessive heat stress (30 to 35 C) early in the summer. Clipping
yields remained low, but color gradually darkened following the initial stress
period. Sprinkle irrigation and subirrigation from a fluctuating water
table resulted in similar yields, whereas subirrigation from a single stable
water table at 30 cm produced significantly lower yields. Subirrigated
plots also had significantly lower chlorophyll production than sprinkle-
irrigated plots.
74:03F-158
RELATION OF SOYBEAN LEAF WATER POTENTIAL TO SOIL WATER POTENTIAL,
Brady, R.A., Powers, W.L., Stone, L.R., and Goltz, S.M.
Kansas State University, Manhattan.
Agronomy Journal, Vol. 66, No. 6, p 795-798, November-December, 1974. 5 fig,
I tab, 12 ref.
Descriptors: Scheduling, Irrigation, Irrigation practices. Soybeans, Soil-
water-plant relationships, Soil water, Moisture stress, Moisture tension.
Estimation of plant water potential is a possible aid in irrigation scheduling.
This work examined the relation of maximum and minimum soybean leaf water
ootential to soil water potential. Maximum readings were taken near sunrise
and minimum readings were taken between 1300 and 1500 CDT. Leaf water poten-
tials were measured with a pressure chamber and soil water potentials were
estimated using moisture release curves and volumetric soil moisture measure-
ments made with a neutron probe. Leaf water potentials decreased an average
Of 9 to 10 bars as a result of daily atmospheric evaporative demand during the
vegetative stage. Soybean leaf water potential was as responsive to changes
in soil water potential during the podding stage as during the vegetative
stage. Data indicated the possibility of estimating soil water potential
from early morning values of soybean leaf, water potential.
74:03F-159
EFFECT OF PREPLANT-ONLY IRRIGATION ON COTTON YIELDS,
Bilbro, J.D. t
United States Department of Agriculture, Agricultural Research Service,
Southern Region, Lubbock, Texas.
Agronomy Journal, Vol. 66, No. 6, p 833-834, November-December, 1974. 1 fig,
4 ref.
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Descriptors: *Plant growth, *Crop response, *Cotton, Irrigation practices,
Planting management, Irrigation, Dry farming, Irrigation effects.
Irrigation practices for cotton are changing on the Texas High Plains because
the irrigation water supply is declining. The objectives of this study were
• to calculate yield probabilities for cotton planted on both early and late
dates and grown with only a preplant irrigation, and then to compare these
yield probabilities with those previously calculated for dryland conditions.
Yields from early and late plantings that had received only a preplant irriga-
tion for the period 1960 through 1971 were used for calculating probabilities
for various yield levels. The expected average yields (50% probability) of
the early and late plantings of preplant-irrigated cotton are 530 and 503 kg/ha,
respectively; and about 70% of the time the respective yields will differ by
less than 50 kg/ha. Thus, the yield potential of preplant-irrigated cotton
was not greatly affected by a wide range of planting dates. Also, 50% of the
time preplant-irrigated land can be expected to yield about twice as much as
comparable dryland and to vary much less in year-to-year yields.
74:03F-160
EFFECT OF IRRIGATION AND WATER-TABLE DEPTH ON CROP YEILDS,
Follett, R.F., Doering, E.J., Reichman, G.A., and Benz, L.C.
Northern Great Plains Research Center, Mandan, North Dakota.
Agronomy Journal, Vol. 66, No. 2, p 304-308, March-April 1974. 3 fig, 1 tab,
15 ref.
Descriptors: *Water management, *Drainage, *Corn, *Sugarbeets, *Alfalfa,
Irrigation effects, Irrigation practices, Drainage practices.
The objective in this field study was to determine the most desirable combina-
tion of amount of irrigation and degree of drainage for production of corn,
sugarbeets, and alfalfa grown on sandy soil over a declining water table.
Irrigation was applied at weekly intervals at rates of either 0, 0.5, 1.0, or
1.5 times the water requirement of the crops as predicted by the modified
Jensen-Haise equation. Irrigation amounts were applied in combination with
shallow, medium, and deep drainage. In 1971 and 1972, early season depth to
water table was 92 and 69 cm for the shallow drainage treatment, 166 and 145
cm for the medium, and 186 and 193 cm for the deep. Water-table declines
were 94 and 96 cm during the 1971 and 1972 growing seasons, respectively,
under all treatments. Corn was harvested at maturity, sugarbeets in mid-
October, and alfalfa (three cuttings) at 1/10 bloom. Maximum yields of all
crops occurred over the shallow water table; no yield response to irrigation
was observed over the shallow water table.
74-.03F-161
WATER RELATIONS OF COTTON. I. ROOT GROWTH AND WATER USE AS RELATED TO TOP
GROWTH AND SOIL WATER CONTENT,
Taylor, H.M. and Klepper, B.
United States Department of Agriculture, Agricultural Research Service, Auburn,
Alabama.
Agronomy Journal, Vol. 66, No. 4, p 584-588, July-August, 1974. 5 fig, 11
ref.
Descriptors: *Root development, *Root systems, Crop response, Moisture
tension, Moisture availability, Soil-water-plant relationships, Cotton,
Soil water.
Many experiments have evaluated the effects of decreasing soil water contents
on top growth and yield of plants, but few experiments simultaneously have
evaluated root growth. An experiment was conducted to determine the response
of cotton roots and tops to decreasing soil water content. Plants were grown
in rhizotron compartments with rainfall excluded by metal covers over the
soil. Soil profile or irrigation schedule treatments provided different
levels of soil and plant water potentials. Soil water content was determined
with a neutron probe; rooting density, from measurements of roots on the glass
viewing surface of each compartment. Plant water potential was determined
with a pressure chamber apparatus, and top growth was evaluated by plant
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height. For conditions of this experiment, cotton root growth was correlated
with decreases both in plant water potential and in soil water content.
74:03F-162
EFFECTS OF WATER MANAGEMENT AND SOIL AGGREGATION ON THE GROWTH AND NUTRIENT
UPTAKE OF RICE,
Obermueller, A.J. and Mikkelsen, D.S.
Calfiornia University, Davis, Department of Agronomy and Range Science.
Agronomy Journal, Vol. 66, No. 5, p 627-632, September-October, 1974. 5 tab,
20 ref.
Descriptors: *Water management, Soil aggregates, Crop response, Nutrients,
Nutrient requirements, Rice, Crop production, Flood irrigation, Surface irri-
gation, Irrigation practices, Root distribution.
Flooding is considered essential for the optimum growth and yield of rice
(Oryza sativa). The benefits of flooding are not well understood, even though
they have been associated with a reduction in soil moisture stress, alteration
of root development, increased availability of plant nutrients, control of
weeds, and a modified micro-climate environment. Since modification of soil
aggregation may also influence some of the same plant responses as flooding,
these effects were examined. The growth and development of rice, cv. 'Calrose,'
was closely observed from seedling stage to maturity in a controlled green-
house environment. At harvest the yield components, total yield of grain and
straw, root production and distribution, and total uptake of N, P, K, Ca, Mg,
Mn, An, Fe, and Si were determined. Rice plants grown under flooded conditions
were superior to nonflooded plants except for the first 40 days after planting.
Soil aggregation had little effect on the growth and development of flooded
rice, but nonflooded rice was benefited by the puddled soil.
74:03F-163
WATER UPTAKE BY SEEDS AS AFFECTED BY WATER STRESS, CAPILLARY CONDUCTIVITY, AND
SEED-SOIL WATER CONTACT. I. EXPERIMENTAL STUDY,
Hadas, A. and Russo, D.
Agricultural Research Organization, Bet Dagan, Israel, Division of Soil Physics,
Volcani Center.
Agronomy Journal, Vol. 66, No. 5, p 643-647, September-October, 1974. 2 fig,
1 tab, 15 ref.
Descriptors: *Germination, *Seed treatment, Moisture stress, Seeds, Soil
water, Soil-water-plant relationships, Hydraulic conductivity.
Imbibition and seed germination as affected by water potentials, hydraulic con-
ductivity, and seed-water contact area were studied. Water potential effects
were studied under perfect seed contact and unlimited hydraulic conductivity.
Effects on imbibition and germination of hydraulic conductivity and seed-water
contact were studied in an experimental setup in which separation between
these factors was made possible while a very high water potential was main-
tained. The results show that low values of external water potential affect
the rate of water uptake but not percent of germination. The rate of germina-
tion, however is affected as long as water potential is higher than a critical
value that is species-specific. For a given seed-water contact area, any
decrease in the hydraulic conductivity (or for a given conductivity, any
reduction in contact area) reduced rates of water uptake and germination;
total germination was not affected as long as the critical water potential was
not reached.
74:03F-164
WATER UPTAKE BY SEEDS AS AFFECTED BY WATER STRESS, CAPILLARY CONDUCTIVITY, AND
SEED-SOIL WATER CONTACT. II. ANALYSIS OF EXPERIMENTAL DATA,
Hadas/ A. and Russo, D.
Agricultural Research Organization, Bet Dagan, Israel, Division of Soil
Physics, Volcani Center.
Agronomy Journal, Vol. 66, No. 5, p 647-652, September-October, 1974. 9 fig,
1 tab, 16 ref, append.
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Descriptors: *Germination, *Seed treatment, Seeds, Soil aggregates, Soil-water-
plant relationships, Soil water, Moisture stress, Hydraulic conductivity.
Chickpea, pea and vetch seeds were germinated in pure, aerated water and in
sand or aggregate fractions of various grain-size classes. These were either 1)
packed in columns at various water contents kept constant by passing water at
different rates equaling the conductivity of the least conductive layer in
every column or 2) sown in aggregated soil at equilibrium with different
matric water potentials. Water uptake rates, seed diameter, and time of germi-
nation were determined, and seed-soil water contact area was calculated.
Water uptake data were analyzed to yield an approximation of the seed-soil water
contact impedance by using a simplified model. The results show that the seed-
soil water contact impedance increased as the wetted seed area and/or soil
hydraulic conductivity decreased. The data also show that for optimal seed-
soil water contact in aggregated soils, the mean aggregate size should be one-
fifth to one-tenth of the seed's diameter. Possible application to field prac-
tice, such as seed-bed preparation, is discussed.
74:03F-165
VARIATION IN EFFECTIVENESS OF SUPPLEMENTAL IRRIGATION ON SWEET CORN YIELD
COMPONENTS,
Andrew, R.H. and Weis, G.G.
Wisconsin University, Madison, Department of Agronomy.
Agronomy Journal, Vol. 66, No. 3, p 345-350, May-June, 1974. 1 fig, 7 tab,
14 ref.
Descriptors: *Supplemental irrigation, Crop response, Sweet corn, Irrigation
efficiency, Moisture availability, Moisture tension.
Supplemental irrigation is of increasing importance in the production of pro-
cessing sweet corn in the humid Midwest. However, wide variation exists for
efficiency of irrigation as related to uniformity and quality as well as
yield of this crop. The present study was planned to measure the response of
major sweet corn yield components to, and their interaction with, irrigation
level as related to genotype, plant competition, and season and to provide
guidelines for optimum production practice. Six hybrids were grown at three
populations (39,000, 49,000 and 59,000 plants/ha) under low and high irrigation
levels on droughty sand in central Wisconsin over a 9-year period. Measurements
were made of snapped weight, weight and number of usable husked ears, and
percent of usuable ears expressed on a weight and a number basis.
74:03F-166
CRESTED WHEATGRASS YIELDS AS INFLUENCED BY WATER CONSERVATION PRACTICES,
Bleak, A.T. and Keller, W.
United States Department of Agriculture, Agricultural Research Service, Logan,
Utah.
Agronomy Journal, Vol. 66, No. 2, p 326-328, March-April, 1974. 3 tab, 11 ref.
Descriptors: *Wheatgrasses, Crop response, Water conservation, Mulching,
Fertilization, Evaporation, Evaporation control.
Evaporation of water from the soil surface is a major economic loss to the
western United States, because water is the primary limiting factor in plant
growth on arid and semiarid rangelands. 'Nordan' crested wheatgrass was planted
in rows 1.1 m apart; the effect on total herbage yield of a gravel mulch, a
sheet metal "mulch," close rows of grass, and cereal grain seeded between
the grass rows was determined for a 2-year period. Some treatments received
different rates of N fertilizer. Sheet metal between the rows, covering 86%
of the land surface, increased mean 2-year yield about 112% over clean culti-
vation (check). A gravel mulch 1.5 cm deep increased mean yield about 16%.
Close rows of grass and cereal grain between the grass rows also increased total
yield. Benefit from nitrogen at 22, 44, or 66 kg/ha per year was minor.
Benefit from the mulches was greater the second year than the first.
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74:03F-167
EFFECT OF AN ASPHALT BARRIER ON WATER STORAGE AND DROUGHT PROBABILITY,
Palta, J.P. and Blake, G.R.
Minnesota University, St. Paul, Department of Soil Science.
Agronomy Journal, Vol. 66, No. 2, p 209-212, March-April, 1974. 3 fig, 2 tab,
7 ref.
Descriptors: *Asphalt, *Barriers, Droughts, Drought resistance, Available
water, Soil water, Soil water movement, Moisture availability, Moisture stress.
Field measurements of water redistribution after infiltration were made on
two sandy soils with and without asphalt barriers at a 55 cm depth to deter-
mine the barrier effect on soil water potential gradients and on water reten-
tion at various times. Estimates of the effect of the barrier on seasonal
drought severity and on movement of water to horizons below the barrier were
made on one of the soils. Soil water potential gradients and the volumetric
water content at different depths were nearly the same for barrier and non-
barrier plots on Hubbard loamy coarse sand because a coarse sand-gravel layer
between the 25 and 50-cm soil depths acts as a water barrier. After 96
hours drainage, suctions in Zimmerman fine sand reached 31 cm of water just
above the barrier and 61 cm at the same depth without barrier. Available
water to barrier depth was increased from 2.9 cm to 7.5 cm by the barrier.
74:03F-168
PERFORMANCE OF RICE VARIETIES IN A HIGHLY SALINE SODIC SOIL AS INFLUENCED BY
PLANT POPULATION,
Dargan, K.S., Abrol, I.P. and Bhumbla, D.R.
Central Soil Salinity Research Institute, Karnal, Haryana, India, Division of
Soils and Agronomy.
Agronomy Journal, Vol. 66, No. 2, p 279-280, March-April, 1974. 2 tab, 3 ref.
*Salinity, *Saline soil, *Crop response, *Rice, *Plant populations, Germination,
Alkalinity, Reclamation.
It is generally recognized that increased initial plant population or increased
seeding rate in saline sodic soils would compensate for decreased germination
and seeding mortality. However, there is little or no experimental evidence
of the gains obtained from such a practice. In present investigation, the
performance of seven rice varieties at three plant populations in a highly
saline sodic soil was studied in the field at the Central Soil Salinity
Research Institute, Karnal, India. Varieties tested were the tall indica
types 'Jhona 349', 'Jhona 351,' 'Basmati 217', and 'Basmati 370' and the semi-
dwarf types 'IR 8," 'IR6-681 and 'Jaya.' Plant populations used were 2, 4,
and 6 transplants/hill. Variety IR 8-68, a local selection from IR 8, with
6 transplants/hill gave the significantly highest grain yield at 57.33
quintals/ha. Variety IR 8 at 6 transplants/hill and Jhona 349 at 4 trans-
plants/hill yielded next in order. Increase in plant population from 2 to
4 and 6 transplants/hill resulted in significantly higher grain yield in
all varieties except Jhona 349 where there was a decrease at 6 transplants/
hill. Increased yield resulted from increased survival of hills and greater
number of panicle-bearing tillers per hill.
74:03F-169
EVAPOTRANSPIRATION BY SUBIRRIGATED ALFALFA AND PASTURE IN THE EAST CENTRAL
GREAT PLAINS,
Blad, B.L. and Rosenberg, N.J.
Nebraska University, Lincoln, Department of Horticulture and Forestry and
Conservation and Survey Division.
Agronomy Journal, Vol. 66, No. 2, p 248-252, March-April, 1974. 4 fig, 4 tab,
14 ref.
Descriptors: *Evapotranspiration, Subsurface irrigation, Alfalfa, Pastures,
irrigation practices, Irrigation, Nebraska, Latent heat, Advection, Energy
budget.
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Descriptors: *Evapotranspiration, Subsurface irrigation, Alfalfa, Pastures,
Irrigation practices, Irrigation, Nebraska, Latent heat, Advection, Energy
budget.
Evapotranspiration (ET) rates from subirrigated alfalfa pasture were obtained
to provide an estimation of the upper and lower limits of water demand for
crops growing in climatic regions characterized by strong advection of sensible
heat. Results of this study showed that ET rates were 20 to 25% lower in
pasture than in alfalfa. These differences are much larger than any previously
reported in the literature. Advected sensible heat supplied about 20% of the
total energy consumed in the latent heat flux (LE) from alfalfa for the entire
study and as much as 40% on certain days. In the pasture, however, with few
exceptions, sensible heat was generated rather than consumed.
74:03P-170
COMPARISON OF FOG IRRIGATION WITH SURFACE IRRIGATION IN CORN PRODUCTION,
Doss, B.D.
United States Department of Agriculture, Agricultural Research Service, Auburn,
Alabama.
Agronomy Journal, Vol. 66, No. 1, p 105-107, January-February, 1974. 3 tab,
8 ref.
Descriptors: *Mist irrigation, *Furrow irrigation, *Surface irrigation, Crop
response, Corn, Irrigation systems, Irrigation practices, Irrigation effects.
Water stress by plants during silking and ear development often affects the
yield of corn. Water stress sometimes occurs during midday even with a rela-
tively high soil water content. Field experiments were conducted for 3 years
to determine the effect of fogging or mist irrigation alone, surface irrigation
alone, and fogging plus surface irrigation on plant characteristics and grain
and stover yields of corn. Plants received mist irrigation daily from 1000 un-
til 1600 during silking and ear development. Surface irrigation was applied to
maintain soil water at or above the 50% available level (0.8 bar) in the sur-
face 60 cm of soil. An increase in grain yield was obtained in each of the
3 years with surface irrigation and in 2 of the 3 years with fogging or mist
irrigation, but fogging in addition to surface irrigation did not increase
grain yields above those for surface irrigation alone. Average grain yields for
the 3 years were 6,200, 8,400, 9,200, and 9,500 kg/ha for no irrigation,
fogging, surface, and fogging plus surface irrigation, respectively.
74:03F-171
CHOICE OF IRRIGATION TIMING INDICATOR FOR NARROW ROW COTTON,
Bordovsky, D.G., Jordan, W.R., Hiler, E.A., and Howell, T.A.
Kansas Agricultural Experiment Station, Colby Branch Station, Colby.
Agronomy Journal, Vol. 66, No. 1, p 88-91, January-February, 1974. 4 fig,
3 tab, 17 ref.
Descriptors: *Soil moisture, Soil-water-plant relationships, Water management,
Irrigation efficiency, Irrigation practices, Irrigation, Soil water potential.
This irrigation study was undertaken to compare water use efficiencies (WUE)
resulting from three methods of timing water applications on narrow-row cotton.
Irrigation timing during the 1971 and 1972 growing seasons was accomplished
using the soil water potential (SWP)- fixed level, leaf water potential (LWP)-
fixed level, and stress day index (SDI)-variable level of LWP, based on crop
sensitivities, as indicators. Specific levels of each indicator were selected
so that nearly identical yields would result for all three timing indicators,
thus making possible the valid comparison of WUE. With the SWP indicator as a
basis for comparison, higher WUE were obtained with the LWP and SDI indicators
in both years. At a plant population of 150,000 plants/ha average increases in
WUE (seed cotton yield divided by irrigation plus rainfall amounts) were 17
and 38% for the LWP and SDI indicators, respectively. These results demonstrate
that significant benefits in stretching irrigation water supplies are possible
when using plant-based measurements and when plant sensitivities at different
growth stages are quantitatively considered in timing irrigations.
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74:03F-172
EVALUATION OF AN OVER-EXTENDED SPRINKLER IRRIGATION SYSTEM,
Korven, H.C. and Wiens, J.K.
Canadian Society of Agricultural Engineers, Research Station, Swift Current,
Saskatchewan S9H 3X2.
Journal of Canadian Society of Agricultural Engineering, Vol. 16, No. 2,
p 51-57, December 1974. 4 fig, 6 tab, 7 ref.
Descriptors: *Sprinkler irrigation, Irrigation practices, Irrigation systems,
Evaluation, Consumptive use. Cost analysis.
Maximum production under irrigation requires a system with the capacity to meet
the peak water requirements of the plant. Surface irrigation systems, particu-
larly the border dyke method fed by gravity water, are designed and operated
so that elapsed time required to irrigate a field (irrigation cycle) is much
shorter than the elapsed time between irrigations (irrigation interval).
Sprinkler irrigation systems, however, are designed and operated so that most,
if not all, of the irrigation interval is used for the irrigation cycle. The
main reason for this is one of economics. The cost of the system is decreased
as more of the available irrigating time is used for irrigating. The purpose
of this study was to examine the yields and economic ramifications of using a
sprinkler irrigation system over a larger area than that determined by the nor-
mal criterion of designing the system to meet peak water requirements.
74:03F-173
THE RELATIONSHIP BETWEEN SOLAR RADIATION, SOIL WATER, AND WATER POTENTIAL OF
EARS OF WHEAT,
Dougherty, C.T.
Department of Plant Science, Lincoln College, Canterbury, New Zealand.
New Zealand Journal of Agricultural Research, Vol. 17, No. 4, p 459-463,
November 1974. 2 fig, 2 tab, 11 ref.
Descriptors: *Soil water, *Moisture tension, *Solar radiation, Wheat, Crop
Water potentials of ears of 'Kopara1 wheat grown in the field with or without
irrigation were measured by pressure bomb between 0900 and 1000 h and related
to soil water and solar radiation. Water potentials of ears from irrigated
wheat ranged from -2 to -14 bars, and from -8 to -27 bars in ears from non-
irrigated plots. Ear water potentials between 0900 and 1000 h were related to
soil water percentage and mean solar radiation received between 0700 and 0800 h.
74:03F-174
AN ANALYSIS OF A NITROGEN-INDUCED DEPRESSION OF YIELD IN IRRIGATED 'KOPARA1
WHEAT,
Dougherty, C.T. and Langer, R»H.M.
Department of Plant Science, Lincoln College, New Zealand.
New Zealand Journal of Agricultural Research, Vol. 17, No. 3, p 325-323, August
1974. 2 fig, 7 tab, 20 ref.
Descriptors: *Fertilization, *Fertilizers, Moisture tension, Nitrogen, Wheat,
Crop response, Plant growth.
Heavy applications of nitrogen fertilizer (200 kg/ha) applied in early spring to
wheat on a Wakanui silt loam, in which irrigation was used to maintain soil-
water levels above -0.5 bar, depressed grain yield by 30%. Poor grain set was
the main cause of the low yields, but mean grain weights were also reduced.
Analysis of data indicated that grain set was probably restricted by the
availability of carbohydrate during the critical pre-anthesis period of floret
development.
74:03F-17 5
EFFECTS OF IRRIGATION AND FERTILIZER ON THE YIELDS OF 'ARAWA1, 'AOTEA1, AND
'KARAMU1 WHEATS,
Dougherty, C.T., Scott, W.R., Langer, R.H.M. and Meijer, G.
Department of Plant Science, Lincoln College, Canterbury, New Zealand.
103
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New Zealand Journal of Agricultural Research, Vol. 17, No. 2, May 1974. 3 fig,
5 tab, 30 ref.
Descriptors: 'Fertilization, *Fertilizers, *Irrigation practices, Wheat,
Irrigation effects, Plant growth, Agronomic crops.
Grain yields of 'Aotea', 'Arawa', and 'Karamu1 wheats were depressed by irriga-
tion during early stages of reproductive development which reduced the number
of grains per spikelet and slowed the rate of reproductive development. Nitro-
gen fertilizer increased the ear population at harvest but had little effect on
the dry weight or leaf area of the tillers during the critical pre-anthesis
stage or on the mean values of the components of yield of the ears. There were
no interactions between fertilizer and irrigation treatments. 'Karamu1, a
Mexican semi-dwarf, was similar to the New Zealand-bred wheats except that it
had slightly more spiklelets per ear and grains per spikelet, but it had smaller
grains. An antitranspirant applied to irrigated wheat had no effect on any of
the components of grain or straw yield. Responses were interpreted on the basis
that pre-anthesis assimilate levels were modified by agronomic treatments and
affected grain set.
74:03F-176
PREDICTION OF PLANT RESPONSE TO FERTILIZERS BY MEANS OF SOIL TESTS,
Grigg, J.L. and Stephen, R.C.
Invermay Agricultural Research Centre and Field Research Section, Ministry of
Agriculture and Fisheries, Christchurch, New Zealand.
New Zealand Journal of Agricultural Research, Vol. 17, No. 1, p 31-40, February
1974. 1 fig, 7 tab, 15 ref.
Descriptors: *Fertilizers, *Fertilization, *Crop response, *Soil tests, Wheat,
Phosphate, Crop production, Plant growth.
Data from 82 rates-of-fertilizer trials on wheat, in which double superphosphate
was the source of phosphate, were used to evaluate the predictability of grain
yield responses from soil-test measurements. Yield data were reduced to single
values for correlations with soil phosphorus tests by calculating (a) relative
yields % and (b) the first principal components of the yield responses. Regres-
sion of these parameters on values from eight different soil tests, using a
quadratic model in the square root scale, showed that the Olsen soil test modi-
fied to 16-h extraction and a soil: solution ratio of 2.2 ml: 100 ml accounted
for more variation than other soil tests examined. The correlations with soil
tests were closer for the relative yields than for the first principal compo-
nents .
74:03F-177
WATER SHORTAGES AND AGRICULTURE: SOME RESPONSES,
Gates, C.T.
Division of Plant Industry, Canberra City, Australia.
The Journal of the Australian Institute of Agricultural Science, Vol. 40, No.
2, p. 121-142, June 1974. 13 fig, 3 tab, 62 ref.
Descriptors: *Water shortages, *Agriculture, *Australia, Crop response, Soil
water, Moisture tension, Fertilization, Root development.
Water shortages of varying intensities impose a prime limitation on Australian
agriculture, resulting not only in poor plant yield from droughting, but also
engendering such economic uncertainty that farmers restrict their programs.
However, this situation may be alleviated by practical consideration of certain
concepts which arise from existing fundamental knowledge. It is the purpose of
this article to bring together the diverse fields of knowledge containing prac-
tical information relevant to the problem of water shortage and by analyzing
them in sufficient detail reach some useful conclusions.
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74:03F-178
DRIPPER SPACINGS FOR UNIFORM IRRIGATION COVERAGE WITH CONTINUOUS TRICKLE
IRRIGATION,
Stevenson, D.S.
Agriculture Canada, Research Station, Summerland, B.C.
International Commission on Irrigation and Drainage, p 17 & 25, July 1974.
1 tab.
Descriptors: *Irrigation practices, *Irrigation design, *Irrigation efficiency,
Irrigation systems.
Trickle irrigation depends on a soil's ability to transfer water horizontally,
a radical departure from sprinkler technology which is based on uniform applica-
tion of water via the delivery equipment itself. It must be recognized that ap-
plication of all the water a plant uses each day to some arbitrary land area
somewhere around each plant, such as a tree or vine, will not produce uniform,
efficient and adequate irrigation except by chance. The lateral transfer of
water while it moves vertically in each soil must be the basis upon which appli-
cation per unit time per unit area is established.
74:03F-179
THE "MULTIVALVE" IRRIGATION METHOD,
Karamanos, A.J.
International Commission on Irrigation and Drainage, p 42-59, January 1974.
9 fig, 19 tab.
Descriptors: *Irrigation systems, *Irrigation engineering, Irrigation, Irriga-
tion practices, Crop response, Equipment.
The "multivalve irrigation" is a modification of the drip or trickle irrigation
method, which comprises the use of the "multivalve", first invented and described
by Mr. A.G. Petzetakis at the Seventh European Regional Conference of the
I.C.I«D* held at Aix-en-Provence in 1971. The "multivalve" is a bronze head
containing 32 capillary polyethylene tubes. The ends of each tube are put into
the soil at different spacings. The first experiment on this new irrigation
method was carried out during the summer period 1972. The purpose of the experi-
ment was to determine the most suitable distance for placing the tubes with
regard to the growth and productivity of the plants and to the financial aspect
of the method. The spacings used were 50 cm x 50 cm, 75 cm x 75 cm, 100 cm x
100 cm and 150 cm x 150 cm. At the same time the results of the multivalve
system were compared with those obtained from a control plot irrigated by
furrows.
74:03F-180
THE VALUE OF VEGETATION FOR CONSERVATION II. Ml MOTORWAY AREA,
Helliwell, D.R.
Merlewood Research Station, Grange-over-Sands, Lancashire, England.
Journal of Environmental Management, Vol. 2, No. 1, p 75-78, January 1974. 1
fig, 1 ref.
Descriptors: *Vegetation effects, Vegetation, Conservation, Plant populations.
A list of plant species occurring along 175 miles (282 km) of motorway embank-
ment has been used in an attempt to compare the conservation "value" of this
vegetation with four other areas of vegetation, but it is concluded that such
a comparison is not possible.
74:03F-181
THE VALUE OF VEGETATION FOR CONSERVATION I. FOUR LAND AREAS IN BRITAIN,
Helliwell, D.R.
Merlewood Research Station, Grange-over-Sands, Lancashire, England.
journal of Environmental Management, Vol. 2, No. 1, p 51-74, January 1974.
1 fig/ 4 tab, 5 ref, 1 append.
Descriptors: *Vegetation effects, Vegetation, Conservation, Plant population
105
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Lists of plant species and their relative frequency have been used, in conjunc-
tion with the "Atlas of the British Flora", to compare the conservation "value"
of the vegetation on four different areas of land in Britain. A wide range of
assumptions as to the weighting to be given to the rarity of species gives
very similar results in each case.
74:03F-182
EFFECTS OF TIME TAKEN TO APPLY AN IRRIGATION ON SEASONAL IRRIGATION REQUIREMENTS,
Sly, W.K. and Wilcox, J.C.
Chemistry and Biology Research Institute, Canada Department of Agriculture,
Ottawa, Canada.
Journal of the Canadian Society of Agricultural Engineering, Vol. 16, No. 2,
p. 82-85, December 1974. 3 tab, 11 ref.
Descriptors: *Scheduling, Irrigation practices, Consumptive use, Irrigation
systems, Timing, Canada, Soil water, Water consumption.
Daily climatic data for the 30 year period 1931-60 were used in two routine
scheduling procedures to estimate seasonal irrigation requirements for soils
of different water-holding capacities at six selected localities in British
Columbia. The first procedure, described in detail by Wilcox and Sly, closely
follows the practices recommended for the Okanagan Valley. Four days are
required to apply each 2.54 centimeters of water to the field. In the second
procedure, equipment was assumed to be such that water would be applied to the
entire field at the same time. The same basic principles are followed as with
the first procedure, but adjustments were made to ensure that the same avail-
ability of soil water to plants prevailed under both methods. Differences in
the irrigation requirements resulted from these adjustments. In every case, .
and for each water-holding capacity of the soil and each climatic condition,
less water was required under the second scheduling method.
74:03F-183
NITRATE UPTAKE EFFECTIVENESS OF FOUR PLANT SPECIES,
Warncke, D.D. and Barber, S.A.
Purdue University, West Lafayette, Indiana.
Journal of Environmental Quality, Vol. 3, No. 1, p 28-30, January-March, 1974.
2 tab, 5 ref.
Descriptors: *Fertilization, *Fertilizers, *Nitrogen, Crop response, Plant
growth, Corn, Soybeans, Bromegrass, Nitrates.
Little information is available on the characteristics of plant roots that
determine their effectiveness in nitrate uptake. The effectiveness of nitrate
uptake of corn, soybeans, sorghum, and bromegrass intact roots were investigated
in nutrient solution culture. The maximum uptake rate per centimeter of root
for corn occurred at 10 mM, for sorghum at 2.4 mM, and for bromegrass at 0.8 mM.
Increasing the nitrate level above 1.0 mM did not increase the growth rate dur-
ing the first 3 weeks for any of these species. The results of this research
indicate that the roots of the species investigated absorbed nitrate of maximum
rates from relatively low nitrate concentrations provided the concentration was
maintained. Also, the degree of reduction in nitrate level where nitrate in
solution was not maintained indicated that these plant roots had the absorptive
capacity to reduce solution nitrate to concentrations of 4 micro-M or less.
74:03F-184
NITROGEN-15 VARIATIONS IN FERTILIZER NITROGEN,
Freyer, H.D. and Aly, A.I.M.
Institute of Physical Chemistry, Nuclear Research Center Juelich, Federal
Republic of Germany.
Journal of Environmental Quality, Vol. 3, No. 4, p 405-406, October-December,
1974. 1 tab, 11 ref.
Descriptors: *Fertilizers, *Nitrogen, *Ammonium compounds.
106
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Nitrogen-15 concentrations of some commonly used nitrogen fertilizers are
measured. Ammonium-nitrogen has lower and nitrate-nitrogen has higher 15(N)
concentrations than atmospheric nitrogen.
107
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Section XIII
WATER QUANTITY MANAGEMENT AND CONTROL
CONTROL OF WATER ON THE SURFACE (Group 04A)
74:04A-001
DRAINAGE SYSTEM DESIGN AND ANALYSIS BY COMPUTER,
Rentier, D.M. and Mueller, C.C.
Soil Conservation Service, Portland, Oregon.
Journal of the Irrigation and Drainage Division, American Society of civil
Engineers, Vol. 100, No. IRS, Proceedings paper No. 10801, p 255-265, September
1974. 8 fig, 1 tab, 11 ref.
Descriptors: *Drainage systems, *Subsurface drainage, *Design, *Computer pro-
grams, *Equations, *Irrigated land, Tile drains,'Water table, Costs, Depth,
Hydraulic conductivity, Washington, Systems analysis.
The conditions needed for the theoretical mathematical solution in the design
of subsurface drainage systems are usually hard to find in the field. An opti-
mum system design cannot be obtained without knowledge of the correct inputs to
the drainage design equation. Two programs are presented for using the com-
puter to design subsurface' drainage systems for irrigated areas. The first
calculates drain spacings using the Dumm, Moody, and Tapp nonsteady-state
transient flow method, which provides close correlation between theory and
practice. The second program provides drainage system layouts in an area re-
quiring drainage for any specified drain spacing and drain depth. Using these
two programs, all input parameters can be investigated and the effect of their
variance on both drain spacing and system cost can be found. Thus, a sensi-
tivity relationship between the drain spacing and system layout, and the para-
meters used in calculating the spacing, can be defined.
74:04A-002
OPTIMAL CONTROL OP MULTIUNIT INTER-BASIN WATER RESOURCE SYSTEMS,
Takeuchi, K. and Moreau, D.H.
Tokyo Institute of Technology, Japan, Department of Civil Engineering.
Water Resources Research, Vol. 10, No. 3, p 407-414, June 1974. 6 fig, 2 tab,
28 ref.
Descriptors: *Multiple-purpose projects, *River basin development, *Reservoir
operation, *Linear programming, *Dynamic programming, Stochastic processes,
Algorithms, Simulation analysis, Equations, Optimization, Economic efficiency,
Reservoir storage, Reservoir releases, Inflow, Streamflow, Methodology, Decision
making, North Carolina, Mathematical models, Systems analysis.
A method is presented for finding optimal operating policies for a multi-
reservoir water resource system that extends over two river basins and serves
multiple demands. The method has been developed and tested for one of several
water resource systems proposed for further development in the urbanizing Pied-
mont Triad region of North Carolina. Monthly operating decisions are given by
solutions of a piecewise linear programming problem; the objective function
consists of two parts: immediate economic losses within the month and the
expected present value of future losses as a function of end-of-month storage
levels in the reservoirs. The latter function is estimated by imbedding the
linear programming problem in a stochastic dynamic programming problem. An
approximate solution technique for the larger problem is described, and com-
putational experience is reported. The approximate solution technique involves
the use of simulation in a recursive algorithm. Simulation is used also to
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test the derived policy on the 40 years of actual streamflow data that exist
in the case study area.
74:04A-003
OPTIMAL DESIGN AND OPERATION OF WATER DISTRIBUTION SYSTEMS,
Shamir, U.
Thomas J. Watson Research Center, Yorktown Heights, New York.
Water Resources Research, Vol. 10, No. 1, p 27-36, February 1974. 1 fig, 2
tab, 31 ref.
Descriptors: *Water distribution(Applied), *Design, *Operation and maintenance,
*Methodology, Economics, Constraints, Performance, Physical properties. Opti-
mization, Pipes, Flow, Reservoirs, Water levels, Hydraulics, Costs, Computer
programs. Mathematical models, Systems analysis. Equation.
A methodology is developed for optimal design and/or operation of a water
distribution system that is to operate under one or several loading conditions.
Decision variables may be design variables, such as pipe diameters, or control
variables, such as heads and flows. The general formulation considers the
cost of the design and the cost of operating the system. The objective function
may include the initial cost of the design, the cost of operation, the physical .
measures of performance, and the penalties for violating constraints. Con-
straints may be imposed on the decision variables and on the performance of
the system under each loading. The model for the flow problem is based on
node equations. Flow solutions are obtained by a modified Newton-Raphson
method employing sparse matrix techniques. Optimization is obtained by a
combination of the generalized reduced gradient and penalty methods. Imple-
mentation in a computer program and its use on a test problem in both batch
and time-sharing modes are described, and it is concluded that the method is
computationally feasible. The many different ways in which it can be used
to analyze, design and operate water distribution systems are outlined.
74:04A-004
MODIFICATION OF ROUTED STREAMFLOW BY CHANNEL LOSS AND BASE FLOW,
Moench, A.F., Sauer, V.B. and Jennings, M.E.
Geological Survey, Denver, Colorado.
Water Resources Research, Vol. 10, No. 5, p 963-968, October 1974. 8 fig, 1
tab, 17 ref.
Descriptors: *Routing, *Base flow, *Water loss, *Hydrograph analysis, Computer
programs, Mathematical models, *Oklahoma, Surface-groundwater relationships,
Open channel flow, Stage-discharge relations.
The convolution integral was used to compute continuous variations in channel
loss and base flow that result from a reservoir release on the North Canadian
River in central Oklahoma. The open channel flow hydrograph was routed by
using the unit response method and then modified for interaction with the
aquifer. Stream losses and gains were evaluated from the arbitrary fluctuations
in stream stage by using average values of aquifer parameters. In spite of
gross simplification pertaining to the nature of the groundwater system, good
agreement with the actual flow hydrograph was obtained.
74:04A-005
EFFECTS OF INUNDATION PERIOD ON SEEDLING GROWTH,
Howell, T.A. and Hiler, E.A.
Texas A&M University, College Station, Agricultural Engineering Department.
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Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
p 286-288 & 294, March-April 1974. 5 fig, 1 tab, 11 ref.
Descriptors: *Drainage effects, *Drainage practices, Drainage, Crop response,
Corn, Cotton, Grain sorghum, Lysimeters, Aeration.
In considering the necessary steps for proper agricultural drainage design, the
logical first step is the determination of the crop's drainage requirement.
The purpose of this paper was to present and evaluate findings concerning
effects of inundation period on soil oxygen diffusion rates and crop response
during the seedling growth of four selected plant species. Corn, cotton, grain
sorghum, and southern pea plants were grown for 30 days in field lysimeters
which were inundated for periods of 2, 5, and 8 days, starting approximately
1 week after emergence. Undisturbed soil cores which were 90 cm in diameter
and 180 cm deep made up the lysimeters. Rainfall was kept off the lysimeters
with an automated shelter system. Oxygen diffusion rate and soil water
pressure potential measurements were made in the crop root zone on a regular
basis. Primary crop response measurements included crop height during the
growing season and dry matter yield at the end of the growth period. Water was
added at the soil surface to maintain the soil water pressure potential in the
crop root zone between -10 and - 20 centibars, and hence prevent crop water
stress, during periods when no flooding occurred.
74:04A-006
USB OF DRAINAGE WELLS,
Ham, H.H.
Bureau of Reclamation, U.S. Department of the Interior, Denver, Colorado.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 8 fig, 12 ref.
Descriptors: *Drainage wells. Drainage systems, Drainage practices. Drainage
engineering. Flow systems, Transmissivity.
Wells are often viewed as an alternative to drains for agricultural subsurface
drainage. Where subsurface and other conditions are favorable, wells may offer
advantages despite hydraulic and other shortcomings. However, areas of such
favorable conditions are limited. Furthermore, improper use of wells may
jeopardize long-term productivity of the land. Use of wells for agricultural
subsurface drainage may appear advantageous but should be approached with
caution unless investigations have determined that conditions are favorable.
74:04A-007
THE FATE OF NITRATE IN LAKE SEDIMENT COLUMNS,
Chen, R.L. and Keeney, D.R.
Wisconsin University, Madison, Department of Soil Science.
Water Resources Bulletin, Vol. 10, No. 6, p 1162-1172, December, 1974.
Descriptors: Sedimentation, Nitrogen cycle, Nitrogen, Denitrification, Seepage,
Oxidation-reduction potential.
To investigate the magnitude of denitrification and assimilatory nitrate
reduction as these reactions relate to the fate of nitrate reaching sediments
via groundwater seepage, undisturbed core samples of sediments (40 cm length)
from two lakes (Mendota and Tomahawk) were leached from the bottom (at 1.4 cm/
day) with a solution of 15N-nitrate (10 mg N/liter). The sediment columns
were fitted with Pt electrodes to measure the oxidation-reduction (Eh) potential.
While leaching removed considerable ammonium-N and soluble organic N, essentially
no 15N had passed through the columns by 50 days. The Eh readings indicated
that denitrification was occurring in the lower portions of the columns. The
15N distribution of the sediment N after 50 days showed that about 15 to 26% of
the added nitrate-N was converted to organic N and ammonium N. The data show
that denitrification can be a significant N sink in seepage lakes.
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74:04A-008
IRRIGATION IN THE UNITED STATES; THE SITUATION TODAY,
Warme, W.E.
International Commission on Irrigation and Drainage, p 12-16, July 1974.
Descriptors: Irrigation, Irrigation effects, Irrigation programs, Agriculture,
United States.
Irrigation supports the agriculture of the semi-arid and arid western United
States. Agriculture is the cominant industry of the region. Irrigation is
practiced increasingly in the more humid states, as well, but among them, except
in Florida, Arkansas and Louisiana, irrigation is not given much attention
as a factor influencing farm production. The situation in the United States
today is that irrigation is a western operation of critical importance in the
production of food and fiber. Irrigated agriculture is the foundation of the
economy of the western states.
74:04A-009
HYDROCHEMISTRY OF THE ATHABASCA AND NORTH SASKATCHEWAN RIVERS IN THE ROCKY
MOUNTAINS OF CANADA,
Drake, J.J. and Ford, D.C.
McGill University, Montreal, Quebec, Canada, Department of Geography.
Water Resources Research, Vol. 10, No. 6, p 1192-1198, December 1974. 4 fig,
3 tab, 12 ref.
(See 74:02E-003)
74:04A-010
SIMULATION OF GAMMA-DISTRIBUTED FIRST-ORDER MARKOV CHAIN,
Klemes, V. and Doruvka, L.
Hydrology Research Division, Ottowa, Ontario, Canada, Department of the
Environment.
Water Resources Research, Vol. 10, No. 1, p 87-91, February, 1974. 1 fig, 1
tab, 9 ref.
Descriptors: *Markov processes, Simulation analysis, Hydrology, Mathematical
studies, Mathematics.
Simulation of a serially correlated series with a given marginal distribution
is one of the important prerequisites of synthetic hydrology and of its appli-
cations to analysis of water resource systems. The problem has, however, no
fully satisfactory solution because of the difficulties in defining other
than normal multivariate distributions. The gamma-distributed first-order
Markov chain (TIMC) is one of the most useful models of this category, since
marginal distributions of many hydrologic variables can be approximated
satisfactorily by the gamma distribution, and the limited understanding of
the sequential behavior of the process combined with the smallness of available
data samples often does not warrant models more sophisticated than the first-
order Markov chain.
74:04A-011
AGRICULTURAL WASTE MANAGEMENT,
Committee on Agricultural Waste Management of the Environmental Engineering
Division.
journal of the Environmental Engineering-Division, Vol. 100, No. EE1, p 1-6,
February, 1974. 1 fig.
Descriptors: *Return flow, *Waste water (pollution), Wastes, Agriculture,
irrigation, Irrigation practices, Irrigation effects.
Since the practice of irrigation has detrimental effects on water quality, irri-
gation return flows must be considered an agricultural waste. The major water
quality problem is increased salt concentration in the return flows as a
result of the pickup of minerals from the soils and the loss of water through
evapotranspiration. Irrigated agriculture is the largest consumer of our water
resources, and return flows constitute a large portion of the flow in many
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western streams. Salt concentrated by evapotranspiration must be leached
from the root zone to continue crop production. This necessity of leaching to
maintain a salt balance concentrates salts in the return flows and causes
damage downstream.
74:04A-012
EVALUATION OF SURFACE WATER RESOURCES FROM MACHINE-PROCESSING OF ERTS
MULTISPECTRAL DATA,
Mausel, P.W., Todd, W.J., Baumgardner, M.F., Mitchell, R.A., and Cook, J.P.
Indiana State University, Terre Haute
Journal of Environmental Quality, Vol. 3, No. 4, p 316-321, October-December,
1974. 5 fig, 1 tab.
(See 74:078-008)
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Section XIV
WATER QUANTITY MANAGEMENT AND CONTROL
GROUNDWATER MANAGEMENT (Group 04B)
74:04B-001
EXTENSIVE PUMPING FROM UNCONFINED AQUIFERS,
Rushton, K.R.
Birmingham University, England, Department of Civil Engineering.
Water Resources Bulletin, Vol. 10, No. 1, p 32-41, February 1974. 5 fig, 2
tab, 5 ref.
Descriptors: Water resources development, *Water yield, *Groundwater movement,
^Numerical analysis, Drawdown, ^Withdrawal, Mathematical models, Water table,
Recharge, *Pumping.
Heavy pumping of an aquifer to remove a significant proportion of the stored
water is considered using a numerical method which permits the analysis of
radial flow to a well in an unconfined aquifer and allows for the reduction in
the saturated depth. The analysis is restricted to extensive unconfined
aquifers of constant thickness which are initially full of water with wells
positioned on a square grid. When the aquifer is recharged with the recharge
equaling the discharge, it is possible that a steady state will be reached with
the heads remaining constant with time. Withdrawal of a large proportion of
the available water from an unconfined aquifer requires carefully controlled
pumping. If the discharge rate is too high, the pump will quickly run dry and
only a very small proportion of the water will be withdrawn.
74:048-002
ANALYTICAL MODEL FOR MANAGEMENT OF ALLUVIAL AQUIFERS,
Qazi, R. and Danielson, J.
Colorado Department of Natural Resources, Denver, Division of Water Resources,
planning and Investigations.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR2, Paper no 10627, p 143-152, June 1974. 5 fig, 1
tab, 4 ref.
Descriptors: *Alluvial aquifers, *Wells, *Pumping, *Water management(Applied),
^Simulation analysis, *Computer models, Groundwater, Flow, Water table. Res-
ervoir storage, Recharge, Rivers, Surface waters, Conjunctive use, Water
delivery. Water supply, Damages, Drawdown, Canals, Irrigation water, Municipal
water, Computer programs, Equations, Evaluation, Systems analysis, ^Colorado.
Under the doctrine of prior appropriation, the recent inclusion of wells in
the existing priority system of water rights in Colorado has created new prob-
lems for water management in tributary alluvial aquifers. Irrigation and munic-
ipal wells, generally subordinate to surface water rights on a river, are sub-
ject to complete shut down if they cannot compensate for the river depletion
due to pumping; to shut these wells off could mean economic disaster to large
rural areas in Colorado. Therefore, augmentation plans have been accepted
by the Division of Water Resources whereby well owners must provide for river
depletion in both time and space either by recharge operations or by direct
deliveries to the river from acquired surface water. To evaluate these plans,
an analytical approach using computer simulation has been derived to estimate
the change in storage of the groundwater and the rate and amount of movement
of water to and from the river. The model, presented in detail, can provide
quick estimates of the volumetric movements and the fluctuation of the water
table due to any combination of wells, recharge lines, or pit operations in an
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alluvial (unconfined) aquifer. Model applications to the South Platte River
in Colorado, and results, are discussed. Compared to other conjunctive use
models, this does not require voluminous amounts of input data.
74:048-003
MULTILEVEL OPTIMIZATION FOR CONJUNCTIVE USE OF GROUNDWATER AND SURFACE WATER,
Yu, W. and Haimes, Y.Y.
Case Western Reserve University, Cleveland, Ohio, Systems Research Center.
Water Resources Research, Vol. 10, No. 4, p 625-636, August 1974. 7 fig, 6
tab, 22 ref, 2 append.
Descriptors: *Conjunctive use, *Systems analysis, *Optimization, Groundwater
resources, Surface waters, Water resources, Municipal water, Recharge, Im-
ported water, Irrigation water, Industrial water.
A general systems analysis approach, not using straight simulation methods, was
applied to the problem of optimal conjunctive use of groundwater, local sur-
face water, and imported water resources. A water resources management problem
was considered for a hypothetical region composed of several adjoining sub-
regions overlying a common aquifer. The aquifer was represented by a two-
dimensional asymmetrical grid network model. Local water agencies had ex-
clusive rights for developing and controlling all water resources in its sub-
region. Water demands for each subregion were classified as agricultural or
municipaleindustrial. A regional water authority optimally regulated the
region's water resources by establishing intersubregional aquifer boundary
conditions, and by imposing a pumping tax to pay the cost of recharging the
aquifer. The solution was implemented by a completely decentralized decision
making structure of two level hierarchy.
74:04B-004
ISOTOPIC AND CHEMICAL CHARACTERISTICS OF HIGH-LEVEL GROUNDWATER ON OAHU,
HAWAII,
Hufen, T.H., Buddemeier, R.W. and Lau, L.S.
Hawaii University, Honolulu, Water Resources Research Center.
Water Resources Research, Vol. 10, No. 2, p 366-370, April 1974. 4 fig, 2
tab, 18 ref.
Descriptors: *Groundwater, *Geohydrology, ^Radiocarbon, Tritium, Tunnels, Soil,
Isotopes, Chemistry, *Hawaii, *Chemical properties.
High level dike-confined groundwaters and high-level perched groundwaters on
Oahu, Hawaii, were analyzed for tritium, radiocarbon, carbon 13, and several
chemical constituents. Discharges from several tunnels that tap dike compart-
ments contain postbomb tritium, indicating the presence of modern (since 1954)
recharge. The amount of this recharge in samples taken inside one of the tun-
nels is a function of the distance between overlying surface and sampling point.
Chemical and carbon isotopic compositions of dike waters, established in the
soil zone of their overlying ground surface, remain unchanged while the water
is passing through the basaltic carbonate-free compartments. Dike water carbon
isotope data are sufficiently consistent to serve as initial values for the
dating of water in the Honolulu basal aquifers. The radiocarbon data suggest
that the maximum value for residence of the dike waters is of the order of 100
years.
74:04B-005
THE OPERATION OF A STREAM-AQUIFER SYSTEM UNDER STOCHASTIC DEMANDS,
Maddock, T., III
114
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Geological Survey, Reston, Virginia.
Water Resources Research, Vol. 10, No. 1, p 1-10, February 1974. 2 fig, 5 tab,
19 ref.
Descriptors: "Conjunctive use, "Stochastic processes, Statistical methods,
*Water demand, Water yield, *Surface-groundwater relationships, Artificial
recharge. Drawdown, Withdrawal.
It is possible to develop operating rules for the conjunctive use of surface
water and groundwater when the demand and supply sources are stochastic.
These rules allow the quantities of water pumped from wells, diverted from
streams, spread, and returned to the stream after use to be determined for a
given time period even if the required needs and availability of supply are
uncertain at the beginning of the time period. These rules are dependent on
a technological function relating streamflow interaction with well pumping and
with the statistics of the demands, streamflow, pumping, and drawdowns. The
discounted expected cost and the operating rules are functions of not only the
expected value of the demands but also its variance and persistence (as measured
by an autocorrelation function). The discounted expected cost has high sensi-
tivity to demand variances and some sensitivity to persistence.
74:048-006
GROUNDWATER MANAGEMENT AND SALINITY CONTROL,
Cummings, R.G. and McFarland, J.W.
Rhode Island University, Kingston, Department of Resource Economics.
Water Resources Research, Vol. 10, No. 5, p 909-915, October 1974. 37 ref.
Descriptors: *Groundwater resources, "Management, "Salinity, "Irrigation,
"Water quality control, Analytical techniques, Methodology, Mathematical models,
Water utilization, Taxes, Downstream, Equations, Economics, Agriculture, Water
supply/ Leaching, Soil moisture, Capital, Economic efficiency, Costs, Benefits,
Systems analysis, Optimization.
Presented is an analytical framework for an integrated approach to the water-
salinity management problem. The framework recognizes (1) the intertemporal
problem of endogenously determined water scarcity and the ramifications of
such scarcity for the opportunity cost of water used for leaching purposes,
and (2) optimal investment rates for capital and the role of capital in re-
ducing salinity as well as in 'saving1 scarce water supplies. A mathematical
model is presented that may be useful in analyzing decision rules for the con-
junctive management of groundwater reserves for use in irrigation and salinity
control. Policy implications of this approach are examined, particularly as
they relate to the difficulties associated with the use of economic incentives
for the purpose of bringing about optimal water use patterns in a decentralized
decision-making government. Alternative schemes for decentralized management
via taxes and bribes are discussed. Taxes are described that bring about intra-
district efficiency in terms of use and salinity control when downstream ex-
ternalities are ignored. When externalities are considered, it is shown that
unique pattern of resource use requires a given institutional structure for
the management of bribes.
74:048-007
GROUND-WATER RECHARGE STRIP BASIN-EXPERIMENTS,
nrock/ R«R« snd Amar, A.C.
ralifornia State University, Fullerton, Department of Civil Engineering
Tournal of the Hydraulics Division, American Society of Civil Engineers Vol 100,
No HY4, Paper 10503, p 569-592, April 1974. 12 fig, 2 tab, 15 ref, append
115
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Descriptors: *Artificial recharge, *Groundwater recharge, *Hydraulic models,
*Dupuit-Forchheimer theory, Porous media, Groundwater movement, Unsteady flow.
The problem of recharging a strip basin to a horizontal water table overlying
an impervious base was formulated using the saturated flow equations. From
this formulation the number of dimensionless variables that determine a
dimensionless water table rise were identified using the exact or potential
theory and an approximate (Dupuit-Forchheimer) theory. Experiments were
performed in a 5-m long sand model. As a dimensionless recharge rate was
increased, an expected systematic deviation from the theory is presumably
a result of the invalidity of the assumption of the theory for deep flows.
Experimental results are presented in the form of dimensionless graphs.
74:048-008
SALINITY MANAGEMENT FOR HIGH FREQUENCY IRRIGATION,
Hoffman, G.J., Rawlins, S.L., Oster, J.D., and Merrill, S.D.
United States Department of Agriculture, Riverside, California.
Proceedings of the Second International Drip Irrigation Congress, pp. 372-375,
July 1974. 4 fig.
Descriptors: *Salinity, *Saline soil, *Saline water, *Leaching, Grain sorghum,
Lettuce, Wheat, Crop response, Irrigation practices, Irrigation, Agriculture.
A field plot experiment designed to determine the minimum leaching required to
maintain crop yields under high frequency irrigation is described. Two
varieties of wheat, grain sorghum, and lettuce are being grown in rotation
each year in six replicated leaching fraction treatments. Precise measurements
of the volume and salt concentration of the irrigation and drainage waters
along with in-situ soil salinity measurements and crop yield are reported.
74:04B-009
IRRIGATION RETURN FLOW AS INFLUENCED BY DRIP IRRIGATION,
Patterson, T.C. and Wierenga, P.J.
New Mexico State University, Las Cruces, New Mexico.
Proceedings of the Second International Drip Irrigation Congress, pp. 376-381,
July 1974. 2 fig, 3 tab, 4 ref.
Descriptors: *Return flow, *Water quality, *Salinity, *Surface irrigation,
*Saline water, *Saline soil, New Mexico, Texas, Irrigation practices, Irrigation
systems, Irrigation, Agriculture.
Deterioration of water quality in the Rio Grande is a major problem for water
users in New Mexico and Texas. From near Santa Fe, New Mexico to El Paso,
Texas, a distance of 270 miles, the total of dissolved solids increases from
221 ppm to 787 ppm while the percent of sodium increases from .25 near Santa Fe
to 52 at El Paso. The deterioration in quality is due to the return of lower
quality drainage water from the irrigated areas to the river. This paper
describes a project designed to determine, under field conditions, rates of
water and salt movement in the soil and subsequently to the drains as affected
by frequency and amount of trickle irrigation, as compared to frequency and
amount of surface water application. Both return flow quality and quantity
are evaluated.
74:04B-010
SOIL SALINITY DISTRIBUTION IN SPRINKLER-AND SUBSURFACE-IRRIGATED CITRUS,
Nelson, S.D. and Davis, S.
Brigham Young University, Prove, Utah.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 1,
p 140-143, January-February 1974. 4 fig, 3 tab, 4 ref. .
Descriptors: *Saline soil, *Salinity, *Sprinkler irrigation, *Subsurface
irrigation, *Citrus fruits, Leaching, Irrigation practices. Irrigation effects,
116
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Irrigation systems, Irrigation, Agriculture.
Soil salinity distribution produced by subsurface irrigation results in
maximum salt concentrations at the perimeter of the wetting front. The soil
salinity increases most in the soil above the burial depth of the subsurface
pipe. Winter rainfall could be effectively used to leach accumulated surface
salts from the root zone of subsurface - irrigated citrus in southern Cali-
fornia, by maintaining a high water content during the rainfall months, allowing
precipitation to be used only for leaching and not for increasing the soil
water content. By using this management method, a more favorable salt balance
was maintained.
74:048-011
FIELD LEACHING BY SPRINKLER AND SURFACE IRRIGATION DURING A CROP SEASON,
Hermsmeier, L.F. and Kaddah, M.T.
Imperial Valley Conservation Research Center, Brawley, California.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
p 275-279, March-April 1974. 4 fig, 5 tab, 1 ref.
Descriptors: *Leaching, Sprinkler irrigation, Surface irrigation, Salinity,
Irrigation practices, Irrigation effects, Irrigation operation and management,
Irrigation water, Barley, Crop production, Irrigation, Agriculture.
Applying excess irrigation water to a winter barley crop can be used to leach
salt from the soil at the same time crop production is proceeding. Surface
irrigation and sprinkler irrigation were equally effective in leaching salt
from the soil during a barley season. Application of more water between the
drains than near the drains with sprinklers improved but slightly the salt
removal between the drains in the top foot of soil and gave no greater improve-
ment at a depth of 4 to 5 feet. Application of 30% excess water with surface
irrigation and 67% excess water with sprinklers produces good barley yields.
74:048-012
CRITICAL STATE OF SALT-WATER UPCONING BENEATH ARTESIAN DISCHARGE WELLS,
Streltsova, T.D. and Kashef, A-A.I.
Birmingham University, England, Department of Civil Engineering.
Water Resources Bulletin, Vol. 10, No. 5, p 995-1008, October, 1974. 4 fig,
1 tab, 10 ref.
Descriptors: Artesian aquifers, Artesian wells, Groundwater, Pumping, Saline
water intrusion, Saline water-freshwater interfaces, Water resources, Free
surfaced, Model studies.
An approach, based on the realization of the vertical components of flow is
presented to determine the free surface of gravity wells and the shape of salt-
water upcoming in artesian aquifers. The transitional stages from pumping fresh
water to pumping salt water at the critical condition are discussed. Vertical
hydraulic resistances, being determined and included in the flow domain, allow
the use of the finite-difference approximation in a simple form. The suggested
approach implies the use of either simple modeling or computing techniques.
74:048-013
AN EVALUATION OF KINETIC AND EQUILIBRIUM EQUATIONS FOR THE PREDICTION OF PESTI-
CIDE MOVEMENT THROUGH POROUS MEDIA,
van Genuchten, M. Th., Davidson, J.M., Wierenga, P.J.
jjew Mexico State University.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 29-35, January-
February, 1974. 7 fig, 2 tab, 18 ref.
Descriptors: Herbicides, Adsorption, Simulation analysis, Model studies, Soil
water movement, Pesticides, Pollutants.
jliscible displacement techniques were used to study the movement of picloram
(4-amino-3,5, 6-trichloropicolinic acid) through a water-saturated Norge loam
soil« Tne equilibrium adsorption and desorption isotherms for picloram and
117
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Norge loam soil were not single-valued relations. Picloram movility was reduced
significantly when the average pore-water velocity was decreased from 145 to
14.2 cm/day. Observed and predicted effluent concentration distributions were
compared. Predictions were made with a S/360 CSMP simulation model, using two
kinetic rate equations and an equilibrium Freundlich equation.
74:048-014
UNSATURATED HYDRAULIC CONDUCTIVITY FROM CUMULATIVE INFLOW DATA,
Ahuja, L.R.
Hawaii University, Honolulu, Department of Agronomy and Soil Science.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 695-699,
September-October, 1974. 6 fig, 13 ref.
(See 74:02G-024)
74:048-015
STEADY FLOWS OF WATER AND SALT IN UNIFORM SOIL PROFILES WITH PLANT ROOTS,
Raats, P.A.C.
U.S. Salinity Laboratory, Riverside, California.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 717-722,
September-October, 1974. 8 fig, 20 ref.
(See 74:020-025)
74:048-016
TWO-DIMENSIONAL DISPLACEMENT INTO OR FROM WATER-FILLED DITCHES,
Miyamoto, S. and Warrick, A.W.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 723-726,
September-October, 1974. 5 fig, 1 tab, 11 ref, append.
(See 74:02G-026)
74:048-017
CHLORIDE AND TRITIATED WATER FLOW IN DISTURBED AND UNDISTURBED SOIL CORES,
McMahon, M.A. and Thomas, G.W.
Kentucky University, Lexington, Department of Agronomy.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 727-732,
September-October, 1974. 6 fig, 4 tab, 13 ref.
(See 74:02G-027)
74:04B-018
ASSESSING SOIL SALINITY AND IDENTIFYING POTENTIAL SALINE-SEEP AREAS WITH FIELD
SOIL RESISTANCE MEASUREMENTS,
Halvorson, A.D. and Rhoades, J.D.
United States Department of Agriculture, Agricultural Research Service, Sidney,
Montana.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 576-581,
July-August, 1974. 7 fig, 4 tab, 12 ref.
Descriptors: *Soil salinity, *Salinity, *Soil tests, Soil properties, Elec-
trical conductance.
The recent widespread increase in the occurrence of seep areas high in salinity
in the northern Great Plains has increased the need for soil salinity research.
The objective of the study was to examine the use of soil conductivity values
calculated from resistance measurements obtained with the four-probe Wenner
electrode configuration to identify potential saline-seep areas and estimate
soil salinity in the field. Plots of apparent soil conductivity (EC) vs inner-
electrode spacing (a) yielded different types of curves for saline-seep areas,
recharge areas, and intermediate areas. Plots of EC vs a or EC values alone
can be used to identify potential saline-seep areas. Significant correlations
were obtained in May (r=0.98) and August (r=0.96) between apparent soil conduc-
tivity (EC) and electrical conductivity of saturation extracts showing that
four-probe soil resistance measurements can also be used to estimate soil
salinity in the field.
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74:04B-019
THE CONTROL OF NITRATE ACCUMULATION IN SOILS BY INDUCED DENITRIFICATION,
Avinimelech, Y. and Raveh, A.
Institute of Technology, Haifa, Israel.
The Journal of the International Association on Water Pollution Research,
Vol. 8, No. 8, p. 553-556, August, 1974. 2 fig, 1 tab, 8 ref.
Descriptors: *Nitrates, *Denitrification, Soil chemistry, Irrigation, Sprinkler
irrigation, Irrigation effects, Soil profile.
Large amounts of nitrates are accumulating in the Hula Valley soils and then
subsequently being leached to the Sea of Galilee. The nitrate concentration in
the soil has been significantly reduced by induced denitrification. Reducing
conditions have been achieved by controlled sprinkling of previously dried soil.
74:048-020
MINIMIZING THE SALT BURDENS OF IRRIGATION DRAINAGE WATERS,
Rhoades, J.D., Oster, J.D., Ingvalson, R.D., Tucker, J.M., and Clark, M.
United States Department of Agriculture, Riverside, California, Agricultural
Research Service, U.S. Salinity Laboratory, Western Region.
Journal of Environmental Quality, Vol. 3, No. 4, p 311-316, October-December,
1974. 7 tab, 7 ref.
Descriptors: *Salinity, *Saline water, *Drainage, *Drainage water, Lysimeter,
Return flow, Water quality, Water pollution, Alfalfa, Saline soil, Irrigation,
Irrigation practices.
The salt burdens of percolated drainage waters resulting from the use of waters,
synthesized to represent eight important river waters of the western USA, for
irrigation of alfalfa in a controlled lysimeter experiment, are presented.
These data show that minimizing the quantity of drainage water resulted in the
smallest possible return of applied salts in the return flow because: i) it
maximizes the precipitation of carbonate minerals and gypsum in the soil, ii)
it minimizes soil mineral weathering and the dissolution of salts previously
deposited in the soil, and iii) it maximizes the amount of soluble salt
diverted in the water that is retained in storage in the soil profile and not
returned in the drainage water.
74:048-021
GROUND WATER QUALITY RELATED TO IRRIGATION WITH IMPORTED SURFACE OR LOCAL
GROUND WATER,
Nightingale, H.I. and Bianchi, W.C.
United States Department of Agriculture, Fresno, California, Agricultural
Research Service, Water Management Research
journal of Environmental Quality, Vol. 3, !\o. 4, p 356-361, October-December,
1974. 7 fig, 2 tab, 13 ref.
Descriptors: *Groundwater, *Water quality, Salinity, Saline water, Water
pollution, Irrigation practices, Irrigation.
Ground-water quality in an arid irrigated area that imports high quality sur-
face water was compared with an adjacent up-gradient area that uses local
pumped ground water. A large irrigation canal separates the two areas which
are up-gradient from the pumping depression of the Fresno-Clovis, California
metropolitan area, which is dependent on ground water. Intensive sampling
(154 wells) was done in the fall of 1972 after it was shown by previous sampling
that the ground-water electrical conductivity (EC), N0(3), and Cl(-) content
had not significantly changed since 1967. Diagrammatic distribution maps
for ground water quality showed great variability. Areas of higher ground
Water NO(3) and Cl(-) were generally related to soil drainage-recharge and
agricultural use. The use of local ground water without supplemental surface
supplies above the canal has led to ground water EC, NO(3), and Cl(-) concen-
trations to be 9.5, 18.6, and 91.8% higher, respectively, than below the canal
which uses mostly high quality surface water.
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Section XV
WATER QUANTITY MANAGEMENT AND CONTROL
WATERSHED PROTECTION (Group 04D)
74:040-001
FIELD AND COMPUTER PROCEDURES FOR GULLY CONTROL BY CHECK DAMS,
Heede, B.H. and Mufich, J.G.
Forest Service (United States Department of Agriculture), Tempe, Arizona.
Forest Hydrology Laboratory.
Journal of Environmental Management, Vol. 2, p 1-49, 1974. 3 ref.
Descriptors: *Gully erosion, *Erosion control, *Check structures, *Sediment
control, *Computer programs, *Construction costs, *Unit costs, *Benefits,
Engineers estimates, Cost analysis, Surveys, Colorado, Rocky Mountain region,
Arizona, New Mexico.
Computerized design of gully control by check dams eases field survey and
design procedures. Only a minimum of data is required to generate the design
of gully treatments and to yield essential information on costs and materials.
Flexibility within the program is given by providing several design choices.
Graphical computer output shows the relationships between the choices by ef-
fective dam height, total cost of treatment, and benefits from expected sedi-
ment deposits. Since key equations and their derivations are presented, the
program can be adapted to dam types that differ from those used. The simpli-
fication of survey and design procedures makes feasible the inventorying of
gully control needs for larger tracts of lands. The program is operational.
74:040-002
DRIP IRRIGATION IN LANDSCAPING AND SOIL EROSION CONTROL,
Farrell, M.D.
Kuluwai Irrigation Corporation, Haleiwa, Hawaii.
Proceedings of the Second International Drip Irrigation Congress, pp. 44-45,
July 1974.
(See 74:03F-024)
74:040-003
NO-TILLAGE SYSTEM REDUCES EROSION FROM CONTINUOUS CORN WATERSHEDS,
Harrold, L.L. and Edwards, W.M.
United States Department of Agriculture, Agricultural Research Service,
Coshocton, Ohio.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 3,
Descriptors: *Soil erosion, *Corn, Crop response, Crop production, Farm
management. Climatic data, Rainfall-runoff relationships, Agriculture, Erosion,
Erosion control, Erosion rates.
Soil erosion from seven large events on the two watersheds in the same
conventional rotation corn in the 1941-1969 period were sufficiently comparable
to form a base on which to judge the effectiveness of the no-tillage system
in the 1970-1973 period. Data for the period of identical treatment show little
or no effect of land slope differences - 12.7% and 5.8%. In the period of
continuous corn, 1970-1973, erosion from the conventional tillage corn water-
shed remained high, while that from the no-tillage corn system decreased
sharply. In 1973, differences in soil erosion were striking. Photographs
taken after the July 10, 1973 event show signs of large amounts of sediment
movement from the conventional tillage corn watershed. There was no evidence of
sediment movement from the continuous corn watershed in the'no-tillage system.
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74:04D-004
WATERSHED MANAGEMENT WITHOUT SURFACE RUNOFF,
Manbeck, D.C.
Nebraska University, Lincoln, Department of Agricultural Engineering.
Water Resources Bulletin, Vol. 10, No. 3, p 586-591, June, 1974. 2 fig.
Descriptors: *Watershed management, *Surface runoff, Alternative planning,
Constraints, Design, Retention.
Legal, economic, and social constraints prevented the development of a surface
outlet from an 878 acre watershed in the eastern Great Plains. However, fre-
quent flooding of potentially excellent cropland within the watershed had to be
controlled. The process of considering various alternatives within given
constraints and utilizing natural features of the watershed to attain a water
management system without surface runoff is presented. The coordinated system
includes surface drainage, waterholding structures, and pumping plants. The
excellent water control provided permits effective utilization of more than 115
acres of land which was previously of very low productivity.
74:04D-005
EVALUATION OF PHOSPHORUS DYNAMICS IN A WATERSHED,
Cahill, T.H., Imperato, P. and Verhoff, F.H.
Tri-County Conservancy of the Brandywine, Chaddas Ford, Pennsylvania.
Journal of the Environmental Engineering Division, Vol. 100, No. EE2, p 439-458,
April, 1974. 7 fig, 6 tab, 29 ref, 2 append.
Descriptors: *Phosphorus, Watershed management, Dynamics, River flow, Rivers,
pollutants, Scour, Runoff
Investigations into the phosphate dynamics of the Brandywine River during the
summer of 1972 indicates that phosphate transport occurs by two different mech-
nisms depending upon the type flow found in the river. If the flow is steady,
the Brandywine phosphate concentrations as a function of flow exhibit what has
been termed the dilution effect. This effect is definitely shown to result from
the dilution of point source orthophosphate by the lower orthophosphate concen-
tration water coming from nonpoint sources. During unsteady stage flow, the
phosphate concentrations tends to increase with increasing water flow rate.
Two possible explanations appear plausible: the phosphate concentration is
increased by the scouring of the sediments which are high in adsorbed phosphate,
or the phosphate concentration is increased from the runoff from limited areas
near the waterway. In contrast to the steady state phosphate concentration data,
the unsteady stage data shows no significant effect of point sources of phos-
phates.
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Section XVI
WATER QUALITY MANAGEMENT AND PROTECTION
IDENTIFICATION OF POLLUTANTS (Group 05A)
74:05A-001
QUANTITATIVE METHODS FOR PRELIMINARY DESIGN OF WATER QUALITY SURVEILLANCE
SYTEMS,
Chamberlain, S.G., Beckers, C.V. Grimsrud, G.P. and Shull, R.D.
Raytheon Company, Portsmouth, Rhode Island, Oceanographic and Environmental
Services.
Water Resources Bulletin, Vol. 10, No. 2, p 199-219, April 1974. 8 fig, 2 tab,
17 ref.
Descriptors: *Monitoring, *Water quality, *Water pollution control, Network
design, Sampling, Cost-benefit analysis, Mathematical models, Data processing,
*Indiana, *Illinois.
A preliminary phase of the design of water quality surveillance systems is the
specification of sampling frequencies and station locations throughout the
basin; that is, the development of an adequate space/time sampling plan.
Quantitative methods were developed to identify candidate sets of sampling
frequencies and station locations, and to establish priorities for implementing
the different frequencies and locations. These methods are useful in cost/
effectiveness analyses, and are based on the objective of pollution abatement.
A spatial priority measure is dependent both on the water quality profile in
the stream and on the information obtained from monitoring stations in other
streams. A temporal sampling priority rating is a measure of the effective-
ness of the surveillance system with respect to its ability to detect the
violations in the standards. To illustrate the quantitative methods, the pro-
cedures were applied to the Wabash River Basin.
74:05A-002
DETERMINATION OF TRACE METALS IN SODIUM DITHIONITE-CITRATE EXTRACTS OF SOILS
AND SEDIMENTS BY ATOMIC ABSORPTION,
Jenne, E.A., Ball, J.W. and Simpson, C.
Geological Survey, Menlo Park, California, Water Resources Division.
Journal of Environmental Quality, Vol. 3, No. 3, p 281-287, July-September
1974. 2 fig, 4 tab, 32 ref.
Descriptors: *Trace elements, *Soils, *Sediments, *Chemical analysis, *Flame
photometry, Solvent extractions, Analytical techniques, Cobalt, Copper, Nickel,
Molybdenum, Zinc, Iron, Trace elements, *Pollutant identification.
A general method was developed for the analysis of Co, Cu, Ni, Mo, and Zn in
dithionite-citrate extracts of soils and sediments. Because of the high Zn
content of dithionite, it is necessary to preclean the dithionite-citrate
solution before it is used to extract soils or sediments. This precleaning
lowers the detection level significantly for other trace elements as well.
Since Fe causes flame interferences in atomic absorption, the size of the
individual sample aliquot taken to chelation-solvent concentration is varied
to provide a constant quantity of Fe (5ng). The standards and blanks are ad-
justed to the same Fe content. This approach is necessitated by the wide dif-
ferences in the Fe concentrations of the dithionite-citrate extracts. Follow-
ing pH adjustments and addition of ammonium-1-pyrrolidine dithiocarbamate,
the trace metals (and Fe) are concentrated via two successive 10ml methyl
isobutyl ketone extractions. Quantities of Fe much greater than 5ng interfere
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in the solvent concentration step. Natural organics released by the dissolu-
tion of free-Fe and -Mn oxides, to the extent that they are represented by
fulvic acids, do not cause any significant interference.
74:05A-003
THE UNRELIABILITY OF TILE EFFLUENT FOR MONITORING SUBSURFACE NITRATE-NITROGEN
LOSSES FROM SOILS,
Thomas, G.W. and Barfield, B.J.
journal of Environmental Quality, Vol. 3, No. 2, p 183-185, April-June, 1974.
1 fig, 2 tab, 5 ref.
Descriptors: *Nitrate, *Nitrogen, *Denitrification, Drainage, Tile drainage,
Soil water movement, Soil investigations, Seepage
Investigation of a completely tiled field showed that only a small proportion
of the total flow reaching the drainage ditch came from tile effluent. In
two measurements, 63 and 89% of the flow to the drainage ditch came from
seepage other than through tiles. The nitrate-nitrogen concentrations in the
tile effluent were far higher than those calculated in the non tile flow by
mass balance. We conclude that nitrate-nitrogen concentrations in tile efflu-
ents may not be reliable indicators of nitrate-nitrogen losses from agricultural
land, when the tiles do not intercept all subsurface flow.
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Section XVII
WATER QUALITY MANAGEMENT AND PROTECTION
SOURCES OF POLLUTION (Group 05B)
74:05B-001
NONLINEAR PROGRAMMING IN RIVER BASIN MODELING,
Bayer, M.B.
Calgary University, Alberta, Faculty of Business.
Water Resources Bulletin, Vol. 10, No. 2, p 311-317, April 1974. 3 tab, 31
ref.
Descriptors: *Water quality control, *Model studies, *River basins, Linear
programming, *Dynamic programming, Costs, Optimization, Treatment facilities,
Biochemical oxygen demand, Dissolved oxygen, Standards, Streams, Systems
analysis, *Oregon.
Since the real world is seldom linear, nonlinear programming is theoretically
the ideal method for obtaining solutions for complex water quality problems.
The use of nonlinear programming in river basin water quality modeling is
explored. Applications recently reported in the literature, along with the
author's experience with nonlinear programming, are reviewed. Several diffi-
culties which still exist in applying the method are discussed. Computational
results obtained using linear, dynamic, and nonlinear programming to solve
a river basin water quality optimization problem are compared. Data are from
Liebman's simplified version of the Willamette River system in Oregon. The
water quality models have objective functions with continuous first partial
derivatives, and several inequality and variable bound constraints. Results
obtained are the efficiencies of treatment plants and the total cost of build-
ing or expanding the treatment plants to accommodate specified BOD loads and
stream DO standards. Compared are a linear and nonlinear program of Bayer,
a dynamic program of Liebman, and a linear program of ReVelle.
74:058-002
ADSORPTION OF PHOSPHATE BY RIVER PARTICULATE MATTER,
Wang, W-c.
Illinois State Water Survey, Peoria. Water Quality Section.
Water Resources Bulletin, American Water Resources Association, Vol. 10, No.
4, p 662-671, August 1974. 6 fig, 1 tab, 13 ref.
Descriptors: *Adsorption, *Sediments, *Phosphates, Water pollution sources,
Isotherms, Montmorillonite, Bentonite, Laboratory tests. Suspended solids,
Illinois.
Adsorption of orthophosphate on samples of particulate matter taken from the
Illinois and Spoon Rivers was investigated under laboratory conditions. Ad-
sorption equilibria were reached in four to six days. Average adsorption
rates between 0.0239 and 0.0366 were found during equilibration periods.
Adsorption isotherms were computed, both for constant and for varying amounts
of particulate matter in the two rivers. During investigation of the effects
of pH on phosphate adsorption, the highest adsorptive capacities were found at
natural pH values of 8.3-8.4. Reductions in pH dr-opped this capacity to a
minimum at pH6. Some slight recovery of capacity was observed at pH5 and 4.
Rates of adsorption were influenced by the equilibrium concentration of phos-
phate-P and were essentially the same for the Illinois and Spoon Rivers. How-
ever, based upon the quantity of phosphate-P adsorbed per unit weight of par-
ticulate matter present, the capacity of the Illinois was seven times that of
the Spoon River. Adsorption isotherms for both streams were essentially linear,
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suggesting a functional relation between unit adsorption and particulate matter
content. A concurrent study of samples collected daily from the Illinois River
failed to show a similar correlation of particulate matter and phosphate adsorp-
tion.
74:05B-003
NUMERICAL AND ANALYTICAL SOLUTIONS OP DISPERSION IN A FINITE, ADSORBING POROUS
MEDIUM,
Marino, M.A.
California University, Davis, Department of Water Science and Engineering.
Water Resources Bulletin, Vol. 10, No. 1, p 81-90, February 1974. 1 fig, 6
ref.
Descriptors: *Dispersion, *Path of pollutants, *Porous media, *Numerical
analysis, Mathematical models, Groundwater movement, Adsorption.
Numerical and analytical solutions are developed for the distribution of a
contaminant within an adsorbing porous medium in a unidirectional flow field
subject to a step function for input concentration. The medium is considered
to be homogeneous, isotropic, and areally finite. As a byproduct, solutions
are also obtained for the case of a nonabsorbing porous medium. An example
that demonstrates the applicability of the solutions is presented.
74:05B-004
EFFECT OF TWO IMPOUNDMENTS ON THE SALINITY AND QUANTITY OF STORED WATERS,
pionke, H.B. and Workman, O.D.
Agricultural Research Service, chickasha, Oklahoma, Southern Great Plains
Watershed Research Center.
Water Resources Bulletin, Vol. 10, No. 1, p 66-80, February 1974. 6 fig, 2
tab, 7 ref.
Descriptors: *Salinity, *Evaporation, *Reservoirs, *Oklahoma, Water quality,
Water pollution sources, Seepage, saline water, Flood control, Water chemistry,
Impoundments.
The effect of hydrologic and chemical processes on salinization of stored
waters was determined for two small floodwater-retarding structures located in
western Oklahoma. One structure, designed to accommodate a large influx of
sediment, was overdesigned (operated at reduced capacity) by upstream diversion
of approximately one-half the inflow. Over a 2-year period, the total salinity
of stored waters increased approximately 22 times, and the stored water volume
decreased to 1/33 its initial volume in the overdesigned (underused) structure,
while both volume and salinity of stored waters remained comparatively stable
in the other structure. The lack of sufficient dilution by better quality
surface runoff and the increased residence time of water in the impoundment
apparently caused most of the salinity increase. The bulk of the salt load
entering the overdesigned structure, to be concentrated later by evaporation,
was associated with base rather than storm inflow. After base inflow ceased,
substantial losses of salt load and stored water occurred concurrently. The
loss was not adequately explained by chemical precipitation in association
with evaporation. Seepage and evaporation appeared to account for much of
the hydrologically unexplained loss of stored waters.
74:05B-005
WATER QUALITY SIMULATION AND APPLICATION,
Lombardo, P.S. and Ott, R.F.
Environmental Research and Technology, Incorporated, Lexington, Massachusetts.
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Water Resources Bulletin, Vol. 10, No. 1, p 1-9, February 1974. 5 fig, 10
ref.
Descriptors: Water resources development, *Management, *Long-range planning,
*Water quality, *Simulation analysis, *Optimum development plans, River basins,
Water utilization, *Washington, Biochemical oxygen demand, Dissolved solids,
Climatic data, Hydrologic data, Mathematical models, Systems analysis, Evalua-
tion, Equations.
An understanding of the causes of aquatic system behavior leading to proper
system management is enhanced by knowledge obtained through water quality
modeling. For accurate assessment of the quality of a water body, the dynamic
and synergistic character of the aquatic environment necessitates knowing the
temporal and spatial varying behavior of various water quality indices. Through
mathematical formulations of the physical, biological and chemical processes
occurring in the aquatic ecosystem, water quality models attempt to simulate
the spatial and temporal variations in water quality indices. Described in
detail is the Hydrocomp Water Quality Simulation Model and its application
to the Seattle metropolitan area. Model input includes rate of coliform die-
away and BOD decay and climatological and hydrologic data; determination of
total dissolved solids is done predominantly by a mass balance equation. The
Seattle study searches for a plan to ensure the best utilization of the total
water resources available to the Cedar and Green River basins, and includes
evaluation of interbasin transfer. The Model provides a means for evaluating
management policies in terms of the water quality indices. Through information
generated on the probable resulting effects of policies, optimization of the
various alternatives could be achieved.
74:053-006
PREDICTING PESTICIDE RUNOFF FROM AGRICULTURAL LAND: A CONCEPTUAL MODEL,
Bailey, G.W., Swank, R.R., Jr., and Nicholson, H.P.
Environmental Protection Agency, Athens, Georgia, Agro-Environmental Systems
Branch.
Journal of Environmental Quality, Vol. 3, No. 2t p 95-102, April-June 1974.
4 fig, 47 ref.
Descriptors: *Path of pollutants, *Pesticides, *Runoff, *Mathematical models,
Model studies, Rainfall-runoff relationships, Translocation, Erosion, Pesticide
kinetics.
A mathematical model of the dynamic, single-rainfall-event type describes
pesticide runoff as a function of pesticide and soil properties, agricultural
practices, watershed characteristics, and climatic factors. The conceptual
structure of the model includes source term effects, loss of pesticide from
the soil surface during runoff producing rainfall events because of mass trans-
fer from soil surface into the moving runoff film and pickup of sediment con-
taining pesticide particulates.
74:05B-007
RELATIVE MOVEMENT OF BROMIDE AND NITRATE THROUGH SOILS,
Smith, S.J. and Davis, R.J.
Agricultural Research Service, Durant, Oklahoma, Water Quality Management
Laboratory.
Journal of Environmental Quality/ Vol. 3, No. 2, p 152-155, April-June 1974.
3 fig, 4 tab, 14 ref.
Descriptors: *Leaching, *Path of pollutants, *Nitrates, *Bromides, Biodegrada-
tion. Nutrients, Anion exchange, Soils.
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Miscible displacement experiments were conducted with eight different surface
soils (0-15 cm depth) and their associated subsoils (61-76 cm depth). Results
indicate that the movement of bromide relative to that of nitrate is identical
in subsoils but variable in surface soils. Differences in relative movement
of the two anions may be attributed to microbial activity involving nitrate.
With the exception of 5% anion sorption in a Greenville subsoil, anion ex-
clusion values ranged from 5% to 39%, indicating the anions were moving 1.05
to 1.64 times as fast as they would if they had been uniformly associated with
all the soil water. The results support the view that bromide has utility for
following the potential path of nitrate movement through soils.
74:058-008
BROSIONAL LOSSES OP S-TRIAZINE HERBICIDES,
Hall, J.K.
Pennsylvania state University, University Park, Department of Soil Chemistry.
journal of Environmental Quality, Vol. 3, No. 2, p 174-180, April-June 1974.
4 fig, 2 tab, 15 ref.
Descriptors: *Soil erosion, *Runoff, *Herbicides, *Path of pollutants, *Pesti-
cide residues, Pesticides, Alfalfa, Corn(Field).
Erosional losses of two chloro-s-triazines, atrazine and GS13529, were evalu-
ated in 1970 and 1971 from field runoff plots planted to corn and situated
on Hagerstown silty clay loam of 14% slope. Losses of a methoxy-s-triazine,
GS14254, were assayed in 1971 and 1972 from an alfalfa stand. Herbicides
were applied premergent to corn and to dormant alfalfa only once during the
initial growing season or initial season of evaluation of two rates, 2.2 and
4.5 kg/ha» Total losses of atrazine during the first and most critical season
at the respective rates were 5.0% and 4.8% of that applied; 87% to 93% of this
loss resulted within the first month following application. One month after
application an average of 35.3% of the applied atrazine remained; five months
later an average level of 11.8% was residual. Recovery of GS13529 ranged
from 65.5% to 9.8% for the same time period. Runoff losses of GS14254 from
alfalfa were inconsequential. Little runoff was obtained from this cropping
system, no sediment was ever collected and runoff concentrations of the herbi-
cide were extremely small. Total losses of this herbicide for the year were
0.02 and 0.03% for the respective application rates.
74:05B-009
NITRATE-NITROGEN AND PHOSPHORUS CONTENTS OF STREAMS DRAINING SMALL AGRICULTURAL
WATERSHEDS IN KENTUCKY,
Thomas, G.W. and Crutchfield, J.D.
Kentucky University, Lexington, Department of Agronomy.
journal of Environmental Quality, Vol. 3, No. 1, p 46-49, January-March 1974.
5 fig, 2 tab, 3 ref.
Descriptors: *Nitrates, *Phosphorus, *Small watersheds, *Kentucky, *Land use.
Fertilizers, Hydrogeology, Water pollution sources.
Eight streams draining agricultural watersheds representative of the important
physiographic regions of Kentucky were sampled monthly from January through
May in both 1971 and 1972. The objective was to determine the effects of land
use and geology on the concentrations of nitrate-N and P in the stream water.
land use ranged from almost completely forested to mostly cultivated.
was no good relationship between nitrate-N and land use. Nitrate-N
varied from 6 ppm to zero, with the highest value found in a stream draining
a watershed which was 98% in bluegrass pasture. The P concentrations in the
gtream water were closely related to local geology and not to land use. A
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comparison between the 1921 data and 1971-72 data from the same geological
areas showed very little change in mean nitrate-N or P concentrations.
74:05B-010
SURFACE RUNOFF LOSSES OF SOLUBLE NITROGEN AND PHOSPHORUS UNDER TWO SYSTEMS
OF SOIL MANAGEMENT,
Klausner, S.D., Zwerman, P.J. and Ellis, D.F.
Cornell University, Ithaca, New York, Department of Agronomy.
Journal of Environmental Quality, Vol. 3, No. 1, p 42-46, January-March 1974.
4 fig, 4 tab, 15 ref.
Descriptors: *Agricultural runoff, *Nitrogen, *Phosphorus, *Soil management,
Nutrients, Agriculture, Rainfall-runoff relationships. Crops, Fertilization,
Eutrophication, Rotation, *New York.
Annual loss of soluble nitrogen and inorganic phosphorus from field plots,
due to rainfall, was determined. Influence of a crop rotation, soil manage-
ment practices and fertilizer rates was evaluated. The experimental area is
composed of approximately 12 ha of a Lima-Kendaia soil association. The soil
texture is silt loam and is moderately to somewhat poorly drained. A three-
year crop rotation of corn, beans, and wheat were combined factorially with two
levels of fertility and two soil management schemes and replicated twice. The
crop rotation has persisted for 15 years and has gone through five cycles.
The soil management variable had remained the same for each plot during this
period. The data present the annual losses of soluble N and P in the liquid
fraction of surface runoff, as a function of past soil management practices
and present fertility levels. Mean annual surface runoff volumes were approxi-
mately twice as high from poorly managed soils than from well-managed soils.
Except for heavy fall fertilization of N on poorly managed soils, total
yearly accumulative N discharge in surface runoff did not exceed amount deliv-
ered in rainfall as measured over 10 months. Phosphorus losses exceeded the
amount contained in rainfall.
74i05B-011
PHOSPHORUS RELATIONSHIPS IN RUNOFF FROM FERTILIZED SOILS,
Romkens, M.J.M. and Nelson, D.W.
Agricultural Research Service, Lafayette, Indiana.
Journal of Environmental Quality, Vol. 3, No. 1, p 10-13, January-March 1974.
4 fig, 2 tab, 14 ref.
Descriptors: "Water pollution sources, *Phosphorus, "-Fertilizers, *Phosphates,
*Soil water movement, Erosion, Sediments, Path of pollutants.
The effect of fertilizer mixed into soil on the amount of phosphorus in run-
off was studied. Runoff samples from artificial rainstorms on fallow plots
of Russell sil soil, and P enriched soil-water mixtures (1:50) of Russell sil
and other soils were analyzed for water soluble orthosphosphate and extractable,
total, and organic P in sediment. The relation of P addition rate to the
soluble orthosphosphate or sediment extractable phosphorus level in runoff was
approximately linear. The relation of soluble orthophosphate to extractable
P in soil-water systems was linear for most soils studied. Soluble orthosphos-
phate and extractable P in sediment were not related to total P or to organic
P in sediment. A procedure is suggested for estimating the soluble ortho-
phosphate concentration in runoff from fertilized wet soil using laboratory
analyses.
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74»05B-012
NUTRIENTS IN SUBSURFACE AND RUNOFF WATERS OF THE HOLLAND MARSH, ONTARIO,
Nicholls, K.H. and MacCrimmon, H.R.
Ministry of the Environment, Rexdale, Ontario, Water Quality Branch.
Journal of Environmental Quality, Vol. 3, No. 1, p 31-35, January-March 1974.
3 fig, 2 tab, 18 ref.
Descriptors: *Nutrients, *Path of pollutants, Water pollution sources,
*Marshes, Soils, *Canada, *Fertilizers, *Nitrogen, *Phosphorus, Nitrates,
Nitrites, Runoff.
Relative contributions to the river of nutrients (NO3, NO2, and total and
soluble reactive phosphorus) and total electrolyte (specific conductance)
were determined in surface runoff water pumped from both cultivated and un-
cultivated plots of much soil within the Holland Marsh, Ontario. In addition,
subsurface water from piezometers installed in both cultivated and uncultivated
marsh soil was analyzed throughout the growing season to determine fundamental
differences in water chemistry and the extent of leaching of N and P under both
cultivated and uncultivated conditions. The time and amount of rainfall are
important in determining nitrate-N and to a lesser extent, soluble reactive P
concentrations in subsurface water beneath the cultivated plot but not beneath
the uncultivated plot. The mean concentration (0.75 mg/liter) of inorganic
N in subsurface water under the cultivated plot was about 10 times higher than
under uncultivated marsh during the growing season. The combined effects of
fertilization, drainage and hence oxidizing and nitrifying conditions yielded
4 to 5 times more P (1.56 kg P/ha) and 40 to 50 times more nitrate-N (4.1 kg
N/ha) in runoff water from the cultivated than from the uncultivated plot.
From the cultivated plot the nutrients are lost to the river during a 5 to
6 week pumping period during the spring and more than 90% of the total P in
runoff is in the soluble reactive form (as opposed to only 45% from the un-
cultivated marsh) and is, therefore, readily available for algae and aquatic
plant growth in the lower Holland River and Cook Bay of Lake Simcoe.
74:05B-013
MODELING FLOW AND CHEMICAL QUALITY CHANGES IN AN IRRIGATED STREAM-AQUIFER
SYSTEM,
Konikow, L.F. and Bredehoeft, J.D.
Geological Survey, Lakewood, Colorado.
Water Resources Research, Vol. 10, No. 3, p 546-562, June 1974. 25 fig, 3
tab, 30 ref.
Descriptors: *Water quality, *Groundwater movement, *Path of pollutants,
*Return flow, *Numerical analysis, Surface-groundwater relationships. Un-
steady flow, Mathematical models, Alluvial channels, Dissolved solids, Con-
junctive use, *Colorado.
Salinity increases in groundwater and surface water in the Arkansas River
valley of southeastern Colorado are primarily related to irrigation practices.
A digital computer model was developed to predict changes in dissolved solid
concentration in response to spatially and temporally varying hydrologic
stresses. The equations that describe the transient flow of groundwater and
the transport and dispersion of dissolved chemical constituents were solved
numerically. The model simulated flow as well as changes in water quality
for both the stream and the aquifer. Detailed field measurements made for
a l-Yr period in an 11-mi reach of the valley between LaJunta and the
Bent-Otero country line were used to verify and calibrate the model. Measured
water levels varied by an average of about 3 ft during the study period, and
calculated water table elevations in the aquifer were within 1 ft of the ob-
served values approximately 90% of the time. The specific conductances of
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water samples from five wells in one well field had a standard deviation of
about 10% of the mean. Dissolved solid concentrations calculated by the model
were within 10% of the observed values for both the aquifer and the stream
approximately 80% of the time.
74:05B-014
QUALITY OF WATER DISCHARGED FROM TWO AGRICULTURAL WATERSHEDS IN SOUTHWESTERN
IOWA,
Burwell, R.E., Schuman, G.E., Piest, R.F., Spomer, R.G. and McCalla, T.M.
Agricultural Research Service, Council Bluffs, Iowa, North Central Watershed
Research Center.
Water Resources Research, Vol. 10, No. 2, p 359-365, April 1974. 5 tab, 15
ref.
Descriptors: *Water quality, *Sediment yield, *Soil conservation. Land manage-
ment, *Iowa, Pesticides, Contour farming, Terracing, Farm management.
To evaluate the influence of the level-terrace conservation practice on water,
sediment, and plant nutrients discharged in surface runoff and base flow, data
obtained from this watershed were compared with data obtained from a 33.6-ha
contour-planted corn-cropped watershed near Treynor, Iowa. The quality of
water discharged from the 157.5-ha diversified conservation-farmed watershed
in southwestern Iowa was within acceptable limits for potable water except
for the levels of ammonia, inorganic phosphorus, and coliform. Total coli-
form levels exceeded the established criteria on two occasions, and fecal
coliform once during the 2-year study. Nutrient concentration was high oc-
casionally, but the nutrient quantities discharged from the watershed were
low, showing the effectiveness of the level-terrace system in controlling sur-
face runoff and erosion. Atrazine residue in the runoff and sediment was
detected in only one sample. Even though several chlorinated hydrocarbon and
organophosphate compounds had been applied to the watershed, none was detected
in runoff or sediment. A comparison of the data from the 33.6-ha contour-
farmed watershed with the data from the 157.5-ha well-planned conservation
watershed showed the benefits and necessity of controlling runoff and erosion
to prevent loss of agricultural chemicals.
74:05B-015
SOLUBLE PHOSPHATE OUTPUT OF AN AGRICULTURAL WATERSHED IN PENNSYLVANIA,
Gburek, W.J. and Heald, W.R.
Agricultural Research Service, University Park, Pennsylvania, Northeast Water-
shed Research Center.
Water Resources Research, Vol. 10, No. 1, p 113-118, February 1974. 1 fig,
1 tab, 10 ref.
Descriptors: *Phosphates, *Water pollution sources, *Fertilizers, Leaching,
Land use, *Pennsylvania, Path of pollutants, *Agricultural watersheds.
Soluble phosphate data were collected from the stream draining a 7.7 sq km
Pennsylvania agricultural watershed. The stream approaches constant and low
phosphate concentrations of 10 ppb or less P04-P during continuing base flow
recession. Concentrations vary seasonally, 10 to 15 ppb P04-P commonly oc-
curring in the summer. Less than 2% of the P appLied to the watershed as
fertilizer is carried out of the watershed by the -stream in the soluble form.
Most of this output is associated with the high flows and low concentrations
found in the early spring. The land adjacent to the stream channel and its
indigenous vegetation can be a direct source of soluble phosphate to the
stream during periods of precipitation. This makes the PO4-P levels observed •
at the watershed outlet the result of near- and in-stream processes and reduces
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the importance of general land use of a watershed as a determining factor in
the soluble phosphate concentrations in the stream.
74:053-016
WATER QUALITY MODELS USING THE BOX-JENKINS METHOD,
Huck, P.M. and Garquhar, G.J.
Environmental Protection Service, Burlington, Ontario, Waste Water Technology
Centre.
journal of the Environmental Engineering Division, American Society of Civil
Engineers, Vol. 100, Ho. EE3, Paper 10629, p 733-752, June 1974. 9 fig, 7
tab, 13 ref, append.
Descriptors: *Time series analysis, *Path of pollutants, Water quality,
*Statistical models, Water pollution^ Chlorides, Dissolved oxygen. Model
studies, Time series analysis.
The Box-Jenkins method, a time-based technique for time series analysis, is
successful in modeling chloride and dissolved oxygen data for the St. Glair
River near Corunna, Ontario. The technique is superior in the situation to
either a frequency-based approach or a deterministic causative model. The
model building process includes identification, estimation, and diagnostic
checking stage. Forecasting and interpretation follow the derivation of
successful models. An autoregressive type of model best represents the chlo-
ride data, and a moving average process represents the dissolved oxygen.
Similar causative mechanisms appear to influence June and December chloride
and June dissolved oxygen.
74:05B-017
A KINETIC STUDY OP AMMONIUM AND NITRITE OXIDATION IN A SOIL FIELD PLOT,
Ardakani, M.S., Schulz, R.K. and McLaren, A.D.
California University, Berkeley, Department of Soils and Plant Nutrition.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 273-277, March-
April 1974. 6 fig, 1 tab, 13 ref.
Descriptors: *Oxidation, *Ammonia, *Nitrates, Soils, Nitrification, Denitri-
fication. Soil microorganisms. Adsorption, Biodegradation.
Disappearnace of NH4 from percolating solution in a field test was attributed
to both oxidation and to adsorption by the soil. Once a steady state was
established and exchangeable NH4 was equilibrated with NH4 in soil solution,
oxidation alone accounted for disappearance of NH4 in the top 2.5 cm of the,
soil. Concentration profiles of NO2 and NO3 may be described by a modified
Michaelis-Menten equation. Rate constants for oxidation of N02 and NH4 are
0.0006 and 0.0025, respectively. These rates are in good agreement with the
values found under controlled laboratory conditions. Growth and distribution
in soil of Nitrobacter and Nitrosomonas were followed by weekly estimates of
their numbers at different depths. Nitrobacter reached a maximum population
of about 1 million per cc of soil but declined to a stable density of about
100,000 organisms per cc. Nitrobacter approached a steady level of about
10,000 organisms per cc. Both organisms showed higher densities near the soil
surface where the concentrations of substrates were always highest.
74:053-018
NITROGEN TRANSFORMATIONS DURING CONTINUOUS LEACHING,
Starr, J.L., Broadbent, F.E. and Nielsen, D.R.
California University, Davis, Department of Soils and Plant Nutrition.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 283-289, March-
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April 1974. 9 fig, 17 ref.
Descriptors: *Nitrification, *Denitrification, *Leaching, *Unsaturated flow,
Ammonia, Oxidation, Soil water movement, Diffusion, Path of pollutants,
Equations, Reduction(Chemical).
Simultaneous nitrification, denitrification, and N movement were investigated
in a soil column during continuous unsaturated leaching. During a continuous
application of NH4C1 solution, analyses were made of the soil solution with
soil depth and time for N as NH4, N02 and NO3; and of the soil atmosphere
for 02, CO2, N2O, and N2. The use of N-15 permitted direct measurement and
quantification of nitrification and denitrification, as well as the transport
of N in the liquid and gaseous phases. Solutions to the appropriate equations
using measured reaction rate coefficients, pore-water velocities, and diffusion
coefficients adequately described the steady state NH4 and NO3 concentration
distribution in the soil profile. Equations were also used to stoichiometri-
cally account for the various interacting species in the N transformations.
74:058-019
NITROGEN TRANSFORMATIONS IN SOIL DURING LEACHING: I. THEORETICAL CONSIDERA-
TIONS ,
Misra, C., Nielsen, D.R. and Biggar, J.W.
California University, Davis, Department of Water Science and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 289-293, March-
April 1974. 12 ref.
Descriptors: *Nitrification, *Denitrification, *Leaching, *Unsaturated flow,
Ammonia, Oxidation, Soil water movement, Diffusion, Path of pollutants,
Equations, Reduction(Chemical).
Transport equations describing the movement and simultaneous oxidation of NH4
to NO3 and reduction of NO3 and N2 by microbial and chemical means were set
up and solved both for leaching of a pulse and for a continuous application
at the soil surface. Both ionic adsorption owing to cation exchange and
microbiological transormations were considered and distinguished as reversible
and irreversible processes, respectively. The possibilities of the model ex-
tended to a sequential transformation during transport of more than two ni-
trogen species have been examined.
74:058-020
NITROGEN TRANSORMATION IN SOIL DURING LEACHING: II. STEADY STATE NITRIFI-
CATION AND NITRATE REDUCTION,
Misra, C., Nielsen, D.R. and Biggar, J.W.
California University, Davis, Department of Water Science and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 294-299,
March-April 1974. 5 fig, 1 tab, 19 ref.
Descriptors: *Nitrification, *Denitrificaion, *Leaching, *Unsaturated flow,
Ammonia, Oxidation, Soil water movement, Diffusion, Path of pollutants,
Equations, Reduction(Chemical).
Nitrogen transformations were examined by means of a miscible displacement
technique that permitted passage of air with different levels of oxygen through
the soil. With the use of steady-state solutions of equations describing the
convective transport of NH4 and NO3 ions in Columbia silt loam, first-order
reaction rate constants kl and k2 were ascertained for NH4-oxidation and NO3-
reduction, respectively. Values of kl were 10-fold greater than those of k2.
At an oxygen level of 0.5% in the gaseous phase, nitrification was apparently
inhibited.
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74:05B-021
NITROGEN TRANSFORMATIONS IN SOIL DURING LEACHING: III. NITRATE REDUCTION IN
SOIL COLUMNS,
Misra, C., Nielsen, D.R. and Biggar, J.W.
California University, Davis, Department of Water Science and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 300-304,
March-April 1974. 7 fig, 1 tab, 11 ref.
Descriptors: *Nitrification, *Denitrification, *Leaching, *Unsaturated flow,
Ammonia, Oxidation, Soil water movement. Diffusion, Path of pollutants.
Equations, Reduction(Chemical).
Nitrate reduction in water-unsaturated Columbia silt loam columns was ex-
amined at 19.5C and 34.5C with three levels of oxygen (0.5%, 5%, and 20%)
in an aerating gas passing through the soil. Following a continuous appli-
cation of NH4 solution, a pulse of a NO3 solution was leached through the
columns. After the decay of the pulse, a continuous application of NO3
solution allowed mathematical analysis leading to ascertaining N03 reduction
rate coefficients. The temperature dependence of these constants as a function
of oxygen composition and the need for microbial population and activity anal-
ysis are discussed.
74:05B-022
SOLUTE MOVEMENT THROUGH DISTURBED AND UNDISTURBED SOIL CORES,
cassel, O.K., Krueger, T.H., Schroer, F.W. and Norum, E.B.
North Dakota State University, Fargo, Department of Soils.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 36-40, January-
February 1974. 9 fig, 19 ref.
Descriptors: *Solutes, *Translocation, *Soil water movement, *Unsaturated
flow, *Path of pollutants, Nitrification, Dispersion, Leaching, Chlorides,
Nitrates.
Displacement of nitrate and Cl-36 were measured in disturbed (reconstituted
horizon by horizon) and undisturbed soil profiles of Aberdeen loam and Beotia
loam representing strong and moderate soil structure, respectively. Each soil
core was 30 cm in diameter and at least 80 cm high. Mean water content of the
undisturbed soil profile was greater and mean bulk density less than the
corresponding values for the disturbed cores for each soil. For example,
disturbance increased mean water content by 0.07 for Beotia loam with a 0.01
g/cc decrease in bulk density; disturbing Aberdeen decreased bulk density from
1.47 to 1.30 g/cc but increased mean water content only 0.03. The disturbed
soils required greater throughout volume of distilled water to displace the
solutes and had smaller dispersion coefficients than the undisturbed soils.
For a given effluent sample, relative nitrate concentration was consistently
greater than relative Cl-36 concentration due to nitrification occurring
within both the disturbed and undisturbed soil profiles during the 24-week
period.
74:05B-023
NITROGEN MINERALIZATION-WATER RELATIONS IN SOILS,
Stanford, G. and Epstein, E.
Agricultural Research Service, Beltsville, Maryland, Agricultural Environ-
mental Quality Institute.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 103-106,
January-February 1974. 3 fig, 1 tab, 8 ref.
Descriptors: *Nitrogen, *Soil chemistry, *Water chemistry, *Soil moisture,
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Moisture tension. Regression analysis, Porosity, Soil texture, Nitrification,
Denitrification, Path of pollutants.
The relationships between soil N mineralization, soil water content, and
matric suction were studied in nine soils of widely differing chemical and
physical properties. Highest N mineralization rates occurred between matric
suctions of 1/3 to 0.1 bar, in which range 80% to 90% of the total pore space
was filled with water. In the range from optimum soil water content (1/3 to
0.1 bar) to 15 bars, a near-linear relation generally existed between amounts
of mineral N accumulated and soil water contents. With increasing dryness,
N mineralization continued to decline. Water levels above optimum often re-
duced mineral N accumulations, presumably because of denitrification. Upon
expressing the values for N mineralization (Y) and soil water content (X)
for each soil on a relative basis with respect to maximum N mineralized
(Y = 100), the regression of Y on X did not differ among soils. Regression
coefficients for common (based on covariance) and total regressions, respec-
tively, were 1.07 and 1.02. Corresponding Y-intercepts were -2 and -4. A
reasonable approximation of the regression is Y = X.
74:05B-024
MINERAL NITROGEN MOVEMENT INTO SUBSOILS FOLLOWING CONTINUED ANNUAL FERTILIZATION
FOR CORN,
MacGregor, J.M., Blake, G.R. and Evans, S.D.
Minnesota University, St. Paul, Department of Soil Science.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 110-113,
January-February 1974. 2 fig, 2 tab, 15 ref.
Descriptors: *Path of pollutants, *Fertilizers, *Nitrates, *Leaching, Nitri-
fication, Denitrification, Ammonia, Nitrogen, Soil water movement, Percolation,
Irrigation effects, Tile drainage.
t
Nitrogen movement was studied in two clay loam soils fertilized in planting
for corn (Zea mays L.) for 10 or 15 growing seasons at annual rates of 0,
44.8 or 268.8 kg N/ha. After 10 growing seasons, little NO3-N remained below
drainage tile depth in LeSueur clay loam. After 11 growing seasons on untiled
Forman clay loam, considerable NO3-N was found at depths to 6 or 7 meters.
After 15 years, appreciable nitrate occurred to the 10-m depth. The average
rates of movement of the NO3 front for the 10 and the 15-year periods were
1.7 and 1.9 mm/day, respectively. Concentrations of ammonium N were similar
under all fertilizer treatments. Annual N additions failed to significantly
increase corn grain yields on LeSueur clay loam but significantly increased
yields on Forman clay loam.
74:058-025
NITRIC OXIDE SORPTION BY CALCAREOUS SOILS: II. EFFECT OF MOISTURE ON CA-
PACITY, RATE, AND SORPTION PRODUCTS,
Miyamoto, S., Prather, R.J. and Bohn, H.L.
Arizona University, Tucson, Department of Soils, Water and Engineering.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 71-74, January-
February 1974. 6 fig, 3 tab, 8 ref.
Descriptors: *Sorption, *Nitrogen, *Waste disposal, Path of pollutants, Air
pollutants, Calcareous soils. Soil disposal fields.
At room temperature, the nitric oxide (NO) sorption capacity of calcareous
soils increased with the presence of moisture in an air + NO stream (1.5%
NO by volume) and in the soils. The largest increase, up to 10-fold or ap-
proximately to the acidtitratable basicity of soils, occurred when NO and
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H2O were sorbed simultaneously by initially dry soils from a moist air
(humidity >95%) + NO stream. The sorption rates were proportional to the
unused portion of the capacity with the rate constants ranging from 0.02
to 0.03 per min for NO and 0.01 to 0.015 per min for H2O under simultaneous
sorption. Initially moist soils sorbed NO from a dry air (humidity < 5%) +
NO stream until the soils dried. The rate of NO sorption slowed at initial
soil water suctions leas than approximately 1 bar. Sorbed NO was recovered
as nitrate and reacted with the basicity in moist soils. Less than 20% of
the sorbed nitrogen was lost upon heating at 105 deg C for 24 hours.
74:053-026
KINETICS OF THE PHOSPHATE INTERACTION WITH CALCITE,
Griffin, R.A. and Jurinak, J.J.
Utah State University, Logan, Department of Soil Science and Biometeorology.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 75-79, January-
February 1974. 6 fig, 1 tab, 19 ref.
Descriptors: *Phosphates, *Calcite, *Sorption, *Adsorption, Thermodynamics,
Solubility, Kinetics, Free energy, Soil chemistry, Mineralogy, Water chemistry.
Phosphate interaction with calcite did not proceed in the absence of the cal-
cite surface. The kinetics of interaction could be described by two simul-
taneous reactions. The first reaction was second-order and was ascribed to the
adsorption of phosphate on the calcite surface. The second reaction was first-
order and was associated with the surface arrangement of phosphate clusters
into calcium phosphate heteronuclei. Solubility criteria show that at low
phosphate concentrations the ultimate clacium phosphate surface mineral formed
was hydroxylapatite. Desorption kinetics were studied by using an anion ex-
change resin technique. The desorption process could be described as two
simultaneous first-order reactions. The desorption mechanism corresponds to
the dissolution of a surface nucleated calcium phosphate mineral, with the
second reaction step being the desorption of phosphate from the calcite sur-
face sites. The rate constants for adsorption and desorption were determined
at four temperatures between 0 deg C and 40 deg C and were used to compute the
activation energies of adsorption and desorption. In addition, the enthalpy
of activation, the entropy of activation, and the free energy of activation
for both the adsorption and desorption processes were computed.
74-05B-027
TRANSFORMATION OF IRON IN A WATERLOGGED SOIL AS INFLUENCED BY REDOX POTENTIAL
AND PH,
Gotoh, S. and Patrick, W.H., Jr.
Louisiana State University, Baton Rouge, Department of Agronomy.
Soil Science Society of America Proceedings, Vol. 38, No. 1, p 66-71, January-
February 1974. 5 fig, 1 tab, 32 ref.
Descriptorst *Iron, *Soil chemistry, *Water chemistry. Oxidation, Hydrogen
ion concentration, Reduction(Chemical), Oxidation-reduction potential, An-
aerobic conditions.
The distribution of different forms of iron in a waterlogged soil was studied
over a wide range of closely controlled redox potential and pH conditions.
increases in water soluble and exchangeable iron were favored by a decrease
in both redox potential and pH. The critical redox potentials for iron re-
duction and consequent dissolution was between +300 mV and +100 mV at pH 6
and 7, and -100 mV at pH 8, while at pH 5 appreciable reduction occurred at
+300 mV. The distribution between water soluble and exchangeable iron frac-
tions was highly pH dependent with a decrease in pH at a given redox potential
135
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increasing the relative amount of ferrous iron in the soil solution at the
expense of that on the exchange complex. A thermodynamic approach to the
equilibria between solid phase ferric oxyhydroxide and a water soluble species
of iron (Fe(+2) indicated that it was largely governed by the Fe(+2) - Fe(OH)3
system in which the ferric oxyhydroxide was a mixture of goethite and amorphous
material.
74:058-028
QUANTIFICATION OF POLLUTANTS IN AGRICULTURAL RUNOFF,
Dornbush, J,N., Andersen, J.R., and Harms, L.L.
South Dakota State University, Brookings, Department of Civil Engineering.
Environmental Protection Agency, Technology Series Report EPA-660/2-74-005,
February 1974. 149 p, 24 fig, 15 tab, 73 ref.
Descriptors: Surface runoff, *Agricultural runoff, Erosion, *Nutrients,
Phosphorus, *Nonpoint pollution source. Chemistry, Sediments, *Water pollution
sources, Pesticides, Bacteria, *South Dakota, Bioindicators, Rainfall, Snow-
melt.
Surface runoff from snowmelt and rainfall is eastern South Dakota was measured
during a three year period. The size of the research sites ranged from 7.18
to 18.69 acres, and all sites had crops of corn, oats, pasture or hayland.
Composite samples of the runoff were used for various chemical, physical and
biological determinations. Runoff samples from 108 snowmelt events and 36
rainfall events were collected. Equipment fabrication and installation re-
sulted in some incomplete data for the initial year, but successful monitoring
of each runoff event was accomplished thereafter. Sediment losses were con-
siderably lower than anticipated. Pesticide concentrations were low in both
water and sediment samples, and were usually less than the analytical test
limits. Coliform and fecal levels were consistently greater than accepted
surface water quality criteria. Most of the nutrients were found to be soluble
and/or associated with snowmelt runoff.
74:056-029
THE CHEMISTRY AND TRANSPORT OF LEAD AND CADMIUM IN SOILS,
Jurinak, J.J. and Santilian-Medrano, J.
Utah Water Research Laboratory, Logan.
Available from the National Technical Information Service, Springfield, Virginia
as PB-237 497. Research Report No. 18, June 1974, Utah Agricultural Experi-
ment Station, Logan. 121 p, 42 fig, 21 ref, append.
Descriptors: *Heavy metals, *Lead, *cadmium, *Ion transport, Leaching, Ground-
water, Industrial wastes, Soil chemistry, Phosphorus compounds, Soil contami-
nation, chemical precipitation, Water pollution sources, *Path of pollutants,
Model studies.
A one-dimensional transport model for the movement of lead (Pb) and cadmium
(Cd) ions through soils under steady state saturated moisture flow was de-
veloped. The chemical processes considered were: precipitation and dissolution,
ion-pair formation, pH formation, pH flux and adsorption or cation exchange.
The transport model was tested by data from laboratory soil columns using
three soil types. Initially both chemical equilibrium and kinetic studies
were conducted to obtain data necessary for inte-rpretive aspects of the column
studies. The main mechanism regulating Pb solubility in the nm-calcareous
soils was the precipitation of Pb5(PC4)30H, Pb3(PO4)2, and Pb(OH)2. In cal-
careaous soils, PbCO3 can also precipitate. The solubility of Cd in soils
is considerably greater than Pb in the pH range of 5 to 9. At low concen- '
trations of Cd, adsorption by soil is an important mechanism of retention.
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At higher concentrations, precipitation of Cd3(PO4)2 appears to regulate Cd
solubility. The transport model was effective in predicting Cd and Pb move-
ment in soils after the initial 20-25 pore volumes of effluent passed through
the soil column. Initial stages of transport were not accurately predicted
because of the inability of the model to accurately predict the pH flux when
the acid metal slug was added to the soil surface. The mobility of Cd in
soil was noticeably greater than that of Pb.
74:053-030
ECONOMIC EVALUATION OF THE EFFECT OF SELECTED CROP PRACTICES ON NONAGRICULTURAL
USES OF WATER,
Onishi, H., Narayanan, A.S., Takayama, T. and Swanson, E.R.
Illinois University, Urbana. Department of Agricultural Economics.
Available from the National Technical Information Service as PB-232 161.
Illinois Water Resources Center, Urbana, Research Report No. 79, March 1974.
58 p, 3 tab, 5 fig, 4 append.
Descriptors: *Water pollution sources, Evaluation, Water quality, Sedimen-
tation, Linear programming, Nitrates, Income, Crops, Illinois, Watersheds
(Basins), Path of pollutants.
Cropping systems may have an unfavorable influence on the quality of nearby
surface water. Linear programming methods were used to assess the impact of
improvements in certain water quality characteristics on economically optimal
crop systems. Thus, the effect of crop practices on water quality is analyzed
indirectly by assuming that farmers would alter their cropping practices in
the most economical way in order to conform to various water-quality con-
straints. A 1,200-acre watershed was used to illustrate the procedure. Sedi-
ment entering the reservoir was treated as a variable constraint on maxi-
mization of farm income. Requiring successively lower amounts of sediment to
enter the reservoir caused farm income to decrease at an increasing rate. The
analysis was enlarged to include a constraint on nitrate in the leachate be-
low the root zone. This phase of the analysis also included a charge for re-
moving at least some of the sediment entering the reservoir. As the nitrate
limit on the leachate was lowered, farm income decreased at an increasing
rate. The requirement of removal of the sediment by itself had little or no
effect on the nitrate concentration in the leachate. Extensions of the proT
cedure for use in other situations are suggested.
74:05B-031
DISTRIBUTION OF CONTAMINANTS IN POROUS MEDIA FLOW,
Marino, M.A.
California University, Davis, Department of Water Science and Engineering.
Water Resources Research, Vol. 10, No. 5, p 1013-1018, October 1974. 1 fig,
22 ref.
Descriptors: *Path of pollutants. Water pollution sources, *Dispersion,
*Adsorption, *Fluid movement. Porous media, Saturated flow, Groundwater move-
ment, Mass transfer, Mathematical studies, Equations, Seepage.
A mathematical analysis was presented of simultaneous dispersion and adsorption
Of a solute within homogeneous and isotropic porous media in steady unidirection-
al flow fields. The dispersion systems adsorb the solute at rates proportional
to their concentration and are subject to input concentrations that vary ex-
ponentially with time. Mathematical solutions were developed for predicting
the concentration of contaminants in adsorbing and nonadsorbing porous media
for prescribed media and fluid parameters.
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74:058-032
DIFFUSION AND DISPERSION IN OPEN CHANNEL FLOW,
Miller, A.C. and Richardson, E.V.
Pennsylvania State University, University Park, Department of Civil Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers.
Vol 100, No. HY1, Paper 10298, p 159-171. January 1974. 8 fig, 2 tab, 13 ref,
append.
Descriptors: *Diffusion, *Dispersion, *0pen channel flow, *Path of pollutants,
Mixing, Turbulence, Flow resistance
The relationships of lateral turbulent diffusion and longitudinal dispersion
coefficients to the parameters that make up the structures of flows were
studied experimentally. The resistance to flow for these runs varied from
10.6 to 4.4. The relation for the lateral turbulent diffusion coefficient
was not affected by the secondary circulation that was present in all of the
flows and is the same as that for a large range of flow conditions. The
dispersion coefficient varied with resistance to flow and the average velocity.
Longitudinal diffusion, which depends on the turbulence of the flow, was an
insignificant factor in the dispersion coefficient as compared to the distri-
bution of the local mean velocity in the lateral and vertical direction.
74:05B-033
LONGITUDINAL DISPERSION IN SATURATED POROUS MEDIA,
Marino, M.A.
California University, Davis Department of Water Science and Engineering.
Journal of the Hydraulics Division, American Society of Civil Engineers,
Vol 100, No HY1, Paper 10296, p 151-157, January 1974. 3 fig, 5 ref, append.
Descriptors: *Path of pollutants, *Groundwater movement, *Dispersion, *Porous
media, Equations, Saturated flow, Equations, Water pollution sources, Seepage
Analytical solutions were developed for two problems of longitudinal dispersion
within semi-infinite, nonadsorbing, homogeneous, isotropic media in unidirec-
tional flow fields. The source concentrations consist of variable inputs of
contaminants. The solutions predict the distribution of contaminants resulting
from the variable source concentrations. Two numerical examples are presented.
74:053-034
EVALUATION OF A SOIL NITRATE TRANSPORT MODEL,
Walter, M.F., Steenhuis, T.S., Bubenzer, G.D., and Converse, J.c.
Wisconsin University, Madison, Department of Agricultural Engineering.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 5 fig, 8 tab, 10 ref.
Descriptors: *Model studies, *Nitrates, Soil water movement, Groundwater,
Pollutants.
The potential for groundwater pollution from heavy land applications of dairy
manure is a growing concern because manure is being concentrated in smaller
areas. The worst conditions in terms of nitrate leaching to the groundwater
occur on coarse textured soils in early spring. A computer model was developed
specifically for heavy spring application of liquid dairy manure on coarse soils.
The model was used to predict nitrate movement from the application of manure on
experimental plots on a Plainfield sand and in a Piano silt loam soil column.
The computer model was designed to estimate, for specified intervals of soil
depth and time after manure application, the delay to initial nitrification of
manurial ammonium, ammonium nitrification rate, soil organic nitrogen mineral-
ization rate, nitrate dispersion, nitrate and ammonium content and soil moisture.
Precipitation and temperature data, date of manure application, ammonium
concentration of liquid manure, and quantity of manure applied must be specified
for each particular case. When the model properly simulates nitrate movement
through a soil, the results are no better than the input weather data. The
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model depends on the interrelationship between temperature and effective
precipitation over a period of several weeks or months. Input weather data
should be based on the probability of a sequence of particular weather conditions
occurring.
74:058-035
NONPOINT AGRICULTURAL POLLUTION: STATUS OF ASSESSMENT METHODOLOGY,
Aleti, A., Chiu, S.Y., and McElroy, A.D.
Midwest Research Institute, Kansas, City, Missouri.
presented at 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 2 fig, 2 tab, 27 ref.
Descriptors: *Agriculture, Pollutants, Model studies, Water quality, Water
pollution control, Water pollution sources.
Nonpoint pollution is considered to be a major deterrent to achievement of
water quality goals, and agriculture is a principal source of such pollution.
Methods for assessing and quantifying nonpoint pollution are discussed in this
paper. The overall basic need is development of comprehensive models which:
(1) include all significant pollutants, but can treat each individually; (2)
are sensitive to the causes (sources) of pollution and thus can provide the
means to develop and assess various pollution control measures and strategies;
and (3) recognize interdependencies between pollutants, such as pesticides and
sediment, in order to facilitate development of simplified control measures.
The truly comprehensive model, in useful form, is probably several years away,
so there is a continuing need to construct and use improved less-than-compre-
hensive models, and to continue the acquisition of knowledge and data needed
for progress toward effective overall models.
74:058-036
SULFUR AND MANGANESE RELEASE FROM SOILS TREATED WITH PRILLED SULFUR-BENTONITE,
Lindell, D.L. and Sornson, R.C.
Missouri University, Clinton, Department of Agronomy.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 368-372,
March-April, 1974. 3 fig, 2 tab, 10 ref.
Descriptors: Fertilization, Fertilizers, Sulfated, Sulfur, Hydrogen, Soil
properties, Soils.
Seven Nebraska soils were used to compare prilled sulfur and sulfur-bentonite
formulation in regard to the amount of sulfate-sulfur, manganese and hydrogen
released to a leaching solution after successive incubations. Also the effects
of sulfur fertilizer granule concentrations in the soil were studied. Generally,
the amount of sulfate-sulfur and manganese and the pH values in leachates from
the columns containing sulfur-bentonite were not different from those from
columns containing prilled sulfur. Differences among soils could not be ex-
plained on the basis of measured soil properties. The relationships between
the amounts of sulfate-sulfur or manganese released and percentage sulfur or
sulfur-bentonite in the soil were generally quadratic with the maximum release
occurring in the range 30 to 60% sulfur. The greatest amount of sulfur released
per gram sulfur added occurred at the lowest sulfur to soil ratio studies.
74:053-037
A STEADY-STATE MODEL OF ISOTOPIC FRACTIONATION ACCOMPANYING NITROGEN TRANSFORMA-
TIONS IN SOIL,
Shearer, G., Duffy, J., Kohl, D.H., and Commoner, B.
Washington University, St.Louis, Missouri, Center for the Biology of Natural
Systems.
Soil Science Society of America Proceedings, Vol. 38, No. 2, p 315-322, March-
April, 1974. 3 fig, 17 ref.
Descriptors: Mathematical studies, Nitrification, Ammonification, Nitrogen.
A steady-state mathematical model of isotopic fractionation accompanying certain
nitrogen transformations in soil is developed. The model takes into account
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ammonification, nitrification, and immobilization.; and predicts that the 15N/14N
ratios of nitrate and ammonium ion depend in part upon the ratio of the rates of
immobilization to nitrification under field conditions is unlikely to be the
same as under the conditions of laboratory incubation experiments. Therefore,
this prediction provides a possible explanation for differences observed between
the 15N/14N ration of nitrate extracted from soil cores and that of nitrate
released during laboratory incubation of the same soils. The model described
is ammenable to experimental test. If verified, an expanded version of the_
model may be a useful aid in the study of nitrogen transformations in the field.
74:058-038
GROUND-WATER QUALITY STUDY,
White, N.F. and Sunada, O.K.
Texaco Corporation
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 277-292, September, 1974. 6 fig, 4 tab, 9 ref,
2 append.
Descriptors: *Groundwater, Groundwater recharge, Water pollution, Water pollu-
tion sources, Water quality, Colorado, Fertilizer, Leaching, Hydrology.
Because of increasing contamination of groundwater in Colorado, a field study
was initiated of a groundwater basin showing degradation of water quality.
The basin studied was Severance Basin, located about 2 miles (3.2 km) north-
east of Windson, Colorado. In this basin, the primary source of groundwater
is percolation from irrigation. Increasing contamination in the basin
was attributed to several factors: (1) leaching of applied fertilizer; (2)
drainage from silage pits and feed lots; (3) percolation of contaminants from
oil field brine pits; (4) irrigation; and (5) geologic contamination of the
aquifer.
74:05B-039
IMPACTS OF COLORADO RIVER SALINITY,
Valantine, V.E.
Colorado River Board of California, Los Angeles.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 495-510, December, 1974. 6 tab, 9 ref.
Descriptors: Salinity, Saline soil, Saline water, Colorado River, Colorado
River basin, Salts.
Unless measures are taken to control the salinity of the Colorado River, the
average annual salinity at Imperial Dam will increase from a current level of
880 mg/1 (1968-1972) to 1,210 mg/1 in 2000, an increase of 330 mg/1: This
increase would cause deleterious impacts on irrigation and urban water users
in the states of Arizona, California, and Nevada amounting to about
$580,000,000/yr in the year 2000. The unit values of salinity detriments
were found to be $0.25/acre-ft/mg/l ($0.00002 cu m/mg/1) and $0.275/acre-ft/
mg/1 ($0.000022/cu m/mg/1) for the years 1980 and 2000, respectively. These
detriments indicate that the stake the people of the Colorado River Basin
have in measures to control the river's salinity.
74:058-040
OUTLET DRAINAGE IN ONTARIO—A METHODOLOGICAL EXPLORATION,
Kettel, G.A. and Day, J.C.
Kilborn Engineering, Ltd., Toronto, Ontario, Canada.
Journal of Environmental Management, Vol. 2, No. 4, p 331-349, October 1974.
2 fig, 4 tab, 38 ref.
Descriptors: *Drainage effects, *Drainage practices, *Drainage water, Biologi-
cal communities, Social aspects, Hydrologic aspects, Hydrologic systems.
There are considerable data which indicate that significant direct agricultural
benefits are normally induced by land drainage. However, comparatively little
is known concerning the indirect effects of this popular land management practice
on hydrological, biological, and social systems. This article focuses on outlet
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drains in Ontario which permit rapid removal of water from field tile systems
to natural water courses. Based on a review of the ability of existing
hydrologic knowledge to predict offsite drainage effects, it shows that little
research has been directed to this question. Legal and institutional arrange-
ments to cope with such unforeseen changes in Ontario are examined and both.are
found to be inadequate to prevent these kinds of damages.
74:056-041
SOURCES AND TRENDS IN WASTE WATER LOADINGS TO THE SAN FRANCISCO BAY REGION,
Breslaw, J.A.
Sir George Williams University, Montreal, Quebec, Canada, Department of
Economics,
Water Resources Research, Vol. 10, No. 6, p 1085-1089, December 1974. 3 fig, 1
tab, 9 ref.
Descriptors: *Waste water (pollution), *Pollutant identification, *Pollutants,
Water quality, Water pollution, Water pollution sources.
This study uses data obtained from the U.S. Army Corps of Engineers Permit
Program and self-monitoring data from the regional water quality control
board in an analysis of waste discharges to watercourses in the San Francisco
gay Region. The analysis shows that the majority of these discharge loads
can be attributed to a few sources. Trend analysis showed that the BOD load
has declined in relation to the quantities discharged in the early 1960's.
Nutrients, however, have increased at an annual rate of about 4% since the
early 1960's.
74:058-042
A SURVEY OF THE BORON CONTENT OF CERTAIN WATERS OF THE GREATER LONDON AREA
USING A NOVEL ANALYTICAL METHOD,
Matthews, P.J.
Directorate of Scientific Services, Anglian Water Authority, Diploma House,
Huntingdon.
The Journal of the International Assdciation on Water Pollution Research, Vol.
8, No. 12, p 1021-1028, December, 1974. 1 fig, 7 tab, 23 ref.
Descriptors: *Boron, *Aquatic environment, *Sewage, *Sewage effluents, *Analyt-
ical techniques, Water quality, Water pollution.
Natural levels of boron, (as boric acid), in the aquatic environment have been
raised artificially in certain areas by sewage effluents. Boron is present in
sewage effluent by virtue of the use of sodium perborate as a whitener in
washing powders. A novel analytical method based on the solvent extraction of
ferroin borodisalicylate was used in a survey of various types of sewage,
sewage effluent and natural waters in the London area. The method was found
to be satisfactory under all conditions. The data obtained will be useful
in water resource planning and indicated that the concentration of boron in
watercourse may be used, under certain conditions, to determine the degree
of dilution of sewage effluent in that watercourse.
74:058-043
PHYSICAL AND CHEMICAL QUALITY OF AGRICULTURAL LAND RUNOFF,
Harms, Leland L., Dornbush, James N., and Anderson, John R.
South Dakota State University, Brookings.
journal of the Water Pollution' Control Federation, Vol. 46, No. 11, p. 2460-
2470, November, 1974. 3 fig, 7 tab, 23 ref.
Descriptors: *Runoff, *Water chemistry, Water pollution, Water pollution sour-
ces, Water properties, Water quality, Erosion, Rainfall, Snowmelt, Phosphorus,
Nutrients.
considerable quantities of nutrients were present in the agricultural runoff,
and these would seem to have important implications regarding the possible
occurrence of eutrophic conditions in water impoundments. Nutrient losses
averaged about 1 Ib/yr/acre (1.12 kg/yr/ha) for nitrogen and about 0.2 lb/yr/
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acre (0.2 kg/yr/ha) for phosphorus. The nutrient form is also of consequence.
Most of the annual nutrient load for the area studied came from snowmelt run-
off, and a large percentage was soluble. Soil conservation practices will
probably not be effective measures for retarding lake eutrophication from
the nutrients in agricultural runoff. The annual soil losses were much lower
than expected, most of the sediment originating from cultivated fields. The
bulk of the soil losses, as well as losses of those constituents associated
with the soil, occurred during short duration, high intensity rain storms.
Almost all of the soil lost during the study may be attributed to rainfall
runoff.
74:05B-044
DIFFERING SENSITIVITY OR CORN AND SOYBEAN PHOTOSYNTHESIS AND TRANSPIRATION TO
LEAD CONTAMINATION,
Bazzaz, F.A., Rolfe, G.L. and Windle, P.
Illinois University, Urbana.
Journal of Environmental Quality, Vol. 3, N6. 2, p 156-158, April-June, 1974.
3 fig, 15 ref.
Descriptors: *Heavy metals, *Pollution, *Crop response, *Lead, Corn, Soybean,
Photosystems, Transpiration.
Corn plants grown in media containing a range of Pb concentrations supplied as
PbCl(2), showed decreased net photosynthesis and transpiration with increasing
Pb treatment levels. At lower Pb treatment levels, corn appears to be more
sensitive than soybeans. However, at high treatment level (62.5-250 mg/plant)
soybeans are more sensitive than corn. At 250 mg Pb/plant in the medium,
photosynthesis is only 10% of maximum in soybeans but 47% in corn, even though
corn Pb tissue content is much higher than that of soybeans. Transpiration ex-
hibited similar trends to photosynthesis suggesting that, especially in corn,
an appreciable part of the inhibition of the two processes is related to
increased stomatal resistances with increased Pb concentrations. Lead accumu-
lation trends were similar at treatment levels of 0 to 62.5 mg/plant but were
slightly different at higher levels. The total amount of Pb accumulated was
higher in corn than in soybeans. Maximum accumulation in both species occurred
at 62.5 mg Pb/plant.
74:058-045
OCCURRENCE OF 2,4,5-T AND PICLORAM IN SURFACE RUNOFF WATER IN THE BLACKLANDS
OF TEXAS,
Bovey, R.W., Burnett, E., Richardson, C., Merkle, M.G., Jr., and Baur, J.R.
United States Department of Agriculture, College Station, Texas, Agricultural
Research Service.
Journal of Environmental Quality, Vol. 3, No. 1, p 61-64, January-March, 1974.
8 tab, 12 ref.
Descriptors: *Herbicides, Watersheds (basins), Watershed management, Runoff,
Range management.
This investigation was conducted to determine the concentration of 2,"4^5-T
and picloram in surface runoff water that may move from herbicide sprayed
pastures and rangeland to untreated areas as a result of each major rainfall
following treatment. A 1:1 mixture of the triethylamine salts of 2,4,5-T +
picloram was sprayed 5 times at 1.12 kg/ha every 6 months on a native-grass
pasture watershed. Soil, grasses and runoff water were analyzed periodically
following herbicide treatment. Herbicide content in the Houston Black clay
from May 1970 to May 1972 remained low (o to 238 ppb). Herbicide content
on grass was high (50 to 70 ppm) immediately after treatment, but degraded
rapidly thereafter. Plant "washoff was the main source of herbicide detected
in runoff water. Concentration of herbicide was moderately high (400 to
800 ppb) if heavy rainfall occurred immediately after treatment, but low
(<5 ppb) if major storms occurred 1 month or longer after treatment.
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74:058-046
NUTRIENT LOSSES FROM FERTILIZED GRASSED WATERSHEDS IN WESTERN NORTH CAROLINA,
Kilmer, V.J., Gilliam, J.W., Lutz, J.F., Joyce, R.T. and Eklund, C.D.
Tennessee Valley Authority, Muscle Shoals, Alabama, Soils and Fertilizer
Research Branch.
Journal of Environmental Quality, Vol. 3, No. 3, p 214-218, July-September,
1974. 1 fig, 7 tab, 29 ref.
Descriptors: *Nutrients, *Nitrogen, *Phosphorus, *Potassium, Runoff, Water
quality, Groundwater, Drainage, Fertilizers, Fertilization, North Carolina.
The transport of plant nutrients in drainage waters from two steeply sloping,
differentially fertilized, grassed watersheds located in western North Carolina
was determined over a 4-year period. Watershed No. 1 has a drainage area of
1.89 ha, No. 2, 1.48 ha. The dominant slopes on both watersheds are 35 to 40%.
During this period, watershed No. 1 received a total of 112-48-24 kg N-P-K/ha;
watershed No. 2 received 448-192-24 kg N-P-K/ha. Average annual measured N
losses were 3.28 and 12.08 kg/ha for watershed No. 1 and watershed No. 2,
respectively; NO(3)-N comprised 70% and 85% of the total N lost in discharge
waters from the two watersheds. Total N lost over the 4-year period from
each watershed was 6 to 10% of the fertilizer N applied. Annual P losses
were negligible, amounting to 0.15 kg/ha from watershed No. 1 and 0.27 kg/ha
from watershed No. 2. Measured K losses averaged 3.99 and 5.83 kg/ha annually;
S losses were 1.92 and 2.54 kg/ha from watershed No. 1 and watershed No. 2 re-
spectively.
74:05B-047
LAND SURFACE EROSION AND RAINFALL AS SOURCES OF STRONTIUM-90 IN STREAMS,
Menzel, R.G.
United States Department of Agriculture, Durant, Oklahoma, Agricultural
Research Service, Water Quality Management Laboratory.
journal of Environmental Quality, Vol. 3, No. 3, p 219-223, July-September,
1974. 4 fig, 2 tab, 23 ref.
Descriptors: *Runoff, *Erosion, *Strontium, *Streams, Water quality, Pollution,
Radioactivity, Pesticides, Correlation analysis.
Strontium-90 concentrations in streams from 1958 to 1967 reflected the
changing concentrations in rainfall and accumlation on the land surface.
Correlation analysis of data from nationwide sampling networks shows that
the Sr-90 concentration in streams was accounted for, on the average, by
1.7% of the rainout 2 months earlier, and annual erosion of 0.58% of the
accumulated Sr-90 on the land surface. Direct runoff of Sr-90 in preceding
rainfall was highest, 2.0 to 2.2%, in the north central and eastern United
States, ranging down to no measurable direct runoff in the southwestern
United States. Annual erosion of Sr-90 from the land surface ranged from
0.75% in the Ohio River Basin to 0.17% in the Missouri River Basin. If one
allows for differences in time and area of application, these results for
land surface erosion indicate the potential movement of persistent, strongly
adsorbed pesticides from large land areas.
74:058-048
UPTAKE OF INORGANIC MERCURY BY BED SEDIMENTS,
Kudo, A., and Hart, J.S.
journal of Environmental Quality, Vol. 3, No. 3, p 273-278, July-September,
1974. 7 fig, 21 ref.
Descriptors: *Mercury, Rivers, Sediments, Kinetics, Water quality, Water
pollution.
Tne kinetics of uptake of inorganic mercury as mercuric chloride by a variety
f freshwater river sediment types typical of Ottawa River sediments were
studied to determine the influence of mercury concentration in water, hydro-
dynamic effects, sediment depth, aerobic or anaerobic conditions, and two
types of water. Uptake appears to depend strongly on concentration of mer-
cury i° wafcer and water velocity, and not on sediment depth or water type.
NO significant difference in uptake rates was observed between aerobic and
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anaerobic conditions during the 10 days studied.
74:058-049
PHOSPHORUS ASSOCIATED WITH SEDIMENTS IN IRRIGATION AND DRAINAGE WATERS FOR
TWO LARGE TRACTS IN SOUTHERN IDAHO,
Carter, D.L., Brown, M. J., Robbins, C.W., and Bondurant, J.A.
Snake River Conservation Research Center, Kimberly, Idaho.
Journal of Environmental Quality, Vol. 3, No. 3, p 287-291, July-September,
1974. 5 tab, 18 ref.
Descriptors: *Phosphorus, Irrigation water. Drainage water, Irrigation
practices, Erosion, Sediments, Water quality, Water pollution.
Phosphorus was measured in irrigation and surface drainage waters for two
large irrigation tracts, and inorganic, water-soluble PO(4)-P and total P
inputs and outputs were computed. The present irrigation practices on both
irrigation tracts conserve P by removing more P from the Snake River in
irrigation water than is returned in drainage water. Even greater P con-
servation could be attained by implementing new practices. Approximately
90% of the P in waters diverted to irrigate the Northside Tract remained
in the tract. About 50% of the amount diverted remained in the Twin Falls
Tract. Particle size segregation takes place in some drainage streams and the
finer sediments returning to the river contain higher total and NaHCO(3)-
extractable P concentrations than the soils from which they were eroded.
74:058-050
NITRATE AND CHLORIDE MOVEMENT IN THE PLAINFIELD LOAMY SAND UNDER INTENSIVE
IRRIGATION,
Endelman, F.J., Keeney, D.R., Gilmour, J.T., and Saffigna, P.G.
Wisconsin University, Madison, Department of Chemical Engineering.
Journal of Environmental Quality, Vol. 3, No. 3, p 295-298, July-September,
1974. 5 fig, 2 tab, 11 ref.
Descriptors: *Fertilization, *Fertilizer, *Nitrates, *Nitrogen, *Leaching,
Irrigation practices, Irrigation, Groundwater, Pollution, Water quality, Soil
properties, Lysimeters, Chlorides.
A field experiment to evaluate leaching under intensive irrigation was con-
ducted over an 11-day period on a Plainfield loamy sand fertilized with KNO(3)
and KCL. The NO(3)-N and Cl concentration in soil profile and lysimeter
leachate samples collected daily were determined. Under the conditions of
this experiment 2.5 cm of water moved about 19 cm in the surface and 28 cm
in the subsurface soil. Chloride concentrations in the profiles were similar
to those of NO(3)-N. Movement of NO(3)-N and Cl was 15 to 20 cm/day under
2.5 cm daily water application. The results show that rainfall and/or irri-
gation, can rapidly move NO(3)-N beyond the rooting zone of this soil.
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74:05B-051
PLANT NUTRIENT LOSSES FORM TILE-OUTLET TERRACES,
Hanway, J.J. and Laflen, J.M.
Iowa State University, Ames, Department of Agronomy.
Journal of Environmental Quality, Vol. 3, No. 4, p 351-356, October-December,
1974. 3 fig, 4 tab, 13 ref.
Descriptors: *Nutrient removal, *Nutrients, *Phosphorus, Tile drainage,
Sediment, Nitrogen, Nitrification, Sulfur, Runoff, Fertilizer, Fertilization.
Plant nutrient losses in runoff water from four tile-outlet terrace systems
in Iowa and in tile drainage from two of the systems were measured annually
from April to November over a 3-year period. Soluble P concentrations in
surface runoff were related to available P in the surface soils, and concen-
trations in tile drainage were related to available P in the subsoils. Con-
centrations of inorganic N varied widely among locations, but were relatively
constant at a location. Average annual inorganic N concentrations in surface
runoff were 4 ppm or less at three of the four sites and 11 ppm at one site.
Concentrations of inorganic N and sulfate S were similar and were lower
in surface runoff than in tile drainage. There was no relation between the
amounts of fertilizer applied and plant nutrient losses or concentrations in
runoff or drainage water.
74:058-052
PRECIPITATION NITROGEN CONTRIBUTION RELATIVE TO SURFACE RUNOFF DISCHARGES,
Schuman, G.E. and Burwell, R.E.
United States Department of Agriculture, Lincoln, Nebraska.
journal of Environmental Quality, Vol. 3, No. 4, p 366-369, October-December,
1974. 1 fig, 4 tab, 12 ref.
Descriptors: *Nitrates, *Ammonia, Runoff, Watershed management, Water quality,
Precipitation, Water pollution, Nutrient removal.
Ammonia and nitrate concentrations in precipitation and surface runoff from
two adjacent watersheds, fertilized at 168 and 448 kg N/ha, respectively,
were studied to determine the relative contributions of precipitation N
in relation to surface runoff N discharge. The data show that 69% of the N
discharged by surface runoff from the sampled events could be accounted for
by precipitation-originated N on the watershed fertilized at 168 kg N/ha,
whereas 53% of the N discharged from the watershed fertilized at 448 kg N/ha
could be a attributed to N originating in the precipitation. However, the data
indicate that, on an annual basis, the surface runoff N discharge accounts for
only 20% of that in the total incoming precipitation. This difference can be
accounted for by precipitation intensity or duration that did not cause runoff,
absorption of NH(4)-N by the soil material, or leaching of NO(3)-N into the
soil profile.
74:05B-053
FATE OF INSECTICIDES IN AN IRRIGATED FIELD: AZINPHOSMETHYL AND TETRADIFON
CASES,
Yaron, B. Bielorai, H., and Kliger, L.
Institute of Soils and Water, ARO, Volcani Center, Bet Dagan, Israel, Division
of Soil Residue Chem.
journal of Environmental Quality, Vol. 3, No. 4, p 413-417, October-December,
1974. 7 fig, 7 ref.
Descriptors: *Pesticides, *Pesticide removal, *Pesticide residues, "-Leaching,
irrigation practices, Soil water movement, Potato.
The fates of an organophosphorus and an organochlorine insecticide in an
irrigated potato field on a loessial sierozem soil were studied. Two amounts
of irrigation water (5538 and 4015 cu m/ha) were applied; the kinetics of
persistence and the movement downward of the two pesticides were followed
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during the irrigation season. The azinphosmethyl was not transported deeply
into the soil by the irrigation water, and it disappeared from the field 30
days after application. The tetradifon was found in trace amounts in the
deeper layer of the soil and was persistent throughout the irrigation season.
The pesticides' persistence was not affected by the irrigation treatments;
however, tetradifon transport into the soil was affected by the amount of
water applied. Residues of tetradifon were found in the potato peel.
74:058-054
NITROGEN CONTENT OF SHALLOW GROUND WATER IN THE NORTH CAROLINA COASTAL PLAIN,
Gilliam, J.W., Daniels, R.B., and Lutz, J.F.
North Carolina State University, Department of Soil Science.
Journal of Environmental Quality, Vol. 3, No. 2, p 147-151, April-June, 1974.
2 fig, 2 tab, 14 ref.
Descriptors: *Nitrates, *Nitrogen, Groundwater, *Denitrification, Cultivation,
Wells, Aquifer, North Carolina.
The NO(3)-N and NH(4)-N concentrations in shallow (<3 m) ground water under
a range of soil types, drainage conditions, and type of crop grown were mon-
itored. The NO(3)-N levels were always low (1 ppm or less) in ground water
under wooded areas. The concentrations were somewhat higher under cultivated
fields with the levels usually being 1 to 5 ppm although several values in the
range of 10 to 20 ppm were recorded. The concentrations in all wells were
always higher during the winter months. There seemed to be no relationship
between cultivated crop and NO(3)-N in the ground water. The NO(3)-N con-
centration was almost always higher in the middle of the field than was
toward the edge of the field. It is suggested that denitrification is
responsible for this decrease. Based upon the characteristics of the sur-
face sediments, it is concluded that very little of the NO(3)-N present in
the shallow ground water moves into deep aquifers in any area of the North
Carolina Coastal Plain. However, the amount of NO(3)-N that moves through the
surficial sediments to the streams probably varies with location and charact-
eristics of the confining beds.
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Section XVIII
WATER QUALITY MANAGEMENT AND PROTECTION
EFFECTS OF POLLUTION (Group 05C)
74i05C-001
THE PHOSPHORUS STATUS OF EUTROPHIC LAKE SEDIMENTS AS RELATED TO CHANGES IN
LIMNOLOGICAL CONDITIONS—TOTAL, INORGANIC AND ORGANIC PHOSPHORUS,
Wildung, R.E., Schmidt, R.L. and Gahler, A.R.
Battelle-Pacific Northwest Laboratory, Richland, Washington.
journal of Environmental Quality, Vol. 3, No. 2, p 133-138, April-June 1974.
2 fig, 3 tab, 19 ref.
Descriptors: Sampling, *Phosphorus, *Sediments, *Eutrophication, *Lakes,
Carbon, *Nitrogen, Organic matter, Phytoplankton, Runoff, Biological com-
munities, Surface waters, Turbidity, Water pollution effects, *Oregon, *Lake
sediments.
The role of sediments as a source of phosphorus to lake waters and the factors
which may influence sediment phosphorus release were studied. Changes with
time in the phosphorus status of noncalcareous sediments of a eutrophic lake
were related to changes in sediment carbon and nitrogen, surface water com-
position, pH, temperature, and phytoplankton growth. Sediment phosphorus
status and the relationship of these changes to limnological conditions dif-
fered with locations in the lake. Changes in sediment composition were great-
est in a bay which received agricultural runoff in the early spring, additional
nutrients apparently providing the initial impetus for increased surface water
biological activity. This was reflected in increased surface water organic
carbon and nitrogen, turbidity, and phytoplankton growth. At this location,
total sediment phosphorus, carbon, and nitrogen decreased during the late
spring and early summer, corresponding to the period of exponential growth of
the lake phytoplankton population. Results indicate that sediment inorganic
phosphorus is directly related to the biological productivity of the surface
waters, and in at least one location, sediments serve as a significant source
of phosphorus to these waters supporting increased biological growth.
74:05C-002
ECONOMIC DAMAGES FROM RESIDENTIAL USE OF MINERALIZED WATER SUPPLY,
Tihansky, D.P.
Environmental Protection Agency, Washington, D.C., Economic Analysis Division
Water Resources Research, Vol. 10, No. 2, p 145-154, April 1974. 8 fig 5
tab, 38 ref.
Descriptors! *Water quality, *Domestic water, *Damages, Public health, Scaling,
Corrosion, Economics, Abrasion, *Costs, Plumbing, *Computer programs. Clogging.
Household appliances and personal items in contact with water supplied munici-
pally or from private sources are subject to physical damages from chemical
and other constituents of the water. Economic losses are calculated for a
typical household and aggregated to the national and individual state levels
The types of physical damages expected and the associated water quality de-
terminants were identified, and the physical effects were then translated
into economic losses. Damage functions were formulated to predict likely
impacts of water quality changes on each household unit affected. A computer
program based on these functions was designed to estimate total damages per
typical household and to aggregate them over selected regions. The program
was applied to state-by-state data describing water supply sources andlocio-
economic parameters. Total annual damages to U.S. residents in 1970 were
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estimated to be in the range $0.65-$3.45 billion, the mean being $1.75 billion.
The mean translates to $8.60 per person annually. States having the highest
total damages were California ($230 million) and Illinois ($164 million). On
a per capita basis, Arizona ($22.53) and New Mexico ($18.58) ranked highest,
whereas South Carolina ($1.15) and Oregon ($1.73) were at the other end of the
spectrum. When per capita damages were compared by source of water supply,
private wells were highest at an average of $12.34, treated groundwater was
next at $11.20, and treated surface water was last at $5.83.
74:05C-003
A SOLUTION OF THE INORGANIC CARBON MASS BALANCE EQUATION AND ITS RELATION TO
ALGAL GROWTH RATES,
Kelly, M.G., Church, M.R. and Hornberger, G.M.
Virginia University, Charlottesville, Department of Environmental Sciences.
Water Resources Research, Vol. 10, No. 1, p 493-497, 1974. 2 fig, 1 tab, 18
ref.
Descriptors: *Equations, *Carbon, *Carbon dioxide, *Algae, Mathematical
studies, Growth rates, Biological communities, Productivity, Groundwater,
Rivers, Lakes, Biomass, Eutrophication.
It is interesting to know under what natural conditions carbon dioxide con-
centrations might be low enough to influence algal growth rates. Even if low
carbon concentrations do not prevent cultural eutrophication, they could well
influence the relative growth of different species. Equations describing the
concentrations of the various inorganic carbon species in relation of pH and
alkalinity may be combined with a chemical mass balance equation describing the
rate of change of total inorganic carbon in a river due to photosynthesis,
respiration, accrual from groundwater, and exchange with the atmosphere. The
mass balance equation is solved to give carbon dioxide concentration throughout
the day. Without accrual of groundwater the carbon dioxide concentration must
lie in the range where it will influence growth rate of some plant species,
but groundwater input prevents this situation in most rivers. In lakes, ground-
water input and exchange with the aphotic zone may prevent the influence of
carbon dioxide on algal growth rates. In waters with little groundwater in-
put or little vertical mixing the carbon dioxide concentration may influence
relative growth rates of species and thus the community composition but
probably not the total plant biomass produced.
74:05C-004
INORGANIC NITROGEN REMOVAL IN A COMBINED TERTIARY TREATMENT - MARINE AQUACUL-
TURE SYSTEM - II. ALGAL BIOASSAYS,
Goldman, J.C., Tenore, K.R., and Stanley, H.I.
Woods Hole Oceanographic Institution, Massachusettes
Water Research, Vol 8, No 1, p 55-59, 1974. 3 fig, 2 tab, 9 ref.
Descriptors: *Waste water treatment, *Bioassays, Sampling, *Tertiary treatment,
Discharge (Water), *Nitrogen, *Algal control, Waste water (Pollution), Coasts
Algal bioassays, conducted on samples from various conponents of the combined
tertiary treatment-marine aquaculture process, demonstrated that nitrogen
removal is necessary to prevent increasing the algal growth potential of
coastal marine waters receiving wastewater discharges. When nitrogen was
removed from secondarily treated domestic wastewater, the wastewater in
varying dilutions with seawater could not support more algal growth than the
seawater alone. By adding nitrogen back to the treated wastewater the algal
growth potential was increased to that of the untreated wastewater. This was
demonstrated by assaying samples containing both artificially added nitrogen
and nitrogen regenerated by oysters. Assays of the effluent from the seaweed
system showed that the removal of regenerated nitrogen reduced the algal
growth potential to that of natural seawater.
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74:05C-005
ENVIRONMENTAL ASPECTS OF AQUATIC PLANT CONTROL,
Hartley, T.R. and Gangstad, E.O.
Bureau of Reclamation, Denver, Colorado, Environmental Science Section,
Division of General Research.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 231-244, September, 1974. 4 fig, 2 tab, 17
ref.
Descriptors: Aquatic environment, Aquatic life, Aquatic plants, Aquatic weed
control, Aquatic weeds, Herbicides.
Detailed studies on the environmental aspects of aquatic control with aquatic
herbicides do not preclude their use when properly selected and properly
applied. Residues in the water under the conditions stated, do not preclude
the use of this water for irrigation of crop plants or potable use of the
water.
74:05C-006
IMPACTS OF COLORADO RIVER SALINITY,
Valantine, V.E.
Colorado River Board of California, Los Angeles.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 495-510, December, 1974. 6 tab, 9 ref.
(See 74:05B-039)
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Section XIX
WATER QUALITY MANAGEMENT AND PROTECTION
WASTE TREATMENT PROCESSES (Group 05D)
74:05D-001
SITE EVALUATION AND DESIGN OF SEEPAGE FIELDS,
Healy, K.A. and Laak, R.
Connecticut University, Storrs, Department of Civil Engineering.
Journal of the Environmental Engineering Division, American Society of Civil
Engineers, Vol. 100, No. EE5, Proceedings Paper 10882, p 1133-1146, October
1974. 7 fig, 2 tab, 15 ref, 3 append.
Disposal, Percolation, water pollution sources, water pollution, Acsorpti
Permeability, Waste water disposal, Subsurface drainage. Tiles, Hydraulic
r-onriiir--t--ivitv. Effluents, Environmental enaineerina.
A reevaluation of previous work by others indicated that soil can absorb
septic tank effluent indefinitely if the application rate is kept below a
certain level, which is a function of soil permeability. This long-term
acceptance rate is independent of whether the soil is continuously or intermit-
tently flooded, and varies from approximately 0.3 gpd/sq ft (0.01 m/day) for
clay loam and silt to approximately 0.8 gpd/sq ft (0.03 m/day) for sand.
Study of the groundwater flow pattern below a seepage field showed that it is,
in many cases, the hydraulic conducitivty of the ground surrounding the field,
as determined by the external water table, soil permeability, and impervious
strata, that controls the size of the field required. These three factors
were determined by a test pit dug at seven sites in the Mansfield, Connecticut
area. Pit permeability tests were developed and results compared favorably
with tube sample permeameter tests. Based on the information obtained, a
chart was prepared to aid in designing a seepage field. Two design examples
were included.
74:050-002
INORGANIC NITROGEN REMOVAL IN A COMBINED TERTIARY TREATMENT - MARINE AQUACUL-
TURE SYSTEM — I. REMOVAL EFFICIENCIES,
Goldman, J.C., Tenor, K.R., Ryther, J.H. and Corwin, N.
Woods Hole Oceanographic Institution, Massachusettes
Water Research, Vol 8, No 1, p 45-54, 1974. 5 fig, 6 tab, 34 ref.
Descriptors: *Recycling, Water conservation, Water pollution treatment, *Water
reuse, Sewage treatment, *Tertiary treatment, *Food chains, *Food webs,
Ecosystems, Algae, Oysters, Nitrogen, *Waste water treatment, *Phosphorus.
The transformation of nitrogen and phosphorus were observed during the Summer
and Fall of 1972 in a prototype process consisting of growth systems for
marine algae, oysters, and seaweed, joined in series and fed secondarily-
treated waste-water diluted 1:4 with seawater for 11 weeks. During this time
95% of the influent inorganic nitrogen was removed by algal assimilation. The
oysters in turn removed 85% of the algae, but regenerated as soluble ammonia
16-18% of the nitrogen originally bound in the algal cells. All of the
regenerated nitrogen was removed in the seaweed system so that the total
inorganic nitrogen removal efficiency of the system was 95%. Phosphorus
removal was not nearly as complete as only 45-60% was removed. The process
has the capability of being expanded to include additional trophic levels in
an integrated and highly controlled food chain system to serve the dual function
of tertiary wastewater treatment and waste recycling through the production of
shellfish and seaweeds.
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74:050-003
THE DEVELOPMENT OF A CENTER PIVOT WASTEWATER IRRIGATION MACHINE,
HBll, G.W.
Metropolitan Sanitary District of Greater Chicago, Canton, Illinois.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 5 fig, 2 tab, 7 ref.
Descriptors: *Sprinkler irrigation, *Waste water disposal, Application methods,
Application equipment, Irrigation practices, Irrigation water, Irrigation,
Irrigation systems.
The center pivot irrigation industry continues to improve its product each year.
Problem areas highlighted by a testing program were corrected and incorporated
into the manufacturers model changes for the next year. Probably the most
important difference between a conventional center pivot irrigation machine and
a wastewater center pivot irrigation machine is the spray bar concept. The low
operating pressure requirement provides a lower operating cost because of lower
pumping costs. However, the high instantaneous application rate of the spray
bar concept limits its application to areas where the soil has a high intake
rate if surface runoff is minimized. The center pivot wastewater irrigation
machine will continue to be a modified conventional center pivot irrigation
machine until the wastewater market developes to the point where the center
pivot industry begins to conduct research and development programs. The goal
of the wastewater industry and the agricultural industry is the same and that is
to have an economical, dependable irrigation machine.
74:050-004
NITRIFICATION RATE IN BIOLOGICAL PROCESSES,
Huang, C.S. and Hopson, N.E.
Metcalf and Eddy, Incorporated, Boston, Massachusetts.
Journal of the Environmental Engineering Division, Vol. 100, No. EE2 p 409-
422, April 1974. 3 fig, 78 ref, 2 append.
Descriptors: *Nitrification, Rates, Sanitary engineering, Biological proper-
ties, Laboratory tests.
A review of literature concerning the nitrification process shows a diverse
opinion as to the reaction rate equation for the process. Four reaction rate
equations are reviewed and an experimental study performed to determine the
correct equation. From the initial ammonia nitrogen concentration and the con-
tact time studies the nitrification process was shown to follow a zero-order
reaction. This conclusion is in disagreement with some of the reviewed liter-
ature. However, many experimental and evaluation problems may cause researchers
to assume first-order reaction rates in their nitrification studies The
expression "percent removal" or "percent remaining" usually used in BOD reac-
tions is not a meaningful way to evaluate the reaction rate. A small change
in pH caused by the H+ ions released from the nitrification process also
may affect the results of nitrification studies.
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Section XX
WATER QUALITY MANAGEMENT AND PROTECTION
WATER QUALITY CONTROL (Group 05G)
74:05G-001
EVALUATION OF IRRIGATION SCHEDULING FOR SALINITY CONTROL IN GRAND VALLEY,
Skogerboe, G.V., Walker, W.R., Taylor, J.H. and Bennett, R.S.
Colorado State University, Fort Collins, Department of Agricultural Engineering.
Environmental Protection Agency, Technology Series Report EPA-660/2-74-052,
June 1974.
Descriptors: Colorado River, *Deep percolation, Irrigation, Irrigation effects,
*Irrigation efficiency, Irrigation water, *Return flow, Saline soils, Saline
water, Salinity, Water distribution(Applied), Water loss, Water pollution
sources, Water quality, *Colorado.
Although the results of this study indicate that existing programs for irri-
gation scheduling in the Grand Valley to control salinity are having only a
marginal effect, the potential for 'scientific' irrigation scheduling has been
well established. Also, irrigation scheduling should not be taken individually
as a salinity control measure because its effectiveness is not exclusive of
the operation of the total irrigation system. Thus, irrigation scheduling is
a necessary, but not sufficient, tool for achieving improved irrigation effi-
ciencies. The real strides in reducing the salt pickup resulting from over-
irrigation will come from the employment of scientific irrigation scheduling
in conjunction with improved on-farm irrigation practices. This combined ef-
fect could result in a reduction of 300,000 tons annually of salt pickup from
the Grand Valley, depending upon the degree of improvement in present on-farm
irrigation practices.
74:050-002
THE LONG-RUN ASYMMETRY OF SUBSIDIES AND TAXES AS ANTIPOLLUTION POLICIES,
Porter, R.C.
Michigan University, Ann Arbor, Department of Economics.
Water Resources Research, Vol. 10, No. 3, p 415-417, June 1974. 1 tab, 11 ref.
Primers on the discharge of unwanted but unpriced effluents into the air and
water now treat as commonplace the symmentry between taxes on effluents and
subsidies for abatement as means of reducing an industry's pollution. This
note shows that on the contrary, serious asymmetry results when entry and
exit occur in response to subsidies or taxes. Not only does the quantitative
symmetry disappear, but even the qualitative impact (the directions of the
effects) of charges and bribes on the volume of firm and industry effluents
may differ. More specifically, the possibility emerges than an abatement
subsidy offered to an industry may increase the total effluents of that in-
dustry.
74:05G-003
DEVELOPMENT OF SALINITY CONTROL TECHNOLOGY IN GRAND VALLEY,
Skogerboe, G.V., Walker, W.R., Bennet, R.S., and Taylor, J.H.
Colorado State University, Fort Collins, Department of Agricultural Engineering.
Presented at the 1974 Annual Meeting of the American Society of Agricultural
Engineers, June 23-26, 1974. Stillwater, Oklahoma. 8 fig, 5 ref.
Descriptors: *Saline soils, *Saline water, Salinity, Technology, Irrigation,
Agriculture, Colorado, Irrigation operation and management.
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Research recently undertaken will evaluate the effects of various irrigation
water management practices on the chemical quality of subsurface return flows
as well as crop yields. The results of this effort will allow predictions of
chemical quality in the Colorado River when various salinity control measures
are implemented.
74:05G-004
AGRICULTURAL WASTE MANAGEMENT
Committee on Agricultural Waste Management of the Environmental Engineering
Division.
journal of the Environmental Engineering Division, Vol. 100, No. EE1,
p. 1-6, February, 1974. 1 fig.
(See 74:04A-011)
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Section XXI
WATER RESOURCES PLANNING
TECHNIQUES OF PLANNING (Group 06A)
74:06A-001
APPLICATION OF SEASONAL PARAMETRIC LINEAR STOCHASTIC MODELS TO MONTHLY FLOW
DATA,
McKerchar, A.I. and Delleur, J.W.
Purdue University, Lafayette, Indiana, School of Civil Engineering.
Water Resources Research, Vol. 10, No. 2, p 246-255, April 1974. 6 fig, 2
tab, 16 ref.
Descriptors: *Hydrologic aspects, *Flow data, *Model studies, Forecasting,
Mathematical studies, *Seasonal, Hydrologic data, Logarithms.
Stochastic linear models are fitted to hydrologic data for two main reasons:
to enable forecasts of the data one or more time periods ahead and to enable
the generation of sequences of synthetic data. Short sequences of data lead
to uncertainties in the estimation of model parameters and to doubts about
the appropriateness of particular time series models. A premium is placed on
models that are economical in terms of the number of parameters required.
One such family of models is multiplicative seasonal autoregressive integrated
moving average (Arima) models. Illustrated is the process of identifying the
particular member of the family that fits logarithms of monthly flows, esti-
mating the parameters, and checking the fit. The seasonal Arima model ac-
counts for the seasonal variability in the monthly means but not the seasonal
variability of the monthly standard deviations: for this reason its value
is limited. The forecasting of flows one or more months ahead is described
with an example.
74:06A-002
IMPROVED DYNAMIC PROGRAMMING PROCEDURES AND THEIR PRACTICAL APPLICATION TO
WATER RESOURCE SYSTEMS,
Mawer, P.A. and Thorn, D.
Water Research Association, Marlow, England.
Water Resources Research, Vol. 10, No. 2, p 183-190, April 1974. 9 fig, 2
tab, 10 ref.
Descriptors: Water resources development, *Dynamic programming, *Simulation
analysis, *Reservoirs, *Long-term planning, *0peration, Optimization, Algorithms,
Probability, Markov processes, Reliability, Water demand, Water supply, Pump-
ing plants, Inflow, Rivers, Decision making, Operations research, Mathematical
models.
An optimization algorithm is described that uses value iteration dynamic pro-
gramming and simulation in conjunction with penalty costs to derive long-term
operating policies for water resource systems. Feedback from the simulation
to the dynamic programming is achieved by means of the penalty costs, which
may be interpreted as Lagrangian multipliers. Highly efficient value iteration
procedures are developed for two types of problems illustrated by numerical
examples: (1) deterministic transition costs—an on-channel reservoir is to
be operated in conjunction with a high cost source; and (2) probability tran-
sition costs—herein considers the supply of water to a pumped storage reservoir
used for amenity purposes and direct regulated water demands. Both problems
require finding an operating policy that minimizes long-term running costs
and satisfies a reliability objective; the latter problem requires also ful-
filling an amenity objective. An indication is given of how the methods
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described can be applied to multireservoir systems by using the concept of
an equivalent reservoir. It is shown that simplified dynamic programming pro-
cedures can be formulated by recognizing the inherent nature of the problem
and neglecting such things as the serial correlation of reservoir inputs.
These procedures produce substantial savings in computation, enabling a much
more thorough appraisal of problems than was hitherto possible. Although
slightly suboptimal operating policies are obtained, the practical benefits
obtained from the general optimization algorithm outweigh most theoretical
objections.
74:06A-003
MULTIPLE-OBJECTIVE OPTIMIZATION IN WATER RESOURCE SYSTEMS,
Vemuri, V.
Purdue University, Lafayette, Indiana, Department of Electrical Engineering.
Water Resources Research, Vol. 10, No. 1, p 44-48, February 1974. 2 fig, 1
tab, 8 ref.
Descriptors: Water resources, *Planning, ^Management, *Optimization, *Method-
ology, Equations, Reservoir storage, Reservoir releases, Mathematical models,
Systems analysis.
Multiple-objective optimization problems arise naturally in resource manage-
ment projects. A chief difficulty with multiple-objective optimization is
that it is no longer clear what one means by an optimal solution. A possible
remedy to this situation is to refine the concept of 'optimal solution' by
introducing the so-called 'noninferior solution set.' Then optimization, in
a multiple-objective context, boils down to determining the set of noninferior
solutions. Determination of the noninferior set is facilitated by relating it,
in a one-to-one manner, to a family of auxiliary scalar optimization problems.
For a certain class of problems the entire noninferior set can be obtained by
solving the auxiliary scalar problem. This procedure is illustrated, con-
sidering the problem of determining the optimum storage capacity of a reservoir
subject to a specified set of release rules. For demonstration purposes,
some simplifications are made. The applicability of this method is presently
restricted to the use of a particular functional form for each vector index
and no constraints. Further research is needed to extend this method to more
general forms of performance indices and to problems in which decision and
state variable constraints are present.
74:06A-004
A CRITICAL REVIEW OF VOLLENWEIDER'S NUTRIENT BUDGET MODEL AND OTHER RELATED
MODELS,
Dillon, ?•J-
Ministry of the Environment, Ontario, Canada, Limnology and Toxcity Branch.
Water Resources Bulletin, Vol. 10, No. 5, p 969-989, October, 1974. 2 tab,
13 ref.
Descriptors: Nutrients, Phosphorus, Eutrophication, Model studies, Water
management.
Early attempts at nutrient budget modeling considered only the case where
there was no loss of the material by sedimentation, i.e. the substance was
assumed to be conservative. Nonstratified and stratified conditions have
both been investigated under these terms. An elegant model, taking into
account loss of a substance by sedimentation as well as flushing was presented
bv Vollenweider in 1969. Although this model has several shortcomings, it is
oarticularly valuable because it can have immediate practical value in terms
of water management policy development. These basic shortcomings in the model
are analyzed and suggestions are made to alter the model to take these factors
into account.
155
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74:06A-005
OPTIMAL ALLOCATION OF WATER QUALITY CONTROLS IN URBANIZING RIVER BASINS,
Walker, W.R., Skogerboe, G.V., and Huntzinger, T.L.
Colorado State University, Ft. Collins, Department of Agricultural Engineering.
Water Resources Bulletin, Vol. 10, No. 5, p 845-859, October, 1974. 8 fig,
16 ref.
Descriptors: *Irrigation water, *Municipal water, *Optimization, Salinity,
Water quality control, Waste water treatment, Water quality standards.
Urbanizing river basins in the west are encountering serious water quality
degradation resulting from the expanded water utilization. In order to avoid
aggravating such conditions, water quality controls need to be implemented.
The important questions are, therefore, where and how to impose such constraints
on the urban and agricultural sectors to achieve the desired level of pollution
control. An application of the model developed to address such questions is
made in the Utah Lake drainage area of Central Utah as a test of the model's
utility. The region is subdivided into five major sub-basins containing both
municipal and agricultural water demands. A submodel of each sub-basin is
developed which optimizes the water quality control strategies by linking the
urban to the agricultural uses and then evaluating the levels of control for
each sector. From these results, a cost-effectiveness function for each sub-
basin is generated. By jointly considering the cost-effectiveness relationship
for each sub-basin, an optimum policy for the entire basin is determined.
74:06A-006
USER-ORIENTED RESEARCH DESIGNS,
Viessman, W., Jr. and Stork, K.E.
Nebraska University, Lincoln, Nebraska Water Resources Research Institute.
Water Resources Bulletin, Vol. 10, No. 3, p 440-446, June, 1974.
Descriptors: 'Research and development, *Research priorities, technology,
*Project planning, *Project purposes.
A user-oriented research plan is presented herein. Its principal components
are: (1) a mechanism for identifying social goals and priorities; (3) a pro-
gram planning technique for designing projects to impact on important research
objectives; (4) a mechanism for coordinating research activities of important
research producers; (5) a structure for encouraging and establishing inter-
disciplinary team efforts when they are required; (6) a well-coordinated
technology transfer plan; and (7) an effective method for promoting and sus-
taining user-researcher cooperation. Both basic and applied research designs
are examined and criteria presented. The implementation of research plans
is also discussed and various factors which play a role in implementation are
outlined including: coordination, goal interpretation and priority setting,
project planning, project review, interdisciplinary considerations and the
user-researcher interface.
74:06A-007
INTERDISCIPLINARY MODELING IN THE ANALYSIS OF THE SALINITY PROBLEMS OF THE
SAFFORD VALLEY,
Muller, A.B.
Arizona University, Tucson, Department of Hydrology and Water Resources.
Water Resources Bulletin, Vol. 10, No. 2, p 245-]55, April, 1974. 6 fig, 9 ref.
Descriptors: Salinity, Saline water, Saline soil, Model studies, Groundwater,
Groundwater recharge, Leaching, Cotton, Economics.
A groundwater quality change of +0.13 millimhos electrical conductivity was
documented between 1940 and 1972 in the Safford Valley. The change is attri-
butable to four principal mechanisms: pumping-encouraged saline artesian
aquifer leakage, natural recharge of the water table aquifer by saline waters,
leaching of agricultural waters into the aquifer and the lateral flow of
groundwater through saline lacustrine beds. A hydrologic study of the area
has shown the first of these mechanisms to be predominant. Salinity modeling
has shown three regions of salinity change, and salinity increase projections
for each are determined. An economic analysis and an' economic model are then
156
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combined with the physical model, yielding information as to when certain
economic conditions are reached with respect to the salinity increase.
74:06A-008
SIMULATION TECHNIQUES FOR WATER PROJECT ANALYSIS,
Holloway, M.L. and Tischler, L.F.
Office of the Governor of Texas, Austin, Office of Information Services.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 211-229, September, 1974. 6 fig, 4 ref, 2
append.
Descriptors: *Simulation analysis, Project planning, Projects, Analytical
techniques, Water supply development.
This paper describes a set of analytical tools designed to measure market and
nonmarket benefits and costs of large water resource systems; selected compo-
nents may be useful for analyzing individual small projects or a general
application to a system of small projects. The focus of the paper is on two
major aspects: (1) A description of techniques developed at the Texas Water
Development Board to measure economic, environmental, and social impacts of
water development projects; and (2) the possible application of these tech-
niques to single small projects or to a system of small projects within a
larger hydrologic, environmental, social, and economic system.
74:06A-009
WATER MANAGEMENT THROUGH IRRIGATION AND DRAINAGE: PROGRESS, PROBLEMS, AND
OPPORTUNITIES,
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR2, p 153-178, June, 1974. 28 ref.
Descriptors: *Water management (applied), Water conservation, Water quality,
Social needs, Social impact.
The purpose of the current effort by the Irrigation and Drainage Research
Committee is not to make yet another recommendation, but rather to encourage
civil engineers to reflect on the problem at hand so that they can draw their
own conclusions and, as appropriate, initiate whatever action they wish.
74:06A-010
MODELING THE HYDROLOGIC EFFECTS RESULTING FROM LAND MODIFICATION,
Fogel, M.M., Duckstein, L., and Kisiel, C.C.
Arizona University, Tucson, Watershed Management Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17,
No. 6» P 1006-1010, November-December, 1974. 3 fig, 1 tab, 22 ref.
Descriptors: *Model studies, Land forming, Hydrology, Watershed management,
Watersheds (basins), Sediments, Sediment yield, Runoff.
The basic objective of this paper is to present a methodology that can predict
the long-term hydrologic effects of land modifications on ungaged watersheds.
as used here, "to predict" is used interchangeably with "to forecast" in the
hydrologic sense. The essential components of the procedure are an event-
based stochastic model of precipitation as input into a deterministic water-
shed model that transforms the inputs into such desired hydrologic variables,
as water yield, peak runoff rate and sediment yield.
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Section XXII
WATER RESOURCES PLANNING
EVALUATION PROCESS (Group 06B)
74t06B-001
APPRAISAL OF IRRIGATION PROJECTS AND RELATED POLICIES AND INVESTMENTS,
Bassoco, L.M., Norton, R.D., and Silos, J.S.
Ministry of the Presidency, Mexico 1, D.F., Mexico
Water Resources Research, Vol. 10, No. 6, p 1071-1079, December 1974.
2 fig, 4 tab, 14 ref.
Descriptors: *Project post evaluation, Project benefits, Linear programming,
Irrigation districts, Irrigation programs, Irrigation.
Seven examples of analysis with linear programming models are used to illustrate
methods of treating interdependence in the appraisal of irrigation projects.
The kinds of interdependence analyzed are (1) between investment projects and
other policy instruments, (2) among different types of investment projects,
and (3) between local and sector-level decision on investment outlays. The
applications discussed refer to irrigation districts in the central plateau and
northwestern littoral of Mexico
158
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Section XXIII
WATER RESOURCES PLANNING
COST ALLOCATION, COST SHARING, PRICING/REPAYMENT (Group 06C)
74:06C-001
DETERMINATION OF THE OPERATION AND MAINTENANCE COSTS OF IRRIGATION PROJECTS,
Rydzewski, J.R.
Southampton University, United Kingdom.
International Commission on Irrigation and Drainage, p 9-13, January 1974.
Append.
Descriptors: Irrigation programs, *Irrigation, *Irrigation operation and
maintenance, Project planning, Projects, Cost analysis.
The paper reviews the problems which stem from an inadequate knowledge of the
nature and extent of recurrent expenses on irrigation projects. It then pre-
sents a methodology for collecting such information from the field and dis-
cusses the reasoning behind it. Finally, it appeals to project administrators
for cooperation with this type of survey, the results of which could have a
beneficial influence on policies affecting project management.
74:06C-002
PRICING IRRIGATION WATER IN IRAN,
Gardner, B.D., Madhi, Y., Partovi, S., Morteza, H., and Mehdi, S.
Utah State University, Logan, Department of Economics.
Water Resources Research, Vol. 10, No. 6, p 1080-1084, December 1974. 2 fig, 1
ref •
Descriptors: Irrigation water, *Water costs, Irrigation, Irrigation districts,
Costs, Cost analysis.
Iran has nationalized water and is faced with the problems of pricing it.
A proposal for pricing irrigation water is presented in which water is managed
by nonprofit water authorities. An irrigation project is divided into zones,
and a single price is proposed for each zone. Operation and maintenance costs
are set as a lower limit on price, and a certain fraction of ability to pay is
get as an upper limit. Zones are ranked by assigned reimbursable costs, and
a system is proposed that would produce water revenues in aggregate equal to
total project reimbursable costs. For those zones where water is priced above
reimbursable cost the price is set at that level where the price minus reimbur-
sable costs, as a percentage of the difference between the upper limit and reim-
bursable cost, is the same for all zones. For those zones where the price is
below reimbursable cost, the recommended price is at the upper limit.
74:06C-003
EFFECT OF NITRATE AND SEDIMENT CONSTRAINTS ON ECONOMICALLY OPTIMAL CROP
PRODUCTION,
Onishi, H. and Swanson, E.R.
Illinois University, Urbana-Champaign, Department of Agricultural Economics.
journal of Environmental Quality, Vol. 3, No. 3, p 234-238, July-September,
1974. 2 fig, 1 tab, 12 ref.
Descriptors: *Watershed management, *Linear programming, Nitrogen, Nitrates,
Conservation, Water quality,- Reservoirs, Erosion.
Crop systems and practices which are economically optimal in a 485.6-ha
(1,200-acre) watershed with a planned recreational reservoir were determined
under conditions of varying constraints on water quality in the reservoir.
Tne technique of linear programming was used. Two requirements related to
sedimentation and three requirements related to nitrate concentration in the
jeachate below the root zone were considered. Thus, six combinations of re-
strictions on the choice of optimal crop systems were imposed. A system
Of charges for all sediment introduced into the reservoir substantially reduced
erosion, irrespective of the limit placed on nitrate concentration in the
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leachate below the root zone. Relaxation of the nitrate limit from 10 nig/liter
to no limit approximately doubled the net income above nonland costs.
160
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Section XXIV
WATER RESOURCES PLANNING
WATER DEMAND (Group 06D)
74x06D-001
MODELING EVAPOTRANSPIRATION AND SOIL MOISTURE,
Saxton, K.E., Johnson, H.P., and Shaw, R.H.
United States Department of Agriculture, Agricultural Research Service,
Columbia, Missouri.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 4,
p 673-677, July-August 1974. 7 fig, 2 tab, 17 ref.
Descriptors: ^Computer models, *Model studies, *Soil moisture, *Evapotrans-
piration, Evaporation, Moisture tension. Moisture content. Corn, Bromegrass,
Hydrologic data, Hydrologic systems. Agriculture.
A digital model was presented which was developed to compute daily actual ET
and soil moisture profiles from inputs of daily potential ET and crop and soil
moisture characteristics. Interception evaporation, soil evaporation, and
plant transpiration were computed separately by several relationships; then
these values were combined to provide daily actual ET estimates. Soil moisture
was redistributed by tension-conductivity relationships. The model was
calibrated and verified by 3 years of data from March through November from
two research watersheds, one in corn and the other in bromegrass. The calcu-
lated actual ET amounts and soil moisture profiles agreed sufficiently with
observed data to be quite useful for hydrologic research and models.
74:060-002
ESTIMATION OF POTENTIAL AND CROP EVAPOTRANSPIRATION,
Hargreaves, G.H.
Utah State University, Logan, Agricultural and Irrigation Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 4,
p 701-704, July-August 1974. 2 tab, 13 ref.
Descriptors: *Evapotranspiration, Evaporation pan, Evaporation, Temperature,
Lysimeter, Agriculture, Scheduling, Climatic data.
This paper analyzes the relative importance of weather elements on potential
evapotranspiration and presents a methodology requiring a minimum of data,
providing for simplicity of computation and presenting a good fit of lysimeter
evapotranspiration measurements for a wide range of climatic conditions. Grass
evapotranspiration or potential evapotranspiration can be approximated from a
variety of equations. The most frequently used elements for computation
include mean air temperature and some form of radiation and/or day length.
Other elements are of relatively minor importance in low elevation arid
locations. For these locations the simple equation (PET • MF x T), requiring
only temperature .measurements produces satisfactory results. In humid areas a
correction for relative humidity is added.
74:060-003
EFFECTS OF AGRICULTURAL ACREAGE REDUCTION ON WATER AVAILABILITY AND SALINITY
TN THE UPPER COLORADO RIVER BASIN,
Howe/ C.W. and Orr, D.V.
Colorado University, Boulder, Department of Economics.
Water Resources Research, Vol. 10, No. 5, p 893-897, October, 1974. 2 fig, 4
tab, 8 ref.
161
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Descriptors: Salinity, Saline water, Colorado River, Colorado River basin,
Cost analysis, Costs, Water demand. Water management, Water quality, Water
supply, Water transfer.
Consideration is given to the costs in terms of regional income likely to be
lost if irrigated acreages were to be reduced in the Upper Main Stem subbasin of
the Colorado River as a means of freeing water for alternative uses and reducing
salt loadings. The cost estimates, known to be biased upward, appear competi-
tive with other water augmentation and salinity reduction programs.
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Section XXV
WATER RESOURCES PLANNING
WATER LAW AND INSTITUTIONS (Group 06E)
74:06E-001
ON THE MEASUREMENT OF ENVIRONMENTAL IMPACTS OF PUBLIC PROJECTS FROM A SOCIO-
LOGICAL PERSPECTIVE,
Singh, R.N. and Wilkinson, K.P.
East Texas State University, Commerce, Department of Sociology and Anthropology.
Water Resources Bulletin, Vol. 10, No. 3, p 415-424, June, 1974. 1 fig,
2 tab, 45 ref.
Descriptors: 'Environment, *Environmental control, Attitudes, Social impact,
Watershed management, Watersheds (Basins)
The major objectives are: (1) to identify the problems involved in measuring
the environmental impacts of public projects from selected perspectives, and
(2) to elaborate a sociological approach used in an empirical investigation in
that respect. The construct of environmental impact of a planned action is
generally operationalized from different perspectives and with different
methodological emphases in the various disciplines. Even the term environment
does not elicit agreement among users as to its exact meaning. Although there
has been a steady increase in the number of studies from a sociological per-
spective concerning environmental problems, there is lack of sociological
counsel in writing environmental impact statements. Overall, we lack socio-
logical methodology and operational procedures for that purpose. In an attempt
to bring some empirical focus to this field, attitudinal measures employed
to discover how residents of a river 'basin perceived negative and positive
environmental impacts of a proposed watershed development project are reviewed.
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Section XXVI
WATER RESOURCES PLANNING
ECOLOGIC IMPACT OF WATER DEVELOPMENT (Group 06G)
74:060-001
PROBLEMS OF SCALE AND DETAIL IN ECOLOGICAL MODELING,
Goodall, D.W.
Utah State University, Logan, Ecology Center.
Journal of Environmental Management, Vol. 2, No. 2, p 149-157, April 1974.
1 ref.
Descriptors: *Model studies, *Ecosystems, Dynamics.
The importance of niche structure in ecosystem dynamics is emphasized. This
implies that an ecosystem model which ignores species differences runs the
risk of neglecting important elements in its dynamics. Unless circumstances
permit direct comparison of a simplified model with the observed behaviour of
a representative range of ecosystems, it is recommended that acceptance of the
simplified model be based on a demonstration that deviations from the behaviour
of an alternative model taking biological diversity fully into account are neg-
ligible for the purposes in question. Spatial heterogeneity, like biological
diversity, may contribute greatly to the dynamics of an ecosystem, and a
simplified model which ignores it should be accepted only if justified either
by an empirical test or by a comparison with a more complex model taking the
heterogeneity into account.
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Section XXVII
WATER RESOURCES
DATA ACQUISITION (Group 07B)
74:076-001
SOIL TEMPERATURE MODELING USING AIR TEMPERATURE AS A DRIVING MECHANISM,
Hasfurther, V.R. and Burman, R.D.
Wyoming University, Laramie, Civil Engineering Department.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 1,
p 78-81, January-February 1974. 6 fig, 1 tab, 1 append.
Descriptors: *Model studies, *Mathematical models, *Soil temperature, *Air
temperature, Temperature, Climatic data. Agriculture.
A mathematical model for predicting soil temperature from air temperature is
developed and should have a great utility because of the availability and
economy of air temperature measurements as compared to soil temperature measure-
ments. The mathematical model will predict daily average soil temperatures
within approximately three degrees farenheit at depths of from 1 inch to 72
inches based on past measurements of average daily air temperature as reported
by a standard weather bureau shelter. Prediction of future soil temperatures
is largely limited by the accurate prediction of air temperatures in advance.
The results of the mathematical modeling technique show that the deviations of
predicted values from the actual values (smoothed values) were usually within
three degrees and more often than not were less than three degrees in error.
74:073-002
REMOTE SENSING TECHNIQUES FOR EVALUATION OF SOIL WATER CONDITIONS,
Schmer, F.A. and Werner, H.D.
South Dakota State University, Brookings, Remote Sensing Institute.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No. 2,
p 310-314, March-April 1974. 6 fig, 3 tab, 8 ref.
Descriptors: *Remote sensing, *Soil moilture, *Grain Sorghum, Films, Filters,
Infrared radiation, Wavelength, Reflectance, Irrigation, Agriculture,
Irrigation practices.
The results of two years of soil water research indicate that remote sensing
did provide a valuable tool in evaluation of soil water condition for the crop
and soils studied. Multispectral data collection and analysis seem to hold the
Xey to the development of the necessary remote sensing techniques for operational
use. Results indicate that early season soil water conditions with little crop
cover of the soil were best monitored with the blue spectral band. As the
season progressed and the crop canopy developed, the sorghum became an indicator
of the available soil water; and the green and red spectral bands became more
useful with red the best of all. Adjusting the film densities from the
reflected imagery to account for variations in incoming radiation provided
improved results in several cases. Thermal infrared radiation may possibly
be the most valuable tool for widespread soil water evaluation since it seems
less affected by differences in vegetative and soil surfaces.
74:073-003
CONTROLLING CENTER PIVOT SPRINKLERS FOR EXPERIMENTAL WATER APPLICATION,
Heerwan, D.F.
United States Department of Agriculture, Agricultural Research Service, Fort
165
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Collins, Colorado.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 7 fig, 7 tab.
Descriptors: *Sprinkler irrigation, *Research equipment, Data collections,
Application equipment, Application methods, Irrigation methods, Irrigation
practices, Irrigation.
Irrigation systems and techniques are often required for various water treat-
ments for water management research. Center pivot irrigation systems were
successfully modified to vary water application depths on droplet size on small
plots or entire sectors. The modifications included controls for varying travel
speed and for automatically starting and stopping individual sprinkler heads.
The modifications made on center pivot systems for three different experiments
were successfully used for applying water treatments. When systems were run at
constant rotation speeds, the coefficient of variability was generally less than
20%. Water treatments applied with center pivot systems required minimal labor
since the systems were designed to automatically affect the desired treatments
as the systems passed over the plot areas.
74:07B-004
SAMPLING AND CALCULATION METHODS FOR DETERMINING QUANTITIES OF NITROGEN AND
PHOSPHORUS IN WATERSHED RUNOFF,
Burwell, R.E., Schuman, G.E., Piest, R.F., Larson, w.E., and Alberts, E.E.
Presented at 1974 Winter Meeting of the American Society of Agricultural
Engineers, December 10-13, 1974. Chicago, Illinois. 2 fig, 5 tab, 10 ref.
Descriptors: Nitrogen,, *Phosphorus, *Agricultural runoff, Sediments, Watersheds
(Basins), Sampling.
The nitrogen and phosphorus content of surface runoff from two watersheds in
southwestern Iowa was analyzed for a 5-year period (1969-1973). Sampling and
calculation procedures were evaluated for quantifying discharges of water-
soluable N03-N, NH4-N, and inorganic P and sediment-associated Kjeldahl N and
NaHC03-extractable P. The arithmetic mean nutrient concentration of samples
collected during major runoff (greater than 10 cfs), multiplied by the quantity
of water or sediment discharged, compared favorably with a standard integration
procedure for determining N and P discharge associated with surface runoff.
74:07B-005
SAMPLING TOOL FOR TAKING UNDISTURBED SOIL CORES,
Robertsom, W.K., Pope, P.E., and Tomlinson, R.T.
Florida University, Gainesville.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 855-857,
September-October, 1974. 4 fig, 2 ref.
Descriptors: Sampling, Soil investigations, Soil properties, Soil surveys,
Soil tests, Leaching.
A tool is described that can be attached to a commercially available soil
sampler that will take undisturbed soil cores 15 cm in diameter and 75 cm long
in corlon tubes. The tubes were sealed at the bottom with a sheet of plastic
in which drainage tubes were inserted. Leaching studies could be made when
tubes containing cores were placed on racks in the greenhouse. Further refine-
ments include suction cups at regular intervals in the side of the column for
nutrient movement studies and porous plates at the top and/or the bottom to
make moisture tension in the profile similar to natural conditions.
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74:078-006
A METHOD FOR MEASURING FIRST-STAGE SOIL WATER EVAPORATION IN THE FIELD,
Arkin, G.F., Ritchie, J.T., and Adams, J.E.
Texas Agricultural Experiment Station.
Soil Science Society of America Proceedings, Vol. 38, No. 6, 951-954,
November-December, 1974. 5 fig, 8 ref.
Descriptors: Evaporation, Soil water, Soil water movement, Automation, Mulching,
Soil investigations, Evapotranspiration, Measurement.
An economical, automated method was developed for measuring soil water evapor-
ation during first-stage drying simultaneously at several locations in a field
to evaluate the effectiveness of mulches and crop canopies in reducing soil
water evaporation. The method also provides a reasonable procedure for separ-
ating soil water evaporation during first-stage drying from transpiration, when
the total evapotranspiration rate is accurately measured. Water flow through
a thin evaporation plate with a known surface area is measured and used as a
direct indicator of the evaporation rate. Flow rates can be recorded manually
or automatically. Field tests of evaporation indicated that the resolution of
the system was equal to that of a precision weighing lysimeter and that the
system gave reasonable accuracy on an hourly basis. Mulch rates of 19000, 4,000
and 10,000 kg/ha-1 reduced daily soil water evaporation measured with this
method by 26, 59, and 78% of the bare soil evaporation. Cumulative, daily soil
water evaporation was reduced by 57 and 71% under plant canopies with 100- and
50-cm row spacings ans similar leaf area indices (3.0 and 2.7, respectively).
74:073-007
AN AUTOMATIC PUMPING SAMPLER FOR EVALUATING THE TRANSPORT OF PESTICIDES IN
SUSPENDED SEDIMENT,
Parr J.F., Willis, G.H., McDowell, L.L., Murphree, C.E., and Smith, S.
journal of Environmental Quality, Vol. 3, No. 3, p 292-294, July-September,
1974. 1 fig, 3 tab, 7 ref.
Descriptors: *Pesticides, *Sampling, Sediment, Suspended solids, Laboratory
tests, Equipment, Water quality, Water pollution.
Laboratory tests were conducted to evaluate the utility of an automatic
pumping sampler for assessing the transport and. concentration of pesticides
in suspended sediment. Pesticide-sediment-water mixtures were formulated
with pesticide-sediment ratios ranging from 1:15,000 to 1:500. After
stirring periods of 10 and 60 min, these formulations were pumped through
the sampler and aliquots collected for pesticide analysis. Recovery of DDT,
trifluralin, toxaphene, and mirex exceeded 90%, based on their concentrations
immediately prior to pumping. Adsorption of pesticides to the various
plastic, rubber, and fiberglass sampler components was minimized by the high
flow velocity and rapid delivery systems ehich ensured a short time of contact
(seconds) between the sample and internal surfaces. These tests indicate
that the sampler is suitable for use in evaluating the transport of relatively
water-insoluble pesticides in suspended sediment.
74:078-008
EVALUATION OF SURFACE WATER RESOURCES FROM MACHINE PROCESSING OF ERTS
MULTISPECTRAL DATA,
Mausel, P.W., Todd, W.J., Baumgardner, M.F., Mitchell, R.A., and Cook, J.P.
Indiana State University, Terre Haute.
journal of Environmental Quality, Vol. 3, No. 4, p 316-321, October-December,
1974. 5 figf 1 tab.
Descriptors: *Water pollution control, *Water pollution, Water management,
Water quality, Water quality control, Environmental control, Monitoring,
Hydrology.
Water resource data that are useful to environmental scientists and planners
frequently are missing, incomplete, or obtained irregularily. A new source
of surface hydrological information can be obtained as often as every 18 days
in some areas through machine-processing of Earth Resources Techonology
Satellite (ERTS) multispectral scanner data. This research focused on the
167
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surface water resources of a large metropolitan area, Marion County
(Indianapolis), Indiana, in order to assess the potential value of ERTS
spectral analysis to water resources problems. The results of the research
indicate that all surface water bodies over 0.5 ha were identified accurately
from ERTS multispectral analysis. Five distinct classes of water were
identified and correlated with parameters which included the i) degree of
water siltiness; ii) depth of water; iii) presence of macro and micro
biotic forms in the water; and iv) presence of various chemical concen-
trations in the water.
168
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Section XXVIII
RESOURCES DATA
EVALUATION, PROCESSING AND PUBLICATION (Group 07C)
74:07C-001
A NOTE ON THE USE OF SPECTRAL ANALYSIS TO DETECT LEADS AND LAGS IN ANNUAL
CYCLES OP WATER QUALITY,
Dowling, J.M.
Colorado University, Boulder, Department of Economics.
Water Resources Research, Vol. 10, No. 2, p 343-344, April 1974. 1 tab, 4
ref.
Descriptors: *Time series analysis, *Water quality. Statistics, Statistical
methods, *Input-output analysis.
Spectral analytic phase statistics can be interpreted as absolute delays in
physical time only if the two series are related as input and output by a
simple delay process. For all other linear input-output systems it is incor-
rect to interpret phase as if there is a simple delay between input and out-
put series. To clarify interpretation of phase leads and lags, an explicit
model should be constructed in the time domain. Without such clarification,
ambiguities will be present in the interpretation of phase statistics.
74:07C-002
PARAMETER IDENTIFICATION IN FIELD PROBLEMS,
Simundich, T.M.
California University, Santa Barbara, Department of Mechanical Engineering.
Water Resources Research,' Vol. 10, No. 1, p 73-79, February 1974. 1 fig, 6
tab, 23 ref.
Descriptors: *Data collections, *Hydrologic data, *Systems analysis, *Para-
metric hydrology, Mathematical models, Optimization.
In water resources field problems, unknown physical parameters in the govern-
ing partial differential equations must be determined before relevant numerical
results can be obtained. The identification of these parameters is formulated
as a minimization problem in which the function to be minimized is a least
squares comparison between the model equation and the systems responses (the
field data). The minimization technique utilized is the Fletcher-Powell method.
Three typical water resources field problems are used as examples to demonstrate
the -technique.
74:07C-003
HULTIVARIATE TECHNIQUES FOR WATER QUALITY ANALYSIS,
jlahlock, J.L.
Mississippi State University, State College, Department of Civil Engineering.
journal of the Environmental Engineering Division, American Society of civil
Engineers, Vol. 100, No. EE5, Proceedings paper No. 10840, p 1119-1132, October
1974. 9 tab, 5 equ, 8 ref.
Descriptors: *Environmental engineering, *Water quality control, *Statistical
methods, Regression analysis, Estimating, Data collections, Methodology, in-
formation retrieval, Systems analysis. Equations.
The application of multivariate statistical techniques to analysis of water
169
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quality data is demonstrated. Study results indicate that a simultaneous,
multiple regression technique may be used for supplying missing observations
and that at any particular level the entire data matrix may be considered,
thus reducing the computational effort. Multivariate technique applications
herein center on either extracting information from the data or testing hy-
potheses which may arise concerning the data. The techniques considered in-
clude principal components, canonical correlation, partial correlation, multi-
variate analysis of variance (MANOVA), and discriminant analysis. Examples
are presented demonstrating the application of these methods.
170
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Section XXIX •
ENGINEERING WORKS
STRUCTURES (Group 08A)
74:08A-001
DETERIORATION OF CONCRETE DITCH LINERS IN SALINE-ALKALI SOIL,
Grass, L.B. and Koluvek, P.
Imperial Valley Conservation Research Center, Brawley, California, Agricultural
Research Service.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 477-484, December, 1974. 3 fig, 2 tab, 10 ref.
Descriptors: Concrete construction, Concrete structures, Concrete-lined canals,
Irrigation canals, Irrigation engineering.
Deterioration of portland cement concrete ditch liners in Imperial Valley,
California, is first indicated by a softening, cracking, and eroding of the
liner, beginning at the top and progressing downward. Deterioration is most
severe on the north slope of east-west oriented ditches. Both chemical and
physical reactions are responsible for the gradual softening of the concrete
ditch liners. Physical forces cause weakened liners to crack, which accelerates
the chemical attack by exposing new surfaces. Since Ca and other elements
are more soluble in deteriorated concrete at the upper portions of the liner
than in the lower portions, chemical deterioration seems the predominant form
of deterioration. External physical forces, e.g., cracking due to differences
in temperature above and below the water levels, accelerate the chemical corro-
sion.
74:08A-002
DESIGNING TRICKLE IRRIGATION LATERALS FOR UNIFORMITY,
Howell, T.A. and Hiler, E.A.
Texas A&M University, College Station, Department of Agricultural Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 443-454, December, 1974. 9 fig, 11 ref,
2 append.
Descriptors: Irrigation design, Irrigation engineering, Irrigation systems,
Hydraulic design, Uniform flow,
Design equations are presented that allow the length of a trickle irrigation
lateral to be designed to meet specific uniformity criteria. The emitter
flow function is utilized to determine the allowable pressure loss to meet
the uniformity standards. The emitter flow variation of the lateral (increase
or decrease as compared to the -design flow rate) is a function of the uniformity
coefficient. Thus, by knowing the emitter flow function, elevation change,
and design uniformity, the allowable pipe friction loss can be computed. Then
taking the pipe size, pipe roughness coefficient (Hazen-Williams), reduction
coefficient for dividing flow, average emitter flow rate, allowable pipe
friction loss determined previously, and either the number of emitters per
lateral, N, or the average emitter spacing, S, into account the lateral length,
L, can be determined. The solution for a given value of uniformity is a log-
linear (log N versus log L or log S versue log L) with a slope that depends
only on the flow rate exponent in the pipe friction loss equations for level
laterals.
74-.08A-003
ECONOMIC PIPE SIZING IN PUMPED IRRIGATION SYSTEMS,
perold, R.P.
Stellenbosch University, Republic of South Africa, Department of Agricultural
Engineering.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR4, p 425-441, December, 1974. 7 fig, 1 tab, 11 ref,
2 append.
171
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Descriptors: Irrigation design, Piping systems, Economics, Irrigation engineer-
ing.
The method whereby the most economical pipe sizes in a pumped system is found
by determining the flow rates at which pipe sizes should be changed from one
size to the next, according to the time pumped per year, is developed for
general application. Use of the method in the design of branched flow system
is examined for both fixed head and variable head pumping plants. The method,
as illustrated by an example, is found to be convenient and gives the best solu-
tion fairly rapidly.
74:08A-004
MIXING IN SPRINKLER IRRIGATION SYSTEMS,
Hermann, G.J., McMaster, G.M. and Fitzsimmons, D.W.
CH2M/Hill, Redding, California, Agricultural Engineering.
Transactions of the ASAE, Vol. 17, No. 6, p 1020-1024 ,& 1028, November-December,
1974. 6 fig, 9 ref.
Descriptors: *Sprinkler irrigation, Irrigation practices, Irrigation, Mixing,
Irrigation water, Fertilization, Fertilizers.
A study was conducted at Aberdeen, Idaho, to determine the amount of mixing
between two fluids traveling in a branching flow lateral under the field con-
ditions found in a sprinkler irrigation system. The objective of the study
was to develop methods to predict the effects of state of flow, of couplers
and of branching flow on mixing and dilution of chemicals injected into
operating sprinkler irrigation laterals. The resulting basic understanding
of branching flowmixing could be used to manage chemical applications through
sprinkler systems for best placement and effectiveness. Using irrigation
systems to apply chemicals will reduce the usage of conventional application
equipment and result in labor and energy savings as well as a reduction of
soil compaction and crop damage.
74:08A-005
PIPE SIZE SELECTION FOR COMMUNITY IRRIGATION SYSTEMS,
Chu, S.T.
South Dakota State University, Brookings, Department of Agricultural Engineer-
ing.
Transactions of the ASAE, Vol. 17, No. 6, p 1029-1032 & 1037, November-
December, 1974. 3 fig, 3 tab, 13 ref.
Descriptors: Irrigation design, Irrigation engineering, Irrigation, Pipelines,
Pipes, Piping systems, Economics, Community development.
An analytical result and procedures to select optimal pipe sizes for the water
delivery pipe network of community irrigation systems were developed. The
application of the presented method to the Shamrock Irrigation Project showed
that the result is an acceptable approximation of the result obtained by linear
programming. The time required to use the presented method for selecting
pipe sizes is less than the time needed to prepare computer cards for the
linear programming.
74:08A-006
ANALYSIS OF CANAL SEEPAGE TO INTERCEPTOR DRAIN,
Sharma, H.D. and Chawla, A.S.
U.P. Irrigation Research Institute, Roorkee, India.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 351-369, September, 1974. 11 fig, 5 ref, 2
append.
Descriptors: *Canal seepage, Seepage, Seepage control, Drainage effects,
Drainage practices.
An analytical solution is obtained with the help of conformal mapping for the
problem of steady seepage from a canal into an interceptor drain and to the
172
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main drainage lain in homogeneous and isotropic medium extending to infinite
depth. Equations have been given to determine the seepage discharge into the
drain and the coordinates of the phreatic surface. The solutions of the equa-
tions have been presented in the form of dimensionless curves to facilitate
computations. The analysis indicates that discharge to the interceptor drain
increases with an increase in the bed width of the channel and diameter of
interceptor drain, whereas it decreases with an increase in distance between
the canal and the interceptor drain. As the drain is brought closer to the
canal, the rate of increase of seepage into the drain increases. The effect
of the drain diameter in intercepting seepage discharge is more pronounced at
a deeper setting of the drain.
74:08A-007
BASIC PRINCIPLES OF PULSE IRRIGATION,
Karmeli, D. and Peri, G.
Technion Haifa Israel, Faculty of Agricultural Engineering.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 309-319, September, 1974. 2 fig, 3 tab,
append.
(See 74:03F-153)
74:08A-008
CENTER PIVOT DESIGN CAPACITIES IN EASTERN COLORADO,
Heermann, D.F., Shull, H.H. and Mickelson, R.H.
United States Department of Agriculture, Fort Collins, Colorado.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR2, p 127-141, June, 1974. 9 fig, 3 tab, 15 ref.
Descriptors: *Sprinkler irrigation, Irrigation design, Irrigation engineering,
Irrigation practices, Irrigation systems, Flow rates, Design flow.
Design system capacities were developed for center pivot sprinklers irrigating
corn in the Central Great Plains by simulating irrigations for 60 years of
climatic data collected at Akron, Colorado. The system design provides three
probability levels of net irrigation requirements versus optimum soil water
depletion as affected by soils with various water holding capacities. The
design system capacities developed from the simulation model allow for the
depletion of available soil water. An emperical procedure for determining
the net system capacity from ET (net) as affected by allowable depletion level
is presented.
74:08A-009
A LABORATORY TEST OF SOME DRAIN TUBE FILTER MATERIALS,
McKyes, E. and Broughton, R.S.
Macdonald Campus of McGill University, Ste Anne de Bellvue 800, Quebec.
journal of the Canadian Society of Agricultural Engineering, Vol. 16, No.
2, p 60-62, December 1974. 5 fig, 6 ref.
Descriptors: *Drainage, *Drainage effects, *Drainage engineering, *Drainage
practices, Filtration, Drains, Materials testing.
Drainage systems frequently fail in fine sandy soils because of particles
entering drain tiles in sufficient quantity to block the drains. Attempts have
been made to employ filters outside tiles to allow only soil-free water to
enter the system. Filtering materials have included straw, fiberglass sheet,
polyester fiber sheet, nylon fiber sheet, coconut fibers, and others. Some
field experience has shown that the flow of water can decrease over the years
through filters, especially in iron-rich soils. However, no laboratory tests
have been performed to note the effect of months of water-flow through filters,
and the relative amounts of sand entry through filters over a long period.
The purpose of this study was to test some commercially available or promising
filters for corrugated plastic drain tubes and to access their effect on water
and soil entry into tubes over approximately 2 mo of continuous operation.
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74:08A-010
SCREEN THEORY FOR WELLS AND SOIL DRAINPIPES,
Sami Selim, M. and Kirkham, D.
Iowa State University, Ames, Department of Agronomy.
Water Resources Research, Vol. 10, No. 5, p 1019, 1030, October, 1974. 19
fig, 3 tab, 19 ref.
Descriptors: *Well screen, *Wells, Theoretical analysis, Hydraulic design.
Hydraulic equipment, Hydraulic properties, Irrigation wells.
A theoretical solution is given for steady flow in a confined aquifer to a well
tube having equally distributed screens. It is shown, quantitatively, by use
of Darcy's law and Laplace's equation, that more flow results if a given total
length of well screen is utilized in a number of sections over the full length
of the well tube than if the given length of well screen is all used at the
bottom of the tube. For a pumped well of 0.25-ft radius, 200-ft radius of
influence, 50-ft thickness of aquifer, and 25-ft length of screen the use of
the screen in five 5-ft long sections equally distributed over the well tube
results in 25% more well flow than if the 25-ft length of screen is all in
one piece at the lower 25 ft of the aquifer. The results are presented in
tables and graphs having dimensionless parameters so that the flow for a partic-
ular flow system may be found in any units. Mathematically, the problem
is of the mixed boundary value type.
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Section XXX
ENGINEERING WORKS
HYDRAULICS (Group 088)
74,088-001
HYDRODYNAMICS OF SURFACE IRRIGATION-ADVANCE PHASE,
Sakkas, J.G. and Strelkoff, T.
California University, Davis, Department of Water Science and Civil Engineering.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IRl, Paper 10422, p 31-48, March 1974, 8 fig, 19
ref, append.
Descriptors: *Seepage, *Open channel flow, *Furrow irrigation, *Surface
irrigation, Numerical analysis, Infiltration, Hydrodynamics.
The Saint-Venant equations governing gradually varied, unsteady flow in an
open channel with seepage may be put into characteristic form and solved
numerically in finite steps along the irregular network formed by the charac-
teristic lines using a simple predictor-corrector scheme. Infiltration into
the soil is assumed to depend solely upon contact time between water and soil.
In regions of substantial curvature of the characteristic lines, step size is
reduced to preserve accuracy. Near the very front of the advancing stream,
where the forward and backward characteristics curve extremely sharply and
merge with their envelope, the wave-front trajectory, the numerical approxi-
mations to the characteristic equations break down and are replaced by the
assumption that water velocity is independent of the distance coordinate and
equals front-propagation speed.
74:088-002
DISCHARGE AND TRAVEL TIME FOR GROUND-WATER CONDUITS,
Butler, S.S. and Gundlach, D.L.
University of Southern California, Los Angeles, Department of Civil Engineering.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IRl, Paper 10393, p 17-29, March 1974. 11 fig, 1
tab, 4 ref, append.
Descriptors: *Groundwater movement, ^Discharge (Water), *Travel time, Mathe-
matical models, Aquifers, Water yield. Permeability, Porous media, Irrigation
water, Percolation, *Conduits.
A system of mathematical and graphical procedures gives solution for the
steady-flow discharge and travel time for nonuniform confined groundwater
conduits in which any or all of the following characteristics vary from point
to point: permeability, porosity, and cross-sectional area. The methods
based on the Darcy equation and the equation of continuity. Modified pro-
cedures give relatively simple solutions with some loss in accuracy.
74:088-003
PROCEEDINGS OF THE SECOND INTERNATIONAL DRIP IRRIGATION CONGRESS,
Second International Drip Irrigation Congress',
California University and United States Department of Agriculture, Agriculture
Research Service.
Second International Drip Irrigation Congress, July 7-14, 1974, San Diego,
California.
(See 74:03F-006)
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74:08B-004
LOW PRESSURE JET CLEANING OF PLASTIC DRAINS IN SANDY SOIL,
Ford, H.W.
Florida University, Lake Alfred, Agricultural Research and Education Center.
Transactions of the American Society of Agricultural Engineers, Vol. 17, No.
5, p 895-897, September-October, 1974. 3 fig, 1 tab, 6 ref.
Descriptors: *Jets, *Drainage practices, *Subsurface drains, Cleaning, Drains,
Drainage systems. Sludge, Florida, Agriculture
This paper describes a low pressure jetting method for removing sludges from
plastic drains and from the surrounding thin gravel envelope utilized in
Florida sandy soils. There was no sand infiltration using gravel envelopes
0.75 to 1.50 in thick with corrugated plastic polyethyleve pipe employed in
drain installations. A low pressure jet cleaning system can function in 4-
to 5-in. plastic drains up to 550 ft. in length where ochre and FeS are the
primary deposits to be removed. Cleaning of the gravel envelope can be
accomplished presumably by the surging action of jetting pressure. Jetting
should be performed at a slow entry rate and with a hydraulic head above the
drain. In sandy areas where sludges are a problem, jetting should be performed
within 2 weeks after initial drain flow.
74:088-005
NUMERICAL ANALYSIS OF PUMPING FROM CONFINED-UNCONFINED AQUIFERS,
Rushton, K.R. and Turner, A.
Birmingham University, England, Department of Civil Engineering.
Water Resources Bulletin, Vol. 10, No. 6, p 1255-1269, December, 1974. 8 fig,
1 tab, 8 ref.
Descriptors: *Pumping, Aquifers, Wells, Groundwater movement, Numerical
analysis, Drawdown, Groundwater.
A numerical method is presented for the analysis of a pumped well in a homo-
geneous aquifer with allowance made for the decrease in saturated depth,
vertical components of flow, the possibility of regions of the aquifer changing
between the confined and unconfined states and the effect of different outer
boundaries. The method is based on a discrete space, backward difference
time, approximation. A particular example considered in detail concerns
heavy pumping from one of a regular array of wells in an unconfined aquifer
until the drawdown in the well reaches a critical value. Non-dimensional
curves are presented relating the time and volume dewatered to the quantity
discharged from the well. A further example investigates the effect of an
initial confining pressure on the aquifer behaviour.
74:088-006
ECONOMIC PIPE SIZING FOR GRAVITY SPRINKLER SYSTEMS,
Perold, R.P.
Stellenbosch University, Republic of South Africa, Agricultural Engineering
Department.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR2, p 107-116, June, 1974. 3 fig, 4 tab, 2 ref,
2 append.
Descriptors: *Pipelines, *Pipes, Economics, Sprinkler irrigation, Irrigation,
Irrigation design, Irrigation engineering, Hydraulic design, Hydraulics.
A method is described for finding the most economical pipe sizes in gravity
systems by comparing financial gains and losses resulting when pairs of changes
in pipe size are made in various portions of a system in such a way that the
additional pressure losses and gains balance. The influence of branches is
treated and application to time-variable branched flow is examined. As shown
in examples, the method rapidly gives the most economical solution.
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Section XXXI
ENGINEERING WORKS
HYDRAULIC MACHINERY (Group 08C)
74:08C-001
TRICKLE IRRIGATION IN MICHIGAN ORCHARDS: CONTROLLING RATE OF FLOW WITH FLOW
REGULATING VALVES AND MICROTUBES,
Kenworthy, A.L. and Kesner, C.
Michigan State University, East Lansing, Michigan.
Proceedings of the Second International Drip Irrigation Congress, pp.
275-280, July 1974. 3 fig, 2 tab, 2 ref.
Descriptors: Flow rates, Michigan, Irrigation systems, Orchards, Irrigation,
Agriculture.
An appropriate combination of flow regulating valves and microtubes of differ-
ent inside diameter has been found ideal for studying rates of flow in trickle
irrigation. The flow regulating valve is installed in a row lateral. Capacity
of the valve is selected to provide the amount of water desired for the row.
To distribute the water and counter elevation changes, microtubes of different
inside diameters are used and thus avoid excessive microtube lengths. Selec-
tion of an appropriate microtube ID in accordance to flow rate will permit a
uniform value to adjust microtube length according to elevation change. Data
on uniformity of water distribution is presented.
74:08C-002
DESIGN CHARTS FOR DRIP IRRIGATION SYSTEMS,
Wu, I-P. and Gitlin, H.M.
Hawaii University, Honolulu, Hawaii.
Proceedings of the Second International Drip Irrigation Congress, pp. 305-310,
July 1974. 3 fig, 4 ref.
Descriptors: *Irrigation design, *Design flow, *Design criteria, *Hydraulic
design, Hydraulics, Irrigation systems, Irrigation, Agriculture, Design.
A simple design procedure has been developed for drip irrigation systems in-
stalled on either uniform or non-uniform slopes. The charts presented can be
used to design a system with an allowable discharge (emitter) variation up to
20%. A dimensionless energy gradient curve has been developed theoretically
for drip irrigation lines, submain and lateral, and was checked by laboratory
and field experiments. It was found that a typical dimensionless energy gradi-
ent curve which was developed by using turbulent flow in smooth pipe can be
used for flow conditions having 20% discharge (emitter) variation and percentage
of laminar flow up to 30%. The dimensionless energy gradient curve combined
with different slope conditions will show the pressure variation along the
drip irrigation line. Design charts have been developed for both single
tubing and twin-chamber drip irrigation systems. Examples are presented
showing the design procedure.
74:08C-003
HIGH-PRESSURE WATER JET CLEANING OF SUBSURFACE DRAINS,
Grass, L.B. and Willardson, L.S.
United States Department of Agriculture, Agricultural Research Service,
Brawley, California, Imperial Valley Conservation Research Center, Western
Region.
Transactions of the American Society of Agricultural Engineers, Vol. 17, NO. 5,
p 886-888 and 891, September-October 1974. 7 fig, 8 ref.
Descriptors: *Jets, *Drainage practices, *Hydraulic equipment, *Hydraulic
machinery, Cleaning, Tile drains. High pressure. Drains, Drainage systems,
Hydraulics, Subsurface drains. Agriculture.
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High pressure jetting equipment utilized the macerating action of high-velocity
water jets and vigorous water turbulence to clean roots, silt, and chemical
deposits from subsurface drains. Water exiting from the rear jets propels the
nozzle and hose up the drain. Two types of nozzles are most commonly used in
Imperial Valley: (a) the cleaning nozzle used mainly for removing silt and
mineral deposits requiring a pump pressure of 1250 psi and a nozzle pressure of
700 psi; and (b) the penetrator nozzle, used mainly for removing root plugs
and the larger, more difficult accumulations of silt requiring pump pressure of
1000 psi and a nozzle pressure of 500 psi. A dewatering pump is used to remove
the dislodged material arriving at the tile opening. The jet cleaning operation
also can locate breaks in subsurface drain lines so that they can be repaired.
178
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Section XXXII
ENGINEERING WORKS
SOIL MECHANICS (Group 08D)
74:08D-001
SEEPAGE RATES AND THE HORIZONTAL PLOW APPROXIMATION,
youngs, E.G.
Agricultural Research Council, Cambridge, England, Unit of Soil Physics.
Water Resources Research, Vol. 10, No. 4, p 874-876, August 1974. 5 fig, 6
ref, 1 append.
Descriptors: *Seepage, *Dams, *Groundwater movement, *Porous media. Con-
ductivity, Dupuit-Forchheimer theory, Hydraulics.
Attention was drawn to a particular case of seepage through a porous body in
which the flow is everywhere horizontal and hence easily calculated. In an
appendix the seepage through a dam core with a cross section in the shape of
an isosceles triangle was shown to be estimated with sufficient accuracy for
practical purposes by the horizontal flow approximation.
74:080-002
POWDERED METAL PLATES FOR CONSTRUCTING UNSATURATED FLOW CELLS,
Bianchi, W.C.
United States Department of Agriculture, Agricultural Research Service, Fresno,
California, Water Management Research.
Soil Science Society of America Proceedings, Vol. 38, NO. 4, p 683-684, July-
August, 1974. 3 fig, 1 tab, 4 ref.
(See 74:02G-021)
74:080-003
SMALL TENSIOMETERS FOR FIELD AND LABORATORY STUDIES,
Rogers, J.S. '
United States Department of Agriculture, Agricultural Research Service, Gaines-
ville/ Florida.
Soil Science Society of America Proceedings, Vol. 38, No. 4, p 690-691, July-
August, 1974. 1 fig.
(See 74:020-022)
74:080-004
DETERMINING EFFECTIVE SOIL WATER DIFFISIVITIES FROM ONE-STEP OUTFLOW
EXPERIMENTS,
Gupta, S.C., Farrell, D.A., and Larson, W.E.
Minnesota University, St. Paul.
Soil Science Society of America Proceedings, Vol. 38, No. 5, p 710-716.,
September-October, 1974. 7 fig, 15 ref, append.
(See 74:020-023)
74:080-005
EFFECT OF BACKFILL ON DRAIN FLOW IN LAYERED SOILS,
Hwang/ R.B., Luthin, J.N. and Taylor, G.S.
California University, Davis.
journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 100, No. IR3, p 267-276, September, 1974. 4 fig, 1 tab, 10
ref.
Descriptors: *Drainage practices, Drainage engineering, Drains, Soil profiles,
Soil properties, Hydraulic conductivity, Backfill, Compaction, Compacted soils.
179
-------
The purpose of the work presented herein is to shed some light on the transient
flow towards drains in layered soils with the ultimate goal of improving the
techniques of drainage design. The combination of layers occurring in the field
soils is very great but experience shows that many soils can be treated
as two-layered soils from a standpoint of drainage design. Trial-and-error
methods in the field may well be the best way to treat some of the more compli-
cated soil layering problems. However, for soils that can be approximated by
a two-layer model the results presented herein will improve our understanding
of the flow towards drains and the effect of the backfill material on such
flow.
74:080-006
EFFECTS OF WATER MANAGEMENT AND SOIL AGGREGATION ON THE GROWTH AND NUTRIENT
UPTAKE OF RICE,
Obermueller, A.J. and Mikkelsen, D.S.
California University, Davis, Department of Agronomy and Range Science.
Agronomy Journal, Vol. 66, No. 5, p 627-632, September-October, 1974. 5 tab,
20 ref.
(See 74:03F-162)
180
-------
Section XXXIII
AUTHOR INDEX
Abtol, I. p.
74:03F-168
Adams , F .
74:03F-123
Adams , J . E .
74:03F-141
74:073-006
Adriano, D. C.
74:02G-041
Ahuja, L. R.
74:02G-011
74:02G-024
74:04B-014
Alberts, E. E.
74:07B-004
Aleti, A.
74:05B-035
Aljibury, F. K.
74:03F-007
74:03F-008
74:03F-009
74:03F-051
74:03F-080
Allen, S. E.
74:03F-125
74:03F-134
Aiy, A. I. M.
74:03F-184
Allred, E. R.
74:03F-005
74:03F-034
Amar, A. C.
74:048-007
Andersen, J. R.
74:058-028
74:05B-043
Anderson, D. M.
74:020-001
Andrew, R. H.
74:03F-165
Ardakani, M. S.
74:058-017
Arkin, G. F.
74:03F-141
74:078-006
74:03F-052
Avinimelech, Y.
74:02G-042
74:048-019
Babu, D. K.
74:02G-003
Bailey G. W.
74:058-006
Baker, F. G.
74:02G-032
Balasubramanian, V.
74:02G-043
Ball, J. W.
74:05A-002
Balogh, J.
74:020-004
Banin, A.
74:02C-001
Baouma, J.
74:02G-046
Barber, S. A.
74:03F-183
Barfield, 8. J.
74:05A-003
Bartley, T. R.
74:05C-005
Bartholomew, W. V.
74:03F-142
Bassoco, L. M.
74:068-001
Baumgardner, M. F.
74:02J-009
74:078-008
Baur, J. R.
74-.05B-045
Bazzaz, F. A.
74:058-044
Bear, J.
74:02F-018
Beckers, C. V.
74:05A-001
Belcher, C. R.
74:021-002
Benecke, P.
74:02G-031
181
Benecke, P.
(cont.)
74:03F-139
Bennett, A. C.
74:03F-123
Bennett, J. P.
74:02J-003
Bennett, R. S.
74:05G-001
74:05G-003
Benz, L. C.
74:03F-160
Bernal, C. T.
74:030003
74:03F-133
Bernstein, L.
74:03F-152
74:03F-156
Berry, F. A.
74:02K-001
Besemer, s.
74:03F-029
Bester, D. H.
74:03F-010
Bhatnagar, V. K.
74:030005
Bezdicek, D. F.
74:03F-122
Bhumbia, D. R.
74:03F-168
Bianchi, W. C.
74:020-021
74:04B-021
74:080-002
Bielorai, H.
74:058-053
Biggar, J. W.
74:02G-007
74:03F-132
74:058-019
74:058-020
74:058-021
Bilbro, J. D.
74:03F-159
Bingham, F. T.
74:030003
74:03F-133
-------
Black, J. D. F.
74:03F-011
74:03F-012
74:03F-059
Blackwell, J.
74:03F-044
Blad, B. L.
74:03F-169
Blake/ G. R.
74:03F-167
74:05B-024
Bleak, A. T.
74:03F-166
Bloomsburg, G. L.
74:02G-018
Bohn, G. W.
74:03F-088
Bohn, H. L.
74:056-025
Bolt, G. H.
74:02G-030
74:03F-138
Bondurant, J. A.
74:02J-010
74:058-049
BOOS, R. P.
74:03F-099
Bordovsky, D. G.
74:03F-171
Boruvka, L.
74:04A-010
Bouma, J.
74:02G-032
Bovey, R. W.
74:058-045
Branson, R. L.
74:03F-013
74:03F-030
74:03F-038
74:03F-039
74:03F-055
Brady, R. A.
74:03F-158
Bravdo, B.
74:03F-052
Bredehoeft, J. D.
74:058-013
Brehm, R. D,
74:03F-108
Breslaw, J. A.
74:056-041
Bresler, E.
74.-02G-006
74:020-039
Broadbent, F. E.
74:03F-121
74:05B-018
Brock, R. R.
74:048-007
Brosz, D. D.
74:03F-120
Broughton, R. S.
74:08A-009
Brown, M. J.
74:02J-010
74:05B-049
Brutsaert, W.
74:02G-040
Bubenzer, G. D.
74:050-034
Bucks, D. A.
74.-03F-014
74:03F-015
74:03F-154
Buddemeier, R. W.
74:048-004
Burau, R. G.
74:020-033
Burman, R. D.
74:078-001
Burnett, E.
74:020-049
74:058-045
Burwell, R. E.
74:058-014
74:058-052
74:078-004
Butler, S. S.
74:08B-002
Cahill, T. H.
74:040-005
Campbell, G. S.
74:030-005
Campbell, M. D.
7.4:030005
Carter, .D. L.
74:02J-010
74:058-049 •
Cartwright, K.
74:02F-006
Case, C. M.
74:02F-020
Cassel, D. K.
74:058-022
Chamberlain, S.G.
74:05A-001
Chancellor, W. J.
74:03F-114
Chaudhary, T. N.
74:030-005
Chawla, A. S.
74:03F-151
74:08A-006
Chen, R. L.
74:04A-007
Chiu, A. y.
74:058-035
Choresh, Y.
74:03F-094
Chu, S. T.
74:08A-005
Church, M. R.
74:05C-003
Clark, M.
74:048-020
Clark, R. A.
74:03F-156
Cockroft, B.
74:03F-092
Colbeck, S. C.
74:020-002
Cole, P. J.
74:03F-016
Commoner, B.
74:058-037
Converse, J. C.
74:05B-034
Cook, J. P.
74:078-008
Corwin, N.
74:050-002
Cottor, D. J.
74:03F-027
182
-------
Crutchfield, J. D.
74:053-009
Cummings, R. G.
74:04B-006
Dalai, R. C.
74:03F-140
Dan, C.
74:03F-017
74:03F-018
Daniel, T. C.
74:02G-046
Daniels, R. B.
74:05B-054
Danielson, J.
74:04B-002
Dargan, K. S.
74:03F-168
Dass, P.
74:02G-014
Davidson, J. M.
74:04B-013
Davis, K. R.
74:03F-021
Davis, R. J.
74:058-007
Davis, S.
74:03F-013
74:03F-019
74:03F-020
74-.03F-038
74:03F-039
74:03F-055
74:048-010
Dawdy, D. R.
74:02A-002
Day / J • c •
74:058-040
DeBock,
74:020-013
nelleur, J. W.
74:06A-001
Denny/ J- L-
74:02E-004
neshmukh, M. T.
v 74:03F-022
74:03F-023
nickens, W. L.
v 74:03F-003
Dicker, D.
74:02G-003
Dillon, P.J.
74:06A-004
Dirksen, C.
74:020-010
74:020-035
74:03F-116
Doering, E. J.
74:03F-160
Donovan, T. J.
74:02G-045
Dornbush, J. N.
74:058-028
74:058-043
Doss, 8. D.
74:03F-145
74:03F-146
74:03F-170
Dougherty, C. T.
74:03F-173
74:03F-174
74:03F-175
Dowling, J. M.
74:070-001
Drake, J. J.
74:02E-003
Duffy, J.
74:058-037
Duckstein, L.
74:06A-010
Duke, H. R.
74:03F-095
Dusek, D. A.
74:03F-098
Ehlig, C. F.
74:03F-096
Eklund, C. D.
74:058-046
Ellis, D.F.
74:058-010
EL-Swaify, S. A.
74:03F-131
Emerson, F. H.
74:03F-058
Endelman, R. J.
74:058-050
Enfield, C. G.
74:03F-124
Engelbert, C. D.
74:02J-008
Engleman, R. L.
74:02J-008
Environmental En-
gineering Divi-
sion of ASCE, Ag-
ricultural Waste
Management Commit-
tee
74:04A-001
74:050-004
Epstein, E.
74:058-023
Erie, L. J.
74:03F-014
74:03F-015
74:03F-154
Ertsgaard, B. L.
74:03F-096
Evans, S. D.
74:058-024
Farquhar, G. J.
74:058-016
Farrell, D. A.
74:020-023
74:02G-029
74:080-004
Farrell, M. D.
74:03F-024
Farvolden, R. N.
74:02F-004
Fausey, N. R.
74:03F-004
Feddes, R. A.
74:020-039
Fenske, P. R.
74:02F-020
Fischbach, P. E.
74:03F-101
74:03F-103
74:03F-109
Fischer, B.
74:03F-051
Fitzsimmons, D. W.
74:020-018
74:03F-150
74:08A-004
Fogel, M. M.
74:06A-010
183
-------
Follett, R. F.
74:03F-160
Fonken, D. W.
74:03F-103
74:03F-109
Ford, D. C.
74:02E-003
Ford, H. W.
74:08B-004
Foster, G. R.
74:02J-006
Framji, K. K.
74:02G-038
Francois, L. E.
74:03F-156
Frank, K. D.
74:03F-110
Fraser, G. 0.
74:03F-026
Freeburg, R. S.
74:03F-027
Freeze, R. A.
74:02F-012
French, 0. F.
74:03F-014
74:03F-015
74:03F-154
Freyer, H. D.
74:03F-184
Frith, G. J. T.
74:03F-028
Furuta, T.
74:03F-028
74:03F-030
Gaffney, F. B.
74:021-002
Gahler, A. R.
74:050-001
Gangstad, E. 0.
74:050005
Gardner, B. D.
74:060-002
Gardner, B. R.
74:03F-073
Gardner, H. R.
74:02D-002
Garzoli, K. V.
74:03F-044
Cast, R. G.
74:02G-044
Gates, C. T.
74:03F-177
Gburek, W. J.
74:053-015
Gelhar, L. W.
74:02F-003
Gentzsch, E. P.
74:020-050
Geraldson, C. M.
74:03F-031
Gerard, C. J.
74:02G-008
74:03F-032
Gerdts, M.
74:03F-007
74:03F-008
Gilaad, Y.
74:03F-033
Gilley, J. R.
74:03F-005
74:03F-034
Gillham, R. W.
74:02F-004
Gilliam, J. W.
74:058-046
74:058-054
Gilmour, J. T.
74:058-050
Gitlin, H. M.
74.-03F-102
74:080-002
Goldberg, D.
74:03F-064
Goldberg, S. D.
74:03F-035
74:03F-083
Goldman, J. C.
74:050-004
74:050-002
Goltz, S. M.
74:03F-158
Goodall, D. W.
74:060-001
Goss, 0. W.
74:030-004
74:03F-149
Gotoh, S.
74:058-027
Goubran, R. G.
74:03F-081
Grass, L. B.
74:08A-001
Grass, L. S.
74:080-003
Gray, W. G.
74:02F-008
Green, F. H. W.
74:02A-004
Greenkorn, R. A.
74:02G-002
Green, R. E.
74:02G-043
Grewal, S. S.
74:03F-077
Griffin, R. A.
74:02G-033
74:058-026
Grigg, J. L.
74:03F-176
Grimes, D. W.
74:03F-003
Grimsrud, G. P.
74:05A-001
Grobbelaar, H. L.
74:03F-036
Grossi, P.
74:03F-037
Gundlach, 0. L.
74:08B-002
Gupta, S. C.
74:02G-023
74:080-004
Gupta, S. P.
74:02G-002
Gustafson, C. D.
74:03F-013
74:03F-038
74:03F-039
74:03F-055
Guymon, G. L.
74:02G-017
74:02J-005
Haan, C. T.
74:02A-001
184
-------
Hadas, A.
74:03F-163
74:03F-164
Hagan, R. M.
74:03F-001
Hageman, R.
74:03F-089
Haimes, Y. Y.
74:043-003
Hall, B. J.
74:03F-040
74:03F-041
Hall, G. W.
74:050-003
Hall, J. K.
74:058-008
Halvorson, A. D.
74:048-018
Ham, H. H.
74:04A-006
Hanks, R. J.
74:03F-144
Hansen, E. A.
74:02J-004
Hanson, C. L.
74:02J-008
Hanson, E. G.
74:03F-042
Hanway, J. J.
74:058-051
Hargreaves, G. H.
74:058-035
74:060-002
Harms, L. L.
74:058-028
74:058-043
Harrison, o. s.
74:03F-043
Hart, J. S.
74:058-048
Hasfurther, V. R.
74:078-001
Hassan, A. A.
74:02F-014
74:02F-015
Hayslip, N. C.
74:03F-130
Heald, W. R.
74:058-015
Healy, K.A.
74:050-001
Heede, B. H.
74:040-001
Heerman, 0. F.
74:078-003
74:08A-008
Heilman, M. 0.
74:03F-155
Helliwell, D. R.
74:03F-180
74:03F-181
Henderson, D. W.
74:02F-016
Hermann, G. J.
74:03F-150
74:08A-004
Hermsmeier, L. F.
74:048-011
Herrera, I.
74:02F-009
Hiler, E. A.
74:02F-017
74:020-020
74:03F-046
74:03F-099
74:03F-10-4
74:03F-113
74:03F-119
74:03F-147
74:03F-171
74:04A-005
74:08A-002
Hillel, D.
74:03F-068
Hilton, H. W.
74:03F-056
Hoare, E. R.
74:03F-044
Hoffman, D. L.
74:03F-071
Hoffman, G. J.
74:03F-045
74:03F-070
74:048-008
Holloway, M. L.
74:06A-008
Hopson, N. E.
74:050-004
Horcher, F.
74:038-001
Hornberger, G. M.
74:Q5C-003
Horton, M. L.
74:020-003
Howe, C. W.
74:060-003
Howell, T. A.
74:03F-046
74:03F-099
74:03F-104
74:03F-113
74:03F-119
74:03F-147
74:03F-171
74:04A-005
74:08A-002
Huang, C. S.
74:050-004
Huang, W.
74:03F-115
Huang, Y. H.
74:02F-013
Huber, M. J.
74-.03F-088
Buck, P. M.
74:058-016
Hufen, T. H.
74:048-004
Humphrey, W.
74:03F-051
Huntamer, J.
74:03F-007
74:03F-008
74:03F-009
Huntzinger, T. L.
74:06A-005
Hwang, R. B.
74:080-005
Imperato, P.
74:040-005
Ingvalson, R. D.
74:048-020
Iqbal, M.
74:02F-016
Isobe, M.
74:03F-047
185
-------
Jacob, C. E.
74:02F-010
Jackson, R. D.
74:03F-136
Jain, M. L.
74:03F-023
James, L. G.
74:03F-112
Jarboe, J. E.
74:02A-001
Jenne, E. A.
74:05A-002
Jennings, M. E.
74:04A-004
Johanson, S. J.
74:02F-014
74:02F-015
Johnson, C. W.
74:02J-008
Johnson, G. V.
74:02G-036
74:03F-157
Johnson, H. P.
74:060-001
Jones, 0. R.
74:030-004
74:03F-149
Jones, W. C.
74:03F-029
74:03F-030
Jordan, W. R.
74:03F-171
Josan, A. S.
74:03F-077
Joyce, R. T.
74:058-046
Jurinak, J. J.
74:058-026
74:058-029
Kaddah, M. T.
74:048-011
Kanehiro, Y.
74:02G-043
Karamanos, A. J.
74:03F-179
Karlinger, M. R.
74:02E-001
Karmeli, D.
74:03F-048
74:03F-049
74:03F-106
74:03F-153
74:08A-007
Kashef, A-A. I.
74:048-012
Keeney, D. R.
74:04A-007
74:058-050
Keller, J.
74:03F-048
74:03F-049
74:03F-106
Keller, W.
74:03F-166
Kelly, M. G.
74:05C-003
Kenworthy, A. L.
74:03F-050
74:08C-001
Kesner, C.
74:03F-050
74:080-001
Kettel, G. A.
74:058-040
Khanji, J.
74:02G-015
Kharaka, Y. K.
74:02K-001
Kilmer, V. J.
74:058-046
Kimball, 8. A.
74:03F-136
Kirda, C.
74:03F-132
Kirkham D.
74:08A-010
Kisiel, C. C.
74:02E-004
74:06A-010
Kissel, D. E.
74:02G-049
Klausner, S. D.
74:058-010
Kleinecke, D. C.
74:02F-014
74:02F-015
Klemes, V.
74:04A-010
Klepper, B.
74:03F-161
Kliger, L.
74:058-053
Kohl, D. H.
74:058-037
Koluvek, P.
74:08A-001
Konikow, L. F.
74:058-013
Korven, H. C.
74:03F-172
Krans, J. V.
74:02G-036
74:03F-157
Krueger, T. H.
74:058-022
Kruse, E. G.
74:03F-095
Krystal, L.
74:03F-033
Kudo, A.
74:058-048
Kuntze, H.
74:026-037
Laak, R.
74:05D-001
Laflen, J. M.
74:058-051
Lahav, N.
74.-03F-064
Lange, A.
74:03F-007
74:03F-008
74:03F-051
Langer, R. H. M.
74:03F-174
74:03F-175
Larson, C. L.
74:03F-112
Larson, W. E.
74:02G-023
74:078-004
74:080-004
Lattanzi, A. R.
74:fl2J-009
186
-------
Lau, L. S.
74:048-004
Laufer, A.
74:02G-006
Laurenson, E. M.
74:02A-003
Leavitt, G.
74:03F-007
74:03F-008
Levin, I.
74:03F-052
Lewis, R. B.
74:03F-099
Liang, T.
74:03F-115
Liao, C. F.-H.
74:03F-142
Lin, A. C.
74:02F-007
Lindell, D. L.
74:058-036
Lindsey, K. E.
74:03F-053
Lombardo, P. S.
74:058-005
Lombard, P. B.
74:03F-076
Lomen, D. C.
74:03F-127
Lomen, D. O.
74:02G-004
74:03F-085
Long, D. T.
.74:02F-019
Lonnquist, C. G.
74:02E-002
LOtter, D. C.
74:03F-010
Lourens, F.
74:03F-036
Lund, L. J.
74:02G-041
Luthin, J. N.
74:02F-002
74:02G-017
74:080-005
Lutz, J. F.
74:058-046
74:058-054
Lyles, L.
74:03F-155
McCalla, T. M.
74:058-014
McCandless, D. E., Jr..
74:03F-107
McCuen, R. H.
74:02D-001
McDowell, L. L.
74:078-007
McElhoe, B. A.
74:03F-056
McElroy, A. D.
74:058-035
McFarland, J. W.
74:048-006
McHenry, J. R.
74:02J-001
McKerchar, A. I.
74:06A-001
McKyes, E.
74:08A-009
McLaren, A. D.
74:058-017
McMahon, M. A.
74:02G-027
74:048-017
McMaster, G. M.
74:03F-150
74:08A-004
McQueen, I. S.
74:020-001
Maccrimmon, H. R.
74:058-012
MacGregor, J. M.
74:026-044
74:058-024
MacKenzie, A. J.
74:02G-045
74:03F-096
Maddock, T., III
74:02F-005
74:048-005
Matlhi, Y.
74:060-002
Magee, B. H.
74:03F-122
Mahlock, J. L.
74:070003
Mahmood, K.
74:02J-002
Manbeck, D. M.
74:040-004
Manfrinato, H. A.
74:03F-054
Marino, M. A.
74:02F-001
74:058-003
74:058-031
74:058-033
Marsh, A. W.
74:03F-009
74:03F-013
74.-03F-038
74:03F-039
74:03F-055
74:03F-089
Martin, L. W.
74:03F-076
Matheson, W. E.
74:030-002
Mattews, P. J.
74:058-042
Mausel, P. w.
74:078-008
Mawer, P. A.
74:06A-002
Mehdi, S.
74:060-002
Mehdizdeh, P.
74:03F-057
Meek, B. D.
74:02G-045
Mehran, M.
74:02G-047
Mein, R. G.
74:02G-029
Meijer, G.
74:03F-175
Mejia, J. M.
74:02A-002
Mellentin, W. M.
74:03F-076
187
-------
Menzel, R. G.
74:056-047
Merkle, M. G. Jr.
74:058-045
Merrill, S. C.
74:03F-070
Merrill, S. D.
74:03F-045
74:048-008
Meyer, L. D.
74:02J-009
Michener, D. W.
74:03F-004
Mickelson, R. H.
74:08A-008
Middleton, J. E.
74:03F-058
Mikkelsen, D.S..
74:03F-162
74:080-006
Miller, A. C.
74:058-032
Miller, R. F.
74:02G-001
Miller, R. J.
74:02G-007
Minhas, B. S.
74:03F-002
Misra, C.
74:03F-132
74:058-019
74:058-020
74:058-021
Mitchell, P. D.
74:03F-059
Mitchell, P. O.
74:03F-011
Mitchell, R. A.
74:078-008
Miyamoto, S.
74:02G-005
74:02G-026
74:048-016
74:058-025
Mock, T.
74:03F-029
74:03F-030
Moench, A. F.
74:04A-004
Moore, C. V.
74:030-001
Moreau, C. H.
74:04A-002
Morel-Seytoux, H. J,
74:02G-014
74:02G-015
Morteza, H.
74:060002
Mosley, M. P.
74:02J-007
Moss, M. E.
74:02E-001
Mualem, Y.
74:02F-018
Mueller, C. C.
74:04A-001
Mufich, J. G.
74:040-001
Mulford, R. F.
74:03F-122
Muller, A. 8.
74:06A-007
Mulliner, H. R.
74:03F-101
74:03F-110
Murphree, C. E.
74:078-007
Musick, J. T.
74:03F-098
Myers, J. M.
74:03F-043
Nakayama, F. S.
74:03F-015
74:03F-136
Narayanan, A. S.
74:058-030
Nelson, D. W.
74:058-011
Nelson, S. D.
74:048-010
Nelson, W. W.
74:02G-044
Neuman, S. P.
74:02F-011
74:020-039
New, L. L.
74:03F-053
74:03F-060
Nichols, D. G.
74:03F-028
Nicholls, K. H.
74:058-012
Nicholson, H. P.
74:058-006
Nielsen, D. R.
74:03F-132
74:058-018
74:058-019
74:058-020
74:058-021
Nightingale, H.I.
74:048-021
Nofziger, D. L.
74:02G-011
Nordin, C. F.
74:02A-002
Norton, R. D.
74:068-001
Norum, E. 8.
74:058-022
Noyola, F. T.
74:03F-061
Obermueller, A.J,
74:03F-162
74:080-006
Oertli, J.
74:030003
74:03F-133
Olson, T. C.
74:03F-105
Onishi, H.
74:058-030
74:060003
Onstad, C. A.
74:03F-105
Orhun, A.
74:02F-002
Orr, D. V.
74:06D-003
Oster, J. D.
74:03F-045
74:03F-090
74:048-008
74:048-020
188
-------
Ott, R. P.
74:05B-005
Otto, H.
74:03F-051
Ozaki, H. Y.
74:03F-130
paldi, H.
74:03F-062
Palta, J. P.
74:03F-167
Parikh, K. S.
74:03F-002
Parlange, J.-Y.
74:02G-028
74:03F-137
parr, J. F.
74:078-007
partovi, S.
74:060-002
Patrick, W. H. Jr.
74:05B-027
Patterson, T. C.
74:03F-042
74:03F-063
74:048-009
Pearson, R. W.
74:03F-146
peck/ E. L.
74:02G-034
peck, T. R.
74:02G-050
pelleg, D.
74:03F-064
peri/ G.
74:03F-153
74:08A-007
perold, R- P-
74:03F-148
' 74:08A-003
74:088-006
phene, C. J.
74:03F-065
Pidcoe, W. W.
f 74:02F-020
, C. E.
74:02F-014
74:02F-015
Piest, R. F.
74:058-014
74:078-004
Pietsch, M. F.
74:030-002
Pinder, G. F.
74:02F-008
Pionke, H. B.
74:058-004
Pira, E. S.
74:03F-066
74:03F-097
74:03F-117
Pope, P. E.
74:078-005
Porter, R. C.
74:050-002
Powers, W. L.
74:03F-158
Prather, R. J.
74:058-025
Pratt, P. F.
74:02G-041
Prihar, S. S.
74:030005
Proebsting, E. L.
74:03F-058
Pruitt, W. 0.
74:03F-001
Pugh , W. J.
74:03F-019
74:03F-020
Purohit, K. S.
74:03F-097
Qazi, R.
74:048-002
Queck, A. F.
74:02F-016
Raats, P. A. C.
74:02G-025
74:03F-067
74:048-015
Rahman, M. A.
74:02G-020
Ramadan, I.
74:03F-030
Rao, P. S. C.
74:02G-043
Raven, A.
74:048-019
Ravina, I.
74:020-013
Ravschkolb, R. S.
74:03F-071
Rawitz, E.
74:03F-068
Rawlins, S. L.
74:03F-045
74:03F-069
74:03F-070
74:03F-152
74:048-008
Read, A. L.
74:030-002
Reddell, D. L.
74:02F-017
74:03F-113
Reginato, R. J.
74:02G-012
74:03F-136
Reichman, G. A.
74:03F-160
Reinhorn, T.
74:02G-042
Renner, D. M.
74:04A-001
Rhoades, J. D.
74:03F-152
74:048-018
74:04B-020
Richardson, C.
74:058-045
Richardson, E.V.
74:058-032
Ritchie, J. T.
74:02G-049
74:03F-141
74:078-006
Robbins, C. W.
74:058-049
Roberts, R.
74:03F-060
Roberts, S.
74:03F-058
Robertson, W.K.
74:078-005
Rodney, D. R.
74:03F-073
189
-------
Rogers, H. T.
74:03F-146
Rogers, J. S.
74:020-022
74:080-003
Rolfe, G. L.
74:058-044
Rolston, D. E.
74:03F-071
Romkens, M. J.
74:05B-011
Rosenberg, N. J.
74:03F-169
Roth, R. L.
74:03F-072
74:03F-073
Runge, E. C. A.
74:02G-050
Runkles, J. R.
74:02G-020
Rushton, K. R.
74i08B-005
Russo, D.
74:03F-163
74:03F-164
Rydzewski, J. R.
74:060001
Ryther, J. H.
74:050-002
Saffigna, P. G.
74:058-050
Sakka, J. G.
74:088-001
Saleem, z. A.
74:02F-010
74:02F-019
Santillan-Medrano, J.
74:058-029
Sauer, V. B.
74:04A-004
Sawhney, B. L.
74:02G-028
74:03F-137
Saxton, K. E.
74:06D-001
Schade, R. 0.
74:03F-074
Schmer, F. A.
74:078-002
Schmidt, R. L.
74:05C-001
Schroer, F. W.
74:058-022
Schulz, R. K.
74:058-017
Schuman, G. E.
74:058-014
74:058-052
74:078-004
Schwab, G. 0.
74:03F-004
74:03F-107
Scott, W. R.
74:03F-175
Seipt, W. R.
74:03F-100
Second International
Drip Irrigation Congress
74:02G-019
74:03F-006
74:088-003
Sami Selim, M.
74:08A-010
Shamir, U.
74:04A-003
Shani, M.
74:03F-075
Sharma, H. D.
74:03F-151
74:08A-006
Shaw, R. H.
74:060-001
Shearer, G.
74:058-037
Shearer, M. N.
74:03F-076
Shull, H. H.
74:08A-008
Shull, R. D.
74:05A-001
Silos, J. S.
74:068-001
Simpson, C.
74:05A-002
Simundich, T. M.
74:07C-002 '
Sinanuwong, S.
74:03F-131
Sinclair, L. R.
74:020-018
Singh, N. T.
74:03F-077
74:03F-143
Singh, K. P.
74:02E-002
Singh, R. N.
74:06E-001
Sinha, B. K.
74:03F-143
Sly, W. K.
74:03F-182
Skogerboe, G. V.
74:050-001
74:05G-003
74:06A-005
Skopp, J.
74:03F-126
Smajstrla, A. G.
74:02F-017
Smith, R. B.
74:020-007
Smith, S.
74:078-007
Smith, S. J.
74:058-007
Snyder, G. H.
74:03F-130
Snyder, H. H.
74:030001
Soltanpour, P.N.
74:03F-123
Sornsen, R. C.
74:058-036
Spencer, W. F.
74:020-045
74:03F-021
Spomer, R. G.
74:058-014
Spinivasan, T. N.
74:03F-002
Stanford, G.
74:058-023
190
-------
Stanley, H. I.
74:050004
Staple, W. J.
74:03F-135
Starr, J. L.
74:03F-121
74:03F-132
74:056-018
Steele, J. C.
74:03F-103
Steenhuis, T. S.
74:05B-034
Stephen, R. C.
74:03F-176
Stephenson, G. R.
74:02F-012
74:02J-008
Sternberg, Y. M.
74:02G-016
Stevenson, D. S.
74:03F-078
74:03F-178
Stewart, J. I.
74:93F-001
Stone, L. R.
74:020-003
74:03F-158
Stork, K. E.
74:06A-006
Stout, P. R.
74:03F-121
Strelkoff, T.
74:086-001
Streltsova, T. D.
74:048-012
Streutker, A.
74:03F-079
Strohman, R. A.
74:03F-013
74:03F-029
74:03F-030
74:03F-055
Stroosnijder, L.
74:020-030
74:03F-138
suroant, G. -
74:02F-016
74:030-001
Sunada, D. K.
74:056-038
Swank, R. R.,Jr.
74:056-006
Swanson, E. R.
74:056-030
74:06C-003
Swartzendruber, D.
74:020-011
Szigyarto Z.
74:038-001
Tagaments, T.
74:020-016
Tahnoon, S.
74:03F-080
Tait, R. S.
74:03F-078
Takayama, T.
74:058-030
Takeuchi, K.
74:04A-002
Tamaddoni-Jahromi, S.
74:03F-057
Tanji, K. K.
74:02F-016
74:02G-047
Taylor, 8. K.
74:03F-081
Taylor, G. S.
74:080-005
Taylor, H. M.
74:03F-161
Taylor, J. H.
74:050-001
74:05G-003
Tenore, K. R.
74:050-004
74:050-002
Terman, G. L.
74:03F-125
74:03F-134
Thomas, A. W.
74:03F-095
Thomas, G. W.
74:02G-027
74:046-017
74:056-009
74:056-045
Thomas, J. R.
74:03F-155
Thorn, D.
74:06A-002
Thurlow, D. L.
74:03F-145
Tihansky, D. P.
74:050-002
Till, M. R.
74:03F-016
Tischler, L. F.
74:06A-008
Todd, W. J.
74:078-008
Tomlinson, R. T.
74:078-005
Tucker, D. P. H.
74:03F-025
Tucker, J. M.
74:048-020
Tucket, T. C.
74:03F-129
Turner, A.
74:086-005
Uroquhart, N. S.
74:03F-027
Uys, W. J.
74:03F-082
Uzrad, M.
74:03F-035
74:03F-083
Valentine, V. E.
74:050-006
74:058-039
Van der Ploeg,R.R.
74:02G-031
74:03F-139
van Genuchten.MjJTH.
74:048-013
van Schilfgaarde,J.
74:03F-152
Vaziri, C. M.
74-.03F-084
Veldman, G. H.
74:03F-010
Vemuri, v.
74:06A-003
191
-------
Veneman, P. L. M.
74:02G-032
Verhoff, F. H.
74:040-005
Viessman, W.
74:06A-006
Walker, A.
74:02G-048
Walker, W. R.
74:05G-001
74:05G-003
74:06A-005
Walter, M. F.
74:058-034
Wang, W. C.
74:058-002
Warme, W. E.
74:04A-008
Warncke, D. D.
74:03F-183
Warrick, A. W.
74:02G-004
74:02G-005
74:02G-009
74:02G-026
74:03F-085
74:03F-126
74:03F-127
74:03F-128
74:048-016
Weis, G. G.
74:03F-165
Wells, L. G.
74:03F-111
Werner, H. D.
74:078-002
West, D. W.
74:03F-012
Westerman, R. L.
74:03F-129
White, N. F.
74:058-038
Wiens, J. K.
74:03F-172
Wierenga, P. j.
74:03F-063
74:048-009
74:048-013
Wiersma, J. L.
74:03F-120
Wilcox, J. C.
74:03F-182
Wildung, R. E.
74:050-001
Wilke, O. C.
74:03F-086
Wilkinson, K. P.
74:06E-001
Willardson, L. S.
74:03F-087
74:03F-088
74:03F-089
74:03F-090
74:03F-096
74:080-003
Willens, G. A.
74:03F-091
Williams, D. W.
74:03F-114
Willis, G. H.
74:078-007
Willoughby, P.
74:03F-092
Windle, P.
74:058-044
Wischmeier, W. H.
74:02J-006
Wolff, P.
74:03F-093
Workman, O. D.
74:058-004
Wu, I.
74:03F-102
74:03F-115
Wu, I. P.
74:080002
Wu, S-J
74:02F-013
Yagev, E.
74:03F-094
Yakowitz, S. J.
74:02E-004
Yaron, 8.
74:058-053
Yeh, W. W-G.
74:02F-007
Young, E. G.
74:080-001
Yu, W.
74:048-003
Zanker, K.
74:03F-033
Zwerman, P. J.
74:058-010
192
-------
Section XXXIV
SUBJECT INDEX
Abrasion
74:05C-002
Absorption
74:02G-031
74:03F-139
74:03F-142
74:050-001
Adsorption
74:02G-001
74:020-002
74:02G-016
74:02G-033
74:03F-126
74:04B-013
74:058-002
74:056-003
74:058-017
74:058-026
74:058-031
Advection
74:03F-169
Aeration
74:04A-005
Agricultural Runoff
74:058-010
74:058-028
74:078-004
Aaricultural Watersheds
74:058-015
Agriculture
74:02G-018
74:02G-020
74:02J-006
74:03C-001
74:030-002
74:03F-007
74:03E-OQ8
74:03F-010
74:03E-011
74:03E-012
74:03F-013
74:03F-014
74:03E-015
74-.03E-016
74:03E-012
74:03F-018
74:03E-019
74:03F-020
74:03E-021
74:03F-022
74:03F-023
74:03F-025
74:03F-026
74:03F-027
74-.03F-028
74:03F-029
Agriculture
(cont.)
74:03F-031
74:03F-032
74:03F-033
74:03F-034
74:03F-035
74:03F-036
74:03F-037
74:03F-039
74:03F-040
74:03F-041
74:03F-042
74:03F-043
74:03F-044
74:03F-045
74:03F-046
74:03F-047
74:03F-048
74:03F-049
74:03F-051
74:03F-052
74:03F-053
74:03F-054
74:03F-055
74:03F-056
74:03F-058
. 74-.03F-059
74:03F-060
74:03F-061
74:03F-062
74:03F-063
74:03F-064
74:03F-066
74:03F-067
74:03F-068
74:03F-069
74:03F-070
74:03F-071
74:03F-072
74:03F-073
74:03F-074
74:03F-075
74:03F-076
74:03F-077
74:03F-078
74-.03F-079
74:03F-080
74:03F-081
74:03F-082
74:03F-083
74:03F-084
74-.03F-085
74:03F-086
74:03F-087
74:03F-088
74:03F-089
74:03F-090
74:03F-091
74:03F-092
74:03F-093
74:03F-094
74:03F-095
Agriculture
(cont.)
74:03F-096
74:03F-097
74:03F-098
74:03F-099
74:03F-100
74:03F-101
74:03F-102
74:03F-104
74:03F-105
74:03F-106
74:03F-117
74:03F-127
74:03F-128
74:03F-154
74:03F-177
74:04A-OQQ
74:04A-011
74:048-006
74:048-008
74:048-009
74:048-010
74:048-011
74:058-010
74:058-035
74:05G-003
74:060-001
74:06D-rOG2
74:02BT001
74:078-002
74:088-004
74:08C-001
74:080002
74:080-003
Agronomic Crops
74:03F-105
74:03F-175
Air Pollutants
74:058-025
Air Temperature
74:03F-055
74:078-001
Alaska
74:02G-017
74:02J-005
Alfalfa
74:63F-002
74:03F-087
74:03F-089
74:03F-160
74:03F-169
74:048-020
74:058-008
Algae
74:050-003
74:050-002
193
-------
Algal Control
74:050004
Algorithms
74:04A-002
74:06A-002
Alkalinity
74:03F-168
Alluvial Aquifers
74:048-002
Alluvial Channels
74:02F-003
74:058-013
Alternative Planning
74:040-004
Ammonia
74:02K-001
74:058-017
74:058-018
74:058-019
74:058-020
74:058-021
74:058-024
74:058-052
Ammonification
74:058-037
Ammonium Compound
74:03F-129
74:03F-184
Anaerobic Conditions
74:058-027
Analytical Techniques
74:02A-003
74:02E-002
74:03F-002
74:048-006
74:05A-002
74:058-042
74:06A-008
Anion Exchange
74:058-007
Anions
74:02G-027
74:048-017
Anisotrophy
74:02F-013
Antecedent Moisture
Content
74:020-008
Application Equipment
74:03F-020
74:050-003
74:078-003
Application Methods
74:03F-153
74:050-003
74:078-003
74:08A-007
Aquatic Environment
74:058-042
74:05C-005
Aquatic Life
74:05C-005
Aquatic Plants
74:05C-005
Aquatic Weed Control
74:05C-005
Aquatic Weeds
74:05C-005
Aqueous Solutions
74:02C-001
Aquifer Characteristics
74:02F-006
74:02F-007
74:02F-010
74:02F-018
74:02F-020
Aquifers
74:02F-018
74:02F-019
74:058-054
74:088-005
Aquifer Systems
74:02F-010
74:02F-018
Aquifer Testing
74:02F-005
74:02F-020
Aquifers
74:02F-005
74:02F-007
74:02F-013
74:02F-014
74:02F-015
74:02F-020
74:02G-014
74:088-002
Aquitards
74:02F-009
Apple
74:03F-012
74:03F-028
74:03F-052
74:03F-081
Artie
74:02G-017
Arizona
Artesian Aquifers
74:02F-010
74:048-012
Artesian Wells
74:02F-013
74:048-012
Artificial Re-
charge
74:048-005
74:048-007
Asphalt
74:03F-167
Attitudes
74:06E-001
Australia
74:03F-177
Automatic Control
74:03F-060
Automation
74:020-037
74:03F-060
74:03F-062
74:03F-065
74:03F-141
74:078-006
Available Watej?
74:03F-167
Bacteria
74:03F-056
74:058-028
Backfill
74:08D-005
Barley
74:03F-156
74:048-011
Barriers
74:03F-167
Base Flow
74:02F-012
74:04A-004
Bed Load
74:02J-002
74:02J-004
Bed Load Samplers
74:02J-004
Benefits
74:048-006
74:040-001
Bentonite
74:058-002
74:04D-001
194
-------
Bioassays
74:050004
Biochemical Oxygen Demand
74:026-046
74:05B-001
74:058-005
Biodegradation
74:058-007
74:05B-017
Bioindicators
74:058-028
Biological Communities
74:05B-040
74:05C-001
74:050-003
Biological Properties
74:050-004
Canal Seepage
74:03P-151
74:08A-006
Canals
Citrus Fruits
74:03F-010
74:03F-043
74:04B-010
74:02J-002
74:048-002
Clays
Capillary Action
74:02G-001
74:02G-029
Capillary Conductivity
74:026-015
Capillary Water
74:02G-018
74:02G-013
74:02K-001
Biomass
Boron
74:05C-003
74:020-033
74:05B-042
Bromegrass
74:03F-183
74:060-001
Bromides
74:058-007
Bromine
74:02K-001
Bulk Density
74:02G-012
Cadmium
74:056-029
Calcareous Soils
74:058-025
Calcite
74:058-026
Calcium
74:02K-001
California
74:02F-014
74:02F-015
74:02F-016
74:02K-001
74:03C-001
74:03F-114
Canada
74:02E-003
74:03F-078
74:03F-182
74:058-012
Capital
74:048-006
Carbon
74:02G-045
74:05C-001
74:05C-003
Carbon Dioxide
74:02G-008
74:05C-003
Carbonates
74:02F-019
Cation Exchange
74:020-013
Channels
74:02J-004
Check Structures
74:040-001
Chemical Analysis
74:05A-002
Chemical Oxygen Demand
74:020-046
Chemical Potential
74:020-013
Chemical Properties
74:048-004
Chemistry
74:048-004
74:05B-028
Chlorides
74:02F-014
74:020-006
74:020-027
74:020-049
74:02K-001
74:048-017
74:058-016
74:05B-022
74:058-050
Cleaning
74:088-004
74:08C-003
Climates
74:02A-004
Climatic Data
74:02A-004
74:058-005
74:060-002
74:078-004
Clogging
74:020-046
74:03C-002
74:03F-025
74:03F-064
74:03F-069
74:03F-082
74:05C-002
Coagulation
74:03F-026
Coasts
74:05C-004
Cobalt
74:05A-002
Colorado
74:046-002
74:040-001
74:058-013
74:058-038
74:050-001
74:050-003
Colorado River
74:03C-001
74:058-039
74:05C-006
74:050-001
74:060-003
Colorado River
Basin
74:058-039
74:05C-006
74:060-003
Community Devel-
opment
74:08A-005
Compacted Soils
74:080-005
195
-------
Compaction
74:080-005
Comparative Productivity
74:03F-014
Computer Models
74:02F-007
74:02F-013
74:02G-017
74:026-031
74:020-047
74:020-048
74:03F-112
74:03F-139
74:03F-144
74:048-002
74:060-001
Computer Programs
74:02E-002
74:02F-013
74:02F-015
74:02F-017
74:03F-104
74:03F-139
74:04A-001
74:04A-003
74:04A-004
74:040-001
74:05C-002
Computers
74:020-023
74:080-004
Concrete Construction
74:08A-001
Concret-Lined Canals
74:08A-001
Concrete Structures
74:08A-001
Conduction
74:020-017
Conductivity
74:080-001
Conduits
74:08B-002
Confined Water
74:02F-010
Conjuctive Use
74:04B-002
74:043-003
74:048-005
74:058-013
Connecticut
74:050-001
Connection
74:03F-126
Conservation
74.-03F-180
74:03F-181
74:06C-003
Constraints
74:04A-003
74:04D-004
Construction
74:02J-006
74:03F-107
74:03F-108
Construction Cost
74:040-001
Consumptive Use
74:020-004
74:03.F-014
74:03F-015
74:03F-155
74:03F-103
74:03F-144
74:03F-154
74:03F-172
74:03F-182
Contour Farming
74:058-014
Convection
74:02G-006
74:020-016
Copper
74:05A-002
Corn
74:020-044
74:03F-101
74:03F-105
74:03F-110
74:03F-120
74.-03F-125
74:03F-140
74:03F-142
74:03F-156
74:03F-160
74:03F-170
74:03F-183
74.-04A-005
74:058-044
74:060-001
Corn (Field)
74:03F-001
74:058-008
Corn Root Zone
74:03F-143.
Correlation Analysis
74:02E-002
74:058-047
Corrosion
74:05C-002
Cost Analysis
74:03F-070
74:03F-172
74:040-001
74:06C-001
74:06C-002
74:060-003
Cost-Benefit
Analysis
74:05A-001
Cost Comparisons
74:03F-039
74:03F-070
Costs
74:04A-001
74:04A-003
74:048-006
74:058-001
74:05C-002
74:06C-002
74:060-003
Cotton
74:03F-014
74:03F-079
74:03F-087
74:03F-159
74:03F-161
74:04A-005
74:06A-007
Crop Production
74:030-005
74:03F-007
74:03F-060
74:03F-061
74:03F-076
74:03F-079
74:03F-083
74:03F-099
74:03F-105
74:03F-114
74:03F-118
74:03F-154
74:03F-162
74:03F-173
74:048-011
74:080-006
Crop Productivity
74:03C-003
74:03F-039
74:03F-133
74:03F-134
Crop Response
74:020-019
74:03C-003
74:030-005
74:03F-002
74:03F-004
74:03F-006
74:03F-007
74:03F-014
74:-03F-015
196
-------
Crop Response
(cont.)
74:03F-016
74:03F-017
74:03F-018
74:03F-027
74:03F-032
74:03F-039
74:03F-040
74:03F-041
74:03F-042
74:03F-043
74:03F-045
74:03F-052
74:03F-053
74:03F-057
74:03F-058
74:03F-059
74:03F-061
74:03F-065
74:03F-068
74:03F-074
74:03F-076
74:03F-077
74:03F-081
74:03F-087
74:03F-088
74:03F-089
74:03F-090
74:03F-091
74:03F-092
74:03F-093
74:03F-094
74:03F-098
74:03F-103
74:03F-105
74:03F-120
74:03F-121
74:03F-122
74:03F-123
74:03F-125
74:03F-133
74:03F-140
74:03F-142
74:03F-145
74:03F-146
74:03F-154
74:03F-155
74:03F-156
74:03F-159
74:03F-161
74-.03F-162
74:03F-165
74:03F-166
74:03F-168
74:03F-170
74:03F-173
74:03F-174
74:03F-176
74:03F-177
74:03F-179
74:03F-183
74:04A-005
74:058-044
74:08B-003
74:080-006
Crops
74:058-010
74:058-030
Cultivation
74:02G-042
74:05B-054
Currents (Water)
74:02J-004
Damages
Dams
74:048-002
74:05C-002
74:080-001
Darcy's Law
74:02G-017
Data Collections
74:02F-002
74:02F-014
74:078-003
74:07C-002
74:07C-003
Data Processing
74:02F-002
74:05A-001
Decision Making
74:04A-002
74:06A-002
Deep Percolation
74:05G-001
Denitrification
74:02G-041
74:02G-044
74:020-045
74:02G-047
74:03F-132
74:04A-007
74:048-019
74:05A-003
74:058-017
74:058-018
74:058-019
74:058-020
74:058-021
74:058-023
74:058-024
74:058-054
Depth
74:04A-001
Deserts
74:03F-091
Design
74:02G-019
74:03F-006
74:03P-104
74:04A-001
Design
(cont.)
74:04A-003
74:040-004
74:088-003
74:08C-002
Design Criteria
74:02G-014
74:026-019
74:03F-006
74:03F-046
74:03F-049
74:03F-066
74:03F-068
74:03F-097
74:03F-103
74:03F-106
74:03F-117
74:088-003
74:08C-002
Design Flow
74:02G-019
74:03F-006
74:03F-046
74:03F-106
74:08A-008
74:088-003
74:08C-002
Desilting
74:02J-Q01
Diffusion
74:02G-011
74:02G-040
74:03F-126
74:03F-132
74:03F-142
74:058-018
74:058-019
74:058-020
74:058-021
74:058-032
Diffusivity
74:020-002
74:02F-007
74:020-011
74:02G-023
74:020-024
74:020-030
74:03F-136
74:03F-138
74:048-014
74:080-004
Digital Computers
74:02F-013
Discharge Mea-
surement
74:02J-004
Discharge (Water)
74:02F-003
74:02F-006
197
-------
Discharge (Water)
(cont.)
74:050-004
74:088-002
Diseases
74:03F-008
74:03F-039
Disease Resistance
74:03F-008
Disinfection
74:03F-083
Dispersion
74-.02F-015
74:02G-002
74:020-006
74:020-016
74:05B-003
74:056-022
74:058-031
74:058-032
74:058-033
Disposal
74:050-001
Dissolved Oxygen
74:058-001
74:058-016
Dissolved Solids
74:02F-014
74:02F-015
74:058-005
74:058-013
Distribution Patterns
74:02E-002
Diurnal
74:03F-027
Domestic Wastes
74:050-001
Domestic Water
74:05C-002
Downstream
74:048-006
Drainage
74:020-014
74:02G-037
74:020-038
74:020-044
74:03F-004
74:03F-107
74:03F-116
74:03F-160
74:04A-OQ5
74:048-020
74:05A-003
74:058-046
74:08A-009
Drainage Effects
74:02A-004
74:03F-151
74:03F-160
74:04A-005
74:058-040
74:08A-006
74:08A-009
Drainage Engineering
74:020-037
74:03F-004
74:03F-107
74:04A-006
74:08A-009
74:080-005
Drainage Practices
74:020-037
74:020-038
74:03F-107
74:03F-151
74:04A-005
74:04A-006
74:058-040
74:08A-006
74:08A-009
74:088-004
74:08C-003
74:080-005
Drainage Systems
74:02A-004
74:04A-001
74:04A-006
74:088-004
74:08C-003
Drainage Water
74:020-026
74:020-049
74:048-016
74:048-020
74:058-040
74:058-049
Drainage Wells
74:04A-006
Drains
74:020-037
74:08A-009
74:088-004
74:080-003
74:080-005
Drawdown
74:02F-005
74:02F-009
74:02F-010
74:02F-013
74:048-001
74:048-002
74:048-005
74:088-005
Drought Resistance
74:03F-167
Droughts
74:03F-001
74:03F-167
Dry Farming
74:03F-159
Drying
74:020-007
74:03F-135
Dupuit-Forchhei-
mer Theory
74:048-007
74:080-001
Dynamic Program-
ming
74:03F-113
74:04A-002
74:058-001
74:06A-002
Dynamics
74:040-005
74:06C-001
Economic Effi-
ciency
74:04A-002
74:048-006
Economics
74:020-019
74:03F-006
74:03F-049
74:03F-148
74:04A-003
74:048-006
74:050002
74:050-002
74:06A-007
74:08A-003
74:08A-005
74:088-003
74:088-006
Ecosystems
74:050-002
74:060-001
Effluents
74:020-046
74:030-002
74:050-001
74:050-002
Electrical Con-
ductance
74:048^-018
Electrolytes
74:020-020
Energy
74:03F-109
Energy Budget
74:03F-169
198
-------
Engineers Estimates
74:040-001
Environment
74:06E-001
Environmental Control
74:06E-001
74:078-008
Environmental Effects
74:02A-004
Environmental Engineer-
ing
74:050-001
74:070003
Equations
74:020001
74:020-001
74:020-002
74:02F-001
74:02F-005
74:02F-010
74:02G-001
74:02G-009
74:020-011
74:02G-016
74:026-017
74:02J-003
74:02J-005
74:03F-124
74:04A-001
74:04A-002
74:04A-003
74:048-002
74:048-006
74:058-005
74:058-018
74:058-019
74:058-020
74:058-021
74:058-031
74:058-033
74:050003
74:06A-003
74:070003
Equipment
74:03F-020
74:03F-179
74:078-007
Erosion
74:02J-001
74:02J-003
74:02J-006
74:02J-007
74:02J-009
74:058-006
74:058-011
74:058-028
74:058-043
74:058-047
74:058-049
74:060003
Erosion Control
74:02J-009
74:040-001
Erosion Rates
74:02J-007
74:02J-009
Estimating
74:03C-001
74:03F-002
74:070003
Eutrophication
74:058-010
74:050001
74:050003
74:06A-004
Evaluation
74:02J-006
74:03F-048
74:03F-172
74:048-002
74:058-005
74:058-030
Evaporation
74:020-001
74:020-002
74:03F-055
74:03F-059
74:03F-135
74:03F-136
74:03F-141
74:03F-144
74:03F-166
74:058-004
74:060-001
74:060-002
74:078-006
Evaporation Control
74:03F-166
Evaporation Pans
74:02G-019
74:03F-006
74:03F-009
74:03F-010
74:060-002
74:088-003
Evapotranspiration
74:020-002
74:020-004
74:02G-039
74:03F-001
74:03F-002
74:03F-049
74:03F-118
74:03F-119
74:03F-141
74:03F-142
74:03F-154
74:03F-169
74:060-001
74:060-002
74:078-006
Expansive Soils
74:02G-012
Farm Management
' 74:058-014
Farms
74:030001
Feed Lots
74:026-045
Fertility
74:03F-123
74:03F-155
Fertilization
74:02A-004
74:026-019
74:026-036
74:026-044
74:026-050
74:03F-006
74:03F-010
74:03F-017
74:03F-028
74:03F-036
74:03F-041
74:03F-047
74:03F-053
74:03F-071
74:03F-073
74:03F-075
74:03F-105
74:03F-110
74:03F-121
74:03F-122
74:03F-124
74:03F-150
74:03F-155
74S03F-156
74:03F-157
74:03F-166
74:03F-174
74:03F-175
74:03F-176
74:03F-177
74:03F-183
74:058-010
74:058-036
74:058-046
74:058-050
74:058-051
74:08A-004
74:088-003
Fertilizers
74:02A-004
74:026-026
74:026-044
74:026-050
74:03F-071
74:03F-073
74:03F-110
74:03F-123
74:03F-124
74:03F-125
74:03F-150
74:03F-155
199
-------
Fertilizers
(cont.)
74:03F-174
74:03F-175
74:03F-176
74:03F-183
73:03F-184
74:048-016
74:058-009
74:058-011
74:058-012
74:058-015
74:058-024
74:058-036
74:058-038
74:058-046
74:058-050
74:058-051
74:08A-004
Films
74:078-002
Filters
74:078-002
Filtration
74:03F-010
74:03F-026
74:03F-048
74:03F-075
74:03F-076
74:08A-009
Finite Element Analysis
74:02F-004
74:02F-008
74:02F-013
74:026-016
Flame Photometry
74:05A-002
Flocculation
74:03F-026
Flood Control
74:058-004
Flood Frequency
74:02A-003
Flooding
74:03F-134
Flood Irrigation
74:03F-134
74:03F-162
74:080-006
Flood Peak
74:02A-003
Florida
Flow
74:03F-043
74:088-004
74:04A-003
Flow
(cont.)
74:048-002
Flow Characteristics
74:03F-020
74:03F-100
74:03F-106
Flow Data
74:06A-001
Flow Measurement
74:02G-021
74:080-002
Flow Nets
74:050-001
Flow Rates
74:03F-020
74:03F-049
74:03F-066
74:03F-072
74:03F-079
74:03F-082
74:03F-097
74:03F-117
74:08A-008
74:08C-001
Flow Resistance
74:058-032
Flow System
74:02F-006
Flow Systems
74:04A-006
Fluid Movement
74:02G-016
74:058-031
Food Chains
74:050-002
Food Webs
74:050-002
Forecasting
74:06A-001
Forest Management
74:03F-057
Forestry
74:03F-057
74:03F-080
Forests
74:03F-057
Free Energy
74:020-013
74:058-026
Free Surface
74:02G-003
Free Surfaced
74:048-012
Freezing
74:02C-001
74:02G-017
Frequency
74:03F-009
74:03F-014
74:03F-015
74:03F-052
74:03F-096
Freshwater
74:02F-018
Frost Heaving
74:02G-017
Frozen Ground
74:02C-001
Frozen Soils
74:02C-001
74:02G-017
Fruit Crops
74:03F-058
Fungicides
74:03F-008
Furrow Irrigation
74:02G-019
74:03F-006
74:03F-007
74:03F-014
74:03F-015
74:03F-019
74:03F-027
74:03F-032
74:03F-040
74:03F-041
74:03F-042
74:03F-057
74:03F-065
74:03F-077
74:03F-088
74:03F-098
74:03F-101
74:03F-170
74:088-001
74:088-003
Furrows
74:03F-098
Furrow Systems
74:03F-098
Gamma Rays
74:02G-012
Geochemistry
74:02K-001
Geohydrology
74:048-004
200
-------
Germination
74:030-003
74:03F-087
74:03P-133
74:03F-163
74:03F-164
74:03F-168
Glacial Aquifers
74:02P-006
Glaciohydrology
74:020-002
74:02J-005
Grain Sorghum
74:03F-045
74:03F-098
74:03F-119
74:04A-005
74:048-008
74:076-002
Gravimetric Analysis
74:02G-007
Greenhouses
74:03F-029
74:03F-030
74:03F-060
74:03F-134
Groundwater
74:02F-001
74:02F-007
74:02F-013
74:02F-018
74:02F-019
74:02G-003
74:02G-038
74:02G-042
74:020-043
74:020-049
74:020-050
74:03C-005
74:03F-149
74:04B-002
74:04B-004
74:04B-012
74:048-021
74:058-029
74:058-034
74:058-038
74:058-046
74:058-050
74:058-054
74:05C-003
74:06A-007
74:088-005
Groundwater Basins
74:02F-004
74:02F-015
74:030-004
74:03F-149
Groundwater Movement
74-.02F-002
74:02F-004
Groundwater Movement
(cont.)
74:02F-006
74:02F-008
74:02F-011
74:02F-012
74:02F-014
74:02F-015
74:02G-002
74:02G-004
74:02G-021
74:02G-038
74:048-001
74:048-007
74:058-003
74:058-013
74:058-031
74:058-033
74:088-002
74:088-005
74:08D-001
74:080-002
Groundwater Recharge
74:020-021
74:030-004
74:03F-149
74:048-007
74:058-038
74:050-001
74:06A-007
74:080-002
Groundwater Resources
74:048-003
74:048-006
Growth Rates
74:03F-059 >
74:03F-144
74:050-003
Growth Stages
74:03F-146
Gully Erosion
74:040-001
Hawaii
74:03F-047
74:03F-131
74:048-004
Head Loss
74:03F-066
74:03F-097
74:03F-117
Heat Budget
74:02D-001
Heat Flow
74:02F-006
Heat Transfer
74:020-001
Heavy Metals
74:058-029
Heavy Metals
(cont.)
74:058-044
Herbicides
74:020-043
74:02G-048
74:03F-051
74:048-013
74:058-008
74:058-045
74:050-005
Heterogeneity
74:02F-013
High Pressure
74:080-003
History
74:03F-038
74:03F-068
Horticultural
Crops
74:03F-029
Humid Area
74:03F-043
Hydraulic Con-
ductivity
74:02F-004
74:020-004
74:020-008
74:020-009
74:020-015
74:020-017
74:02G-018
74:020-020
74:020-024
74:02G-025
74:020-029
74:020-032
74:Q3F-111
74:03F-163
74:03F-164
74:04A-001
74:048-014
74:048-015
74:050-001
74:080-005
Hydraulic Con-
duits
74:03F-100
Hydraulic Design
74:03F-023
74:03F-033
74:03F-084
74:03F-100
74:03F-104
74:03F-147
74:08A-002
74:08A-010
74:088-006
74:08C-002
201
-------
Hydraulic Equipment
74:03P-023
74:03F-033
74:03F-100
74:08A-010
74:08C-003
Hydraulic Machinery
74:080-003
Hydraulic Models
74:02P-002
74:048-007
Hydraulic Properties
74:02G-019
74:03F-006
74:03F-033
74:03F-084
74:03F-104
74:08A-010
74:083-003
Hydraulics
74:03F-023
74:03F-033
74:03F-084
74:04A-003
74:08B-006
74:08C-002
74:08C-003
74:080-001
Hydraulic Structures
74:03F-100
Hydrodynamics
74:088-001
Hydrogen
74:058-036
Hydrogen Ion Concen-
tration
74:053-027
Hydrogeology
74:02F-016
74:058-009
Hydrograph Analysis
74:04A-004
Hydrologic Aspects
74:058-040
74:06A-001
Hydrologic Data
74:02E-002
74:058-005
74:06A-001
74:060-001
74:07C-002
Hydrologic Models
74:02A-003
Hydrologic Systems
74:02A-003
Hydrologic Systems
(cont.)
74:058-040
74:06D-001
Hydrology
74:02E-004
74:04A-010
74:058-038
74:06A-010
74:078-008
Idaho
74:02F-012
74s02J-008
Illinois
74:02E-002
74:02F-006
74:05A-001
74:058-002
74:058-030
Imported Water
74:048-003
Impoundments
74:058-004
Income
74:058-030
Indiana
74:05A-001
Industrial Wastes
74:058-029
74:05G-002
Industrial Water
74:048-003
Infiltration
74:020002
74:02F-012
74:02F-017
74:02G-005
74:020-009
74:02G-010
74:02G-019
74:020-020
74:02G-024
74:02G-028
74:02J-009
74:03F-005
74:03F-006
74:03F-054
74:03F-067
74:03F-095
74:03F-112
74:03F-127
74:03F-128
74:03F-137
74:048-014
74:050-001
74:083-001
74:088-003
Infiltration
Rates
74.-02G-015
74:02G-020
74.-03F-098
74:03F-112
Inflow
74:04A-002
74:06A-002
Information Re-
trieval
74:07C-003
Infrared Radia-
tion
74:078-002
Input-Output
Analysis
74:070001
Instrumentation
74:020-004
74:02G-007
74:02G-010
Inter-Basin
Transfers
74:02E-001
Iodine
74:02K-001
lonization
74:020-013
Ion Exchange
74:02G-006
74:02G-013
74:02K-001
Ion Transport
74:02G-006
74:053-029
Ions
Iowa
Iron
74:02F-019
74:93F-143
74:053-014
74:053-027
Iron Bacteria
74:03F-025
Irrigated Land
74:030001
74:04A-001
Irrigation
74:020-004
74:02F-001
74:020-009
74:026-043
202
-------
Irrigation
(cont.)
74:02G-045
74:030002
74:03F-005
74:03F-007
74:03P-008
74:03F-010
74:03F-011
74:03F-012
74:03F-013
74:03F-014
74.-03F-015
74:03F-016
74:03F-017
74:03F-018
74:03F-019
74:03F-020
74:03F-021
74:03F-022
74:03F-023
74:03F-024
74:03F-025
74:03F-026
74:03F-027
74:03F-028
74:03F-029
74:03F-031
74:03F-032
74:03F-033
74:03F-034
74:03F-035
74:03F-036
74:03F-037
74:03F-039
74:03F-040
74:03F-041
74:03F-042
74:03F-043
74:03F-044
74:03F-045
74:03F-046
74:03F-047
74:03F-048
74:03F-049
74:03F-051
74:03F-052
74:03F-053
74:03F-055
74:03F-056
74:03F-057
74:03F-058
74:03F-059
74:03F-060
74:03F-061
74:03F-062
74:03F-063
74:03F-064
74:03F-066
74:03F-067
74:03F-068
74:03F-069
74:03F-070
74:03F-071
74:03F-072
74:03F-073
74:03F-074
74:03F-075
74:03F-076
Irrigation
(cont.)
74:03F-077
74:03F-078
74:03F-079
74:03F-080
74:03F-081
74:03F-082
74:03F-083
74:03F-084
74:03F-085
74:03F-086
74:03F-087
74:03F-088
74:03F-089
74:03F-090
74:03F-091
74:03F-092
74:03F-093
74:03F-094
74:03F-095
74:03F-096
74:03F-097
74:03F-098
74:03F-099
74:03F-100
74:03F-101
74:03F-102
74:03F-104
74:03F-106
74:03F-109
74:03F-110
74:03F-111
74:03F-117
74:03F-118
74:03F-119
74:03F-127
78:03F-128
74:03F-146
74:03F-150
74:03F-154
74:03F-158
74:03F-159
74:03F-169
74:03F-171
74:03F-173
74:03F-179
74:04A-008
74:04A-011
74:048-006
74:048-008
74:048-009
74:048-010
74:048-011
74:048-019
74:048-020
74:048-021
74:048-050
74:040-002
74:05D-003
74:050-001
74:05G-003
74:068-001
74:06C-001
74:060002
74:078-002
74:078-003
74:08A-004
74:08A-005
Irrigation
(cont.)
74:088-006
74:080001
74:080002
Irrigation Canals
74:038-001
74:08A-001
Irrigatio
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
in Design
03F-009
03F-015
03F-016
03F-023
03F-034
03F-043
03F-044
03F-046
03F-049
03F-066
03F-070
03F-084
03F-086
03F-097
03F-100
03F-102
03F-103
03F-104
03F-106
03F-111
03F-117
03F-118
03F-147
03F-148
03F-153
03F-178
08A-002
08A-003
08A-005
08A-007
08A-008
088-006
08C-001
Irrigation Dis-
tricts
74:068-001
74:060002
Irrigation Ef-
fects
74:02G-001
74:020-012
74:02G-019
74:038-001
74:03F-003
74:03F-092
74:03F-096
74:03F-098
74:03F-I01
74:03F-127
74:03F-128
74:03F-146
74:03F-152
74:03F-153
74:03F-159
74:03F-170
74:03F-173
203
-------
Irrigation Effects
(cont.)
74:03F-175
74:04A-008
74:048-010
74:04B-011
74:048-019
74:058-024
74:08A-007
74:088-003
Irrigation Efficiency
74:020-019
74:03F-011
74:03F-002
74:03F-006
74-.03F-020
74:03F-034
74:03F-048
74:03F-056
74:03F-065
74:03F-098
74:03F-101
74:03F-154
74:03F-165
74:03F-171
74:03F-178
74:05G-001
74:088-003
Irrigation Engineering
74:03F-147
74:03F-148
74:03F-179
74:08A-001
74-.08A-002
74:08A-003
74:08A-005
74:08A-008
74:088-006
Irrigation Methods
74:03F-066
74:03F-097
74:03F-117
74:03F-144
74:078-003
Irrigation Operation
and Maintenance
74:03F-048
74:03F-086
74:03F-152
Irrigation Operation
and Management
74:03F-096
74-.03F-109
74:048-011
74:05G-003
74s06C-001
Irrigation Practices
74:020-004
74:02G-019
74:030-002
74:03F-005
74:03F-006
74:03F-007
Irrigation Practices
(cont.)
74:03F-008
74.-03F-009
74:03F-015
74:03F-016
74:03F-021
74:03F-027
74-.03F-035
74:03F-036
74:03F-038
74:03F-040
74:03F-042
74:03F-043
74:03F-044
74:03F-045
74:03F-047
74:03F-048
74:03F-050
74-.03F-051
74:03F-052
74:03F-055
74:03F-057
74:03F-058
74:03F-059
74:03F-061
74:03F-063
74:03F-064
74:03F-065
74:03F-068
74-.03F-070
74:03F-071
74:03F-073
74:03F-074
74:03F-075
74:03F-077
74:03F-079
74:03F-083
74-.03F-086
74:03F-087
74:03F-088
74-.03F-089
74:03F-090
74:03F-096
74:03F-098
74:03F-099
74:03F-101
74:03F-103
74:03F-109
74:03F-110
74:03F-119
74:03F-127
74:03F-128
74:03F-144
74:03F-145
74:03F-146
74:03F-150
74:03F-152
74:03F-153
74:03F-154
74:03F-158
74:03F-159
74:03F-160
74:03F-162
74:03F-169
74:03F-170
74:03F-171
74:03F-172
74:03F-175
Irrigation Prac-
tices
74:03F-178
74-.03F-179
74:03F-182
74:04A-011
74:048-008
74:048-009
74:048-010
74:048-011
74:048-020
74:048-021
74:058-049
74:058-050
74:056-053
74:05D-003
74:078-002
74:078-003
74:08A-004
74:08A-007
74:08A-008
74:088-003
74:08D-006
Irrigation Pro-
grams
74:03F-001
74.-04A-008
74:068-001
74:060-001
Irrigation Sys-
tems
74:030-002
74:03F-008
74:03F-009
74-.03F-016
74:03F-034
74:03F-037
74:03F-038
74:03F-040
74:03F-042
74:03F-043
74:03F-044
74-.03F-046
74V03F-048
74:03F-050
74-.03F-052
74:03F-053
74:03F-055
74:03F-056
74:03F-057
74:03F-058
74:03F-059
74:03F-060
74:03F-061
74:03F-062
74:03F-063
74:03F-064
74:03F-065
74:03F-067
74-.03F-068
74:03F-069
74:03F-070
74:03F-071
74:03F-072
74:0-3F-073
74:03F-074
74:03F-075
204
-------
Irrigation Systems
(cont.}
74:03F-076
74:03F-077
74:03F-078
74:03F-079
74:03F-080
74:03F-081
74:03F-082
74:03F-083
74:03F-084
74:03F-085
74:03F-088
74:03F-089
74:03F-090
74:03F-091
74:03F-092
74:03F-093
74:03F-094
74:03F-095
74:03F-102
74:03F-104
74:03F-111
74:03F-119
74:03F-120
74:03F-127
74:03F-128
74:03F-147
74:03F-153
74:03F-154
74:03F-170
74:03F-172
74:03F-178
74:03F-179
74:03F-182
74:04B-009
74:048-010
74:050-003
74:08A-002
74:08A-007
74:08A-008
74:08C-001
74:080-002
Irrigation Water
74:02G-019
74:02J-002
74:03C-001
74:03F-006
74:03F-009
74.-03F-028
74:03F-056
74:03F-110
74:03F-127
74:03F-128
74:03F-150
74:03F-152
74:04B-002
74:048-003
74:048-011
74:058-049
74:050-003
74:05G-001
74:06A-005
74:06C-002
74:08A-004
74:088-002
74:088-003
Irrigation Wells
74:08A-010
Latent Heat
74:03F-169
Iron
74:05A-002
Isotherms
74:02G-002
74:02G-016
74:058-002
Isotopes
74:048-004
Isotope Studies
74:03F-121
Jets
74:088-004
74:08C-003
Kentucky
74:02A-001
74:058-009
Kinetics
74:02G-033
74:058-026
74:058-048
Laboratory Tests
74:020-007
74:020-018
74:058-002
74:050-004
74:078-007
Lake Sediments
74:050001
Lakes
74:050-001
74:050-003
Land Development
74:03F-155
Land Forming
74:03F-155
74:06A-010
Land Management
74:058-014
Land Reclamation
74:03F-091
74:03F-155
Land Use
74:058-009
74:058-015
Landscaping
74:03F-024
74:040-002
Landslides
74:02G-003
Leaching
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
02G-005
02G-006
02G-026
02G-044
02G-049
03F-013
03F-045
03F-130
03F-132
03F-142
048-006
048-008
048-010
048-011
048-016
058-007
058-015
058-018
058-019
058-020
058-021
058-022
058-024
058-029
058-038
058-050
058-053
06A-007
078-005
Lead
74:058-029
74:058-044
Leakage
74:02F-010
Least Squares
Method
74:02F-007
Lettuce
74:03F-045
74:048-008
Linear Program-
ming
74:02F-007
74:030-001
74:03F-115
74:04A-002
74:058-001
74:058-030
74:068-001
74:060-003
Logarithms
74:06A-001
Long-Range Plan-
nig
74:058-005
205
-------
Long-Term Planning
74:06A-002
Lysimeters
74:02D-004
74:02G-049
74:030-005
74:04A-005
74:046-020
74:05B-050
74:06D-002
Magnesium
74:02K-001
Management
74:02F-014
74:02F-015
74:03F-016
74:03F-021
74:03F-083
74:04B-006
74:058-005
74:06A-003
Manganese
74:02G-045
Markov Processes
74:02A-002
74:02E-004
74:04A-010
74:06A-002
Marshes
74:058-012
Mass Transfer
74:02G-016
74:058-031
Materials Testing
74:08A-009
Mathematical Modeling
74:03F-095
Mathematical Models
74:02A-001
74:020-002
74:02F-004
74:02F-008
74:02F-012
74:02F-014
74:02F-015
74:020-003
74:02G-005
74:02G-006
74:02G-016
74:02G-019
74:02G-031
74:02J-003
74:03C-001
74:03F-006
74:03F-034
74:03F-114
74:03F-139
74:04A-002
74:04A-003
Mathematical Models
(cont.)
74:04A-004
74:048-001
74:048-006
74:05A-001
74:053-003
74:058-005
74:058-006
74:058-013
74:06A-002
74.-06A-003
74:078-001
74:070-002
74:088-002
74:088-003
Mathematical
74:020
74:02F
74:02F
74:02F
74:02G
74:02G
74:02G
74:03F
74:03F
74:03F
74:03F
74:04A
74:058
74:058
74:050
74:05G
74:06A
Studies
-001
-005
-007
-010
-003
-004
-040
-085
-095
-127
-128
-010
031
037
003
002
001
Mathematics
74:02F-007
74:02G-003
74.-04A-010
Measurement
74:02J-004
74:03F-001
74:03F-141
74:078-006
Mechanical Properties
74:03F-033
Melons
74:03F-017
74:03F-019
74:03F-035
Melt Water
74:020-002
Melting
74:020-002
Membrane Processes
74:02K-001
Mercury
74:058-048
Meteorological Data
74:02G-048
Meteorology
74:020-001
Methodology
74:020-014
74:020-023
74:03F-002
74:04A-002
74:04A-003
74:048-006
74:06A-003
74:070-003
74:080-004
Michigan
74.-03F-050
74:080-001
Microwaves
74:02G-007
Microorganisms
74:03F-056
Mineralogy
74:058-026
Mist Irrigation
74:03F-170
Mixing
74:03F-150
74:058-032
74:08A-004
Model Studies
74:02A-003
74:020-001
74:02E-002
74:02E-003
74:02F-014
74:02F-017
74:02F-019
74:02G-039
74:02G-047
74:02G-048
74:03F-005
74:03F-111
74:03F-112
74:03F-115
74:03F-126
74:03F-144
74:048-012
74:048-013
74:058-001
74:058-006
74:058-016
74:058-034
74:058-035
74:058-037
74:06A-001
74:06A-004
74:06A-007
74:06A-010
74:060-001
74:06G-001
74:078-001
206
-------
Moisture Availability
74:03F-105
74:03F-118
74:03F-144
74:03F-161
74:03F-165
74:03F-167
Moisture Content
74:02G-001
74:02G-007
74:02G-010
74:020-030
74:020-032
74:03F-054
74:03F-079
74:03F-105
74:03F-138
74:060-001
Moisture Deficit
74-.03F-118
Moisture Stress
74:020-001
74:03F-105
74:03F-144
74:03F-146
74:03F-158
74:03F-163
74:03F-164
74:03F-167
Moisture Tension
74:020-004
74:020-001
74:020-008
74:020-028
74:02E-004
74:03F-137
74:03F-158
74:03F-161
74:03F-165
74:03F-173
74:03F-174
74:056-023
74:060-001
Monitoring
74:03F-013
74:05A-001
74:07B-008
Monte Carlo Method
74:03F-113
Montmori1lonite
74:05B-002
Mulching
74:02J-009
74:03F-130
74:03F-141
74:03F-166
74:07B-006
Multiple-Purpose Pro-
jects
74:04A-002
Municipal Water
74:04B-002
74:04B-003
74:06A-005
Nebraska
74:03F-103
74:03F-169
Network Design
74:02E-001
74:05A-001
New Mexico
74:03F-063
74:048-009
74:040-001
New York
74:05B-010
Nitrites
74:05B-012
Nickel
74:05A-002
Nitrates
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
: 020-002
: 020-027
:020-041
:02G-044
:020-045
: 020-049
:020-050
:03F-142
:03F-183
:04B-017
:04B-019
:05A-003
:05B-007
:05B-009
:05B-012
:05B-017
:05B-022
:05B-024
:05B-030
:05B-034
:05B-050
:05B-052
:05B-054
:06C-003
Nitrification
74:020-047
74:03F-129
74:03F-132
74:03F-134
74:03F-140
74:058-017
74:058-018
74:05B-019
74:058-020
74:058-021
74:058-022
74:058-023
74:058-024
74:058-037
74:058-051
74:050-004
Nitrogen
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
:02G-041
:02G-042
:02G-044
:02G-047
:02G-050
:03F-028
:03F-047
:03F-065
:03F-110
:03F-121
:03F-122
:03F-125
:03F-129
:03F-130
:03F-134
:03F-140
:03F-174
:03F-175
:03F-183
:03F-184
:04A-007
:05A-003
:05B-010
:05B-012
:05B-023
:05B-024
: 058-025
:05B-037
:05B-046
:058-050
: 058-051
:05B-054
:05C-001
:05C-004
:05D-002
:06C-003
:07B-004
Nitrogen Com-
pounds
74:03F-110
Nitrogen Cycle
74:04A-007
Nitrogen Fixation
74:03F-122
Nonpoint Pollu-
tion Source
74:058-028
North Carolina
74:04A-002
74:058-046
74:058-054
Nuclear Moisture
Meters
74:020-012
Numerical Analy-
sis
74:02F-004
74:02F-008
207
-------
Numerical Analysis (cont.)
74:02F-013
74:02G-006
74:02G-016
74:02G-017
74:02J-002
74:048-001
74:05B-003
74:058-013
74:088-001
74:088-005
Nutrient Removal
74:02G-049
74:03F-125
74:058-051
74:058-052
Nutrient Requirement
74:03F-162
74:080-006
Nutrients
74:03F-013
74:03F-030
74:03F-031
74:03F-065
74:03F-081
74:03F-125
74:03F-130
74:03F-140
74:03F-162
74:05B-007
74:058-010
74:058-012
74:058-028
74:058-043
74:058-046
74:058-051
74:06A-004
74:080-006
Observation Wells
74:02F-007
Ohio
74:03F-002
Oil Fields
74:02K-001
Oklahoma
74:03F-124
74:04A-004
74:058-004
Onions
74:03F-042
On-Site Data Collec-
tions
74:02J-004
Open Channel Flow
74:04A-004
74:058-032
74:088-001
Operation and Main-
tenance
74:04A-003
Operations
74:06A-002
Operations Research
74:06A-002
Optimization
74:02A-001
74:02F-007
74:03C-001
74:03F-002
74:03F-099
74:03F-113
74:03F-115
74:04A-002
74:04A-003
74:048-003
74:048-006
74:058-001
74:06A-002
74:06A-003
74:06A-005
74:070-002
Optimum Development
Plans
74:058-005
Optimum Devesedment
Plans
74:03F-001
Oranges
74:03F-007
74:03F-016
74:03F-073
74:03F-094
Orchards
74:02G-019
74:03F-006
74:03F-010
74:03F-011
74:03F-013
74:03F-016
74:03F-028
74:03F-043
74:03F-050
74:03F-051
74:03F-052
74:03F-058
74:03F-059
74:088-003
74:08C-001
Oregon
74:03F-076
74:058-001
74:050-001
Organic Matter
74:02G-042
74:02G-044
74:050-001
Organic Soils
74:02G-042
Orifice Flow
74:02G-019
74:03F-006
74:03F-056
74:083-003
Orifices
74:03F-056
Osmosis
74:020-006
Oxidation
74:05B-017
74:058-018
74:058-019
74:058-020
74:05B-021
74:058-027
Oxidation-Reduc-
tion Potential
74:04A-007
74:058-027
Oysters
74:05D-002
Parametric Hy-
drology
74:02F-007
74:070-002
Parks
74:03F-057
Pastures
74:03F-169
Path of
tants
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
Pollu-
:02G-005
:05B-003
:05B-006
:05B-007
:05B-008
:05B-011
:05B-012
:05B-013
:05B-015
:05B-016
:05B-018
:05B-019
:05B-020
:05B-021
:05B-022
:05B-023
:058-024
:05B-025
:05B-030
:05B-031
:05B-032
:05B-033
Peaches
74:03F-059
208
-------
Peaches
(cont.)
74:03F-092
Pecans
74:03F-053
Penetration
74:03F-007
Pennsylvania
74:056-015
Percolation
74:020002
74:02F-014
74:02G-010
74:02G-011
74:02G-015
74:05B-024
74:050-001
74:088-002
Performance
74:03F-048
74:04A-003
Permafrost
74:02C-001
74:020-017
Permeability
74:02F-009
74:02G-002
74:02G-015
74:02G-018
74:020-020
74:050-001
74:088-002
Permeameters
74:02F-002
Pervious Soils
74:02G-018
Pesticide Kinetics
74:058-006
Pesticide Residues
74:058-008
74:058-053
Pesticide Removal
74:058-053
Pesticides
74:02G-043
74:048-013
74:058-006
74:058-008
74:058-014
74:058-028
74:053-047
74:058-053
74:078-007
Phosphates
74:02G-002
Phosphates
{cont.)
74:03F-081
74:03F-156
74:03F-176
74:058-002
74:058-011
74:058-015
74:058-026
Phosphorus
74:03F-071
74:03F-123
74:03F-124
74:03F-125
74:03F-134
74:040-005
74:058-009
74:058-010
74:058-011
74:058-012
74:058-028
74:05B-043
74:058-046
74:058-049
74:058-051
74:050001
74:050-002
74:06A-004
74:078-004
Phosphorus Compounds
74:058-028
Photosystems
74:058-044
Physical Properties
74:04A-003
Phytoplankton
74:05C-001
Piezometers
74:02F-002
Pine Trees
74:021-002
Pipelines
74:03F-107
74:03F-108
74:08A-005
74:088-006
Pipes
74:04A-003
74:08A-005
74:088-006
Piping Systems
74:03F-148
74:08A-003
74:08A-005
Planning
74:02E-001
74:06A-003
Plant Growth
74:03F-002
74:03F-145
74:03F-159
74:03F-173
74:03F-174
74:03F-175
74:03F-176
74:03F-183
Plant Populations
74:03F-145
74:03F-168
74:03F-180
74:03F-181
Plant Management
74:03F-145
74:03F-159
Plastic Deforma-
tion
74:03F-108
Plastic Pipes
74:03F-107
74:03F-108
Plugging
74:03F-056
Plumbing
74:050002
Pollutant Iden-
tification
74:05A-002
74:058-041
Pollutants
74:048-013
74:040-005
74:058-034
74:058-035
74:058-041
Pollution
74:02G-048
74:058-044
74:058-047
74:058-050
Pollution Abate-
ment
74:050-002
Pollution Taxes
(Charges)
74:050-002
Pores
74:02G-018
Porosity
74:020-018
74:058-023
Porous Media
74:020001
209
-------
Porous Media
(cont.)
74:02F-002
74:02F-017
74:026-002
74.-02G-016
74:02G-018
74:048-007
74:058-003
74:058-031
74:058-033
74:08B-002
74:080-001
Potassium
74:03F-125
74:03F-130
74:058-046
Potatoes
74:030-005
74:03F-077
74:03F-079
74:03F-098
74:03F-120
74:058-053
Precipitation
(Atmospheric)
74:058-052
Pressure
74:030-005
Pressure Head
74:02G-010
74:02G-025
74:048-015
Pressure Measuring
Instruments
74:030-005
Prices
74:030-001
Probability
74:02A-002
74:02E-002
74:06A-002
Productivity
74:050-003
Project Benefits
74:068-001
Project Planning
74:06A-006
74:06A-008
74:060-001
Project Post-Evalua-
tion
74:068-001
Project Purposes
74:06A-006
Projects
74:06A-008
74:060-001
Public Health
74:050-002
Puddling
74:03F-096
Pumping
74:02F-011
74:04B-001
74:048-002
74:048-012
74:088-005
Pumping Plants
74:06A-002
Radioactivity
74:058-047
Radiocarbon
74:048-004
Rainfall
74:03F-105
74:058-028
74:058-043
Rainfall-Runoff Re-
lationships
74:02A-001
74:058-006
74:058-010
Range Management
74:058-045
Rates
74:050-004
Recharge
74:02F-001
74:02F-003
74:02F-006
74:030-004
74:03F-149
74:048-001
74:048-002
74:048-003
Recharge Ponds
74:030-004
74:03F-149
Reclamation
74:03F-168
Recycling
74:050-002
Reduction (Chemical)
74:058-018
74:058-019
74:058-020
74:058-021
74:058-027
Reflectance
74:078-002
Regional Analy-
sis
74:030-001
Regression Analy-
sis
74:02A-002
74:02E-001
74:02J-005
74:058-023
74:070-003
Reliability
74:06A-002
Remote Sensing
74:078-002
Research
74:03F-001
Research And De-
velopment
74:06A-006
Research Equip-
ment
74:078-003
Research Prior-
ities
74:06A-006
Reservoir Design
74:02J-001
Reservoir Opera-
tion
74:02J-001
74:04A-002
Reservoir Re-
leases
74:06A-003
Reservoir Silt-
ing
74:02J-001
Reservoir Storage
74:04A-002
74:048-002
74:06A-003
Reservoirs
74:04A-003
74:058-004
74:06A-002
74:060-003
Retention
74:040-004
Return Flow
74:020-003
74:02J-010
210
-------
Return Flow
(cont.)
74:03F-006
74:03F-063
74:04A-011
74:04B-009
74:048-020
74:058-013
74:050-001
74:088-003
Reviews
74:02J-003
Rice
74:03F-134
74:03F-162
74:03F-168
74:080-006
Rill Erosion
74:02J-007
River Basin Develop-
ment
74:04A-002
River Basins
74:058-001
74:058-005
River Forecasting
74:02E-003
River Flow
74:02E-003
74:04D-005
River Systems
74:02E-003
Rivers
74:02E-003
74:048-002
74:040-005
74:058-048
74:050-003
74:06A-002
Rocky Mountain Region
74:040-001
Root Development
74:02G-019
74:02G-036
74:03F-006
74:03F-011
74:03F-012
74:03F-081
74:03F-092
74:03F-094
74:03F-157
74:03F-161
74:03F-177
74:088-003
Root Development
Irrigation
74:03F-030
Root Distribution
74:03F-011
74:03F-059
74:03F-088
74:03F-092
74:03F-162
74:080-006
Root System
74:020-025
74:020-039
74:03F-028
74:03F-092
74:03F-161
74:048-015
Root Zone
74:020-025
74:020-039
74:048-015
Rotation
74:058-010
Roughness (Hydraulic)
74:02J-004
Routing
74:02J-002
74:04A-004
Runoff
74:02J-008
74:02J-009
74:02J-010
74:040-005
74:058-006
74:058-008
74:058-012
74:058-043
74:058-045
74:058-046
74:058-047
74:053-051
74:058-052
74:050001
74:06A-010
Saline Soil
74:021-002
74:03F-045
74:03F-063
74:03F-073
74:03F-079
74:03F-090
74:03F-094
74:03F-143
74:03F-152
74-.03F-156
74:03F-168
74:030-005
74:048-008
74:048-009
74:048-010
74:048-020
74:058-039
74:050006
74:06A-007
Saline Soils
74:050-001
74:050-003
Saline Water
74:020001
74:02F-016
74-.02F-018
74:020-001
74:020-003
74:020-005
74:021-002
74:030-001
74:030-005
74:03F-022
74:03F-035
74:03F-063
74:03F-073
74:03F-080
74:03F-152
74:048-009
74:048-020
74:048-021
74:058-004
74:058-039
74:050-006
74:06A-007
74:060-003
Saline Water-
Freshwater
Interfaces
74:02F-018
74:048-012
Saline Water
Intrusion
74:02F-014
74.-02F-015
74:02F-016
74:02F-018
74:020-026
74:048-012
74:04B-016
Salinity
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
:02F-
:02I-
:03C'
:03C'
:03F'
:03F'
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
:03F
016
002
003
005
006
013
016
021
•022
•030
•035
•039
•042
•045
•058
•063
•067
•090
'-094
-129
-133
'-143
'-152
211
-------
Salinity
(cont.)
74:03F-156
74:03F-168
74:04B-006
74:048-008
74:04B-009
74:048-010
74:04B-011
74:04B-018
74:048-020
74:043-021
74:058-004
74:058-039
74:050-006
74:05G-001
74:050-003
74:06A-005
74:06A-007
74:060-003
74:080-003
Salts
74:02C-001
74:02F-015
74:021-002
74:03F-129
74:03F-143
74:058-039
74:05C-006
Salt Tolerance
74:030003
74:03F-133
74-.03F-156
Sampling
74:02J-004
74:02J-005
74:05A-001
74:05C-001
74:05C-004
74:07B-004
74:078-005
74:078-007
Sands
74:02J-004
Sanitary Engineer-
ing
74:050-004
Saturated Flow
74:020-005
74:020-008
74:020-016
74:058-031
Saturated Soils
74:020-038
Saturation
74:020-038
Scheduling
74:03F-001
74:03F-109
74:03F-115
74:03F-158
74:03F-182
74:060-002
Seed Treatment
74:03F-163
Seeds
Scour
74:040-005
Scaling
74:050002
Seasonal
74:03F-001
74:06A-001
Sedimentation
74:02J-001
74:02J-002
74:02J-005
74:02J-010
74:04A-007
74:058-030
Sedimentation Rates
74:02J-001
Sediment Control
74:02J-001
74:02J-002
74-.02J-010
74:040-001
Sediment Discharge
74:02J-004
74:02J-010
Sediment Load
74:02J-004
74:02J-005
Sediments
74:05A-002
74:058-002
74:058-011
74:058-028
74:058-048
74:058-049
74:058-051
74:050001
74:06A-010
74:078-004
74:078-007
Sediment Transport
74:02J-002
74:02J-003
74:02J-007
Sediment Yield
74:02J-001
74:02J-003
74:02J-005
74:02J-007
74:02J-008
74:02J-009
74:02J-010
74:058-014
74:06A-010
74:03F-089
74:03F-163
74:03F-164
Seepage
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
02G-003
02G-004
02G-011
02G-028
038-001
03F-137
03F-151
04A-007
05A-003
058-004
058-031
05B-033
05D-003
08A-006
088-001
080-001
Seepage Control
74:03F-151
74:050-001
74:08A-006
Septic Tanks
74:02G-046
74:050-001
Sewage
74:030002
74:058-042
Sewage Disposal
74:030002
74:05D-001
Sewage Effluents
74:030002
74:058-042
Sewage Treatment
74:050-002
Shales
74:02K-001
Sheet Erosion
74:02J-007
Silica
74:02K-001
Simulated Rain-
fall
74:02J-009
74:03F-113
Simulation Analy-
sis
74:02A-002
74:02E-001
74:02F-008
212
-------
Simulation Analysis
(cont.)
74:02F-011
74:02F-012
74:02F-017
74:02G-031
74:02G-048
74:02J-002
74:03F-113
74:03F-114
74:03F-139
74:04A-010
74:04A-002
74:048-002
74:048-013
74:058-005
74:06A-002
74:06A-008
Social Needs
74:06A-009
Size
74:03C-001
Slope Projection
74:02J-009
Slope Stabilization
74:02J-009
Slope Stability
74:02J-006
Slopes
74:02G-004
74:02J-003
Sludge
74:088-004
Small Watersheds
74:02A-001
74:058-009
Snow
74:02G-034
Snow Cover
74:02G-034
Snowfall
74:02G-034
Snowmelt
74:02C-002
74:02F-012
74:05B-028
74:056-043
Snowpacks
74:020-002
74:02F-012
Social Aspects
74:058-040
Social Impact
74:06A-009
74:06E-001
Sodium
74:02K-001
74:03F-131
Soil
74:02G-036
74:03F-135
74:03F-157
Soil Aggregates
74:03F-162
74:03F-164
74:080-006
Soil Chemical Prop-
erties
74:03F-131
Soil Chemistry
74:02G-033
74:02G-043
74:02G-045
74:03F-131
74:03F-132
74:048-019
74:058-023
74:058-026
74:058-027
74:058-029
Soil Conservation
74:02J-006
74:02J-009
74:058-014
Soil Disposal Fields
74:02G-046
74:058-025
Soil Erosion
74:02J-003
74:02J-006
74:03F-024
74:040-002
74:058-008
Soil Gases
74:02G-008
Soil Horizons
74:02G-041
74:02G-050
Soil Investigations
74:020-003
74:02G-020
74:02G-029
74:02G-032
74:02G-033
74:020-036
74:020-041
74:02G-045
74:020-046
74:020-047
74:02G-048
Soil Investiga-
tions
74:02G-049
74:020-050
74:03F-116
74:03F-141
74:03F-157
74:05A-003
74:078-005
74:078-006
Soil Management
74:020-020
74:02J-006
74:03F-096
74:058-010
Soil Mechanics
74:020-003
Soil Microorgan-
isms
74:058-017
Soil Moisture
74.:02D-002
74:02G-001
74:020-003
74:020-007
74:020-009
74:020-017
74:03F-002
74:03F-005
74:03F-042
74:03F-048
74:03F-049
74:03F-109
74:03F-116
74:03F-171
74:048-006
74:058-023
74:060-001
74:078-002
Soil Physical
Properties
74:020-012
74:020-020
Soil Physics
74:020-027
74:03F-005
74:048-017
Soil Pressure
74:020-003
Soil Profiles
74:020-037
74:020-041
74:020-043
74:020-045
74:020-047
74:048-019
74:080-005
Soil Properties
74:020-003
213
-------
Soil Properties
(cont.)
74:02G-023
74:02G-024
74:020-027
74:02G-035
74:02G-046
74:020-050
74:03F-096
74:03F-111
74:03P-116
74:03F-131
74:03F-132
74:048-014
74:046-017
74:04B-018
74:05B-036
74:058-050
74:076-005
74:08D-004
74:080-005
Soils
74:02G-018
74:030001
74:04B-004
74:05A-002
74:058-007
74:056-012
74:056-017
74:058-036
74:058-037
Soil Salinity
74:03F-098
74:048-018
Soil Stability
74:02G-003
Soil Structure
74:02G-046
Soil Surveys
74:078-005
Soil Temperature
74:02F-006
74:03F-027
74:03F-077
74:078-001
Soil Tests
74:02G-018
74:02G-032
74:02G-033
74:02G-035
74:03F-123
74:03F-131
74:03F-176
74:048-018
74:078-005
Soil Texture
74:02G-033
74:058-023
Soil Treatment
74:02G-020
Soil Water
74:02C-001
74:020-003
74:020-018
74:02G-023
74:020-029
74:020-031
74:020-032
74:020-034
74:020-035
74:020-040
74:03F-004
74:03F-072
74:03F-105
74:03F-112
74:03F-127
74:03F-128
74:03F-132
74:03F-136
74:03F-139
74:03F-141
74:03F-145
74:03F-158
74-.03F-161
74:03F-163
74:03F-164
74:03F-167
74:03F-173
74:03F-177
74:03F-182
74:078-006
74:08D-004
Soil Water
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
74:
Movement
02D-002
02F-012
02F-017
020-003
02G-005
02G-006
020-008
020-009
020-010
02G-011
020-017
02G-018
020-019
020-020
02G-023
02G-025
02G-026
02G-027
020-028
02G-029
02G-031
020-032
02G-034
02G-035
020-040
02G-044
02G-046
020-049
03F-004
03F-005
03F-006
Soil Water Move-
ment
74:03F-021
74:03F-052
74:03F-054
74:03F-067
74:03F-078
74:03F-085.
74:03F-095
74:03F-111
74:03F-112
74:03F-116
74:03F-127
74:03F-128
74:03F-135
74:03F-136
74:03F-137
74:03F-139
74:03F-141
74:03F-167
74:048-013
74:048-015
74:048-016
74:048-017
74:05A-003
74:058-011
74:058-018
74:058-019
74:058-020
74:058-021
74:058-022
74:058-024
74:058-034
74:058-053
74:088-003
74:080-004
Soil-Water-Plant
Relationships
74:020-004
74:020-025
74:03F-054
74:03F-158
74:03F-161
74:03F-163
74:03F-164
74:03F-171
74:048-015
Soil Water Poten-
tial
74:03F-171
Solar Radiation
74:03F-173
Solubility
74:058-026
Solutes
74:03F-126
74:058-022
Solvent Extrac-
tions
74:05A-002
214
-------
Sorghum
74:03F-123
Sorption
74:02G-013
74:03F-124
74:058-025
74:05B-026
South Dakota
74:058-028
Soybeans
74:03F-122
74:03F-145
74:03F-146
74:03F-158
74:03F-183
74:058-044
Specific Yield
74:02F-011
Sprinkler
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
74
Irrigation
:03F-010
:03F-019
:03F-035
:03F-039
:03F-042
:03F-055
:03F-065
:03F-070
:03F-073
:03F-093
:03F-096
:03F-103
:03F-120
:03F-150
:03F-153
:03F-172
:04B-010
:04B-011
:04B-019
:05D-003
:07B-003
:08A-004
:08A-006
:08A-007
:08A-008
Stage-Discharge Re-
lations
74.-04A-004
Standards
74:058-001
Statistical Methods
74:02E-002
74:02E-004
74:02J-005
74:048-005
74:070-001
Statistical Models
74:02A-002
74:02E-001
74:02F-003
74:058-016
Statistical Models
(cont.)
74:070-003
Statistics
74:02E-004
74:03F-105
74:070-001
Stochastic Processes
74:02A-002
74:02A-003
74:02F-003
74:04A-002
74:048-005
Storage
74:02A-003
Storage Capacity
74:02F-009
Storage Coefficient
74:02F-011
74:02F-020
Stream Erosion
74:02J-008
Streamflow
74:02A-003
74:02E-002
74:02E-004
74:04A-002
Streamflow Forecasting
74:02E-001
- 74:02E-004
Streams
74:02E-004
74:02J-004
74:058-001
74:058-047
Stress
74:020-036
74:03F-099
74:03F-157
Stress Analysis
74:03F-099
Strip Cropping
74:03F-035
Strontium
74:02K-001
74:058-047
Subsurface Drainage
74:020-014
74:03F-004
74:04A-001
74:050-001
Subsurface Drains
74:088-003
74:08C-003
Subsurface Irri-
gation
74:020-019
74:02G-036
74:03F-005
74:03F-006
74:03F-019
74:03F-021
74:03F-022
74:03F-034
74:03F-042
74:03F-047
74:03F-065
74:03F-087
74:03F-095
74:03F-097
74:03F-111
74:03F-120
74:03F-157
74:03F-169
74:048-010
74:088-003
Subsurface Run-
off
74:02F-012
Subtropic
74:03F-077
Sugar Beets
74:03F-098
74:03F-103
74:03F-160
Sugarcane
74.-03F-032
74:03F-047
74:03F-076
Sulfates
74:02K-001
74:058-036
Sulfur
74:058-036
74:058-051
Sulfur Bacteria
74:03F-025
Supplemental Ir-
rigation
74:03F-165
Surface Drainage
74:03F-004
Surface-Ground-
water Rela-
tionships
74:02F-001
74:02F-003
74:04A-004
74:046-005
74:058-013
215
-------
Surface Irrigation
74:03F-063
74:03F-073
74:03F-101
74:03F-162
74:03F-170 .
74:048-009
74:048-011
74:08B-001
74:08D-006
Surface Runoff
74:02J-007
74:040-004
74:058-028
Surface Water
74:02J-007
Surface Waters
74:048-002
74:048-003
74:050001
Surveys
74:03F-082
74:040-001
Suspended Load
74:02J-005
Suspended Solids
74:058-002
74:078-007
Sweet Corn
74:03F-027
74:03F-042
74:03F-065
74:03F-130
74:03F-165
Synthetic Hydrology
74:02A-002
74:02E-002
Systems Analysis
74:02A-001
74:03C-001
74:03F-001
74:03F-002
74:03F-002
74:04A-001
74:04A-002
74-.04A-003
74:048-002
74:048-003
74:048-006
74:058-001
74:058-005
74:06A-003
74:07C-002
74:07C-003
Taxes
Technology
74:050-003
74:06A-006
Temperature
74:02C-002
74:02G-036
74:03F-027
74:03F-108
74:03F-157
74:060-002
74:078-001
Tensiometers
74:02G-010
74:02G-022
74:02G-032
74:020-035
74:03F-055
74:080-003
Tension
74-.02G-010
Terracing
74:058-014
Tertiary Treatment
74:05C-004
74:050-002
Testing Procedures
74:020-018
Texas
74:03F-032
74:03F-063
74:048-009
Thawing
74:02G-017
Theoretical Analysis
74:02G-029
74:02E-003
74:03F-136
74:08A-010
Thermal Properties
74:02G-017
Thermal Stress
74:02G-036
74:03F-157
Thermodynamics
74:02G-013
74:058-026
Thesis Equation
74:02F-020
Tides
74:02A-003
74:048-006
74:050-002
Tile Drainage
74:020-005
74:020-044
74:03F-004
Tile Drainage
(cont.)
74:05A-003
74:058-024
74:058-051
Tile Drains
74:04A-001
74:08C-003
Tiles
Time
74:050-001
74:03F-002
Time Series
Analysis
74:02E-002
74:02F-008
74:058-016
74:070-001
Timing
74:03F-182
Tomatoes
74:03F-040
74:03F-060
74:03F-061
74:03F-079
Topography
74:020-004
74:02J-006
Trace Elements
74:05A-002
Translocation
74:058-006
Transmissivity
74:02F-005
74:02F-020
74:04A-006
Transpiration
74:03F-142
74:03F-143
74:03F-144
74:058-044
Travel Time
74:088-002
Treatment Facil-
ities
74:058-001
Trenches
74:02G-028
74:03F-137
Tritium
74:048-004
Tundra
74:020-017
216
-------
Tunnels
74:048-004
Turbidity
74:030-004
74:03F-149
74:050001
Turbulence
74:02J-004
74:05B-032
Turf Grasses
74:02G-036
74:03F-157
Uniform Flow
74:03F-046
74:03F-147
74:08A-002
Uniformity
74:03F-048
Uniformity Coeffi-
cient
74:03F-046
74:03F-102
Unit Costs
74:040-001
Unit Hydrographs
74:02A-003
United States
74:04A-008
Unsaturated Flow
74:02C-002
74:02F-011
74:02G-009
74:02G-01Q
74:02G-Oll
74:020-015
74:02G-018
74:020-021
74:020-028
74:02G-031
74:03F-127
74:03F-128
74:03F-132
74:03F-137
74:03F-139
74:058-018
74:058-019
74:058-020
74:058-021
74:058-022
74:080-002
Unsteady Flow
74:02F-002
74:02F-005
74:02F-013
74:02G-003
74:02G-031
74:03F-139
Unsteady Flow
(cont.)
74:048-007
74:058-013
Urea
74:03F-140
Vapor Pressure
74:03C-005
74:03F-135
Variability
74:02A-002
74:020-001
Vegetable Crops
74:03F-042
74:03F-156
Vegetation
74:03F-001
74:03F-180
74:03F-181
Vegetation Effects
74:03F-180
74:03F-181
Vine Crops
74:03C-002
Washington
74:04A-001
74:058-005
Waste Disposal
74:058-025
74:05G-002
Wastes
74:04A-011
Waste Water
(Pollution)
74:048-011
74:058-041
74:05C-004
Waste Water Disposal
74:050-001
74:050-003
Waste Water Treatment
74:05C-004
74:050-002
74:06A-005
Water Allocation
(Policy)
74:03F-002
Water Balance
74:020-002
74:02G-039
Water Chemistry
74:02G-013
Water Chemistry
(cont.)
74:02G-027
74:02K-001
74:048-017
74:058-004
74:058-023
74:058-026
74:058-027
74:058-042
Water Conserva-
tion
74:03F-062
74:03F-099
74:03F-101
74:03F-153
74:03F-166
74:050-002
74:06A-009
74:08A-007
Water Consump-
tion (Except
Consumptive
Use)
74:038-001
74:03F-182
Water Conveyance
74:038-001
Water Costs
74:06C-002
Water Delivery
74:048-002
Water Demand
74:03C-001
74:048-005
74:06A-002
74:060-003
Water Distribu-
tion (Applied)
74:04A-003
74:056-001
Water Hammer
74:03F-100
Water Level
Fluctuations
74:02F-001
74:02F-003
74:02F-005
74:02F-011
Water Levels
74:02F-014
74:03F-072
74:04A-003
Water Loss
74:020-002
74:038-001
74:04A-004
217
-------
Water Loss
(cont.)
74:05G-001
Water Management
74:03F-160
74:03F-162
74-.03F-171
74:06A-004
74:06D-003
74:078-008
74:080-006
Water Management
(Applied)
74:02E-001
74:02J-001
74:048-002
74:06A-009
Water Policy
74:03F-062
Water Pollution
74:043-020
74:048-021
74:058-016
74:058-038
74:058-041
74:058-042
74:058-043
74:058-048
74:058-049
74:058-052
74:050-001
74:073-007
74:078-008
Water Pollution
Control
74:05A-001
74:058-035
74:078-008
Water Pollution
Effects
74:05C-001
Water Pollution
Sources
74:058-002
74:058-004
74:058-009
74:058-011
74:058-012
74:058-015
74:058-028
74:058-030
74:058-031
74:058-033
74:058-035
74:058-038
74:058-041
74:058-043
74:050-001
74:050-001
Water Pollution
Treatment
74:050-002
Water Properties
74:058-043
Water Quality
74:02F-014
74:02F-015
74:02F-019
74:02G-026
74:020-042
74:02G-043
74:020-049
74:020-050
74:02J-010
74:030-001
74:03F-063
74:048-009
74:048-016
74:048-020
74:048-021
74:05A-001
74:058-004
74:058-005
74:05B-013
74:058-014
74:058-016
74:058-030
74:058-035
74:058-038
74:058-041
74:058-042
74:058-043
74:058-046
74:058-047
74:058-048
74:058-049
74:058-050
74:058-052
74:050-002
74:05G-001
74:06A-009
74:060-003
74:060-003
74:078-007
74:078-008
74:070-001
Water Quality Control
74:02J-010
74:048-006
74:058-001
74:06A-005
74:078-008
74:070-003
Water Quality Standards
74:06A-005
Water Quantity
74:03F-002
Water Rates
74:030-001
Water Require-
ments
74:03F-009
74:03F-015
74:03F-044
74:03F-099
Water Resources
74:04B-003
74:048-012
74:06A-003
Water Resource
Development
74:02E-001
74:048-001
74:058-005
74:06A-002
Water Reuse
74:050-002
Watershed Manage-
ment
74:02G-034
74:02J-008
74:040-004
74:040-005
74:058-045
74:058-052
74:06A-010
74:060-003
74:06E-001
Watersheds (Ba-
sins)
74:02J-008
74:05A-030
74:058-045
74:06A-010.
74:06E-001
74:078-004
Water Shortage
74:03F-177
Water Spreading
74:02F-001
Water Supply
74:02E-001
74:030-001
74:048-002
74:048-006
74-.06A-002
74:060-003
Water Supply
Development
74:06A-008
Water Table
74:02F-001
74:02F-003
74:02F-005
74:02F-011
74:020-004
74:020-014
218
-------
Water Table
(cont.)
74:02G-038
74:04A-001
74:04B-001
74:048-002
Water Temperature
74:02K-001
Water Transfer
74:02E-001
74:060-003
Water Utilization
74:02F-015
74:03F-002
74:03F-007
74:03F-014
74:03F-015
74:03F-109
74:03F-115
74:043-006
74:05B-005
Water Yield
74:02A-001
74:02C-002
74:02F-011
74:048-001
74:048-005
74:088-002
Wavelength
74:078-002
Wells
74:02F-007
74:048-002
74:058-054
74:08A-010
74:088-005
Well Screen
74:08A-010
Wetting
74:02G-008
74:020-009
74:020-011
74:020-029
74:020-030
74:03F-010
74:03F-072
74:03F-112
74:03F-138
Wheat
74:030003
74:030005
74:03F-002
74:03F-045
74:03F-133
74:03F-156
74:03F-173
74:03F-174
74:03F-175
74:03F-176
74:048-008
Wheatgrasses
74:03F-166
Winds 74:020-001
Withdrawal
74:048-001
74:048-005
Yield Equations
74:03F-002
Zeolites
74:02K-001
Zinc
74:03F-053
74:05A-002
219
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-76-019
3. RECIPIENT'S ACCESSION>NO.
4. TITLE AND SUBTITLE
SELECTED IRRIGATION RETURN FLOW QUALITY ABSTRACTS
1974
5. REPORT DATE
March 1976 ("Issuing Date)
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO
Skogerboe, Gaylord V., Walker, Wynn R., and
Smith. Stephen W.
>. PERFORMING ORGANIZATION NAME AND ADDRESS
Agricultural Engineering Department
Colorado State University
Fort Collins, Colorado 80521
10. PROGRAM ELEMENT NO.
1BB039
NO.
R- 8004 26
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Research and Development
Washington, D.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA-ORD
15. SUPPLEMENTARY NOTES
See also EPA-R2-72-094, PB 214 105; EPA-R2-73-271, PB 222 796; and EPA-660/2-74-049,
PB 235 385.
16. 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 National Irrigation Return Flow 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, and the third annual issue covers calendar years 1972 and 1973. This annual
issue lists publications printed in 1974. This report was submitted in fulfillment
of Grant Number R-800426 under the sponsorship of the Office of Research and
Development, Environmental Protection Agency. (Skogerboe-Colorado State)
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Fertilizers, Irrigation, Irrigated land,
Salinity, Water pollution
Irrigation systems, Irri-
gation water, Nitrates,
Phosphates, Return flow,
Water pollution effects,
Water pollution sources,
Water quality control
2C
8. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS (This Report I
UNCLASSIFIED
21. NO. OF PAGES
228
20. SECURITY CLASS (Thtlpage)
22. PRICE
EPA Form 2220-1 (9-73)
220
U. S. 60VEINMENT HINTINC OFFICE: 1976-657-695/5388 R.glon No. 5-11
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