United States
Environmental Protection
Agency
Roberts Kerr Environmental Research EPA-600 2-79-020
Laboratory January 1979
Ada OK 74820
Research and Development
&EPA
Selected Irrigation
Return Flow
Quality Abstracts
1977
Seventh Annual
Issue
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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 nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1 Environmental Health Effects Research
2 Environmental Protection Technology
3 Ecological Research
4 Environmental Monitoring
5 Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution-sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield. Virginia 22161.
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EPA-600/2-79-020
January 1979
SELECTED IRRIGATION RETURN FLOW
QUALITY ABSTRACTS 1977
Seventh Annual Issue
by
Gaylord V. Skogerboe
Stephen W. Smith
Wynn R. Walker
Sue Eastman
Colorado State University
Fort Collins, Colorado 80523
Grant No. R-800426
Project Officer
Alvin L. Wood
Source Management Branch
Robert S. Kerr Environmental Research Laboratory
Ada, Oklahoma 74820
ROBERT S. KERR ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
ADA, OKLAHOMA 74820
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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. Environmental Protection Agency, nor does mention of trade
names or commercial products constitute endorsement or
recommendation for use.
.11
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FOREWORD
The Environmental Protection Agency was established to
coordinate administration of the major Federal programs designed
to protect the quality of our environment.
An important part of the Agency's effort involves the
search for information about environmental problems, management
techniques and new technologies through which optimum use of the
Nation's land and water resources can be assured and the threat
pollution poses to the welfare of the American people can be
minimized.
EPA's Office of Research and Development conducts this
search through a nationwide network of research facilities.
As one of these facilities, the Robert S. Kerr Environmental
Research Laboratory is responsible for the management of programs
to: (a) investigate the nature, transport, fate and management
of pollutants in groundwater; (b) develop and demonstrate methods
for treating wastewaters with soil and other natural systems;
(c) develop and demonstrate pollution control technologies for
irrigation return flows; (d) develop and demonstrate pollution
control technologies for animal production wastes; (e) develop
and demonstrate technologies to prevent, control or abate pollu-
tion from the petroleum refining the petrochemical industries;
and (f) develop and demonstrate technologies to manage pollution
resulting from combinations of industrial wastewaters or
industrial/municipal wastewaters.
This report contributes to the knowledge essential if the
EPA is to meet the requirements of environmental laws that it
establish and enforce pollution control standards which are
reasonable, cost effective and provide adequate protection for
the American public.
William C. Galegai
Director
Robert S. Kerr Environmental
Research Laboratory
111
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PREFACE
The seventh annual issue of SELECTED IRRIGATION RETURN
FLOW QUALITY ABSTRACTS has been compiled from approximately_100
sources of material covering calendar year 1977. This compila-
tion has attempted to include technological and institutional
articles that would be pertinent to action programs regarding
the control of water quality degradation resulting from irrigated
agriculture.
The state-of-the-art report, "Characteristics and Pollution
Problems of Irrigation Return Flow," prepared by the Utah State
University Foundation, contains a bibliography of articles perti-
nent to Irrigation Return Flow Quality through 1967. The first
annual issue of SELECTED IRRIGATION RETURN FLOW QUALITY ABSTRACTS
listed publications appearing in calendar years 1968 and 1969,
while the second annual issue listed publications appearing in
calendar years of 1970 and 1971, the third annual issue contained
abstracts of articles and reports published during calendar
years 1972 and 1973, and the fourth, fifth, and sixth annual
issues contained abstracts of 1974, 1975, and 1976 publications.
The seventh annual issue contains 731 abstracts of documents
published during calendar year 1977. The abstracts have been
placed into sections according to the category and subgroup
classifications used by the Water Resources Scientific Informa-
tion Center (WRSIC) as published in'the report, "Water Resources
Thesaurus." The abstracts have been forwarded to WRSIC for
inclusion in their bi-monthly publication, "Selected Water
Resources Abstracts."
IV
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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
institutions in the United States, as well as other portions of
the world. Approximately 100 sources of material have been
searched for articles pertinent to the Irrigated Crop Production
research and development program. These articles describe water
quality problems resulting from irrigated agriculture, potential
technological solutions for controlling return flows, recent
research pertinent to return flow investigations, and literature
associated with institional constraints in irrigation return flow
quality control.
The first annual issue of SELECTED IRRIGATION RETURN FLOW
QUALITY ABSTRACTS covered publications printed in 1968 and 1969,
while the second annual issue lists publications printed in 1970
and 1971, the third annual issue covers calendar years 1972 and
1973, and the fourth, fifth, and sixth annual issues cover liter-
ature published in 1974, 1975, and 1976. This annual issue lists
publications printed in 1977. This report was submitted in ful-
fillment of Grant No. R-800426 under the sponsorship of the
Office of Research and Development, U.S. Environmental Protection
Agency.
Key Words: Fertilizers, Irrigated land, Irrigation Systems,
Irrigation water, Nitrates, Phosphates, Return flow, Salinity,
Water pollution effects, Water pollution sources, Water quality
control.
v
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TABLE OF CONTENTS
Foreword . . . ,
Preface . . . ,
Abstract . . .
Acknowledgments
. 111
iv
v
viii
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
XII
XIII
XIV
XV
XVI
XVII
XVIII
XIX
XX
XXI
XXII
WATER CYCLE - Precipitation (Group 02B) ,
WATER CYCLE - Snow, Ice, and Frost (Group 02C). . ,
WATER CYCLE - Evaporation and Transpiration (Group
02D) ,
WATER CYCLE
WATER CYCLE
WATER CYCLE
WATER CYCLE
WATER CYCLE
WATER CYCLE
Streamflow and Runoff (Group 02E) . . ,
Groundwater (Group 02F) ,
Water in Soils (Group 02G) ,
Water and Plants (Group 021) ,
Erosion and Sedimentation (Group 02J) ,
Chemical Processes (Group 02K) . . . ,
WATER CYCLE - Estuaries (Group 02L) .
WATER SUPPLY AUGMENTATION AND CONSERVATION - Saline
Water Conversion (Group 03A)
WATER SUPPLY AUGMENTATION AND CONSERVATION - Water
Yield Improvement (Group 03B) ,
WATER SUPPLY AUGMENTATION AND CONSERVATION - Use of
Water of Impaired Quality (Group 03C)
WATER SUPPLY AUGMENTATION AND CONSERVATION - Con-
servation in Agriculture (Group 03F) .
WATER QUANTITY MANAGEMENT AND CONTROL - Control of
Water on the Surface (Group 04A) ,
WATER QUANTITY MANAGEMENT AND CONTROL - Groundwater
Management (Group 04B) ,
WATER QUANTITY MANAGEMENT AND CONTROL - Watershed
Protection (Group 04D) ,
WATER QUALITY MANAGEMENT AND PROTECTION - Identi-
fication of Pollutants (Group 05A) ,
WATER QUALITY MANAGEMENT AND PROTECTION - Sources
and Fate of Pollution (Group 05B) ,
WATER QUALITY MANAGEMENT AND PROTECTION - Effects of
Pollution (Group 05C)
WATER QUALITY MANAGEMENT AND PROTECTION - Waste
Treatment Processes (Group 05D)
WATER QUALITY MANAGEMENT AND PROTECTION - Ultimate
Disposal of Wastes (Group 05E)
1
2
3
8
11
30
92
99
115
117
118
119
120
122
163
177
183
186
191
213
215
219
VI1
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XXVII WATER QUALITY MANAGEMENT AND PROTECTION - Water
Quality Control (Group 05G)
XXVIII WATER RESOURCES AND PLANNING - Techniques of
Planning (Group 06A)
XXIX WATER RESOURCES PLANNING - Evaluation Process
(Group 06B)
XXX WATER RESOURCES PLANNING - Cost Allocation,
Cost Sharing, Pricing/Repayment (Group 06C) .
XXXI WATER RESOURCES PLANNING - Water Demand (Group 06D)
XXXII WATER RESOURCES PLANNING - Water Law and Institu-
tions (Group 06E)
XXIII RESOURCES DATA - Data Acquisition (Group 07B) . . -
XXV ENGINEERING WORKS - Structures (Group 08A)
XXVI ENGINEERING WORKS - Hydraulics (Group 08B). . . .
XXXIII ENGINEERING WORKS - Hydraulic Machinery (Group 08C)
XXXIV MANPOWER, GRANTS, AND FACILITIES - Research
Facilities (Group 09C)
XXXV AUTHOR INDEX
XXXVI SUBJECT INDEX
220
234
237
238
239
240
245
258
259
265
266
267
285
Vlll
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ACKNOWLEDGMENTS
The excellent cooperation of the reading room staff at the
Engineering Research Center and the library staff at Colorado
State University has been very important in accomplishing the
work reported herein.
The efforts of Ms. Sue Eastman, Ms. Mary Lindburg, and
Ms. Melanee Lowdermilk 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 scope of this literature abstracting effort has been
delineated jointly by the senior author and project officer,
Mr. Alvin L. Wood, Source Management Branch, Robert S. Kerr
Environmental Research Laboratory, Environmental Protection
Agency, Ada, Oklahoma. The cooperative efforts of the Project
Officer in meeting with project personnel and reviewing the
abstracting process have been very helpful and are sincerely
appreciated.
IX
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SECTION I
WATER CYCLE
PRECIPITATION (GROUP 02B)
77:02B-001
EFFECTS OF SOIL, COVER CROP, AND NUTRIENT SOURCE ON MOVEMENT OF SOIL, WATER, AND
NITROGEN UNDER SIMULATED RAIN-SLOPE CONDITIONS,
Hoyt, G.D., McLean, E.O., Reddy, G.Y., and Logan, T.J.
Ohio Agricultural Research and Development Center, Wooster, Ohio.
Journal of Environmental Quality, Vol. 6, No. 3, p 285-290, July-September, 1977.
2 fig, 7 tab, 22 ref.
Descriptors: *Soil erosion, *Runoff, *Simulated rainfall, *Model studies, *0hio,
Fertilizers, Soils, Nitrogen, Phosphorus, Potassium, Farm wastes, Crops, Slopes,
Ureas, Rainfall intensity, Time, Leachate, Erosion, Soil contamination.
Nitrogen, P, and K as manure, chemical fertilizers + straw, or chemical fertilizers
alone were added to microplots of soils, which were then either cropped to wheat
or left bare, and finally subjected to simulated rainfall. The N, P, and K were
each applied at 224 kg/ha in the forms of: (1) N- and P-enriched cow manure (7.35
metric tons/ha, dry weight); (2) urea, triple-superphosphate (TSP) , and KC1 + straw
at the same weight of dry matter as the manure; and (3) fertilizers alone. A 5-day
rainfall sequence was imposed with varying intensities, durations, and soil slopes.
The movement of N generally increased as the quantities of solids, runoff, and
leachate increased. Where discrepancies occurred, they could usually be explained
by differences in structure, crusting of the soils, or clogging of their pores by
manure, or by effects of straw on soil permeability to water or on increased micro-
bial activity. In general, almost all the mineral N moving in the leachate, and
about half of.that moving in runoff, was in N03 form.
77:02B-002
COMPUTATION OF INFILTRATION FOR UNSTEADY UNINTERRUPTED HIGH RAINFALL,
Morel-Seytoux, H.J., Pick, T.A., and Jonch-Clausen, T.
Colorado State University, Engineering Research Center, Fort Collins, Colorado.
Journal of Hydrology, Vol. 35, No. 3/4, p 221-234, November 1977. 7 fig, 1 tab,
21 ref.
Descriptors: *Infiltration, *Rainfall, *Model studies. Mathematical models,
Precipitation (atmospheric), Ponding, Runoff, Equations, Formulas, Hydrographs,
Hydraulic conductivity, Precipitation intensity, Precipitation excess, Soils,
Soil water movement, Percolation, Permeability, Soil properties, Rainfall patterns.
The use of previously proposed formulas for rainfall infiltration demonstrated
the sensitivity of the response hydrographs to the rainfall pattern. For steady
rainfall, the proposed formulas of ponding time and of infiltration rate after
ponding were verified by comparison with experimental data. For unsteady rain-
fall, inspection of the formulas indicated that they may be in serious error for
low-intensity rains of long duration.
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SECTION II
WATER CYCLE
SNOW, ICE, AND FROST (GROUP O2C)
77:02C-001
WATER AND ICE POTENTIALS IN FROZEN SOILS,
Groenevelt, P.H., and Kay, B.D.
Guelph University, Department of Land Resource Science, Ontario, Canada.
Water Resources Research, Vol. 13, No. 2, p 445-449, April 1977. 3 fig, 19 ref.
Descriptors: *Frozen soils, *Moisture content, *Ice, *Model studies, Mathematical
models, Porous media, Soils, Soil water, Voids, Hysteresis, Temperature, Freezing,
Frozen ground, Frost, Frost action.
The envelope pressure potentials of the liquid water and ice in a frozen soil were
identified. The envelope pressure potential of liquid water is a generalization
of the definition of the envelope pressure potential (overburden potential) of the
water in an unfrozen swelling soil. In order to express the envelope pressure
potentials in terms of volume ratios, use was made of the void ratio, the moisture
ratio equivalent, and the ice ratio equivalent. A new development was initiated
by the formulation and derivation of the frost potential of both the liquid water
and the ice. These frost potentials were expressed in terms of the ice ratio,
the moisture ratio, the ice ratio equivalent, and the moisture ratio equivalent.
The relations between these variables are intrinsic properties of the porous
medium which have to be determined experimentally.
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SECTION III
WATER CYCLE
EVAPORATION AND TRANSPIRATION (GROUP 02D)
77:020-001
DETERMINATION OF REGIONAL EVAPOTRANSPIRATION FROM UPPER AIR METEOROLOGICAL DATA,
Mawdsley, J.A., and Brutsaert, W.
Cornell University, School of Civil and Environmental Engineering, Ithaca, New York.
Water Resources Research, Vol. 13, No. 3, p 539-548, June 1977. 6 fig, 7 tab,
27 ref, 1 append.
Descriptors: *Evapotranspiration, *Estimating, *Nebraska, *Iowa, Model studies,
Mathematical models, Atmosphere, Weather data, Meteorological data, Hydrologic
aspects, Boundary processes, Boundary layers, Evaporation, Equations, Data pro-
cessing, Analysis, Theoretical analysis, Analytical techniques, Watersheds (basins),
Correlation analysis, Monthly.
A procedure, recently proposed by the authors to calculate actual evapotranspira-
tion on the basis of parameterization of the atmospheric boundary layer, was ap-
plied for the period April through November 1969-1972 with upper air ("rawin-
sonde") meteorological data from Omaha, Nebraska. The accuracy of the 1-day, 3-
day, weekly, and monthly evapotranspiration totals was assessed by comparing them
to evapotranspiration data estimated by a suitable adjustment of potential evapo-
transpiration from a nearby catchment in the Treynor basins. Several alternative
methods for determining the height of the boundary layer and the wind speed at the
top of the boundary layer were used: as a result, seven variations of the basic
procedure were tested. The similarity functions for water vapor D were found to
be smaller than the corresponding functions for sensible heat C, not equal as was
assumed previously. Difficulties were encountered, since published upper air
humidity data were in error: nevertheless, the method was successful on a monthly
basis with a correlation coefficient of the order of 0.83, but far less successful
on a daily basis. The recommended version of the method used the height of the
temperature inversion as an estimate of the boundary layer height and the mea-
sured wind as the estimate of the boundary layer height and the measured wind as
the estimate of the wind speed at the top of the boundary layer.
77:02D-002
EFFECT OF INCREASING FOLIAGE REFLECTANCE ON THE C02 UPTAKE AND TRANSPIRATION RE-
SISTANCE OF A GRAIN SORGHUM CROP,
Moreshet, S., Stanhill, G., and Fuchs, M.
Volcani Institute of Agricultural Research, Division of Agricultural Meteorology,
Bet-Dagan (Israel).
Agronomy Journal, Vol. 69, p 246-250, March-April, 1977. 6 fig, 3 tab, 7 ref.
Descriptors: *Reflectance, *Leaves, *Photosynthesis, *Transpiration control,
*Grain sorghum, Solar radiation, Dry farming, Crop response, Crop production,
Spectrophotometry, On-site tests.
Two years of field studies of labeled C02 uptake rates on kaolin-sprayed and un-
sprayed sorghum leaves indicated the coating caused a 23% decrease in net photo-
synthesis similar to the 26% reduction of solar radiation absorption detected
with a spectrophotometer after spraying. Measurements were made during the rain-
less summers of 1973 and 1974 on an unirrigated sorghum crop (.Sorghum bicolor
L. Moench 'Hazera 726') in the Lakhish area of Israel. Grain yield increases
had occurred after whitening of the crop canopy. Decreased photosynthesis per-
sisted for several weeks and was greater 6 weeks after the last kaolin appli-
cation. Most leaves had a slightly increased leaf resistance as well as reduced
C02 uptake; both effects were accentuated by high insulation. Enhanced sene-
scence of the kaolin-coated leaves was confirmed by measurements of the dynamics
of light-dependent C02 uptake of leaves of different ages using neutral filters
and independent measurements of green leaf area. However, field measurements
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with a diffusion porometer indicated only slight reductions in the leaf surface
diffusion resistance of coated leaves. A possible explanation is presented to
reconcile the decrease in photosynthesis with the observed grain yield increase
of treated sorghum.
77:02D-003
ASSESSMENT OF WATER LOSS PATTERNS WITH MICROLYSIMETERS,
Rogowski, A.S., and Jacoby, E.L., Jr.
Agricultural Research Service, Northeast Watershed Research Center,- University
Park, Pennsylvania.
Agronomy Journal, Vol. 69, No. 3, p 419-424, May-June, 1977. 5 fig, 3 tab, 4 ref.
Descriptors: -*Evapotranspiration, *Lysimeters, *Soil water, *Water loss, Soil
water movement, Measurement, On-site tests, Laboratory tests, Nuclear moisture
meters, Model studies.
In order to develop a practical method of evaluating evapotranspiration (ET) in the
field, portable cylindrical grass-growing lysimeters were constructed and tested
on a 58-ha watershed. A laboratory check indicated there was no loss of flow con-
tinuity with periodic lysimeter removal at high soil water levels. A field check
proved feasibility for field use and indicated no significant differences in ET
between different segments of a small study area. The watershed study also in-
cluded gamma-probe measurements and ET predictions with a Blackland ET model. A
number of strategically placed microlysimeters may estimate an ET component over
a larger area as long as the predominant rooting depth is about 30 cm. Only very
stony and wooded sites presented ET estimation problems for any of the three
methods.
77:020-004
EVAPORATION AND SALT MOVEMENT IN SOILS IN THE PRESENCE OF WATER TABLE,
Hassan, F.A., and Ghaibeh, A. Sh.
Alexandria University, Department of Soils and Water Science, Alexandria, (Egypt).
Soil Science Society of America Journal, Vol. 41, No. 3, p 470-478, May-June,
1977. 8 fig, 3 tab, 6 ref.
Descriptors: *Soil moisture, *Evaporation, *Salts, Soil water, Soil water move-
ment, Model studies, Mathematical models, Laboratory tests, Loam, Clays, Foreign
countries, Soils, Foreign research, Profiles, Soil profiles, Moisture tension,
Hydraulic conductivity, Tensioraeters, Soil physics, Soil science.
Evaporation from homogeneous and stratified columns, in the presence of shallow
water table, at steady-state, was examined. Soils from Syria and Egypt were used.
The hydraulic conductivity-moisture tension curves of the soils were determined
and were fitted to smooth curves represented by Gardner's empirical formula.
Solutions obtained by Gardner for the steady flow equations were modified for the
boundary conditions of the top and bottom layers, and then the solutions were
reduced to a dimensionless form with two variables, the relative flux density
and the relative tension at the interface. The resulting equations were used to
calculate the evaporation rates. Salt profiles near the surface, at different
evaporation rates, also were studied. In case of homogeneous soil columns,
the calculated values gave close estimates of the measured evaporation rates.
However, the ratio of "the calculated to measured rates was 1.3 to 1.6 for
stratified columns. The salt profiles in the top dry layer indicated the
polyphasic nature of water movement in the top zone. The observed increase
in the dispersion coefficient with the solution velocity was more pronounced
in soils of wider range of pore size.
77:020-005
EVALUATION OF AN EVAPOTRANSPIRATION MODEL FOR CORN,
Rosenthal, W.D., Kanemasu, E.T., Raney, R.J., and Stone, L.R.
Kansas State University, Department of Agronomy, Manhattan, Kansas.
Agronomy Journal, Vol. 69, No. 3, p 461-464, May-June, 1977. 4 fig, 1 tab, 16 ref.
Descriptors: *Evapotranspiration, *Model studies, *Corn (field), *Kansas, *Soil
water, On-site tests, Computer models, Input-output analysis, Irrigation practices,
Meteorological data, Withdrawal, Soil profiles, Crop response.
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An empirical evapotranspiration model was developed and tested for corn (Zea
mays (L.) cv. Dekalb XL72A) grown on two sites in Kansas; soil water estimates
determined by the computerized model were compared with neutron attenuation
estimates. Required daily inputs for the model include leaf area index, solar
radiation, effective precipitation and maximum and minimum air temperatures;
outputs include transpiration, evaporation, advective contribution and soil
water content. Model estimates were within 6% of neutron attenuation estimates
during the growing season. The greatest water use efficiency and yield was
achieved with an irrigation treatment involving 40% depletion of the maximum
available water in the 150-cm profile. The model used has potential in scheduling
irrigation on corn since required meteorological inputs can be routinely ob-
tained at the field site. Leaf area index must be measured, estimated from remote
sensing techniques, or simulated from leaf growth models.
77:020-006
SURFACE ROUGHNESS OF CROPS AND POTENTIAL EVAPOTRANSPIRATION,
Slabbers, P.J.
International Institute for Land Reclamation and Improvement, Wageningen (Nether-
lands) .
Journal of Hydrology, Vol. 34, No. 1/2, p 181-191, July 1977. 5 fig, 4 tab, 25 ref.
Descriptors: *Evapotranspiration, *Roughness coefficient, *Crops, Winds, Grasses,
Climatology, Arid climates, Wind velocity. Foreign countries, Foreign research.
A roughness function for grass was derived by Rijtema for climatological condi-
tions in The Netherlands. The function depends on wind speed and crop length and
was used to determine the aerodynamics resistance of grass when calculating po-
tential evapotranspiration. An analysis was made of data collected in southern
Iran and of data that had been published for northern Iran, Lebanon, and Tunisia
to determine whether the function also could be used in calculating crop water
requirements under semi-arid and arid conditions. Except for some deviating data
for which explanations were presented, agreement was obtained for all crops tested
against the original relationship for grass. The importance of taking crop rough-
ness into account in the combination equation, especially for relatively tall crops,
was stressed.
77:020-007
WATER REQUIREMENTS FOR MESQUITE (PROSOPIS JULIFLORA),
Tromble, J.M.
Agricultural Research Service, Southwest Watershed Research Center, Tucson, Arizona.
Journal of Hydrology, Vol. 34, No. 1/2, p 171-179, July 1977. 4 fig, 2 tab, 11 ref.
Descriptors: *Water requirements, *Mesquite, *Evapotranspiration, Runoff, Indexing,
Water users, Water table, Vegetation, Water resources, Water utilization.
Evapotranspiration (ET) determined by different investigators, compared with values
determined by the White and Troxell methods, showed that their values provided rea-
sonable estimates and that utilizing diurnal water table fluctuations furnished a
method of computing ET with less than 100% vegetation density. Average daily max-
imum ET rates for June were calculated, and ratios were compared with values from
other independent studies. Since ET rates, determined by White and Troxell meth-
ods, indicated plausible values of water use when compared to other independent
studies, the ET rates could be considered index values useful as guidelines for
water abstracted by mesquite. Water table elevation measurements on a shallow
perched aquifer under a mesquite thicket were used to calculate ET for time periods
when the water table elevation varied diurnally- Average daily maximum ET values
for June, when annual ET rates were highest, for the three years as predicted by
the daily rate, White and Troxell methods were 1, 61, 10.10 and 12.17 mm, respec-
tively -
77:020-008
SAP STREAM VELOCITY AS AN INDICATOR OF THE TRANSPIRATIONAL PROCESS,
Balek, J., and Pavlik, 0.
Ceskoslovenska Akademie Ved, Institute of Hydrodynamics, Prague.
Journal of Hydrology, Vol. 34, No. 1/2, p 193-200, July 1977. 4 fig, 6 ref.
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Descriptors: *Transpiration, *Meteorological data, *Temperature, Water circu-
lation, Radiation, Pressure, Rainfall, Heat flow, Foreign countries, Foreign
research.
Continuous long-term measurements of the spruce sap stream velocity and meteoro-
logical phenomena observed in the Sumava region, Czechoslovakia, indicated two
different relationships between sap stream velocity as a dependent variable and
meteorological factors as independent variables. For mean daily temperatures
above 6 C, the net radiation was found to be the most decisive factor; while for
the temperatures below 6 C, the duration of rainfall during each particular day
was found to be the most significant. Comparative results for the popular tree
were provided. The results served as a transpiration variability indicator for
the water balance circulations.
77:02D-009
MODELING SOIL WATER MOVEMENT INTO PLANT ROOTS,
Slack, D.C., Haan, C.T., and Wells, L.G.
Minnesota University, Department of Agricultural Engineering, St. Paul, Minnesota.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 5,
p 919-927, 933, September-October 1977. 7 fig, 1 tab, 48 ref.
Descriptors: *Soil water movement, *Soil-water-plant relationships, *Evapo-
transpiration, *Corn (field), Root systems, Leaves, Plant physiology, Labora-
tory tests, Model studies. Mathematical models, Soil water, Soil properties,
Hydraulic conductivity, Evaporation, Agriculture.
A mathematical model was developed which describes uptake of water by plant roots
as a function of leaf and soil water potentials. The model was used to estimate
transpiration from corn grown in a controlled environment under soil drying con-
ditions. The model predicted daily transpiration quite well for the period
modeled.
77:020-010
IMPROVING WATER USE IN SPRINKLING FOR BLOOM DELAY,
Barfield, B.J., White, G.M., Bridges, T.C., and Chaplin, C.
Agriculture Engineering Department, Horticulture Department, University of Ken-
tucky, Lexington, Kentucky.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 688-691, 696, August 20, 1977. 5 fig, 8 ref, 1 equ.
Descriptors: Sprinkler irrigation, Cooling, Peaches, Fruit crops, Evaporation,
Mist, Transpiration, Frost protection.
Bud development was delayed on Redhaven peach trees in 1975 by using evaporative
cooling from sprinkler irrigation when bud temperatures exceeded 4.4 C. 104 cm
of water were applied. Analysis was made of the potential reduction in water use
and cooling that would have been obtained if sprinkling had been initiated at bud
temperatures ranging from 4.4 to 9 C whenever cooling potential existed. Cooling
potential was measured by the difference between dry bulb temperature and wet bulb
temperature. The optimum set points for initiating sprinkling were found to be a
dry bud temperature of 6.7 C and a cooling potential of 2.0 C,
77:020-011
A SIMPLIFIED MODEL OF CORN GROWTH UNDER MOISTURE STRESS,
Childs, S.W., Gilley, J.R., and Splinter, W.E.
Agricultural Engineering Department, University of Nebraska, Lincoln, Nebraska.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 858-865, October 20, 1977. 7 fig, 3 tab, 21 ref, 15 equ.
Descriptors: Mathematical models, Soil moisture, Corn, Transpiration, Soil-plant-
water relationships, Evaporation, Plant growth, Crop production, Nebraska, Water
conservation, Hydraulic conductivity.
A mathematical model was developed to simulate the environmental and physiological
processes involved in the growth of corn. Grain yields were accurately predicted
even where inadequate irrigation caused decreased yield. Some predictions of crop
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growth patterns indicated that all of the dynamics of crop growth are not yet
modeled in sufficient detail. However, the accuracy of growth trends in general
indicate that the model has considerable predictive power.
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SECTION IV
WATER CYCLE
STREAMFLOW AND RUNOFF (GROUP O2E)
77:02E-001
PRINCIPLES OF GRAPHICAL GRADUALLY VARIED FLOW MODEL,
Kouwen, N., Harrington, R.A., and Solomon, S.I.
Waterloo University.- Department of Civil Engineering, Ontario, Canada.
Journal of the Hydraulics Division, American Society of Civil Engineers,
Vol. 103, No. HY5, Proceedings Paper 12939, p 531-541, May 1977. 7 fig, 5 ref,
2 append.
Descriptors: *Backwater, *Model studies, *Flow, *Graphical analysis, Computers,
Gradually varied flow, Graphical methods, Hydraulics, Open channel flow, Flow
profiles, Equations, Rivers.
Any gradually varied flow computation requires the solution of the energy and
continuity equations. To this end, many techniques are available. For prismatic
channels, the Direct Step Method gives a result without requiring iteration. How-
ever, for nonprismatic channels, it is necessary to resort to some variation of
the Standard Step Method, thereby requiring some iterative procedure. A graphical
solution, using a simple program to construct a set of curves, can eliminate iter-
ation as well as retain flexibility with regard to flow variations along the
reach. To accomplish this, a graphical solution of the energy equation was pre-
sented which uses hydraulic transform graphs for river cross sections along a
reach.
77:02E-002
EVALUATION OF THE COMPONENTS OF THE USDAHL-74 MODEL OF WATERSHED HYDROLOGY,
Hanson, C.L.
United States Department of Agriculture, Agricultural Research Service, Department
of Agricultural Engineering, Boise, Idaho.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-8.
7 fig, 4 tab, 8 ref.
Descriptors: Model studies, Hydrology, Simulation analysis, Soil water, Runoff,
Idaho, Computer programs.
The USDAHL-74 revised model of watershed hydrology was evaluated on an 83-ha
arid rangeland watershed in southwest Idaho. The model simulated soil water
adequately, except during periods in late summer and fall. The model did not
adequately simulate runoff.
77:02E-003
AGRICULTURE RUNOFF MANAGEMENT (ARM) MODELVERSION II. REFINEMENT AND TESTING,
Donigian, A.S., Jr., Beyerlein, D.C., Davis, H.H., Jr., and Crawford, N.H.
Hydrocomp, Incorporated, Palo Alto, California 94304.
Publication No. EPA-600/3-77-098, August 1977. 294 p, 108 fig, 17 tab, 3 append.
Descriptors: Watersheds, Georgia, Michigan, Hydrology, Pesticides, Sediments,
Nutrients, Runoff, Water quality, Model studies.
The Agricultural Runoff Management (ARM) Model has been refined and tested on small
agricultural watersheds in Georgia and Michigan. The ARM Model simulates the hy-
drology sediment production, pesticide, and nutrient processes on the land surface
and in the soil profile that determine the quantity and quality of agriculture
runoff. This report discusses the research and model refinements related to soil
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moisture and temperature simulation, pesticide degradations, nutrient transfor-
mations and plant nutrient uptake. The goal is to evaluate and improve the
pesticide and nutrient simulation capabilities of the ARM Model. However, the
runoff and sediment modeling is also analyzed since these are the critical tran-
sport mechanisms of agricultural chemicals.
77:02E-004
RUNOFF FREQUENCY FROM SMALL STORMS AND IMPLICATIONS FOR WATER QUALITY,
Lewis, R.B., Hauser, V.L., Menzel, R.G., and Ross, J.D.
Agricultural Research Service, Water Quality Management Laboratory, Durant,
Oklahoma.
Transactions of the American Society of Agricultural Engineers,'Vol. 20, No. 4,
p 661-665, July-August, 1977. 8 fig, 4 tab, 10 ref.
Descriptors: *Runoff, *Nebraska, *Water quality, *Agricultural chemicals, On-
site investigations, Watersheds (basins), Agricultural watersheds, Agricultural
runoff. Chemicals, Farm management, Contour farming, Crops, Field crops, Storms,
Storm runoff, Precipitation (atmosphere), Pollutants, Water pollution, Water
pollution control.
The concentration of chemicals in surface runoff water is often an important
consideration. Water soluble chemicals which are applied to the surface of plants
or soil may appear in highest concentration in runoff from small storms. There-
fore, some aspects of water quality management require quite different hydrologic
information than has been required to solve problems considered in the past. The
study of small storms in the central Great Plains near Hastings, Nebraska, re-
vealed much about small storms and their relation to water quality- Compared
with straight row cultivation, contouring of corn substantially decreased the
number of runoff events resulting from small storms, and thus substantially de-
creased the probability of pollution from surface applied chemicals. The data
showed that wheat on contour produced about 1/3 less annual runoff than wheat
grown with straight row tillage; however, no difference was found between contour
and straight row wheat in the number of runoff events resulting from small storms.
During the months when it is desirable to top-dress nitrogen fertilizer on winter
wheat, there is little or no threat of pollution to surface waters. Few runoff
events were produced by small storms falling on meadow or pasture; therefore,
chemicals may safely be applied to them. During June, the high rainfall month,
there were 5 times more small storms producing no runoff than storms which did
on all cultivated crops except corn with straight row tillage. Thus, if chemi-
cals are applied only when the soil surface is relatively dry, the probability
of surface-water pollution would be small.
77:02E-005
MANNING N AND THE OVERLAND FLOW EQUATION,
Ree, W.O., Wimberly, F.L., and Crow, F.R.
Agricultural Research Service, Stillwater, Oklahoma.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 1,
p 89-95, January-February, 1977. 7 fig, 5 tab, 9 ref.
Descriptors: *Mannings equation, *Watersheds (basins), *Overland flow, *Model
studies, Laboratory tests, Small watersheds, Hydrograph analysis. Grassed water-
ways, Range grasses, Flow, Runoff, Vegetation, Channel flow, Hydraulics, Hydrology.
Manning n values for the overland flow surfaces of a grassed watershed were de-
rived by hydrograph analysis and by using average watershed slope and overland
flow length values determined by geomorphic methods. These values were compared
with Manning n values from laboratory tests on channels having similar grass
covers. Close agreement was found for poor grass, but not for fair and good
grass. The methods can be used to estimate the overland flow equation for an
ungaged watershed if a Manning n value for the overland flow surface can be es-
timated .
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77 :02E-006
COMPARISON OF ANNUAL STREAMFLOW MODELS,
Burges, S.J., and Lettenmaier, D.P.
Washington University, Department of Civil Engineering, Seattle, Washington.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY9, p 991-1006, September 1977. 9 fig, 1 tab, 22 ref, 2 append.
Descriptors: Model studies, Streamflow, Water resources, Streamflow forecasting.
The principle objective of this paper is to demonstrate the operational importance
of the form of model and the level of its parameters used for annual Streamflow
generation. Streamflow generation models most commonly used in practice at pre-
sent belong to the short-term memory category; models that preserve longer term
persistence features (Hurst effect (10, 11, 12}} are well understood but have
not been extensively used in water resource system evaluation. Models of the
second category are usually more expensive to operate than Markov models; thus
it is of interest to determine the operational importance of preserving both
short and long-term persistence effects.
10
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SECTION V
WATER CYCLE
GROUNDWATER (GROUP 02F)
77:02F-001
NUMERICAL PUMPING TEST ANALYSIS IN UNCONFINED AQUIFERS,
Rushton, K.R., and Chan, Y.K.
Birmingham University, Department of Civil Engineering, England.
Journal of the Irrigation and Drainage Division, American Society of Civil En-
gineers, Vol. 103, No. IR1, Proceedings Paper 12782, p 1-12, March 1977. 4 fig,
2 tab, 14 ref, 2 append.
Descriptors: *Aquifer testing, *Drawdown, *Numerical analysis, *Aquifers, Water
table, Computer models, Darcy's law, Groundwater movement, Water wells. Test wells,
Seepage, Storage, Percolation.
A numerical model was presented which describes the flow towards an abstraction
well in an unconfined aquifer. At each radius, the conditions within the aquifer
are described in terms of only two drawdowns, the free surface, and the average
drawdown. This model allowed the effects of vertical components of flow, variable
saturated depth, water contained within the well, delayed yield, and other factors
to be included in a single solution. Results from the numerical model were com-
pared with alternative analytical solutions. Finally, the technique was used to
interpret two pumping tests in unconfined -aquifers.
77:02F-002
TOWARD AN ANALYTICAL THEORY OF WATER FLOW THROUGH INHOMOGENEOUS POROUS MEDIA,
Gupta, V.K., Sposito, G., and Bhattacharya, R.N.
Arizona University, Department of Hydrology and Water Resources, Tucson, Arizona.
Water Resources Research, Vol. 13, No. 1, p 208-210, February 1977. 10 ref,
Descriptors: *Porous media, *Groundwater movement, *Darcy"s law, Flow, Fluid
mechanics, Analytical techniques, Mathematical studies. Equations, Mathematics,
Analysis.
Some rigorous mathematical results for the Buckingham-Darcy flux law for water
flow through an isotropic, nondeformable, inhomogeneous porous medium were pre-
sented. It was shown that the volumetric flux density vector, aside from the
component due to gravity, may always be expressed in terms of a scalar and a vec-
tor matric flux potential. The vector matric flux potential will vanish for a
homogeneous porous medium and for a one-dimensional inhomogeneous porous medium.
It follows from this result that the hydraulic conductivity will be a function
only of the water potential in any one-dimensional porous medium if its space
derivative at constant water potential vanishes identically. In addition, it was
shown that the vector matric flux potential is of no physical consequence insofar
as the flow equation is concerned, regardless of the number of dimensions of space.
The specifications of that part of the flux density vector contributed by the vec-
tor potential appears in the law of momentum balance instead of the law of mass
balance.
77:02F-003
COMPARISON OF ITERATIVE METHODS OF SOLVING TWO-DIMENSIONAL GROUNDWATER FLOW
EQUATIONS,
Trescott, P.C., and Larson, S.P-
Geological Survey, Water Resources Division, Reston, Virginia.
Water Resources Research, Vol. 13, No. 1, p 125-135, February 1977- 13 fig,
1 tab, 20 ref.
11
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Descriptors: *Groundwater movement, *Subsurface flow, *Model studies, *Mathemati
cal models, *Equations, Methodology, Evaluation, Correlation analysis, Aquiter
characteristics, Hydrogeology.
The efficiency of line successive overrelxation (LSOR) is compared with a_two-
dimensional correction procedure (2DC), the iterative, alternating direction
implicit procedure (ADI), and the strongly implicit procedure (SIP) to solve
finite-difference equations used to simulate several groundwater reservoirs.
Three of the reservoirs are linear, two are isotropic areal problems, and the
third is an anisotropic cross-section simulation. The fourth is a nonlinear water
table aquifer with areas of this saturation. SIP is generally the best method
for the linear simulations and with the addition of another iteration parameter
is the only method that gives an adequate rate of convergence for the water table
problem. LSOR with 2DC is competitive with SIP on isotropic and anisotropic
linear problems that are dominated by no-flow boundaries. ADI is generally more
efficient than LSOR if a good set of iteration parameters are used, but this advan-
tage is offset by the relative ease of finding the best acceleration parameter for
LSOR.
77:02F-004
DRAIN SPACING BASED ON DYNAMIC EQUILIBRIUM,
McWhorter, D.B.
Colorado State University, Department of Agricultural Engineering, Fort Collins,
Colorado.
Journal of the Irrigation and Drainage Division, American Society of Civil Engi-
neers, Vol. 103, No. IR2, Proceedings Paper 13022, p 259-271, June 1977. 3 fig,
4 tab, 13 ref, 2 append.
Descriptors: *Drains, *Water table, *Groundwater movement, *Mathematical models,
Equations, Aquifers, Groundwater recharge, Hydraulic properties, Flow, Depth,
Discharge (water), Saturated flow, Drawdown, Boundaries ( surfaces) .
Superposition was used to obtain an equation for the water table elevation between
parallel drains in response to a periodic sequence of instantaneous recharge events
of arbitrary volume and timing. The mathematical developments are especially use-
ful for calculating the spacing of parallel-relief drains required to achieve a
perscribed maximum water table elevation under conditions of "dynamic equilibrium."
A drain-spacing calculation, compared with the results obtained by the Bureau of
Reclamation's (USDI) approximate, dynamic-equilibrium method, showed the latter to
result in a drain spacing that is on the safe side. The spacing method reported
herein provides a mathematically correct alternative to the pioneering dynamic
equilibrium calculation and maintains the flexibility required to handle conditions
of variable recharge and drainout times.
77:02F-005
INFLUENCE OF MATRIX CONDUCTION UPON HYDROGEOPHYSICAL RELATIONSHIPS IN ARENA-
CEOUS AQUIFERS,
Worthington, P.P.
National Physical Research Laboratory, Geophysics Division, Pretoria (South Africa).
Water Resources Research, Vol. 13, No. 1, p 87-92, February 1977. 4 fig, 10 ref.
Descriptors: *Resistivity, *Sand aquifers, *Porosity, *Aquifers, Permeability,
Geophysics, Sandstones, Electrolytes, Groundwater, Salinity, Particle size, Clay
minerals.
The relationship of formation resistivity factor to effective porosity or inter-
granular permeability in water-saturated sands was shown to be best defined where
the solid constituents do not contribute significantly to the conduction of applied
current or where corrections for this contribution have been applied to the mea-
sured formation resistivities. It was demonstrated that, in the particular case
of an argillaceous sand sorted according to its matrix conduction properties, use-
ful relationships between formation resistivity factor and intergranular permeabil-
ity can be established without any process of correction, provided that porosity
and electrolyte salinity do not vary markedly within the formation. This finding
was used to resolve the paradox that formation resistivity factor has been report-
ed to increase with intergranular permeability in certain sands and to decrease
with increasing values of this same hydrological parameter in others.
12
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77:02F-006
DEVIATIONS FROM THE THEIS SOLUTION IN AQUIFERS UNDERGOING THREE-DIMENSIONAL
CONSOLIDATION,
Gambolati, G.
Centre di Ricerca IBM di Venezia (Italy).
Water Resources Research, Vol. 13, No. 1, p 62-68, February 1977- 7 fig
17 ref.
Descriptors: *Consolidation, *Aquifers, *Mathematical models. *Theoretical
analysis, *Theis equation, Finite element analysis. Equations, Drawdown,
Permeability, Aquifer testing, Storage coefficient, Depth, Compaction, Defor-
mation, Stress,Potentiometric level, Elastic deformation.
Previously, a new mathematical model based on the "tension center" or "strain
nucleus" concept was proposed for the response characterizing flow in a confined
aquifer undergoing three-dimensional consolidation. The new approach differs
from Biot's approach in that it leads to the development of a unique integro-
differential equation for the pressure head decline occurring within the porous
system. The consideration of the horizontal strain components results in a
conceptually simple modification of the classical diffusion equation to which
a further integrodifferential term accounting for the three-dimensional effect
is added. In the present paper, the new equation of flow was solved in a pump-
ed artesian aquifer inclosed in a half space by an iterative finite element
technique. It was shown that in shallow and relatively thick units (with W
approximately equal to 0.5, where W is the ratio between the average depth and
the thickness of the aquifer), downward vertical components of flow develop and
that the average drawn deviates moderately from the Theis solution and is no
longer uniquely represented against the dimensionless time. The three-dimen-
sional effect produces an additional soil compression which retards the piezo-
metric decline. At large values of time, the horizontal strain components
vanish, the diffusion equation holds, and the solution becomes parallel to the
Theis profile. As a major consequence, the traditional aquifer tests can still
be applied to assess the formation permeability, but they yield a 40% over-
estimate of the elastic storage coefficient. In deeper units (W greater than
0.5), the importance of the three-dimensional effect diminishes, is already
small when W equals 1, and becomes negligible for W greater than or equal to 2.
In this case, the diffusion equation and its solutions are sufficiently accurate.
From a practical standpoint, the quantitative results given herein are limited
by the condition that a mechanically homogeneous and isotropic half space is
required.
77:02F-007
THERMAL CONVECTION IN A CAVERNOUS AQUIFER,
Rubin, H.
Florida University, Department of Civil Engineering, Gainesville, Florida.
Water Resources Research, Vol. 13, No. 1, p 34-40, February 1977. 4 fig, 11 ref,
1 append.
Descriptors: *Thermal water, *Aquifers, *Groundwater movement, *Model studies,
Mathematical models. Convections, Fluid mechanics. Fluid friction, Permeability,
Groundwater, Temperature, Water temperature, Heat transfer.- Currents (water) ,
Stability, Equations, Porous media, Hydrology-
Geothermal activity may lead to convection currents in saturated permeable layers
within the earth. Instability criteria for such a flow field, in which the fluid
flows initially at moderate Reynolds numbers is discussed. Supercritical condi-
tions were analyzed by expanding the finite amplitude perturbations through trun-
cated eigenfunctions. This approach yielded expressions for the intensity of
transport processes through the aquifer. It was found that mechanical dispersion
due to convection motions reduces the intensity of transport processes.
77:02F-008
SHAPE OF A STREAMLINE WATER TABLE NEAR INFLOW AND OUTFLOW BOUNDARIES,
Boast, C.W.
Illinois University, Department of Agronomy, Urbana-Champaign, Illinois.
Water Resources Research, Vol. 13, No. 2, p 325-328, April 1977. 3 fig, 1 tab,
12 ref.
13
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Descriptors: *Water table, *Shape, *Boundaries (surfaces), *Flow nets. Mathema-
tical models, Inflow, Discharge, Slopes, Equations, Graphical analysis, Dupuit-
Forchheimer theory, Dams.
A streamline water table usually is pictured to leave an inflow boundary perpendi-
cular to the surface and to approach an outflow boundary tangential to the surface
for vertical surfaces or for inclined surfaces with the porous medium below the
surface. The hodograph solution for the problem of flow through a vertical walled
dam proved that, theoretically, the water table streamline leaves the inflow bound-
ary horizontally and approaches the outflow boundary vertically. However, tne
solution shows that at a practical scale the water table meets the boundaries at
finite nonzero slopes. The actual water table shape deviates considerably trom
the usual way that the water table is sketched. The cause of the difference lies
in an intuitive but incorrect assumption that the slope of the water table does
not change dramatically near the endpoints of the water table.
77:02F-009
LOCATION OF FREE SURFACE IN POROUS MEDIA,
Liggett, J.A.
Cornell University, Department of Civil Environmental Engineering, Ithaca, New
York.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY4, Proceedings Paper 12851, p 353-365, April 1977. 7 fig, 6 ref, 3 append.
Descriptors: *Free surfaces, *Porous media, *Mathematical models, Equations, Numer-
ical analysis, Boundaries (surfaces), Groundwater movement, Water table, Steady
flow, Unsteady flow. Permeability, Seepage.
The boundary integral equation method (BIEM) was applied to the problem of locating
the free surface in both steady and unsteady flow through porous media. The method
is numerical in its application and uses boundary data only. Thus, the position
of the free surface can be found without solving the complete flow problem. The
method can be continued to find the solution to the complete problem. The method
is especially efficient when the solution is desired at a limited number of points
(e.g., on a failure surface in determining slope stability) or in a limited area
of the flow. Examples were given in which there is a free surface and a seepage
surface and in which zones of different permeability appear.
77:02F-010
A METHOD OF ESTIMATING PARAMETERS AND ASSESSING RELIABILITY FOR MODELS OF STEADY
STATE GROUNDWATER FLOW 1. THEORY AND NUMERICAL PROPERTIES,
Cooley, R.L.
Geological Survey, Water Resources Division, Lakewood, Colorado.
Water Resources Research, Vol. 13, No 2, p 318-324, April 1977. 1 fig, 37 ref.
Descriptors: *Model studies, *Groundwater movement, *Least squares method, ^Steady
flow, Hydrogeology, Numerical analysis, Aquifer characteristics, Geohydrologic
units, Boundary layers, Sinks, Methodology, Forecasting, Regression analysis.
A new nonlinear least squares solution for the hydrogeologic parameters, sources
and sinks, and boundary fluxes contained in the equations approximately governing
two-dimensional or radial steady state groundwater motion was developed through
use of a linearization and iteration procedure applied to the finite element discre-
tization of the problem. Techniques involving (1) use of an iteration parameter to
interpolate or extrapolate the changes in computed parameters and head distribution
at each iteration and (2) conditioning of the least squares coefficient matrix
through use of ridge regression techniques were proven to induce convergence of the
procedure for virtually all problems. Because of the regression nature of the
solution for the parameter estimation problem, classical methods of regression
analysis are promising as an aid to establishing approximate reliability of com-
puted parameters and predicted values of hydraulic head. Care must be taken not
to compute so many parameters that the stability of the estimates is destroyed.
Reduction of the error variance by adding parameters is desirable provided that
the number of degrees of freedom for error remains large.
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77:02F-011
TRANSIENT ANALYSIS OF PHREATIC AQUIFERS LYING BETWEEN TWO OPEN CHANNELS,
Singh, S.R., and Jacob, C.M.
Punjab Agricultural University, Department of Soil and Water Engineering,
Ludiana (India).
Water Resources Research, Vol. 13, No. 2, p 411-419, April 1977. 3 fig 1 tab,
16 ref.
a
Descriptors: *Aquifers, *Groundwater movement, *Hydrodynamics, *Model studies,
Mathematical models, Groundwater, Channels, Hydraulic conductivity, Water table,
Water levels, Precipitation (atmospheric), Infiltration, Recharge, Withdrawal,
Hydraulics.
The unsteady-state flow of water through an unconfined aquifer can be represented
by the Boussinesq equation. The nonlinear term involving the highest derivative
in this equation was approximated by a linear term, and the resulting approxi-
mate Boussinesq was linearized to a Fokker-Planck equation by the method of func-
tional transformation. Solutions to the problem of groundwater flow through
phreatic aquifers lying between (1) constant water level boundaries and (2)
variable water level boundaries were obtained from the general solution of the
Fokker-Planck equation for constant and variable rates of recharge and withdrawal.
Variable rates of recharge and withdrawal were approximated by periodic step
functions which represented two different rates, one each for both rainy and dry
seasons. Variable water levels in the open channels were approximated by step
functions and the initial condition was represented by straight line segments.
An analytical solution of the approximate Boussinesq equation was compared with
the finite difference solution of the original Boussinesq equation. The difference
between the two solutions was almost negligible, and therefore, the applicability
of the analytical solutions to groundwater resource management was established.
The effect of variable water level boundaries on groundwater dynamics was studied
by performing a sample calculation.
77:02F-012
FLOW IN FRACTURED POROUS MEDIA,
Duguid, J.O., and Lee, P.C.Y.
Princeton University, Department of Civil Engineering, New Jersey.
Water Resources Research, Vol. 13, No 3, p 558-566, June 1977. 6 fig, 17 ref.
Descriptors: *Porous media, *Mathematical models, *Fracture permeability, *Flow,
Model studies, Mathematical studies. Theoretical analysis, Analytical techniques,
Numerical analysis, Finite element analysis, Equations, Porosity, Compressibility.-
Subsurface flow.
The equations governing the flow of fluid through fractured porous media were de-
rived. The equations consist of Darcy's law for fluid flow in the primary pores,
equations of motion for fluid flow in the fractures, and two continuity equations.
The system of equations was coupled by the interaction of fluid in the primary
pores with fluid in the fractures. The coupling terms, which are incorporated
in the continuity equations, describe the transient flux of fluid out of the pri-
mary pores and into the fractures. The finite element Galerkin method was used
to solve the coupled system of equations for transient flow in a confined leaky
aquifer. Solutions were obtained for both constant discharge and step drawdown
problems. The importance of coupling the primary blocks to the fracture .system
and the effect of the acceleration term in the equation of motion in the fractures
were studied by using the model. The effect of the acceleration term in the equa-
tion of motion of fluid in fractures is small, even in the case of step drawdown,
where there is a rapid change in the magnitude of velocity during early stages of
the flow. Both the incremental pressure in the primary pores and the total incre-
mental pressure in the fractures were obtained from the mathematical model. The
two pressures cannot be obtained from an observation well because the level mea-
sured in the well is related to total pressure. The pressure in the fractures is
nearly equal to the pressure in the primary pores, and the gradients of these
pressures are nearly equal.
77:O2F-013
VISCOELASTIC AQUIFER MODEL APPLIED TO SUBSIDENCE DUE TO PUMPING,
Corapcioglu, M.Y., and Brutsaert, W.
Cornell University, School of Civil and Environmental Engineering, Ithaca, New York.
15
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water Resources Research, VoL 13, No 3, p 597-604, June 1977. 2 fig, 3 tab,
46 ref.
Descriptors: *Land subsidence, California, *Mathematical models, *Aquifers,
*Pumping, Model studies, Water level fluctuations, Compaction, Drawdown,
Theoretical analysis, Consolidation.
A viscoelastic aquifer model was applied to analyze and predict the piezometric
drawdown and the compaction observed in a major confined aquifer system in the
San Joaquin Valley in California. A field approach was used based_on_a^minimal
number of "bulk "parameters. The parameters, which are the transmissivity,
the compressibilities of primary and secondary consolidation, and the viscosity
of the secondary consolidation, were derived by calibration of the model by
means of trial and error simulation of 2 years of records of drawdown and^com-
paction. It was found that in the absence of drawdown records, the identifica-
tion also may be accomplished with compaction records in addition to a standard
pumping test. Comparison of computed results with available records showed that
the viscoelastic model yields a satisfactory prediction of compaction which^is
far better than that obtainable with the elastic model of the classical Theis-
Jacob approach. The elastic model may be adequate to represent the hydraulic
properties of the aquifer in the analysis of the piezometric drawdown; however,
it appears to be unsatisfactory to represent the mechanical properties of the
aquifer as related to surface subsidence.
77:O2F-014
NUMERICAL MODEL FOR SATURATED-UNSATURATED FLOW IN DEFORMABLE POROUS MEDIA, I .
THEORY,
Narasimhan, T.N., and Witherspoon, P.A.
California University, Lawrence Berkeley Laboratory; and California University-
Department of Mineral Sciences and Mineral Engineering, Berkeley, California.
Water Resources Research, Vol. 13, No 3, p 657-664, June 1977. 6 fig, 27 ref.
Descriptors: *Porous media, *Mathematical models, *Groundwater movement, Theo-
retical analysis. Saturated flow, Unsaturated flow, Model 'studies, Deformation,
Numerical analysis, Equations, Flow, Groundwater, Hydrology, Permeability,
Compressibility, Pore water, Hydraulic conductivity.
A theory was presented for numerically simulating the movement of water in var-
iable saturated deformable porous media. The theoretical model considered a
general three-dimensional field of flow in conjunction with a one-dimensional
vertical deformation field. The governing equation expressed the conservation
of fluid mass in an elemental volume that has a constant volume of solids. De-
formation of the porous medium may be nonelastic. Permeability and the compres-
sibility coefficients may be nonlinearly related to effective stress. Relation-
ships between permeability and saturation with pore water pressure in the
unsaturated zone may be characterized by hysteresis. The relation between pore
pressure change and effective stress change may be a function of saturation. In
the transition zone where pore.water pressure is less than atmospheric but greater
than air entry value, soil moisture diffusivity as used in soil physics and coef-
ficient of consolidation as used in soil mechanics were shown to be conceptually
equivalent. It is believed that the model will be of practical interest in
studying saturated-unsaturated systems undergoing simultaneous desaturation and
deformation.
77:02F-015
SEEPAGE UNDER STRUCTURE ON N STRATA OF SOIL,
Lenau, C.W.
Missouri University, Department of Civil Engineering, Columbia, Missouri.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY5, Proceedings Paper 12911, p 483-497, May 1977. 4 fig, 2 tab, 2 ref, 4
append.
Descriptors: *Underseepage, *Stratification, *Hydraulic structures, *Mathemati-
cal models, Equations, Groundwater movement, Underflow, Seepage, Permeability,
Aquifers, Confined water, Artesian heads. Dams.
16
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A solution was developed for the discharge under a structure resting on N strata
of equal thickness. The solution was an asymptotic approximation of the exact
solution for large values of the structure length. However, because neglected
terms are exponentially small, the solution is accurate for a very wide range of
conditions. Because successive strata can have equal permeability, the solution
can be applied to almost any combination of strata thicknesses and permeabilities.
77:02F-016
HYDROGEOCHEMICAL RELATIONSHIPS USING PARTIAL CORRELATION COEFFICIENTS,
Barr, D.E., and Newland, L.W.
Texas Christian University, Environmental Sciences Program, Fort Worth, Texas.
Water Resources Bulletin, Vol. 13, No. 4, Paper No. 77073, p 843-846, August 1977.
1 tab, 4 ref.
Descriptors: *Water chemistry, *Groundwater, *Correlation analysis, *Geochemistry,
Ions, Cations, Calcium, Sodium, Magnesium, Chlorides, Sulfates, Data processing,
Analytical techniques, Groundwater resources.
Analyses of 69 groundwater samples were performed for 6 chemical parameters. Par-
tial and simple correlation coefficients for the parameters indicate that partial
coefficients are superior to simple coefficients in establishing geochemical re-
lationships for the aqueous system evaluated. The improved reliability arises
from the ability of partial correlation analysis to hold constant the outside fac-
tors that may be affecting the two variables of interest.
77:02F-017
TRANSIENT SPHERICAL FLOW TO A CAVITY WELL OF FINITE DIAMETER,
Jaiswal, C.S., Chauhan, H.S., and Ghildyal, B.P-
Govind Ballabh Pant University of Agriculture and Technology, Department of
Agricultural Engineering, Pantnagar (India).
Ground Water, Vol. 15, No. 5, p 372-376, September-October 1977. 4 fig, 3 tab,
12 ref.
Descriptors: *Flow, *Groundwater movement, *Wells, Transmissivity, Storage coef-
ficient, Aquifers, Hydrology, Groundwater, Mathematical studies. Analysis.
The system of flow into a nonpenetrating well with hemispherical bottom of finite
radius in a finite deep artesian aquifer of infinite radial extent was analyzed.
The solution was obtained in terms of error function. A method was suggested
for determination of transmissivity, storage coefficient, and depth of aquifer
from pump test data of such wells discharging at constant rate. For small values
of radial distance to aquifer depth ratio and for small duration test, only a few
were required in the present solution as compared to the solution of Hantush
developed for such wells.
77:02F-018
MODELING OF UNCONFINED GROUNDWATER SYSTEMS,
Murray, W.A., and Johnson, R.L.
Lehigh University, Department of Civil Engineering; and Lehigh University, Fritz
Engineering Laboratory, Bethlehem, Pennsylvania.
Ground Water, Vol. 15, No. 4, p 306-312, July-August 1977- 2 fig, 1 tab, 34 ref,
2 append.
Descriptors: *Groundwater, *Equations, *Model studies, Groundwater movement,
Dupuit-Forchheimer theory, Mathematical models, Water table, Hydrology, Base flow.
Mathematical modeling of regional unconfined groundwater flow is accomplished most
often by using a linearized Dupuit-Forchheimer (DF) equation. The depth of flow,
h, in the general DF equation appears as a squared h term and also as a linear
term of h. Linearization of the DF equation generally is accomplished^with^the
first method of linearization presented by Polubarinova-Kochina (PK), in which
squared h is replaced with h times some average, depth of flow. The resulting
equation is then linear in h. The second method of linearization described by PK
is accomplished by replacing h with squared h, divided by an average flow depth,
and hence the resulting equation becomes linear in squared h. If the second
method of linearization is used, the same heat conduction type equation is obtained
17
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as that from the first method of linearization, but it tends to yield more accu-
rate predictions of water table locations. Furthermore, by simply altering the
numerical values of boundary condition constants, most existing mathematical
models, based on the first method of linearization can be easily converted to yield
solutions to the more accurate equation linearized by the second method.
DIGITAL MODEL STUDIES OF STEADY-STATE RADIAL FLOW TO PARTIALLY PENETRATING WELLS
IN ALLUVIAL PLAINS,
Lakshminarayana, V., and Rajagopalan, S.P.
Indian Institute of Technology, Department of Civil Engineering, Kanpur.
Ground Water, Vol.15, No 3, p 223-230, May-June 1977. 5 fig, 4 tab, 4 ref.
Descriptors: *Groundwater, *Groundwater movement, *Water wells, *Model studies,
Mathematical models, Drawdown, Wells, Water levels, Water table, Flow, Aquifers,
Screens, Well screens, Permeability, Anisotropy, Pumping, Computer models.
A digital simulation model for the steady-state radial flow towards partially
penetrating wells in the alluvial plains was presented. As the deposits in these
plains are heterogeneous with several good water-bearing formations crisscrossed
with silty layers, the deposits were treated as a single anisotropic aquifer^with
water table conditions prevailing. The iterative alternate direction implicit
technique was used for the solution of the steady-state flow. The digital simula-
tion model was used to study the effects of anisotropy, screen setting, and
screen length on the discharge per unit length of screen. The model also was used
to evaluate the errors involved in determining lateral permeability from distance-
drawdown data. The digital simulation model was applied to field pump-test data
for purposes of identification of aquifer anisotropy and radius of influence of
well; and the model was used in evaluation of errors in determining lateral per-
meability from distance-drawdown data.
77:02F-020
A MATHEMATICAL MODEL STUDY OF FRESH-WATER LENSES,
Chidley, T.R.E., and Lloyd, J.W.
Aston University, Department of Civil Engineering, Birmingham (England).
Ground Water, Vol 15, No 3, p 215-222, May-June 1977. 8 fig, 9 ref.
Descriptors: *Groundwater, *Islands, *Model studies. Mathematical models. Saline
water-freshwater interfaces, Aquifers, Permeability, Water levels, Fluctuations,
Water levels fluctuations, Groundwater movement, Groundwater recharge, Ground-
water resources.
An analysis of the unsteady flow in a freshwater lens on a small tropical thick-
ness. An alternative view of the problem to that most commonly given was present-
ed. Results were shown for some lenses on Grand Cayman Island in the Caribbean
Sea. The aquifer material is a micro-first limestone. The chief result of engi-
neering significance was that the conventional steady-state analysis was shown
to be a sound basis for estimating the long-term yield if drought sequences are
not long.
77:02F-021
APPLICATIONS OF SURFACE RESISTIVITY METHODS,
Schwartz, F.W., and McClymont, G.L.
Alberta University, Department of Geology, Edmonton, Alberta, Canada.
Ground Water, Vol. 15, No. 3, p 197-202, May-June 1977. 5 fig, 10 ref.
Descriptors: *Groundwater, *Surveys, *Resistivity, *Canada, Geology, Geophysics,
Rock properties, Conductivity, Electrical resistance, Borehole geophysics, Sand-
stones, Glacial drift, Aquifers, Groundwater potential, Groundwater resources,
Hydrogeology.
Generally, the geology of the Breton area of Alberta consists of a 5- to 125-ft.
veneer of glacial till overlying sandstone and sandy shale units of the Paskapoo
Formation. These sandstone units are locally important aquifers. Glacial drift
in the Hastings Lake area varies in thickness from 100 to 200 ft, and overlies
the Horseshoe Canyon Formation, which consists of bentonitic shale, siltstone,
and coal units with minor sandstone units. Groundwater yields from drift and
18
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bedrock in this area are generally less than 30 gpm (113.6 1/m). Resistivity
soundings were completed at 68 and 65 stations in the Breton and Hastings Lake
areas, respectively. Profile maps from the Breton area are characterized by
broad areas with apparent resistivity values greater than 100 ohm-ft. Qualita-
tive evaluation of the resistivity soundings and existing borehole data indi-
cated that the high resistivity values resulted from a thick resistive sandstone
aquifer less than 25 ft- from ground surface. A reasonably well-defined resisti-
vity pattern was evident on the profile maps of the Hastings Lake area, with the
highest resistivity values coming from stations located in the hummocky moraine
south of the lake. In addition to providing useful information on the geology
of an area, surface resistivity methods provide a rapid and relatively inexpen-
sive tool to aid in planning more detailed groundwater studies because of their
ability to detect inhomogeneities in the subsurface environment.
77:02F-022
UTILIZING A DIGITAL MODEL TO DETERMINE THE HYDRAULIC PROPERTIES OF A LAYERED
AQUIFER,
Land, L.F.
Geological Survey, Bay Saint Louis, Missouri.
Ground Water, Vol.15, No 2, p 153-159, March-April 1977. 6 fig, 1 tab, 13 ref.
Descriptors: *Model studies, *Hydraulic properties, *Aquifer systems, *Computer
models, Groundwater movement, Hydraulic conductivity, Storage coefficient, Trans-
mis sivity-
The hydraulic characteristics of a layered groundwater system are determined by a
modified digital model. Its use provides information on the hydraulic conducti-
vity and storage coefficient of a stratum and on the transmissivity and storage
coefficient of the groundwater system as a whole. These characteristics are
determined by trial and error test runs until the calculated drawdowns reasonably
match drawdown data from observation wells which are open to the artesian aquifer
and to the confining beds above or below. An aquifer test of a layered ground-
water system in Palm Beach County , Florida, shows that the transmissivity of the
groundwater system as a whole is 50 percent higher than just the transmissivity
of the major water-bearing zone in this system.
77:02F-023
ANALYTIC SOLUTION FOR DRAWDOWN IN AN UNCONFINED-CONFINED RECTANGULAR AQUIFER,
Chan, Y.K., Mullineux, N., and Reed, J.R.
Birmingham University, Department of Mechanical Engineering, (England).
Journal of Hydrology, Vol. 34, No. 3/4, p 287-296, August 1977. 3 fig, 2 ref,
1 append.
Descriptors: *Drawdown, *Aquifers, *Mathematical models, *Equations, *Rainfall,
*Groundwater, Water wells. Pumping, Confined water, Aquifer characteristics.
Analytical solutions for the drawdowns due to pumping from a rectangular, uncon-
fined-confined aquifer subject to rainfall on the unconfined part were given. A
solution with general rainfall and with time counted from the start of abstraction
was shown to involve more extensive computation than is usually warranted. The
amount of computation can be very considerably reduced by considering the rainfall
to be periodic (either x-dependent or uniform) and by seeking the eventual periodic
drawdown. Since the problem is linear, the drawdown due to a number of abstrac-
tion wells in the confined aquifer is merely the sum of the drawdowns due to each
individually.
77:02F-024
LONGITUDINAL DISPERSION IN POROUS MEDIA WITH VARIABLE POROSITY,
Lin, S.H.
Melbourne University, Department of Chemical Engineering, Parkville (Australia).
Journal of Hydrology, Vol 34, No 1/2, p 13-19.- July 1977- 3 fig, 13 ref.
Descriptors: *Porous media, *Porosity, *Dispersion, Aquifers, Groundwater,
Saline water intrusion, Hydrology, Equations, Model studies, Mathematical studies,
Oil reservoirs.
19
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An analytical procedure was developed for predicting the solute dispersion in por-
ous media with variable porosity and constant volumetric seepage flow rate. Sev-
eral porosity equations, which may represent the possible porosity variation as a
function of spatial coordinate, were suggested and used to test how well the pre-
dicted solute concentration using a constant average porosity is when compared to
the prediction using a prescribed porosity function. It was found that the pre-
dictions by using an average porosity are within 15% of those predictions using a
linear or a slightly curved, porosity function. However, the discrepancy between
the two predictions is very substantial as the porosity function becomes a strong
nonlinear one. For this instance, prediction of the solute concentration using
an average porosity is rather poor, and a numerical method is needed if a reliable
prediction is to be obtained.
77:02F-025
COMPUTER MODELING OF REGIONAL GROUNDWATER SYSTEMS IN THE CONFINED-UNCONFINED
FLOW REGIME,
Birtles, A.B., and Reeves, M.J.
Department of the Environment, Central Water Planning Unit, Reading (England).
Journal of Hydrology, Vol.34, No 1/2, p 97-127, July 1977. 13 fig, 47 ref.
Descriptors: *Groundwater, *Groundwater movement, *Model studies, Mathematical
models, Aquifers, Sandstones, Infiltration, Discharge (water), Flow, Foreign
research, Computer models, Recharge, Water levels. Pumping, Leakage, Hydrology.
The concepts and philosophies underlying the development of general purpose com-
puter programs for the simulation of groundwater flow in regional aquifer systems
operating in the confined-unconfined flow regime were described. The most impor-
tant of the many variables at play in such systems and the mechanisms by which
they interact were identified, and the data required for the numerical definition
of the hydrological system were reviewed. Emphasis was laid upon the importance
of modeling physical processes as precisely as possible when computer predictions
outside the scope of natural hydrological events are to be attempted. An example
was given of an application of the computer programs and techniques to the inves-
tigation of a proposed river regulation scheme using groundwater abstractions.
77:02F-026
PERMISSIBLE MESH SPACING IN AQUIFER PROBLEMS SOLVED BY FINITE DIFFERENCES,
Rushton, K.R., and Tomlinson, L.M.
Birmingham University, Department of Civil Engineering, Birmingham University
(England).
Journal of Hydrology, Vol.34, No 1/2, p 63-76, July 1977. 6 fig, 4 tab, 12 ref,
append.
Descriptors: *Aquifers, *Groundwater, *Model studies, Mathematical models, Finite
element analysis, Groundwater movement, Analytical techniques, Computer models.
Hydrology.
The maximum acceptable mesh spacing for finite-difference models of groundwater
flow problems was investigated by analyzing a range of problems for which alterna-
tive solutions are available. It was shown that, for long time periods or for
problems in which the head variation is smooth, a few mesh subdivisions are often
acceptable; but for other problems, many mesh subdivisions are essential. Recom-
mendations were given for the design of a mesh; the validity of the design was
tested in the solution of two field problems.
77:02F-027
ECONOMIC IMPACT OF DIMINISHING GROUNDWATER RESERVES ON CORN PRODUCTION UNDER
CENTER-PIVOT IRRIGATION,
Sanghi, A.K., and Klepper, R.
Washington University, Center for the Biology of Natural Systems, St. Louis,
Missouri 63130.
Journal of Soil and Water Conservation, Vol. 32, No. 6, p 282-285, November-
December, 1977. 4 tab, 18 ref.
Descriptors: Groundwater, Groundwater resources, Groundwater basins, Groundwater
potential, Aquifers, Corn, Sprinkler irrigation, Irrigation, Nebraska, Crop re-
sponse, Crop production, Water conservation.
20
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A method for analyzing the on-farm economic consequences of diminishing groundwater
reserves was developed. The method uses two functions. One relates well yield to
an aquifer's saturated thickness. The other is a yield-response function that
recognizes a critical period of plant growth. The application of the method to corn
under center pivot irrigation in Holt County, Nebraska, showed net returns to be
far more sensitive to insufficient irrigation water during the critical period of
corn growth than to price increases for energy or other inputs. The analysis also
suggested that farmers motivated by short-run economic gain will find it profitable
to modify wells to sustain well yield as water tables decline. Conservation of
groundwater, therefore, cannot be left to market forces.
77:02F-028
STUDIES ON SALINIZATION OF GROUNDWATER, I. THEORETICAL CONSIDERATION ON THE THREE-
DIMENSIONAL MOVEMENT OF THE SALT WATER INTERFACE CAUSED BY THE PUMPAGE OF CONFINED
GROUNDWATER IN FAN-SHAPED ALLUVIUM,
Kishi, Y., and Fukao, Y.
Ehime University, Department of Applied Physics, Matsuyama (Japan).
Journal of Hydrology, Vol. 35, No. 1/2, p 1-29, October 1977. 8 fig, 8 ref,
2 append.
Descriptors: *Groundwater flow, *Sea water, *Saline water intrusion, *Saline
water-freshwater interfaces, *Alluvial fans, Mathematical models, Confined water,
Pumping, Equations, Numerical analysis, Hydraulic conductivity, Density, Carey's
law. Boundaries (surfaces).
A theoretical model was presented on the phenomenon of seawater intrusion into
confined groundwater to make clear the relationship between the amount of pumping
of freshwater and the corresponding three-dimensional spatial distribution of salt
water. First, differential equations were derived for the fresh and salinized
regions, respectively, from the fundamental equation of confined water. The equa-
tion in the salinized region, which is a quasilinear differential equation, can
be transformed to a linear one and then is continued to the equation in the fresh
region, resulting in the two-dimensional Poisson's equation which is applicable
to the entire region. The equation in steady-state was solved in integral form
by using the method of Green's functions and was expressed simply in the case of
idealized field conditions analogous to a fan-shape alluvium by the usual method
of images. Finally, some numerical examples were shown for the case of uniform
pumpage in a circular region.
77:02F-029
SOLUTION OF THREE-DIMENSIONAL GROUNDWATER FLOW EQUATIONS USING THE STRONGLY
IMPLICIT PROCEDURE,
Trescott, P.C., and Larson, S,P.
Geological Survey, Water Resources Division, Reston, Virginia.
Journal of Hydrology, Vol. 35, No 1/2, p 49-60, October 1977, 6 fig, 17 ref, append.
Descriptors: *Model studies, *Groundwater movement, *Aquifer characteristics,
*Numerical analysis, *Computer programs, Hydrogeology, Leakage, Hydraulic
conductivity.
A three-dimensional numerical model has been coded to use the strongly implicit
procedure for solving the finite-difference approximations to the groundwater
flow equation. The model allows for: (1) the representation of each aquifer and
each confining bed by several layers; and (2) the use of an anisotropic hydraulic
conductivity at each finite-difference block. The model is compared with a pre~
viously developed quasi-three-dimensional model by simulating the steady-state
flow in an aquifer system in the Piceance Creek Basin, Colorado, The aquifer
system consists of two aquifers separated by a leaky confining bed. The upper
aquifer receives recharge from precipitation and is hydraulically connected to
streams. In order to make a valid comparison of results, a single layer was used
to represent each aquifer. The need for a layer to represent the confining bed
was eliminated by incorporating the effects of vertical leakage into the vertical
component of the anisotropic hydraulic conductivity of the adjacent aquifers.
Thus, the problem was represented by only two layers in each model with a total
of about 2,100 equations. This restricted the effects of flow in the confining
layer to the vertical components, but simulations with a third layer in the three-
dimensional model permitting horizontal flow in the confining bed show that the
21
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two-layer approach is reasonable. Convergence to a solution of this problem
takes about one minute of computer time on the IBM/155. This is about 30 times
faster than the time required using the quasi-three-dimensional model.
77:02F-030
CARBON DIOXIDE IN THE ATMOSPHERE OF THE UNSATURATED ZONE: AN IMPORTANT CONTROL
OF GROUNDWATER HARDNESS IN LIMESTONES,
Atkinson, T.C.
University of East Anglia, School of Environmental Sciences, Norwich (England).
Journal of Hydrology, Vol. 35, No. 1/2, p 111-123, October 1977. 6 fig, 4 tab,
30 ref.
Descriptors: *Carbon dioxide, *Hardness (water) , *Groundwater, *Limestones,
Caves, Springs, Spring water, Calcium, Calcite, Alkalinity, Water chemistry,
Organic material, Groundwater movement, Atmosphere, Unsaturated flow, Chemistry,
Hydrogeology, Hydrology.
Weekly analyses of springwaters in the Mendip Hills, England, showed constant
partial pressure of C02. Soil air partial pressure of C02 (measured directly
and calculated from soil water analyses) fluctuates seasonally and is almost
always less than the partial pressure of C02 of springs, A source of C02 in
the unsaturated zone was proposed to account for the discrepancy, supported by
direct measurements of C02 in fractures in cave walls and analyses of drip waters.
The partial pressure of C02 increases with depth, and values at the bottom of
caves are similar to spring waters. A possible source is decay of downwashed soil
organic matter.
77:O2F-031
MATHEMATICAL MODELING OF NATURAL GROUNDWATER RECHARGE,
Krishnamurthi, N., Sunada, O.K., and Longenbaugh, R.A.
Utah International Inc., Environmental Quality Department, San Francisco, Califor-
nia.
Water Pesources Research, Vol. 13, No. 4, p 720-724, August 1977. 4 fig, 15 ref.
Descriptors: *Groundwater recharge, *Model studies, *Mathematical models, Soil
water, Soil moisture, Capillary action, Pore pressure, Infiltration, Computer
models.
A mathematical model was presented which determines natural groundwater recharge
by using transient soil moisture data measured as a function of vertical position.
The model was based upon the finite difference form of the Richards equation. The
assumption was made that moisture content varies in the linear range of pressure-
moisture and conductivity-moisture relations to obtain a solution to a particular
field problem. The parameters of the model, estimated by a linear model of the
moisture data, characterize the hydraulic properties of soil and their spatial
variability. The finite difference form of the mathematical model was solved
by iteration using the Newtonlike method, ensuring computational speed and accur-
acy. The model and the computer program were verified by using the first-order,
approximate, one-dimensional solution of the infiltration equation for homogene-
ous soil. Application of the model to the High Plains of Colorado provided monthly
recharge rates which correlate adequately with the time series data of water table
elevations and events of precipitation and ephemeral streamflow,
77:02F-032
WATER TABLE RESPONSE TO A SEQUENCE OF RECHARGES,
Chu, S.T.
South Dakota State University, Department of Agricultural Engineering, Brookinqs,
South Dakota.
Water Resources Research, Vol. 13, No. 4, p 738-742, August 1977, 3 fig, 3 tab
11 ref.
Descriptors: *Water table, *Subsurface drainage, *Model studies, *Recharge, *Gro-
undwater recharge. Mathematical models, Tile drainage, Soil water, Groundwater,
Drainage, Fluctuations, Hydraulic conductivity. Agriculture.
22
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Water table behavior under subsurface drainage conditions was analyzed by consid-
ering water table fluctuations in response to a sequence of recharge events. The
derived solution is applicable to a nonhomogeneous soil profile. An iteration
procedure was introduced to illustrate the application of the theoretical results.
Agreement between theoretical analysis and field data was shown to be adequate.
77:02F-033
MACROSCOPIC DISPERSION IN POROUS MEDIA: THE CONTROLLING FACTORS,
Schwartz, F.W.
Alberta University, Department of Geology, Edmonton, Alberta, Canada.
Water Resources Research, Vol. 13, No. 4, p 743-752, August 1977. 7 fig, 10 ref,
1 append.
Descriptors: *Dispersion, *Porous media, *Model studies, *Groundwater movement,
Mathematical models, Hydraulic conductivity, Permeability, Porosity, Pores, Soil
water. Soil water movement, Soils, Soil science, Groundwater, Subsurface flow.
One of the most important limitations to the application of modeling techniques
for the analysis of mass transfer in groundwater systems is the difficulty in
characterizing the dispersive character of natural systems. Although large
quantities of experimental data exist for laboratory scale experiments, the hand-
ful of measurements which have been obtained from regional systems suggest that
dispersion produced by large-scale porous medium nonidealities is considerably
more important. The effects of macroscopic dispersion were simulated for uniform
heterogeneous porous media under conditions of one-dimensional flow. The idealized
media considered for detailed analysis consisted of low-permeability inclusions
within a higher-permeability medium. When the inclusions are not arranged rather
homogeneously within the region, a unique dispersivity value for the medium cannot
be defined, and dispersivity changes as a function of space. The magnitude of
dispersion is controlled by the contrast in hydraulic conductivity between the
inclusions and the remainder of the medium, the number of inclusions, and the mode
of aggregation. Generally, dispersivity was found to decrease as the conductivity
contrast decreases and the structure of the medium is regularized. It will be
possible to estimate the dispersivity of a medium by using stochastic analysis.
Hypothetical porous media with characteristics similar to those of some actual
medium will yield a range of dispersivity values. The basic data for the tech-
nique will be detailed statistical analysis of the mode of porous medium aggre-
gation and the conductivity contrasts within the medium.
77:02F-034
SIMILARITY SOLUTIONS FOR CONVECTION OF GROUNDWATER ADJACENT TO HORIZONTAL IMPER-
MEABLE SURFACES WITH AXISYMMETRIC TEMPERATURE DISTRIBUTION,
Cheng, P., and Chau, W.C.
Hawaii University, Department of Mechanical Engineering, Honolulu.
Water Resources Research, Vol. 13, No. 4, p 768-772, August 1977, 8 fig, 2 tab,
12 ref.
Descriptors: *Groundwater movement, *Convection, *Water temperature, *Model
studies, Mathematical models, Porous media, Groundwater, Heat transfer, Tempera-
ture, Heat flow, Heated water, Velocity, Permeability.
The axisymmetric buoyancy-induced groundwater flow adjacent to horizontal imper-
meable surfaces, wall temperature being a power function of radius, was discussed
in this paper. With the boundary layer simplifications, the governing nonlinear
partial differential equations can be transformed into a coupled pair of nonlinear
ordinary differential equations with two-point boundary conditions that can be
integrated numerically by established techniques. Simple algebraic expressions
for boundary layer thickness and heat transfer rate were obtained. Applications
to free convective flow in a liquid-dominated geothermal system at high Rayleigh
numbers were discussed.
77:02F-035
GROUNDWATER STORAGE RIGHTS IN THE WESTERN STATES,
Aiken, J.D.
Nebraska-Lincoln University, Department of Agricultural Economics, Lincoln,
Nebraska.
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Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p. 1-17-
Descriptors: Groundwater, Groundwater recharge, Groundwater basins, Ground-water
resources, Legal aspects, Legislation.
This paper summarizes statutes and related court cases from California and
Washington relating to the artificial storage and recapture of groundwater.
The paper also discusses some legal considerations states should consider in
establishing regulations for the artificial storage of groundwater.
77:02F-036
GEOELECTRIC SOUNDING FOR ESTIMATING AQUIFER HYDRAULIC CONDUCTIVITY,
Kelly, W.E.
Rhode Island University, Department of Civil and Environmental Engineering,
Kingston, Rhode Island.
Ground Water, Vol. 15, No. 6, p 420-425, November-December , 1977. 5 fig, 3 tab,
17 ref.
Descriptors: *Hydraulic conductivity, *Resistivity, *Electrical resistance,
*Rhode Island, On-site investigations, Aquifers, Pump testing, Hydrologic pro-
perties, Permeability, Conductivity, Measurement, Equipment, Data processing,
Regression analysis, Groundwater, Hydrology.
The objective of this study was to develop surface electrical resistivity methods
for estimating hydraulic conductivities in glacial outwash materials. Aquifer
electrical resistivities were determined from the results of Schlurnberger electri-
cal soundings at six sites in southern Rhode Island where pumping tests had pre-
viously been made. Hydraulic conductivities and transmissivities determined
from pumping tests then were correlated with resistivities obtained from electrical
soundings. Results indicated that electrical resistivities determined from sound-
ings can be used to predict aquifer hydraulic conductivities; -an empirical was
developed. A semiempirical relation between aquifer formation factor and hydraulic
conductivity also was developed.
77:02F-037
THE SIGNIFICANCE AND PREDICTION OF OBSERVATION WELL RESPONSE DELAY IN SEMI-
CONFINED AQUIFER-TEST ANALYSIS,
Black, J.H., and Kipp, K.L., Jr.
Institute of Geological Sciences, Department of Hydrogeology, London (England).
Ground Water, Vol. 15, No. 6, p 446-451, November-December, 1977. 4 fig, 1 tab,
10 ref.
Descriptors: *0bservation wells, *Water levels, *Aquifer testing, *Graphical
analysis, *Curves, Aquifers, Pumping, Equations, Leakage, Aquitards, Aquicludes,
Drawdown, Transmissivity, Storage coefficient, Hydraulic conductivity.
The concept of the observation well as a measuring instrument with its own response
characteristics was developed, and a method for response evaluation was derived
based on methods of slug-test analysis. The effect of well response time upon the
results of semiconfined aquifer tests was calculated, and a series of type curves
was produced. The ambiguity of observation well response affected leaky aquifer
tests was demonstrated. A method for calculating well response time based on es-
timates of aquifer parameters and observation well dimensions also was presented
to aid the proper design of aquifer tests. It was recommended that a slug test
should be performed on every observation well used in confined or semiconfined
aquifer tests.
77:02F-038
DETERMINATION OF TRANSPORT MODEL PARAMETERS IN GROUNDWATER AQUIFERS,
Murty, V.V.N., and Scott, V.H.
Punjab Agricultural University, Department of Soil and Water Engineering,
Ludhiana, India.
Water Resources Research, Vol. 13, No. 6, p 941-947, December 1977. 1 fig, 6 tab,
20 ref. 23 equ.
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Descriptors: Hydrodynamics, Groundwater, Aquifers, Model studies, Groundwater
resources, Groundwater movement.
The hydrodynamic dispersion coefficients in groundwater aquifers can be deter-
mined from observed values of solute concentrations. For a two-dimensional
aquifer in which the concentrations of a solute are known, an algorithm is de-
veloped to determine the values of longitudinal and transverse dispersivities.
Concentration polynomials are developed by using double interpolation for a set
of selected values of longitudinal and transverse dispersivities. With two of
the polynomials, Newton's method is used to find the roots which are the values
°f the longitudinal dispersivity and the ratio of longitudinal to transverse
dispersivities. With more than two polynomials an optimization approach is used
in arriving at the values. The methods converge to the true values for a good
initial estimate of the values.
77:02F-039
A MODIFIED OPTIMIZATION METHOD OF ESTIMATING AQUIFER PARAMETERS,
Navarro, A.
United Nations, Centre for Natural Resources, Energy, and Transport/Economic
and Social Affairs Department, Water Resources Branch, New York 10017.
Water Resources Research, Vol. 13, No. 6, p 935-939, December 1977. 3 tab,
15 ref, 11 equ.
Descriptors: Optimization, Aquifers, Groundwater, Groundwater movement, Ground-
water resources, Aquifer characteristics, Mathematical studies, Model studies.
A modified optimization method for estimating transmissivity and storativity
parameters has been utilized for the fast calibration of mathematical models of
transient aquifers. The method provides usable solutions at an intermediary
point between the minimization of residuals in the water budget equations and
the similitude of solutions to field estimations of parameters T and S. Four
field examples of the use of the method are given and discussed in terms of
relative accuracy of results.
77:02F-040
CHEMICAL DYNAMICS OF A CONFINED LIMESTONE AQUIFER,
LeFebre, V.
New Mexico Institute of Mining and Technology, Department of Physics, Socorro,
New Mexico.
Available from the National Technical Information Service, Springfield, Virginia
22161 as PB-265666, Price codes: A12 in paper copy, A01 in microfiche. New
Mexico Water Resources Research Institute, Las Cruces, WRRI Report No. 084, March
1977, 253 p, 16 fig, 4 tab, 6 ref, 3 append.
Descriptors: *Aquifer characteristics, *Groundwater, *Groundwater movement,
*New Mexico, Saline water intrusion, Physicochemical properties, Flow characteris-
tics. Time, Velocity, Limestone, Recharge, Dissolved oxygen, Ions, Artesian
aquifers.
The evolution of groundwater in the Roswell Limestone Aquifer is measured using
some ordinary and easily determined characteristics of the water. Randomness
caused by analytical error and matrix inhomogeneity is suppressed by dividing the
study area into subsections on the basis of hydrologic function and by using
averaged values of the measured characteristics to describe each subdivision.
Temperature, ionic solute concentrations, calcite saturation, and dissolved oxygen
content change in a reasonably steady and monotonic manner as the water flows from
the recharge to the discharge region. Simple models are developed to quantify the
oxygen and temperature measurements. On the basis of these models the groundwater
flow is found to be a factor of 6 faster in the northern part of the Roswell Lime-
stone Aquifer and the residence time is a factor of 3 longer in the southern part.
Solute concentrations indicate intrusion into the northeast corner of the Limestone
Aquifer from an upper Alluvium Aquifer. This study demonstrates that groundwater
evolves in a measurable manner as it flows through an aquifer. Both physical
(temperature) and chemical (oxygen content and calcite saturation) parameters change
in a predictable fashion.
25
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77:02F-041
IRRIGATION WASTEWATER DISPOSAL WELL STUDIESSNAKE PLAIN AQUIFER,
Graham, W.G., Clapp, D.W., and Putkey, T.A.
Idaho Department of Water Resources, Statehouse, Boise, Idaho 83720.
Publication No. EPA-600/3-77-071, June 1977. 51 p, 8 fig, 22 tab, 13 ref.
Descriptors: Runoff, Idaho, Irrigation, Irrigation effects, Aquifers, Water
quality.
Drain wells are used to dispose of excess irrigation and surface runoff water
from approximately 320,000 acres of agricultural land within the eastern Snake
River Plain area of southern Idaho. The impact of this practice on the under-
lying Snake River Plain aquifer, the primary source of potable water for approxi-
mately 140,000 people, was not understood. Thus, an investigation was initiated
to evaluate the impact of irrigation disposal well practices on the water quality
of the Snake Plain aquifer.
77:02F-042
NEBRASKA'S GROUND WATER MANAGEMENT ACT,
Axthelm, D.D.
Nebraska University, Department of Agricultural Engineering, Lincoln, Nebraska.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-5,
4 ref.
Descriptors: Nebraska, Groundwater, Groundwater resources, Law enforcement.
The Ground Water Management Act in Nebraska is becoming operational. It is being
put into effect in a deliberate and orderly manner by the Natural Resources
Districts of Nebraska as dictated by state statute.
77:02F-043
GROUNDWATER MANAGEMENT POLICIES: THE VIEWS OF THE PEOPLE,
Baird, F.L.
Texas Tech University, Department of Political Science, Lubbock, Texas.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 137-160, February 13-15, 1977. 1 fig, 14 tab, 29 ref.
Descriptors: Groundwater, Groundwater basins, Groundwater potential, Groundwater
resources, Texas, Irrigation, Urbanization.
The primary objective of this study was to measure the attitudes toward alterna-
tive public institutions for groundwater planning and management on the Texas High
Plains. More specifically, the objectives of this project were (1) To determine
the attitudes of irrigation farmers in the High Plains of Texas toward various
possible forms for the planning and management of groundwater, whether such regu-
lations be individual, local, state, national or some combination of these, (2)
To measure and analyze the attitudes of urban residents in a Standard Metropolitan
Statistical Area (SMSA) of the region toward the same topic, and (3) To measure
the attitudes of college students toward these.
77:02F-044
PRACTICAL GROUND WATER MANAGEMENT,
Axthelm, D.D.
Nebraska University, Department of Agricultural Engineering, Lincoln, Nebraska.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 168-172, February 13-15, 1977.
Descriptors: Groundwater, Irrigation, Groundwater resources, Groundwater recharge,
Groundwater mining, Groundwater basins, Nebraska, Natural resources, Resources.
The emphasis on groundwater development for irrigation lasted about a century.
Concern has now shifted from development to management of the groundwater resources.
This emphasis will continue indefinitely. There is a current need to develop
practical management methods and techniques.
26
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77:02F-045
STEADY STATE BI-LEVEL SUBSURFACE DRAINAGE THEORY FOR SOILS OF VARYING HYDRAULIC
CONDUCTIVITY,
Acharya, H.S.
Marathwada Agricultural University, Department of Agricultural Engineering,
Parbhani (India).
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 2,
p 276-277, March-April, 1977. 3 fig, 1 tab, 4 ref.
Descriptors: *Drainage, *Hydraulic conductivity, *Water table, *Model studies,
Mathematical models, Tile drainage, Equations, Subsurface drainage, Groundwater,
Groundwater movement, Hydrology.
In practice, various situations exist where hydraulic conductivity varies with
depth. Soils with varying clay percentage, with varying stone content, or with
layers of different types of soils form a few examples of such situations. The
aim of this article was to study the steady-state bi-level subsurface drainage
problem for soils with varying hydraulic conductivity. Cases of constant hydraulic
conductivity follow as special cases of the analysis.
77:02F-046
ESTIMATION OF AQUIFER DIFFUSIVITY IN STREAM-AQUIFER SYSTEMS,
Singh, S.R., and Sagar, B.
Punjab Agricultural University, Department of Soil and Water Engineering, Lud-
hiana (India).
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY11, Proceedings Paper 13362, p 1293-1302, November 1977. 1 fig, 2 tab,
18 ref.
Descriptors: *Diffusivity, *Aquifers, *Groundwater, *Mathematical models, *Streams,
Equations, Hydrographs, Model studies, Aquifer characteristics. Water levels,
Hydraulic gradient.
By specifying an extra boundary condition in terms of hydraulic gradient at the
stream-aquifer interface and by using the Green's function of the linearized
Boussinesq equation, analytical solutions were developed to determine aquifer dif-
fusivity explicitly. Four different types of Dirichlet boundary condition descri-
bing stream gage hydrographs were employed. They were: (1) linearly rising water
level in the stream; (2) exponentially rising water level in the stream; (3) water
level represented by a sinusoid; and (4) hydrographs approximated by cubic splines.
The last one is quite general and is capable of analyzing different shapes of
smooth stream hydrographs expected to occur in nature. Hydraulic gradient at the
interface was computed using splines. The solutions were validated by analyzing
the stream-aquifer data observed in a sand tank model. They yielded consistent
values of the aquifer diffusivity at different times and, therefore, are useful
in determining the parameter of the aquifers contiguous to streams.
77:02F-047
UNSTEADY FLOW TO A PUMPED WELL IN A FISSURED WATER-BEARING FORMATION,
Boulton, M.S., and Streltsova, T.D.
Sheffield University, Department of Civil and Structural Engineering, (England).
Journal of Hydrology, Vol. 35, No. 3/4, p 257-269, November 1977. 9 fig, 3 ref.
Descriptors: *Unsteady flow, *Groundwater movement, *Mathematical models, *Fissures
(geologic), *Water wells, Equations, Drawdown, Compressibility, Permeability,
Curves, Hydraulic properties, Porosity, Aquifer characteristics, Pumping, Dis-
charge (water), Flow.
New equations were derived for the drawdown in a water-bearing fissured rock for-
mation, consisting of a set of horizontal low-permeability porous blocks separated
by highly permeable fissures. Porous blocks and fissures were assumed to be com-
pressible. The depth of the fissure is small compared with that of the block.
The abstraction well, lined along the block, is pumped at a constant rate. The
discharge per unit length of the unlined part in the fissure is constant, and the
radius of the well is vanishingly small. Type curves for the drawdown in the
fissure and the porous block were computed and plotted for some selected para-
meters involved. Procedure for determining the fissured aquifer parameter con-
stants was outlined.
27
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77:02F-048
UNSTEADY FLOW TO A PUMPED WELL IN A TWO-LAYERED WATER-BEARING FORMATION,
Boulton, N.S., and Streltsova, T.D.
Sheffield University, Department of Civil and Structural Engineering, (England).
Journal of Hydrology, Vol. 35, No. 3/4, p 245-256, November 1977. 5 fig, 1 ref.
Descriptors: *Unsteady flow, *Groundwater movement, *Mathematical models, *Water
wells, Equations, Drawdown, Fissures (geologic), Discharge (water), Curves, Pumping,
Compressibility, Hydraulic properties, Aquifer characteristics.
New equations were derived for the drawdown in an aquifer, consisting of two
horizontal layers, referred to as the block and the fissure, which have different
hydraulic properties. The block and the fissure are compressible. Account was
taken of both the horizontal and vertical flow components in the block and the
fissure. The depth of the fissure was assumed to be small compared with that of
the block. The abstraction well, which is pumped at a constant rate, has a van-
ishingly small radius. Type curves for drawdown in the fissure and the block were
computed and plotted for some values of the aquifer constants involved.
77:02F-049
THE KINETICS OF MINERAL DISSOLUTION IN CARBONATE AQUIFERS AS A TOOL FOR HYDRO-
LOGICAL INVESTIGATIONS, II. HYDROGEOCHEMICAL MODELS,
Mercado, A.
Tahal-Water Planning for Israel Ltd., Tel Aviv.
Journal of Hydrology, Vol. 35, No. 3/4, p 365-384, November 1977. 10 fig, 13 ref.
Descriptors: *Dissolved solids, *Mineral water, *Transmissivity, *New Mexico,
Model studies, Mathematical models. Aquifers, Limestones, Hydrology, Water quality,
Chemicals, Water chemistry, Groundwater, Groundwater movement, Spatial distribu-
tion, Hydraulic conductivity, Permeability, Recharge, Rainfall.
A general differential equation, describing the dissolution of minerals and the
transport of their products in porous media, was derived and simplified for the
case of steady-state, nonequilibrium distribution of solutes in confined carbonate
aquifers. The numerical solution of the equation, 'which represents the hydrogeo-
chemical model of a given aquifer, was based on the transformation of aquifer
space coordinates into time coordinates of "tracing points" moving along ground-
water streamlines, followed by an inverse transformation which yields theoretical
water quality maps. The applicability of the model for integrating hydrologic
and geochemical data in aquifers was demonstrated for the limestone aquifer of
Roswell, New Mexico.
77:02F-050
NONLINEAR DIFFUSION APPLIED TO GROUNDWATER CONTAMINATION PROBLEMS,
Basak, P., and Murty, V.V.N.
Punjab Agricultural University, Department of Civil Engineering, Ludhiana. India,
Journal of Hydrology, Vol. 35, No. 3/4, p 357-363, November 1977. 5 fig, 5 ref.
Descriptors: Mathematical studies, Diffusion, Groundwater, Groundwater movement,
Groundwater resources, Aquifers, Water quality, Water pollution.
An analytical solution to the problem of concentration dependent diffusion with in^
creasing concentration at the source is presented. The solution is of traveling
wave type and is applied to predict the contamination in an aquifer from a source
wherein the contamination concentration is increasing with time,
77:02F-051
PUMP TESTING IN HETEROGENEOUS AQUIFERS,
Vandenberg, A.
Inland Waters Directorate, Environment Canada, Ottawa, Ontario, Canada.
Journal of Hydrology, Vol. 34, No. 1/2, p 45-62, July 1977. 12 fig, 1 tab, 11 ref.
23
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Descriptors: Model studies, Aquifers, Groundwater, Groundwater resources,
Simulation analysis, Pump testing, Pumping plants, Pumps, Transmissivity.
A finite-difference model of an infinite horizontal nonleaky aquifer was used
to simulate a constant-rate pump test in a heterogeneous aquifer; the values
of transmissivity specified for the nodes of the finite-difference grid were
chosen at random from a uniform distribution over the interval 0-0.1 m sq/min
and the_ratio transmissivity/storativity was kept constant. The spacing of
the finite-difference grid was 10 m in the vicinity of the pumped well at the
center of the grid and became progressively wider towards the boundaries of
the square area. The boundaries were located at a distance of 23 km from
the well.
77:02F-052
NON-DARCY FLOW AND ITS IMPLICATIONS TO SEEPAGE PROBLEMS,
Basak, P-
Punjab Agricultural University, Department of Civil Engineering, Luhiana (India)
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR4, Proceedings Paper 13442, p 459-473, December 1977.
9 fig, 4 tab, 44 ref.
Descriptors: *Drainage, *Seepage, *Darcys law, Drainage systems, Porous media,
Confined water, Analytical techniques, Hydraulics, Equations, Flow, Discharge
(water).
Analytical solutions for the problems of drainage spacing in a ditch drainage
system and steady-state seepage through confined aquifer of variable thickness
incorporating Izbash's nonlinear velocity-gradient response v = M times i to
the nth power were presented. The effect on nonlinearity in the flow response
on the drainage spacing, discharge characteristics, and piezometric pressure
distribution in relation to the corresponding Darcian linear case was brought
out. The solutions derived showed that nonrecognition of even a weak non-
Darcy flow would lead either to an uneconomical or an unsafe (depending on
the value of non-Darcy parameter n) drainage spacing for ditch drainage pro-
blems and would lead to considerable over or under prediction of discharge for
confined aquifer problem. Apart from the previously mentioned analytical
solutions, a perspective view of non-Darcy flow through porous media was in-
corporated, and its importance in various drainage projects was examined.
29
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SECTION VI
WATER CYCLE
WATER IN SOILS (GROUP 02G)
77-.02G-001
A COMPARISON OF IN SITU EXTRACTORS FOR SAMPLING SOIL WATER,
Levin, M.J., and Jackson, D.R.
Oak Ridge National Laboratory, Environmental Sciences Division, Tennessee.
Soil Science Society of America Journal, Vol. 41, No. 3, p 535-536, May-June,
1977. 1 fig, 1 tab, 3 ref.
Descriptors: *Soil water, *Sampling, *Aqueous solutions, Solvents, Lysimeters,
Tensiometers, Laboratory tests. Evaluation, Equipment, Leaching, Leachate, Soil
science.
Comparisons were made between two in situ extractors for collection of soil water
samples: Amicon hollow fibers and porous ceramic cup lysimeters. Intact soil
cores removed from a fescue pasture were fitted with lysimeters and fibers at 10
and 20 cm depth. Cores were leached by adding increments of water in excess of
field capacity weekly. After drainage, soil solutions were extracted using
lysimeters and fibers. Concentrations of Ca and Mg in soil solutions were greater
at 10-cm than at 20-cm soil depths. Neither extractor altered the concentrations
of Ca, Mg, or P04-P during collection. The studies suggest that lysimeters and
hollow fibers are viable devices for extracting of soil water samples. Porous
ceramic cup lysimeters are preferable for field plots, while hollow fibers are
advantageous for intact soil cores. A major advantage of the hollow fiber tech-
nique is the small soil displacement required for installation.
77:02G-002
EXPERIMENTAL STUDIES OF WETTING FRONT INSTABILITY INDUCED BY GRADUAL CHANGE OF
PRESSURE GRADIENT AND BY HETEROGENEOUS POROUS MEDIA,
White, I., Colombera, P.M., and Philip, J.R.
Commonwealth Scientific and Industrial Research Organization, Division of En-
vironmental Mechanics, Canberra (Australia).
Soil Science Society of America Journal, Vol. 41, No, 3, p 483-489, May-June,
1977. 7 fig, 3 tab, 15 ref.
Descriptors: *Infiltration, *Porous media, *Laboratory tests, Soil water, Soil
water movement. Model studies, Mathematical models, Soils, Pressure, Hydraulic
conductivity, Soil science, Soil physics.
The stability of infiltration flows in Hele-Shaw cells was examined. Flows were
perturbed either by gradually increasing G, the pressure gradient behind the wet-
ting front, or by heterogeneities in the cells. Two methods were used to increase
G gradually through zero: (1) by allowing the air ahead of the front to be com-
pressed by the flow, and (2) by monotonically increasing the hydraulic conductivity
of the cell with depth. In the other class of experiments, the flow was instan-
taneously perturbed by a step-increase in conductivity at selected depths. It was
found that Philip's stability analysis adequately predicted both the onset of in-
stability and the wavelength of the initial disturbances. For quadratic increase
in conductivity with depth, the observed growth rate of disturbances was faster
than expected from the linear theory. Examination of the data of Peck and of
Hill and Parlange showed that Philip's analysis is also adequate for coarse sands.
77:02G-003
MODEL CALCULATIONS FOR THE EXTRACTION OF SOIL WATER BY CERAMIC CUPS AND PLATES,
van der Ploeg, R.R., and Beese, F.
Institute of Soil Science and Forest Nutrition, Goettingen (West Germany),
30
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Soil Science Society of America Journal, Vol. 41, No. 3, p 466-470, May-June, 1977.
5 fig, 2 tab, 20 ref.
Descriptors: *Soil water, *Soil water movement, *0n-site investigations, Percola-
tion, Unsaturated flow. Seepage, Sampling, Soil moisture, Model studies, Mathemati-
cal models, Soils, Soil science, Soil physics.
A numerical method was developed with which the flow of moisture towards suction
units in soil can be evaluated. For a number of selected problems, the unsaturated
moisture flow_equation was solved twice: (1) for radial flow towards a suction
plate or suction cup; and (2) for vertical downwards flow under the same conditions,
but without a suction unit in the soil. The calculations were performed for a flat
soil without a plant cover. It was found that even for little vacuum, large dif-
ferences may exist between the seepage rate as determined from a suction unit as
compared to the seepage rate of the unextracted soil. It was shown also that the
radius of influence of a suction unit, which extracts water continuously, can be
several feet wide. It was concluded that in order to be reliable, data collected
with suction units should be analyzed with care.
77:02G-004
WATER AND SALT FLOW THROUGH COMPACTED CLAYS: I. PERMEABILITY OF COMPACTED ILLITE
AND MONTMORILLONITE,
Rolfe, P.F., and Aylmore, L.A.G.
Western Australia University, Extension Service, Nedlands.
Soil Science Society of America Journal, Vol. 41, No. 3, p 489-495, May-June,
1977. 4 fig, 3 tab, 47 ref.
Descriptors: *Permeabllity, *Clays, *Salts, Laboratory tests, Montmorillonite,
Illite, Chlorides, Cations, Pressure, Soil water movement, Solutions, Sodium
chloride, Cesium, Calcium chloride. Chemistry, Soil water, Soil science.
Studies have been made of the pressure-induced flow of the chloride solutions of
various monovalent, divalent and trivalent cations, at various concentrations,
through compressed Wyoming bentonite and Willalooka illite cores. The majority
of the measurements were carried out on the Willalooka illite core, and its per-
meability has been shown to depend markedly on the nature and concentration of
the cations present, with three- to fourfold variations being observed in some
instances. At the lower electrolyte concentrations, permeability increases in
the order Na less than Ca less than Ba less than La less than Cs at a given con-
centration. In addition, the permeability increases linearly with flow pressure
to an extent ranging from some 15% for the Na systems to 97% for the 3.0 M LaC13
system over the pressure range examined. The contributions to the permeability
changes arising from mechanical expansion of the flow cell, particle rearrange-
ments and the etectroviscous effect have been shown to be quite inadequate to ac-
count for the major changes observed. It was suggested that the most significant
effects arise as a result of the influence of cationic size, charge, and concen-
tration of the vicosity of the several layers of coerced water which form adjacent
to the clay surfaces. Coercion of water may arise partly through its association
with the exchangeable cations adsorbed on the surface or forming diffuse double
layers, but mainly from the preferred or unique water structure developed in
proximity to the clay surface. In particular, increasing concentrations of Cs,
Ca and La cations appear to cause a pronounced breakdown in water structure within
the pores.
77:02G-005
FALL SOIL WATER: EFFECT ON SUMMER SOIL TEMPERATURE,
Willis, W.O., Wierenga, P.J., and Vredenburg, R.T.
Agricultural Research Service, Fort Collins, Colorado.
Soil Science Society of America Journal, Vol. 41, No. 3, p 615-617, May-June, 1977.
5 fig, 10 ref.
Descriptors: *Soil temperature, *Soil water, *Effacts, *North Dakota, Soil mois-
ture, Crops, Wheat, On-site investigations, Model studies, Mathematical models,
Forecasting, Analytical techniques, Soil properties, Thermal properties, Soil-
water-plant relationships, Soil investigations, Soil science, Agriculture.
31
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Soil temperature with depth (to 150-cm) and time (April through September) was
measured in field plots in North Dakota to determine the effect of three depths
of wetting in late fall before freezing on the growing season soil temperature _
the following year. All plots were planted with spring wheat and received identi-
cal treatment during the growing season. The data indicated that a high soil
water content in the fall may cause soil temperature in the 30- to 120-cm depth
to be 1 to 2 C lower than normal during the next year's growing season, particu-
larly if that season has lower-than-normal precipitation. By using soil temp-_
erature values from the 15-cm and 120-cm depths as the upper and lower boundaries,
calculated soil temperatures agreed better with measured values than when 0.2-
cm and 120-cm depths were used as boundaries.
77:02G-006
EVALUATION OF THEORETICALLY PREDICTED THERMAL CONDUCTIVITIES OF SOILS UNDER FIELD
AND LABORATORY CONDITIONS,
Hadas, A.
Agricultural Research Organization, Institute of Soil and Water, Bet-Dagan (Israel) .
Soil Science Society of America Journal, Vol. 41, No. 3, p 460-466, May-June,
1977. 7 fig, 18 ref.
Descriptors: *Soil water movement, *Heat transfer, *Water vapor, Soil moisture.
Soil water, Soil temperature, Irrigation, Irrigation effects, Thermal conductivity,
Model studies, On-site investigations, Laboratory tests, Soil physics, Agriculture,
Soil science.
In the literature one finds claims that the Philip-deVries model of heat and mois-
ture transfer fails to predict the amounts of water moved by vapor transfer. In
the work reported here, an attempt was made to check and to verify the predictive
capabilities of the deVries, Philip and deVries models for vapor transfer by eval-
uating the latent heat transfer carried by vapor rather than to account for vapor
flow from the usually performed total moisture balance. It was found that the
deVries model predicts accurately the transfer of heat by vapor under steady-state
conditions, but the model underestimates transfer of heat under nonsteady-state
conditions. The possibility that the assumed diffusive Vapor transport should be
corrected by including "enhancement factors" so as to incorporate local thermal
gradients and mass movement induced vapor transfer, not accounted by the present
model, was brought up; and the nature of the enhancement factors and the impli-
cations to field conditions were discussed.
77:020-007
DIURNAL SOIL WATER REGIME IN THE TILLED PLOW LAYER OF A WARM, HUMID CLIMATE,
Bruce, R.R., Thomas, A.W., Harper, L.A., and Leonard, R,A,
Southern Piedmont Conservation Research Center, Watkinsville, Georgia.
Soil Science Society of America Journal, Vol. 41, No. 3, p 455-460, May-June,
1977. 12 fig, 1 tab, 14 ref.
Descriptors: *Soil water, *Diurnal, Cultivation, *Humid climates, Depth, Soil
temperature, Air temperature, Wind velocity, Vapor pressure, Water vapor, On-
site investigations, Humid areas.
The soil water content in 10 depth intervals in the surface 15 cm of soil was deter-
mined hourly for 9 days in June at 83 deg 25 min W, 33 deg 52 min N, Over the
same period at 15-min intervals, soil temperatures were measured at eight depths,
wind-speed and air temperatures at six elevations, atmospheric water vapor pres-
sures at three elevations, incident solar and net radiation at one meter. From
the microclimate data, flux of water vapor at the soil surface was calculated,
which was then used to compute soil water flux at several depths by using soil
water content data. The diurnal soil water content and soil water flux patterns
were compared for a dry period before a rainfall event and afterward. Dramatic
diurnal variation of the soil water content at depths less than 2 cm was observed.
The variation during periods of no rain is related to daily radiation inputs at
the soil surface, which generated the observed temperature and soil water gradients
responsible for soil water redistribution. Occurrence of rainfall and infiltration
events during the measurement period showed additional dynamics of the field sy-
stem. Descriptions of the diurnal soil water dynamics in the plow-layer provide
a basis for examining soil processes dependent upon soil water regime.
32
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77:02G-008
AUTOMATIC FEEDBACK CONTROL TO MAINTAIN CONSTANT SOIL MOISTURE TENSION IN THE
STUDY OF DROUGHT TOLERANCE IN RJ.CE ,
Alvarez, E.I., and De Datta, S.K.
International Rice Research Institute, Department of Agronomy, Los Banos, Laguna
(Philippines).
Soil Science Society of America Journal, Vol. 41, No. 3, p 452-454, May-June,
1977. 3 fig, 2 tab, 9 ref,
Descriptors: *Moisture tension, *Soil moisture, *Rice, *Soil-water-plant rela-
tionships, Greenhouses, Evapotranspiration, Laboratory equipment, Moisture stress,.
Perlite, Osmotic pressure, Tensiometers, Analytical techniques.
A greenhouse technique was developed by which a chosen soil moisture tension can
be maintained continuously. The setup for supply water at relatively constant
soil moisture tension in pots includes five major components: water tank, W-
tube, water distribution system, soil moisture tension sensors, and pots. The
W-tube, which contains a predetermined amount of Hg, controls the soil moisture
tension in the pots. Water can flow freely from the tank to the pots through
the distribution system whenever the soil moisture tension exceeds that desired.
Response to the sensors' demand for water is rapid. This setup was used success-
fully to compare relative drought tolerance of rice varieties and breeding lines.
Another use of the setup might be to measure evapotranspiration (ET) almost in-
stantaneously; the technique might be useful in some soil-plant-atmosphere-
water relationship studies.
77:02G-009
EXPERIMENTAL TEST OF THE LANGEVIN EQUATION AS A MODEL FOR WATER FLOW THROUGH
UNSATURATED SOIL,
Sposito, G., Sullivan, P-, and Gupta, V.
California University, Department of Soil Science and Agricultural Engineering,
Riverside, California.
Soil Science Society of America Journal, Vol. 41, p 820-822, 1977. 2 fig, 19 ref,
8 equ.
Descriptors: *Model studies, *Unsaturated flow, *Soil water movement, *Hydraulic
conductivity, *Diffusivity, Equations, Soil moisture.
The parameters that appear in the Langevin Equation, a molecular model for the
flow of water through soil, are expressed as functions of the hydraulic conducti-
vity, the water diffusivity, and the soil water matric potential. This permits
the parameters to be calculated using available data on the transport properties
of homogeneous, unsaturated soils. Since the parameters must have values lying
within certain ranges in order that the Langevin Equation and the Markovian
hypothesis on water flow that comes from it be applicable, it is possible to test
the equation and the hypothesis experimentally. The results for 15 different
soils shows that: (1) the equation and the Markovian hypothesis are consistent
with soil water data for homogeneous, unsaturated soils throughout the normal
field range of water content and (2) the molecular parameters in the Langevin
Equation show the same behavior for a wide variety of soils when they are ex-
pressed as functions of the matric potential.
77:026-010
INFLUENCE OF SOIL PROPERTIES, LEACHING FRACTION, AND PLANT WATER UPTAKE ON SOLUTE
CONCENTRATION DISTRIBUTION,
Jury, W.A., Fluhler, H., and Stolzy, L.H.
California University, Department of Soil Science and Agricultural Engineering,
Riverside, California.
Water Resources Research, Vol. 13, No. 3, p 645-650, June 1977. 9 fig, 1 tab,
19 ref.
Descriptors: *Leaching, *Soil water movement, *Soil properties, laboratory
tests, Moisture content, Lysimeters, Solutes, Soil water, Water quality, Soil
moisture, Model studies, Mathematical models, Simulation analysis, Profiles,
Distribution patterns, Soils, Hydraulic conductivity. Clay loam, Loam, Water
balance.
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Studies of salt movement through 24 cropped lysimeters receiving high-salinity
irrigation were reported. A great deal of variability was found between depth-
equivalent salinity sensor readings during the experiment, both between different
lysimeters receiving the same water and salt inputs and among lateral replicates
within each lysimeter. A computer simulation of the first 75 days of the experi-
ment, using the measured soil properties and external inputs, alternately varied
the hydraulic conductivity-water content relation, the irrigation flux, and the
water uptake distribution by an amount consistent with the uncertainty in their
measurement to see the effect on solute concentrations. It was found that large
variations in the conductivity-water content relations and 10% uncertainty in
the input flux had little effect on solute concentrations, but that variations
in the water uptake patterns within the top 60 cm created a large distribution
of concentrations at a given depth and time.
77:02G-011
ESTIMATING THE EFFECTIVE CAPILLARY PRESSURE IN THE GREEN AND AMPT INFILTRATION
EQUATION,
Brakensiek, D.L.
Agricultural Research Service, Northwest Watershed Research Center, Boise, Idaho.
Water Resources Research, Vol. 13, No. 3, p 680-682, June 1977. 1 fig, 1 tab,
7 ref.
Descriptors: *Infiltration, *Mathematical models, *Pore pressure, *Capillary
water, Capillary conductivity, Model studies, Loam, Moisture content, Soils,
Pressure, Groundwater movement, Wetting, Estimating.
A considerable amount of research indicates that the Green and Ampt infiltration
equation can be used in hydrologic modeling with confidence. The parameters,
however, still require considerable field and/or laboratory effort to determine
estimated values. Reported were alternatives for determining the average wetting
front capillary pressure parameter. Only a moisture-characteristic would be
required.
77:026-012
MASS TRANSFER STUDIES IN SORBIN POROUS MEDIA; II. EXPERIMENTAL EVALUATION WITH
TRITIUM (3H20) ,
van Genuchten, M.T., and Wierenga, P.J.
New Mexico State University, Department of Agronomy, University Park, New Mexico.
Soil Science Society of America Journal, Vol. 41, No. 2, p 272-278, March-April,
1977. 6 fig, 3 tab, 21 ref, 1 append.
Descriptors: *Tritium, *Mass transfer, *Porous media, *Sorption, Diffusion,
Curves, Adsorption, Soil aggregates, Unsaturated flow, Mathematical models,
Clay loam, Laboratory tests, Equations,
A comparison was made between observed tritium effluent concentration distributions
and those calculated with a previously published analytical solution for the move-
ment of chemicals through unsaturated, aggregated sorbin media. In the analytical
model, the liquid phase of the soil was divided into mobile and immobile regions,
with transfer between the two regions diffusion controlled. Effluent data ob-
tained from several displacements of tritium through a 30-cm long columns of
Glendale clay loam were used to determine the different parameters in the analyti-
cal solution by curve fitting. The data indicated some adsorption or isotopic
exchange of tritium during its flow through the soil columns. The amount of im-
mobile water increases with decreasing flow velocity and increasing aggregate size,
and varies between 6 and 45% of the total volume of water in the columns. The
analytical solution provided an excellent description of the experimental effluent
data, and showed that tailing can be explained satisfactorily by diffusional ex-
change of tritium between mobile and immobile regions of the soil.
77 :O2G-013
MASS TRANSFER STUDIES IN SORBING POROUS MEDIA: III. EXPERIMENTAL EVALUATION WITH
2, 4, 5-T,
van Genuchten, M.T., Wierenga, P.J., and O'Connor, G.A.
New Mexico State University, Department of Agronomy, University Park, New Mexico.
Soil Science Society of America Journal, Vol. 41, No. 2, p 278-285, March-April,
1977. 6 fig, 3 tab, 16 ref,
-------
Descriptors: *Mass transfer, *Sorption, *Porous media, Diffusion, Adsorption,
Unsaturated flow, Hysteresis, Soil aggregates, Clay loam, Laboratory tests,
Curves, Mathematical models.
Comparisons were made between observed and calculated effluent concentration
distribution for the movement of 2, 4, 5-T (2,4,5-trichlorophenoxyacetic acid)
through 30-cm long unsaturated soil columns. The comparisons were made using
both analytical and numerical solutions of a previously published model, which
included the effects of intra-aggregate diffusion and adsorption. The results
in this study indicated that intra-aggregate diffusion and adsorption/desorption
are the main mechanisms responsible for effluent tailing. An estimated 60% of
the adsorption was found to occur in the stagnant region of the soil. When in-
tra-aggregate diffusion was included in the model, the observed adsorption/de-
sorption hysteresis phenomenon found to be significant in several earlier
studies was shown to be much less important in describing the observed concen-
tration distributions.
77:02G-014
MODELING SOIL WATER HYDROLOGY UNDER A POST OAK (QUERCUS STELLATA WANGENE) -
SHORTLEAF PINE (PINUS ECHINATA MILL.) STAND IN EAST TEXAS,
England, C.B.
Agricultural Research Center, Hydrograph Laboratory, Beltsville, Maryland.
Water Resources Research, Vol. 13, No. 3, p 683-686, June 1977, 3 fig, 1 tab,
20 ref.
Descriptors: *Soil water, *Model studies, *Forest watersheds, *Texas, Computer
models, Mathematical models, Soil water movement, Oak trees, Pine trees, Hydrology,
Hydrologic aspects, Hydrologic systems, Infiltration, Evapotranspiration,
Watersheds (basins), On-site investigations.
A digital model of watershed hydrology successfully computed daily soil water
contents of the two upper layers in a Boswell soil under an east Texas post oak -
shortleaf pine stand throughout 4 years (1957-1960). The experiment demonstrated
the fidelity of the model components to the prototype system elements. In ad-
dition, the experiment provided parameters useful in applying the model for
elucidating the hydrology of watersheds containing oak-pine forests,
77:020-015
MODEL OF SALT FLOW IN SOIL WITH A SOURCE-SINK TERM,
Melamed, D., Hanks, R.J., and Willardson, L.S.
Utah State University, Department of Soil Science, Logan, Utah.
Soil Science Society of America Journal, Vol. 41, No. 1, p 29-33, January-February,
1977. 4 fig, 12 ref.
Descriptors: *Saline soils, Irrigation, *Salts, *Model studies, Mathematical
models, Laboratory tests, On-site investigations, Soil properties, Salinity,
Electrical conductance, Conductivity, Soil chemical properties, Effluents, Chemical
precipitation, Leaching, Soil science, Path of pollutants.
Irrigation management practices require a knowledge of the salinity in the root
zone. Models which simulate the simultaneous movement of water and soils but
ignore the buffering property of the soil fail to predict the root zone salinity
distribution in many field situations. A model was developed that takes into
consideration source and sink processes. It was tested under laboratory and field
situations. In determining a "source-sink" term to be included in the model, it
was assumed that precipitation and dissolution were the most important source pro-
cesses and that the rate of the processes was a function of the surrounding con-
centration. The parameters for the "sink-source" term for soil columns were^de-
termined from effluent data and were found suitable for predicting the salinity
of the entire soil column. Under field conditions, individual parameters for
each layer were needed for good prediction.
77:026-016
FRITTED GLASS BEAD MATERIALS AS TENSIOMETERS AND TENSION PLATES,
Chow, T.L.
Newfoundland Forest Research Centre, St. John's, Newfoundland.
35
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Soil Science Society of America Journal, Vol. 41, No. 1, p 19-22, January-February,
1977. 1 fig, 3 tab, 5 ref.
Descriptors: *Tensiometers, *Moisture tension, * Instrumentation, Materials, Porous
media, Particle size, Hydraulic conductivity, Saturated flow,_Laboratory tests,
Materials testing. Materials engineering, Soil water, Soil science.
A maximum temperature of 655 C, which was reached in six steps with approximately
100 C/step/hour for 90 min. was used to frit glass beads. Tensiometer or tension
plate with desired dimension and operational characteristics can be constructed
from the product. Uniformity tests on the product indicate negligible_horizontal^
temperature variations during the fritting process, and slow heat dissipation^during
the cooling phase tends to limit its thickness. Tests on the particle size dis-
tributions suggest that glass beads graded to a very narrow distribution are re-
quired to produce fritted material with both the maximum saturated hydraulic con-
ductivity and maximum air-entry value.
77:02G-017
PREDICTIONS OF THE SOIL WATER FLUX BASED UPON FIELD-MEASURED SOIL-WATER PROPERTIES,
Warrick, A.W., Mullen, G.J., and Nielsen, D.R,
Arizona University, Tucson, Arizona.
Soil Science Society of America Journal, Vol. 41, No. 1, p 14-19, January-February,
1977. 5 fig, 4 tab, 12 ref.
Descriptors: *Soil water movement, Variability, *Soil properties. Soil water,
On-site investigations, Sampling, Hydraulic conductivity, Mathematical models,
Spatial distribution, Moisture content, Soils, Clay loam, Monte Carlo method,
Infiltration, Soil science.
Predictions of soil water flux are made taking into account spatial variability
of the soil water parameters. A conductivity of the form K = K sub 0 exp (alpha
(theta-theta sub 0)) is utilized where theta is the volumetric water content with
K sub 0 and theta sub 0 the values of hydraulic conductivity and water content for
steady-state intake from water ponded on the soil surface. The value of alpha is
an empirical constant for each site and for each depth. -Monte Carlo simulations
were used to simulate the flux distribution from the simplified drainage equation
J sub L = K sub 0/(1 + alpha K sub 0 t/L). The flux of J sub L is a random out-
put dependent upon the stochastic nature of K sub 0 and alpha. Log-normal dis-
tributions of K sub 0 and alpha are chosen from field data published for Panoche
soil. Output of J sub L is approximately log-normal for all times studied. The
mean value of J sub L in larger than the flux calculated using the average K sub
0 and alpha values in the above equation. Sample numbers necessary to estimate
the means of the flux at t = 0, 1, and 10 days were plotted. For t = 0,
of 1,000, 100, and 50 result in estimates of J sub L within 16, 50, and
samples
of
For
t = 1 and 10 days similar figures for sam-
Values of water content stored
the true mean 95% of the time.
pies of 1,000, 100, and 50 are 4, 14, and
in the profile using the above equations also were examined as a random function.
Unlike the flux values, the range in values stays about the same for at least 20
days. The research points out a need for meaningful methods for sample stratifi-
cation in order to reduce variances.
77:02G-018
SOLUTE MOVEMENT IN A FIELD SOIL,
Van De Pol, R.M., Wierenga, P.J., and Nielsen, D.R.
New Mexico State University, Department of Agronomy, Las Cruces, New Mexico.
Soil Science Society of America Journal, Vol. 41, No. 1, p 10-13, January-February,
1977. 5 fig, 8 ref.
Descriptors: *Soil water movement, *Solutes, *Subsurface flow, On-site investi-
gations, Soils, Porous media, Infiltration, Adsorption, Leaching, Dispersion,
Variability, Spatial distribution, Tracers, Tritium, Chlorides, Pore water, Soil
water, Agriculture, Soil science, Path of pollutants.
Solute and water movement was studied under steady-state flow conditions in a
field soil consisting of 70 cm of clay to silty clay over a medium sand. A
steady-state water flow condition was maintained by applying irrigation water at
36
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a constant flux of 2 cm per day. During the steady-state conditions, some of the
water leached into the plot was labelled with chloride and tritium. The positions
of the chloride and tritium as functions of soil depth and time were measured by
extracting samples of the soil solution with soil suction probes. Extremes in
solute displacement occurred at equal and different depths within the plot. An
analysis of these measurements indicated that observations of the pore water
velocity and the apparent diffusion coefficient were log normally distributed.
Twenty-four soil suction probes, used to identify the rate at which a solute was
displaced in the soil, will yield an estimate of the mean pore water velocity
of this soil within a range of approximately plus or minus 25% of its true value,
providing that the effects of potential solute-soil interactions are taken into
account.
77:020-019
ON SOLVING THE NONLINEAR DIFFUSION EQUATION: A COMPARISON OF PERTURBATION,
ITERATIVE, AND OPTIMAL TECHNIQUES FOR AN ARBITRARY DIFFUSIVITY,
Parlange, J.Y., and Babu, O.K.
Connecticut Agricultural Experiment Station, New Haven, Connecticut.
Water Resources Research, Vol. 13, No. 1, p 213-214, February 1977. 9 ref.
Descriptors: *Soil water movement, *Filtration, *Diffusion, *Diffusivity,
Mathematical models, Equations, Mathematics, Analytical techniques, Soil water,
Optimization.
A recent solution determined by Babu for an arbitrary soil-water diffusivity was
compared with two earlier solutions. It was shown that the perturbation solu-
tion is identical to the iterative result when Cister's correction is used. It
was also shown that a result obtained by optimization, which is numerically in-
distinguishable from either the perturbation or iterative result, has a much
simpler analytical form.
77:020-020
SOIL WATER REGIMES NEAR POROUS CUP WATER SAMPLERS,
Warrick, A.W., and Amoozegar-Fard, A.
Arizona University, Department of Soils, Water, and Engineering, Tucson, Arizona.
Water Resources Research, Vol. 13, No. 1, p 203-207, February 1977. 4 fig, 1
tab, 14 ref, 1 append.
Descriptors: *Soil water movement, *Unsaturated flow, *Mathematical studies,
Soil water,- Equations.
Steady soil water regimes near a porous cup water sampler were studied. Results
are applicable when one is sampling soil solutions in the field or laboratory,
and they help establish guidelines with respect to the sampling volume and region
of influence. The unsaturated hydraulic conductivity is taken as K = (K sub o)
exp (alpha x h), where K sub o and alpha are constants. The flow net was examined
for both point and horizontal line sinks for an infinite medium around the cup.
Analytical solutions for the potential and the stream functions were given for
the point sink. The maximum radial distance for which flow can be intercepted is
the square root of (q/pi x K sub o) exp (-alpha x h sub 1), where h sub 1 is the
pressure head at large distances and q the extraction rate. An alternative form
was found by expressing q in terms of the cup radius and tension. For the line
sink, an analytical solution was given for the potential, but the stream function
required a numerical integration. The maximum distance of influence is (q/2 K
sub o) exp (-a x h sub 1), where q is the flow rate per unit length. For both
point and line sinks, q increases with h sub 1. Also, q at first increases with
the suction in the cup (-h sub o), but it approaches a constant value.
77:02G-021
CONVECTIVE-DISPERSIVE SOLUTE TRANSPORT WITH A COMBINED EQUILIBRIUM AND KINETIC
ADSORPTION MODEL,
Cameron, D.R., and Klute, A.
Soil Research Institute, Department of Agriculture, Edmonton (Alberta), Canada,
Water Resources Research, Vol. 13, No. 1, p 183-188, February 1977. 6 fig, 1 tab,
20 ref.
37
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Descriptors: *Soil water movement, *Mathematical models, *Adsorption, *Solutes,
Equations, Analytical techniques, Theoretical analysis, Soils, Seepage, Transfer.
A given chemical may react at different rates with various soil constituents, and
the chemical may be involved in several kinds of reactions. A combination of
equilibrium and kinetic adsorption models was hypothesized to describe the nature
of the overall reaction. An analytical solution to the one-dimensional convective-
dispersive transport equation with a combination linear Freundlich isotherm and
first-order reversible kinetic adsorption model was developed. The individual^and
combined effects of the model parameters on the breakthrough curves and retention
profiles were examined. The combination equilibrium-kinetic model was shown to be
applicable to pesticide, nutrient, and metal transport in soils,
77:02G-022
TRANSPORT OF REACTIVE SOLUTES THROUGH MULTILAYERED SOILS,
Selim, H.M., Davidson, J.M., and Rao, P.S.C.
Florida University, Department of Soil Science, Gainesville, Florida.
Soil Science Society of America Journal, Vol. 41, No. 1, p 3-10, January-February,
1977. 15 fig, 2 tab, 18 ref.
Descriptors: *Soil water movement, *Solutes, *Adsorption, Soil water, Saturated
flow, Unsaturated flow, Soils, Sands, Loam, Laboratory tests, Mathematical models,
Dispersion, Effluents, Sorption, Agriculture, Soil science, Path of pollutants.
Solute transport through saturated and unsaturated multilayered soils was studied
using laboratory experiments and finite difference approximations of the solute
transport equation. Soil water and physical characteristics as well as solute
sorption properties were measured and/or calculated for each soil layer. Linear
and nonlinear equilibrium and kinetic adsorption processes were used to predict
adsorption in each layer. Water flux was assumed constant for water-saturated
and unsaturated layered soil profiles. For all adsorption processes considered,
the calculated results showed that the order in which the soil layers were strati-
fied in a water-saturated profile did not influence the effluent solute concen-
tration distribution. For unsaturated layered soil profiles, the results showed
that effluent solute distributions can be predicted with an average water content
within individual soil layers. Experimental results from the miscible displace-
ment of 36C1 and 14C-labeled 2,4-D ((2,4-dichlorophenoxy) acetic acid), through a
two-layered soil column supported the calculated results.
77:026-023
WATER MOVEMENT THROUGH PEDAL SOILS: I. SATURATED FLOW,
Anderson, J.L., and Bouma, J.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Soil Science Society of America Journal, Vol. 41, No. 2, p 413-418, March-April,
1977. 4 fig, 4 tab, 24 ref.
Descriptors: *Soil water movement, *Saturated flow, *Clay loam, Hydraulic con-
ductivity, Dispersion, Soils, Laboratory tests, Tracers, Chlorides, Soil structure,
Groundwater, Groundwater movement, Hydrodynamics, Soil science.
Apparent dispersion coefficients were determined with a chloride tracer in 55-cm
long undisturbed columns from four pedal soil horizons of three pedons. Five
medium subangular blocky structures were compared with five coarse prismatic
structures, all with a silty clay loam texture. Dispersion coefficients (D), which
could not always be calculated due to "nonideal" behavior to the flow system, were
significantly different for the two types of structures. Application of an un-
limited quantity of traced water to drained columns resulted in very high disper-
sion, particularly for the subangular blocky structures. Some practical implica-
tions of the occurrence of hydrodynamic dispersion were discussed.
77:02G-024
WATER MOVEMENT THROUGH PEDAL SOILS II. UNSATURATED FLOW,
Anderson, J.L., and Bouma, J.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Soil Science Society of America Journal, Vol. 14, No. 2, p 419-423, March-April,
1977. 6 fig, 4 tab, 7 ref.
38
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Descriptors: *Soil water movement, *Unsaturated flow, *Clay loam, Hydraulic
conductivity. Dispersion, Soils, Laboratory tests, Tracers, Chlorides, Soil
structure, Groundwater, Groundwater movement, Hydrodynamics, Soil science.
Very high hydrodynamic dispersion, occurring during application of an unlimited
dose of chloride-traced water to 10 drained 55-cm long columns with undis-
turbed pedal soils, was strongly reduced by a daily application of 1 cm of water.
Dispersion in five columns with subangular blocky structures remained signifi-
cantly higher than that measured in five columns with prismatic structures.
Differences were explained by a hypothetical analysis of flow patterns in both
types of structure. Application of a surface crust strongly reduced dispersion
in the subangular blocky structures, even though the flow rate remained approxi-
mately 1 cm/day. This was attributed to lack of flow into the larger vertical
pores extending through the columns. Pronounced differences in terms of hydro-
dynamic dispersion were found between two types of structures from three soil
series, all with a silty clay loam texture, thereby demonstrating the potential
usefulness of routine soil structure descriptions as a correlative tool for
predicting certain aspects of physical behavior.
77:02G-025
CONTRIBUTION OF LATERAL SOIL WATER MOVEMENT ABOVE A PRAGIPAN TO STREAMFLOW,
Palkovics, W.E., and Petersen, G.W.
Delaware Valley College of Science and Agriculture, Department of Agronomy,
Doylestown, Pennsylvania.
Soil Science Society of America Journal, Vol. 41, No. 2, p 394-400, March-April,
1977. 7 fig, 2 tab, 31 ref.
Descriptors: *Soil water movement, *Streamflow, *Perched water, Groundwater,
Groundwater movement. Subsurface waters, Base flow. Streams, Wells, Observation
wells, Drainage, Hydraulic conductivity. Water balance, Water table, Hydrology.
A water balance approach to the hydrologic budget on a small mountainous water-
shed in central Pennsylvania was used to determine if lateral water flow perched
above a soil fragipan could be quantitatively related to streamflow. Perched
water table fluctuations were measured using a grid of 60 observation wells,
and streamflow was recorded using a weir. The site was monitored in mid-Novem-
ber when evapotranspiration was at a minimum and when no precipitation was re-
corded. Soil water yield due to perched water table decline was calculated,
hydraulic conductivity and the rate of water movement through the soil computed,
and the zone of water contribution to streamflow determined. Results indicated
that water yield from the soil aquifer explained streamflow. Saturated water
flow was shown to be the main mechanism of water movement, although unsaturated
flow may have been significant for short distances under low tensions. The
major zone of soil water contribution to streamflow was the more poorly drained
soils adjacent to the stream. Unsaturated soils on the upper mountain flanks
had little effect upon streamflow because of low gradient and large distance
from the stream.
77:02G-026
LATERALLY CONFINED, STEADY FLOWS OF WATER FROM SOURCES AND TO SINKS IN UNSATURATED
SOILS,
Raats, P.A.C.
Agricultural Research Service, Salinity Laboratory, Riverside, California.
Soil Science Society of America Journal, Vol. 41, No. 2, p 294-304, March-April,
1977. 8 fig, 36 ref.
Descriptors: *Soil water movement, Irrigation, *Model studies, Mathematical
models, Soils, Unsaturated flow, Subsurface irrigation, Equations, Agriculture.
The application of water along lines and at points is of interest in connection
with furrow, subsurface, and drip irrigation. The removal of water along lines
and at points is of interest in connection with uptake of water by plant roots
and a variety of devices used to extract water and measure fluxes in the laboratory
and in the field. Laterally confined, steady flows from line and point sources
at arbitrary distances below the soil surface and to line and point sinks at
arbitrary distances above an impermeable base were analyzed on the basis of the
39
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assumption that the hydraulic conductivity is an exponential function of the
pressure head. The results included expressions describing the flow pattern, the
distribution of the components of the flux, and the distributions of matrix flux
potential, pressure head, water content, and total head. The horizontal varia-
tions were described by trigonometric functions in problems involving llne
sources and sinks and by Bessel functions in problems involving point s°urces
and sinks. The regions below and above the sources and sinks were treated se
parately, subject, of course, to matching along the interface between the two
regions. The vertical variations were described by exponential dampings and by
surface and base reflections. For the flows to sinks, with each flow pattern
there is associated an infinite variety of distributions of the matric flux po-
tential, etc., corresponding to different suctions applied at the sinks, some
problems involving partial supply by sources and interception by sinks also were
treated,
77 :02G-027
A COMPARISON OF NUMERICAL SIMULATION MODELS FOR ONE-DIMENSIONAL INFILTRATION,
Haverkamp, R., Vauclin, M., Touma, J., Wierenga, P.J,, and Vachaud, G,
Universite Scientifique et Medicale, Institut de Mecanique, Grenoble (France),.
Soil Science Society of America Journal, Vol. 41, No. 2, p 285-294, March-April,,
1977. 6 fig, 4 tab, 34 ref, 1 append.
Descriptors: *Model studies, *Mathematical models, *Infiltration, Numerical
analysis, Soil water movement, Soils, Sands, Clays, Profiles, Moisture content,
Hydraulic conductivity, Computer models, Equations, Soil science, Simulation
analysis.
Six models, employing different ways of discretization of the nonlinear infil-
tration equation, were compared in terms of execution time, accuracy, and pro-
gramming considerations. All models yielded excellent agreement with water con-
tent profiles measured at various times in a sand column. The two explicit
models, the theta-based CSMP model and the h-based explicit model, used between
5 and 10 times more computer time than the implicit models. Results obtained
with the two models which used the Kirchhoff integral transformation were no
better than results obtained with the two h-based implicit models. The implicit
schemes with implicit or explicit evaluation of the hydraulic conductivity and
water capacity functions appear to have the widest range of applicability for
predicting water movement in soil with both saturated and nonsaturated regions.
Excellent agreement was obtained among water content distributions, infiltra-
tion rates, and cumulative infiltration volumes calculated with the implicit
finite difference model and with Philip's quasi-analytical solution.
77:02G-028
INFILTRATION EQUATIONS FOR SIMPLE SOIL SYSTEMS,
Collis-George, N.
Sydney University, Department of Soil Science, (Australia),
Water Resources Research, Vol. 13, No. 2, p 395-403, April 1977. 3 fig, 1 tab,
24 ref.
Descriptors: *Infiltration, *Soil properties, *Model studies, *Soil water move-
ment, *Infiltration rates, Mathematical models, Equations, Soils, Soil water,
Hortons law, Dispersion.
Empirical equations and physically based equations used to describe vertical in-
filtration into simple soil systems were compared with experimental data. An
empirical equation was proposed which satisfies the conditions that cumulative
infiltration is proportional to the square root of time at short times and reaches
a steady-state infiltration rate at long times. The equation, i = i sub o (square
root of tanh T) + Kt, describes the observed behavior of simple soil systems at all
times; where i is the cumulative infiltration at time t, K is the infiltration
rate at steady-state, i sub o = S(square root of t sub c), and T = t/t sub c,
The sorptivity, S, and a time parameter, t sub c, are soil properties determinable
experimentally- The Green and Ampt equation and the Horton equation do not sat-
isfy observed behavior at all times, the former failing at long times and the
latter at short times. The equation of van der Want, the linearized Fokker-
Planck equation of Philip, and the nonlinearized Fokker-Planck equation of Knight
and Philip do not describe the observed behavior of simple soil systems over the
whole time range as precisely as the proposed empirical equation. Since i sub o
-------
is not an independent part of the equations, its numerical value is defined by
the independent parameters S and K; and for the materials examined, the numeri-
cal value is generally not the same as the experimental value. Procedures were
outlined for treating experimental data, not necessarily complete for all times,
to produce the three parameters, K, S, and t sub c for simple systems, and for
description infiltration into cracking clays or in cases where ultrashort time
effects occur.
77:02G-029
VERTICAL INFILTRATION IN DRY SOIL,
Brutsaert, W.
Cornell University, School of Civil and Environmental Engineering, Ithaca, New
York.
Water Resources Research, Vol. 13, No. 2, p 363-368, April 1977. 26 ref.
Descriptors: *Infiltration, *Soils, *Vertical migration, *Infiltration rates,
Dry beds, Sorption, Soil water movement, Capillary conductivity, Equations,
Mathematical studies.
An approximate method was proposed to integrate the ordinary differential equations
governing the terms in Philip's series formulation of the water content profile.
The method is related to the weighing solution used earlier for the sorption pro-
blem, and it is intermediate between the quasi-steady state method and the sharp
front method. In a comparison with an available exact solution, it was shown
that the derived solution is usually accurate to within less 1%. The water con-
tent profile and the infiltration rate can be expressed concisely in terms of
soil physical parameters by making use of suitable expressions for the soil water
diffusivity and for the capillary conductivity. As an illustration, the infil-
tration rate was calculated for the Averjanov-Irmay capillary conductivity and
for the author's three-parameter power function diffusivity. Inspection of two
extreme cases in the calculation finally lead to a new infiltration equation in
closed form which is valid for short and for large times of infiltration.
77:02G-030
FLOW CHARACTERISTICS DURING INFILTRATION INTO A HORIZONTAL SAND COLUMN,
Poulovassilis, A.
Agricultural Research Council, Unit of Soil Physics, Cambridge (England).
Water Resources Research, Vol. 13, No. 2, p 369-374, April 1977. 9 fig, 13 ref.
Descriptors: *Infiltration, *Diffusivity, *Soil water movement. Soil water, Flow,
Laboratory tests, Darcys law. Hydraulic conductivity, Permeability, Groundwater,
Groundwater movement, Hysteresis, Soil moisture, Reynolds number, Tensiometers,
Porous media, Soils.
Experimental water content profiles established during infiltration into a hori-
zontal sand column were compared with theoretical profiles calculated from the
soilwater diffusivity, which was determined independently of the infiltration
process. Discrepancies between the theoretical and experimental profiles were
found. In particular, the experimental profiles for small times showed a re-
tardation of the penetration which became more pronounced as the water content
increased, and no unique relationship between the water content and the variable
lambda=x/square root of t (x being the distance and t the time) was found. Thus,
the experimental profiles gave incorrect and varying soil water diffusivities.
The comparison of the actual flow rate q with the rate q1 given by the product
of the hydraulic conductivity and the observed potential gradient showed that
q = alpha q1, where alpha is between 0 and 1, alpha varying with the water con-
tent and the potential gradient. The effect of the "less than proportional"
flow on the profile development was discussed. It was argued that the infiltra-
tion process at relatively late times was conditioned by the profile development
during the very early stages. Previous experimental infiltration work was dis-
cussed, and it was argued that two mechanisms able to produce nonDarcian be-_
havior may be responsible for the various reported infiltration patterns. Finally,
the results of the present work were discussed in terms of a critical Reynolds
number where the flow becomes nonDarcian.
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77:02G-031
SCALING FIELD-MEASURED SOIL HYDRAULIC PROPERTIES USING A SIMILAR MEDIA CONCEPT,
Warrick, A.W., Mullen, G.J., and Nielsen, D.R.
Arizona University, Department of Soils, Water and Engineering, Tucson, Arizona.
Water Resources Research, Vol. 13, No. 2, p 355-362, April 1977. 2 fig, 1 tab,
12 ref.
Descriptors: *Hydraulic properties, *Soils, *Scaling, *Hydraulic conductivity,_
*Soil physical properties, Soil water movement, Unsaturated flow, Hydrology, Soil
physics, Flow, On-site investigations.
Field data for soil water characteristic relationships and unsaturated hydraulic
conductivity were scaled by using the concept of similar media in order to study
water flow in spatially varying soils. Data observed by different investigators
at three geographic areas were used. The soil water characteristic data con-
sisted of 840, 900, and 512 observations, while data for the unsaturated hydraulic
conductivity (available from only one of the three sources) consisted of 2,640
observations. In the process of scaling the data, a best fit for the scaled data
was defined in terms of a sum of squares about an "average" curve, using one value
for the scaling parameter for each sampling location. Comparisons made between
curves fitting the data and curves fitting the scaled data showed that scaling
reduces the sums of squares by amounts varying from 34 to over 90%. For similar
media, the scaling parameter determined at a given sampling location for the soil
water characteristic relationship (a sub r from h(S)) should be identical to the
scaling parameter for the unsaturated hydraulic conductivity (a sub r from K(S)).
Although the parameters were highly correlated (r = 0.91) for the only set of data
available, a sub r from h(S) values were shown to be more effective in scaling the
unsaturated hydraulic conductivity data than were a sub r from K(S) values in
scaling soil water characteristic data.
77:02G-032
EFFECTS OF SPATIAL VARIABILITY OF SOIL HYDRAULIC PROPERTIES IN WATER BUDGET
MODELING,
Peck, A.J., Luxmoore, R.J., and Stolzy, J.L.
Commonwealth Scientific and Industrial Research Organization, Division of Land
Resources Management, Wembley (Australia).
Water Resources Research, Vol. 13, No. 2, p 348-354, April 1977. 4 fig, 4 tab,
22 ref.
Descriptors: *Soil properties, *Hydraulic properties, *Hydrologic budget, *Model
studies, *Tennessee, Soil horizons, Hydraulic conductivity, Precipitation (atmo-
spheric), Rain-runoff relationships, Soil water, Soil profiles, Darcys law, Re-
tention, Infiltration, Evapotranspiration.
There is appreciable spatial variability of soil properties on the scale of a water-
shed of a field even in a single soil type. The spatial variation of soil water
characteristics in an area was simulated from average properties and the assump-
tion of scale heterogeneity. Simulated soil water characteristics and other data
representing forest vegetation were used in a model to simulate water budgets over
part of a watershed in eastern Tennessee for average April and July weather. Pre-
cipitation was assumed to be uniform over the area, and there was no runoff even
from the least permeable soil during the months simulated. The spatial variability
of soil water conditions had only a small effect on evapotranspiration. Water
storage in the soil profile changed, so that the drainage flux beyond the root zone
tended to become uniform throughout the area simulated. The characteristic micro-
scopic length of the soil was assumed to be normally distributed in an area, and
equations were developed for calculating average soil water characteristics from
the retention curves and hydraulic conductivities of a number of soil samples.
Components of the water budgets simulated with average soil water characteristics
were in excellent agreement with the simulated behavior of the spatially variable
soil unit as a whole. The result does not imply similar agreement for other dis-
tribution functions and soil-plant-weather combinations, but the methodology dev-
eloped may be applied to investigate similar problems.
77:02G-033
HYSTERETIC STEADY STATE SOIL WATER PROFILES,
Poulovassilis, A., and El-Ghamry, W.M.
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Agricultural Research Council, Unit of Soil Physics, Cambridge (England)
Water Resources Research, Vol. 13, No. 3, p 549-557, June 1977. 11 fig, 9 ref.
Descriptors: *Soil water, *Hysteresis, *Soil water movement, *Model studies,
Soil moisture. Profiles, Theoretical analysis, Mathematical models, Laboratory
tests, Analysis, Hydraulic conductivity, Unsaturated flow, Hydraulic models,
Porous media, Capillary water, Fringe water, Pressure head, Moisture content,
Data collections, Foreign research.
The shape of the hysteretic steady-state soil water profile was examined theoreti-
cally. It was shown that the hysteretic steady-state profile which results after
wetting acquires usually minimum values of the soil water pressure head, of the
hydraulic conductivity, and of the water content, values smaller than the asymptotic
values approached at large heights. In contrast, the hysteretic steady-state pro-
files which result after drying do not show such minimum values. Experimental
hysteretic steady-state profiles established in a vertical sand column confirmed
the theoretical predictions and were in agreement with the predictions calculated
numerically from the flow equation. It was concluded that the effects hysteresis
on the soil water profile development may influence seriously the retention and
movement of water in and out of the soil zone between the soil surface and the
water table and, therefore, may modify the environment of plant root growth.
77:020-034
SATELLITE MICROWAVE OBSERVATIONS OF SOIL MOISTURE VARIATIONS,
Schmugge, T.J., Meneely, J.M., Rango, A, and Neff, R.
National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt,
Maryland.
Water Resources Bulletin, Vol. 13, No. 2 p 265-281, April 1977. 11 fig, 1 tab,
7 ref.
Descriptors: *Remote sensing, *Soil moisture, *Central United States, Soils,
Vegetation, Vegetation effects, Satellites (artificial), Aircraft, Microwaves,
Rainfall, Antecedent precipitation, Precipitation (atmospheric), Soil water,
Crops, Soil moisture meters, Measurement, Monitoring, Water resources, Agriculture.
Results from studies in the Illinois-Indiana and Texas-Oklahoma areas indicated
that satellite microwave observations at the 1.55 cm wavelength are responsive to
relative moisture variations in the near surface layer of the soil. Because
significant vegetation cover absorbs the 1.55 cm microwave emission from the soil,
the target area must be predominantly bare soil or low density vegetation cover
for meaningful measurements to result. The 25 km resolution of the satellite sen-
sor limits application of the microwave techniques to large areas such as water-
sheds or agricultural districts rather than individual fields. In general, at
1.55 cm, there is an inverse relationship between microwave brightness temperature
and changes in soil moisture levels (as indicated by antecedent rainfall) in
agricultural regions before planting of crops or during the early growing season
when vegetation cover is sparse. Even early season observations should be of great
value in deciding on the time and type of crop planting and for initial irrigation
scheduling when the root zone is still in close proximity to the surface.
77:02G-035
NUMERICAL ANALYSIS OF TWO-DIMENSIONAL INFILTRATION AND REDISTRIBUTION,
Perrens, S.J., and Watson, K.K.
University of New England, School of Natural Resources, Armidale (Australia).
Water Resources Research, Vol. 13, No. 4, p 781-790, August 1977, 6 fig, 36 ref.
Descriptors: *Infiltration, *Soil water, *Soil moisture, *Model studies, Mathe-
matical models, Soils, Soil types. Hysteresis, Hydraulic conductivity, Soil water
movement, Pressure, Pressure head, Wetting, Soil physics, Soil science.
The two-dimensional flow equation for the movement of water in unsaturated porous
materials was used to study an infiltration-redistribution sequence in which the
surface flux is spatially nonuniform. A numerical analysis is based on^a finite
difference scheme involving the use of iterative alternating direction implicit
techniques was found to describe the two-dimensional flow process satisfactorily.
The program incorporates an interpolation-type hysteresis model which enables
temporal as well as spatial variations of flux to be simulated. The flow regime
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was discussed with reference to two porous materials which have contrasting hydro-
logic characteristics. The two-dimensional profile distributions of water content
and pressure head were represented at significant times by a series of perspective
diagrams.
77:02G-036
NITRATE MOVEMENT IN CLAY SOILS AND METHODS OF POLLUTION CONTROL,
Swoboda, A.R.
Texas ASM University, Department of Soil and Crop Sciences, Texas Agricultural
Experiment Station, College Station, Texas.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 19-25, May 16-19, 1977. 2 fig,
5 tab, 6 ref.
Descriptors: Nitrates, Clays, Soils, Soil investigation, Pollution, Pollution con-
trol, Leaching, Lysimeters, Fertilizers, Runoff, Model studies, Nitrification, Crop
response.
Movement of nitrates was measured in soils to determine quantitative amounts of
losses. Leaching losses in lysimeters ranged from 0.04 to 6 percent depending on
nitrogen source and climatic conditions. Nitrate concentrations in shallow wells
within watersheds indicated that nitrates from applied fertilizer was leaching into
the shallow groundwaters. Concentrations as high as 60 ppm NO3-N were found in
some wells after the initial rains following fertilization. Runoff from the water-
shed contained very little nitrate and amounted to less than 4 percent of the ferti-
lizer applied. A descriptive model of nitrate movement in clay soils is presented.
Methods of reducing nitrate leaching in soils are discussed. Field studies indi-
cated that inhibiting nitrification was an effective means of reducing nitrate
movement from ammonium fertilizers. Slow release sulfur coated urea also reduced
nitrate movement when applied in the fall or winter. Delaying fertilization until
planting was also an effective means of reducing nitrate losses without reducing
yields.
77:02G-037
EFFECT OF THREE IRRIGATION SYSTEMS ON DISTRIBUTION OF FERTILIZER NITRATE NITROGEN
IN SOIL,
Onken, A.B., Wendt, C.W., Wilke, O.C., Hargrove, R.S., and Bausch, W.
The Texas A & M University System, Texas Agricultural Experiment Station, Lubbock,
Texas.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 27-32, May 16-19, 1977. 9
tab, 2 ref.
Descriptors: Irrigation, Irrigation systems, Fertilizers, Nitrates, Soils, Ferti-
lization, Corn, Sprinkler irrigation, Furrow irrigation, Subsurface irrigation.
Sweet corn was grown two years on a Miles loamy fine sand fertilized with band
applied 15N enriched sodium nitrate. Two plots, 6 x 6 m, were established under
each of the three irrigation systems-sprinkler, furrow and subirrigation. A
starter band of fertilizer was applied 7.6 x 7.6 cm from the seed with the rest
sidedressed 25 cm either side of the center of the seedbed. Total nitrogen applied
was 124 kg/ha in 1973 and 105 kg/ha in 1974. In 1974, each of the six plots that
were established in 1973 were divided in half, one half receiving 15N enriched
fertilizer as sodium nitrate, and the other half receiving the same amount of unen-
riched sodium nitrate. Soil samples were taken periodically from furrow to furrow
in lateral distance increments of 25 cm and through the starter fertilizer band
to a depth of 5.2 m in 30 cm increments. Plant samples were obtained at the end
of each growing season. Soil and plant samples were analyzed using standard pro-
cedures. Fertilizer nitrogen moved differently under the three irrigation systems.
When sprinkler-irrigated, fertilizer bands tended to maintain their integrity
during downward movement. Under furrow irrigation, fertilizer bands tended to
merge in the center of the bed and move downward. Under subirrigation, fertilizer
tended to move down under the furrows. At the end of two crop years, greatest
depth movement of fertilizer nitrogen was under sprinkler irrigation and least
under subirrigation.
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77:020-038
VARIABILITY OF NITRATE LEACHING WITHIN DEFINED MANAGEMENT UNITS,
Lund, L.J., and Pratt, P.F.
California University, Riverside, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 45-53, May 16-19. 1977.
6 fig, 6 tab, 20 ref, 7 equ.
Descriptors: Soils, Soil investigations, Fertilizers, Fertilization, Return flow,
Nitrates, Leaching, Sampling, California.
In attemping to relate nitrate concentrations below root zones to root zone soil
characteristics, the experimental approach has consisted of a comparison of a
number of sites within a defined management unit or field. The basic assumption
in this approach has been that the management of the field is uniform and varia-
tions in nitrate leaching result from variations in soil characteristics. How-
ever, results reported herein show that even within a field of limited size, other
sources and sinks can be significantly different at various sampling locations.
The variation in these factors for a number of fields in the Santa Maria Valley,
California is discussed.
77:02G-039
FIELD MEASURED FLUX OF VOLATILE DENITRIFICATION PRODUCTS AS INFLUENCED BY SOIL
WATER CONTENT AND ORGANIC CARBON SOURCE,
Rolston, D.E., Goldhamer, D.A., Hoffman, D.L., and Toy, D.W.
California University, Department of Land, Air, and Water Resources, Soils and
Plant Nutrition Section, Davis, California,
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 55-61, May 16-19, 1977.
5 fig, 1 tab, 10 ref, 2 equ.
Descriptors: Irrigation, Soils, Soil investigations, Soil moisture, Return flow.
The amount of NO3 in irrigation return flow waters is dependent upon each of the
components of the N cycle in soils. One of those components for which absolute
amounts and rates are not well known is denitrification. Volatile denitrification
products, primarily N2O and N2, are evolved whenever anoxic sites develop within
the soil and when sufficient carbon is available. Absolute amounts and rates of
denitrification from a Yolo loam field profile at Davis, California, were studied
in relation to the influence of soil-water content and organic carbon source.
Field plots were intensely instrumented with soil atmosphere samplers, soil solu-
tion samplers, and tenslometers. Soil-water pressure heads (h) in the upper 15
cm of soil were maintained constant at -15 and -70 cm of water. Three levels of
soil carbon were evaluated from plots cropped with ryegrass, uncropped plots, and
plots to which manure was mixed in the top 10 cm of soil. Fertilizer was applied
at the rate of 300 kg N ha-1 as KN03 enriched with 20 and 40 percent 15N for the
h = -15 and h = -70 cm treatments, respectively. The flux of volatile gases at
the soil surface was measured from the accumulation of N20 and 15N2 beneath an
airtight cover placed over the soil surface for 1 or 2 hours per day. Denitrifi-
cation occurred in order of decreasing magnitude in manure (h = -15 cm), manure
(h = -70 cm), uncropped (h = -15 cm), and uncropped (h = -70 cm) plots. Approxi-
mately 70 percent of the fertilizer nitrogen was denitrified for the manure (h =
-15 cm) treatment. Approximately 1 percent of the added fertilizer was denitrified
in the uncropped (h = -70 cm) treatment.
77:020-040
SOIL NITRATE CONCENTRATIONS IN CORN PLOTS TREATED WITH ISOTOPICALLY LABELED
NITROGEN FERTILIZER,
Broadbent, F.E., and Carlton, A.B.
California University, Department of Land, Air and Water Resources, Soils and
Plant Nutrition Section, Davis, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 63-69, May 16-19, 1977.
8 fig, 4 tab, 6 ref.
Descriptors: Nitrates, Nitrogen, Soils, Fertilizers, Sampling, Soil physical
properties.
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Soil solution composition has been monitored for 3 years at depths ranging from
30 to 300 cm at an experimental site on Yolo fine sandy loam where 15N-depleted
ammonium sulfate has been applied at 0, 90, 180, and 360 kg N per year. Samples
have been taken at approximately 2-week intervalsduring the growing season and
less frequently during the winter and early spring. In unfertilized plots re-
ceiving 60 cm/yr irrigation water N03-N concentrations fluctuated widely near the
surface, ranging from 3-4 up to about 35 ppm over a 2-1/2 year period. At lower
depths fluctuations were not as great, but at 300 cm N03-N consistently remained
above 10 ppm. At 90 and 180 kg-fertilizer N, the latter level being sufficient
to produce the maximum grain yield, very little N03-N derived from fertilizer was
found below 120 cm. However, at the 360 kg level, fertilizer-derived nitrate was
found to constitute a significant fraction of the total at all depths down to
300 cm.
77:02G-041
THEORETICAL AND EXPERIMENTAL OBSERVATIONS OF WATER AND NITRATE MOVEMENT BELOW A
CROP ROOT ZONE,
Biggar, J.W., Tanji, K.K., Simmons, C.S., Gupta, S.K., and Maclntyre, J.L.
California University, Department of Land, Air and Water Resources, Davis,
California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 71-77, May 16-19, 1977.
9 fig, 1 tab, 4 ref, 3 equ.
Descriptors: Soils, Soil investigations, Soil water movement, Soil water, Crop
production, Leaching, Nitrogen, Irrigation.
A report of the progress of an experiment which attempts to deal with the spatial
variability of a field soil is presented. The experimental objective is to mea-
sure the flux of water and nitrate leaching below the root zone of a crop by ex-
amining the behavior of nitrogen applied to a corn crop grown under irrigation.
77:02G-042
MINIMIZING SALT IN RETURN FLOW BY IMPROVING IRRIGATION EFFICIENCY,
van Schilfgaarde, J.
United States Department of Agriculture, Agricultural Research Service, United
States Salinity Laboratory, Riverside, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 81-98, May 16-19, 1977.
19 fig, 4 tab, 24 ref.
Descriptors: Salinity, Saline water, Irrigation efficiency, Agriculture, Colorado
river, Leaching, Arizona.
Return flow from irrigated agriculture has been identified as the major source of
salinity in the Colorado River that may be controlled. Thus, if the trend of
increasing salinity is to be reversed, it appears that irrigated agriculture must
bear a large portion of the burden. Research at the United States Salinity Labora-
tory indicates irrigated agriculture can reduce its contribution by efficient ir-
rigation that provides water of low salinity in the upper portion of the crop root
zone while the salinity of the water in the lower portion can be permitted to con-
centrate considerably more than had previously been suspected without decreased
yields. If these results hold true under field conditions, the leaching require-
ment of most crops grown with Colorado River water could be reduced below 10%.
Lower leaching requirements, if achieved, would also reduce salt discharge to the
river due to precipitation of lime and gypsum in the soil and because of decreased
salt pickup from saline underground sources. To evaluate the minimum leaching
concept for alleviating the salinity problem of a major river basin, two field
studies have been initiated in the Wellton-Mohawk Irrigation and Drainage District
of southwestern Arizona. The first field experiment was installed in December 1973
in citrus on coarse-textured, mesa soil, and the second was started in September
1974 in alfalfa on fine-textured, valley soil. The paper will describe the experi-
mental design of both experiments and initial data on crop water use, soil salinity
profiles, and leaching fractions achieved will be presented.
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77:02G-043
AREAL PREDICTIONS OF SOIL WATER FLUX IN THE UNSATURATED ZONE,
Warrick, A.W.
Arizona University, College of Agriculture, Department of Soils, Water and
Engineering, Tuscon, Arizona.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 225-231, May 16-19 1977
8 fig, 14 ref.
Descriptors: Soil water, Soil water movement. Soils, Soil investigations. Irri-
gation, Salinity, Hydraulic conductivity.
Irrigation, salinity and potential ground or surface water pollutants are inti-
mately related to water and solute movement in the soil profile. Ideally, soil
water fluxes and water composition are managed in order to provide a desirable
plant growing environment and/or acceptable quantities and qualities of drainage
water. The problem of predicting or averaging such fluxes is very difficult due
to the intrinsic variability of the soil's physical and chemical properties. In
this study, predictions of soil water flux are made accounting for the spatial
variability of the soil water parameters. Calculations are made using field-
measured distributions of conductivity and soil water tension water content
relationships for Panoche loam and Pima clay loam soils. In the second set of
calculations, flux distributions are found using the more cumbersome, finite dif-
ference solution to the nonlinear moisture flow equation. This allows inclusion
of more realistic boundary conditions as well as plant water uptake. The results
are a step towards finding the most effective way of determining and expressing
water flux as a function of time. Also, addressed are reliability of areal pre-
dictions and measurements.
77:02G-044
HYDRO-SALINITY MODELS: SENSITIVITY TO INPUT VARIABLES,
Oster, J.D., and Wood, J.D.
United States Department of Agriculture, Agricultural Research Service, United
States Salinity Laboratory, Riverside, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 253-259, May 16-19, 1977.
7 fig, 2 tab, 6 ref, 9 equ.
Descriptors: Model studies, Simulation analysis, Water quality, Return flow,
Salinity, Irrigation efficiency.
Return flows estimated from salinity, or a water budget analysis, exhibit opposite
sensitivities to increasing field irrigation efficiencies. However, the sensiti-
vities of both methods to assess return flows may be complementary if both are used
to obtain an optimized estimate of return flows. The degree of data uncertainty
would undoubtedly be greater in areas with multiple return flow paths, greater
sources of underflows and rainfall, and shorter growing seasons.
77:026-045
AGRICULTURAL DRAINAGE PROBLEMS OF THE SAN JOAQUIN VALLEY,
Price, E.P-
United States Bureau of Reclamation, Sacramento, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 283-287, May 16-19, 1977.
2 fig, 1 tab.
Descriptors: Agriculture, California, Drainage districts, Drainage practices.
Drainage.
A brief description of the physical setting of the San Joaquin Valley and the drain-
age problems anticipated are presented. Estimates are preliminary and subject to
revision as studies continue.
77:02G-046
PORTLAND CEMENT AS A SOIL AMENDMENT FOR CORN AND SOYBEANS,
Stivers, R.K., Swartzendruber, D., and Nyquist, W.E.,
Purdue University, Department of Agronomy, West Lafayette, Indiana 4/SO/.
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Agronomy Journal, Vol. 69, No. 6, p 961-964, November-December, 1977. 3 tab,
1 ref.
Descriptors: Corn, Soybeans, Soil amendment, Soil water, Hydraulic conductivity,
Infiltration, Soil properties, Soil physical properties, Soil treatment, Soil water
movement, Cements.
In the corn belt there are many areas of imperfectly drained soils, often adjacent
to well-drained soils in the same fields. Tile drainage of these imperfectly
drained soils helps remove excess water within the profile. Slow movement of water
into and through the Ap horizon of these soils is thought to contribute to reduced
crop yields in wet years. Since application of Portland cement (the binding ma-^
terial in concrete) to soil in a laboratory experiment increased water-stable soil
aggregate size as well as hydraulic conductivity of a soil, it was assumed that
cement would act similarly in the field and increase crop yields, particularly
under wet conditions.
77:02G-047
COMPARISON OF METHODS OF CALIBRATION OF A NEUTRON PROBE BY GRAVIMETRY OR NEUTRON-
CAPTURE MODEL,
Vachaud, G., Royer, J.M., and Cooper, J.D.
Grenoble-1 University, Inst. de Mecanique, (France).
Journal of Hydrology, Vol. 34, No, 3/4, p 343-356, August 1977. 3 fig, 1 tab,
21 ref.
Descriptors: *Soil moisture meters, *Soil water, *Calibrations, *Analytical
techniques, *Nuclear moisture meters, Instrumentation, Chemical properties,
Nuclear meters, Gravimetry, Soil analysis, Mathematical studies. Soil properties,
Soil moisture, Gravimetric analysis, Soil tests, Moisture content, Methodology.
Presented was a systematic analysis of 2 methods used for determining calibration
curves of neutron probes. The uncertainties resulting from the use of the gravi-
metric method, with a linear correlation between count rates and water content of
soil samples, were considered first. Particular care was given to the determina-
tion of errors in the values of water content and count rates and to the difficul-
ties arising from the choice of the correlation technique. The neutron-calibration
curve of the soil also was obtained with a technique based on the determination
of neutron thermal absorption and diffusion constants. The importance of errors
associated with the method was also analyzed. Different field examples>then were
presented. It appears that the neutron-capture technique should be particularly
well suited for determining the calibration curve of clay soils or heterogeneous
materials for which the gravimetric calibration technique cannot be applied with
confidence. On the other hand, it also was shown that for a soil with a very
well-defined gravimetric calibration curve, the neutron-capture technique gives
results still at least as good as with the former method.
77:02G-048
THE UNSTEADY GROUNDWATER MOUND BELOW AN IRRIGATION DITCH OR LEAKY CANAL,
Young, E.G.
Agricultural Research Council, Unit of Soil Physics, Cambridge (England).
Journal of Hydrology, Vol. 34, No. 3/4, p 307-314, August 1977. 3 fig, 6 ref.
Descriptors: *Soil water, *Seepage, *Canals, *Model studies, Laboratory tests,
Mathematical models, Irrigation, Groundwater, Soil water movement, Groundwater
movement, Water table, Equations, Irrigation ditches, Irrigation canals. Infil-
tration.
The groundwater mound which develops below an irrigation ditch or leaky canal was
investigated experimentally using a hydraulic sand-tank model and a Hele-Shaw
analogue. The results showed that the mound built up in height at a rate propor-
tional to the cube root of time and moved laterally at a rate proportional to the
cube root of the time squared, as predicted from a solution of the Boussinesq
equation, obtained numerically after using Barenblatt's transformation.
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77:020-049
MODELING SOIL WATER MOVEMENT FOR TRICKLE IRRIGATION-PHASE II,
Warrick, A.W., and Lomen, D.O.
Arizona University, Department of Soils, Water and Engineering, Tucson, Arizona.
Available from the National Technical Information Service, Springfield, Virginia
22161 as PB-272, 625, Price codes: A03 in paper copy, A01 in microfiche. Comple-
tion Report, August 1977. 27 p, 13 fig, 4 tab, 34 ref.
Descriptors: *Unsaturated flow, *Soil water movement, *Model studies, Irrigation,
Evaporation, Moisture content, Evapotranspiration, Fruit crops, Orchards.
This study is a continuation of the previous project whose goal was to develop
techniques for the solution of the moisture flow equation for conditions of
trickle and high-frequency irrigation. Several solutions have been found for
the linearized forms of the moisture equation including flow from a line source
above a shallow water table, flow from lines and points with evaporation at the
surface and one and two-dimensional flows with plant water uptake. Comparisons
of the analytical solutions for the linearizing assumptions were made with finite
difference results of the nonlinear moisture equation. Results are somewhat en-
couraging. Conditions favoring the analytical over the numerical solutions are
short irrigation cycles, uncertain input data, complex geometries, and expensive
computer time. In addition to the mathematical modeling, field measurements were
made regarding the microclimate surrounding lemon trees in a trickle-irrigated
orchard. Results in June showed evapotranspiration to be on the order of 0.2 -
0.4 of the open pan evaporation and about three times as large if just the canopy
area was considered.
77:02G-050
RAINFALL INFILTRATION INTO BARE SOILS,
Morin, J., and Benyamini, Y.
Ministry of Agriculture, Soil Conservation and Drainage Division, Tel-Aviv (Israel).
Water Resources Research, Vol. 13, No. 5, p 813-817, October 1977. 5 fig, 3 tab,
6 ref, 1 append.
Descriptors: *Infiltration, *Model studies, *0n-site investigations,. Mathematical
models, Soils, Soil properties, Precipitation (atmospheric), Rainfall, Rainfall
intensity, Mulching, Impact (rainfall), Infiltration rates, Agriculture.
Raindrop impact destroys the surface aggregates of soils and gradually forms a
continuous crust. Infiltration rates of bare soils are determined by the mentioned
process. A theoretical model presented previously was tested under field conditions
with a sandy loam soil. The effect of the crust's structure was tested under three
rainfall intensities and in wetting and drying cycles. The results of the tests
confirmed the theoretical model. The study demonstrated quantitatively that the
major factor determining the reduction of infiltration rates is crust formation
and not moisture regime.
77:026-051
SOIL THERMAL DIFFUSIVITY DETERMINATION FROM OVERSPECIFICATION OF BOUNDARY DATA,
Singh, S.R., and Sinha, B.K.
Punjab Agricultural University, Department of Agricultural Engineering, Ludhiana-
141004, India.
Soil Science Society of America Journal, Vol. 41, No. 5, p 831-834, September-
October, 1977. 1 fig, 1 tab, 18 ref.
Descriptors: Heat, Diffusivity, Soils, Soil investigations, Soil temperatures,
Soil profiles, Mathematical studies.
The heat conduction equation has been solved for evaluating thermal diffusivity of
soils by overspecifying the usual boundary conditions in terms of the thermal grad-
ient at the boundary surface. Solutions have been obtained for difference Dirichlet-
type boundary conditions describing the boundary temperature. These were (a) lin-
early rising/falling, (b) exponentially rising, (c) exponentially falling, and (d)
sinusoidal. The thermal gradient in the soil profile was evaluated using a cubic
spline. Field data were analyzed firstly by representing the surface temperature
as linearly rising and secondly as sinusoidal. More consistent results were ob-
tained with the help of the first approximation which represented the boundary
data closely. This shows that a close approximation of boundary condition by an^
appropriate function is essential to get reliable values of the thermal diffusivity-
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77:02G-052
ON THE USE OF THE LANGMUIR EQUATION IN THE INTERPRETATION OF "ADSORPTION"
PHENOMENA,
Veith, J.A., and Sposito, G.
Institute for Anorganische Chemie der Freien University, Berlin, 1 Berlin 33,
Fabeckstrasse 34/36, West Germany.
Soil Science Society of America Journal, Vol. 41, No. 4, p 697-702, July-August,
1977. 5 fig, 29 ref, 12 equ.
Descriptors: Model studies, Simulation analysis, Anions, Soils, Soil investigations,
Phosphorus, Adsorption.
A theoretical discussion in terms of molecular theory and the results of model
experiments are employed to demonstrate that the conventional analysis of "anion
fixation" data, through linear least squares regression of the points in a Lang-
muir plot, usually will not be sensitive enough to show the failure of the Lang-
muir equation reaction. The theoretical discussion points out that although the
Langmuir equation is not restricted to two-dimensional phenomena (in other words,
adsorption), it cannot apply if the reacting anions must be present at some thres-
hold concentration before fixation occurs. An analysis of model experiments on
the reactions of OH(-) with Al(-) or Fe-resin and of Cl(-) with Ag-resin shows
that secondary precipitation phenomena always result in a statistically signifi-
cant, linear correlation of the variables in a Langmuir plot if the concentration
of the reacting anions is much larger than the threshold value needed to initiate
precipitation of the secondary solid phase. This condition generally can be
expected to be met when anions such as 0-phosphate react with soils or soil con-
stituents .
77 :02G-053
SOIL ACIDITY FROM LONG-TERM USE OF NITROGEN FERTILIZER AND ITS RELATIONSHIP TO
RECOVERY OF THE NITROGEN,
Jolley, V.D., and Pierre, W.H.
Agricultural Home Economics Experiment Station, Ames, Iowa.
Soil Science Society of America Journal, Vol. 41, No. 2, p 368-373, March-April,
1977. 2 fig, 6 tab, 11 ref.
Descriptors: Nitrogen, Nutrients, Fertilizers, Fertilization, Corn, Crop re-
sponse, Nitrification, Crop production, Denitrification, Soils.
Two N-rate experiments in which corn had been grown continuously for 15 and 17
years were used: (1) to study quantitatively the amounts of acidity that had been
developed at different levels of N fertilization and (2) to determine to what
extent the acidity produced can be explained and predicted from the amounts of N
recovered in the crops and in the soil as N03-N and organic N. The measured
acidity was compared with the acidity calculated from N recovery, and both were
expressed as percentages of the theoretical (potential) acidity developed from
nitrification.
77:02G-054
TRACING VERTICAL TRANSLOCATION OF SOIL MOISTURE,
Ligon, J.T., Wilson, T.V., Allen, J.F., and Singh, U.P,
Clemson University, Department of Agricultural Engineering, South Carolina.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY10, Proceedings Paper 13290, p 1147-1158, October 1977. 8 fig, 8 ref, 1
append.
Descriptors: *Soil water movement, *Tritium, *South Carolina, Sampling,
Iodine, Iodine radioisotopes, Tracers, Radioisotopes, Diffusion, Soil water,
Groundwater, Seepage, Soil moisture, Soils, Clays, Unsaturated flow. Dispersion,
Drainage.
Tracer experiments using tritium tagged water were initiated during December 1972-
January 1973 to determine the rate of downward displacement of water in unsaturated
Piedmont profile. Tritium location was monitored by daily soil sampling immediately
after injection of activity and at frequencies decreasing to once every 6 months
after 1 year. At the end of 23 months, the maximum level of activity was 24.8 ft
(7.56 m) . The observed rate of movement will bring the maximum tritium activity
to the water table level of 65 ft (20 m) in about 6 years. Under conditions at
50
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the research site, lateral displacement of the materials was negligible. Some
detention of activity in the high-clay B-horizon of the soil was observed,
77:02G-055
IRRIGATION SCHEDULING WITH NEUTRON PROBE,
Gear, R.D., Dransfield, A.S., and Campbell, M,D
United States Department of the Interior, Bureau of Reclamation, Lower Colorado
Region, Boulder City, Nevada,
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR 3, p 291-298, September 1977. 3 fig, 3 ref.
Descriptors: Irrigation, Irrigation practices, Soil water. Soil moisture, Soil
water movement, Soil properties.
A simple accurate technique has been worked out to schedule irrigations, using a
graphic display of neutron probe measurements. The neutron probe design has
been changed to combine the sealer with the shield and provide a useful tool from
what has traditionally been used almost exclusively for research. The technique
used for scheduling irrigation requires only the identification of the refill
point for each field and the neutron measured water content with time.
77:02G-056
A QUICK METHOD FOR ESTIMATING SOIL WATER DIFFUSIVITY FUNCTIONS,
Miller, R.D,, and Bresler, E.
Cornell University, Agricultural Experiment Station, Department of Agronomy,
Ithaca, New York.
Soil Science Society of America Journal, Vol. 41, No. 5, p 1020-1022, September-
October, 1977. 1 fig, 4 ref.
Descriptors: *Diffusivity, *Soil water movement, *Infiltration, Model studies,
Mathematical models, Equations, Regression analysis, Analytical techniques, Soils,
Soil properties, Soil water, Physical properties, Laboratory tests, Soil science,
Wetting fronts, Horizontal infiltration.
Published data for horizontal infiltration into air dry nonsodic stable soil imply
excellent correlation between soil water diffusivity functions and the rate of ad-
vance of the visual wetting front in one dimensional horizontal infiltration ex-
periments. When suitably transformed, data for each of eight soils, ranging from
a clay loam to a sieved sand fraction, were represented remarkably well by a sin-
gle regression equation involving dimensionless variables. This suggests that the
same coefficients should apply to similar data for almost any soil. It was shown
that the data also can be expressed for a somewhat simpler regression equation,
involving only the simplest of experimentally measured quantities so that the
diffusivity function can be quickly estimated for any soil.
77:02G-057
QUANTITATIVE RELATIONSHIPS AMONG NUTRIENTS LEACHED FROM SOILS,
Terman, G.L.
Tennessee Valley Authority, National Fertilizer Development Center,- Soils and
Fertilizer Research Branch, Muscle Shoals, Alabama 35660.
Soil Science Society of America Journal, Vol. 41, No. 5, p 935-940, September-
October, 1977. 1 fig, 5 tab, 21 ref.
Descriptors: Nutrients, Fertilizers, Leaching, Soils, Soil investigations,
Anions, Cations, Lysimeters.
This study was undertaken in an attempt to quantify relationships among anions
(An) and cations (Cat) leached from soils. Several sets of published data on
leaching of ions from acid and nonacid soils were evaluated by linear regression
calculations based on the chemical equivalency of summation of Cat and summation
of An leached. Calcium, Mg, K, and Na comprised most of summation of Cat, and
N03, S04, and Cl, most of summation of An. Bicarbonate is also leached from
nonacid soils; H is assumed to account for most of the excess of summation of
An over summation of Cat in leachates from acid soils. Amounts of ions leached
were much more closely correlated with leachate volumes among soils and time
periods than with leachate volumes from various treatments for a given time period.
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77:02G-058
WATER INFILTRATION AND RUNOFF UNDER RAIN APPLICATIONS,
Hachum, A.Y., and Alfaro, J.F.
Utah State University, Department of Agriculture and Irrigation Engineering,
Logan, Utah.
Soil Science Society of America Journal, Vol. 41, No. 5, p 960-966, September-
October, 1977. 9 fig, 4 tab, 13 ref.
Descriptors: *Infiltration, *Runoff, *Model studies, *Lab.oratory tests, Simulated
rainfall, Mathematical models, Ponding, Pressure head, Wetting, Irrigation, Sprinkler
irrigation, Rainfall, Soils, Soil water, Saturation, Soil science.
Experiments to verify the validity and to evaluate the performance of rain infil-
tration models based on extending the Green and Ampt approach are lacking in the
literature. There are severe gaps between theory, validity, and practicality of
these models. In this study, a physically based model for describing infiltration
into a homogeneous deep stable soil profile with uniform initial water content
distribution was presented. The derivation of the model was based on the concept
of mapping the actual wetted soil zone into an equivalent rectangular saturated
zone with constant effective hydraulic conductivity and capillary pressure head
at the abrupt wetting front. The model took into account the initial water mobility
in the soil profile and predicted the system response under any rainfall pattern.
The proposed model was further simplified, for practical purposes, by grouping 3
basic input parameters into a single parameter, the Surface Saturation Index, The
validity of the model was tested and was supported strongly by the results of
laboratory experiments conducted on samples of 3 soils, 2 silt loams and a silty
clay loam, under 5 different (variable and constant) water application rate pat-
terns. It was found that the amount of runoff from a nearly symmetrical convex
variable rainfall pattern was very close to that which resulted from its equivalent
average constant application rate pattern, regardless of the significant differences
between the times at which runoff begins and the characteristics of infiltration
rates thereafter.
77:02G-059
MICRONUTRIENT CONCENTRATIONS IN SOIL SOLUTION AFTER AMMONIUM PHOSPHATE APPLICATIONS,
Mortvedt, J.J., and Osborn, G,
Tennessee Valley Authority, Soils and Fertilizer Research Branch, Division of Ag-
ricultural Development, Muscle Shoals, Alabama 35660.
Soil Science Society of America Journal, Vol. 41, No, 5, p 1004-1009, September-
October, 1977. 7 tab, 19 ref.
Descriptors: Ammonium, Fertilizers, Fertilization, Phosphates, Soils, Soil investi-
gations, Phosphorus.
Two fluid ammonium polyphosphates and an equimolar mixture on mono- and diammonium
phosphate, each with a solution pH of about 6.2, were well mixed with 1 kilogram
lots of several soils to supply 2,000 parts per million of P, which approximates
the P concentration in soil near a fertilizer band at a P rate of 50 kilograms
per hectare. Each soil was then moistened to 0.2 or 0.3 atm and stored in plastic
bags. After periods up to 28 days, soil samples were placed in a lucite cell and
a portion of the soil solution was expressed by N2 gas. These solutions were
analyzed for Cu, Fe, Mn, Zn, organic C, and total and orthophosphate P,
77:02G-060
TEST OF A SOIL WATER MODEL UNDER FIELD CONDITIONS,
Beese, F., Van der Ploeg, R.R., and Richter, W.
Goettingen University, Institute Soil Science and Forest Nutrition, (West Germany).
Soil Science Society of America Journal, Vol. 41, No. 5, p 979-984, September-
October, 1977. 4 fig, 2 tab, 27 ref.
Descriptors: *Soil water, *Unsaturated flow, *Evaporation, *Mathematical models,
On-site investigations, Model studies, Lysimeters, Moisture content, Soil water
movement, Soils, Soil properties, Precipitation (atmospheric), Rainfall, Drainage,
Subsurface drainage, Agriculture.
A 218-day experiment on a fallow loess soil was carried out to study infiltration
and redistribution under natural field conditions. On an experimental plot of 6
by 6 m, tensiometers were installed at 11 depths, 10, 20, 40, 60, 80, 100, 120, 140,
52
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160, 180, and 200 cm. The tensiometers were read at short irregular intervals
The precipitation was measured daily. The hydraulic functions of the layered,
horizontal soil and a relation between potential evaporation, actual evaporation,
and the soil suction at 5-cm depth had been established previously. With use of
these soil and atmospheric data, the unsaturated soil moisture flow equation was
solved numerically. The purpose of the numerical analysis was to determine if
the unsaturated soil moisture flow equation does describe observed soil moisture
behavior for such a long period. It was found that the calculated soil suction
values for all depths deviated less than 15% from the measured ones. It was con-
cluded that the unsaturated moisture flow equation can be a useful means to sup-
plement field measurements on infiltration, redistribution, evaporation, and in-
ternal drainage.
77:020-061
FLOW FROM A LINE SOURCE ABOVE A SHALLOW WATER TABLE,
Warrick, A.W., and Lomen, D,0.
Arizona University, Department of Soils, Water and Engineering, Tucson, Arizona
85721.
Soil Science Society of America Journal, Vol. 41, No. 5, p 849-852, September-
October, 1977. 3 fig, 1 tab, 8 ref.
Descriptors: Irrigation, Irrigation practices, Irrigation systems, Subsurface
irrigation, Hydraulic conductivity, Soil water, Soil water movement, Porous media.
An analytical solution is developed for a buried line source with an underlying
constant potential surface. The geometry is appropriate to describe flow from a
trickle or subsurface irrigation system of porous pipe or emitters spaced closely
in a line above a shallow water table or in a lysimeter. Assumptions include
steady-state conditions and a hydraulic conductivity exponentially related to the
pressure head. The soil water pressure head distribution is calculated for two
geometries one for which the water table dominates over the line source through-
out the flow medium, and a second for which most of the flow region is as if the
source were above an infinitely deep lower boundary.
77:026-062
TRACING THE TRANSFORMATIONS OF UREA FERTILIZER DURING LEACHING,
Wagenet, R.J., Biggar, J.W., and Nielsen, D.R.
Utah State University, Department of Soil Science and Biometeorology, Logan,
Utah 84322.
Soil Science Society of America Journal, Vol. 41, No. 5, p 896-902, September-
October, 1977. 8 fig, 5 tab, 22 ref.
Descriptors: Urea, Fertilizers, Fertilization, Nutrients, Leaching, Soils, Soil
investigations, Mathematical studies, Kinetics, Model studies, Nitrification,
Denitri fication.
The transport and transformation of urea, NH(4+), and NO(3-) in soil were math-
ematically described as functions of depth and time, subject to either steady
feed or pulse application of N, using relationships derived by assuming diffusion
and mass transfer as transport processes and first-order kinetics as a trans-
formational mechanism. The mathematical model was used to study the enzymatic
hydrolysis of urea, nitrification, and denitrification in laboratory soil columns.
Urea hydrolysis was found to be independent of initial urea concentration and the
02 concentration of the soil atmosphere. The rate of nitrification under transient
N conditions was found to be one order of magnitude greater than the rate of deni-
trification when there was 20% 02 in the soil atmosphere. Populations of nitri-
fiers were found to increase in response to successive applications of N,
77:02G-063
NITRATE DISSIMILATION AND POPULATION DYNAMICS OF DENITRIFYING BACTERIA DURING
SHORT TERM CONTINUOUS FLOW,
Volz, M.G., and Starr, J.L.
Department of Ecology and Climatology, and of Soil and Water, the Connecticut
Agricultural Experiment Station, New Haven, Connecticut.
Soil Science Society of America Journal, Vol. 41, No. 5, p 891-896, September-
October, 1977. 4 fig, 2 tab, 20 ref.
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Descriptors: Nitrates, Denitrification, Soils, Soil investigations, Nitrogen.
A solution containing 100 micrograms ml(-l) of N03(-) - N, 200 micrograms ml(-l)
of glucose-C, and 0..01N CaS04 was supplied continuously to soil in acrylic plastic
columns (6 cm inside diam. x 10 cm length) for up to 96 hours while N2 gas was
passed through the system. Concentrations of N03(-) - N in the effluent decreased
to 20 micrograms ml(-l) after 60 hours. Simultaneously, N02{-) - N concentrations
increased from traces to 65 micrograms ml(-l) and more than 70% of applied C had
been utilized after 60 hours. These results indicate that most C oxidation was
coupled with NO3(-) reduction although nearly all applied NO3(-) was ultimately
denitrified after 96 hours.
77:02G-064
HYDROLYSIS AND DECOMPOSITION OF CALCIUM MONTMORILLONITE,
Frenkel, H., and Suarez, D.L.
United States Department of Agriculture, Agricultural Research Service, United
States Salinity Laboratory, P.O. Box 672, Riverside, California 92502.
Soil Science Society of America Journal, Vol. 41, No. 5, p 887-891, September-
October, 1977. 3 fig, 2 tab, 12 ref.
Descriptors: Calcium, Montmorillonite, Clays, Leaching, Cation exchange.
The extent to which exchangeable calcium hydrolysis occurs during the preparation
of hoinoionic calcium montmorillonite clay and the rate of the reaction in distil-
led water at various suspension concentrations and levels of C02 was determined
at 25 degrees C. The rate and extent of hydrolysis was found to be comparable
to that reported for sodium montmorillonite and increased with C02 concentration.
CEC was appreciably reduced during washing of residual salts while preparing
calcium montmorillonite. The mechanism of hydrolysis is discussed.
77:02G-065
DRAINAGE FLUX IN PERMEABLE SOIL UNDERLAIN BY A COARSE-TEXTURED LAYER,
Clothier, B.E., Scotter, D.R., and Kerr, J.P.
Massey University, Department of Soil Science, Palmerston North (New Zealand).
Soil Science Society of America Journal, Vol. 41, No. 4, p 671-676, July-August,
1977. 9 fig, 13 ref.
Descriptors: *Hysteresis, *Lysimeters, *Model studies, Tensiometers, Drainage,
Hydraulics, Soil science. Equations, Mathematical studies, Water storage, Water
balance, Hydraulic conductivity.
Drainage from a permeable soil underlain by a coarse-textured layer was investi-
gated. Simplified theory was used to develop a model relating the drainage flux
at the base of the soil to the water storage in the soil. Despite significant
hysteresis in the water retentivity curve of the overlying soil and in the hy-
draulic conductivity-pressure potential relationship of the coarse layer, hystere-
sis had little effect on the storage-flux relation. The model successfully
simulated field drainage as measured by a lysimeter and field profile water
storage as found by neutron moisture probe measurements. The decline in the
drainage flux after the profile has been wetted depends on the depth and reten-
tivity of the soil and the hydraulic conductivity of the underlying coarse layer.
To use the model, only simple field measurements to find the storage-flux relation-
ship are needed.
77:02G-066
HOMOVALENT AND HETEROVALENT CATION EXCHANGE EQUILIBRIA IN SOILS WITH VARIABLE
SURFACE CHARGE,
Galindo, G.G., and Bingham, F.T.
California University, Department of Soil Science, Riverside, California.
Soil Science Society of America Journal, Vol. 41, No. 5, p 883-886, September-
October, 1977. 3 fig, 2 tab, 28 ref.
Descriptors: Cation exchange, Soils, Soil investigations. Sodium, Calcium,
Potassium, Magnesium, Adsorption.
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Cation-exchange equilibria involving K, Na, Ca, and Mg were studied with Chilean
Dystrandepts. The K-Na exchange and the Ca-Mg exchange showed that K and Ca were
preferentially adsorbed. Increased charge density through adsorption of phosphate
resulted in a reduction in the selectivity for K in the K-Na system. Phosphate
adsorption had no apparent effect on the selectivity for Ca in the Ca-Mg system.
In heterovalent systems these soils showed a perferential adsorption of the di-
valent cation. This selectivity was more pronounced at low equivalent concen-
tration of the divalent cation. The selectivity for the divalent cation increased
as the surface charge density was increased by phosphate adsorption.
77:02G-067
LEAD ADSORPTION BY MONTMORILLONITE USING A COMPETITIVE LANGMUIR EQUATION,
Griffin, R.A. , and Au, A.K.
Illinois State Geological Survey, Department of Geochemistry, Urbana, Illinois
61801.
Soil Science Society of America Journal, Vol. 41, No. 5, p 880-882, September-
October, 1977. 4 fig, 10 ref.
Descriptors: Adsorption, Lead, Heavy metals, Clays, Montmorillonite, Soil
properties, Soil chemical properties.
The adsorption of Pb from pure Pb(N03)2 solutions by Ca-montmorillonite at pH 5.00
and 25' degrees C was found to be sensitive to the weight of the clay sample. This
apparent sensitivity of the adsorption of Pb to the weight of the sample was at-
tributed to Ca competition for exchange sites as determined from Pb/Ca ratios
found in the solutions. Adsorption of Pb from O.lM Ca(Cl)4)2 solutions was sub-
stantially lower and was insensitive to the weight of the clay sample. This
further supported our conclusion that adsorption of Pb was dependent on the Pb/
Ca ratio.
77:02G-068
ABSENCE OF LOCAL EQUILIBRIUM DURING AMMONIUM TRANSPORT IN A SOIL COLUMN,
Ardakani, M.S., and McLaren, A.D,
California University, Department of Soils and Plant Nutrition, Berkeleyf
California 94720.
Soil Science Society of America Journal, Vol. 41, No. 5, p 877-879, September-
October, 1977. 3 fig, 1 tab, 9 ref.
Descriptors: Adsorption, Ammonium compounds, Soils, Soil, investigations. Soil
tests, Soil water movement, Sampling, Cation exchange.
Adsorption of HN4(+) from a stationary solution phase by a Hanford soil approached
an equilibrium state exponentially after about 30 minutes. By contrast, a local
equilibrium did not exist between NH4 (.+ ) in a moving solution phase and soil in a
column while a 77-ppm NH4(+) - N solution was delivered at a constant flow rate
for 26 days. Local equilibrium, however, was established when the downward solu-
tion flow was stopped by setting the column horizontally 1 hour before sampling.
Thus, the generality of the assumption of instantaneous equilibrium for cations
in moving soil solutions is questioned.
77:02G-069 '
DISSOLUTION OF ARSENIC FROM WATERLOGGED AND AERATED SOIL,
Hess, R.E., and Blanchar, R.W.
California University, Department of Soil Science, Riverside, California 925Q2.
Soil Science Society of America Journal, Vol. 41, No. 5, p 861-865, September-
October, 1977. 1 fig, 1 tab, 16 ref.
Descriptors: Arsenic, Soils, Soil investigations, Soil chemistry, Soil chemical
properties, Soil properties.
Sharpsburg and Menfro soils containing 320 and 160 micrograms As/g, respectively,
were waterlogged with water or 1% dextrose. The Eh reached a minimum of -150 mV
after 1 day of incubation and increased to about +300 mV after 12 days for both
soils in 1% dextrose. The Eh remained constant in the Sharpsburg soil during in-
cubation with water, but gradually decreased in the Menfro soil. In the 1% dex-
trose solution, As increased rapidly in both soils and became constant after 12
55
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days. The As in solution increased more slowly when incubated with water, but
also remained constant after 12 days. After freeze-drying and exposing the soil
to the atmosphere, Eh increased and As decreased to initial levels.
77:020-070
THE SHEAR RESISTANCE OF ROOT-PERMEATED HOMOGENEOUS AND STRATIFIED SOIL,
Waldron, L.J.
California University. Department of Soils and Plant Nutrition, Berkeley, California,
Soil Science Society of America Journal, Vol. 41, No. 5, p 843-849, September-
October, 1977. 8 fig, 3 tab, 17 ref.
Descriptors: Soils, Soil investigations, Root systems, Root development, Root
distribution, Cohesion, Alfalfa, Barley, Model studies.
Mechanical reinforcement which stabilizes soil on slopes has been attributed to
plant roots. To measure such reinforcement, direct shear tests were made on 25-
cm diameter root-permeated soil columns. Roots of alfalfa, barley, and yellow pine,
each increased the shear resistance of homogeneous and compacted layers of silty
clay loam at 30-cm depth. One-year-old alfalfa had a much greater reinforcing
effect than pine trees 16 months after transplanting or barley at its maximum
growth. Barley had a greater effect in the clay loam than pine, but its effective-
ness decreased as depth increased from 15 to 30 to 45 cm. Alfalfa roots were
more effective than either pine or barley roots in increasing the resistance to
shearing between a dense gravel-sand layer (simulating weathered rock) and the
overlying soil, increasing shearing resistance to as much as 5 times that of fal-
low soil. A model is presented of soil reinforced by nonrigid roots. Calculations
are given of slope safety factor increases from root reinforcement.
77:02G-071
EFFECT OF MOLE DRAINAGE ON SURFACE RUNOFF FROM A SOIL UNDER PASTURE,
Rennes, A., Tillman, R.W., Syers, J.K., and Bowler, D.G.
Massey University, Department of Soil Science, Palmerston North (New Zealand).
New Zealand Journal of Agricultural Research, Vol. 20, No. 1, p 45-49, February
1977. 2 fig, 2 tab, 12 ref.
Descriptors: Drainage, Drainage systems. Runoff, Pastures, Soil investigations,
Mole drains, Soil moisture, Rainfall, Infiltration, Sediments.
The effect of mole drainage on soil moisture and on the movement of water in sur-
face runoff from Tokomaru silt loam under pasture was investigated using two 80
sq m surface runoff plots each of 6 degrees slope. Frequently, particularly
during autumn and early winter, surface runoff was reduced on the drained site
by between 25 and 50% of that on the undrained site. However, mole drainage
was less effective in reducing surface runoff during prolonged rainfall, as in
wet winter periods. Under such conditions, there was a reduction both in the
differences between infiltration rates and in the infiltration rates themselves
for the drained and undrained sites. Regression and correlation analyses sug-
gested that soil moisture was a primary factor influencing surface runoff from
the undrained site. In contrast, rainfall intensity and duration were the primary
factors influencing surface runoff from the drained site. Greater amounts of
sediment were transported in surface runoff from the undrained plot and up to 95%
of this sediment was less than 63 micrometers in diameter. Mole drainage had a
pronounced effect in reducing the quantity of sediment transported.
77:02G-072
CURRENT TRENDS IN FIELD DRAINAGE PRACTICE,
Green, F.H.W.
Oxford University, Department of Agricultural Science, Parks Road, Oxford, 0X1
3PF, United Kingdom.
Journal of Environmental Management, Vol. 5, No. 3, p 207-213, July 1977. 5 fig,
5 ref.
Descriptors: Drainage, Drainage districts, Drainage engineer, Drainage practices,
Drainage systems, Drains, Runoff.
To supplement a previous article, particulars are given of current changes in
field drainage practice in England and Wales. Presentation is in the form of maps
with explanatory text, showing the regional variations in these changes.
5b
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77:02G-073
THE MONMOUTHSHIRE LEVELS' DRAINAGE SYSTEM: ITS ECOLOGY AND RELATION TO AGRICULTURE
Scotter, C.N.G., Wade, P.M., Marshall, E.J.P., and Edwards, RW
Wales University Institute of Science and Technology, Department of Applied Bioloqy,
Cardiff, S. Glamorgan, Wales.
Journal of Environmental Management, Vol. 5, No. 1, p 75-86 January 1977 7 fiq
2 tab, 22 ref.
Descriptors: Drainage, Drainage districts. Drainage effects, Drainage practices,
Drainage programs, Drainage systems, Agriculture, Crop production, Wildlife habi-
tats, Wildlife conservation, Wildlife.
The Gwent coastal plain or levels is principally an agricultural area. Its 8250
ha are dissected by 1407 km of drainage channels (reens). The type of agriculture
practiced, and realization of its full potential, are dependent upon the efficient
maintenance of the drainage system. The reens also harbour a rich aquatic flora
and fauna. This paper described the evolution of the drainage system, its manage-
ment and importance to the agriculture of the area. Possible conflicts between
progressively efficient agriculture, and the conservation of the reens as a valuable
wetland habitat are discussed.
77:02G-074
EXTENSION OF THE SIMILARITY HYPOTHESIS USED FOR MODELING THE SOIL WATER CHARACTER-
ISTICS,
Mualem, Y.
Colorado State University, Engineering Research Center, Fort Collins, Colorado.
Water Resources Research, Vol. 13, No. 4, p 773-780, August 1977. 13 fig, 14 ref.
Descriptors: *Soil water, *Hysteresis, *Soil moisture, *Model studies, Mathemati-
cal models, Soils, Wetting, Drying, Curves, Soil physics, Soil physical properties,
Soil science.
Two independent domains models were derived by using an extended similarity hy-
pothesis, according to which the pore water distribution function is interpreted
to be f(r,rho) = h(r)h(rho). When the hypothesis was applied to the Neel diagram
and the Mualem diagram, it yielded 2 different models which permit prediction of
the hysteretical relationship from only 1 branch of the main hysteresis loop. The
models yield an extremely simple formula for the relationship between the boundary
drying and wetting curves. Moreover, a universal nondimensional hysteresis was
derived for all soils. Comparison with experiments showed that the model which
used the Neel diagram fails to reproduce a reasonable shape of the hysteresis
curves. However, much better results were achieved by the second model, which
used the Mualem diagram. In some cases the predicted curves were in very good
agreement with the observed ones. For soils in which blockage against air entry
plays a significant role, the model is less efficient as a predictive tool. It
yields poor results in the region of high water content, while the predicted
curves are very close to the measured ones in the range of low water content.
77:026-07 5
MODELING INFILTRATION DURING A VARIABLE RAIN,
Chu, S.T.
South Dakato State University, Department of Agricultural Engineering, Brookings,
South Dakota 57007.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p. 1-14. 1 fig, 2 tab, 6 ref, 45 equ.
Descriptors: Model studies, Infiltration, Rainfall, Rainfall intensity, Rainfall-
runoff relationships.
The Green Ampt equation was modified to describe the infiltration process during
a rainfall event with variable intensities. A procedure was introduced to deter-
mine the volume of runoff and the distribution of rainfall excess.
57
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77:02G-076
AIR-EARTH INTERFACE CONCEPT FOR WIDE-RANGE CONTROL OF INFILTRATION,
Dixon, R.M.
United States Department of Agriculture, Agricultural Research Service, South-
west Rangeland Watershed Research Center, Tucson, Arizona.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p. 1-33. 11 fig, 1 tab, 28 ref.
Descriptors: Infiltration, Soil water movement, Simulation analysis, Soils,
Soil investigations.
The air-earth interface concept is formulated and discussed relative to experi-
mental verification, compatibility with Darcy-based infiltration theory, quanti-
fication for predictive purposes, and applicability to practical infiltration
control problems. This concept appears applicable to cultivated and uncultivated
soils, and to soils severely disturbed by road construction and strip mining.
77:02G-077
SOLUTE TRANSFER, WITH EXCHANGE BETWEEN MOBILE AND STAGNANT WATER, THROUGH
UNSATURATED SAND,
Gauden, J.P., Jegat, H., Vachaud, G., and Wierenga, P.J.
Centre National de la Recherche Scientifique, Paris (France).
Soil Science Society of America Journal, Vol. 41, No, 4, p 665-671, July-August,
1977. 6 fig, 2 tab, 22 ref.
Descriptors: *Solutes, *Transfer, *Ion exchange, Unsaturated flow, Diffusion,
Soils, Salinity, Depth, Leaching, Laboratory tests, Numerical analysis. Mathe-
matical models, Equations, Stagnant water, Calcium chloride.
Changes in salt concentration with time were measured at several depths inside
and at the exit of a 94-cm uniform unsaturated sand column which was leached at
steady rates with solutions of calcium chloride. Observed salt distributions
were compared with salt distributions calculated with a numerical procedure
which was based on the dead-end pore model of Coats and Smith (1964) . Values
for the dispersion coefficient, the diffusional mass transfer coefficient, and
the fraction mobile water used in the model were obtained at different water
contents by curve fitting observed and calculated concentrations at one depth.
The same values then were used to calculate salt distributions at other depths
and at the exit of the column and were compared with measured salt distributions.
Excellent agreement was obtained. The model presented a good description of the
extensive tailing of the salt concentration distributions observed inside and at
the exit of the column. The amount of stagnant water was found to increase with
decreasing water content from 4% of the total water content of 0.256 cu cm/cu cm
to 40% of the total water content at a water content of 0,200 cu cm/cu cm. The
apparent dispersion coefficient decreased from 6 sq cm/hour to 1 sq cm/hour at
water contents of 0.256 and 0.200 cu cm/cu cm, respectively.
77:02G-078
KINETICS OF SALT RELEASE FROM A SALINE SOIL,
Jurinak, J.J., Whitmore, J.C., and Wagenet, R.J,
Utah State University, Department of Soil Science and Biometeorology, Logan, Utah.
Soil Science Society of America Journal, Vol. 41, No. 4, p 721-724, July-August,
1977. 5 fig, 8 ref.
Descriptors: *Saline soils, *Utah, *Water quality, *Soil chemical properties,
*Leaching, *Salinity, *Kinetics, *Salts, Diffusion, Analytical techniques,
Percolation, Soil moisture. Soil water, Soil water movement, Physical properties,
Properties, Saline water.
The kinetics of salt release from simulated saline sediments were studied to ascer-
tain the potential of sediments as a diffuse source of salinity. Two rate equa-
tions were derived, both based on the premise that dissolution is a diffusion
controlled process. The equations were ln(l-C/C sub s) = -kt and C = k't(l/2),
where c is the concentration at any point in the bulk solution, c sub s is the
equilibrium concentration of the soluble soil minerals, t is time, k is the first-
order rate constant, and k' a proportionality constant. Kinetic data were
58
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obtained from a saline typic torriorthent soil derived from Mancos shale in the
Price River Basin, Utah. During the initial 72 hours of reaction, dissolution
can be described by three diffusion controlled reactions.
size decreased the rate of reaction.
fective in describing salt release.
Increasing particle
Both derived equations were equally ef-
77:026-079
EFFECT OF SOIL STRENGTH ON SOIL DETACHMENT DUE TO RAINDROP IMPACT,
Cruse, R.M. , and Larson, W.E.
Minnesota University, St. Paul, Minnesota.
Soil Science Society of America Journal, Vol. 41. No. 4 p 777-781 Julv-Auaust
1977. 7 fig, 3 tab, 18 ref .
Descriptors: *Raindrops, *Soil strength, *Impact (rainfall), Erosion, Shear
strength, Sheet erosion, Bulk density, Soils, Mathematical studies, Equations.
Soil strength was altered in 3 different ways to test the hypothesis that soil
splash from raindrop impact is related to soil strength parameters. Bulk density
changes were used to alter direct solid particle-to-particle contact; changes in
matric potential were used to change contact relationships between solid particles
and liquid films; and additions of polyvinyl alcohol (PVA) provided a direct
bonding mechanism between solid particles. The amount of soil detached by a
single simulated 4.8-mm raindrop falling from a height of 177 cm was correlated
closely with the shearing strength as measured by a triaxial compression test.
77:02G-080
ANALYSIS OF THE SATURATED-UNSATURATED HYDRAULIC CONDUCTIVITY IN A MIXED SODIUM-
CALCIUM SOIL SYSTEM,
Russo, D., and Bresler, E.
Volcanl Institute of Agricultural Research, Bet-Dagan (Israel) .
Soil Science Society of America Journal, Vol. 41, No. 4, p 706-710, July-August,
1977. 4 fig, 23 ref.
Descriptors: *Hydraulic conductivity, *Ions, *Sodium, *Calcium, Soils, Soil water
movement, Montmorillonite, Pore pressure, Pores, Porosity, Soil properties, Model
studies. Mathematical models, Soil science,
A model was developed to diagnose the effects of Na/sq rt of Ca ratios and soil
solution concentrations on the hydraulic conductivity for an unsaturated soil .
The model takes into account the porous nature and the electrical properties
of the soil. Interactions between ions in the exchange phase and in the liquid
phase were expressed quantitatively by the diffuse double-layer theory. Experi-
mental data on the effect of soil solution and soil water pressure on clay platelet
organization and structure were considered in the model. A test was made on the
sensitivity of the model to variations in the various input parameters , The model
was found to be sensitive to the relationship between the number of platelets per
clay particle and the ESP of the soil. The diagnostic model was compared with
experimental data for 3 soils of different texture. The model approximates the
hydraulic conductivity function for many practical combinations of Na/sq rt of
Ca ratios and soil solution concentrations for the ranges of soil water content
in which most of the water flow occurs.
77:O2G-081
EFFECT OF MIXED NA-CA SOLUTIONS ON THE HYDRAULIC PROPERTIES OF UNSATURATED SOILS,
Russo, D., and Bresler, E.
Volcani Institute of Agricultural Research, Bet-Dagan (Israel) .
Soil Science Society of America Journal, Vol. 41, No. 4, p 713-717, July-August,
1977. 6 fig, 1 tab, 20 ref.
Descriptors: *Sodium, *Calcium, *Soil properties, *Hydraulic properties. Soil
water, Unsaturated flow, Loam, Soils, Ion exchange, Diffusivity, Hydraulic con-
ductivity, Moisture content, Laboratory tests, Retention.
The effects of mixed Na-Ca solutions on soil water diffusivity and unsaturated
hydraulic conductivity were tested for a loamy soil from Gilat, Israel. s°il
water diffusivity functions, D(theta), were determined by the horizontal infil-
tration method. Unsaturated hydraulic conductivity functions, K(theta), were
59
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determined both directly (by vertical infiltration for suction heads of 0-50
cm H20) and indirectly (from diffusivity functions and soil water retention
curves). Prior to determinations, soil samples were equilibrated with solu-
tions containing a given concentration and composition of Ca and Na . The re-
sults showed that D(theta) and K(theta) are independent of solution concentra-
tions in a Ca-saturated system. In mixed Na-Ca systems, hydraulic conductivity
and soil water diffusivity functions are highly dependent on the composition
and concentration of the soil solution, in addition to their dependence on soil
water content, theta. For any given theta, both K(theta) and D(theta) decrease
as either soil solution concentration decreases or the sodium fraction in the
soil solution increases. The negative effect of a combination of high Na-to-
Ca ratio and low soil solution concentration on K(theta) is related directly
to the degree of water saturation of the soil. Low values of theta can com-
pensate for the negative effects of high Na-to-Ca ratio and low solution con-
centration .
77:026-082
CHISELING INFLUENCES ON SOIL HYDRAULIC PROPERTIES,
Allmaras, R.R., Rickman, R.W., Ekin, L.G., and Kimball, B.A.
Agricultural Research Service, Columbia Plateau Conservation Research Center,
Pendleton, Oregon.
Soil Science Society of America Journal, Vol. 41, No. 4, p 796-803, July-August,
1977. 7 fig, 2 tab, 26 ref.
Descriptors: *Chiselling, *0regon, *Washington, *Soil water, *Infiltration,
*Hydraulic conductivity, Cultivation, Soil properties, Silts, Loam, Cation
exchange, Clays, Organic matter, On-site investigations, Bulk density, Depth,
Moisture content, Drainage, Evaporation, Hydraulic properties.
Hydraulic conductivity (K) and soil water desorption characteristic (SWDC) were
field measured in the 120-cm soil profile of a Walla Walla (Mesic type Haploxe-
roll) silt loam before and after chiselling 43-cin deep. The test Walla Walla
soil is layered. Chiselling affected both the SWDC and K in the upper 30 cm,
especially at 10 and 20-cm depths, but had no influence on the measurements
at increased, especially in the -50 to -300 mbar range. Failure of chiselling
to improve water relations in the mild duripan extending from 30 to 45 cm sug-
gests the need for addition of plant residue or chemical amendments into the
chisel slots. Water contents and hydraulic heads during drainage showed that
chiselling could reduce evaporation by reducing water content and diffusivity.
Overall soil profile hydraulic resistances showed relative average K up to 15
times greater as a result of chiselling 43 cm deep, but nearly similar accele-
rated internal drainages were projected for simulated chiselling to 25-cm depth
vs. chiselling to 43 cm.
77:02G-083
A LABORATORY TECHNIQUE FOR APPRAISING IN SITU SALINITY OF SOIL,
Mubarak, A., and Olsen, R.A.
Montana State University, Department of Chemistry, Bozeman, Montana,
Soil Science Society of America Journal, Vol. 41, No. 5, p 1018-1020, September-
October, 1977. 2 fig, 2 tab, 14 ref.
Descriptors: *Saline soils, *Salinity, *Electrical conductance, *Laboratory
tests, Centrifugation, Chemistry, Salts, Analytical techniques, Soils, Soil
properties, Immiscibility, Soil science, Soil solutions, Dilution effects.
A laboratory technique was devised for removal of solution from soils at field
water content. A soil sample can be placed directly in a closable centrifuge
tube, thereby minimizing changes which could be induced by altering gaseous
equilibria. Water need not be added to the soil sample, so changes in electrical
conductivity (EC) and in concentration of species present are avoided. The soil
solution was obtained from the sample by immiscible displacement with carbon
tetrachloride using centrifugation. The technique is simple and relatively
rapid. Values for EC in successively displaced solution samples from a given
soil sample were found to be essentially constant. The values for EC obtained
for an assortment of soils were significantly higher than those obtained using
2:1 or saturation extracts but were well correlated with them.
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77:020-084
THE SOLUBILITIES OF CARBONATES AND PHOSPHATES IN CALCAREOUS SOIL SUSPENSIONS
Marion, G.M., and Babcock, K.L. '
Weyerhaeuser Forestry Research Center, 505 North Pearl Street, Centralia
Washington 98531. '
Soil Science Society of America Journal, Vol. 41, No. 4, p 724-728, July-Auqust
1977. 4 fig, 6 tab, 36 ref, 2 equ.
Descriptors: Soils, Soil investigations. Carbonates, Phosphates, Ions, Soil
chemistry.
Previously reported discrepancies between measured soil carbonate and phosphate
activity products and the solubility products of pure crystalline minerals may,
in part, be attributable to the incomplete characterization of ion-pairs in
solution. Up to 50 percent of the soluble P04 and significant amounts of Ca,
Mg, and S04 were present as ion-pairs. Ignoring ion-pairs resulted in signifi-
cant differences in calculated activity products for both carbonates and phos-
phates. One soil was undersaturated and two were supersaturated with respect
to calcite. Calcite was the only carbonate mineral identified by X-ray diffrac-
tion measurements. Calcium carbonate activity products were highly correlated
to Mg activities. Magnesium-calcite apparently controlled the solubility of
soil carbonate. The soil phosphate activity products fell between the solubility
products of octacalcium phosphate and hydroxyapatite. The phosphate solubility
data were compatible with, but not proof of, the presence of calcium phosphate
minerals in soils.
77:02G-085
OXIDATION OF ELEMENTAL SULFUR IN SOILS,
Nor, Y.M., and Tabatabai, M.A.
Sains Malaysia University, School of Biological Sciences, Penang, Malaysia.
Soil Science Society of America Journal, Vol. 41, No. 4, p 736-741, July-August,
1977. 5 fig, 4 tab, 25 ref.
Descriptors: Oxidation, Sulfur, Soils, Soil investigations, Soil chemistry.
Studies of oxidation of elemental S in soils showed that thiosulfate and tetra-
thionate are produced during S oxidation in soils. In this work, unamended and
elemental S-amended soils were incubated (30 degrees C) under aerobic conditions
for various times. The amounts of S203-, S406-, and S04-S produced during in-
cubation were determined. Results showed that S203(2-) was produced within the
first few days of incubation and that S406(2-) accumulated in some soils. The
rate of S oxidation increased with increasing incubation temperature (5, 15,
and 30 degrees C) and with increasing the rate of S application (50, 100, and
200 micrograms S/gram soil). For 100 micrograms S/gram soil, the rates of oxi-
dation of elemental S in 10 Iowa surface soils ranged from 39 to 75 micrograms
S/gram soil after incubation at 30 degrees C for 70 days; rates were more rapid
in alkaline soils than in acid soils. There was little change in pH of soils
even when the S application rate was increased from 50 to 200 micrograms S/gram
soil. The rate of S oxidation was lower in air-dried soils than in field-moist
soils.
77:02G-086
ADSORPTION OF ZN BY FE AND AL HYDROUS OXIDES AS INFLUENCED BY AGING AND PH,
Shuman, L.M.
Georgia University Agricultural Experiment Station, Experiment, Georgia 30212,
Soil Science Society of America Journal, Vol. 41, No. 4, p 703-706, July-August,
1977. 4 fig, 1 tab, 15 ref.
Descriptors: Adsorption, Zinc, Iron.
Zinc solutions were equilibrated with both fresh and aged Fe and Al hydrous oxides
to measure Zn adsorption. The data conformed to the Langmuir isotherm and the
Langmuir coefficients for Zn adsorption capacities and bonding energies were de-
termined. The adsorption capacities for the aged Fe oxide (geothite) and the aged
Al oxide (gibbsite) were the same. The adsorption capacities for both of the
fresh oxides (amorphous) were about 10 times those for the aged oxides which cor-
responded to a 10-fold difference between their respective CEC's and surface areas.
61
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The bonding energies for Zn for the fresh Al oxide were three times that for the
fresh Fe oxide but the bonding energies for the two aged oxides were the same.
Bonding energies were directly related to adsorption capacities. The inflection
points on the Zn adsorption vs. pH curves were between pH 5 and 6 for both oxides.
77:02G-087
SOIL TYPES AND INFILTRATION/WATER MOVEMENT,
Bree, J.
Agrifim Irrigation, Incorporated, 6948 Arrowwood Drive, Modesto, California 95355.
Drip/Trickle Irrigation, Vol. 2, No. 2, p 18-19, 29, March-April, 1977. 2 fig,
1 tab.
Descriptors: Irrigation systems, Irrigation practices, Soils, Infiltration, Soil
water. Soil water movement, Soil moisture, Irrigation design.
With drip irrigation, watering the crop rather than the soil is discussed. How-
ever, soils are of major importance to the agronomist, because they are his pri-
mary concern in the selection of equipment and the design of a drip/trickle system.
77:02G-088
INFLUENCE OF EXCHANGEABLE CATION ON THE SORPTION OF TRACE AMOUNTS OF CADMIUM BY
MONTMORILLONITE,
Garcia-Miragaya, J., and Page, A.L.
Institute Venezolano de Investigaciones Cientificas, Centro de Ecologia, Apdo 1827,
Caracas 101, Venezuela.
Soil Science Society of America Journal, Vol. 41, No. 4, p 718-721, July-August,
1977. 2 fig, 2 tab, 20 ref.
Descriptors: Cation exchange, Sorption, Cadmium, Clays, Soil water. Soil moisture.
The effect of different exchangeable cations on the sorption of trace amounts of Cd
by montmorillonite (clay fraction, Upton, Wyoming) was studied by equilibrating
samples of homoionic clay suspensions with CdC12 solutions ranging from 15 to 120
micrograms Cd/liter. These Cd concentrations are similar to those found in natural
and contaminated soil-water systems. The amount of Cd sorbed on the montmorillonite
surfaces depended on the kind of exchangeable cation, decreasing in the order Na-
montmorillonite > K-montmorillonite > Ca-montmorillonite > Al-montmorillonite.
Exchangeable Al was found to be particularly effective in reducing Cd sorption by
high energy sites on montmorillonite.
77:02G-089
EFFECT OF INORGANIC AND ORGANIC COMPOUNDS ON THE EXTRACTABILITY OF 239PU FROM AN
ARTIFICIALLY CONTAMINATED SOIL,
Nishita, H., Haug, R.M., and Rutherford, T.
California University, Laboratory of Nuclear Medical and Radiation Biology, Los
Angeles, California.
Journal of Environmental Quality, Vol. 6, No. 4, p 451-455, October-December,
1977. 1 fig, 4 tab, 32 ref.
Descriptors: Soils, Soil investigations, Organic matter, Soil tests, Soil pro-
perties, Soil chemistry.
The effect of a number of inorganic and organic compounds on the extractability of
239Pu from a contaminated soil has been examined. This has been done on an arti-
ficially contaminated kaolinitic soil by using the equilibrium batch method of ex-
traction. Among the 21 inorganic compounds examined, NaHP04 showed the least 239Pu
extractability (0.07% of dose) and Na4P207 showed the greatest extractability
(28.59% of dose). The compounds that showed relatively high 239Pu extractability
included NaF, Na2B407, Na4P207, Na2C03, Na202, NaOH, and NH40H. Among the organic
compounds, the order of 239Pu extractability was Na acetate less than Na formate
less than Na oxalate less than Na tartrate less than Na citrate. A 0.004M DTPA
solution was a more effective extractant than a 0.08M citric acid solution. Aside
from the chemical nature of these compounds, the 239Pu extractability was influ-
enced by soil and extractant pH, soil organic matter, equilibrium time, soil weight/
extractant volume ratio, and wet-dry pretreatment of the soil.
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77:020-090
ABIOLOGICAL METHYLATION OF MERCURY IN SOIL,
Rogers, R.D.
United States Environmental Protection Agency, Monitoring and Support Laboratory,
Office of Research and Development, Las Vegas, Nevada 89114.
Journal of Environmental Quality, Vol. 6, No. 4, p 463-467, October-December, 1977
3 fig, 3 tab, 11 ref.
Descriptors: Soils, Soil investigations, Heavy metals, Mercury, Organic matter,
Soil chemistry -
The results from this work define several factors influencing the methylation of
mercuric ion in soil. Two of the most important findings were that it is possible
to extract the mercury methylating factor from soil with a solution of 0.5N sodium
hydroxide (NaOH) and that this factor is responsible for the abiological methyla-
tion of Hg in the soils under investigation. The ability of the soil extract to
methylate Hg is influenced by temperature, mercuric ion concentrations, and solu-
tion pH. In addition, it was found that the methylating ability of the soil ex-
tract was stable at high temperatures (121C), but was lost after exposure to
ultraviolet radiation.
77:020-091
TEMPERATURE GRADIENT EFFECTS ON IN SITU HYGROMETER MEASUREMENTS OF WATER POTENTIAL,
Wiebe, H.H., Brown, R,W., and Barker, J.
Utah State University, Department of Soil Science, Logan, Utah 84322.
Agronomy Journal, Vol. 69, No. 6, p 933-939, November-December, 1977. 6 fig, 1 tab,
17 ref.
Descriptors: Temperature, Hygrometry, Soil water, Soil moisture, Soil properties,
Soils.
The effects of temperature gradients on water potential measurements with various
commercial and laboratory soil hygrometers were tested in a soil column at -18
bars or in a sponge column wetted with a -18 bar sodium chloride solution. Tem-
perature gradients were induced in the medium by warming or cooling either the
base or the top of the column for several hours. Hygrometers in which the mea-
suring (wet) junction was located in the middle of the cylindrical sample surface
gave small temperature gradient errors, less than 3 bars when the temperature
gradient in the surrounding medium was 1 degree cm(-l). Locating the measuring
thermocouple near the base of the cylindrical sample surface gave errors ranging
from 10 to 18 bars per gradient for 1 degree cm(-l). Hygrometers with an "end
window" sample surface gave errors ranging from 23 to 62 bars. Water potential
readings were consistently too low (dry) when the sample surface was cooler than
the measuring junction, and too high (near zero) when the sample surface was
warmer. Accurate water potentials were obtained with all models when medium tem-
perature was uniform.
77:02G-092
THE MINIMUM SIZE OF PERMEABLE FILL USED WITH MOLE DRAINAGE,
Dennis, C.W., and Groote, S.G.
Ministry of Agriculture, Field Drainage Experimental Unit, Fisheries and Food,
Anstey Hall, Trumpington, Cambridge, Great Britian.
Agricultural Water Management, Vol. 1, No. 2, p 143-153, September 1977. 7 fig,
1 tab, 6 ref.
Descriptors: Mole drainage, Drainage engineering, Drainage practices. Drainage
systems. Drains, Hydraulic conductivity.
Laboratory work involving the full scale simulation of flow from a mole drainage
channel into a trench filled with permeable material and thence to the pipe drain
at the bottom of the trench is described. Four sizes of permeable fill, two trench
widths, two pipe types and a wide range of flow rates were used in the investiga-
tions. Provided that there was reasonable vertical separation between the mole
channel and pipe the flow could be divided into three distinct phases namely;
entry from the mole channel, near vertical flow within the permeable fill_and
entry into the pipe. The most limiting of these was the ability of the fill to
accept water from the mole channel. Variation of hydraulic head with flow rate
63
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and permeable fill size at critical points of the system is presented in graphical
form. It is suggested that permeable fill with a mean diameter of 5 mm is the
minimum size acceptable under United Kingdom conditions and that this result will
not be affected by the presence of a small quantity of fine material. The hydrau-
lic conductivity associated with such material, in the absence of fines, is ap-
proximately 2500 m/day- Application of the data to other design conditions is
also possible.
77:02G-093
PARAMETER ESTIMATION OF THE GREEN AND AMPT INFILTRATION EQUATION,
Brakensiek, D.L., and Onstad, C.A.
United States Department of Agriculture, Agricultural Research Service, Northwest
Watershed Research Center, Boise, Idaho 83701.
Water Resources Research, Vol. 13, No. 6, p 1009-1012, December 1977. 2 fig, 5 tab,
10 ref, 4 equ.
Descriptors: Infiltration, Soil water, Soil water movement, Watersheds, Runoff,
Hydrology.
Infiltrometer data are utilized to test a fitting procedure for the Green and Ampt
infiltration equation parameters. The spatial variation of the estimated para-
meters is averaged to give lumped parameter values for watershed modeling. An ap-
propriate scale for parameter averaging is discussed, which transforms parameter
values to normal deviates. A sensitivity analysis for the equation parameters is
performed for both infiltration estimates and runoff hydrograph volume and peak
rates. The capillary pressure parameter shows least sensitivity; however, varia-
tion in the tillable porosity and effective conductivity parameters has a major
influence on infiltration and runoff amounts and rates.
77:02G-094
INFLUENCE OF THE HYSTERESIS EFFECT ON TRANSIENT FLOWS IN SATURATED-UNSATURATED
POROUS MEDIA,
Hoa, N.T., Gaudu, R,, and Thirriot, C.
Institute of Fluid Mechanics, Toulouse, France.
Water Resources Research, Vol. 13, No. 6, p 992-996, December 1977. 5 fig, 7 ref,
2 equ.
Descriptors: Hysteresis, Saturated flow, Porous media, Soil water, Soil water
movement, Unsaturated flow, Simulation analysis.
In the following report the authors experimentally and numerically study one-
and two-dimensional transient flows where the hysteresis of the relationship
of suction-water content clearly appears. In the numerical simulation of these
flows, by using a finite element method, the hysteresis effect is taken into ac-
count by considering both its primary and secondary scanning curves; when the
seepage surface occurs, it too is taken into account. The comparison with ex-
perimental results shows that in the concerned problems a numerical simulation
in which this hysteresis effect is ignored may .involve important errors.
77:02G-095
INFILTRATION FORMULA BASED ON SCS CURVE NUMBER,
Aron, G., Miller, A.C., Jr., and Lakatos, D.F.
Pennsylvania State University, Department of Civil Engineering, University Park,
Pennsylvania.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR4, Proceedings Paper 13427, p 419-427, December 1977.
3 fig, 4 tab, 9 ref.
Descriptors: *Infiltration, *Rainfall-runoff relationships, *Runoff, *Model
studies, Soils, Storms, Urbanization, Equations, Curves, Permeability, Storage
capacity, Soil water, Urban runoff, Differentiation.
A formula was developed for computing infiltration in rainfall-runoff simulations
from published Soil Conservation Service (SCS) soils data. Cumulative infiltra-
tion was treated as the difference between cumulative rainfall and runoff. The
SCS runoff formula then was differentiated with respect to precipitation to
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77:02G-096
PROTECTION OF A UNIQUE ECOLOGICAL AREA THROUGH IMPROVED WATER AND FERTILITY
MANAGEMENT,
Fischbach, P.E.
Nebraska University, Department of Agricultural Engineering, Lincoln, Nebraska.
Available from the National Technical Information Service, Springfield, Virginia
22161 as PB-274 399- University of Nebraska Water Resources Center, Completion
Report, October 2, 1977. 187 p, 68 fig, 43 tab, 7 ref, 4 append.
Descriptors: *Water management (applied), *Soil properties, *Nitrogen, *Water
utilization, *Nitrates, *Leaching, *Fertilization, *Nebraska, Model studies,
Irrigation, Sands, Corn (field), Soil water, Moisture deficit, Evapotranspiration,
Percolation, Rainfall, Fertilizers, Crop production, Soil-water-plant relation-
ships.
Research was conducted to define practices for managing water and nitrogen ferti-
lizer in the production of irrigated corn on sandy soils. The objective was to
increase the efficiency of use of the water resource while minimizing the leaching
of nitrate nitrogen from the crop root zone to the groundwater system. On the
sandy soils which were studied, experiments showed that it is not necessary to
completely replenish the soil water deficit at each irrigation. Near maximum
yields were obtained when water application was limited to an amount equivalent
to .76 cm per day, approximately 60% of the peak evapotranspiration rate. Stored
soil water and rainfall supplemented irrigation application. Percolation loss
was minimized by this technique. An irrigation frequency of 3.5 days during July
and August produced greater yields than did frequencies of 1.5 or 7 days. Research
indicated that the present farmer practice of applying 250 kg/ha of nitrogen and
completely replenishing the soil water deficit at each irrigation may result in
nitrate leaching losses of 30 to 45 kg/ha during the growing season, depending on
rainfall amount.
77:02G-097
COLORIMETRIC DETERMINATIONS OF EXCHANGEABLE AMMONIUM, UREA, NITRATE, AND NITRITE
IN A SINGLE SOIL EXTRACT,
Onken, A.B., and Sunderman, H.D.
Texas A and M University, Agricultural Experiment Station, Agricultural Research
Extension Center, Lubbock, Texas.
Agronomy Journal, Vol. 69, No. 1, p 49-53, January-February, 1977, 10 tab, 9 ref.
Descriptors: Ammonium, Urea, Nitrates, Nitrites, Fertilizers, Soils, Soil investi-
gations. Soil tests.
Interest in N transformations in soils has increased greatly in recent years,
particularly with increased use of urea-containing fertilizers. However, only
one procedure for determination of exchangeable ammonium, nitrate, nitrite, and
urea in a single soil extract has been proposed and it requires the use of both
distillation and colorimetric equipment. It would be useful to have a set of
colorimetric procedures for the determination of these N forms in a single ex-
tract. Previous research indicated sodium sulfate, as an extractant,,would be
least likely to produce unwanted interferences in these procedures. Thus, re-
search was initiated to determine (i) if Na2S04 could be used as an extractant
for exchangeable NH4+, N03-, NO2- and urea and (ii) necessary modifications to
make desirable colorimetric procedures usable in a Na2S04 extraction system.
77:026-09 8
EFFECT OF SELECTIVE DISSOLUTION, ELECTROLYTES, AERATION, AND STERILIZATION ON
TECHNETIUM-99 SORPTION BY SOILS,
Landa, E.R., Thorvig, L., and Cast, R.G.
Oregon State University, Department of Soil Science, Corvallis, Oregon 97331.
Journal of Environmental Quality, Vol. 6, No. 2, p 181-187, April-June, 1977.
7 fig, 2 tab, 24 ref.
65
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Descriptors: Soils, Soil investigation, Sorption, Soil chemistry, Soil chemical
properties, Anion exchange, Organic matter.
The objective of this study was to determine the extent that technetium-99, a
long-lived beta-emitting radionuclide, might be sorbed from aqueous solution
by 11 well-characterized soils, and to elucidate the sorption mechanisms involved.
About 98% of the added 99Tc was sorbed within a period of 2 to 5 weeks by 8 of the
11 soils. The slow kinetics observed and the removal of trace quantities of 99Tc
from solution in the presence of large amounts of chloride and phosphate tend to
rule out anion exchange as the sorption mechanism. The lack of sorption exhibited
by the low organic matter soils, the reduction in sorption following H202 digestion
of the soil, and the high recoveries of sorbed 99Tc on extraction with NaOH suggest
a role for the living and/or nonliving organic fraction of the soil. Sterilization
of previously sorbing soils eliminated the sorption ability, indicating a micro-
bial role in the process. Results of aeration experiments were ambiguous but
suggest that anaerobic conditions are not a prerequisite for 99Tc sorption by soils.
77-.02G- 099
DECOMPOSITION OF RICE STRAW IN SOILS AS AFFECTED BY SOME MANAGEMENT FACTORS,
Sain, P-, and Broadbent, F.E.
California University, Department of Land, Air, and Water Resources, Davis, Cali-
fornia 95616.
Journal of Environmental Quality, Vol. 6, No. 1, p 96-100, January-March, 1977.
6 fig, 3 tab, 18 ref.
Descriptors: Rice, Decomposing organic matter, Soils, Soil investigations, Labora-
tory tests, Nitrogen, Phosphorus, Soil properties. Sulfur,
Decomposition of rice straw contained in nylon bags was measured in field experi^
ments at two different locations during winter and spring months. Incorporated
straw decomposed more rapidly than did straw on the soil surface, and least
decomposition occurred in straw samples suspended above the soil surface as in a
windrow. Decomposition rates were not affected by chopping straw. Laboratory
decomposition experiments conducted at 8 and 25C and at 60 and 150% water holding
capacity showed more effect of low temperature in retarding straw decomposition
than excess water. Additional nitrogen stimulated straw decomposition in Stock"
ton adobe clay during the first few weeks but had little effect in Sacramento
clay. After 2 months' initial decomposition the soil samples treated with straw
were dried and rewetted to 60% water holding capacity (WHC), then incubated another
2 months. During this period straw decomposition in Sacramento clay samples
which had received additional N was significantly depressed. Additional P and
S had no effect on rice straw decomposition.
77:02G-lQO
MASSIVE ACCUMULATION OF CALCIUM CARBONATE AND ITS RELATION TO NITROGEN FIXATION
OF SAINFOIN,
Ross, W.D., and Delaney, R.H.
Wyoming University, Plant Science Division, Laramie, Wyoming 82071,
Agronomy Journal, Vol. 69, No. 2, 0 242-246, March^April, 1977. 2 fig, 3 tab,
25 ref.
Descriptors: Lagoons, Calcium carbonate, Nitrogen, Soils, Soil investigations.
Sainfoin has many desirable qualities as a legume forage, but it is not widely
grown because of its lack of persistence and poor N-fixation on many sites. The
effect of competition by non-N-fixing soil microorganisms on N*-fixation was
studied at 0, 50, 80, 95, and 100% levels of autoclaved soil sterilization.
Plants were grown aseptically for 30 days, dipped in Rhizobium inoculum, and
transplanted to the sterilized soil. After 47 and 87 days in the growth chamber
at 24/18 C, the plants were harvested. Nitrogen fixation was determined by the
acetylene reduction capacity of the complete root system. Unexpectedly, root
distortion accompanied by massive accumulation of CaCO3 was stimulated in sain-
foin roots that were grown in autoclaved soil to reduce the soil microorganisms.
The purpose of the data presented is to describe the accumulation of Ca and its
affect on N-fixation in sainfoin.
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77:02G-101
ANION MOBILITY IN SOILS: RELEVANCE TO NUTRIENT TRANSPORT FROM TERRESTRIAL
TO AQUATIC ECOSYSTEMS,
Johnson, D.W., and Cole, D.W.
Washington University, College of Forest Resources, Washington,
Publication No. EPA-600/3-77-068, June 1977. 27 p, 8 fig, 1 tab,. 5Q ref, 1 append.
Descriptors: Nutrients, Soil chemistry, Ions, Anions, Adsorption, Leaching,
Model studies.
Nutrient transport from terrestrial to aquatic ecosystems is strongly mediated
by soil chemical interactions. Ions deposited on or biologically released with-
in the soils can enter into a variety of exchange and precipitation reactions
prior to (or instead of) entering aquatic ecosystems. This report reviews the
current knowledge of soil anion adsorption reactions and their effects on leach-
ing, and suggests a simple model, based on anion production and adsorption
considerations, to predict and explain nutrient transport. The relationship
of this approach to that based on cation production and adsorption is discussed,
77:02G-102
PLUTONIUM UPTAKE BY PLANTS FROM SOIL CONTAINING PLUTONIUM 238 DIOXIDE PARTICLES,
Brown, K.W., and McFarlane, J.C.
Monitoring Systems Research and Development Division, Environmental Monitoring
and Support Laboratory, Las Vegas, Nevada 89114.
Publication No. EPA-600/3-77-052, May 1977. 13 p, 3 fig, 2 tab, 21 ref.
Descriptors: Alfalfa, Vegetables, Crop production, Soil investigations, Plutonium,
Soil chemistry.
Three plant species--alfalfa, lettuce, and radisheswere grown in soils contami-
nated with plutonium-238 dioxide (238Pu02) at concentrations of 23, 69, 92, and
342 nanocuries per gram (nCi/g). The length of exposure varied from 60 days for
the lettuce and radishes to 358 days for the alfalfa. The magnitude of plutonium
incorporation as indicated by the discrimination ratios for these species, after
being exposed to the relatively insoluble Pu02r was similar to previously reported
data using different chemical forms of plutonium. Evidence indicates that the pre-
dominant factor in plutonium uptake by plants may involve the chelation of pluton-
ium contained in the soils by the action of compounds such as citric acid and/or
other similar chelating agents released from the plant roots.
77:02G-103
FIELD MEASUREMENT OF DENITRIFICATION,
Rolston, D.E., and Broadbent, F.E.
California University, Department of Land, Air and Water Resources, Davis, Cali-
fornia 95616.
Publication No. EPA-600/2-77-233, November 1977. 75 p, 40 fig, 15 tab, 13 ref.
Descriptors: Denitrification. Leaching, Return flow, Water quality, Irrigation,
Irrigation effects, Nitrogen, Nitrification, Nitrates.
The proportion of volatile products and rates of denitrification as influenced by
field-soil environmental conditions can only be ascertained by measuring the flux
of the gases produced. A thorough, quantitative evaluation of the rate and mag-
nitude of denitrification, leaching, and plant uptake provides a means for making
management decisions to control irrigation return flow water quality-
77:02G-104
IMMOBILIZATION OF FERTILIZER NITRATE APPLIED TO A SWELLING CLAY SOIL IN THE FIELD,
Kissel, D.E., Smith, S.J., Hargrove, W.L,, and Dillow, D.W.
Texas Agricultural Experiment Station, Temple, Texas 76501.
Soil Science Society of America Journal, Vol. 41, No. 2, p 346-349, March-April,
1977. 2 fig, 1 tab, 18 ref.
Descriptors: Nitrogen, Fertilizers, Fertilization, Nutrients, Crop production,
Soil properties, Soil texture, Crop response, Immobilization, Sorghum, Clays,
Nitrogen, Soil temperature.
b/
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Low recoveries of N fertilizer by crops on Houston Black clay prompted this in-
vestigation. Our objectives were to determine how much fertilizer nitrate can
be biologically immobilized under field conditions when fertilization exceeds
crop requirements and to determine when immobilization occurs during the growing
season. Calcium nitrate tagged with 9.6 atom % 15N was applied to field micro-
plots at 328 kg N/ha and grain sorghum was planted in rows across each microplot.
The various components of the N balance were measured by sampling microplots
at different times during the season. Only 2.1 kg N/ha was immobilized during
the first 47 days after fertilization and planting. The rate of immobilization
increased rapidly during the next 60 days and an additional 60 kg N/ha was
immobilized. This increase was apparently in response to an increase in soil
temperature above 22 C.
77:02G-105
ASSESSING TWO DIAGNOSTIC METHODS FOR ENUMERATION OF NITRATE REDUCING AND DENI-
TRIFYING BACTERIA IN SOIL-PLANT ROOT ASSOCIATIONS,
Volz, M.G.
Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504.
Soil Science Society of America Journal, Vol. 41, No. 2, p 337-340, March-April,
1977. 4 tab, 14 ref.
Descriptors: Nitrates, Denitrification, Bacteria, Soils, Soil investigations,
Soil chemistry, Fertilizers, Fertilization, Tomatoes, Soybeans, Corn.
Most probable number (MPN) determinations were made of NO3(-} reducing-and
denitrifying bacteria in soil samples taken at time of crop harvest from fallow
sites and from root zones of fertilized field plots of tomato, soybean or corn
plants cultivated in pure stand or in association with nutsedge, a competitve
weed. Diagnostic methods utilized were inoculated Difco N03(-) broth and Giltay's
medium (citrate-nitrate-asparagine + mineral salts), incubated with and without
the exclusion of atmospheric 02, respectively. The N03C-) broth method usually
yielded both numerically larger and significantly different (5% level) MPNs for
N03(-) reducers (5 of 7 cases larger, 3 significant) and denitrifiers (6 of 7
cases larger, 3 significant) from a given soil inoculum when compared with identi-
cal enumerations performed with Giltay's medium.
77:02G-106
INFLUENCE OF PH ON THE SORPTION OF C0(2 + ), ZN(.2+) AND CA(2 + ) BY A HYDROUS MANGA-
NESE OXIDE,
Loganathan, P., Burau, R.G., and Fuerstenau, D,W.
Coconut Research Institute, Lunuwila, Sri Lanka.
Soil Science Society of America Journal, Vol. 41, No. 1, p 57-62, January-February,
1977. 7 fig, 1 tab, 15 ref.
Descriptors: Sorption, Soil chemistry, Soil investigations, Soil chemistry pro-
perties, Calcium, Cations, Adsorption, Ion exchange.
The uptake of Co2(+), Zn2(+), and Ca2(+) by delta-Mn02 at 24.0 ± 0,5 C as a function
of pH and salt concentration was investigated. At pH values <5, delta-Mn02 re-
leased structural Mn to solution phase during the sorption of Co2(+) and to a les-
ser extent during Zn2(+) sorption. Calcium sorption did not release any Mn to
solution phase. In addition, C02(+), Zn2(+), and Ca2(+) were shown to adsorb
specifically at the delta-Mn02 surface by exchange with bound H, The pH values
had very little influence on the sorption of these cations.
77:02G-lQ7
ON THE CHEMICAL FOUNDATION OF THE SODIUM ADSORPTION RATIO,
Sposito, G., and Mattigod, S.V.
California University, Department of Soil and Environmental Sciences, Riverside,
California 92521,
Soil Science Society of America Journal, Vol. 41, No. 2, p 323r«329, March^April,
1977. 1 fig, 2 tab, 48 ref, 19 equ.
Descriptors: Sodium, Cation exchange, Calcium, Magnesium, Cations, Soil chemistry,
Soil investigations, Soil properties, Computer programs, Soil tests.
68
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The theoretical chemical basis of the sodium adsorption ratio CSAR) was examined
in order to clarify two important issues that arise in connection with the problem
of estimating potential sodium hazard: (i) the relation between SAR and the theory
of cation exchange, and (ii) the implications of the universal practice of re^-
placing SAR by what may be termed the practical SAR, which employs total concern,
trations of Na, Ca, and Mg instead of their free cationic concentrations. In regard
to (i), it was confirmed that SAR can be given a chemical basis in terms of the
Gapon cation exchange equilibrium constant which is provided in this paper with
a rigorous derivation for the first time. The Gapon constant is shown to differ
from the Vanselow exchange constant only because of the (arbitrary) convention
adopted as to what entity is termed the ligand in the cation exchange reaction.
In regard to (ii), it was shown through a direct calculation of SAR and the
practical SAR for 161 different soil solutions or water extracts, utilizing
a comprehensive chemical equilibrium computer program, that an exact functional
relationship between the two parameters does not exist.
77:02G-138
EXCHANGE CAPACITY OF CALCIUM AND SODIUM SOILS AS DETERMINED BY DIFFERENT
REPLACING CATIONS,
Ravina, I., and Gurovich, E.
Technion-Israel Institute of Technology, Faculty of Agricultural Engineering,
Haifa, Israel.
Soil Science Society of America Journal, Vol. 41, No. 2, p 319-322, March-April,
1977. 2 fig, 5 tab, 26 ref.
Descriptors: Cation exchange, Calcium, Sodium, Soils, Soil investigations, Cations,
Soil properties.
Experimentally determined CEC values are dependent on the nature of the initially
adsorbed cation and the replacing one. Cation exchange capacities of Na-saturated
and Ca-saturated soils were determined using monovalent and divalent cations. In
the exchange of initially adsorbed Na or Ca by monovalent cations, the magnitude
of CEC increases with increasing ionic radius or polarizability of the replacing
cation. The Na soil shows a greater CEC than the Ca soils. The Na soil and Ca
soil behave -differently with respect to the exchange by divalent cations. While
the CEC of a soil initially saturated with Ca increases as the ionic radius of
the replacing cation is larger, the magnitude of CEC of a Na soil decreases.
77:02G-1Q9
PHOSPHORUS SORPTION CHARACTERISTICS OF FLOODED SOILS,
Khalid, -R.A., Patrick, W.H., Jr., and DeLuane, R.D.
Louisiana State University, Center for Wetland Resources, Baton Rouge, Louisiana.
Soil Science Society of America Journal, Vol. 41, No. 2, p 305^-310, Marchr-April,
1977- 4 fig, 3 tab, 29 ref.
Descriptors: Phosphorus, Soils, Soil investigations, Soil properties, Rice,
Crop production, Louisiana,
Surface soils representing Alfisols and Inceptisols were collected from various
parts of Louisiana under rice cultivation and incubated under oxidized (.aerobic)
and reduced (anaerobic) conditions for 2 weeks in a soil to 0.01M CaCl2 solution
ratio of 1:5. The release of native soil P and the sorption of added inorganic
P was investigated under these conditions. The soils selected for study were
characterized for clay content, total carbon, extractable P, pH, and oxalate-
extractable Fe, and soil properties associated with P sorption. The results
show that generally more soil P was released under reduced than oxidized con-
ditions, and this increase in soluble P under reduced conditions was signifi-
cantly related to Bray no. 2 extractable P, clay content, and oxalate Fe.
77:02G-110
MEASUREMENT OF ISOTOPIC EXCHANGEABLE SOIL PHOSPHORUS AND INTERRELATIONSHIP AMONG
PARAMETERS OF QUANTITY, INTENSITY, AND CAPACITY FACTORS,
Dalai, R.C., and Hallsworth, E.G.
New England University, Department of Agronomy and Soil Science, Armidale, New
South Wales 2351, Australia.
Soil Science Society of America Journal, Vol. 41, No, 1, p 81^86, January-
February, 1977. 6 tab, 28 ref, 10 equ.
69
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Descriptors: Phosphorus, Soils, Soil investigations, Soil chemistry, Soil tex-
ture, Soil chemical properties.
The applicability of various techniques to measure isotopically exchangeable
phosphorus for widely different soils was investigated. The E-values obtained
in the laboratory by carrier-free (E-value) and carrier-methods (Ec value) were
comparable to L-values obtained in the greenhouse in low-phosphorus fixing
soils but were very much higher in high phosphorus fixing soils. In the latter
group E-values obtained by inverse-dilution technique (E.I.D. value) were more
comparable to L-values.
77:02G-111
FITTING SOLUTE BREAKTHROUGH EQUATIONS TO DATA USING TWO ADJUSTABLE PARAMETERS,
Elprince, A.M., and Day, P.R.
King Faisal University, Department of Soils and Agricultural Engineering,
Al-Hassa, Saudi Arabia.
Soil Science Society of America Journal, Vol. 41, No. 1, p 39-41, January-
February, 1977. 2 fig, 1 tab, 20 ref.
Descriptors: Adsorption, Anions, Soils, Soil investigations, Hydrodynamics,
Soil chemistry, Soil chemical properties.
Negative adsorption of anions reduces the volume of liquid available for the
transport of electrolytes in the soil, and hence affects the nature of the break-
through curve. A similar problem arises when there are appreciable volumes of
soil solution which are essentially stagnant, and thus do not contribute signi-
ficantly to the convective flux. These effects can be taken into account by
introducing a second adjustable parameter (the effective solution volume) into
the transport equation, in addition to the dispersion coefficient. The calcu-
lations demonstrate in a given example that a least squares procedure, applied
simultaneously to the two parameters during the curve-fitting process, resolves
the apparent discrepancy between the theoretical breakthrough curve and the
experimental data.
77:02G-112
THERMODYNAMIC STABILITY AND SOLUBILITY OF MOLYBDENUM MINERALS IN SOILS,
Vlek, P.L.G., and Lindsay, W.L.
International Fertilizer Development Center, Florence, Alabama 35630.
Soil Science Society of America Journal, Vol. 41, No. 1, p 42-46, January-
February, 1977. 4 fig, 3 tab, 30 ref.
Descriptors: Molybdenum, Thermodynamics, Soil chemistry, Soil chemical pro-
perties, Soils, Soil investigations, Laboratory tests.
The chemical reactions of molybdenum in soils were studied in the laboratory.
Solubility diagrams were constructed from thermodynamic data obtained from the
literature and from measurements made on pure minerals. Included in these
diagrams were solubility relationships for molybdenite, ilsemannite, ferrimolybdite,
powellite, and wulfenite. From these diagrams it appears that wulfenite is one
of the most stable Mo minerals likely to form in soils. Lack of thermodynamic
data on other Mo minerals prevents their evaluation as possible reaction products.
The solubility of Mo in selected Colorado soils in the pH range of 5,5 to 7.7
was plotted on the wulfenite solubility diagram. Of the 13 soils used in this
study, only one showed equilibrium with respect to wulfenite. When wulfenite
was added to several other soils, the molybdenum solubility increased 10 to 100
fold, confirming that wulfenite was not initially present. These wulfenite^
amended soils showed a close correspondence between soluble Mo and the wulfenite
solubility isotherm. In the absence of solid phase Mo compounds, the solubility
of Mo in soils is controlled by specific adsorption,
77:02G-113
THE NITROGEN ISOTOPE EFFECT ASSOCIATED WITH NITRATE AND NITRITE LOSS FROM WATER-
LOGGED SOILS,
Chien, S.H., Shearer, G., and Kohl, D,H.
Washington University, Center for the Biology of Natural Systems, Saint Louis,
Missouri 63130.
Soil Science Society of America Journal, Vol. 41, No. 1, p 63-69, January-
February, 1977. 8 fig, 3 tab, 11 ref,
70
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Descriptors: Nitrogen, Isotopes, Nitrates, Nitrites, Saturated soils, Illinois,
Glucose, Denitrification, Soils, Soil investigations.
Changes in the isotopic composition of added N03(-), during the course of its
disappearance from two central Illinois soils are reported. The only known
difference in the two soils is the cultural history of the fields from which
they were taken. A large (approximately threefold) difference between the two
soils was observed in the isotopic fractionation factor associated with N03(->
loss. Large differences in the two soils with respect to both the rate of N03(-)
loss and the isotopic fractionation associated with it were apparently related
to differences in the two fields rather than to temporal or spatial variation
within the fields. Addition of glucose (1% with respect to dry soil weight)
caused the difference between the two soils to disappear. It also appreciably
reduced the apparent isotopic fractionation factor in both soils,
77:02G-114
EVALUATION OF SOIL NITROGEN MINERALIZATION POTENTIALS UNDER MODIFIED FIELD
CONDITIONS,
Smith, S.J., Young, L.B., and Miller, G.E.
United States Agricultural Water Quality Management Laboratory, Durant, Oklahoma
74701.
Soil Science Society of America Journal, Vol. 41, No, 1, p 74-76, Januarys-February,
1977. 1 fig, 3 tab, 11 ref,
Descriptors: Nitrogen, Soils, Soil investigations, Mineralization, Oklahoma,
Soil temperature, Soil water, Soil moisture.
Amounts of mineral N obtained by a calculation procedure and measurement in fallow
plots were compared during two cropping seasons and annually with eight Oklahoma
soils. The calculation procedure involved adjusting the N mineralization poten-
tials for varying soil temperature and water content. The field N measurements
involved the use of soil in plastic bags and glass filter tubes. Cropping season
and annual field amounts for the eight soils, on the average, ranged from 54 to
78 ppm N. In general, the calculated amounts compared favorably to the field
amounts, differences frequently being <10 ppm N. Calculated amounts correlated
as well or better with the field amounts than a variety of other N availability
indexes.
77:02G-115
FACTORS AFFECTING WATER DISTRIBUTION AFTER UNIFORM IRRIGATION,
Sinai, G., and Zaslavsky, D.
Technion, Department of Agricultural Engineering, Haifa, Israel,
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-29.
12 fig, 19 ref.
Descriptors: Irrigation, Irrigation water, Soil moisture, Soil water, Soil water
movement, Hydraulic conductivity, Irrigation effects.
Uniformly distributed irrigation water could infiltrate laterally so that the
spatial variability in moisture in the root zone would be very high. This was
observed in field experiments and was proved theoretically. A suggested explana-
tion was lateral flow in the soil due to anisotropy in its conductivity. Most
cultivated layers are anisotropic so lateral flow could occur in fields.
77:02G-116
EFFECT OF DRAIN DIAMETER, OPENINGS AND ENVELOPES ON WATER TABLE DRAWDOWN,
Skaggs, R.W., and Tang, Y.K.
North Carolina State University, Department of Biological and Agricultural
Engineering, Raleigh, North Carolina 27607.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-21.
10 fig, 4 tab, 15 ref.
Descriptors: Drainage, Drainage effects, Drainage engineering, Drainage
practices, Drainage systems, Soil water movement.
71
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Numerical solutions to the Richards equation for flow to parallel drains were used
to determine the effects of drain tube diameter, openings and envelopes on water
table drawdown.
77:02G-117
BENEFITS OF SURFACE DRAINAGE,
Estes, R.D., and Harris, W.S.
Arkansas Cooperative Extension Service, Division of Agricultural Engineering,
Little Rock, Arkansas.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-3.
3 tab, 3 ref.
Descriptors: Drainage, Drainage effects, Economics, Surface drainage.
Land was graded in approximately 40 ha. fields with a 40 ha. field left ungraded
as a check. Records of operating costs and yields were kept for a three-year
period. There was no appreciable difference in operating costs or yields. The
difference was in management benefits.
77:02G-118
PROCEDURES FOR EVALUATION OF DRAINAGE BENEFITS FOR AGRICULTURAL CROPS,
Manley, D.W.
United States Department of Agriculture, Soil Conservation Service, Midwest Tech-
nical Service Center, Lincoln, Nebraska,
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-6.
6 tab.
Descriptors: Economics, Drainage, Agriculture, Crop production, Drainage
practices, Drainage systems.
The basic concepts and procedures used by the Soil Conservation Service for making
an economic analysis of drainage for agricultural crops is described,
77:02G-119
RELATIONSHIPS BETWEEN SOIL UREASE ACTIVITY AND OTHER SOIL PROPERTIES,
Zantua, M.I., Dumenil, L.C., and Bremner, J.M,
Iowa State University, Department of Agronomy, Ames, Iowa 50011.
Soil Science Society of America Journal, Vol. 41, No. 2, p 350-352, March-April,
1977. 3 tab, 14 ref, 2 equ.
Descriptors: Iowa, Soils, Soil investigations, Soil properties, Cation exchange,
Soil texture, Organic matter.
Surface samples of 21 diverse Iowa soils representing a wide range in pH, texture,
and organic matter content were studied to determine the relationships between
soil urease activity and other soil properties. Simple correlation analyses show-
ed that urease activity was correlated very highly significantly with organic C
(r=0.72 at the 0.1% level), total N (r=0.71 at the 0,1% level), and cation-exchange
capacity (r=0.67 at the 0.1% level). Urease activity also was significantly cor-
related with clay (0.53 at the 5% level), sand (-0.47 at the 5% level), and surface
area (0.45 at the 5% level), but was not significantly correlated with pH, silt,
or CaC03 equivalent. Multiple regression analyses showed that organic matter con-
tent accounted for most of the variation in urease activity,
77:02G-120
PROFILE ACCUMULATION OF FERTILIZER-DERIVED NITRATE AND TOTAL NITROGEN RECOVERY IN
TWO LONG-TERM NITROGEN-RATE EXPERIMENTS WITH CORN,
Jolley, V.D., and Pierre, W.H.
Agricultural Home Economics Experiment Station, Ames, Iowa 50011,
Soil Science Society of America Journal, Vol. 41, No. 2, p 373-378, March-April,
1977. 1 fig, 5 tab, 26 ref.
72
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Descriptors: Fertilizers, Fertilization, Nitrates, Nitrogen, Corn, Crop response,
Soils, Soil investigations, Soil profiles, Denitrification.
Two long-term N-rate experiments with corn which had been conducted in northwestern
Iowa on the Moody and Galva silty clay loam soils for 17 and 15 years, respectively,
were studied to determine the recovery of applied N (i) as N03(-)N at various soil
depths, (ii) as organic or fixed N, and (iii) as N removed in the harvested corn
grain. The annual N rates applied as NH4N03 were 0, 56, 112, and 168 kg N/ha on
the Moody soil and 0, 90, and 134 kg N/ha on the Galva soil. Nitrogen recovery
in the fertilized plots was determined by subtracting the amounts for the unferti-
lized treatment from those for the fertilized treatments.
77:02G-121
ION EXCHANGE REACTIONS IN NONDRIED CHAMBERS MONTMORILLONITE HYDROXY-ALUMINUM
COMPLEXES,
Keren, R., Gast, R.G., and Barnhisel, R,I.
Minnesota University, Department of Soil Science, Saint Paul, Minnesota 55108.
Soil Science Society of America Journal, Vol. 41, No. 1, p 34-39, January-February,
1977. 1 fig, 3 tab, 30 ref.
Descriptors: Soils, Soil chemistry, Soil properties, Soil investigations, Mont-
morillonite, Clays, Sodium, Adsorption, Cation exchange.
The extent and mechanisms by which hydroxy-Al interlayer's may reduce the CEC of
Chambers montmorillonite were studied using 22-Na labeled clay. Clay-hydroxy-Al
complexes were formed by added A1C13 and NaOH at pH 7, 5-9, 5. A1C13 was added
at 4, 8, or 16 meq/g clay and either before, after, or simultaneously with NaOH.
Addition of 16 meq AlC13/g clay followed by NaOH resulted in CEC reductions of
60, 40, and 10% at pH 7.5, 8.5, and 9.5 as measured by Na adsorption. However,
there was no trapped or nonexchangeable 22-Na observed in any of the systems.
Since the charge on the hydroxy-Al is negligible at these pH''s, the CEC reduction
is apparently due to trapped Al.
77:02G-122
DRAINAGE LAW ASSISTS LAND DRAINAGE,
Irwin, R.W., and Johnston, J.R.
Guelph University, Department of Engineering, Guelph, Ontario, Canada.
American Society of Agricultural Engineers, Post Office Box 410, Saint Joseph,
Michigan 49085, Paper Number 77-2560. 59 fig.
Descriptors: Laws, Drainage, Drainage systems, Drains, Drainage practices.
Drainage law in Ontario is integrated to provide systems of procedures, financing
and inspections to ensure that agricultural drainage proceeds in a deliberate
and fair way. The law covers the construction of outlet drains, on-farm tile
drains and the regulation of the drainage construction industry.
77:02G-123
MODELING INFILTRATION UNDER MOVING SPRINKLER IRRIGATION SYSTEMS,
Slack, D.C.
Minnesota University, Department of Agricultural Engineering, Saint Paul, Minnesota.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-23.
9 fig, 1 tab, 21 ref, 10 equ.
Descriptors: Model studies, Infiltration, Sprinkler irrigation, Irrigation,
Irrigation systems, Soils, Simulation analysis,
A modified Mein and Larson model was employed to predict time to surface ponding
under two types of center pivot irrigation systems on two agricultural soils.
Results were compared with those observed in the field. The model did a good
job of predicting time to surface ponding but did not perform as well as for
predicting volume infiltrated at ponding.
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77:02G-l24
NONLINEAR ADSORPTION IN LAYERED POROUS MEDIA FLOW,
Lin, S.H.
Polytechnic Institute of New York, Department of Chemical Engineering, Brooklyn,
New York.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY9, Proceedings Paper 13192, p 951-958, September 1977. 3 fig, 11 ref,
2 append.
Descriptors: *Adsorption, *Dispersion, *Porous media, *Model studies. Mathematical
models, Seepage, Seepage control, Equations, Soil water, Soil water movement,
Solutes, Groundwater.
Dispersion and adsorption of solute in multilayer saturated porous media with con-
stant specific discharge were examined. Differential equations were formulated for
describing the solute concentration in two-layer porous media. A general nonlinear
equilibrium adsorption isotherm of the Freundlich type was considered. The non-
linear coupled differential equations were solved by the orthogonal collocation
method to give the solute concentration distributions in the media when subject
to a step-change or an exponential input. It was found that under many circum-
stances, the general dispersion model can be reduced to a simpler plug-flow
model by neglecting the dispersion component in the governing differential equa-
tions. A criterion for this simplification also was suggested.
77:02G-l25
TRANSIENT DRAINAGE EQUATIONS FOR NONHOMOGENEOUS SOILS,
Chu, S.T.
South Dakota State University, Department of Agricultural Engineering, Brookings,
South Dakota.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 6,
p 1085-1088, November-December, 1977. 3 fig, 3 tab, 9 ref.
Descriptors: *Drainage, *Soils, *Unsteady flow, *South Dakota, Water table,
Theoretical analysis, Model studies, Mathematical models, Analytical techniques,
On-site tests, Water levels, Hydraulic conductivity, Equations, Soil physical
properties, Nonhomogeneous soils, Drain spacing.
One of the limitations inherent in the derivation of many transient drainage
equations is the assumption of a homogeneous soil. Graphical representation of
transient drainage equation for nonhomogeneous soil was obtained by a scheme
devised by Bouwer. He devised a scheme where the soil profile is split up into
a number of_layers. Within each layer, the soil parameters were considered as con-
stants. He combined the solutions for each layer and obtained the solution of
the Green and Ampt infiltration equation for nonhomogeneous soils. The applica-
tion of the theoretical solution to predict the fall of a water table was illustra-
ed. An evaluation of the theory by field measurements was presented. Good agree-
ment between the theoretical and field measured water table height was found.
77:02G-126
VERTICAL DRAINAGE IN FIELD CORES,
Wells, L.G., and Skaggs, R.W,
Kentucky University, Department of Agricultural Engineering, Lexington, Kentucky,
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 1,
p 79-84, January-February, 1977. 7 fig, 2 tab, 15 ref.
Descriptors: *Drainage, *Cores, *Laboratory tests, Soil water movement, Soil
tests, Mathematical models, Hydraulic conductivity, Soil types, Pressure head,
Water table, Irrigation.
In this study, one-dimensional water movement during drainage was examined experi-
mentally using large field cores. The cores were 51 cm in diameter and were con-
sidered large enough to incorporate heterogenities such as worm holes and plant
roots, yet small enough to bring into the lab where experimental measurements
could be made under controlled conditions. The objective of the study was to
evaluate alternate methods of characterizing one-dimensional drainage in natural
soils with relatively shallow water tables.
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77:020-127
OPTIMAL PREDICTION OP PONDING,
Smith, R.E., and Parlange, J.Y.
Agricultural Research Service, Fort Collins, Colorado.
Transactions of the American Society of Agricultural Engineers, Vol. 20 No 3
p 493-496, May-June, 1977. 1 tab, 6 ref, 1 append.
Descriptors: *Ponding, *Runoff, *Rainfall, *Model studies, Mathematical models.
Soil physics. Porous media, Infiltration, Precipitation (atmospheric), Hydraulic
conductivity. Moisture content, Saturated soils, Surface runoff, Soil science,
Watersheds (basins).
Soil physics and porous media flow are being used more and more today to develop
means to predict hydrologic response of watersheds and to provide better manage-
ment tools for water resources. One important variable in studying watershed
response to storm rainfall is the time between initiation of rainfall and the in-
iation of surface runoff, or ponding time. This study described a mathematical
technique that allows improved estimates of the delay in watershed response to
rain, knowing only two basic soil parameters from the physics of soil water flow.
77:02G-128
SOIL WATER MODELING II: ON SENSITIVITY TO FINITE DIFFERENCE GRID SPACING,
Amerman, C.R., and Monke, E.J.
Agricultural Research Service, Columbia, Missouri.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 3,
p 478-484, 488, May-June, 1977. 10 fig, 2 tab, 18 ref.
Descriptors: *Soil water, *Soil water movement, *Model studies, *Mathematical
models, Infiltration, Finite element analysis, Analytical techniques, Mathe-
matics, Water levels, Flow, Hydraulic conductivity, Saturated flow, Unsaturated
flow, Hydrology.
The influence of finite difference grid size on soil water flow model accuracy
was studied using two cases. One case was of steady, two-dimensional infiltra-
tion using the successive overrelaxation (SOR) method of solving finite difference
equations. The other case was of transient, two-dimensional infiltration using
the alternating direction implicit (ADI) method. Finite difference expressions
were formulated for both cases using central differencing techniques, In the
transient case, a very small grid size in both time and space dimensions was
necessary at the initiation of infiltration. Furthermore, the ADI method for
the nonlinear case was only conditionally stable at least at the initiation of
infiltration. As infiltration proceeded, however, both the time and the space
grid sizes could be made larger. Indicators of a grid size that was obviously
too coarse were a fluctuating infiltration rate in the transient case and ir-
regulary shaped equipotential lines in the steady-state case. Although the
models were nonlinear, they both converged; for example, successively smaller
grid sizes yielded solutions that asymptotically approached a limit. For a
given regular grid size, considerable computational saving could be effected
without appreciable loss of accuracy by using an irregular grid in which the
regular grid size was duplicated in the part of the section exhibiting the
greatest curvature of equipotential lines, while larger grid sizes could be used
in other parts of the section. Smaller grid sizes also were needed in regions
where hydraulic gradient changed rapidly. Accuracy of estimation varied ap-
proximately with the inverse of grid size rather than with the square of the in-
verse, as is generally claimed for central differencing on a square grid.
77:026-129
A CONTINUOUS WATER BUDGET MODEL FOR WESTERN KANSAS,
Neibling, W.H., Koelliker, J.K., and Ohmes, F.E.
United States Department of Agriculture, Agricultural Research Service, Agricul-
tural Engineering Building, Purdue University, West Lafayette, Indiana.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-17. 5 fig, 3 tab, 22 ref, 4 equ.
Descriptors: Kansas, Model studies, Evapotranspiration, Soil moisture, Soil
water, Soil profiles, Climate.
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A continuous water-budget model was developed and calibrated for use in western
Kansas. Daily potential evapotranspiration (PET), actual ET, and soil moisture
changes in a 213 cm soil profile were calculated from inputs of crop and soil
moisture characteristics and daily meteorological observations.
77:02G-130
ADSORPTION OF ALUMINUM BY A SMECTITE: I. SURFACE HYDROLYSIS DURING CA2(+)(-)
AL3(+) EXCHANGE,
Bloom, P.R., McBride, M.B., and Chadbourne, B.
Cornell University, Department of Agronomy, Ithaca, New York 14853.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1068-1072, November-
December, 1977. 1 fig, 6 tab, 16 ref, 5 equ.
Descriptors: Adsorption, Aluminum, Montmorillonite, Clays, Soils, Soil chemistry,
Soil properties.
The exchange of Ca by Al in montmorillonite suspensions adjusted to low pH (approx-
imately equal to 4) was investigated by measurement of Ca, Al, and pH in the so-
lution phase before and after the addition of clay- Adsorption of Al was ac-
companied by a release of protons to solution, indicating that the clay surfaces
promoted hydrolysis of A13+ when only partial coverage of exchange sites by Al
had occurred. Calculations showed a two- to nine fold increase in the degree
of hydrolysis at the surface relative to the value for solution.
77:02G-l31
ADSORPTION OF ALUMINUM BY A SMECTITE: II. AN AL3( + ) (-)CA2( + ) ,
McBride, M.B., and Bloom, P.R.
Cornell University, Department of Agronomy, Ithaca, New York 14853,
Soil Science Society of America Journal, Vol. 41, No, 6, p 1073-1077, November-
December, 1977. 3 fig, 2 tab, 11 ref, 9 equ.
Descriptors: Model studies, Aluminum, Montmorillonite, Clays, Soils, Soil
chemistry. Soil properties.
The adsorption of Al by Ca2+-montmorillonite has been found to be described by
a Langmuir-type equation in which the activity of A13+ in solution is a function
of the coverage of the mineral surfaces by Al, The classical mass-action
equations were inadequate in describing the exchange reaction where the Ca2+
activity was allowed to vary, weighting the effect of the Ca2+ ion activity on
the equilibrium too heavily. The model suggests that the relative solution-like
nature of adsorbed Ca2+ compared to the much more strongly adsorbed A13+. Hy-
drolysis and precipitation reactions of A13+ at higher pH complicated the ex-
change model by introducing significant quantities of adsorbed hydroxyl-Al into
the system.
77:02G-132
PHOSPHATE ADSORPTION ON AN OXISOL,
Parfitt, R.L.
Soil Bureau, Division of Scientific and Industrial Research, Lower Hutt, New
Zealand.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1064-1067, November-
December, 1977. 1 fig, 1 tab, 22 ref.
Descriptors: Adsorption, Phosphates, Soil chemistry, Soil properties.
Adsorption isotherms f or _phos_phate on the A and B horizon of an oxisol from Papua
New Guinea showed high affinity adsorption at low solution concentrations and a
linear increase in adsorption at higher solution concentrations, Adsorption
increased with decrease in pH in the range 3 to 8. Comparison with data obtained
under similar conditions with synthetic goethite (alpha-FeOOH) and gibbsite
(A1(OH}3) suggested that phosphate reacted with FeOH and FeOH2+ groups on soil
iron oxide surfaces to form a binuclear bridging FeOP(.02)OFe complex and with
exposed A1(OH)H20 on kaolinite edges and on hydroxy-aluminum species to form a
binuclear or bidentate phosphate complex. At higher phosphate concentrations
isotherms showed continued adsorption which may be due to a further reaction
involving hydroxy-aluminum groups.
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77:02G-133
APPLICATIONS AND MISAPPLICATIONS OF THE LANGMUIR EQUATION TO SOIL ADSORPTION
PHENOMENA,
Barter, R.D., and Baker, D.E.
New Hampshire University, Institute of Natural and Environmental Resources,
Durham, New Hampshire 03824.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1077-1080 November-
December, 1977. 2 fig, 2 tab, 12 ref, 10 equ.
Descriptors: Adsorption, Soils, Soil investigations, Soil properties, Soil
chemistry.
When the development of the Langmuir adsorption equation is critically examined,
it is evident that the equation soil scientists have been using (C/x/m = C/k +
1/kb, where C is concentration of adsorbate, x/m is the amount adsorbed per unit
weight adsorbent, k is the adsorption maximum, and b is a constant) is in the
wrong form. This error is of no great importance when the equation is merely
used to obtain a calculated adsorption maximum for comparison to other adsorbent
properties. However, it does become important when attempts are made to under-
stand adsorption dynamics and bonding strengths. The commonly reported curvi-
linear nature of the C/x/m vs. C plots is simply the result of not considering
the effect of desorbed ions in the equilibrium solution, rather than being due
to multiple adsorption mechanisms. When the equation is corrected by consider-
ing desorbed ions, the isotherm becomes linear. In addition, the constant,
b, of the Langmuir equation is not simply related to the bonding energy of the
adsorbed ion, but to the ratio of adsorbed and desorbed ion bonding energies.
77:020-134
AMMONIA VOLATILIZATION PROM SOILS: EQUILIBRIUM CONSIDERATIONS,
Avnimelech, Y., and Laher, M.
Israel Institute of Technology, Department of Agricultural Engineering, Technion
City.- Haifa, Israel.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1080-1084, November**
December, 1977. 2 fig, 1 tab, 9 ref, 18 equ.
Descriptors: Ammonium, Soils, Soil chemistry, Soil properties, Fertilizers,
Nutrients.
The volatilization of ammonia from soils as a function of the system's properties
is analyzed theoretically and experimentally. The final concentration of am-
monium held by the soil increases with an increase in hydrogen ion activity, with
the initial ammonium concentration, and with partial pressure of ammonia in the
air. An increase in the buffer capacity of the soil leads to a decrease in the
final ammonium concentration. A good agreement has been found between measured
and computed values for NH3 and NH4 concentrations during the process. The pH
of the soil is the dominant factor controlling the extent of ammonia volatili-
zation only when the soil's buffer capacity is high, or, when the concentration
of ammonium in the soil is low. At high pH and high initial ammonium concen-
trations, the dominant factor controlling the reaction is the buffer capacity
of the soil.
77:02G-135
ORGANIC PHOSPHATE TRANSPORT AND HYDROLYSIS IN SOIL: THEORETICAL AND EXPERIMENTAL
EVALUATION,
Castro, C.L., and Rolston, D.E.
California University, Department of Land, Air, and Water Resources, Davis,
California 95616.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1085-1091, November-
December, 1977. 7 fig, 1 tab, 28 ref, 7 equ.
Descriptors: Phosphates, Soils, Soil chemistry, Fertilizers, Irrigation,
Irrigation water.
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An understanding of the movement, hydrolysis, and retention of organic phosphates
in soils is necessary to evaluate possible advantages of the compounds as ferti-
lizers, based upon their characteristic of increased vertical movement over that
of inorganic phosphates when applied with irrigation water. Pulses of chloride
and glycerophosphate were applied to 4-, 10-, and 20-cm long Panoche clay loam
soil columns maintained slightly water-unsaturated. The concentration of gly-
cerophosphate in the pulse applications varied from 386 to 1,110 ppm P. An
analytical solution assuming first order kinetics and a reversible, linear iso-
therm for glycerophosphate hydrolysis and sorption, respectively, was compared
with measured glycerophosphate concentrations in the column effluent. An analy-
tical solution of the coupled equations for simultaneous transport of organic
phosphate and orthophosphate assuming a linear, reversible isotherm for ortho-
phosphate adsorption is given.
77:02G-136
TRAFFIC COMPACTION AND IRRIGATION,
Trouse, A.C., Jr.
United States Department of Agriculture, Agricultural Research Service, National
Tillage Machinery Laboratory, Auburn Alabama.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 50-53, February 13, 15, 1977. 1 tab.
Descriptors: Irrigation, Irrigation practices, Irrigation effects, Soils, Soil
compaction, Soil moisture, Soil water, Crop production.
When traffic compaction is present, no amount of irrigation will guarantee super-
ior crop yields. Neither will well irrigated fields guarantee top production
when soils are only mildly compressed, a common, but less organized, situation
on many farms today. If moisture is to increase crop production, it must be
both available and readily retrievable when needed, by whatever its method of
entry into the soil.
77:02G-137
FINITE ELEMENT MODELING OF UNSATURATED FLOW,
Bloomsburg, G.L., and Bloomfield, R.A.
Idaho University, Department of Agricultural Engineering, Moscow, Idaho,
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-21,
7 fig, 3 tab, 5 ref.
Descriptors: Simulation analysis, Unsaturated flow, Mining, Infiltration, Rain-
fall, Evaporation, Model studies, Soil water movement, Soil water.
This report concerns the use of a finite element computer program to simulate
unsaturated flow through retorted oil shale piles under various conditions of
ponding, infiltration due to rainfall, and evaporation. Field data from see-
page ponds constructed in waste shale near Rifle, Colorado, are compared with
data from computer simulation.
77:02G-138
APPLICATION OF AN INFILTROMETER SYSTEM FOR DESCRIBING INFILTRATION INTO SOILS,
Brakensiek, D.L., Rawls, W.J., and Hamon, W.R,
United States Department of Agriculture, Agricultural Research Service, Boise,
Idaho.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-14,
7 fig, 4 tab, 24 ref, 3 equ.
Descriptors: Infiltration, Soil water, Soil water movement, Model studies,
Equations.
The design and operation of an infiltrometer system is discussed. The analysis
of the infiltrometer data is illustrated by estimation of the parameters in the
Green and Ampt infiltration equation. The Green and Ampt equation seems to
model the observed point infiltration process very well. Future needs in in-
filtrometer studies are presented.
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77:02G-139
INFILTRATION EQUATION: DERIVATION TO INCLUDE SURFACE EFFECTS
Gregory, J.M., Johnson, H.P., and Kirkham, D.
Missouri University, Department of Agricultural Engineering, Columbia, Missouri.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-31,
4 fig, 2 tab, 15 ref, 76 equ.
Descriptors: Infiltration, Equations, Model studies, Soil water. Soil water
movement.
An infiltration equation capable of modeling changing surface conditions has been
derived by use of the energy equation. This equation has the surface effects
grouped in one function which can be separated from other variables affecting
infiltration. When the surface term is set equal to zero, the equation reduces
to the same form as the Green-Ampt equation.
77:02G-140
WATER MOVEMENT AND INFILTRATION IN A FROZEN SOIL: THEORETICAL AND EXPERIMENTAL
CONSIDERATIONS,
Steenhuis, T.S., Bubenzer, G.D., and Walter, M.F.
Cornell University, Department of Agricultural Engineering, Ithaca, New York
14853.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-31.
8 fig, 2 tab, 20 ref, 13 equ. 2 append.
Descriptors: Soil water, Soil water movement. Infiltration, Soils, Soil proper-
ties, Temperature, Soil temperature.
Water movement in a frozen soil was compared theoretically and experimentally
with a nonfrozen soil. During the winter, water movement was upwards to the
surface. Infiltration of water was only possible when the soil temperature was
at freezing point, but not below, or when the soil contained macropores.
77:02G-141
CAPILLARY POTENTIAL DISTRIBUTIONS IN ROOT ZONES USING SUBSURFACE IRRIGATION,
Thomas, A.W., Duke, H.R., and Kruse, E.G.
United States Department of Agriculture, Watkinsville, Georgia,
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 62-67, February 20, 1977. 11 fig, 8 ref,
Descriptors: Infiltration, Root zones, Subsurface irrigation, Corn, Irrigation
systems, Soils, Irrigation design, Capillary water.
An experimental study was conducted to study infiltration from buried sources
which represented field irrigation laterals. Capillary potentials in the root
zone of barley and corn were measured during the growing season and compared
with measured and calculated steady-state values. Design evaluation of sub-
surface irrigation system was introduced and example calculations were presented,
77:02G-142
THE SOIL MOISTURE COMPONENT OF MATHEMATICAL CATCHMENT SIMULATION MODELS,
Manley, R.E.
Seven-Trent Water Authority, Birmingham (England),
Journal of Hydrology, Vol. 35, No. 3/4, p 341-356, November 1977. 5 fig, 4 tab,
19 ref.
Descriptors: *Watersheds (basins), *Runoff, *Model s.tudies, Flow, Mathematical
models. Soil moisture, Infiltration, Permeability, Overland flow, Precipitation
(atmospheric), Rainfall, Soil water movement, Percolation, Evapotranspiration,
Groundwater, Channel flow, Hydrology.
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The role of soil moisture in mathematical catchment simulation models was dis-
cussed, and requirements for this component of the model were suggested. A
model was described which embodies the suggested characteristics, particular
emphasis being placed on its soil moisture component. The results from the ap-
plication of this model were presented.
77:02G-l43
NONLINEAR ADSORPTION IN POROUS MEDIA WITH VARIABLE POROSITY,
Lin, S.H.
Melbourne University, Department of Chemical Engineering, Parkville (Australia) .
Journal of Hydrology, Vol. 35, No. 3/4, p 235-243, November 1977. 6 fig, 17 ref.
Descriptors: *Porous media, *Adsorption, *Dispersion, *Model studies, *Porosity,
Mathematical models, Solutes, Seepage, Soil water, Soil water movement, Nutrients,
Nutrient removal, Nitrogen, Phosphorus, Liquid wastes, Path of pollutants, Soil
properties.
A numerical procedure was presented for predicting the solute dispersion and ad-
sorption in heterogeneous porous media. Several porosity equations with decreasing
or increasing porosity were proposed to represent the porosity variation and were
used to simulate how the porosity variation affects the solute concentration dis-
tribution. The solute responses subject to a step change or an exponential change
input revealed some interesting characteristics.
77:020-144
ALFALFA PRODUCTION ON A PROFILE-MODIFIED SLOWLY PERMEABLE SOIL,
Eck, H.V., Martinez, T., and Wilson, G.C.
United States Department of Agriculture, Southwestern Great Plains Research Center,
Bushland, Texas 79012.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1181-1186, November-
December, 1977. 2 fig, 6 tab, 8 ref.
Descriptors: Irrigation, Irrigation effects, Alfalfa, Crop production, Crop
response, Soils, Soil investigations.
Yields of irrigated alfalfa are lower on Pullman clay loam than on more permeable
soils in the same climatic area. The objectives of this study were to determine
(i) the residual effect of thoroughly mixing the soil profile on alfalfa growth
and production, and (ii) the amounts and timing of irrigations required for max-
imum alfalfa production on modified and unmodified soil profiles.
77:02G-145
POTASSIUM ACCUMULATION AND MOVEMENT IN AN IRRIGATED SOIL TREATED WITH ANIMAL
MANURES,
Pratt, P.P., and Laag, A.E.
California University, Department of Soil and Environmental Science, Riverside,
California.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1130-1132, November-
December, 1977. 3 fig, 3 tab, 9 ref.
Descriptors: Salinity, Potassium, Irrigation effects, Soils, Soil investigations,
Animal wastes, Soil chemistry.
Data from a 4-year experiment with animal manures are reported. Soluble and
exchangeable K and K/C1 ratios indicated that K moved into the 90- to 120-cm
depth, but little if any moved below the 120-cm depth, Potassium/Cl ratios in-
dicated that K moved down in a relatively abrupt front, that the 0- to 30-cm and
30- to 60-cm depths had nearly equilibrated with the K input, but that deeper
layers had not. Soluble K accumulated in the soil in proportion to the amount of
manure added and reached a maximum of 36.5% of the total soluble cations in the
saturation extract of the surface layer of the plots that received the highest
rate of manure. The maximum exchangeable K was found in the 30- to 60-cm depth
of the same plots. The K fixed in the soil appeared to be greater than the re-
duction in CEC.
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77:02G-146
DISTRIBUTION PATTERN OF INORGANIC NITROGEN FOLLOWING ANHYDROUS AMMONIA INJECTION
INTO A VERTISOL,
Khengre, S.T., and Savant, N.K.
Mahatma Phule Krishi Vidyapeeth Agricultural University, Department of Agricultural,
Chemical and Soil Science, Rahuri, India.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1139-1141 November-
December, 1977. 3 fig, 1 tab, 20 ref.
Descriptors: Nitrogen, Ammonia, Soils, Soil investigations, Soil chemistry, Soil
moisture, Soil water.
Distribution patterns of inorganic forms of N and diffusion coefficients of NH4 +
were studied after injection of 800 mg of anhydrous NH3-N per dish, each dish
containing 1 kg of soil (density 1,20 g/cu cm) maintained at 1/3-bar moisture
percentage and incubated for 120 days. Bell-shaped distribution patterns of NH4+
and undissociated NH3 (aq) were observed. Diffusion coefficients of NH4+ de-
creased with" incubation time.
77:02G-147
NITROGEN FERTILIZATION: II. EFFECT ON THE SOIL SOLUTION COMPOSITION, ACIDITY,
AND NITRATE ADSORPTION.
Lutz, J.A., Jr., Kroontje, W., and Hahne, H.C.H.
Virginia Polytechnic Institute and State University, Department of Agronomy,
Blacksburg, Virginia 24061.
Soil Science Society of America Journal, Vol. 41, No. 3, p 568-572, May-June,
1977. 3 tab, 31 ref.
Descriptors: Nitrogen, Nutrients, Fertilizers, Fertilization, Nitrates, Ad-
sorption, Soils, Soil investigations, Clays, Irrigation, Irrigation effects.
Analyses were performed on soil solution extracts of samples obtained from depths
where nitrate accumulation occurred due to ammonium nitrate applications on
three different soils, for example, Cecil fine sandy loam, Groseclose silt loam,
and Davidson clay loam. Comparisons were made between treatments of moderate
and high N applications in all three soils and between irrigated and nonirrigated
conditions on the Cecil and Davidson soils.
77:02G-148
NUMERICAL EVALUATION OF GRANULE SIZE EFFECT ON DISSOLUTION RATE OF POTASSIUM
SILICATES AND POTASSIUM POLYPHOSPHATE IN AQUEOUS SOLUTION,
Miwa, E., and Kurihara, K.
National Institute of Agricultural Sciences, 2-1-7 Nishigahara, Kita-ku, Tokyo,
114 Japan.
Soil Science Society of America Journal, Vol. 41, No. 3, p 637-640, May-June,
1977. 2 fig, 3 tab, 12 ref, 4 equ.
Soil properties,
Descriptors: Potassium, Kinetics, Soils, Soil investigations,
Soil chemistry, Soil water. Soil moisture.
The rate of potassium dissolution from spherical granules of K20-4S102, K20-5Si02,
and (Kp03)n was measured in water, NH4C1 and acetic acid solutions. Experimental
results were analyzed using first order kinetics, involving a rate constant (k)
and the concentration at saturation (cs). The kCs values in H20 were 3,65 x 10-2,
1.17 x 10-2, and 7.08 x 10-3 mg K/mm2 per day for K20-4S102, K205SiOs,_and (KP03)n,
respectively. Extremely high kCs values were obtained for the dissolution of
(KP03)n in solvents rich in H+ or NH4+. Based on these experimental aata and as-
sumed values for Cs, the whole process of K dissolution from each mineral_at var-
ious granule sizes in aqueous solutions was calculated by the equations given by
Hixson and Crowell (1931) .
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77:02G-l49
AN ALKALINE OXIDATION METHOD FOR DETERMINATION OF TOTAL PHOSPHORUS IN SOILS,
Dick, W.A., and Tabatabai, M.A.
Iowa State University, Department of Agronomy, Ames, Iowa 50011.
Soil Science Society of America Journal, Vol. 41, No. 3, p 511-514, May-June,
1977. 7 tab, 13 ref.
Descriptors: Phosphorus, Soils, Soil investigations, Nutrients, Fertilizers,
Fertilization, Sediments.
A simple and precise method for determination of total phosphorus in soils and
lake sediments is described. A mixture of soil and sodium hypobromite solution
is boiled to dryness in a sand bath (260-280 C), and the total amount of ortho-
phosphate is extracted with IN H2S04 and determined colorimetrically by the
molybdenum blue method. Analysis of a group of diverse soil, lake sediment,
and sewage sludge samples indicated that the proposed method and the HC104 di-
gestion method gave essentially the same total P values. With 10 soils, the
average results by the proposed NaOBr oxidation method were 1% higher than those
obtained by the HC104 digestion method and 4% lower than those obtained by the
Na2C03 fusion method. A comparison of methods used for colorimetric determina-
tion of the orthophosphate extracted indicated that the results by the recently
developed method by Dick and Tabatabai agree closely with those obtained by the
method of Murphy and Riley. Digestion of samples with sodium hypobromite solu-
tion and colorimetric determination of the extracted P by the method of Murphy
and Riley permits rapid analysis of a large number of samples at one time.
77:02G-l50
SHORT-TERM REPLENISHMENT OF SOIL SOLUTION PHOSPHORUS,
Peaslee, D.E., and Ballaux, J.C.
Kentucky Agricultural Experiment Station, Lexington, Kentucky 40506,
Soil Science Society of America Journal, Vol. 41, No. 3, p 529-531, May-June,
1977. 1 fig, 1 tab, 13 ref.
Descriptors: Phosphorus, Nutrients, Fertilization, Fertilizers, Soil properties,
Crop production, Soils, Soil chemistry.
Depletion of soil solution P from zones around plant roots indicates that diffusive
flux of P from the soil solution to the plant root is inadequate to keep pace with
removal by plant roots. Consequently, the concentration and/or concentration
gradients of solution P maintained under conditions of repeated removal over time
are an important soil property that is a factor in determining the quantity of P
diffusing to root surfaces. This study was conducted to determine the P release
characteristics of five soils differing in P retention properties and pretreated
with quantities of P equivalent to their sorption maxima.
77:02G-151
OBSERVED AND PREDICTED RATES OF PHOSPHORUS DIFFUSION IN SOILS OF VARYING BULK
DENSITY AND WATER CONTENT,
Hira, G.S., and Singh, N.T.
Punjab Agricultural University, Department of Soils, Ludhiana, India.
Soil Science Society of America Journal, Vol. 41, No. 3, p 537-540, May-June,
1977. 5 fig, 2 tab, 14 ref, 6 equ.
Descriptors: Phosphorus, Soils, Soil chemistry, Soil investigations. Soil water,
Soil moisture, Bulk density, Adsorption.
The self-diffusion coefficient of phosphorus (D) was measured at bulk densities
of 1.25, 1.45, 1.60 and 1.75 g/cm3 and at three levels of soil water content in
Choa sandy loam and Haibowal silty clay loam. The tortuosity factor was cal-
culated from the self-diffusion coefficient of 36C1. Appropriate values of the
adsorption isotherm and the tortuosity factor were used to predict P diffusion
coefficient in both soils. The tortuosity factor increased with increase in
soil bulk density and increase in water content from 7 to 18% in the Choa soil
and 14 to 25% in the Haibowal soil. As bulk density increased from 1.25 to 1.60
g/cm3, the observed diffusion coefficient values averaged over all water contents,
increased from 0.05 x 10(-10) cm sq/sec in Choa and Haibowal soils, respectively.
Further increase in bulk density to 1.75 g/cu cm decreased the diffusion coeffi-
cient of P in both soils to a greater extent than at low bulk density. The phos-
phate ion-soil particle interaction was minimum at a soil bulked density of 1.60
g/cu cm.
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77-.02G-152
AMMONIA VOLATILIZATION PROM SURFACE APPLICATIONS OF AMMONIUM COMPOUNDS TO CAL-
CAREOUS SOILS: VI. EFFECTS OF INITIAL SOIL WATER CONTENT AND QUANTITY OF
APPLIED WATER,
Fenn, L.B., and Escarzaga, R.
Texas Agricultural Experiment Station, Texas A and M Research Center at El Paso
1380 A and M Circle, El Paso, Texas 79927.
Soil Science Society of America Journal, Vol. 41, No. 2, p 358-363 March-April
1977. 5 fig, 1 tab, 12 ref.
Descriptors: Ammonia, Soils, Soil investigations, Irrigation, Irrigation effects,
Soil water, Soil moisture, Soil water movement.
Ammonia losses from (NH4)2S04(AS) and NH4N03(AN) applied to the surface of
initially wet and initially dry soils, when followed by irrigation, were generally
greater from the initially wet soils, especially when water application rates were
<2.5 cm. The greatest NH3 loss occurred at the lowest water addition and the
least loss at the highest water addition. The addition of 20.3 cm of water to a
Harkey silty clay loam did not reduce NH3 loss below that found with the addition
of 5.1 cm of water. Ammonium was moved deeper into the soil by water in the
initially wet soil than into the initially dry soil,
77:02G-153
ENVIRONMENTAL IMPLICATIONS OF TRENDS IN AGRICULTURE AND SILVICULTURE. VOLUME 1:
TREND IDENTIFICATION AND EVALUATION,
Unger, S.G.
Development Planning and Research Associates, Incorporated, Manhattan, Kansas
66502.
United States Department of Commerce, National Technical Information Service,
PB-274 233, October 1977. 188 p, 37 fig, 32 tab, 55 ref, 1 append.
Descriptors: Agriculture, Silviculture, Environmental effects. Environmental
quality management.
Current and emerging trends in United States agriculture and silviculture that
will have the most significant environmental implications in both the short term
(1985) and the long term (2010) are determined and assessed. Five major sub-
sectors of agriculture and silviculture were included in the analysis: (1) non-
irrigated crop production, (2) irrigated crop production, (3) feedlot production,
(4) range and pasture management, (5) silviculture and harvest management. Within
each subsector, numerous trends and developments were identified and defined by
the Contractor. Thereafter, an evaluation workshop, comprised of subsector
professionals from throughout the nation, evaluated, rated and rank-ordered the
most significant environmentally related trends.
77:02G-l54
SULFURIC ACID AS AN AMENDMENT FOR RECLAIMING SOILS HIGH IN BORON,
Prather, R.J.
United States Salinity Laboratory, Post Office Box 672, Riverside, California
92502.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1098-1101, November-
December, 1977. 1 fig, 3 tab, 29 ref.
Descriptors: Adsorption, Laboratory studies, Sulfuric acid, Boron, Leaching,
Soils, Soil profiles, Soil amendments.
Laboratory results indicated that sulfuric acid can effectively aid in reclaiming
soils high in boron. Results of a study, using 80-cm columns of a soil high in
B, indicated that a surface application of 3.22 metric tons/ha of concentrated
(96%) H2S04 followed by leaching with 3 pore volumes, p.v. of water was nearly
as effective in reducing the level of water-soluble soil B as was leaching with
16 p.v. of water. A direct pH effect on B adsorption affinity can explain the
enhanced reclamation effect found at lower soil column depths. Data suggested
that competition by silicate ion for adsorption sites may be contributing to
the enhanced desorption of B at lower soil depths.
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77:02G-155
STABILIZATION OF CALCIUM BY SURFACE CHARGE VARIATION IN AN OXISOL,
Munns, D.N., and Fox, R.L.
California University, Department of Soils and Plant Nutrition, Davis, California
95616.
Soil Science Society of America Journal, Vol. 41, No. 4, p 682-685, July-August,
1977. 3 fig, 24 ref.
Descriptors: Calcium, Soils, Soil investigations, Soil chemistry, Soil water,
Soil moisture, Cation exchange, Salts.
In the surface layer of a Ca-deficient, fine-textured Hawaiian Oxisol, concen-
trations of Ca in solution were poised against tendencies to increase with liming
in the pH-range 5-6, and to decrease with dilution in the range of water content
0.35 to 2.0. Effects of lime and water content on the distribution of Ca between
solid phase and solution were shown to be quantitatively consistent with effects
of pH and ionic strength on exchange capacity. Relationships between soil pH,
cation exchange capacity, and dissolved Ca were determined in soil samples taken
from a field-liming trial. Effects of ionic strength on exchange capacity were
determined by summation of adsorbed metal cations after equilibration of soil
samples in different salt solutions. Effects of water content on cations in
solution were determined by analysis of solutions centrifugally extracted at var-
ious water contents,
77:02G-156
SHORT COMMUNICATION: EFFECT OF SOIL MOISTURE ON THE RELEASE OF ORGANIC CARBON
FROM WHEAT ROOTS,
Martin, J.K.
Commonwealth Scientific and Industrial Research Organization, Division of Soils,
Glen Osmond, South Australia 5064.
Soil Biology and Biochemistry, Vol. 9, No. 4, p 303-304, 1977. 1 tab, 6 ref.
Descriptors: Soil water, Soil moisture, Carbon, Wheat, Root systems, Crop
response, Organic compounds.
A strong influence of soil moisture on the release of 14C-labelled organic material
into soil from cereal roots was shown by Barber and Martin (1976) , There was a
four-fold reduction of 14C-labelled water-soluble organic C in soil from pots
regularly leached with distilled water compared with soil from pots which had no
water addition, other than an initial wetting of the soil to 16% by weight with
nutrient solution. Leaching also affected the composition of the water-soluble
material. It was not possible to determine from these experiments the relation-
ship between the soil water content and C release from the roots. This paper pre-
sents results for the release of organic C from wheat roots grown at three dif-
ferent soil water contents.
77:02G-157
SOIL MICROBIAL AND BIOCHEMICAL CHARACTERISTICS IN RELATION TO SOIL MANAGEMENT
AND FERTILITY,
Verstraete, W., and Voets, J.P.
Gent University, Laboratory of General and Industrial Microbiology, Coupure
533, 9000 Gent, Belgium.
Soils Biology and Biochemistry, Vol. 9, No. 4, p 253-258, 1977. 5 tab, 18 ref.
Descriptors: Soil investigations, Fertilization, Nutrients, Fertilizers, Soil
properties, Soil chemistry, Crop response, Mineralization, Organic matter, Sugar-
beets.
From 1969 to 1974, two experimental fields were studied in terms of their soil
microbial and biochemical characteristics in relation to soil management practice
and crop yields. Of the various microbial and biochemical properties measured
soil phosphatase, saccharase, beta-glucosidase and urease activities, N mineraliza-
tion and soil respiration were found valuable to characterize the soils. These
characteristics increased with increasing soil organic matter, clay and CaC03
content. They also revealed a strong effect of organic fertilization. Multiple
regression analyses indicated that the alkalinity and the humus content of the
soil largely determined the magnitude of these characteristics. The regression
analyses also showed that the yields of winter wheat were related positively to
phosphatase activity while the sugarbeet yields x*ere related negatively to soil
urease activity.
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77:02G-153
SULFUR OXIDATION AND RESPIRATION IN 54-YEAR-OLD SOIL SAMPLES
Bollen, W.B. '
United States Department of Agriculture Forest Service, Pacific Northwest Forest
and Range Experiment Station, Forestry Sciences Laboratory, Corvallis, Oregon
Soil Biology and Biochemistry, Vol. 9, No. 6, p 405-410, 1977. 3 tab, 15 ref.
Descriptors: Sulfur, Respiration, Sampling, Oxidation, Soil chemistry, Soil
investigations, Soil properties, Soil tests, Soils.
Soil samples in dry storage for 54 years were shown to retain their ability to
respire and to oxidize S. Three of the soils had lower S-oxidizing capacity
and three oxidized more S at 1 g kg -1 than did the samples when originally
collected. When the experiment was repeated with all apparatus sterilized by
autoclaving and S sterilized in flowing steam, a greater proportion of the S
was oxidized. This was not due to heat treatment of the S, In all cases, S
additions and incubation resulted in a lowering of the soil pH, suggesting
that Thiobacillus thiooxidans was responsible and had survived the prolonged
storage. When the soils, before and after incubation, were added to Thiobacillus
media, only Gram-positive bacteria, mostly Bacillus spp., were found.
77:026-159
EFFECT OF NITROGEN DIOXIDE ON NITRITE OXIDATION AND NITRATE-OXIDIZING POPULA-
TIONS IN SOIL,
Ghiorse, W.C., and Alexander, M.
Cornell University, Department of Agronomy, Laboratory of Soil Microbiology,
Ithaca, New York 14853.
Soil.Biology and Biochemistry, Vol. 9, No. 5, p 353-355, 1977. 2 fig, 9 ref.
Descriptors: Nitrogen, Nitrites, Oxidation, Soils, Soil investigations.
When nitrogen dioxide was added to soil at a rate equivalent to 51 mu g N g -1
soil, the nitrite formed was oxidized logarithmically- The numbers of nitrite-
oxidizing microorganisms also increased logarithmically, but the final count
was too low to account for the amount of nitrite metabolized. In soil treated
with N02 at a rate equivalent to 106 mu g N g -1, the nitrite formed was oxidized,
but the counts of autotrophic nitrite Qxidizers did not rise. Discrepancies
between predicted bacterial numbers and nitrifying activity were also noted in
soils amended with nitrite.
77:02G-160
SALINITY AND NITROGEN MINERALIZATION IN SOIL,
Laura, R.D.
Indian Agricultural Research Institute, Division of Soil Science and Agricultural
Chemistry, New Delhi 110012.
Soil Biology and Biochemistry, Vol. 9, No. 5, p 333-336, 1977. 5 tab, 22 ref.
Descriptors: Salinity, Saline soils, Nitrogen, Mineralization, Nitrification,
Ammonification, Urea, Salts, Soil amendments.
The effects of salinity on ammonification have been reviewed. It is suggested
that ammonification could be due to the protolytic action of water and the in-
fluence of added salts on ammonification might be due to their effects on^the
degree of dissociation of water. The process of nitrification, however, is be-
lieved to be due to autotrophic organisms. Depending on the amounts applied to
soil, nitrification has been found to be retarded, suppressed or inhibited com-
pletely by salt addition. This experiment was made to re-examine the effects of
salinity on ammonification, nitrification and mineral N accumulation of native
soil N and N added in farm compost, mustard oil cake or urea. The experiment
was run over a long period.
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77 :02G-161
STUDIES OF NITROGEN IMMOBILIZATION AND MINERALIZATION IN CALCAREOUS SOILSI.
DISTRIBUTION OF IMMOBILIZED NITROGEN AMONGST SOIL FRACTIONS OF DIFFERENT PARTICLE
SIZE AND DENSITY,
Ladd, J.N., Parsons, J.W., and Amato, M.
Commonwealth Scientific and Industrial Research Organization, Division of Soils,
Glen Osmond, South Australia 5064.
Soil Biology and Biochemistry, Vol. 9, No. 5, p 309-318, 1977. 5 fig, 5 tab,
27 ref.
Descriptors: Nitrogen, Mineralization, Calcareous soils, Soils, Soil investiga-
tions, Soil texture, Soil density, Glucose, Wheat, Soil amendments, Soil mois-
ture, Soil chemistry.
Studies of the relative availability of nitrogenous components of soils have
mostly been chemically based. Of the chemically "defined" components, acid-
hydrolyzable amino acid-N appears to contribute most in inorganic-N is judged
by the amounts of N lost from this organic-N pool during periods of net mineral-
ization. However, measurements of the percentage decrease of N from soil chemical
fractions show that no'component is consistently of greater biological avail-
ability.
77:02G-162
STUDIES OF NITROGEN IMMOBILIZATION AND MINERALIZATION IN CALCAREOUS SOILSII.
MINERALIZATION OF IMMOBILIZED NITROGEN FROM SOIL FRACTIONS OF DIFFERENT PARTICLE
SIZE AND DENSITY,
Ladd, J.N., Parsons, J.W., and Amato, M.
Commonwealth Scientific and Industrial Research Organization, Division of Soils,
Glen Osmond, South Australia 5064.
Soil Biology and Biochemistry, Vol. 9, No. 5, p 319-325, 1977. 1 fig, 5 tab,
23 ref.
Descriptors: Nitrogen, Mineralization, Calcareous soils, Soils, Soil investi-
gations, Soil texture, soil density, Glucose, Wheat, Soil amendments, Soil mois-
ture. Soil chemistry.
15N03(-) was immobilized in a calcareous sandy soil and a calcareous clay soil
each incubated with glucose and wheat straw. Net mineralization of organic-15N
was more rapid in the sandy soil, irrespective of C amendment, and in soils amended
with glucose. Intermittent drying and wetting of soils during incubation stimu-
lated mineralization of 15N-labelled and native soil organic-N in all treatments.
The availability (percentage mineralization) of recently-immobilized 15N consis-
tently exceeded that of the native soil N. Ratios of the availability of label-
led and unlabelled N were similar in the sandy and clay soils but varied according
to C amendment, drying and wetting cycle and incubation period.
77:02G-163
EFFECT OF BIURET CONTENT ON TRANSFORMATION OF UREA NITROGEN IN SOIL,
Sahrawat, K.L.
Indian Agricultural Research Institute, Division of Agricultural Chemicals,
New Delhi 1100 12, India.
Soil Biology and Biochemistry, Vol. 9, No. 3, p 173-175, 1977. 2 tab, 16 ref.
Descriptors: Urea, Nitrogen, Nutrients, Fertilizers, Fertilization, Soil chemistry,
Nitrites.
The effect of the biuret content on transformations of urea-N was studied in a
sandy loam (pH 7.7). While biuret did not affect urea hydrolysis, it inhibited
the conversion of NH4(+) to N02C-) and the subsequent oxidation of N02(-) to
N03(-). This resulted in the accumulation of larger amounts of both NH4(+)-N and
N02(-)-N in soil as compared to soil receiving urea alone. The results suggest
that biuret impurity in urea fertilizer is likely to enhance nitrite toxicity.
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77:02G-164
PHOSPHATASES IN SOILS,
Eivazi, F., and Tabatabai, M.A.
Iowa State University, Department of Agronomy, Ames, Iowa 50011.
Soil Biology and Biochemistry, Vol. 9, No. 3, p 167-172, 1977. 4 fig, 4 tab,
26 ref.
Descriptors: Soils, Soil investigations, Soil chemistry, Soil chemical properties,
Phosphates, Alkaline soils.
Most studies on phosphatase activity in soils have been concerned with acid
phosphatase. This study was conducted to determine the activity of phosphomono-
esterases (acid and alkaline phosphatases), phosphodiesterase, and "phospho-
triesterase". The results indicate that acid phosphatase is predominant in acid
soils and that alkaline phosphatase is predominant in alkaline soils. With
universal buffer, the pH optima of phosphodiesterase and phosphotrlesterase were
at pH 10. The activities of these phosphatases in soils were much lower than
those of the acid and alkaline phosphatases. Studies on the effects of various
soil treatments on the activity of phosphatases in soils indicated that air-
drying increased the activity of acid phosphatase and phosphotriesterase, de-
creased the activity of alkaline phosphatase, but did not affect the activity of
phosphodiesterase.
77:02G-165
NITROGEN ISOTOPE DISCRIMINATION IN DENITRIFICATION OP NITRATE IN SOILS,
Blackmer, A.M., and Bremner, J.M.
Iowa State University, Department of Agronomy, Ames, Iowa 50011.
Soil Biology and Biochemistry, Vol. 9, No. 2, p 73-77, 1977. 2 fig, 4 tab, 21 ref.
Descriptors: Nitrogen, Denitrification, Nitrates, Soils, Soil investigations,
Soil chemistry, Isotopes, Soil chemical properties.
Nitrogen isotope discrimination during denitrification in soils of nitrate con-
taining natural concentrations of 14N and 15N was studied by determining the
amount and the 15N content of nitrate-N and (nitrate + nitrite)-N in nitrate-
treated soils incubated under anaerobic conditions (He atmosphere) for various
times after treatment with glucose to promote denitrification. Analyses per-
formed showed that the nitrate-N lost on incubation of these soils could largely
be accounted for as products of denitrification.
77:O2G-166
FACTORS INFLUENCING THE LOSS OF ORGANIC CARBON FROM WHEAT ROOTS,
Martin, J.K.
Commonwealth Scientific and Industrial Research Organization, Division of Soils,
Glen Osmond, South Australia 5064,
Soil Biology and Biochemistry, Vol. 9, No. 1, p 1-7, 1977. 6 tab, 18 ref.
Descriptors: Carbon, Wheat, Root systems, Soils, Soil investigations, Crop
response, Soil microorganisms.
Wheat plants were grown in an atmosphere containing 14C02 at temperatures of 10 C
or 18 C for periods from 3-8 weeks. The plant roots were maintained under sterile
or nonsterile conditions in soil contained in sealed pots which were flushed to
displace respired 14CO2. The 14C content of the shoots, roots and soil was mea-
sured at harvest. The loss of 14C from the roots, expressed either in terms of
total 14C recovered from the pots or 14C translocated to the roots, ranged from
14.3-22.6%, mean 17.3% or 29.2-44.4%, mean 39.2%, respectively.
77:-02G-l 67
NATURE OF THE ORGANIC COATING ON SAND GRAINS OF NONWETTABLE GOLF GREENS,
Miller, R.H., and Wilkinson, J.F.
Ohio State University, Agronomy Department, Columbus, Ohio 43210.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1203-1204, November-
December, 1977. 1 fig, 14 ref.
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Descriptors: Sand, Soils, Soil texture, Soil investigations, Turf, Soil profiles.
The organic coating of nonwettable sand grains from localized dry spots on sand
golf greens was extracted with 5% NaOH. An infrared spectrum of resin purified,
freeze-dried extract was similar to spectra of soil fulvic acids. All other sup-
porting data such as solubility, color, failure to precipitate upon acidification,
noncrystalline nature, and a high extinction coefficient were consistent with the
conclusion that the organic coating was fulvic acid. The relationship of the
synthesis of fulvic acids to basidiomycete hyphae in the affected soil layer is
discussed.
77:02G-168
PHYSICAL PROPERTIES OF FLY ASH-AMENDED SOILS,
Chang, A.C., Lund, L.J., Page, A.L., and Warneke, J.E.
California University, Department of Soil Science and Agricultural Engineering,
Riverside, California 92502.
Journal of Environmental Quality, Vol. 6, No. 3, p 267-270, July-September, 1977.
2 fig, 7 tab, 9 ref.
Descriptors: Fly ash, Soils, Soil investigations. Soil properties, Soil physical
properties, Soil amendments, Soil water, Bulk density, Hydraulic conductivity.
Fly ash from a coal-fired power generating plant was mixed with five California
soils at rates of 0, 2.5, 5.0, 10.0, 25.0, and 50.0% by volume. The physical
properties related to the agronomic use of fly ash-amended soils were character-
ized by determining water-holding capacity, bulk density, hydraulic conductivity,
and modulus of rupture on laboratory compacted soil cores. The moisture release
characteristics of each mixture were also determined. Results indicated that a
small amount of fly ash added to soils does appear to affect some measured physical
properties of soils. At application rates >25%, there was ^ consistent increase
in water-holding capacity (except a Domino loam soil), and a decrease in bulk
density and modulus of rupture in all soils tested. The hydraulic conductivity
increased with small amounts of fly ash, but declined rapidly as fly ash volume
increased. Although fly ash application increased the water-holding capacity of
soils, the amount of water available to the plant did not change significantly.
At a low application rate, fly ash amendment appeared useful in improving certain
agronomic properties of soils.
77:O2G-169
NITRIFICATION IN THREE SOILS AMENDED WITH ZINC SULFATE,
Wilson, D.O.
Georgia University, Department of Agronomy, Georgia Station, Experiment, Georgia
30212.
Soil Biology and Biochemistry, Vol. 9, No. 4, p 277-280, 1977. 3 fig, 2 tab,
11 ref.
Descriptors: Soils, Soil investigations, Zinc, Nitrification, Soil properties,
Soil chemistry, Soil chemical properties, Nitrogen.
The introduction of metals into soils by such routes as land application of
sewage sludge and the deposition of airborne particulates from mining operations
can significantly increase the native soil concentration of these metals. Heavy
metals are commonly present in domestic sewage sludge at rather high concentra-
tions and often at extremely high concentrations in industrial sludges. Elevation
of the metal content of agricultural soils is of particular concern because of
possible toxic effects on plant growth and other biological processes. Zinc is
considered one of the metals most likely to produce phytotoxicity as a result of
sludge application to soil (Webber, 1972). Since soils exhibit a wide range of
physical and chemical properties, it is difficult to compare and extrapolate re-
sults of various workers with respect to the effects of Zn on soil N mineraliza-
tion processes. Reported here are the results of a study relating nitrification
to various rates of Zn added to three agriculturally important soils.
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77:02G-170
ACETYLENE INHIBITION OF NITROUS OXIDE REDUCTION AND MEASUREMENT OF DENITRIFICATION
AND NITROGEN FIXATION IN SOIL,
Yoshinari, T., Hynes, R., and Knowles, R.
Macdonald Campus of McGill University, Department of Microbiology, Ste Anne de
Bellevue, Quebec HOA ICO, Canada.
Soil Biology and Biochemistry, Vol. 9, No. 3, p 177-183, 1977. 9 fig, 1 tab,
Descriptors: Denitrification, Nitrogen, Nutrients, Soil moisture, Soil chemistry,
Soils, Soil investigations.
Reduction of N20 in moist soil was inhibited completely by 10 (-2) atin C2H2 and
partially by 10 (-5) atm C2H2 . The effect of C2H4 was 100,000,000 times less
than that of C2H2. Denitrification of N03(-) occurred in anaerobically or aerobi-
cally incubated waterlogged soil and in anaerobic but not in aerobic moist soil.
77:02G-171
NITROGEN FERTILIZATION I. NITRATE ACCUMULATION AND LOSSES UNDER CONTINUOUS
CORN CROPPING,
Hahne, H.C.H., Kroontje, W., and Lutz, J.A., Jr.
Virginia Polytechnic Institute and State University, Department of Agronomy,
Blacksburg, Virginia 24061.
Soil Science Society of America Journal, Vol. 41, No. 3, p 562-567, May-June,
1977. 4 fig, 5 tab, 30 ref.
Descriptors: Nitrogen, Fertilizers, Fertilization, Nutrients, Corn, Crop response,
Soils, Soil investigations, Irrigation, Irrigation effects, Soil texture.
Selected treatments were chosen from three field experiments with corn to deter-
mine effects of N rates on the vertical distribution of nitrates in the soil.
The experiments were located on three different soil types and corn was grown
for 5 consecutive years. Irrigation was a variable in two of the experiments,
Appreciable amounts of N03-N accumulated in the soils when the optimum rate of
140 kg N/ha at Blacksburg and Charlotte Courthouse and 168 kg N/ha at Orange
had been exceeded. Amounts of vertical distributions of N03-N accumulations
were highly dependent on soil type, and on amounts of irrigation and rainfall.
Lowest N03-N accumulations and highest N03-N losses were encountered in the Cecil
fsl. An increase in NO3-N was found in the Davidson clay loam whereas no loss
or gain was observed in the Groseclose silt loam.
77:02G-172
CHARGE CHARACTERISTICS OF SPODIC HORIZONS,
Laverdiere, M.R., and Weaver, R.M.
New York State College of Agriculture and Life Sciences, Cornell University,
Department of Agronomy, Ithaca, New York 14853.
Soil Science Society of America Journal, Vol. 41, No. 3, p 505-510, May-June,
1977. 5 fig, 5 tab, 22 ref, 2 equ.
Descriptors: Soils, Soil investigations, Soil properties, Organic matter, Ad-
sorption.
Surface charge properties of six Spodosol Bir horizons, enriched in sesquioxides
and organic matter, were investigated by acid-base potentiometric titrations and
ion adsorption measurements. The results indicate that the horizons have electro-
chemical properties similar to constant surface potential colloids as the sign
and magnitude of the net charge were dependent upon the pH and indifferent electro-
lyte concentration of the ambient solution. The pH values at which the net sur-
face charge underwent reversal ranged from 4.2 to 4.9, and the values obtained
by acid-base potentiometric titrations agreed fairly well with those obtained by
ion adsorption measurements.
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77:02G-173.
ERODIBILITY OF SELECTED CLAY SUBSOILS IN RELATION TO PHYSICAL AND CHEMICAL
PROPERTIES,
Romkens, M.J.M., Roth, C.B., and Nelson, D.W.
Agricultural Research Service, Sedimentation Laboratory, Oxford, Mississippi.
Soil Science Society of America Journal, Vol. 41, No. 5, p 954-960, September-
October, 1977. 2 fig, 6 tab, 21 ref.
Descriptors: *Soil erosion, *Subsoil, *Physical properties, *Chemical properties,
*Clays, *Erodibility (subsoils), Laboratory tests, Regression analysis, Chemical
analysis, Soils, Equations, Soil properties, Soil physics, Chemistry.
Predictions of soil erodibility factors for selected clay subsoils were studied
in relation to physical and chemical properties. Erodibility factors were deter-
mined from soil erosion rates on scalped surfaces during a series of simulated
rainstorms. Subsoils were analyzed for their textural, chemical, and mineralogical
composition. A predictive model, derived from previously gathered data of 46
surface soils, was used to determine the significance of soil properties in pre-
dicting subsoil erodibility. Weighted linear regression analysis using data from
surface soils of the test model and 7 selected subsoils indicated that a textural
parameter and the percent of iron plus aluminum extractable with citratedithionite-
bicarbonate (CDB) were significant prediction properties of erodibility for these
clay subsoils. Multiple linear regression yielded a prediction equation with a
coefficient of multiple determination of R sq = 0.90.
77:02G-174
FACTORS INFLUENCING THE CRUST TEST FOR IN SITU MEASUREMENT OF HYDRAULIC CONDUCTI-
VITY,
Baker, F.G.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1029-1032, November-
December, 1977. 1 fig, 5 tab, 14 ref.
Descriptors: *Hydraulic conductivity, *Permeability, *0n-site investigations,
Soil water, Soil water movement, Soils, Soil properties, Soil physics, Soil
physical properties, Testing, Testing procedures, Soil science, Crust tests.
Field trials using the crust test were used to determine the influence of five
parameters on the saturated and unsaturated hydraulic conductivity values measured
on two soils of different structure. These factors were: (1) the diameter, (2)
the height of the soil pedestal used in the test, (3) the degree of soil wetness
at which k was measured, (.4) soil structure, and (.5) operator effects. Diameter
and height were found to strongly affect measurement when they had low values.
These two design factors were dependent on the wetness and structure of the soil.
Operator differences were small.
77:02G-175
SOLUTE DISTRIBUTION PROFILES COMPUTED WITH STEADY-STATE AND TRANSIENT WATER
MOVEMENT MODELS,
Wierenga, P.J.
New Mexico State University, Department of Agronomy, University Park, New Mexico.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1050-1055, November-
December, 1977. 8 fig, 23 ref,
Descriptors: *Hydraulic conductivity, *Solutes, *Soil water movement, *Model
studies, Mathematical models, Moisture content, Pressure head, Fertilizers,
Pesticides, Salts, Irrigation, Dispersion, Analytical techniques, Soil water,
Soil physics, Soil science, Miscible displacement, Finite difference analysis.
A comparison was made between two numerical models for simultaneous movement of
water and salts in soil profiles. In the first model, the water content and flux
were constant during irrigation with time or depth (steady-state model). In the
second model, the water contents and fluxes changed with time and depth following
each infiltration according to the hydraulic properties of the soil (transient
model). From a comparison between data obtained with the two models, it was
shown that both techniques yield comparable results when concentrations are plot-
ted versus cumulative drainage. Measured effluent concentration distributions
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from columns periodically irrigated with labeled water also compared well with
effluent concentration distributions computed with the steady-state model.
77:02G-176
SALT EFFECTS ON THE HYDRAULIC PROPERTIES OF A SWELLING SOIL,
Dane, J.H., and Klute, A.
Colorado State University, Department of Agronomy, Fort Collins, Colorado.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1043-1049, November-
December, 1977. 10 fig, 1 tab, 24 ref.
Descriptors: *Soils, *Soil physical properties, *Hydraulic conductivity, *Salts,
Hydraulic properties, Electrolytes, Salinity, Hydraulic gradient, Tensiometers,
Pressure head, Loads (forces). Water retention, Swelling soil.
The effects of soil solution composition on the hydraulic conductivity, K, and
the volumetric soil solution content, theta, were measured with mixed NaCl-CaC12
solutions. The total electrolyte concentration,. C, and the sodium adsorption
ratio, SAR, characterized the applied solutions. Steady-state flow cells were
constructed with provision for (1) measurement of the volumetric flux of the
solution phase during saturated and unsaturated flow conditions, (2) measurement
of the volumetric soil solution content by gamma attenuation, (.3) tensiometers
for hydraulic gradient and pressure head, h, measurement, (.4) application of an
external load on the soil, and (5) measurement of bulk volume changes. Soil sam-
ples were subjected to sequences of solutions varying in C from 1,000 meq/liter
to 10 meq/liter at constant SAR values of 0, 5, 15, 25, and 40, respectively.
Hydraulic conductivity decreases occurred during the first sequence of decreasing
C at fixed SAT values equal to or greater than 5, The higher the SAR value, the
greater the decrease in K with decreasing C. The K decreases occurred at all
volumetric soil solution contents within the range of experimental data. Increases
in theta, atgiven h values, and decreases in bulk density (pb), occurred simul-
taneously with the decrease in K. Greater changes in K and theta, and smaller
changes in pb occurred in the soil subjected to a higher external load. The K
and pb decreases and the theta increases were to a great extent irreversible, for
example, when C was increased subsequently at a fixed SAR value, K, pb, and theta
did not regain their initial values. Substantial increases in K were obtained,
however, if the soil was air dried, sieved, and repacked into the flow cell.
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SECTION VII
WATER CYCLE
WATER AND PLANTS (GROUP 02I)
77:021-001
EFFECT OF WATER STRESS DURING DIFFERENT STAGES OF GROWTH OF SOYBEAN,
Sionit, N., and Kramer, P.J.
Pahlavi University, Chiraz (Iran).
Agronomy Journal, Vol. 69, p 274-278, March-April, 1977. 5 fig, 1 tab, 15 ref.
Descriptors: *Moisture stress, *Plant growth, *Crop response, *Soybean, Water
requirements, Drought, Flowering, Germination, Photoperiodism, Seeds, Crop
production.
Two varieties of soybean (Glycine max, L, Merr.; "Ransom" and "Bragg") were studied
to determine the effects on yield of controlled water stress at various stages
of development. The plants were grown in a controlled environment chamber at
28/17 C with a 8 9-hour photoperiod at 450 hlx and an interrupted dark period
which was then suspended for 7 days to induce flowering. Water stress was applied
to plant groups during flower induction, flowering, pod formation and pod filling.
Leaf water during stress dropped as low as -23 bars but returned to approximately
normal after rewatering. Leaves were more susceptible to drought at later stages
of growth, probably because they were already approaching senescence. Plants
stressed during flower induction and flowering produced fewer flowers, pods
and seeds than controls because of a shortened flowering period and abortion of
some flowers. The greatest reduction of pods and seeds at harvest was due to
stress during early pod formation, but the yield as measured by seed weight was
most affected by stress during early formation and pod filling. Stress did not
affect the oil or protein content of seeds, although total oil and protein pro-
duced per plant were less because of lower seed yields.
77:021-002
SOIL WATER-ROOT RELATIONS IN WHEAT: WATER EXTRACTION RATE OF WHEAT ROOTS THAT
DEVELOPED UNDER DRY AND MOIST CONDITIONS,
Sharma, R.B., and Ghildyal, B.P.
Leeds University, Department of Plant Sciences, (England).
Agronomy Journal, Vol. 69, p 231-233, March-April, 1977. 2 fig, 2 tab, 8 ref.
Descriptors: *Soil water, *Soil-water-plant relationships, *Root systems, *Ab-
sorption, *Wheat, Dry farming, Soil moisture, Soil water movement, Clay loam,
Root development, Root zone, Plant morphology, Consumptive use.
A greenhouse experiment was conducted in Pantnagar, India, to determine whether
the root systems of wheat grown under different soil water conditions differed
in capacity to extract water from the soil. The water extraction rate per unit
root volume was measured for two wheat (Treticum aestivum L.) genotypes grown
for 60 days after sowing in pots maintained under three soil water tension re-
gimes of 0.3-0.8, 2.0-2.5, and 4.0-4.5 bars. Under study were the one-gene
dwarf Snalika RR-21 and three-gene drawf UP 301; the soil was silty clay loam
of the Mollisol order. Sixty days after sowing, the transpirational losses
under different soil water tension regimes were measured for 12 days by cover-
ing the pots with polyethylene sheet and weighing. Root volume and total root
water extracted decreased significantly for both genotypes. Results suggest
that root systems which develop under relatively dry soil conditions extract
more soil water on a unit root volume basis than those in moist conditions.
Findings also indicate that roots under dry conditions develop a more intricate
morphology and exploit the soil water more completely.
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77:021-003
SIMULATION OF NITROGEN MOVEMENT, TRANSFORMATIONS, AND PLANT UPTAKE IN THE ROOT
ZONE,
Davidson, J.M., Rao, P.S.C., and Selim, H.M,
Florida University, Department of Soil Science, Gainesville, Florida.
Proceedings of National Conference on Irrigation Return Flow Quality'Management,
Colorado State University, Fort Collins, Colorado, p 9-18, May 16-19, 1977.
7 fig, 1 tab, 28 ref, 13 equ.
Descriptors: Simulation analysis, Model studies, Nitrogen, Soil water, Soil
water management, Irrigation, Nitrification, Denitrification, Mineralization.
Two simulation models, a detailed research-type and a conceptual management-
type, for describing the fate of nitrogen in the plant root zone are discussed.
Processes considered in both models were: one-dimensional transport of water
and water-soluble N-species as a result of irrigation/rainfall events, micro-
biological N-transformations, and uptake of water and nitrogen species by a
growing crop_. The research-type model involves a finite-difference approxima-
tions (explicit-implicit) of the partial differential equations describing one-
dimensional water flow and convective-dispersive NH4 and N03 transport, along
with simultaneous plant uptake and microbiological N-transformations, Ion-
exchange (.adsorption-desorption) of NH4 was also considered. The microbiological
transformations incorporated into the model describe nitrification, denitrifi-
cation, mineralization and immobilization. All transformation processes were
assumed to be first order kinetic processes. The numerical solution was flexible
in its soil surface boundary conditions, as well as initial conditions for soil
water content and nitrogen concentration distributions in the soil profile. The
solution can also be used for nonhomogeneous or multilayered soil systems. The
research-type model involves a detailed description of the individual process
and requires a large number of input parameters, most of which are frequently
unavailable. Because of this a more simple management-type model was developed.
Several simplifying assumptions were introduced into the management model. This
model requires a minimal amount of input data by the user, and provides a gross
description of the behavior of various nitrogen species in the plant root zone.
77:021-004
LOCAL SOLUTIONS TO DRAINAGE PROBLEMS,
Johnstone, W.R.
Westlands Water District, Fresno, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 293-295, May 16-19, 1977.
Descriptors: Saline water, Salinity, Return flow, Drainage water,
Throughout the San Joaquin Valley the installation of on-farm tile systems can
intercept and collect saline subsurface drainage water and thereby reduce or
eliminate the damage from high water tables. Five subareas in the San Joaquin
and Tulare Lake Basins of the San Joaquin and Tulare Lake Basins of the San
Joaquin Valley have individually developed local solutions for disposing of
saline subsurface drainage water collected within the subareas,
77:021-005
RESPONSE OF LEAF WATER POTENTIAL TO PRESSURE CHANGES AT THE ROOT SURFACE OF
CORN PLANTS,
Nulsen, R.A., Thurtell, G.W., and Stevenson, K.R.
Guelph University, Department of Land Resource Science, Ontario, Canada, NIG 2WI.
Agronomy Journal, Vol. 69, No. 6, p 951-954, November-December, 1977. 4 fig,
15 ref.
Descriptors: Roots, Root systems, Corn, Soil water, Soil moisture, Transpiration,
Crop response.
The nature of the hydraulic continuum between the roots and leaves of intact
plants requires further study to improve our understanding of the effect of _
pressure changes. A large pressure chamber was designed to apply hydrostatic
pressure to the roots of intact corn plants. The chamber permitted application
of up to 6 bars pressure and allowed for in situ watering of the plants. Changes
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in leaf water potential resulting from changes in pressure applied to the roots
were monitored in situ using a thermocouple dewpoint hygrometer. Responses of
leaf water potential were consistently between 0.94 and 1.19 times the change
in applied pressure, regardless of whether the pressure was being increased or
decreased. When pressure was applied to very turgid plants, leaf water potential
increased until it reached a value equal to the osmotic pressure of expressed
xylem sap. Some time after this value was reached water droplets appeared on
the leaf surface. The experiments showed that the hydraulic system within in-
tact plants acts as a true continuum in that pressure changes at one end of the
system are faithfully manifested at the other end of the system. If such
changes are not observed some additional mechanism must be operating.
77:021-006
CROP SALT TOLERANCE CURRENT ASSESSMENT,
Maas, E.V., and Hoffman, G.J.
United States Department of Agriculture, Agricultural Research Service, United
States Salinity Laboratory, Riverside, California.
Journal of the Irrigation and Drainage Division, American Society of Civil Engi-
neers, Vol. 103, No. IR2, p 115-134, June 1977. 1 fig, 1 tab, 160 ref.
Descriptors: Salts, Salt tolerance, Agriculture, Crop response, Salinity, Saline
soils, Saline water.
An extensive literature review of all available salt tolerance data was undertaken
to evaluate the current status of our knowledge of the salt tolerance of agri-
cultural crops. In general, crops tolerate salinity up to a threshold level above
which yields decrease approximately linearly as salt concentrations increase. Our
best estimate of the threshold salinity level and yield decrease per unit salinity
increase is presented for a large number of agricultural crops. The methods of
measuring appropriate salinity and plant parameters to obtain meaningful salt
tolerance data and the many plant, soil, water, and environmental factors influ-
encing the plant's ability to tolerate salt are examined,
77:021-007
ROLE OF CHANGES IN SOLUTE CONCENTRATION IN MAINTAINING FAVORABLE WATER BALANCE
IN FIELD-GROWN COTTON,
Cutler, J.M., Rains, D.W., and Loomis, R.S.
California University, Department of Agronomy and Range Science, Davis, California.
Agronomy Journal, Vol. 69, No. 5, p 773-779, September-October, 1977. 5 fig,
49 ref.
Descriptors: Cotton, Crop response, Soil water, Soil moisture,. Irrigation, Ir-
rigation effects, Crop production, Agriculture,
Cotton shows various adaptive responses to water deficits, including alterations
in cellular osmotic concentrations. The role of changes in solute concentration
in maintaining favorable water balance in field-grown cotton was evaluated under
wet and dry irrigation treatments. The experiments were conducted with a fine
loamy mixed, calcareous thermic-Typic Torriorthents soil in a semi-arid environ-
ment. Leaf diffusive resistance, measured by a resistance porometer, was unaf-
fected by leaf water potential while the typical response to light was maintained.
Leaf blade elongation rate was less in plants with low leaf water potential. The
rate was maximal in the early evening and depressed during the midday water poten-
tial minimum and at night. Some blade enlargement occurred during time intervals
when leaf water potentials were as low as -19 to -23 bars,
77:021-008
TRANSPIRATION EFFECTS ON LEACHING FRACTIONS,
Meiri, A., Kamburov, J., and Shalhevet, J.
The Volcani Center, Agricultural Research Organization, Bet Dagan, Israel,
Agronomy Journal, Vol. 69, No. 5, p 779-782, September-October, 1977, 2 fig,
2 tab, 9 ref.
Descriptors: Leaching, Infiltration, Soil water, Soil moisture, Soil water
movement, Saline water, Irrigation water, Salinity, Salts, Seepage,
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Water uptake by plants during the processes of infiltration and redistribution
may introduce considerable errors in actual leaching when calculations are
based on pre-irrigation soil water deficit. The objective of the study reported
here was to measure and demonstrate the importance of this water uptake in
causing a reduction in the actual leaching.
77:021-009
ESTIMATING LEAF WATER POTENTIAL IN SAFPLOWER,
Sepaskhah, A.R.
Pahlavi University, College of Agriculture, Department of Irrigation, Shiraz, Iran.
Agronomy Journal, Vol. 69, No. 5, p 894-896, September-October, 1977. 1 fiq
14 ref.
Descriptors: Crop production, Greenhouses, Laboratory tests, Laboratory equip-
ment, Leaves.
The pressure chamber technique is used for rapid measurements of plant water
potential. Comparison of this method with thermocouple psychrometer technique
is required at various stages of growth for different crops. Xylem water po-
tential estimated by pressure chamber and leaf water potential measured by
thermocouple psychrometer were correlated for safflower leaves at vegetative
and flowering stages of growth in greenhouse conditions, The results of the
two methods were linearly related for both growth stages but the equations were
different at the 1% level. The values of ordinate intercept were nearly equiva-
lent to the xylem sap osmotic potentials at both stages of growth.
77:021-010
RESPONSE OF OATS TO WATER DEFICIT. I. PHYSIOLOGICAL CHARACTERISTICS,
Sandhu, B.S., and Horton, M.L.
South Dakota State University, Department of Plant Science, Brookings, South
Dakota.
Agronomy Journal, Vol. 69, No. 3, p 357-360, May-June, 1977. 6 fig, 21 ref.
Descriptors: *0ats, *Moisture stress, *Moisture deficit, *Plant physiology,
*Crop response, Growth stages, Stomata, Soil-water-plant relationships, Photo-
synthesis, Irrigation practices, Plant growth, Planting management, Leaves.
A study was conducted to determine the effects of water stress on certain physio-
logical processes of spring oats (Avena sativa L.) under field conditions. Plants
were subjected to water deficits for 9 to 11 days at the boot stage, at anthesis
through early grain formation stage and at both stages in combination. Relative
leaf water content (RLWC) according to the relative turgidity method was used as
a measure of water deficit, and a diffusion porometer was used to monitor lead
diffusion resistance (LDR). An 80% decline in the net photosynthetic rate (NPR),
as measured using an infrared gas analyzer, resulted from severe water stress at
all stages. A decline in RLWC was followed by LDR increases, due to siomatal
closure induced by water deficits. Both LDR and RLWC recovered in 1 to 6 days
after rewatering. Stress during the boot stage reduced photosynthetic sensiti-
vity to subsequent stress at the anthesis through early grain formation stage,
with NPR recovering more gradually and incompletely after that. Plants stressed
only during the boot stage, then adequately watered, had higher NPR than controls.
Since the LDR and NPR of oats have acute sensitivity to plant water deficits,
these parameters may help determine permissible water deficit limits and irriga-
tion scheduling.
77:021-011
RESPONSE OF OATS TO WATER DEFICIT. II. GROWTH AND YIELD CHARACTERISTICS,
Sandhu, B.S., and Horton, M.L.
South Dakota State University, Department of Plant Science, Brookings, South Dakota.
Agronomy Journal, Vol. 69, No. 3, p 361-364, May-June, 1977. 5 tab, 19 ref.
Descriptors: *Crop response, *0ats, *Moisture deficit, *Plant growth, *Crop
production, Moisture stress, Plant physiology. Growth stages, Root development,
Root distribution, On-site investigations, Height, Planting management, Soil-
water-plant relationships, Stomata.
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Spring oats (Avena sativa L.) were subjected to water stress for 9 to 11 days
under field conditions to evaluate growth and yield response to water deficits
at certain stages. Plants were grown on pachic udic haploborolls soil (Lismore
silty clay loam) in large pots (120-litre garbage cans) buried in the center of
a field. Water stress applied at the boot stage and/or the anthesis through
early grain formation stage decreased plant height and number of florets per
panicle. Stress at anthesis through early grain formation caused more floret
sterility and fewer heads at maturity. Deficits at all stages decreased the
yield of straw, tops without panicles, panicles, kernels and dehulled kernels.
Kernel yield was depressed 20% and 58%, respectively, with stress at booting
and anthesis through grain filling; combined stress caused 67% yield decline.
Plants under soil water stress rooted to a greater depth and had accelerated
growth and profuse tillering when rewatered. Management under both dryland
and irrigated conditions should emphasize irrigation during the anthesis through
early grain formation stage, when water stress is especially dangerous,
77:021-012
PREDICTION OF LATE SEASON NITRATE-NITROGEN CONTENT OF SUGARBEET PETIOLES,
Giles, J.F., Ludwick, A.E., and Reuss, J.O.
South Dakota State University, James Valley Research and Extension Center,
Redfield, South Dakota 57469.
Agronomy Journal, Vol. 69, No. 1, p 85-88, January-February, 1977, 6 fig, 1
tab, 8 ref.
Descriptors: Nitrates, Nitrogen, Sugarbeets, Nutrients, Fertilizers, Fertili-
zation, Colorado.
Nitrate nitrogen levels in sugarbeet petioles have been used as an aid to diag-
nose nutritional status of the plants. The purpose of this study was to evalu-
ate a theoretical approach to the prediction of the rate of, change in N03(-)N
concentration of sugarbeet petioles. Petiole samples were collected from
sugarbeet N fertilizer trails conducted over a 2-year period on cooperator
farm sites in central and eastern Colorado. Results showed the NO3(-)N concen-
tration of sugarbeet petioles through the growing season decreased exponentially.
The rate of change was a function of soil NO3(-)N content (0-120 cm depth)
measured in the spring and the amount of N applied as preplant fertilizer. Cal-
culation of the rate of change with this function and the measurement of one
early petiole sample enables the prediction of the NO3(-)N concentration during
the remainder of the growing season.
77:021-013
INTERACTIONS OF LEAD AND CADMIUM ON METAL UPTAKE AND GROWTH OF CORN PLANTS,
Miller, J.E., Hassett, J.J., and Koeppe, D.E.
Argonne National Laboratory, Argonne, Illinois.
Journal of Environmental Quality, Vol. 6, No. 1, p 18-20, January-March, 1977.
4 tab, 21'ref.
Descriptors: Lead, Cadmium, Heavy metals, Crop response, Corn, Crop production,
Greenhouses.
Short term plant accumulation and growth effects of Pb and Cd added to soil
separately and in combination were investigated with corn grown in a loamy
sand under greenhouse conditions. A tendency for soil Pb to increase both the
plant Cd concentration and the total Cd uptake of the corn shoots was observed.
Conversely, soil Cd reduced the total Pb uptake and in some cases the Pb con-
centration in the corn shoots. Both Pb (125 and 250 mu g/g soil) and Cd (2.5
and 5 mu g/g soil) reduced the vegetative growth of the corn shoots, and a posi-
tive interaction of the two metals on growth was noted.
77:021-014
WATER UPTAKE BY PLANTS: I. DIVIDED ROOT EXPERIMENT,
Herkelrath, W.N., Miller, E.E., and Gardner, W.R,
United States Geological Survey, Water Resources Division, 345 Middlefield Road,
Menlo Park, California 94025,
Soil Science Society of America Journal, Vol. 41, No, 6,, p 1033-1038, November-
December, 1977. 13 fig, 22 ref, 5 equ.
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Descriptors: Soil water, Soil moisture, Root systems, Root zone, Root development,
Crop production.
The influence of soil water content and soil water potential upon root water up-
take was investigated in a controlled laboratory environment. Water extraction
rates by roots of winter wheat were measured in situ in a soil column instru-
mented with a gamma-ray attenuation water-content meter, tensiometers, and psychro-
meters. In addition, the leaf water potential was measured with an in situ leaf
hygrometer. In order to measure the vertical distribution of water uptake, the
column was divided into five sections by wax layers which were penetrated by roots,
but which prevented movement of water between sections in the soil.
77:021-015
WATER UPTAKE BY PLANTS: II. THE ROOT CONTACT MODEL,
Herkelrath, W.N., Miller, E.E,, and Gardner, W.R.
United States Geological Survey, Water Resources Division, 345 Middlefield Road,
Menlo Park, California 94025.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1039-1042, November-
December, 1977. 7 fig, 1 tab, 6 ref.
Descriptors: Model studies, Root development, Root systems, Soil water. Soil
moisture, Simulation analysis.
In the standard analysis of root water uptake, it is assumed there is a constant
root membrane resistance in series with a soil resistance which is dependent upon
the soil moisture diffusivity- The relation of root extraction rate to soil water
content and to soil water potential predicted by this standard model was compared
to the results of divided root experiments. The extraction rates predicted by
the theory were as much as eight times larger than the measured values. A reason-
able fit between theory and experiment could only be obtained by assuming in the
theoretical calculations that the rooting density was 100 times smaller than that
measured in the experiments,
77:021-016
IRRIGATION APPLICATION DEPTHS FOR OPTIMUM CROP PRODUCTION,
DeBoer, D.W., Brosz, D.D., and Wiersma, J.L.
South Dakota State University, Department of Agricultural Engineering, Brookings,
South Dakota.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 1067-1069, December 20, 1977, 4 fig, 4 tab.
Descriptors: Sprinkler irrigation, Soil moisture, Corn, Crop production, Grains
(crops), Application methods, Water utilization, Surface irrigation, Irrigation
water, Evapotranspiration, South Dakota, Tensiometers,
Corn was irrigated using three (2.5 cm, 5.0 cm and 7.5 cm) net irrigation depths
to determine the effect of application depth on grain yield, water utilization
efficiency and soil water movement. Grain yields and water utilization efficiencies
were not affected by the application depths. The average rate of water removal
from a 90 cm soil profile during July and August was 0,54 cm/day,
77:021-017
WATER RELATIONS OF COTTON. II. CONTINUOUS ESTIMATES OF PLANT WATER POTENTIAL
FROM STEM DIAMETER MEASUREMENTS,
Buck, M.G., and Klepper, B.
United States Department of Agriculture, Aaricultural Research service, Southern
Region,
Agronomy Journal, Vol. 69, No, 4, p 593-597, July-August, 1977. 3 fig, 19 ref,
Descriptors: Cotton, Sampling, Crop response, Plant growth, Plant physiology,
Plant population.
Information about plant water potential is often required at very frequent inter-
vals in studies with small numbers of plants. Two methods for inferring plant
water potential continuously and nondestructively are described for cotton plants,
Both methods require continuous monitoring of stem diameter and occasional de-
structive sampling of tissue for determination of water potential by conventional
methods. The computed results are compared with experimental measurements of
plant water potential.
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77:021-018 ,
COMPARATIVE STUDIES OF SOME INLAND SALINE AQUATIC ECOSYSTEMS IN NORTH DAKOTA,
Wall, M.K.
North Dakota University, Department of Biology, Project Reclamation, Grand Forks,
North Dakota.
North Dakota Water Resources Research Institute, Research Project Technical Com-
pletion Report, Part 1, Report Number WI-221-033-76, Project Number A-031-NDAK,
July 1970- June 1974, p. 1-58. 19 fig, 15 tab, 61 ref, 1 append.
Descriptors: North Dakota, Ecosystems, Saline water, Dissolved oxygen, Sediment-
water interfaces, Saturation, Sediments, Sampling, Trace elements, Biomass,
Temperature, Sago pondweed.
Potamogeton pectinatus L. is a very important wildlife food species, a submerged,
marl forming macrophyte and grows as a natural monospecies community in Fox Lake,
North Dakota. The water, sediment, dissolved oxygen, temperature and productivity
relationships were studied in this small, shallow lake. The characteristics of
aerobic and anaerobic sediments in Fox Lake and the North Dakota transect are dis-
cussed in terms of their effects on the nutrient concentrations. Chelation of
cations by dissolved organic materials in the water and absorbed on the marl was
found to be a possibility, especially for trace elements. Carbonate (marl) forma-
tion and bicarbonate utilization were found to be of major importance in the main-
tenance and productivity of the monotypic P. pectinatus community in Fox Lake.
77:021-019
EFFECT OF REDOX POTENTIAL AND PH ON THE UPTAKE OF CADMIUM AND LEAD BY RICE PLANTS,
Reddy, C.N., and Patrick, W.H., Jr.
Louisiana State University, Department of Agronomy, Baton Rouge, Louisiana 70803.
Journal of Environmental Quality.- Vol. 6, No. 3, p 259-262, July-September, 1977.
8 fig, 2 tab, 21 ref.
Descriptors: Cadmium, Lead, Rice, Heavy metals, Sediments, Saturated soils.
Redox potential and pH are two of the major factors influencing the mobilization
and immobilization of heavy metals in flooded soils and sediments, and their
availability to plants. A system developed for growing plants in soil suspensions
where redox potential and pH can be controlled was used to study the uptake of
cadmium (Cd) and lead (Pb) by rice plants. Uptake of Cd and Pb by root and shoot
tissue, and their translocation from root to shoot, was determined at six dif-
ferent redox potentials (-200, -100, 0, +100, +200, and +400 mV) and four pH
values (5, 6, 7, and 8). The effects of redox potential and pH on the levels of
water-soluble Cd and Pb in the soil suspensions were also studied. Almost all
Cd entering the rice plants accumulated in the shoots. Total Cd uptake and shoot
uptake increased with an increase in suspension redox potential and a decrease in
pH. Water-soluble Cd in the soil suspension was significantly correlated with
total plant Cd and Cd uptake by shoot. Total Pb uptake, including Pb associated
with the roots, decreased with an increase in suspension redox potential and pH,
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SECTION VIII
WATER CYCLE
EROSION AND SEDIMENTATION (GROUP 02J)
77:02J-001
USE OF A VERSATILE EXPERIMENTAL SYSTEM FOR SOIL EROSION STUDIES,
Walker, P.H., Hutka, J,, Moss, A.J,, and Kinnell, P.I.A.
Commonwealth Scientific and Industrial Research Organization, Division of Soils,
Canberra (Australia).
Soil Science Society of America Journal, Vol. 41, No. 3, p 610-612, May-June,
1977. 3 fig, 10 ref.
Descriptors: *Soil erosion, *Simulated rainfall, *Laboratory tests, Sheet erosion,
Erosion, Erosion rates, Raindrops, Slopes, Streams, Runoff, Sediment transport,
Bed load. Discharge (sediments), Rainfall, Rainfall simulators, Impact (rainfall),
Soil science.
A laboratory facility for the study of soil erosion was described. Rainfall from
a modular system supplied raindrops at near terminal velocity to prepared soil beds
set in a flume with slope adjustable up to 30%. A comparison was made of erosion
under overland flow alone and of storm rains of the same intensity (discharge),
but of different energy levels. Raindrop impact in runoff flow was a powerful
agency in promoting, soil transport and inhibiting rill formation. Bed load move-
ment was important in the transport of sand grains, even where the runoff was dis-
turbed by raindrops.
77:02J-002
BED LOAD SAMPLER FOR STREAMS WITH SANDY BED,
Racotch, A., and Sagi, R.
Technion-Israel Institute of Tech., Faculty of Agricultural Engineering, Haifa (Israel)
Journal of the Hydraulic Division, American Society of Civil Engineers, Vol. 103,
No. HY8, p 923-928, August 1977. 3 fig, 9 ref, 1 append.
Descriptors: *Bed load samplers, *Sampling, *Equipment, *Sediment transport, Bed
load, Beds, Streams, Streamflow, Sands, Sediments, Sedimentation, Sedimentology.
Technical and operational considerations led to the idea of using a simple pit
sampler in combination with a weighting instrument as a possible and inexpensive
arrangement for bed load measuring purposes. In order to avoid large construction
and collecting containers, it was decided to design the opening/instrument combi-
nation for particles having nominal (diameter of spheres that equal the number
of particles considered and their total volume) diameters less than 3 mm, making
the unit suitable for streams with sandy beds. The proposed instrument was de-
scribed. The sensing element is built in the form of a bucket, subdivided into
two compartments and pivoted over a knife edge. The bucket tips whenever one of
the compartments f,ills up to a preset quantity of material. The material is tip-
ped into the collecting container and the empty compartment is simultaneously
exposed to the material entering the opening. The design of the shape and the
dimensions of the bucket were based on an analytical investigation of a mathemati-
cal model. The analysis permitted determination of the parameters of the bucket
and the position of the pivot. Emphasis was placed on automatic performance of
the whole system in the sense that no person has to assist the measuring unit at
the time of operation.
77:02J-003
INCIPIENT TRANSPORT OF FINE GRAINS AND FLAKES BY FLUIDS-EXTENDED SHIELDS DIAGRAM,
Mantz, P.A.
Imperial College of Science and Technology, Department of Civil Engineering,
London (England).
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY6, Proceedings Paper 12992, p 601-615, June 1977. 4 fig, 3 tab, 30 ref, 2
append. nn
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Descriptors: *Bed load, *Hydraulics, *Sedimentation, *Shear stress, *Cohesionless
soils, Streamflow, Silts, Laboratory tests, Sediments, Data collections.
Experiments on the incipient transport from flat sediment beds in water streams of
four grades of fine cohesionless granular solids and six grades of fine cohesionless
flaky solids were reported. The fine granular data were compared with data obtained
from recent smaller-scale laboratory experiments, and all data were plotted on a
Shields diagram. An "extended Shields diagram," which is applicable to cohesionless
solids only, was proposed. The fine flaky data were compared with collected data
concerned with the incipient transport of coarse two-dimensional solids or flakes.
The data again were adapted to the Shields representation. The incipient transport
fluid conditions for granular and flaky solids (which solids were chosen as being
representative of extreme shape limits) were contrasted.
77:02J-004
CHANGING NEEDS AND OPPORTUNITIES IN THE SEDIMENT FIELD,
Wolman, M.G.
Geological Survey, Water Resources Division, Baltimore, Maryland.
Water Resources Research, Vol. 13, No. 1, p 50-54, February 1977. 21 ref.
Descriptors: *Sedimentation, *Erosion, *Sediment transport, *Sediment yield,
Reviews, Evaluation, Model studies, Hydrologic properties, Hydrologic data,
Environmental effects.
Information on the processes of erosion and sedimentation, while sometimes suf-
ficient for gross estimates of yield, remains inadequate for modern environmental
management. Little is known about sequential processes involved in the systems
of erosion and sedimentation, and practice and theory require attention to unsteady
or discontinuous erosion and transportation as sediments move from source through
channel systems with intermittent periods of storage. While climatic and hydro-
logic variations markedly affect yield, transport and deposition thresholds of
erosion of cohesive materials and sequences of such effects remain unclear. The
highly variable temporal and spatial character of erosion and sedimentation pro-
cesses must be emphasized in the predictive exercise of environmental impact
assessment. Validation or testing of the predictive capacity of our current know-
ledge can only be achieved by field observation. This does not imply massive
data collection programs but rather an integration of model building, laboratory
study, and continuity of study in carefully selected field areas.
77:02J-005
DETERMINATION OF SEDIMENT YIELD BY TRANSFERRING RAINFALL DATA,
Smith, J.H., Davis, D.R., and Fogel, M.
Arizona University, Department of Systems and Industrial Engineering, Tucson,
Arizona.
Water Resources Bulletin, Vol. 13, No. 3, p 529-541, June 1977. 2 fig, 17 ref.
Descriptors: *Sediment yield, *Reservoir silting, *Model studies, *Arizona,
Rainfall, Reservoir storage, Reservoirs, Dead storage, Decision making. Equations,
Risks, Mathematical studies, Numerical analysis, Methodology, Estimating, Sediment
discharge.
A methodology for obtaining the optimal design value to allow for sediment storage
in a reservoir was presented for the situation where no data on sediment loads in
the incoming streams are available. Information concerning the amount of sediment
delivered to the reservoir over its lifetime was obtained by a sediment yield model
which uses data on rainfall amount and duration obtained from a nearby experimental
watershed. Bayesian Decision Theory was used to obtain the optimal storage re-
quirements in order to consider the natural variation of rainfall and the sampling
error due to the short rainfall record available. The normally difficult calcula-
tions involved were made tractable by the use of simplifications and approximations
which were valid in the context of the problem. Results showed that sediment
storage requirements can be calculated in this manner and that consideration of
the uncertainties involved leads to a shortage requirement substantially larger
than that calculated without such consideration.
100
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77:02J-006
MANAGEMENT GUIDELINES FOR CONTROLLING SEDIMENTS, NUTRIENTS, AND ADSORBED BIOCIDES
IN IRRIGATION RETURN FLOWS,
Carter, D.L., and Bondurant, J.A.
United States Department of Agriculture, Snake River Conservation Research Center,
Kimberly, Idaho.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 143-152, May 16-19, 1977.
3 tab, 36 ref, 2 equ.
Descriptors: Furrow irrigation. Sediments, Return flow, Erosion, Nutrients,
Surface irrigation, Runoff, Irrigation, Tailwater, Irrigation systems.
Sediments in irrigation return flows arise mostly from furrow erosion, and nearly
all nutrients and biocides in surface irrigation return flows, except those applied
directly to the water, are adsorbed to the sediments. Therefore, controlling
erosion and sediment loss in these surface return flows also controls the nutrients
and biocides. There are three general management approaches for controlling sediments
in return flows. The first is to eliminate surface runoff by using irrigation methods
that produce no runoff. These methods include properly designed and operated
sprinkler systems, basin, trickle, and some border and level furrow methods. The
second approach is to eliminate or reduce erosion by controlling the slope in the
direction of irrigation, the furrow stream size, the run length, the irrigation
frequency and duration, and tillage practices. The third is to remove sediments
from surface return flows by controlling the tailwater and utilizing sediment
retention basins. All three approaches are applicable and necessary for adequate
control in most irrigated areas. Available technology needs to be integrated
and applied to these approaches. Research to develop improved irrigation systems
and methods, improved irrigation water distribution systems, and better field
management practices, and research on design and operational criteria for sediment
retention basins are needed.
77:02J-007
ECONOMIC ANALYSIS OF ON-FARM METHODS FOR CONTROLLING SEDIMENT AND NUTRIENT LOSSES,
Lindeborg, K.H., Conklin, L., Long, R.B., and Michalson, E.L,
Idaho University, Moscow, Idaho,
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 193-201, May 16-19, 1977.
16 tab, 3 ref.
Descriptors: Idaho, Model studies, Irrigation practices, Crop production, Erosion,
Sedimentation, Irrigation, Water quality, Phosphorus, Nitrogen, Groundwater,
Pollution.
Information from 150 farmers in the Boise and Magic Valley areas was collected
relative to current crop production, tillage and irrigation practices, cost of
production, and income from crop production. The physical and economic data were
processed by a budget generating method allowing standardized procedures of
estimating costs of operating machinery and equipment. Partial budgets for each
important crop grown in the two areas were developed from the computer program.
Representative farms were simulated for the two areas based on the partial budgets,
The simulated farm sizes will be a measure of the profitability of the present
farming operation under existing water management practices. The effects on farm
net income of implementing erosion control practices on the farms, as well as by
district, are analyzed using linear programming models. The analysis is based on
two farm sizes in each area, and measures the effects on net farm income for a
given set of rotation with increasing sedimentation loss, or alternately, a
changing cropping pattern with a given lower limit of sediment loss with the re^
suiting change in farm net income.
77:02J-008
NUTRIENT LOSSES IN SURFACE RUNOFF FROM A NATIVE PRAIRIE,
Timmons, D.R., and Holt, R.F.
United States Department of AgricultureAgricultural Research Service, North
Central Soil Conservation Service, Morris, Minnesota 56267,
Journal of Environmental Quality, Vol. 6, No, 4, p 369-373, October-December,
1977. 5 tab, 22 ref.
101
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Descriptors: Nutrients, Fertilizers, Fertilization, Runoff, Minnesota, Snowmelt,
Rainfall, Rainfall-runoff-relationships, Nitrogen, Phosphorus, Potassium, Sodium,
Calcium, Chemical oxygen demand.
Nutrient losses in surface runoff from a native prairie were determined for 5
years. The prairie, dominated by little bluestem was on a Barnes loam soil in
west-central Minnesota. Snowmelt runoff accounted for 80% of the average annual
runoff. After spring thaw, rainfall caused appreciable runoff (37% of annual)
during 1 year only- Depending on chemical parameter, 63 to 88% of the average
annual nutrient loads were transported by snowmelt runoff. Average annual total
nitrogen (N) and total phosphorus (P) losses were 0.8 and 1.1 kg/ha, respectively,
and organic N and organic (+ hydrolyzable) P comprised 68 and 82% of their
respective annual losses. Average annual cation losses ranged from about 0,1
to 1.8 kg/ha and, except for 1 year, were in the order K>Ca>Mg>Na, Average
weighted concentrations for all parameters were higher for rainfall runoff than
for snowmelt runoff. Nutrient losses from native prairie represent natural
levels for comparing the effects of different land uses on nutrient loads in
surface runoff.
77:02J-009
SOIL LOSS: AN OVERVIEW,
Kovda, V.A.
Moscow State University, Institute of Agrochemistry and Soil Science, Moscow
Region, Union of Soviet Socialist Republics.
Agro-Ecosystems, Vol. 3, No, 3, p 205-224, June 1977, 3 tab, 12 ref.
Descriptors: Soils, Soil investigations, Soil erosion,. Soil environment, Soil
engineering, Soil management, Soil science, Environment, Land resources, Land
management, Land use.
The earth's soil budget is analyzed and the causes of loss and degeneration are
described. The main efforts to solve the problems of soil loss should be con-
centrated on: (a) the preparation of international guidelines for conservation
policy; (b) declaration of an International Soil Conservation Decade; and (c)
acceleration of and support for land assessment; (d) development of national
planning for alternative land uses; (.e) research to establish ecologically
sound policies for land use and conservation.
77:02J-010
ERODIBILITY OF SOME MINNESOTA SOILS,
Young, R.A,, and Mutchler, C.K,
Agricultural Research Service, Morris, Minnesota.
Journal of Soil and Water Conservation, Vol. 32, No. 3, p 1807-182, July 1977.
3 tab, 22 ref.
Descriptors: *Erosion, *Minnesota, *Soils, *Erosion rates, *Soil erosion, Runoff,
Bulk density, Equations, Silts, Montmorillonite, Hydrology.
Soil erodibility factors from 13 Minnesota soils were calculated based on mea*-
sured soil loss and on runoff from standard simulated rainstorms. Regression
analysis of erodibility on 10 soil characteristics plus runoff indicated that
5 soil variables-aggregate index, dispersion rate, bulk density, percent silt
and very fine sand, and amount of montmorillonite in the soil-explained 90% of
the variance in the calculated K values. When currently used K values obtained
from the soil erodibility nomograph and SCS determinations were compared with
the calculated K values, it was found that the currently used values under-
estimated the erodibility of 6 and overestimated the erodibility of 3 of the
13 soils tested.
77:02J-011
HELLEY-SMITH BED LOAD SAMPLERS,
Johnson, C.W., Engleman, R.L., Smith, J.P., and Hanson, C.L.
Agricultural Research Service, Boise, Idaho,
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY10, p 1217-1221, October 1977, 2 fig, 1 tab, 9 ref, 1 append.
102
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Descriptors: *Bed load samplers, *Sampling, *ldaho, *0n-site investigations,
*Sediment load. Instrumentation, Demonstration watersheds, Equipment, Sediment
transport, Sediments, On-site tests, Testing, Testing procedures, Measurement.
This paper reported recent findings and experiences in using Helley-Smith bed
load samplers in streams on the Reynolds Creek Experimental Watershed in south-
west Idaho. Equipment and procedures developed in sampling during peak stream-
flow events were described. The 90-sq mile sagebrush rangeland watershed, with
a main stream length of 16 miles (25,7 km), an elevation difference of 3,700
ft (1,130 m) , and average streamflow rate of 21.5 cfs, is characterized by steep
gravel-boulder streambeds with many outcrops of basalt and granite. The streams
transport large quantities of sediment during rainfall and snowmelt events. Users
of Helley-Smith bed load samplers, under conditions of high organic and sediment
transport, should recognize the possible sampling error caused by clogging of
standard sampler bags and instead use either larger bags or bags with a mesh
larger than 0.2 mm. The samplers with standard small 0,2 mm mesh bags clogged
very easily and drastically affected the sediment catch. The large sampler
bags with 930 sq in of bag area, instead of 340 sq in caused no sampler operation
problems and allowed sampling for longer periods to obtain larger samplers.
Large 0.2 mm mesh bags are recommended for most uses,
77:02J-012
PROCEEDINGS OF THE NATIONAL SYMPOSIUM ON SOIL EROSION AND SEDIMENTATION BY WATER,
American Society of Agricultural Engineers
American Society of Agricultural Engineers, 2950 Niles Road, Saint Joseph,
Michigan 49085.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, 151 p, December 12-13, 1977, 25 fig, 17 tab,
275 ref, 37 equ.
Descriptors: Soil erosion, Erosion, Sedimentation, Erosion control. Erosion rates,
Sediment control, Sediment discharge, Sediment load, Sediment transport, Sedimen-
tation, Sediments.
The results of numerous research projects and investigations are presented which
focus upon defining appropriate technologies for alleviating soil erosion and
sedimentation by water. Each year, 1 million acre-feet of sediment, the product
of erosion, is deposited in reservoirs, occupying waters-storage volume that cost
100 million dollars to develop. Additionally, sediment from construction clogs
drainage ditches and storm sewers. Sediment from surface mines damages adjacent
waterways, destroying aquatic life. Sediment from irrigated fields increases
the turbidity of nearby streams and makes treatment for municipal uses difficult.
Although agricultural erosion and sedimentation problems have received wide-
spread attention for decades, the problem still persists. Methods to control
erosion in 1940 are seldom acceptable in 1977, Massive changes in farm machinery,
animal husbandry, and cropping have negated many methods of erosion control. New
vegetative and mechanical methods for erosion control have been developed to
solve problems in 1977. In recent years, besides experiencing an increased de-
mand for clean water, there has been an increasing demand for new construction
and for minerals and new sources of fossil fuels. Technology has been developed
to control erosion and sedimentation from surface mines and construction sites.
77:02J-013
SEDIMENT PREDICTION IN THE EASTERN UNITED STATES,
Malcolm, H.R., Jr., and Smallwood, C.r Jr.
North Carolina State University, Department of Civil Engineering, Raleigh, North
Carolina.
Journal of the Water Resources Planning and Management Division, American Society
of Civil Engineers, Vol. 103, No, WR2, Proceedings Paper 13340, p 285^298, November
1977. 6 fig, 2 tab, 13 ref, 2 append.
Descriptors: *Sedimentation, *Streams, *Lakes, *Model studies, Mathematical
models, Equations, Urbanization, Drainage, Erosion, Forecasting, Planning, Channels,
Lake sediments, Deposition (.sediments), Sediment discharge. Sediment transport,
Watersheds (basins), Erosion, Sedimentology.
103
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Sediment discharge equations were derived for wooded, rural, urban, and severely
exposed watersheds on the East Coast. The equations were used to model the im-
pact of urbanization on sedimentation activity. The equations can be used in
crude, but reasonably effective, modeling techniques to study some impacts of
urbanization on streams and lakes. The equations confirmed and quantified the
existence of a two-part urban sedimentation problem: one associated with erosion
of denuded areas, and the other with the degradation of stream channels rendered
unstable by extensive watershed changes. Two studies compared results with
historical cases.
77:02J-014
RESOURCE ADEQUACY IN LIMITING SUSPENDED SEDIMENT DISCHARGES FROM AGRICULTURE,
Heady, E.O., and Meister, A.D.
Iowa State University, Center for Agricultural and Rural Development, Ames,
Iowa 50011.
Journal of Soil and Water Conservation, Vol. 32, No, 6, p 289-293, November-
December, 1977. 3 fig, 6 tab, 3 ref.
Descriptors: Computer programs, Model studies, Pollution, Agriculture, Water
surface, Irrigation, Erosion, Sediments, Suspended sediments.
The Iowa State University national programming model was used to evaluate the
economic impacts of controlling nonpoint pollution from agriculture and to assess
whether environmental improvement goals could be met in conjunction with high
agricultural exports. Alternatives analyzed included a base solution, high
exports, land and water conservation, and environmental enhancement. High ex-
ports could be attained simultaneously under the land and water conservation al-
ternative. Exports must be reduced, however, under the environmental enhance^
ment alternative. To meet exports under the land and water conservation alter-
native, 10 million acres of wetlands would need to be converted to cropland.
Returns to land would increase considerably under all alternatives other than
the base solution. There would be wide variations among regions, however. In
general, a relative redistribution of income from irrigated to drylands and
from erosive to nonerosive farming regions would occur.
77:02J-015
FILTRATION OF NONHOMOGENEOUS SEDIMENT BY SIMULATED VEGETATION,
Hayes, J.C., and Barfield, B.J.
Kentucky University, Department of Agricultural Engineering, Lexington, Kentucky,
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1^18,
7 fig, 2 tab, 14 ref, 24 equ.
Descriptors: Model studies, Sediment, Sedimentation, Sediment loads, Open channels,
Simulation analysis, Hydrographs, Vegetation, Vegetation effects.
A nonsteady state model is presented for determining the sediment infiltration
of an artificial grass filter under varying flow rates, sediment loads, particle
sizes, channel slopes, and media density. Good agreement was found between
predicted and observed profiles for given flow conditions and inflow hydrographs
using laboratory data.
77:02J-016
SOIL LOSS EQUATION: DERIVATION FOR STEEP SLOPES,
Gregory, J.M., Johnson, H.P., and Kirkham, D.
Missouri University, Department of Agricultural Engineering, Columbia, Missouri,
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p l<-29,
4 fig, 1 tab, 10 ref, 65 equ.
Descriptors: Model studies, Simulation analysis, Sediment transport, Erosion,
Soil erosion.
An equation has been derived for the prediction of soil loss from areas with
steep slopes. The equation compares favorably with the Universal Soil Loss
Equation for flat slopes (0-20 percent) and agrees with experimental results in
the literature for steep slopes (20-100 percent).
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77:02J-017
PREDICTING SEDIMENT YIELD FROM AGRICULTURAL LAND,
Shelton, C.H.
Tennessee University, Department of Agricultural Engineering, Knoxville,
Tennessee.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, pi-16.
4 fig, 3 tab, 6 ref, 3 equ.
Descriptors: Sediments, Sediment yield, Agriculture, Simulation analysis.
Runoff, Soil erosion.
Three forms of sediment-yield prediction equations were developed and tested
with data from 105 runoff events on five watersheds. Runoff volume accounted
for variations in yield better than maximum 30-minute intensity rainfall, ero-
sive-potential rainfall factor, or peak runoff rate; and the best prediction
equation was obtained after logarithmic transformation of variables.
77:02J-018
WATER QUALITY LOADINGS DURING THIRTEEN STORMS ON THE CADDO RIVER, ARKANSAS,
Perrier, E.R., Westerdahl, H.E., and Nix, J.F.
United States Army Engineer District, Waterways Experiment Station, Environmental
Effects Laboratory, Vicksburg, Mississippi.
American Society of Agricultural Engineers, Post Office Box 410, Saint Joseph,
Michigan 49085, p 1-28. 5 fig, 11 tab, 14 ref.
Descriptors: Water quality, Sediments, Sedimentation, Sediment loads, Sedimen-
tary basins, Arkansas.
Nonpoint source loadings of twenty-five selected water quality parameters have
been described for thirteen storm events on the Caddo River drainage basin in
Arkansas. These parameters were functionally related to on-^site measurements
although wide variation was attributable to hysteresis and the stochastic nature
of the system.
77:02J-019
PREDICTION OF SEDIMENT BASIN PERFORMANCE,
Ward, A.D., Haan, C.T., and Barfield, B.J.
Kentucky University, Department of Agricultural Engineering, Lexington, Kentucky.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1^29,
11 fig, 2 tab, 17 ref, 12 equ, 1 append.
Descriptors: Model studies, Mathematical analysis, Simulation analysis, Sedimen-
tation, Sediment control, Sediment load.
A mathematical model for simulating the sedimentation characteristics of detention
basins is described. Using data generated by the model, the significant factors
affecting basin trapping efficiency and peak sediment outflow concentrations are
identified. Equations for predicting these factors are developed,
77:02J-020
THE ANSWERS MODEL: A PLANNING TOOL FOR WATERSHED RESEARCH,
Beasley, D.B., Monke, E.J., and Huggins, L.F.
Arkansas University, Department of Agricultural Engineering, Fayetteville, Arkansas.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-21,
12 fig, 2 tab, 15 ref, 7 equ.
Descriptors: Model studies, Computer programs, Hydrology, Erosion, Soil erosion.
The ANSWERS model, a distributed parameter watershed hydrology and erosion simulator,
is presented. The basic concepts and the pertinent component relationships are
described. In addition, sample outputs from the ANSWERS model are included.
105
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77:02J-021
ERODIBILITY OF SELECTED CLAY SUBSOILS IN RELATION .TO PHYSICAL AND CHEMICAL
PROPERTIES,
Romkens, M.J.M., Roth, C.B., and Nelson, D,W.
Agricultural Research Service, Sedimentation Laboratory, Oxford, Mississippi,
Soil Science Society of America Journal, Vol. 41, No. 5,. p 954-960, September-
October, 1977. 2 fig, 6 tab, 21 ref.
(See 77:02G-174)
77:02J-022
SOLVING THE SOIL EROSION PROBLEM,
Barlow, T.
Natural Resources Defense Council, Incorporated, 917 15th Street, N.W,, Washington,
D.C. 20005.
Journal of Soil and Water Conservation, Vol. 32, No. 4, p 147-149, July-August,
1977.
Descriptors: Erosion, Soil erosion, Water quality, Water pollution, Runoff.
Soil erosion is a serious national problem today. Air and water can be cleansed
of pollutants, but when the topsoil is gone, the country is in real trouble. How
serious is the erosion problem? Let me cite some reports and hearings from the
past two years. And please note, these are not wild-eyed radicals speaking. They
are agricultural scientists and farmers who work the land, the people who know
best.
77:02J-023
EVALUATION OF WILD OAT STRAW AS A SOIL EROSION RETARDANT USING SIMULATED RAINFALL,
Singer, M.J., and Blackard, J.
California University, Department of Land, Air and Water Resources, Davis,
California.
Agronomy Journal, Vol. 69, No. 5, p 811-814, September-October, 1977. 3 fig,
2 tab, 13 ref.
Descriptors: Erosion, Soil erosion, Rainfall, Oats, Runoff, Mulches.
Soil cover is recognized as an important factor in soil erosion control. This
study was made to determine the quantitative relationship between cover percent
for one cover type and soil loss under simulated rainfall. Data from this ex-
periment are used to calculate a cover coefficient for wild oat straw similar to
the "C" factor in the Wischmeier Universal Soil Loss Equation. The R, K, L, S,
and P factors were kept constant during the experiments, A rainfall simulator
was used in the laboratory to produce 30 min rainfall events of 76 mm/hour (3 in/
hour) intensity on soil material at 9% slope. Under these conditions, wild oat
straw significantly reduced sediment loss at cover levels of 50% or more. A
significant reduction in runoff volume was observed for cover percentages ex-
ceeding 90%.
77:02J-024
INFLUENCE OF ENVIRONMENTAL PARAMETERS ON EDTA BIODEGRADATI0N IN SOILS AND SEDIMENTS,
Tiedje, J.M.
Michigan State University, East Lansing, Michigan 48824,
Journal of Environmental Quality, Vol. 6, No. 1, p 21-26, January-March, 1977,
4 fig, 3 tab, 20 ref.
Descriptors: Soils, Soil investigations, Soil texture, Sediments, Sedimentation,
Chelation.
14C-EDTA (.ethylenediaminetraacetate) was slowly degraded to 14CO2 by all soils
tested from the major agricultural EDTA use areas; by soils varying in uses,, pH,
and texture; and by sediments from the Detroit River. EDTA degradation appears
to be a result of cometabolism by established microbial populations. Production
of 14CO2 from EDTA occurred under aerobic but not anaerobic conditions. No detect-
able quantities of intermediates accumulated under either condition, EDTA deg-
radation followed first order kinetics for concentrations ranging from 0.4 to
90 ppm. Degradation was observed up to 1,000 ppm EDTA, the highest concentration
106
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tested. The date of sample collection had a marked effect on extent of degrada-
tion with the winter-collected samples showing greater than twice the degradation
of summer-collected samples. The Q10 was two up to 30C. Initially degradation
of 50C was limited, but after 9 weeks incubation the rate accelerated indicating
the adaptation of thermo-tolerant EDTA-degrading populations. The extent of
degradation among soils was variable; common values for 2 to 4 ppm of added
14C-EDTA mineralized were 13 to 45% after 15 weeks and 65 to 70% after 45 weeks.
77:02J-025
SOIL EROSION AND SEDIMENTATION BY WATERAN OVERVIEW,
Foster, G.R., and Meyer, L.D.
Purdue University, Department of Agricultural Engineering, West Lafayette, Indiana.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 1-13, December 12-13, 1977. 53 ref.
Descriptors: Soil erosion, Erosion, Sediments, Rainfall, Water quality, Sediment
load, Sediment transport.
Soil erosion and sedimentation by water primarily involve the processes of de-
tachment, transportation, and deposition of sediment by raindrop impact and
flowing water. Erosion and sedimentation are major problems that reduce the
productivity of cropland, degrade water quality, carry polluting chemicals, and
reduce the capacity of water conveyance structures. The erosions-sedimentation
system is composed of upland and channel components, While the uplands act some-
what independently of the channels, the behavior of the channels is directly in<-
fluenced by the upland inputs. Spatial and temporal variations in erosion are
common with time lags in sediment yield as great as several decades. Climate,
soil, topography, and land use are major factors influencing erosion and
sedimentation.
77:02J-026
CURRENT SOIL EROSION AND SEDIMENT CONTROL TECHNOLOGY FOR RURAL AND URBAN LANDS,
Highfill, R.E., and Kimberlin, L.W.
United States Department of Agriculture, Soil Conservation Service, Washington,
D.C.,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 14-22, December 12-13, 1977, 28 ref,
Descriptors: Erosion, Sediments, Water quality, Water resources, Agriculture,
Erosion control, Sediment load.
Erosion and sedimentation are important factors in managing land and water re-
sources. Agricultural land, especially cropland, produces the largest amount
of sediment annually. The next largest source is geologic erosion. Range and
forest lands and construction activities are about equal in the amount of sedi-
ment produced. Erosion control is important to maintain productivity on'
agricultural and forest lands and to aid in sediment pollution control. Pro*-
cedures have been developed for predicting erosion and sediment yield. Technology
is available to reduce the amount of erosion and sediment induced by water from
most land areas. In some places, additional research or data are needed to im<-
prove the performance of erosion control systems or reduce the cost, or both.
The quality of installation and maintenance of erosion control measures is still
one of the major problem areas.
77:02J-027
POLITICAL, SOCIAL, AND ECONOMIC ASPECTS OF SOIL EROSION AND SEDIMENTATION
CONTROL PROGRAMS,
Heft, F.E.
Ohio State University, Department of Agronomy, Ohio,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 23-30, December 12-13, 1977,
Descriptors: Economics, Erosion, Sediments, Soil erosion, Political aspects,
Social aspects, Social values.
107
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Recently, we have witnessed a sincere, dedicated, and sometimes fervent concern by
our citizenry for our natural resource-use and management policies. The most ob-
vious of these concerns are couched in our environmental spectrum containing both
realistic and unrealistic demands upon our political, social, and economic systems.
Shrinking supplies of certain natural resources and the ability of our nation to
retain a high degree of self-sufficiency has brought serious challenges to our
management policies.
77:02J-02S
PREDICTING SOIL EROSION,
Kimberlin, L.W., and Moldenhauer, W,C.
United States Department of Agriculture, Soil Conservation Service, Washington,
D.C. ,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 31-42, December 12-13, 1977. 26 ref.
Descriptors: Soil erosion, Erosion, Erosion rates, Sediment transport, Sedimenta-
tion.
Erosion of soil by water poses an increasing threat as needs for food and fiber
production and space for social and economic necessities of a growing population
and pressures to our Nation's land resources. The Universal Soil Loss Equation
(USLE) developed through many years of cooperative efforts of the Agricultural
Research Service, state experiment stations, and the Soil Conservation Service
is a highly useful tool for predicting sheet and rill erosion under various con-
ditions of land use and management. It is widely accepted and used by soil
conservationists and others. However, there are some problems associated with
its use and some additional needs to supplement its use in the field,
77:O2J-029
PREDICTING SEDIMENT YIELDS,
Onstad, C.A,, Mutchler, C.K., and Bowie, A.J,
United States Department of Agriculture, Agricultural Engineering Division,
Morris, Minnesota.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 43-58, December 12-13, 1977. 50 ref, 14 equ.
Descriptors: Soil erosion, Erosion, Sediments, Sediment transport, Sediment load,
Sediment discharge, Model studies.
Sediment yield is the amount of soil transported from a drainage basin. Studies
for predictions of sediment yield have general uses, which include the following.
Simulations are used to extend a short-term sampling program to an adequate data
base to predict future watershed response to various land^use alternatives and
as an ordered sequence of steps in time and space so that information gaps can be
identified. The specific needs for sediment yield prediction are so varied that
no single model could meet them without a great loss o£ efficiency. These needs
generally fall into the categories of length of model event time, area to be
simulated, and sediment sources. At present, many sediment yield models are
available for use or have been used for various purposes,
77:02J-030
ESTABLISHING SOIL LOSS AND SEDIMENT YIELD LIMITS FOR AGRICULTURAL LAND,
Logan, T.J.
Ohio State University, Ohio Research and Development Center, Department of
Agronomy, Ohio.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 59-68, December 12-13, 1977, 1 fig, 3 tab,
13 ref, 3 equ.
Descriptors: Agriculture, Soil erosion, Erosion, Sedimentation, Sediment dis-
charge, Sediments, Sediment load.
108
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Soil loss tolerance values, T-values, are currently based on annual gross .erosion
rates that can be tolerated and still maintain crop productivity. The major
criterion used by Soil Conservation Service in establishing these values which
range from 1 to 5 tons acre (-1) year (-1) is topsoil depth. The assumptions on
which this criterion is based are reviewed. Soil loss in relation to sediment
and nutrient watershed yields is discussed and criteria which might be used to
establish tolerance values for sediment and nutrient loss abatement programs are
given. Soil loss tolerances for sediment and nutrient loss reduction will likely
be more restrictive than T-values and should be applied only to critical areas
where the impact of these sources is greatest.
77:02J-031
SEDIMENTATION AND EROSION CONTROL IMPLICATIONS FOR WATER QUALITY MANAGEMENT,
Mulkey, L.A., and Falco, J.W,
United States Environmental Protection Agency, Technology Development and Applica-
tions Branch, Environmental Research Laboratory, Athens, Georgia,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 69-90, December 12-13, 1977. 11 fig, 4 tab,
34 ref, 20 equ.
Descriptors: Soil erosion, Erosion control, Water quality, Sediment transport,
Simulation analysis.
Erosion and sedimentation, including sediment transport through a watershed sys-
tem, play important but complex roles in water quality management. The most
meaningful way to evaluate the relative effectiveness of various erosion control
methods for water quality management is via continuous simulation models. If
water quality goal attainment is attempted by application of source controls
within some specified technology limits (including costs), however, a more sim-
plistic approach may be used for analysis of this nonpoint source of environmen-
tal pollution. This paper focuses on the latter technique, but also presents
the results of more sophisticated analysis methods for illustrative purposes.
77:02J-032
VEGETATIVE WATER EROSION CONTROL FOR AGRICULTURAL AREAS,
Mannering, J.V,, and Fenster, C.R.
Purdue University, Department of Agronomy, Indiana,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 91-106, December 12-13, 1977, 3 fig, 11 tab,
27 ref.
Descriptors: Soil erosion, Erosion control, Sediment transport, Vegetation,
Vegetation effects.
Methods whereby vegetation can effectively control water erosion are presented.
Both crop residues and their management as well as growing vegetation are con?-
sidered. Crop residue factors that determine their erosion control effective-
ness includes (a) the type of crop, Cb) the amount and type of residues pro*-
duced, (c) whether or not residues are removed or left on the field and (d)
the effect of residue placement by tillage systems,
77:02J-033
MECHANICAL EROSION CONTROL FOR AGRICULTURAL AREAS,
Jeschke, J.L., Moe, R.C., and Carmack, W.J.
United States Department of Agriculture, Soil Conservation Service, Lincoln,
Illinois.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 107-115, December 12-13, 1977, 2 fig, 4 tab,
5 ref.
Descriptors: Soil erosion, Erosion, Erosion control, Agriculture, Terracing,
109
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Mechanical erosion control is discussed as it relates to practice application on
sloping cropland. Planning and design considerations for applying terraces,
grade stabilization structures, and debris basins are presented. Special empha-
sis is placed on the problems involved in designing these practices to be compati-
ble with current farming techniques. The benefits of using topographic maps pro-
duced by aerial surveys in planning and design of these practices are also dis-
cussed.
77:02J-034
PROBLEMS OF IMPLEMENTING EROSION CONTROL,
Hagen, W.R.
State Soil Conservation Committee, Waterville, Iowa 52170,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 116-124, December 12-13, 1977. 2 tab.
Descriptors: Soil erosion, Erosion, Erosion control, Sediment transport, Soil
conservation.
The author cites personal involvement in soil and water conservation work on his
own farm, during the formation years of the soil conservation movement in the
United States to the present. Personal experiences in problems of implementing
erosion control are shown, as well as progress in spite of those problems. Cur-
rent problems in erosion control include (.1) only partial community acceptance,
(2) peer group pressure, (3) unsuitable equipment, (.4) resistance to change,
(5) economic burdens, and (.6) damaging press coverage. To counteract these ob-
stacles, the author suggests (.1) continued use of accurate news releases, (.2)
continued education on natural resource problems, (.3) election and appointment
of public officials with a knowledge of and concern for natural resources, (4)
passage of land use legislation, (.5) imposing fines on blatant abusers of the
land, (6) giving tax incentives to landowners who practice conservation and (7)
increasing government cost-sharing for establishment of permanent soil conserva-
tion practices,
77:02J-035
EROSION AND SEDIMENT CONTROL IN URBANIZING AREAS,
Boysen, S.M.
United States Department of Agriculture, Soil Conservation Servicef College
Park, Maryland 20740.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 125-136, December 12-13, 1977, 7 fig, 8 ref,
Descriptors: Soil erosion, Erosion, Erosion control, Sediment control,. Sediments,
Urbanization.
The urban sediment control program in Maryland according to a recent United States
Geological Survey report has caused a 60 to 80 percent reduction in construction
site sediment yields between 1966 and 1974, The sediment control program, based
on a set of basic principles, was developed and implemented beginning in Mont-
gomery County in 1965. Technical principles for controlling erosion and sediment
were also developed. The present state law requires that all development must
have a sediment control plan approved by the soil conservation district before
any construction begins.
77:02J-036
EROSION AND SEDIMENT CONTROL FOR COAL SURFACE MINE AREAS,
McCarthy, R.E.
Washington Irrigation and Development Company, Centralia, Washington 98531,
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 137-145, December 12-13, 1977, 1 fig, 1 tab,
Descriptors: Mining, Water quality, Drainage, Erosion, Soil erosion, Erosion
control, Sediments, Sediment control,
The elimination of the impact of a major coal surface mine on the water quality of
adjacent waterways through the use of drainage systems, settling ponds, and a mon-
itoring system for dispensing polymer electrolytes for chemical flocculation of
suspended sediment is described.
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77:02J-037
EROSION AND SEDIMENTATION ON IRRIGATED LANDS,
Bondurant, J.A.
Agricultural Research Service, Snake River Conservation Research Center, Kimberly
Idaho 83341.
Proceedings of the National Symposium on Soil Erosion and Sedimentation by Water,
Palmer House, Chicago, Illinois, p 146-151, December 12-13, 1977, 13 ref.
Descriptors: Erosion, Soil erosion. Irrigation, Surface irrigation, Sediments,
Sediment discharge.
Most erosion on irrigated land is caused by the irrigation itself. Surface ir<-
rigationwhere water is applied directly to the surface as in furrow or border
irrigationcan be very erosive. Data from southern Idaho show that large
quantities of sediment may be generated within an irrigation system; however,
less sediment may be returned to the river than is diverted with the water
supply. Technology for reducing erosion from irrigated fields is available!
irrigation systems may be modified or changed, fields may be leveled or pro^
filed to nonerosive slopes, tillage operations can be reduced, vegetative filter
strips and drain ditch elevation control will remove sediment, or sediment ponds
may be used after runoff leaves the field.
77:02J-038
AN EROSION MODEL FOR ARID WILDLAND WATERSHEDS,
Wagenet, R.J., Grenney, W.J., and Jurinak, J.J.
Utah State University, Department of Soil Science, Logan, Utah.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-22.
6 fig, 2 tab, 6 ref.
Descriptors: Computer programs, Model studies, Erosion, Soil erosion, Sediments,
Heavy metals.
A nonsite specific computer model was developed to predict environmental metal
distribution resulting from the erosion of stack derived emissions of a coal
fired electric generating facility. Model predictions of sediment eroded Znf
Cd, Cr, Pb, and Hg are presented for a 25 year period, and show Hg and Cd to be
of environmental concern while indigenous soil levels of Zn, Cr, and Pb greatly
outweigh contributions expected from the generating facility.
77:02J-039
PREDICTION OF SEDIMENT TRANSPORT IN A GRASSED MEDIA,
Barfield, B.J., Tollner, E.W., and Hayes, J.C.
Kentucky University, Department of Agricultural Engineering, Lexington, Kentucky
40506.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, North Carolina State University, Raleigh, North
Carolina, p 1-23. 7 fig, 3 tab, 13 ref, 2Q equ.
Descriptors: Model studies, Sediments, Sediment control, Sediment loads, Sediment
transport, Vegetation, Vegetation effects.
A steady state model is presented for determining the sediment filtration capacity
of a grass media under varying flow rates, sediment loads, particle sizes, flow
durations, channel slopes, and media density. It is possible to use the model_
to predict the required media spacing, channel slope, and length of media to give
a desired outflow concentration for given flow conditions,
77:02J-040
COMPARATIVE ERODIBILITY OF LOESS SOILS IN POLAND AND THE UNITED STATES,
Piest, R.F., and Ziemnicki, S.
United States Department of Agriculture, Agricultural Research Service, Watershed
Research Unit, Columbia, Missouri.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-29.
7 fig, 3 tab, 17 ref, 2 equ.
Ill
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Descriptors: Erosion, Soil erosion, Iowa, Sediment transport, Erosion control,
Erosion rates.
Historic erosion patterns between loess soil regions of Poland and southwestern
Iowa were compared. A rational interpretation of the measured soil losses re-
ported by various researchers was attempted through application of the Universal
Soil Loss Equation. Gullying rates and causes in both countries were examined,
77:02J-041
A RUNOFF EROSIVITY FACTOR AND VARIABLE SLOPE LENGTH EXPONENTS FOR SOIL LOSS
ESTIMATES,
Foster, G.R., Meyer, L.D., and Onstad, C,A.
Purdue University, Department of Agricultural Engineering, Lafayette, Indiana,
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 4,
p 683-687, July-August, 1977. 1 tab, 15 ref.
Descriptors: *Soil erosion, *Sediment yield, *Watersheds (basins), *Mathematical
models, Equations, Erosion, Sheet erosion, Rill erosion, Runoff, Estimating,
On-site tests, Slopes, Analysis.
A runoff erosivity term was developed for the Universal Soil Loss Equation (USLE)
from analysis of an erosion equation derived from basic erosion principles, The
accuracy of erosion estimates for individual storms can be improved significantly
by using a soil loss equation having separate terms for rill and interrill ero-
sion. Also, such an equation can be used to estimate the amount of sediment from
different slope segments and also the amount from the soil surface and from deeper
within the soil profile. The analyses showed the potential of estimating soil
loss using separate rill erosion and interrill erosion terms in an erosion equa-
tion. Research is needed to define precisely the relationship between rill
erosion and runoff erosivity and that between interrill erosion and rainfall
erosivity- The separate effects of cover, management, and supporting practices
on rill and interrill erosion need to be established. The achievement of the
mentioned goals promises to provide a flexible, useful, and accurate erosion equa-
tion based on sound erosion principles. In the meantime, basic erosion principles
can be used as guidelines to adjust parameters in the USLE for more accurate soil
loss estimates for specific time periods and situations,
77:02J-042
AN EROSION EQUATION DERIVED FROM BASIC EROSION PRINCIPLES,
Foster, G.R., Meyer, L.D,, and Onstad, C,A,
Purdue University, Department of Agricultural Engineering, Lafayette, Indiana,
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 4,
p 678-682, July-August, 1977. 28 ref.
Descriptors: *Soil erosion, *Watersheds (.basins), *Theoretical analysis, *Mathe-
matical models, Rill erosion, Sediment transport, Sediment yield, Sheet erosion,
Erosion, Equations, Overland flow, Runoff, Rainfall, Erosion control, Land
management, Shear stress.
An erosion equation was derived from the continpity equation for sediment trans-
port and other basic equations describing rill and interrill erosion. The re-
sulting equation is a useful model for explaining the behavior of the erosion
process. The equation might serve as the basis for an operational equation for
estimating soil loss for specific storms.
77:02J-043
EROSION OF THE TARKIO DRAINAGE SYSTEM, 1845-1976,
Piest, R.F., Elliott, L.S., and Spomer, R.G,
Agricultural Research Service, Columbia, Missouri.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 3,
p 485-488, May-June, 1977. 3 fig, 2 tab, 4 ref.
112
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Descriptors: *Streara erosion, *Channel erosion, *Rivers, *Iowa, *Missouri,
Runoff, Drainage, Soils, Soil texture, Loess, Degradation (slope), Degradation
(stream), Scour, Cultivated lands, Agriculture, Gullies, Geomorphology, Slopes,
Erosion, History.
Historic and geologic evidence indicated that channel and gully erosion was nearly
nonexistent when the loess-mantled Tarkio Basin of southwestern Iowa and north
western Missouri was settled about 1845. The pattern of channel development-
gleaned from old land surveys, records from drainage districts, highway bridge
surveys, and other documents-is related to the intensity of agriculture ana is
linked complexly to the general runoff regimen and to changes in soil water
content along channel boundaries. Some channel enlargement during the post-
settlement period, 1845-1976, is quantified. Channel profile changes during
recent years, 1939-1976, were reconstructed. The excessive scour in a channel
reach of West Tarkio Creek was explained tentatively on the basis of geomorphic
principles and differences in substrata erodibility.
77:02J-044
RUNOFF, EROSION, AND NUTRIENT MOVEMENT FROM INTERRILL AREAS,
Monke, E.J., Marelli, H.J., Meyer, L.D., and DeJong, J.F.
Purdue University, Department of Agricultural Engineering, Lafayette, Indiana.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 1,
p 58-61, January-February, 1977. 4 fig, 6 tab, 9 ref.
Descriptors: *Runoff, *Erosion, *Nutrients, *0verland flow, *Rainfall, Laboratory
tests, Simulated rainfall, Precipitation (atmospheric), Soil erosion, Suspended
solids, Nitrogen, Phosphorus, Inflow, Soils, Loam, Silts, Sediments, Agriculture.
The influence of rainfall and overland flow on interrill erosion and associated
nutrient losses was studied for flatland conditions. Interrill erosion rates
were substantially large. However, amounts of eroded soil reaching actual stream
systems may be greatly reduced, depending on the severity of storms. Interrill
erosion rates can be decreased substantially by improved tilth. In soils with
excellent tilth, the silt fraction in the eroded soil was higher than in the
original soil, and the clay and sand fractions were lower. Although N and P con-
centrations in the soils with excellent tilth were quite high, losses of these
nutrients in sediment runoff were low because of increased infiltration.
77:02J-045
AN ECONOMIC EVALUATION OF CROPLAND USE AS A CONTROL FOR SEDIMENT NONPOINT POLLUTION,
Wade, J.C., and Heady, E.0,
Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa,
Agriculture and Environment, Vol. 3, No. 4, p 307-323, October 1977. 6 fig, 3 tab,
12 ref, 11 equ.
Descriptors: Sediments, Sedimentation, Economics, Model studies, Water quality,
Agriculture, Pollution.
Substantial economic change occurs if national goals of sediment control are
established. An environmental/economic model of national agricultural production
and sedimentwater quality analyses five alternative goals of sediment control
to give insight into changes in farm production technologies, incomes, pollution
levels, and consumer and producer costs in the 48 contiguous United States,
77:02J-046
NITROGEN AND PHOSPHORUS MOVEMENT FROM AGRICULTURAL WATERSHEDS,
Burwell, R.E., Schuman, G.E., Heinemann, H.G., and Spomer, R.G.
United States Department of Agriculture, Department of Soil Science, Agricultural
Research Service, Columbia, Missouri 65201,
Journal of Soil and Water Conservation, Vol. 32, No. 5, p 226-230, September-
October, 1977. 6 tab, 13 ref.
Descriptors: Nitrogen, Phosphorus, Nutrients, Fertilizers, Fertilization, Water-
sheds (basins), Iowa, Runoff, Erosion, Soil erosion.
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A five-year study on Missouri Valley deep loess watersheds near Treynor, Iowa,
to characterize the movement of nitrogen (N) and phosphorus (P) as influenced
by applied fertilizer and conservation practices was conducted. Our report pre-
sents watershed budget-accounting information for measured N and P movement that
included (a) corn crop use, (b) surface runoff losses, (c) deep percolation,
and (d) subsurface discharge. Erosion control and the application of N and P
fertilizer at rates recommended for annual crop use minimized losses of these
nutrients from the watersheds.
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SECTION IX
WATER CYCLE
CHEMICAL PROCESSES (GROUP 02K)
77:02K-001
ION ACTIVITY PRODUCTS OF CALCIUM CARBONATE IN WATERS BELOW THE ROOT ZONE,
Suarez, D.L.
Agricultural Research Service, Salinity Laboratory, Riverside, California,
Soil Science of America Journal, Vol. 41, No. 2, p 310-315, March-April, 1977.
4 fig, 3 tab, 27 ref.
Descriptors: *Ions, *Soil water, *Calcium carbonate, *Arizona, *Calcareous
soils, Calcite, Soil chemistry, Irrigation wells, Irrigation water, On-site
investigations, Chemical precipitation,
A study was conducted to determine the pH, Ca(2+) and HC03C-) relations in 28
well waters obtained from beneath fields in the Wellton-Mohawk Irrigation
District of Arizona. Based on field measurements of pH, the mean CaC03 ion
activity product (IAP) was 11.3 x 10 to the minus 9th power (pIAP 7.95) with a
standard error of 0.7 x 10 to the minus 9th power at field water temperatures
of about 25C. The residence time of waters in the soil varies widely; results
indicate a longer residence time is associated with greater ionic strength. The
lack of a trend in pIAP vs. ionic strength indicates the kinetics of calcite
equilibration (from super-saturation) is slow in soil-water systems. Further
support for this was an average pIAP of 7.97 calculated from 35 water analyses
obtained from wells in the Grand Valley of Colorado and by a pIAP value of 7.96
in a soil water sample from a lysimeter study. A pIAP value of 7.95 is sug-
gested for use in predictive models when CaC03 precipitation occurs. Waters
experiencing rapid CO2 degassing (for example, surface exposure of drainage
waters) would have higher IAP values and measurable rates of precipitation.
77:02K-002
DISSOLUTION KINETICS OF CARBONATE ROCKS I. EFFECTS OF LITHOLOGY ON DISSOLUTION
RATE,
Rauch, H.W., and White, W.B.
West Virginia University, Department of Geology and Geography, Morgantown, West
Virginia.
Water Resources Research, Vol. 13, No. 2, p 381-394, April 1977. 15 fig, 4 tab,
36 ref.
Descriptors: *Carbonate rocks, *Solubility, laboratory tests, *Pennsylvania,.
Dolomite, Calcite, Limestones, Karst, Sedimentary rocks, Caves, Geomorphology,
Rock properties, Rocks, Carbon dioxide. Water, Chemistry, Hydrogen ion concen-
tration, Karst hydrology, Groundwater, Petrology,
Laboratory dissolution of Middle Ordovician rock samples from central Pennsylvania
was studied at 23C and 1 atm carbon dioxide pressure. Carbonate dissolution rates
were compared at 22% bicarbonate saturation with respect to both calcite and dolo-
mite. The results showed that carbonate lithology exerts a strong influence on
the dissolution rate and hence, on the degree of cavity development in karst
aquifers. The dissolution rate is affected most significantly by dolomite and
impurity content. The rate decreases as percentages of dolomite and disseminated
insolubles increase. Maximum dissolution rates occur for carbonate rocks with
1.0-2.5% MgO content and with abundant silty streaks. The sparite content is
related inversely to cave development but is independent of dissolution rates
measured under the laboratory conditions adopted in this study.
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77 :02K-003
ESTIMATED ASSOCIATION CONSTANTS FOR SOME COMPLEXES OF TRACE METALS WITH INORGANIC
LIGANDS,
Mattigod, S.V., and Sposito, G.
California University, Department of Soil and Environmental Science, Riverside,
California 92521.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1092-1097, November-
December, 1977. 3 fig, 3 tab, 60 ref, 9 equ.
Descriptors: Soils, Soil investigations, Model studies, Heavy metals, Soil
chemistry.
Chemical equilibrium studies of trace rnetals in soils by an ion-association model
require reliable data on thermodynamic association constants for various metal-
ligand complexes. Therefore, available experimental data at 25 C were compiled
for complexes of the transition metal cations Mn2+, Fe2+, Ni2+, Cu2+, and Zn2+
with the ligands C03(2-), HCo3(-), S04(2-), HS04(-), P04(3-), HP04 (2-), H2P04(-),
Cl(-), and OH(-). However, experimental values of the thermodynamic association
constants for many of the complexes were not available. This lack of information
was alleviated by employing the theoretical model of Kester and Pykowicz and the
semiempirical models of Nieboer and McBryde, and Van Panthaleon Van Eck to make
estimates of the as yet unmeasured association constants. These estimated con-
stants were tabulated in a compact form along with the experimental values. This
compilation of 100 association constants, although provisional, should prove help-
ful in a variety of studies on trace metal equilibria in soils until more reliable
experimental data become available.
77:O2K-004
SULFURIC ACID AS AN AMENDMENT FOR RECLAIMING SOILS HIGH IN BORON,
Prather, R.J.
United States Salinity Laboratory, Post Office Box 672, Riverside, California
92502.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1098-1101, November-
December, 1977. 1 fig, 3 tab, 29 ref.
(See 77:026-154)
77:02K-005
NITRATE IN EFFLUENTS FROM IRRIGATED LANDS (ANNUAL REPORT),
Pratt, P.F., Biggar, J.W., Broadbent, F.E., et al,
Research Applied to National Needs, National Science Foundation, Washington,
D.C. 20550.
Publication No. PB-275 673, July 1977, 91 p, 13 fig, 17 tab, 14 ref.
Descriptors: Nitrates, Nitrification, Chemical reactions, Denitrification,
Irrigated land, Effluents, Irrigation, Nitrogen, Soil-water-plant relationships,
Soil properties.
This report presents progress in the development of technologies for measurements
of NO(-)3 leaching and denitrification and in our understanding of the factors
that influence the quantities of nitrogen that go into various sinks. Research
on various aspects of the nitrogen cycle in the soil-plant-water system are dis-
cussed, including: (1) nitrogen transformations with particular emphasis on
denitrification; (.2) crop utilization of nitrogen; (3) incorporation of nitrogen
into and cycling in soil organic matter; (4) fluxes of water through the root
zone; and (5) effects of soil profile properties on nitrogen leaching and denitri-
fication.
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SECTION X
WATER CYCLE
ESTUARIES (GROUP 02L)
77:02L-001
CROP TEMPERATURE REVEALS STRESS,
Jackson, R.D., Idso, S.B., Reginato, R.J,, Ehrler, W.L.
Agricultural Research Service, Water Conservation Laboratory, Phoenix, Arizona,
Crops and Soils, Vol. 29, No. 8, p 10-13, June-July, 1977, 5 fig.
Descriptors: *Crop response, *Temperature, *Moisture stress, *Instrumentation,
Crop production. Air temperature, Irrigation practices, Transpiration, Evapora-
tion, Canopy, Satellites (artificial), Data collections, Farm management, Soil-
water-plant relationships.
A plant with adequate soil moisture is able to transpire water and keep its
leaves cooler than the surrounding air temperature; leaves transpire less and
grow warmer as moisture becomes scarce. A thermal scanning device to measure
crop stress has been developed; present and future technology of this type is
described. Infrared thermometers can indirectly measure surface temperatures
by measuring the radiant thermal energy emitted from a leaf surface. To calcu-
late the stress degree day figure, a farmer measures the temperature of the crop
canopy and the air just above the crop an hour or so after solar noon. Readings
from aircraft or satellites require two measuring times, one just before dawn
for the minimum air temperature and one after noon for the maximum. Results
of measurements from several crops indicate that as the midday canopy temperature
increases in comparison to the midday air temperature above the canopy, moisture
stress increases and crop yield declines. Application of the results is out-
lined .
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SECTION XI
WATER SUPPLY AUGMENTATION AND CONSERVATION
SALINE WATER CONVERSION (GROUP 03A)
77:03A-001
AN ASSESSMENT OF IRRIGATION EFFICIENCIES AND DRAINAGE RETURN FLOWS FROM THE
WELLTON-MOHAWK DIVISION OF THE GILA PROJECT,
Krull, D.L., and Clark, D.L.
United States Department of the Interior, Bureau of Reclamation, Yuma Projects
Office, Yuma, Arizona.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 335-348, May 16-19, 1977,
5 fig, 4 ref.
Descriptors: Desalination, Arizona, Irrigation efficiencies, Drainage, Return
flows, Drainage water, Irrigation.
Public Law 93-320 authorized the construction of a large desalting plant to
enable the United States to comply with its obligation under the agreement with
Mexico of August 30, 1973 (Minute No. 242 of the International Boundary and
Water Commission, United States and Mexico), The desalting plant will be con-
structed to treat the drainage waters from the Wellton-Mohawk Division of the
Gila Project so these waters will be available for delivery to Mexico under the
1944 Mexican Water Treaty and Minute No, 242, By reducing the volume of drainage
flows, the size of the desalting plant can be reduced. An interagency committee
was established to determine and implement means of increasing irrigation effi-
ciencies so as to reduce drainage return flows to the lowest practical volume
and to identify an optimal economic solution relating desalting costs to specified
irrigation efficiency levels. An assessment was made utilizing the water budget
process to determine the relationship between increased irrigation efficiency
levels and drainage return flows.
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SECTION XII
WATER SUPPLY AUGMENTATION AND CONSERVATION
WATER YIELD IMPROVEMENT (GROUP 03B)
77:03B-001
AUGMENTING SUMMER STREAMFLOW BY USE OF A SILICONS ANTITRANSPIRANT,
Belt, G.H., King, J.G., and Haupt, H.F.,
Idaho University, College of Forestry, Wildlife and Range Sciences, Moscow,
Idaho.
Water Resources Research, Vol. 13, No. 2, p 267-272, April 1977. 4 fig, 1 tab,
20 ref.
Descriptors: *Streamflow, *Transpiration control, *Idaho, Emulsions, Aqueous
solutions, Transpiration, Soil water, Watersheds (.basins), Regression analysis,
Seasonal, Summer, Spraying.
A 65-acre (26.3-ha) cedar-hemlock catchment in northern Idaho was sprayed with a
5% aqueous emulsion of silicone soil to reduce transpiration. The antitranspirant,
Dow Corning XEF-4-3561, was applied by helicopter at the rate of 40 gal/acre
(375 1/ha). From June 1 to September 15, 1974, streamflow, soil water, and leaf
water potential were monitored on the 65-acre (26,3 ha) treated watershed and
on an adjacent 50-acre (20.2 ha) control watershed. By using the paired water-
shed method with regression equations based on 6 years of pretreatment data,
predicted and observed streamflow were obtained for the period June 1 to Septem-
ber 15. Differences between predicted and observed streamflow were compared by
using the paired "t" test and were found to be significant at the 97.5% confi-
dence level. During a 63-day period, a 12% increase in streamflow resulted from
the antitranspirant application. During the same period, soil water storage
was greater on the treated watershed than on the control watershed; however,
the difference was not statistically significant. Seasonal leaf water potential
in cedar indicated that stress was greater on the control watershed than on the
treated watershed. Systematic differences in leaf potential for hemlock did
not occur.
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SECTION XIII
WATER SUPPLY AUGMENTATION AND CONSERVATION
USE OF WATER OF IMPAIRED QUALITY (GROUP 03C)
77:03C-001
INFLUENCE OF SEED PRETREATMENTS ON SALT TOLERANCE OF COTTON DURING GERMINATION,
Channon, M.C., and Francois, L.E,
Agricultural Research Service, Salinity Laboratory, Riverside, California.
Agronomy Journal, Vol. 69, No. 4, p 619-622, July-August, 1977. 3 fig, 1 tab,
20 ref.
Descriptors: *Seed treatment, *Salt tolerance, *Germination, *Cotton, *Saline
soils, Salinity, Arid lands. Salts, Sodium chloride, Saline water, Seeds, Irri-
gated land, Crop production, Irrigation water, Irrigation, Stress, Soil-water-
plant relationships, Semiarid climates,
A study was conducted to determine if various seed pretreatments could increase
the salt tolerance of a commercial variety of long-staple cotton (Gossypium
barbadense L.). Salts, phytohormones, and adenosine monophosphate were used in
twelve pretreatments (including a dry control and a distilled water control),
and their effectiveness tested by germinating the seeds in single and mixed
salts of NaCl and CaC12, as well as distilled water. No evidence was found that
pretreatment increases salt tolerance during germination. The beneficial effects
seem limited to water pretreatment which hastened the germination of seed by one
day over dry controls. A single four-hour soaking was optimal. This is hardly
noteworthy under optimum field conditions, but under stress conditions it may
be significant.
77:03C-002
OPTIMIZING CROP PRODUCTION THROUGH CONTROL OF WATER AND SALINITY LEVELS IN THE
SOIL,
Stewart, J.I., Hagan, R.M,, Hanks, R.J., Franklin, W.T., and Pruitt, W.O.
Utah Center for Water Resources Research, and Consortium for International
Development, Logan, Utah.
Available from the National Technical Information Service, Springfield, Virginia
22161 as PB-275 466, Utah Water Research Laboratory, Logan, Utah. Publication
PRWG151-1, September 1977, 191 p, 71 fig, 10 tab, 21 ref, 7 append.
Descriptors: *0ptimization, *Crop production, *Soil water, *Salinity, *Irrigation,
*Soil moisture, *Water management (applied), Saline water, Soil analysis, Plant
growth, Moisture content, Root zone, Model studies.
The research was carried out by four universities belonging to the Consortium for
International Development (CID) in cooperation with the four Water Research Centers,
Similar field experiments with corn were carried out in 1974 and 1975 at the
University of Arizona (Yuma Field Station), the University of California (Davis),
Colorado State University (Fort Collins), and Utah State University (Logan), The
objectives were to develop production functions for estimating how crop yield is
influenced by different levels of salinity and water supply at different stages of
crop growth, and to formulate and test models for predicting yields as a function
of water and salinity stress across a broad spectrum of climate and soil types.
A unique and significant feature of the study was the establishment of a suf-
ficient data base to test the transferability of the results, and to accomplish
this feature, the research was conducted on a regional basis with data collection
at the four different locations. All irrigation was applied with a line source
sprinkler system, developed in Utah, which gave a continuously variable amount of
irrigation water on each side of the line. The maximum evapotranspiration (ET)
was estimated at all locations and measured with lysimeters at California. Evapo-
transpiration (ET) was calculated at all plots as the sum of precipitation, irri-
gation, and soil water depletion minus drainage (estimated). Yields of dry matter
120
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and grain were measured at the end of each growing season. This study has
provided an extensive data base on how corn yields respond to moisture defi-
ciency and salinity stress under different soil and climatic conditions.
121
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SECTION XIV
WATER SUPPLY AUGMENTATION AND CONSERVATION
CONSERVATION IN AGRICULTURE (GROUP 03F)
77:03F-001
METHOD FOR EVALUATING IRRIGATION PROJECTS,
Hogg, B.C., and Vieth, G.R.
Economic Research Service, Natural Resource Economics Division, Washington, D.C.
Journal of the Irrigation and Drainage Division, Proceedings of the American
Society of Civil Engineers, Vol. 103, No. IR1, Proc. Paper No. 12828, p 43-52,
March 1977. 2 fig, 3 tab, 9 ref.
Descriptors: *Irrigation, *Project feasibility, *Project planning, *Evaluation,
*Crop production, *Return (monetary), *Methodology, Agriculture, Cost-benefit
ratio, Evapotranspiration, Prices, Variability, Water distribution (policy),
Optimization, Equations, Systems analysis, Mathematical models, Risks, Hawaii,
Evaporation pans.
A methodology is presented for evaluating irrigation projects by comparing the
performance of alternative system designs over a planning period specified by the
user. The estimating model is based on a universal crop production function for
water which is utilized to optimize interzonal water distribution. A solution is
optimum if: (1) the value of product resulting from the last unit of water applied
divided by the marginal cost of water (in this case the unit cost) is the same for
all zones; (2) the value of product for the last unit of irrigation is not less
than its cost; (3) there can be no negative irrigation levels, i.e., the interzonal
transfer of rainfall; and (4) the total amount of irrigation water applied does
not exceed the quantity available. Project zones are defined by climate, soil,
and crop produced. Price and climatic uncertainty are dealt with directly in the
model assuming the probability distribution of the respective variable is known.
The measures of economic viability available for comparing alternative system
designs include: the benefit/cost ratio, internal rate of return, and net present
worth. Presented is an illustrative examplea single sugar plantation occupying
multiple climatic zones and operating under conditions of price and climatic
uncertainty-
77:03F-002
MINIMIZING CANAL CAPACITY FOR IRRIGATED RICE,
Hagan, R.E., and Wang, J-K.
Hawaii University, Department of Agricultural Engineering, Honolulu, Hawaii.
Journal of the Irrigation and Drainage Division, Proceedings of the American
Society of Civil Engineers, Vol. 103, No. IR1, Proceedings Paper No. 12821,
p 71-78, March 1977. 3 fig, 3 ref.
Descriptors: *Canal design, *Irrigati6n, *Rice, *Conveyance structures, Rota-
tional flow, Efficiencies, Surface irrigation, Water demand. Equations, Systems
analysis.
Improved formulas are developed for calculating the maximum canal or pump capa-
city needed for lowland rice rotational irrigation system design. The conven-
tional and modified conventional formulas are derived from assumptions that
cannot be satisfied during irrigation system operation. This induces water usage
and management inefficiencies into the system. Analysis of the conventional
and modified conventional formulas with the rotational irrigation system manage-
ment practices isolates several criteria to be used in integrating design and
operation. By this integration, irrigation system efficiency is increased.
The maximum capacity given by the improved formulas is smaller than that required
by the conventional and modified conventional formulas. This allows the use of
smaller canals or an enlargement of the area, or both, serviced by a given water
supply flow rate.
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77:03F-003
IRRIGATION SYSTEM OPERATING POLICIES FOR MATURE TEA IN MALAWI,
Palmer-Jones, R.W.
Institute for Agricultural Research, Zaria (.Nigeria)
Water Resources Research, Vol. 13, No. 1, p 1-7, February 1977. 2 fig, 3 tab,
15 ref.
Descriptors: Irrigation systems, *Crop response, *Soil moisture, *Dynamic
programming, Optimization, Effects, Rainfall, Equations, Mathematical models,
Simulation analysis, Systems analysis, Water supply, Operations.
The technical specification of plant-water relationships has led to errors in the
formulation of response models for water inputs. Consequently, the optimizing
procedures making use of these models may have been misleading as to both the
practical water application rules recommended and the usefulness of the optimizing
procedure. In this paper, it is shown that the distribution of water within the
root zone, specifically for tea in Malawi, plays an important part in determining
response to irrigation. This means that two or more soil moisture state variables
will be necessary in the dynamic programming (DP) method of finding the optimal
application policy, and this makes DP even more difficult to use in practice than
has been previously indicated. It is shown that response to irrigation depends
on the amount of water in the uppermost layer of the soil and that the effect of
an irrigation on yield is through its effect on the current level of this variable
and on its future levels through the effect of current irrigation on the water
contents of lower layers of the soil. Optimal applications are found to be deter-
mined by two variables: the water content of the uppermost layer (.30 cm) and the
water content of the remainder of the root zone. The optimal system distribution
policy capacity is found to be close to the level that would just replace the
maximum deficit that could build up in the uppermost layer between irrigation
rounds.
77:03F-004
TRICKLE IRRIGATION AND FERTILIZATION OF TOMATOES IN SAND DUNES] WATER, N, AND
P DISTRIBUTIONS IN THE SOIL AND UPTAKE BY PLANTS,
Bar-Yosef, B,
Agricultural Research Organization, Division of Soil Chemistry and Plant Nutrition,
Bet Dagan (Israel).
Agronomy Journal, Vol. 69, No. 3, p 486-491, May-June, 1977. 1 fig, 11 tab,
8 ref.
Descriptors: *Irrigation effects, *Fertilization, *Tomatoes, *Dune sands, *Nu-
trient requirements, Moisture uptake, Soil-water-plant relationships, Crop pro^
duction, Crop response, Nitrogen, Irrigation practices, Soil water,- Water utili-
zation, Root zone, Leaching, Phosphorus.
Various daily rates of water, N, and P were applied through a trickle irrigation
system to tomato plants (Lycoperisicum esculentum Mill,) grown on coastal dunes
of fine sand in southern Israel. Fruit yields were greatest (.about 110 tons/ha)
when the daily average water content in the soil root volume was around 5%(w/w),
N concentration in the soil solution 140 + or -40 ppm N, and N uptake rate about
100 mg N/plant/day, Daily water consumption varied from 0,4 to 1.0 liter/plant/
day, depending on leaf area and climatic conditions, In general, water use ef-
ficiency decreased with time. The amount of water used to produce 1 g dry matter
was similar in all treatments (about 250 + or -40 g water/g d.m.). Plants ab-
sorbed 30 to 50% of the added N, this low recovery probably due to leaching losses.
77:03F-005
A NEW APPROACH FOR ESTIMATING IRRIGATION CONVEYANCE LOSSES AND THEIR ECONOMIC
EVALUATION,
Palacios, E.V., and Day, J.C.
Escuela Nacional de Agriculture, Colegio de Postgraduados, Chapingo (Mexico).
Water Resources Bulletin, Vol. 13, No. 4, p 709-719, August 1977. 1 tab, 2 fig,
5 ref.
125
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Descriptors: *Irrigation systems, *Canals, *Economic feasibility, Methodology,
Irrigation districts, Mexico, Statistical methods, Water management (applied),
Networks, Flow, Costs, Benefits, Estimating, Evaluation, Water supply, Water
delivery, Regression analysis, Equations, Mathematical models. Systems analysis.
A new methodology for estimating conveyance efficiency within irrigation systems
is presented. Based on statistical analysis of daily water releases from the
source of supply and deliveries to the farmers in an irrigation district in Mexico,
a linear model is obtained for estimating conveyance efficiency and two compo-
nent factors. One of these factors points out the relative importance of the
operational losses (for example, losses due to water management), and the other
shows the importance of the fixed losses which can be attributed to the average
flow through the canal network without variations. Next, an analysis of the
expected benefits and costs accruing from system improvement permits derivation
of a decision rule which may be used in analyzing the economic feasibility of
lining in-place canals. Results show that conveyance efficiency may be signifi-
cantly increased by improving the operating rules in an irrigation system, this
being the cheapest way of attaining the improvement. However, since many vari-
able factors may affect the economic feasibility of lining canals, careful
studies should be made regarding infiltration rate measurements, cost of lining,
days of effective operation per year of each canal, etc., before making decisions
regarding the lining of the canal in question.
77:03F-006
REGULATION OF GRAIN YIELD BY PHOTOSYNTHESIS IN MAIZE SUBJECTED TO A WATER
DEFICIENCY,
McPherson, H.G., and Boyer, J.S.
Department of Scientific and Industrial Research, Plant Physiology Division,
Palmerston North (New Zealand).
Agronomy Journal, Vol. 69, No. 4, p 714-718, July-August, 1977. 6 fig, 1 tab,
30 ref.
Descriptors: *Photosynthesis, *Moisture deficit, *Crop production, *Translocation,
Corn (field), Crop response, Grains (crops), Moisture uptake, Plant physiology,
Droughts, Plant growth.
Drought causes massive losses in the yield of crops, but the physiological mech-
anisms responsible for decreased yields are poorly understood. Experiments were
conducted on maize plants to attempt to identify these mechanisms. The plants
were subjected to a water deficiency during most of the grain filling period.
They were grown in a controlled environment capable of providing yields comparable
to the field. Grain yields, dry weights of shoots and roots, apparent photosyn-
thesis, and leaf water potential were determined. The results are presented. At
low leaf water potentials, the grain developed partly at the expense of photosyn-
thesis accumulated prior to the desiccation period. Since grain development is
dependent entirely on translocation in maize, this indicated that translocation
continued despite the cessation of apparent photosynthesis, Translocation is
less inhibited than photosynthesis accumulation for the growing season controls
yield during a drought.
77:03F-007
THE ROLE OF EPA'S OFFICE OF RESEARCH AND DEVELOPMENT IN IRRIGATED CROP PRODUCTION
RESEARCH,
Law, J.P., Jr., and Hornsby, A.G.
United States Environmental Protection Agency, Environmental Research Laboratory,
Office of Research and Development, Ada, Oklahoma.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 1-6, May 16-19, 1977.
1 fig.
Descriptors: Water quality control, Water pollution, Irrigation, Irrigated land,
Water management (applied). Return flow, Research and development, Agricultural
activities, Wastewater management.
In setting the stage for the conference, the role of the Irrigated Crop Production
research program will be described. The legislative mandates of PL 92-500 to EPA
will be reviewed in relation to the charge to control water quality degradation
-------
resulting from agricultural activities. The overall objectives of the program,
established prior to the passage of PL 92-500, appear to be valid and supportive
of the efforts of the program thus far. This conference represents a compendium
of the results of the program's efforts as well as a hard look at the future
direction the program should take. Supported research has included technology
development and evaluation of its effectiveness in water pollution abatement
and/or control. The technology investigated has included both structural and
nonstructural improvements within the water delivery, farm, and water removal
subsystems of irrigated agriculture. Additional studies have investigated the
legal, socio-economic, and/or other institutional constraints to water manage-
ment reform. More effort will be required in these areas. Current program em-
phasis is evolving into a phase which we are referring to as implementation re-
search. Included in this is the preparation of research-based guidance documents
aimed at providing much needed information for those state agencies responsible
for planning and implementing areawide wastewater management alternatives involving
nonpoint source agricultural activities. The discussions of this conference
should provide great impetus toward that goal,
77:03F-008
SCIENTIFIC IRRIGATION SCHEDULING FOR SALINITY CONTROL OF IRRIGATION RETURN FLOW,
Jensen, M.E.
United States Department of Agriculture, Snake River Conservation Research Center,
Kimberly, Idaho.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 133-139, May 16<-19, 1977.
3 tab, 6 ref.
Descriptors: Model studies, Irrigation water, Leaching, Return flow, Irrigation
efficiency, Evapotranspiration.
Basic principles of irrigation water management and irrigation scheduling are
presented. Commercial and agency groups expanded rapidly in the 1970*s providing
field-by-field scheduling services to over 600,000 acres in 1976. The leaching
fraction used on projects can effect return flow quality. Most leaching fraction
return flow models hypothetically assume uniform water applications of exact
quantities to attain targeted leaching fractions, The average or effective leach-
ing fraction for a field is dependent on the irrigation uniformity coefficient.
The effects of nonuniform water application on average leaching fractions will be
presented, along with the probable effects of expected improvements in irrigation
efficiency on return flow. Also, estimates of the accuracies in estimating
evapotranspiration and measuring water will be presented. Substantial improve-
ments can be made in irrigation efficiencies before minimum leaching fractions are
reached on most western irrigated projects.
77:03F-009
DRIP/TRICKLE IRRIGATION GENERATING GROWTH, OPTIMISM,
Ross, R.
Irrigation Age, Vol. 11, No. 3, p 14-16, November^December, 1976. 1 fig,
Descriptors: *Irrigation practices, Irrigation, Irrigation systems,. Water con^
servation, Irrigation efficiency.
Irrigation Age, in a series of personal interviews during the International
Drip Irrigation Association meeting, spoke to several representatives of various
drip/trickle industry segments.
77:03F-010
WATER MOVEMENT IN BARE AND CROPPED SOIL UNDER ISOLATED TRICKLE EMITTERS: I,
ANALYSIS OF BARE SOIL EXPERIMENTS,
Jury, W.A., and Earl, K.D.
California University, Department of Soil Science and Agricultural Engineering,
Riverside, California 92502.
Soil Science Society of America Journal, Vol. 41, No. 5, p 852-856, September<-
October, 1977. 8 fig, 1 tab, 12 ref.
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Descriptors: Hydraulic conductivity, Soil water, Soil water movement, Tensio-
meters, Sampling, Irrigation, Irrigation effects, Irrigation practices, Irriga-
tion systems.
A field experiment on a Buren sandy loam with a low (0.5 centimeters per hour)
saturated hydraulic conductivity is reported in which water movement in soil ir-
rigated from a single isolated trickle emitter was observed. Water was intro-
duced at a uniform rate of 4 liters per hour and a weekly volume of 84 liters
at frequencies of 3 irrigations per day and 1 irrigation per week. During a
41-day experiment, soil water movement was followed by tensiometers and gravi-
metric water content sampling, and surface ponding was recorded by photography.
It was found that more water moved laterally in the weekly irrigation plots
than in the daily ones, a result which was not consistent with predictions of
simplified theoretical models which did not consider surface ponding. Observa-
tion of the wetted radius at the surface indicated that substantial amounts of
water were running off laterally during the weekly irrigation, which could
account for the storage changes seen at large radial distances from the emitter.
77:03F-011
WATER MOVEMENT IN BARE AND CROPPED SOIL UNDER ISOLATED TRICKLE EMITTERS: II.
ANALYSIS OF CROPPED SOIL EXPERIMENTS,
Earl, K.D., and Jury, W.A.
California University, Department of Soil Science and Agricultural Engineering,
Riverside, California 92502.
Soil Science Society of America Journal, Vol. 41, No. 5, p 856-861, September-
October, 1977. 6 fig, 4 tab, 21 ref.
Descriptors: Hydraulic conductivity, Soil water, Soil water movement, Tensio-
meters, Sampling, Irrigation, Irrigation effects, Irrigation practices, Irrigation
systems, Root systems, Crop response, Evapotranspiration.
Soil moisture and plant root distributions were evaluated when plots of summer
squash were trickle irrigated with two contrasting frequencies of water applica-
tion. Replicated plots receiving the same total volumes of water were irrigated
three times daily and once weekly, with irrigation volumes adjusted according to
evapotranspiration and tensiometric data. In the presence of actively growing
zucchini, weekly irrigations produced a greater movement of water both laterally
and vertically downward than daily irrigations. Plant roots were distributed
according to the wetted volume of soil, with roots of weekly irrigated plots
being more evenly distributed than in daily irrigated plots where roots were con-
centrated beneath the emitter. The imposition of a water stress demonstrated a
marked increase in root density beneath the emitters as a result of proliferation
of fine root material. Zucchini yields in the outer ring of weekly irrigated
plants (100 centimeters from emitter radially) were 30 percent higher than the
most productive daily irrigated plot. Furthermore, total green matter and dry
matter yields were greater in weekly irrigated plots,
77:03F-012
THE PRODUCTION OF PHYTOTOXINS FROM SURFACE CROP RESIDUES,
Cochran, V.L,, Elliott, L.F., and Papendick, R.I.
United States Department of Agriculture, Agricultural Research Service, Western
Region, Pullman, Washington 99164.
Soil Science Society of America Journal, Vol. 41, No. 5, p 903-908, September*-
October, 1977. 6 fig, 1 tab, 20 ref.
Descriptors: Crop production. Crop response, Washington, Micro organisms, Blue^
grasses, Soils, Soil investigations, Organic matter.
Experiments were conducted to determine if crop residues, common to eastern Wash-
ington, were likely to cause phytotoxicity problems with no-till planting of
winter wheat. The possible role of microorganisms was assessed also. Mats of
pea, wheat, barley, and bluegrass residues were spread over bare soil in September
of 1975. Water extracts of the residues and soil beneath them were bioassayed
weekly for wheat-seedling phytotoxins and the residues were plated biweekly to
determine the numbers of fungi, bacteria, and pseudomonads from September of 1975
through May 1976. All residues produced wheat-seedling root inhibitors, but only
after conditions became favorable for microbial growth.
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77- 03F-013
THE BIOLOGY AND MODELLING OF FERTILIZER RESPONSE,
Helyar, K.R., and Godden, D.P.
New South Wales Department of Agriculture, Agricultural Research Centre, Depart-
ment of Agronomy, Wollongbar, N.S.W., 2480.
Journal of the Australian Institute of Agricultural Science, Vol 43 No 1 & 2
p 22-30, March-June, 1977. 7 fig, 17 ref, 16 equ, 1 append.
Descriptors: Nutrients, Fertilizers, Fertilization, Soil investigations, Crop
response, Crop production, Model studies.
A theory has been presented which can be used to account for the native soil
nutrient status, residual effects of past fertilizer applications and the effect
of current fertilizer application on plant yield. The procedure enables the
partitioning of fertilizer between inputs required to balance losses and inputs
required to build up soil nutrient reserves. Because of this feature, a logical
basis for the economic analysis of fertilizer response and for understanding
the practical significance of observable responses is provided,
77:03F-014
NITROGEN RESPONSES OF TALL FESCUE AND RYEGRASS SURVIVOR POPULATIONS FROM A RATE-
OF-NITROGEN EXPERIMENT,
Harris, W., and Lazenby, A.
New England University, Department of Agronomy and Soil Science, Armidale,
New South Wales 2351, Australia.
New Zealand Journal of Agricultural Research, Vol. 20, No. 3, p 327-330, August
1977. 2 tab, 8 ref.
Descriptors: Nitrogen, Fertilizers, Fertilization, Nutrients, Crop production,
Crop response, Grasses.
Survivor populations of ryegrass and tall fescue from an experiment in which
nitrogen was applied at rates of 0 to 1344 kg/ha/year were tested for nitrogen
response in the range from 0 to 4352 kg N/ha in a single application. Applications
above 544 kg N were supra-optimal and were totally toxic at 4352 kg N, There
were no indications of adaptation of the different survivor populations to either
sub-optimal or supra-optimal levels of nitrogen.
77:03F-015
ISOTOPIC STUDIES ON THE UPTAKE OF SULPHUR BY PASTURE PLANTS, I, A METHOD FOR THE
DIRECT INTRODUCTION OF 35S ISOTOPE INTO THE SOIL PROFILE UNDER FIELD CONDITIONS,
Goh, K.M., Gregg, P.E.H., Brash, D.W., and Walker, T.W.
Lincoln College, Department of Soil Science, Canterbury, New Zealand.
New Zealand Journal of Agricultural Research, Vol. 20, No. 2, p 221-227, May 1977,
6 fig, 3 tab, 22 ref.
Descriptors: Isotope studies, Sulphur, Soil investigations. Soil profiles, Pas-
tures, Pasture management, Root systems, Soil chemistry, Soil chemical properties,
A method for the direct introduction of 35S isotope into different soil depths
under field conditions to study the uptake of sulphur by pasture plants is described.
This method was designed to minimize bias and contamination during the introduction
of the isotope. It involved the horizontal introduction of the isotope enclosed
in water-soluble capsules. Recovery of 35S by the pasture plants indicated that
when 35S was introduced at a depth of 22 centimeters the area above ground in which
pasture plants were labeled extended little more than 15 centimeters from the line
of placement. This lateral spread of 35S in the pasture plants varied according
to the soil and the depth of application. The results may be explained in terms
of the extent and nature of root development in the soil profile,
77:03F-016
ISOTOPIC STUDIES ON THE UPTAKE OF SULPHUR BY PASTURE PLANTS, II. UPTAKE FROM
VARIOUS SOIL DEPTHS AT SEVERAL FIELD SITES,
Gregg, P.E.H., Goh, K.M., and Brash, D.W.
Ministry of Agriculture and Fisheries, Research Division, Christchurch, New Zealand,
New Zealand Journal of Agricultural Research, Vol. 20, No. 2, p 229-233, May 1977,
5 tab, 10 ref.
127
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Descriptors: Isotope studies, Sulphur, Soil investigations, Soil profiles, Pas-
tures, Pasture management, Root systems, Soil chemistry. Soil chemical properties.
On two contrasting soils, Kowai sandy loam (recent soil) and Gorge silt loam (low-
land yellow-brown earth) in inland Canterbury, New Zealand, plant uptake of 35S-
sulphur placed at various soil depths and also the uptake of associated soil sul-
phur (32S) present at the same depths were investigated in developed pastures
under field conditions. Results from the first harvest in'the spring of 1972 showed
that on both soils white clover and perennial ryegrass plants used sulphur from all
four depths studied (for example, 7.5, 22.5, 37.5, and 52.5 cm).
77:03F-017
POLICY ALTERNATIVES FOR THE PRESERVATION OF AGRICULTURAL LAND USE,
Lapping, M.B.
Vermont University, Environmental Program and School of Natural Resources,
Burlington, Vermont 05401.
Journal of Environmental Management, Vol. 5, No. 3, p 275-287, July 1977. 3 tab,
31 ref.
Descriptors: Agriculture, Land use, Land resources, Land development, Land
classification, Land, Rural area.
Increasing demands for food and fiber are making the retention and preservation
of prime agricultural land a focus of contemporary land policy. This is a
particular problem in the United States and other industrialized nations where
pressures to convert agricultural land to other uses are strong and sustained.
Various measures and strategies to maintain farmland are examined and critiqued.
The paper concludes with the recommendation that the state or provincial level
of administration can be most effective in the preservation process, and that a
wide array of programs and strategies is essential to meet local environmental
differences.
77:03F-018
WATER SHORTAGE IN ISRAEL: LONG-RUN POLICY FOR THE FARM SECTOR,
Gisser, M., and Pohoryles, S.
New Mexico University.- Department of Economics, Albuquerque, New Mexico,
Water Resources Research, Vol. 13, No. 6, p 865^-872, December 1977. 1 fig,
5 tab, 4 ref.
Descriptors: *Water shortage, *Incoine, *Linear programming, *Estimating, *Water
allocation (policy), Agriculture, Water supply, Data, Technology, Economic ef-
ficiency, Constraints, Regions, Mathematical models, Systems analysis.
In the year 1985, it is expected that Israel will suffer a significant deficit in
its water balance; this country faces a situation of limited water supply and
increasing demands. Since agriculture uses a large fraction of the available
water, one potential policy is to reduce allocations of water to agriculture in
order to permit the growth of its use in other sectors. A linear programming
model is used to estimate the total loss in income to agriculture from reduction
in current allocations; these estimates are to be taken as guideline estimates
only. Results show that a 10%, 20%, or 301 reduction in water quotas will give
rise to roughly a 6%, 12%, or 18% reduction in farm income if no technological
change is assumed. If technological changes are supposed, then the reductions in
agricultural income will be 1%, 7%, and 12%, respectively- Policy recommendations
are given: (1) use the extension services to help farmers in the moshavim to
switch from the moshav dairy farm to a large-scale water-efficient kibbutz-type
farm; (2) provide the loans that would be needed for the above transformation;
(3) to enhance intrasector efficiency, encourage farmers to trade in water quotas
on the margin, and this would work only if the practice were to (.4) charge the
real marginal cost on the margin (the margin should cover 15%-21%).
77:03F-019
WATER TABLE DEPTH AND IRRIGATION EFFECTS ON WATER USE EFFICIENCIES OF THREE CROPS,
Benz, L.C., Reichman, G.A., Doering, E.J., and Follett, R.F.
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United State's Department of Agriculture, Agricultural Research Service, Northern
Great Plains Research Center, Mandan, North Dakota.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State Univer-
sity, p 1-17. 7 fig, 3 tab, 14 ref.
Descriptors: Irrigation, Irrigation efficiency, Corn, Sugar beets, Water table,
Irrigation effects, Irrigation practices, Alfalfa.
Production and applied water-use efficiencies (AWUE) of corn, sugar beets, and
alfalfa from a 3-year field experiment at three water table depths and four ir-
rigation rates were highest from the shallow water table treatment without ir-
rigation, regardless of irrigation treatment.
77:03F-020
LIMITED TILLAGE SAVES SOIL, WATER, AND ENERGY,
Allen, R.R., and Pryrear, D.W.
United States Department of Agriculture, Southwestern Great Plains Research
Center, Bushland, Texas.
Presented at the 1977 Annual Meeting, American Society of Agricultural Engineers,
June 26-29, 1977, Raleigh, North Carolina, North Carolina State University, p 1-14.
6 tab, 22 ref.
Descriptors: Herbicides, Soil conservation, Erosion, Runoff, Soil moisture, Soil
water, Agriculture, Mulching, Nebraska, Crop production.
Limited and high cost energy since 1973 has added to the pressures upon agricultural
production. This paper discusses how limited tillage can conserve energy as well
as soil and water on the Great Plains. Stubble-mulch tillage, which began on the
Great Plains for wind erosion control, was the forerunner of present limited til-
lage systems. Stubble-mulch reduced annual wind erosion from 6.5 to 2.0 metric
tons/ha in western Nebraska and increased wheat production by 13 percent at
Bushland, Texas, while using equal or less energy than clean tillage. Use of
herbicides, or herbicides plus sweep tillage on fallow, increased soil water stor-
age and reduced energy use in Kansas, Nebraska, and Texas. On sandy soils of the
Southern Great Plains, crops such as cotton may not leave enough residue to pre-
vent soil blowing. This may require additional energy to spread a mulch such as
cotton gin trash or perform emergency surface-roughening tillage. With deep well
irrigation of crops, energy for tillage is overshadowed by energy to pump water
and manufacture fertilizer. Pumping and fertilizer energy can be 10 to 25 times
higher than for tillage.
77:03F-021
PULSE IRRIGATIONDESIGN. FOR OPERATING SETS,
Karmeli, D., and Peri, G.
Colorado State University, Department of Agricultural Engineering, Fort Collins,
Colorado.
Journal of the Irrigation and Drainage Division, Proceedings of the American
Society of Civil Engineers, Vol. 103, No. IRl, p 33-41, March 1977. 1 fig, 3
tab, 1 ref.
Descriptors: Irrigation efficiency, *Pumping, *Design, Operations, Irrigation
practices, Discharge (water), Equations, Irrigation systems.
A process of design for operating sets with pulse irrigation has been developed.
The process allows for an efficient operation and also adjusts the operating
sets to the characteristics of the pulse as formulated in a previous work. The
adjustment expresses itself mainly in the establishment of the number of stations
operating with one pulsator and in the various parameters of the pulse. The
process allows for the design of a number of sets and stations when the total
duration of irrigation and total number of valves in the field are given. The
number of sets and stations per set must be established so as to have identical
numbers of stations per set. The characteristics of the remaining stations will
be different as the number is smaller and the duration time of operation is
maximal.
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77:03F-022
EFFICIENT AND INEFFICIENT USE OF PHOSPHORUS BY SORGHUM,
Brown, J.C., Clark, R.B., and Jones, W.E.
United States Department of Agriculture, Agricultural Research Service, Plant
Stress Laboratory, Beltsville, Maryland 20705.
Soil Science Society of America Journal, Vol. 41, p 747-750, July-August, 1977,
3 fig, 5 tab, 22 ref.
Descriptors: Phosphorus, Sorghum, Nutrients, Soils, Crop response, Fertilizers.
Twelve genotypes were grown on acid-Bladen soil (pH 4.3, P stressed or Al toxic),
on limed-Bladen soil (pH 5.2, Cu stressed), and on alkaline Quinlan soil (pH 7.5,
Fe stressed!) to determine the effect of P efficiency on use of these elements by
the plants. Under P-stress or Al-toxicity conditions, the most P-efficient
sorghum genotypes absorbed more 32P than the most P-inefficient lines and grew
normally, while the P-inefficient plants developed P deficiency symptoms. Under
Fe-stress conditions, the most P-efficient genotypes developed Fe chlorosis,
while the most P inefficient plants remained green. Under Cu-stress conditions,
one of six genotypes developed severe Cu-deficiency symptoms, characterized by
the accumulation of higher P in the lower leaves, and by lower Fe and Ca in upper
leaves of Cu-stressed plants as compared with Cu-sufficient plants. Thus, P
efficiency in plants may be an asset when P availability limits growth, but it
may be a liability when these same plants are subjected to Fe or Cu stress.
77:03F-023
EFFECT OF IRRIGATION SYSTEMS ON THE WATER REQUIREMENTS OF SWEET CORN,
Wendt, C.W., Onken, A.B., Wilke, O.C., Hargrove, R., and Bausch, W.
Texas A and M University Agricultural Research and Extension Center, Texas Agricul-
tural Experiment Station, Lubbock, Texas.
Soil Science Society of America Journal, Vol. 41, No. 4, p 785-788, July-August,
1977. 3 fig, 2 tab, 14 ref.
Descriptors: Irrigation, Irrigation systems, Sprinkler irrigation, Furrow ir-
rigation, Subsurface irrigation, Corn, Evapotranspiration, Tensiometers, Soil
moisture.
A field study was conducted to determine the influence of sprinkler irrigation
(Sp), furrow irrigation (F), subirrigation tSu), and automated subirrigation (ASu)
on the water requirements of sweet corn. Irrigation water was applied to the Sp,
F, and Su plots when the soil water potential at the 30-cm depth in the row reach-
ed -40 cbars potential. The time and amount of water applied was based on a
combination of leaf area index (LAI) and potential evapotranspiration (.ET(p)).
Water application to the ASu plots was controlled by a switching tensiometer 30 cm
deep set at -40 cbars potential. Soil water content changes were determined by
gravimetrically sampling the surface 15 cm and obtaining neutron probe measure-
ments of water in the deeper depths. Significant differences existed in the
irrigation water requirement of the sweet corn irrigated by the different sy-
stems (F = 351 mm, SP = 248 mm, Su = 248 mm, ASu = 142 mm), However, little
difference in consumptive use occurred between systems (F = 361 mm, Sp = 346 mm,
Su = 346 mm, ASu = 310 mm) due to differences in soil water utilization. Auto-
mation of irrigation systems offers the possibility of significantly enhancing
irrigation water use efficiency in supplementally irrigated areas,
77:03F-024
MANAGING FARMLAND TO IMPROVE WATER QUALITY,
Morrison, J.
Purdue University, Department of Agricultural Information, West Lafayette,
Indiana 47907.
Journal of Soil and Water Conservation, Vol. 32, No. 5, p 205^208, September^
October, 1977- 3 fig.
Descriptors: Indiana, Erosion, Runoff, Water quality, Water quality control,
Watersheds (basins), Agriculture.
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For five years a 12,000-acre watershed in the rich agricultural land of Indiana's
Maumee Basin has been under intensive study by researchers representing a variety
of disciplines and interests. The project was named after Black Creek, the area's
major drainageway. Investigations have touched on complex management, policy,
and scientific issues, but the fundamental questions are relatively simple. 1
What is the relationship between erosion in the Black Creek watershed and water-
quality in Black Creek, the Maumee River, and Lake Erie? 2. Can a program based
on voluntary participation by landowners, encouraged by cost-sharing incentives,
have much impact on either erosion or water quality?
77:03F-025
REGULATORY PROGRAMS FOR NONPOINT POLLUTION CONTROL: THE ROLE OF CONSERVATION
DISTRICTS,
Garner, M.M.
National Association of Conservation Districts, 1025 Vermont Avenue, N.W.,
Washington, D.C. 20005.
Journal of Soil and Water Conservation, Vol. 32, No, 5, p 199-204, September-
October, 1977. 4 fig, 32 ref.
Descriptors: Water quality, Water quality management, Water pollution, Water
pollution control, Water conservation.
Conservation districts are in a unique position to play a major role in state
and areawide water quality management plans developed under Section 208 of the
Federal Water Pollution Control Act Amendments of 19.72 (Public Law 92-500). These
districts, which in most states are local subdivisions of state government,
number about 3,000. They encompass virtually all the privately owned land in the
nation, including both rural and urban areas.
77:03F-026
CRITERIA AND STRATEGIES FOR MAINTAINING AGRICULTURE AT THE LOCAL LEVEL,
Derr, D., Small, L., and Dhillon, P.
Rutgers University.- Cook College, Department of Agricultural Economics and
Marketing, New Brunswick, New Jersey 08903,
Journal of Soil and Water Conservation, Vol. 32, No, 3, p 118-122, May-June, 1977,
3 fig, 13 ref.
Descriptors: Agriculture, Land use, Land development, Crop production. Urbanization,
Until recently, agricultural land was regarded as a reserve from which land needed
for other uses could be drawn with little regard for the impact on the producti-
vity of the remaining area. But the continued decline of agriculture near urban
areas has precipitated concern among people both in and out of agriculture.
77:03F-027
TECHNOLOGY DEVELOPMENT AND TRANSFER FOR NATURAL RESOURCES MANAGEMENT,
Saxton, K.E.
United States Department of Agriculture, Agricultural Research Service, Pullman,
Washington.
Journal of Soil and Water Conservation, Vol. 32, No, 3, p 123-125, May-June, 1977.
1 fig, 9 ref.
Descriptors: Technology, Natural resources, Agriculture, Economics, Environmental
control.
Conservationists, engineers, and planners are experts in applying technology to
achieve efficient natural resource use and safe, dependable structures. The tech-
nology they use represents years of experience and research. But as these pro-
fessionals know, current technology must be refined or replaced with improved
concepts and procedures if we are to achieve and maintain a cleaner environment,
economical farming with sustained high yields, and effective conservation practices.
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77:03F-028
DRIP SYSTEM EVALUATION,
Davids, G.
Harza Agricultural Services, Department of Agricultural Engineering.
Drip/Trickle Irrigation, Vol. 2, No. 2, p 20-21, March-April, 1977.
Descriptors: Irrigation systems, Irrigation efficiency, Irrigation practices,
Uniformity, Uniformity coefficient, Soil moisture.
In maintaining a soil moisture budget for any irrigation unit, one of the es-
sential pieces of input data is the net irrigation amount. When an irrigator
operates his system, it is essential to determine the net or effective irriga-
tion depth applied as accurately as possible. All drip/trickle systems should
have metering devices to measure flow volume or rates, so the gross irrigation
amount is easily verified.
77:03F-029
INSTALLATION OF DRIP IRRIGATION FOR ROW CROPS,
Chapin, R.
Chapin Watermatics, Post Office Box 298, Watertown, New York 13601.
Drip/Trickle Irrigation, Vol. 2, No. 2, p 9-11, March-April, 1977, 6 fig.
Descriptors: Irrigation systems, Irrigation practices, Crop production, Sub-
surface irrigation. Field crops, Irrigation design.
The installation of drip irrigation for row crops differs somewhat from that of
orchards for three reasons. First, the rows are closer together and consequently
require many more drip lines per acre. Second, with row crops much of the equip-
ment is moved out of the field between crops; however, in orchards, it remains
in the field permanently. Third, usually the submains are buried, and the drip
lines themselves may either be buried, or on the surface, Ori a typical instal-
lation, row length may be 1,200 feet or more,
77:O3F-030
MINIMUM SCREENING AND AUTOMATIC FLUSHING,
Shearer, M.N.
Oregon State University, Department of Extension Irrigation, Corvallis, Oregon.
Drip/Trickle Irrigation, Vol. 2, No. 2, p 14-16, March-April, 1977. 5 fig, 1 tab.
Descriptors: Filtration, Irrigation systems, Irrigation practices, Irrigation
water, Organic matter, Suspended solids, Surface water, Automation,
We previously reported the success Dr. Mellenthin had at the Hood River Experiment
Station in avoiding emitter plugging by using a self-cleaning, 200 mesh screen
and weekly flushing of laterals by hand. Although organic matter was present in
the ditch water, only 1 1/2% of the solid material flushed from the laterals was
organic. This year a variety of emitters were again used at the station with no
apparent plugging problems, except for microtube emitters, which exhibited vary-
ing degrees of flow reduction. However, labor to flush the individual laterals
was still a problem.
77:03F-031
ASSESSING PHOSPHORUS FERTILIZER NEEDS BASED ON INTENSITY-CAPACITY RELATIONSHIPS,
Lee, Y.S., and Bartlett, R,J.
Vermont University, Department of Plant and Soil Science, Burlington, Vermont
05401.
Soil Science Society of America Journal, Vol. 41, No. 4, p 710-712, July-August,
1977. 4 fig, 12 ref.
Descriptors: Phosphorus, Fertilizers, Fertilization, Soils, Soil investigations,
Crop response, Nutrients.
Phosphorus in a pH 4.8 NH40Ac soil extract, through crop response correlation
work, may indicate the degree to which a level of P in a given soil is optimum.
But, being an intensity measurement, this NH40AC-P value does not indicate the
amount of P fertilizer needed to bring a soil, which has a particular P sorption
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capacity, to its optimum level. The relationship between added P and the square
root of the NH40AC-P, measured after incubation of a given acid or limed soil,
was a straight line with a characteristic slope for that soil. The value of this
slope, termed the Phosphorus Fertilizer Index (PFI), showed a high correlation
with the amount of Al extracted by pH 4,8 NH40AC tsq r = 0.94), Inclusion of
soil chemical characteristics other than Al in the calculation did not improve
the P intensity-capacity relationships significantly.
77:03F-032
AMMONIUM EFFECTS ON NUTRIENT CATION ABSORPTION BY WHEAT,
Cox, W.J., and Reisenauer, H.M.
Department of Agriculture, South Perth, Western Australia 6151,
Agronomy Journal, Vol. 69, No. 5, p 868-871, September-October, 1977 1 fig, 3
tab, 18 ref.
Descriptors: Nutrients, Fertilizers, Fertilization, Cations, Absorption, Wheat,
Nitrogen, Potassium, Calcium, Zinc, Magnesium, Manganese,
Additions of small amounts of NH4 to adequate (,-)N03 culture have been shown to
increase crop yield and total N content, and to decrease the plant's content of
metal cations. The magnitudes of these effects can be appreciable. Accordingly,
experiments were done to elucidate their mechanisms, and to evaluate their roles
in crop production. Wheat was grown in the greenhouse in dilute constant-composi-
tion cultures that supplied, in factorial combination, three levels of NH4 with
four levels of either K, Ca, Mg, Mn, or Zn, Intake of mineral cations increased
with the concentration of the ion in solution and was decreased by added NH4.
77:03F-033
SUGAR CANE GROWTH IN RESPONSE TO MULCH AND FERTILIZER ON SALINE-ALKALI SUBSOILS,
Eavis, B.W., and Cumberbatch, E.R.St.J.
Ministry of Overseas Development, Department of Soil Physics, United Kingdom.
Agronomy Journal, Vol. 69, No. 5, p 839-842, September-October, 1977, 2 fig,
2 tab, 8 ref.
Descriptors: Mulches, Sugar cane, Crop response, Crop production, Fertilizers,
Fertilization, Nutrients, Salinity, Subsoils, Leaching, Land reclamation.
In many parts of the world where salinity or alkalinity limit crop yields, leaching
is impracticable. In Barbados saline-alkali subsoils remained unproductive six
years after they were exposed during earth-moving operations. The objective of
this study was to devise agronomic techniques to restore these lands to sugar cane
production. The effects of mulching and N-K fertilization were studied. Factorial
field experiments in which bare plots and plots mulched .with cut grass were treated
with fertilizer at three rates were carried out at two locations (sandy clay
and clay soil, respectively) . Sugar cane tillers and soil moisture contents were
measured weekly, and root development fortnightly. After 9 months of growth,
bare plots failed to produce any marketable yield in contrast to mulched plots
which gave up tcr 53 metric tons/ha (sandy clay) and 118 tons/ha (clay), There
were no responses to fertilizer rate on bare land, but on mulched land 1,2 times
(sandy clay) and 2.2 times (clay), more yield resulted from the high compared with
the low fertilizer rate.
77:03F-034
GROWTH AND YIELD OF SPRING WHEAT AS INFLUENCED BY SHELTER AND SOIL WATER,
Frank, A.B., Harris, D.G., and Willis, W.O.
Northern Great Plains Research Center, Department of Plant Science, Mandan,
North Dakota 58554.
Agronomy Journal, Vol. 69, No. 6, p 903-906, November-December, 1977. 1 fig,
6 tab, 20 ref.
Descriptors: Windbreaks, Wheat, Irrigation, Irrigation effects, Crop production,
Crop response, Soil water, Wind velocity, Leaves.
In the Northern Great Plains, windbreaks have historically been used to protect
crops and soils from winds, but data on the effects of windbreaks on growth and
yield of small grains is limited. "Waldron" wheat was grown on Parshall fine
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sandy loam with and without shelter (slat-fence enclosures), both with and with-
out irrigation, to determine the effects of soil water and shelter on wheat growth
and yield. In 1973 and 1974, plant height, tiller production, leaf area index,
specific leaf weight, and dry matter were measured at tillering, heading, and grain-
filling growth stages. Also, grain yield, kernel weight, number of heads, straw
yield, and plant height were measured at crop maturity.
77:03F-035
PLANT WATER RELATIONSHIPS OF SPRING WHEAT AS INFLUENCED BY SHELTER AND SOIL WATER,
Frank, A.B., Harris, D.G., and Willis, W.O,
Northern Great Plains Research Center, Department of Plant Science, Mandan, North
Dakota 58554.
Agronomy Journal, Vol. 69, No. 6, p 906-910, November-December, 1977. 6 fig, 1
tab, 19 ref.
Descriptors: Micro environment, Windbreaks, Wheat, Irrigation, Irrigation effects,
Crop production, Crop response, Soil water, Wind velocity, Leaves.
Field windbreaks have been planted primarily for soil erosion control; subsequently,
research has shown that windbreaks have an effect on microclimate and on growth
and yield of crops. Other research has shown that plant water relations respond
to changes in microclimate. The present work was undertaken to determine the ef-
fect of microclimate changes induced by a slat-fence windbreak on the plant water
relations of field-grown wheat. Slat-fence barriers were used as windbreaks for
studying effects of shelter-modified microclimate on plant water relations of
"Waldron" spring wheat, grown on Parshall fine sandy loam under irrigated and dry-
land soil water regimes. Data were collected on leaf water potential, xylem water
potential, stomatal diffusion resistance, canopy temperature, soil water potential,
soil water extraction, and grain yield,
77:03F-036
TILLAGE EFFECTS ON WINTER WHEAT PRODUCTION WHERE THE IRRIGATED AND DRYLAND CROPS
ARE ALTERNATED,
Unger, P.W.
United States Department of Agriculture, Southwestern Great Plains Research Center,
Bushland, Texas 79012.
Agronomy Journal, Vol. 69, No. 6, p 944-950, November-December, 1977. 2 fig, 5
tab, 11 ref, 3 equ.
Descriptors: Wheat, Irrigation, Irrigation effects, Crop production, Cultivation,
Crop response, Soil water, Soil moisture, Irrigation efficiency, Dry farming,
While adequately irrigated winter wheat yields are relatively high, dryland wheat
yields in the southern Great Plains are only about 700 kg/ha with continuous
cropping and about 1,000 kg/ha on a harvested area basis after fallow. This study
was conducted to determine if yields could be increased where irrigated and dry-
land wheat crops are alternated on the same plots. Tillage effects were also
studied.
77:03F-037
THE DEPENDENCE OF IRRIGATION REQUIREMENTS ON WATER-TABLE DEPTH IN DRAINED LANDS,
Nikolski, Y.N.
Moscow Institute of Hydromelioration, 19 Pryanishnikova Str., Moscow, Union of
Soviet Socialist Republics.
Agricultural Water Management, Vol. 1, No, 2, p 191-196, September 1977. 3 fig,
9 ref, 9 equ.
Descriptors: Drainage, Drainage effects, Irrigation, Irrigation effects, Water
table, Crop production, Evapotranspiration, Crop response.
The amount of irrigation water required to maintain an optimal average water con-
tent in the root zone for maximum crop yield is dependent on the water-table
depth as well as on evapotranspiration. An approximate expression is derived in
terms of soil constants for the vertical soil water flux, which may be directed
upwards or downwards, above the water table. This has been used in a water-balance
equation in order to estimate the irrigation requirement. Satisfactory agreement
is found between results calculated using this theoretical relationship and
published experimental work.
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77:03F-038
EVAPORATION IN HIGH LATITUDES,
Rouse, W.R., Mills, P.P., and Steward, R.B.
McMaster University, Department of Geography, Hamilton, Ontario, Canada.
Water Resources Research, Vol. 13, No. 6, p 909-914, December 1977 5 fia
3 tab, 9 ref, 7 equ. *
Descriptors: Model studies, Temperature, Evaporation, Latitudinal studies.
A simplified form of the equilibrium model of evaporation predicts evaporation
from six subarctic and tundra surfaces with an accuracy of 8%. Input data to
the model are net radiation, screen air temperature, and an evaporability fac-
tor characteristic of the surface. The radiation and energy balances of the
six surfaces are compared.
77:03F-039
ROW SPACING AND DIRECTION EFFECTS ON WATER UPTAKE CHARACTERISTICS OF PEANUTS,
Chin Choy, E.W., Stone, J.F., and Garton, J.E.
Oklahoma State University, Stillwater, Oklahoma 74074.
Soil Science Society of America Journal, Vol. 41, No. 2, p 428-432, March-
April, 1977. 5 fig, 2 tab, 14 ref.
Descriptors: Evapotranspiration, Peanuts, Crop response, Crop production.
Peanuts grown in 30-cm wide, north-south rows, lost less water to evapotranspiration
than those grown in 90-cm rows or than east-west rows of these spacings. Plants
grown in 90-cm wide, north-south rows tended to have the highest water losses.
The reason for this phenomenon was not determined, although there is reason to
believe net radiation is lower in narrow rows than wide. Yield of peanuts was
enhanced by the narrow rows and no orientation effect on yield was noted. Thus,
water-use efficiency was increased by both yield effect and water conservation
effect. Peanut quality was the same for all treatments. There is no reason to
believe that the water conserving effect is unique to peanuts. Research on
other crops in similar geometries is to be encouraged,
77:03F-040
THE BROWN-ROSENBERG RESISTANCE MODEL OF CROP EVAPOTRANSPIRATION MODIFIED TESTS
IN AN IRRIGATED SORGHUM FIELD,
Verma, S.B., and Rosenberg, N.J.
Nebraska University, Agricultural Meteorology Section, Department of Agricultural
Engineering, Institute of Agriculture and Natural Resources, Lincoln, Nebraska
68583.
Agronomy Journal, Vol. 69, No. 2, p 332-335, March-April, 1977. 3 fig, 2 tab,
16 ref, 6 equ.
Descriptors: Model studies, Evapotranspiration, Crop production,. Irrigation,
Sorghum, Temperatures.
The Brown-Rosenberg resistance model was modified to simplify its calculation
and increase its usefulness for estimating evapotranspiration. The model re-
quires inputs of net radiation, air temperature, and vapor pressure and canopy
and boundary layer resistance. The first three of these parameters are mea-
sured. In the modified version canopy resistance is estimated from a functional
dependence on irradiance. The boundary layer resistance is estimated from a
functional dependence on windspeed. The modification was tested in an irrigated
sorghum field at Mead, Nebraska. The model predictions generally agreed to
within 10% on both an hourly and daily basis, with direct lysimetric and Bowen
ratio-energy balance measurements of evapotranspiration from the sorghum,
77:03F-041
INFLUENCE OF CONSERVATION-TILLAGE ENVIRONMENTS ON GROWTH AND PRODUCTIVITY OF CORN,
Mock, J.J., and Erbach, D.C.
Iowa State University, Department of Agronomy, Ames, Iowa.
Agronomy Journal, Vol. 69, No. 3, p 337-340, May-June, 1977. 2 fig, 6 tab, 13 ref.
135
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Descriptors: Corn, Crop production, Crop response, Soils, Soil investigations,
Soil temperatures.
Research on growth responses of corn to environmental conditions associated with
conservation-tillage systems has not been extensively conducted. Therefore,
the objectives of this study were to evaluate effects of various tillage systems
(fall moldboard plow, till-plant, no-till ridge with and without previous-crop
residue) and early planting on growth and productivity of several corn genotypes
(including two heterogeneous breeding populations that were improved for cold
tolerance by recurrent selection). The experiment was conducted for 2 years on
a loam soil, and planting dates were April 1, 1974, and April 30, 1975. Conser-
vation-tillage systems were associated with lower midafternoon soil temperatures
during the early growing season and more variability in depth of seed placement.
Also, seedling and juvenile plant growth, final plant densities, and grain yields
were lower in conservation-tillage systems. These differences were accentuated
in the early planting environment of the 1974 experiment. With a relatively
normal planting date and equal final plant densities (the environment of the
1975 experiment), grain yields were not affected by tillage treatment. There was
no interaction between tillage method and corn genotype. In the central United
States Corn Belt, therefore, optimum corn grain yields in conservation-tillage
environments will be obtained by the use of planters that assure uniform seed
depth and genotypes that display vigorous plant growth and development.
77:03F-042
ONION-SEED YIELD AND QUALITY AS AFFECTED BY IRRIGATION MANAGEMENT,
Brown, M.J., Wright, J.L,, and Kohl, R,A.
Snake River Conservation Research Center, Kimberly, Idaho 83341,
Agronomy Journal, Vol. 69, No. 3, p 369-372, May-June, 1977. 1 fig, 2 tab, 15 ref.
Descriptors: Onions, Crop production, Crop response, Irrigation, Irrigation
effects, Irrigation practices, Soil moisture, Soil water, Idaho, Furrow irrigation,
Tensiometers, Germination.
The effects of soil moisture, sprinkler irrigation, and misting on hybrid onion-
seed production were evaluated at Kimberly, Idaho, Sprinkling and misting treat-
ments were included to determine if sprinkler irrigation could be used for onion-
seed production, and if evaporative cooling (misting) would alleviate the scalding
of umbels at excessively high temperatures. Results showed that reasonable
onion-seed yields could be obtained with sprinkler irrigation in spite of antici-
pated adverse effects on pollination. In areas with high daytime temperatures,
misting could be used to cool the umbels, as much as 15 C for about 20 min.f
although it does not seem necessary for the low 32 to 35 C daytime temperatures
at Kimberly. The highest onion-seed yields were obtained with the furrow-irrigation
treatment where water was applied when tensiometers at 20-cm depth read about
0.5 bar soil moisture tension (furrow adequate).
77:03F-043
COMPREHENSIVE NITROGEN FERTILIZER MANAGEMENT MODEL FOR WINTER WHEAT,
Jackson, G.D., and Sims, J.R.
Montana State University, Montana Cooperative Service, Bozeman, Montana 59715.
Agronomy Journal, Vol. 69, No. 3, p 373-377, May-June, 1977. 8 tab, 24 ref.
Descriptors: Nitrogen, Fertilizers, Fertilization, Model studies, Wheat, Montana,
Soil properties. Climates, Crop production.
Systems for predicting fertilizer N rates on dryland winter wheat in Montana have
needed refinement for several years. The objective of this study was to develop
a comprehensive N fertilizer management model for dryland winter wheat based on
soil properties and climatic factors. Data for multiple regression analysis were
gathered from 47 locations representing 4 growing seasons. A stepwise multiple
linear regression technique was used to generate equations for predicting optimum
grain yield, grain protein content at optimum yield levels, N fertilizer rate
needed to achieve optimum yield, post-harvest soil N03(-)N in surface 30 cm of
soil, and grain yield and protein content without N fertilization.
136
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77:03F-044
PEANUT SEED GERMINATION AS RELATED TO SOIL WATER REGIME DURING POD DEVELOPMENT,
Pallas, J.E. Jr., Stansell, J.R., and Bruce, R.R.
United States Department of Agriculture, Agricultural Research Service,
Watkinsville, Georgia 31794.
Agronomy Journal, Vol. 69, No. 3, p 381-383, May-June, 1977. 2 tab, 7 ref.
Descriptors: Crop production, Crop response, Peanuts, Germination, Soil moisture,
Soil water. Irrigation, Irrigation practices.
The problem of poor peanut seed germination has appeared to follow exceptionally
dry years in Georgia; consequently, the interaction of soil water availability
during the growing season and subsequent seed germination were studied. These
results are a composite of four years of study under controlled rainfall shelters
on Tifton loamy sand, a member of the fine-loamy, siliceous, thermic Plinthic
Paleudults, at six soil water levels. Soil water levels involved irrigation at
specified soil water tensions in surface 30 or 60 cm. Soil water tension ranged
from + 0.2 to greater than 15 bar. Good germination of all varieties was
obtained when the average soil water tension in the surface 30 cm was maintained
at less than 0.6 bars. On the other hand, allowing "Florigiant" to reach a soil
water tension greater than 15 bars during the growing season lowered its per-
centage of sound mature kernels 34 percent.
77:03F-045
NITROGEN AND CHLORIDE UPTAKE BY IRRIGATED RUSSET BURBANK POTATOES,
Saffigna, P.G., and Keeney, D.R.
Wisconsin University, Department of Soil Science, Madison, Wisconsin 53706.
Agronomy Journal, Vol. 69, No. 2, p 258-264, March-April, 1977. 1 fig, 7 tab,
20 ref.
Descriptors: Potatoes, Crop production, Wisconsin, Nitrogen, Chlorides, Nutrients,
Fertilizers, Fertilization, Irrigation, Leaching.
Potato production has become a major agricultural enterprise in the central sand
plain of Wisconsin. However, little information is available on the effects of
irrigation and fertilization practices on dry matter and N accumulation. This
field study was established to determine the effect of reducing irrigation and
fertilizer N on the dry matter, and the N and Cl in potatoes grown .'.on a Plainfield
loamy sand. Two basic treatments were used. The conventional treatment approxi-
mated current recommendations for irrigated potatoes and received 260 kg N/ha (as
NH4N03) in four applications and 45 cm irrigation as 2.4 cm applications every 5
days. The improved treatment was intended to minimize leaching of N03(-)N. It
received 170 kg N/ha in 10 applications (one as S-coated urea and nine as NH4N03)
and 27.0 cm irrigation as 1.0 cm applications every 3 days. Chloride (as KC1)
accompanied N on a 1:1 weight basis. Plants were sampled weekly and analyzed for
dry matter, total N, N03(-)N, and Cl.
77:03F-046
INFLUENCE OF THREE SOIL-WATER REGIMES ON ROOT POROSITY AND GROWTH OF FOUR RICE
VARIETIES,
Das, O.K., and Jat, R.L.
Indian Agricultural Research Institute, National Bureau of Soil Survey and Land
Dse Planning, New Delhi, India.
Agronomy Journal, Vol. 69, No. 2, p 197-200, March-April, 1977. 4 fig., .2 tab,
20 ref.
Descriptors: Soil moisture, Soil water, Root systems. Root development, Rice,
Saturated soils. Crop production.
A better understanding of the growth response of rice to waterlogged soil conditions
is desirable. The objective of this study was to measure the influence of soil
water regime on root porosity, growth, and nutrient content of four varieties of
rice at various dates after transplanting. Four rice varieties were grown under
three soil water regimes (continuous flooding, alternate flooding, and no flooding)
in a greenhouse on a clay loam soil. Root porosity, growth of plants and nutrient
(N, P, K, Ca, and Mg) content of shoots were determined at four different plant
ages (30, 60, 85, and 110 days after transplanting). Root porosity was greatest
137
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in plants grown with continuous flooding. Porosity of roots in all four varieties
reached maximum values between 30 and 60 days and then started to decline. Padma
and BC6 had higher root porosities than IRS and IR22. High root porosity was
associated with greater root length, increased dry weight of roots and shoots,
and higher nutrient content in shoots.
77:03F-047
YIELDS AND NUTRIENT ACCUMULATION BY DETERMINATE SOYBEANS, AS AFFECTED BY APPLIED
NUTRIENTS,
Terman, G.L.
National Fertilizer Development Center, Soils and Fertilizer Research Branch,
Tennessee Valley Authority, Muscle Shoals, Alabama 35660.
Agronomy Journal, Vol. 69, No. 2, p 234-238, March-April, 1977. 2 fig, 5 tab,
12 ref.
Descriptors: Fertilizers, Fertilization, Soybeans, Nutrients, Crop response,
Crop production.
Most published results with southern determinate soybeans are concerned with only
a single fertilizer treatment and/or one or two sampling dates. Consequently,
field experiments were conducted to determine effects of applied N and K on dry
matter yields, nutrient concentrations, and nutrient uptake at several sampling
dates and on final grain yields. Rates of 0, 86, and 172 kg of applied K/ha and
0 and 70 kg of N were compared in a field experiment on Sango sil in 1973 and
K rates of 0, 75, and 150 kg/ha in 1974. Marked responses to applied K were
obtained. Maximum dry matter yields and nutrient uptake occurred during the
early pod filling stage of growth. Dry matter yields then declined as a result
of greater loss of leaf and petiole drop than of increase in grain filling. Con-
centrations of K in leaves, topgrowth, and grain increased with amount of applied
K, but top trifoliate leaf blade concentrations were lower than some published
recommended levels for high yields. Marked reciprocal relationships occurred
among concentrations of K and Ca or Mg in top trifoliate leaves and topgrowth.
Several combinations of N, P, K, and S foliar- and soil-applied during pod
filling were also compared in 1976 pot experiment on Sango sil. Grain yields
and concentrations of each applied nutrient were increased in leaves and grain.
Pod numbers were highly correlated with grain yields.
77:03F-048
CONSERVATION TILLAGE IN THE PACIFIC NORTHWEST,
Papendick, R.I., and Miller, D.E.
United States Department of Agriculture, Agricultural Research Service, Pullman,
Washington 99164.
Journal of Soil and Water Conservation, Vol. 32, No. 1, p 49-56, January-February,
1977. 4 fig, 1 tab, 49 ref.
Descriptors: Crop production, Soil erosion, Water conservation, Runoff, Soil
surface, Soil properties, Soil management, Land resources, Agriculture.
Despite years of research and development, tillage and cropping practices to con-
serve soil and water in the Pacific Northwest have not completely achieved the
goals of efficient water use and soil protection. Precipitation and irrigation
water still run off, and soil losses remain high. In the Palouse Region, for
example, where the moldboard plow is widely used, erosion is as great as anywhere
in the United States. There is a trend in many areas to reduced tillage and
surface residue systems.
77:03F-049
DRAINAGE CONTROL TO DIMINISH NITRATE LOSS FROM AGRICULTURAL FIELDS,
Gilliam, J.W., Skaggs, R.W., and Weed, S.B.
North Carolina State University, Department of Soil Science, Raleigh, North
Carolina.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, North Carolina State University, Raleigh, North
Carolina, p. 1-16. 8 fig, 11 ref.
Descriptors: Drainage, Nitrates, Agriculture, Drainage effects. Drainage water,
Drainage systems, Nutrients, Nitrogen.
138
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Flashboard riser type water level control structures were installed in four tile
mains or outlet ditches at two locations. Under controlled drainage conditions,
there was a large decrease in both nitrate and drainage water lost through the
artificial drainage systems. The effect on nitrate ultimately entering surface
waters, however, is believed to depend on soil type.
77:03F-050
COMPUTERIZED IRRIGATION SCHEDULING USING NEUTRON PROBES,
Buchheim, J.F., and Ploss, L.F.
United States Department of the Interior, Bureau of Reclamation, Engineering and
Research Center, Denver, Colorado 80225.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, North Carolina State University, Raleigh, North
Carolina, p. 1-12. 5 fig, 3 ref, 6 equ.
Descriptors: Scheduling, Soil moisture, Soil water, Computer programs. Irrigation,
Irrigation practices.
The development and evaluation of computer-supported irrigation scheduling are
discussed. The use of neutron probes is being initiated in several areas to
enhance the scheduling procedure. The results of one year of operation using
these procedures in many areas including an analysis on an irrigation district
confirmed the practical use of neutron probes.
77:03F-051
CONSERVATION TILLAGE IN THE WESTERN CORN BELT,
Amemiya, M.
Iowa State University, Department of Agronomy, Ames, Iowa 50011.
Journal of Soil and Water Conservation, Vol. 32, No. 1, p 29-36, January-February,
1977. 8 tab, 59 ref.
Descriptors: Crop production, Agriculture, Soil erosion, Soil management, Soil
conservation, Water quality, Erosion.
Fertile soils and favorable climate make the western Corn Belt-Iowa, Minnesota,
Missouri, and the humid areas of eastern Nebraska and eastern South Dakota-one of
the world's outstanding grain-producing regions. For the western Corn Belt to
continue to use its productive soils and favorable climate to help meet domestic
and world agricultural needs will depend on how prudently the land resource is
used. Soil erosion is the dominant limitation to agriculture on at least 30 per-
cent of the region's cropland, and this cropland's potential contribution to
watershed sediment yield is very high.
77:03F-052
SOIL CONSERVATION ON AGRICULTURAL LAND: THE CHALLENGE AHEAD,
Davis, R.M.
United States Department of Agriculture, Soil Conservation Service, Washington,
D.C. 20250.
Journal of Soil and Water Conservation, Vol. 32, No. 1, p 5-8, January-February,
1977- 5 ref.
Descriptors: Agriculture, Soil conservation, Soil management. Crop production,
Erosion, Soil erosion, Water quality-
Agriculture is a dynamic industry. Its technology and economics change constantly.
Within this dynamic framework, soil conservationists, for more than four decades
now, have tried to keep one objective clearly in view: To bring about improved
soil and water management through a voluntary, cooperative program with conser-
vation districts and land users. Today, soil conservationists still find themselves
confronted by change and challenge.
77:03F-053
FUTURE USE OF AGRICULTURAL LAND FOR NONAGRICULTURAL PURPOSES,
Spaulding, B.W., and Heady, E.G.
Arkansas University, Department of Agricultural Economics and Rural Sociology,
139
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Fayetteville, Arkansas 72701.
Journal of Soil and Water Conservation, Vol. 32, No. 2, p 88-93, March-April,
1977. 2 fig, 6 tab, 16 ref.
Descriptors: Agriculture, Urbanization, Land use, Land development, Land
resources, Land management, Land classification.
A procedure to estimate the acreage of agricultural land needed for nonagricultural
purposes in the continental United States to the year 2000 was developed. The
acreage to be converted by the turn of the century represents a 2.2 percent re-
duction in the nation's existing agricultural land base. Overall, our nation's
productive capacity in agriculture will not be impaired significantly by this loss
of land to nonagricultural purposes. However, the impacts will likely be signifi-
cant at state and local levels.
77:03F-054
WHEAT CANOPY TEMPERATURE: A PRACTICAL TOOL FOR EVALUATING WATER REQUIREMENTS,
Jackson, R.D., Reginato, R.J., and Idso, S.B.
United States Water Conservation Laboratory, United States Department of Agricul-
ture, Agricultural Research Service, Phoenix, Arizona 85040.
Water Resources Research, Vol. 13, No. 3, p 651-656, June 1977. 6 fig, 27 ref.
Descriptors: Wheat, Temperature, Crop response. Irrigation, Soil water. Soil
moisture, Lysimeters, Evapotranspiration, Irrigation efficiency.
Canopy temperatures were measured on durum wheat grown in six differentially
irrigated plots. Soil water content was measured by using a neutron-scattering
technique at two locations within each plot. Water contents, in 20-cm increments
to 160 cm, were determined two to five times per week. using a sliding cubic
smoothing technique, we calculated daily water contents and thus water depletion
rates for the entire growing season. Canopy temperatures were measured daily
between 1330 and 1440 hours. Air temperatures measured at 150 cm above the soil
surface were subtracted from the canopy temperatures to form the difference Tc -
Ta. The summation of Tc - Ta over time yielded a factor termed the "stress degree
day" (SDD). The SDD concept shows promise as an indicator for determining the
times and amounts of irrigations. An expression relating evapotranspiration (ET)
to net radiation and Tc - Ta was simplified and tested by using ET measurements
with a lysimeter. The expression was used to predict water use by wheat in the
six plots. Predicted ET and measured water used agreed reasonably well. The
expression may be useful in determining amounts of irrigation water to apply.
77:03F-055
PHOTOSYNTHESIS, TRANSPIRATION, AND LEAF ELONGATION IN CORN SEEDLINGS AT SUBOPTIMAL
SOIL TEMPERATURES,
Barlow, E.W.R., Boersma, L., and Young, J.L.
MacQuarie University, School of Biological Sciences, Sydney, Australia.
Agronomy Journal, Vol. 69, No. 1, p 95-100, January-February, 1977. 7 fig, 33 ref.
Descriptors: Plant physiology. Crop response. Soil temperatures, Photosynthesis,
Corn, Crop production, Temperature.
The physiology of plant response to low soil temperatures is not well understood.
Laboratory studies were conducted to examine the relative sensitivities of rates
of leaf elongation, net photosynthesis, and transpiration and the leaf water poten-
tial of corn seedlings to decreasing temperature. These parameters were simul-
taneously monitored, as the soil temperature was decreased from 28 to 10 C at about
4 C increments. The different soil temperatures were imposed during a 10-hour
period on 14-day-old plants with seven exposed leaves growing at a 27.5 C air
temperature, a 55% relative humidity, and a light intensity of 753 muE/m2/sec.
Any decrease of the soil temperature below 28 C decreased the leaf elongation rate.
This was attributed to restricted water uptake which lowered the plant water po-
tential and to the temperature decrease of the shoot apical meristem region. Leaf
elongation ceased at the plant water potential of -9 bars due to decline of leaf
turgor pressure.
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77:03F-056
NITROGEN, CHLORIDE, AND WATER BALANCE WITH IRRIGATED RUSSET BURBANK POTATOES IN
A SANDY SOIL,
Saffigna, P.G., Keeney, D.R., and Tanner, C.B.
Queensland Wheat Research Institute, 13 Holberton Street, Toowoomba, Queensland
43500, Australia.
Agronomy Journal, Vol. 69, No. 2, p 251-257, March-April, 1977. 3 fig, 6 tab
22 ref.
Descriptors: Nitrogen, Chlorides, Irrigation, Irrigation effects, Potatoes,
Sands, Sprinkler irrigation, Fertilizers, Fertilization, Groundwater, Wisconsin,
Lysimeters, Irrigation efficiency.
Large applications of sprinkler irrigation and N fertilizer have been implicated
in causing nitrate contamination of groundwater in central Wisconsin. Field and
lysimeter experiments were established in 1972 and 1973 on the Plainsfield loamy
sand to determine the effect of reducing the amount of sprinkler-irrigation and
fertilizer N on potato tuber yields and on the field water and N balance. Two
main treatments were used. The conventional (CON) treatment received irrigation
water and N fertilizer according to current recommendations. The improved (IMP)
treatment received less irrigation water than the CON treatment in both years.
A satisfactory mass balance of water, N and CI for potatoes grown in the lysi-
meters was obtained. Drainage accounted for considerable amounts of the water,-
N, and CI outputs with nearly all of the remainder going to evapotranspiration
and plant uptake. The carefully managed IMP treatment decreased N03(-)N leaching
from 200 to 120 kg N/ha and lowered the overall average N03(-)N concentration of
the leachate from 23 to 16 mg N03 (-) N/liter. However,, the additional costs
required to effect a small savings in N fertilizer is probably not justified.
77:03F-057
SELECTED IRRIGATION RETURN FLOW QUALITY ABSTRACTS, 1975,
Skogerboe, G.V., Smith, S.W., and Walker, W.R.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Publication No. EPA-600/2-77-094, May 1977. 249 p.
Descriptors: Fertilizers, Irrigated land, Irrigation systems, Irrigation water,
Nitrates, Phosphates, Return flow, Salinity, Water pollution effects. Water
pollution sources, Water quality control.
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 publi-
cations printed in 1970 and 1971, the third annual issue covers calendar years
1972 and 1973, and the fourth annual issue covers literature published in 1974.
This annual issue lists publications printed in 1975. This report was submitted
in fulfillment of Grant Number R-800426 under the sponsorship of the Office of
Research and Development, Environmental Protection Agency-
77:03F-058
SUNFLOWER YIELD AND WATER USE AS INFLUENCED BY PLANTING DATE, POPULATION, AND
ROW SPACING,
Alessi, J. , Power, J.F., and Zimmerman, D.C.
United States Department of Agriculture, Northern Great Plains Research Center,
Mandan, North Dakota.
Agronomy Journal, Vol. 69, No. 3, p 465-469, May-June, 1977. 4 fig, 4 tab, 8 ref.
Descriptors: Crop response, Crop production, Temperature, Agriculture, North
Dakota.
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Sunflower has only recently been grown commercially as an oilseed crop in the drier
regions of the Northern Great Plains. This study was conducted to acquire pre-
liminary information on seed yield, oil concentration, and water use for oil-type
sunflower as affected by planting date, plant population, and row spacing; and to
obtain an indication how these results were affected by yearly variation in pre-
cipitation and air temperature.
77:03F-059
SHORT-TERM SPRINKLER PATTERNS BY DYE-CONCENTRATION,
McMaster, G.M.
Idaho University, Department of Agricultural Engineering, Aberdeen, Idaho 83210.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-5.
2 fig, 6 ref.
Descriptors: Sampling, Sprinklers, Sprinkler irrigation, Irrigation, Irrigation
effects. Irrigation efficiency.
A procedure was tested to determine the sprinkler head pattern resulting from a
few revolutions of the head. A fluorescent dye, detectable at low concentration
in water, was injected upstream from a sprinkler head. Precipitation collectors
were charged with a measured volume of water. The precipitation rate on each
collector was determined by measuring dye concentration with a fluorometer. Tests
of several time durations were conducted and compared.
77:03F-060
ANALYSIS OF THE DIMENSIONLESS LINEAR CUMULATIVE FREQUENCY DISTRIBUTION OF WATER
DEPTHS UNDER SPRINKLER IRRIGATION,
Karmeli, D., and Peri, G.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-36.
12 fig, 2 tab, 4 ref, 53 equ.
Descriptors: Sprinkler irrigation, Irrigation, Model studies, Irrigation effi-
ciency.- Irrigation effects.
The linear regression model is used to describe sprinkler distribution patterns.
The linear fit is found to approximate the distribution very well in a wide range
of experimental data. The use of the model allows for additional information
regarding irrigation quality parameters. Associated with the linear regression,
a new coefficient, UCL, is suggested for practical use.
77:03F-061
ALLOCATION PROCEDURE OF FARM RESOURCES IN RELATION TO SOME IRRIGATION QUALITY
PARAMETERS,
Karmeli, D.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina State University, p. 1-15.
1 fig, 3 tab, 5 ref.
Descriptors: Crop production. Agriculture, Irrigation, Irrigation effects, Irri-
gation systems, Irrigation efficiency, Water allocation.
Land, water, labor and capital are optimally allocated to crops on a farm, using
a procedure that also relates to irrigation frequency and level of improvement in
the irrigation system. The procedure is based on formulating outputs and expendi-
tures as well as the functions of irrigation frequencywater and yield. The
Generalized Geometric Programming is used to solve the objective function as non-
linear equations are involved.
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77:03F-062
MANAGEMENT OF IRRIGATION STREAM SIZE FOR IMPROVED RUNOFF WATER QUALITY,
Allen, R.G., Busch, J.R., Lewis, G.C., and Fitzsimmons, D.W.
Idaho University, Department of Agricultural Engineering, Moscow, Idaho.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December, 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-9.
6 fig, 1 tab, 8 ref, 1 equ.
Descriptors: Irrigation, Runoff, Water quality, Irrigation water. Furrow
irrigation, Erosion, Sediments, Nutrients, Irrigation efficiency.
A study of water quality changes between applied irrigation water and runoff for
two furrow irrigated 0.89 ha plots is reported. Furrow streams on one plot were
cutback to minimize runoff and erosion, and the second plot was used as a control.
Losses of sediment and nutrients from the cutback-irrigated plot were much less
than lost from the control, and the water-use efficiency was 73 percent versus
41 percent for the control.
77:03F-063
CANAL SEEPAGE REDUCTION BY SEDIMENT LADEN WATER,
Edling, R.J.
Nebraska University, Department of Agricultural Engineering, Lincoln Panhandle
Station, Scottsbluff, Nebraska.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-15.
3 fig, 3 tab, 4 ref.
Descriptors: Seepage, Canal seepage, Sediments, Sediment load, Economics.
The influence of artificially induced sediment laden water on Interstate Canal
seepage loss was studied. The Interstate Canal is the largest canal in the North
Platte project. Substantial seepage loss reduction due to sediment laden water
was realized in one of the four years studied. The practice of artificially in-
ducing sediment laden water to reduce seepage loss is"being threatened by environ-
mental and economical concerns.
77:03F-064
A LYSIMETER SYSTEM FOR WATER TABLE CONTROL,
Shih, S.F., Gascho, G.J., and Mishoe, J.W.
Florida University, Agricultural Research and Education Center, Belle Glade,
Florida.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-12.
4 fig, 2 tab, 13 ref.
Descriptors: Lysimeters, Water table, Sugarcane, Irrigation, Irrigation effects,
Crop production.
Lysimeters were constructed from plastic-lined, above-ground swimming pools in
order to control water tables at 30, 60, and 90 cm below the surface of muck soil
for sugarcane culture. Details of the construction and water table maintenance
data are included. The water tables were well maintained for a low installation
cost of about $20/sq m of soil surface area.
77:03F-065
COMPARISON OF SURFACE-DRAINED AND SUBSURFACE-DRAINED CLAYPAN SOILS,
Walker, P.N. . .
Illinois University, Department of Agricultural Engineering, Urgana, Illinois
61801.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-6.
5 fig, 1 tab, 3 ref.
Descriptors: Corn, Crop production, Drainage, Irrigation, Irrigation effects,
Drainage effects, Furrow irrigation, Sprinkler irrigation.
143
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Corn grown in claypan soil received ten different combinations of drainage and
irrigation treatments. One year's yield data indicate no major differences
between the drainage treatments or between sprinkler and furrow irrigation.
Irrigated plot yields average 9.3 tonnes/ha. Nonirrigated plot yields averaged
4.3 tonnes/ha.
77:03F-066
SOIL AND WATER CONSERVATION PRACTICES FOR POLLUTION CONTROL,
Walter, M.F., Steenhuis, T.S., and Haith, D.A.
Cornell University, Department of Agricultural Engineering, Ithaca, New York
14853.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p. 1-19.
6 tab, 42 ref.
Descriptors: Soil conservation, Water conservation, Water quality. Water quality
control. Pollution, Pollutants.
Policy concerning BMP's to control agricultural nonpoint source pollution has
yet to be developed. There has been a tendency to equate BMP's with soil and
water conservation practices. SWCP's must be capable of enhancing water quality
if they are to be used as BMP's. This paper discusses the effect of SWCP's on
water quality-
77:03F-067
DRIP IRRIGATION,
Shoji, K.
Scientific American, p 62-68, November 1977. 5 fig, 1 tab.
Descriptors: Irrigation, Irrigation systems, Irrigation efficiency, Crop
production, Soil water, Soil water movement, Water conservation, Saline water,
Salinity.
In this system plastic pipes laid on the surface of the ground deliver water to
plants drop by drop. The system reduces stress on the plant, conserves water and
works well with saline water.
77:03F-068
ENERGY AND IRRIGATION SYSTEM PLANNING,
Huinpherys, A.
Snake River Conservation Research, Agricultural Engineering Division, Kimberly,
Idaho.
Irrigation Age, Vol. 11, No. 7, p 74-75, April 1977. 2 tab.
Descriptors: Irrigation systems, Irrigation engineering, Irrigation practices,
Irrigation design, Economics.
Most irrigators are concerned with the spiraling costs and threatened shortages
of energy for irrigation pumping. Energy costs are expected to continue increasing
and, in some areas, limited energy supplies may restrict irrigation development.
Irrigation systems are normally based on a least cost design. With low energy
costs, for example, it has been more economical to use smaller pipes than would
be used for minimum-energy designs. Future systems may require a minimum-energy
design to minimize energy inputs. As energy costs increase, this also may be the
least cost design.
77:03F-069
NEUTRON PROBE PROMISING SCHEDULING TOOL,
Dronsfield, A.S.
Bureau of Reclamation, Irrigation Management services Branch, Lower Colorado
Region, Boulder City, Nevada.
Irrigation Age, Vol. 11, No. 8, p 38, May-June, 1977. 1 fig.
Descriptors: Soil water, Soil moisture, Crop production, Irrigation, Irrigation
efficiency, Irrigation practices.
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The success of the irrigation farmer has largely depended on his judgment of when
to irrigate and how much water to apply. His success has always been challenged
by the effectiveness with which he applied water to his crops. Proper irrigation
management has been, and today is, largely an "art." The Neutron Probe is now a
field tool and can be used to determine when to irrigate and how much water to
apply. It has been recognized as an excellent research instrument for deter-
mining soil moisture content.
77:03F-070
WORLD'S LARGEST SOLAR-POWERED IRRIGATION SYSTEM OPERATING IN ARIZONA: RISING
ENERGY COSTS CAUSE EXPLORATORY VENTURE,
Irrigation Journal, Vol. 27, No. 4, p 14-15, July-August, 1977-
Descriptors: Arizona, Irrigation systems, Irrigation practices, Solar radiation,
Pumping plants.
The world's largest solar-powered irrigation system was dedicated in late April
at Northwestern Mutual Life Insurance Company's Gila River Ranch, southwest of
Phoenix. The system, developed by the Columbus Laboratories of Battelle Memorial
Institute, includes a 50-horsepower pump capable of delivering up to 10,000 gallons
of irrigation water per minute at peak operation.
77:03F-071
IRRIGATED SOYBEANS: BIG YIELDS FROM A LITTLE TIMELY WATER,
Schleicher, J.
Irrigation Age, Vol. 11, No. 7, p 16, 18, 20, April 1977. 2 fig.
Descriptors: Soybeans, Crop production, Irrigation, Irrigation efficiency, Irri-
gation water, Crop response.
As irrigation presses eastward, Midwestern farmers are more and more interested in
adapting irrigation to their own crop production programs. One frequent comment:
"What about irrigating soybeans?" Surprisingly, soybean irrigation already has a
strong hold in the Midwest. In Nebraska last year, an estimated 200,000 acres of
soybeans were produced under irrigation. Some 120,000 acres of soybeans were grown
with supplemental water in Texas. Another 90,000 acres were irrigated in Missouri
in 1976, 35,000 acres in Kansas, and an estimated 17,000 acres in Oklahoma.
77:03F-072
INTERDISCIPLINARY MODELS OF WATER SYSTEMS,
Shahane, A.N.
Central and Southern Florida Flood Control District, Environmental Systems Engi-
neering Division, West Palm Beach, Florida 33402.
International Commission on Irrigation and Drainage Bulletin, Vol. 26, No. 1, p
58-69, January 1977. 1 fig, 35 ref.
Descriptors: Model studies, Simulation analysis, Water supply, Computer programs,
Computers, Mathematical studies, Water conservation. Water delivery, Water
resources.
Due to the complex structure of water systems, modern efforts are largely geared
to the multidisciplinary analysis of these water systems. The scope of this
paper is to present in a logical manner the various interdisciplinary concepts
and formulations involved in the modeling of the water system. The main rational
behind this effort is to broaden the isolated perspective by getting exposed to
the other equally important aspects of water systems. Based on the discussion
of the previous sections, it can be realized that the success of these modeling
efforts is dependent on the data base, computer capacity, the validity of assump-
tions, estimation procedure for rate coefficients or arbitrarily chosen weights
and finally the verification for the outcome. Since every situation is unique in
itself, the model building procedure varies significantly and thus its application
becomes an art rather than a science. With the understanding of these inter-
disciplinary interactions and their mathematical formulation coupled with necessary
weighing procedures, it is hoped that water systems can be adequately modeled to
include real-world complexities in the near future.
145
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77:03F-073
POLICY OF PRICING IRRIGATION WATER IN ENGLAND AND WALES,
Ministry of Agriculture, Great Britain.
Land Drainage Service, Ministry of Agriculture, Fisheries and Food, Great
Britain.
International Commission on Irrigation and Drainage, Vol. 26, No. 1, p 20, 30,
January 1977.
Descriptors: Irrigation water, Irrigation, Irrigation practices, Pricing, Water,
Water demand, Economics.
Irrigation of farm crops in England and Wales is supplementary to the natural
rainfall which can provide all the water required by the crops in many years,
this being particularly true in the wetter western areas. It is therefore
mainly used for high value crops such as early and main crop potatoes and in
market gardens. The driest area is South Eastern England, and it is estimated
that the frequency of irrigation to maintain easily available soil moisture at
all times between April and September is 20 years out of 20 years. Unlike many
countries, where irrigation is an absolute necessity to maintain crop growth,
there are no large irrigated areas dependent on a water supply system which
is controlled by governmental agencies or local irrigation boards. Since it is
the choice of each individual grower whether to use irrigation on the farm or
market garden, the areas of irrigated land are often quite small, and widely
separated from those of other irrigators. Consequently.- each user takes the
water from a variety of often widely spaced and differing ground and surface
water sources, or from the public water supply mains.
77:03F-074
RATIONALIZATION OF IRRIGATION RATES IN A DEVELOPING COUNTRY,
Gole, C.V., Amble, V.N., and Chopra, M.M.L.
Central Water Commission, Government of India, New Delhi, India.
International Commission on Irrigation and Drainage, Vol. 26, No. 1, p 31-40,
49, January 1977. 1 tab, 6 ref.
Descriptors: Irrigation water. Irrigation, Irrigation practices, Pricing, Water,
Water demands. Economics.
The problem of fixation of irrigation rate assumes particular importance in a
developing country like India where the State has to assume responsibility for the
large-scale supply of irrigation. The irrigation rate has then to be determined
balancing two opposing considerations. On the one hand, it is necessary to recover
the costs and even a share of the benefit received by the irrigator in the interest
of resource mobilization for further development as the benefit of irrigation
accrues only to a small section of the population. On the other hand, the producer
has to be provided the incentive for increasing production through greater utili-
zation of irrigation. The paper reviews the existing practices with regard to
irrigation rates in various States of India and some other countries and discusses
the principles for arriving at a rational structure of irrigation rates.
77:03F-075
GYPSUM BLOCKS, TENSIOMETERS RELIABLE SOIL MOISTURE MONITORS,
Irrigation Age, Vol. 11, No. 7, p 31, 40, 48, April 1977. 1 fig, 4 tab.
Descriptors: Tensiometers, Soil moisture, Soil water, Crop production, Irrigation,
Irrigation efficiency.
Two dependable, easy-to-use methods for irrigation scheduling are electrical re-
sistance blocks and tensiometers. Both systems will help conserve water and
increase yields. A brief run-down on each with suggestions on how to use them is
presented.
77:03F-076
SPRINKLER IRRIGATION PRACTICES AND WATER LOSSES:
FOR CONSERVATION,
Duble, R.L.
WATER SHORTAGES UNDERLINE NEED
146
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Texas A and M University, Agricultural Extension Service, College Station, Texas.
Irrigation Journal, Vol. 27, No, 2, p 16-17, 20, 46, March-April, 1977- 3 fig.
Descriptors: Sprinkler irrigation, Irrigation practices, Irrigation systems.
Water conservation, Water resources, Turf, Irrigation efficiency.
Having witnessed the effects of a water shortage in many sections of the
country during the summer of 1976, the value and need for conservation of water
can be appreciated. Since scientists forecast more extensive droughts throughout
the next decade, people must become more conscious of water use. In order for
there to be adequate water supplies for turf irrigation in the future, careful
management of water resources is necessary and must be implemented now.
77:03F-077
IRRIGATION IN WYOMING,
Brosz, D.J.
Wyoming University, Department of Engineering, Laramie, Wyoming.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 173-175, February 13-15, 1977-
Descriptors: Irrigation, Wyoming, Irrigation practices, Resources, Resource
development, Water, Water conservation.
Wyoming has the opportunity of finance, through minerals, its own water projects;
any size, without having to obtain money from the federal government. Now, state
funds made available for loans can be authorized for: (1) Reclamation of new
lands (irrigation); (2) Development of new water supplies for existing irrigated
land that is short of water supplies; (3) Construction of reservoirs, diversion
works, canals, pipelines, pumping stations, etc.; and (4) Development of groundwater.
77:03F-078
FREQUENT IRRIGATION MORE EFFICIENT,
Martin, W.W.
United States Department of Agriculture, Agricultural Research Service, Peoria,
Illinois.
Crops and Soils Magazine, Vol. 29, No. 5, p 10-12, February 1977. 3 fig.
Descriptors: Irrigation, Irrigation practices, Irrigation effects, Soil water,
Soil moisture. Fertilizers, Irrigation efficiency.
Frequent light irrigations on sandy soil save water and the energy to pump it and
also reduce the amount of fertilizer nitrogen moving below the reach of plant
roots as a potential groundwater pollutant.
77:03F-079
DRIP AND SPRINKLER IRRIGATION OF CARROTS AND ONIONS,
Melstad, J.D., and DeBoer, D.W.
Montana Department of Health and Environmental Sciences, Subdivision Bureau,
Montana.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p. 1-13. 1 fig, 6 tab, 8 ref.
Descriptors: Carrots, Onions, Sprinkler irrigation, Irrigation systems, Irri-
gation.
One carrot and two onion varieties were drip and sprinkler irrigated. Drip
yields were greater than sprinkler yields when equal gross amounts^of water^were
used. Drip onions and carrots were larger on the average than sprinkler onions
and carrots.
77:03F-080
NEMATICIDE DISTRIBUTION UNDER A DRIP EMITTER,
Garvey, P.M., and Chesness, J.L.
Georgia University, Department of Agricultural Engineering, Athens, Georgia.
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Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p. 1-16. 3 fig, 3 tab, 17 ref.
Descriptors: Nematocides, Soils, Soil properties, Irrigation, Irrigation
effects, Irrigation systems.
Distribution of nematicide in the soil when applied at different concentrations
through a drip irrigation emitter was studied. Thirty, eight hundred, and
fifteen hundred ppm concentrations were used and soil volumes exposed to lethal
concentrations of the nematicide were determined for each.
77:03F-081
PLANNING SYSTEMS TO MAXIMIZE QUALITY AND PROFIT,
Bean, E.L.
Irrigation Specialist, Lake Elsinore, California.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 67-69, February 13-15, 1977.
Descriptors: Irrigation, Irrigation practices, Irrigation design, Turf, Turf
grasses, Water conservation, Soils, Sprinkler irrigation. Irrigation systems.
Various design factors as related to irrigation systems are presented and dis-
cussed with particular emphasis on turf irrigation systems.
77:03F-082
SCHEDULING AND MONITORING IRRIGATION WITH INFRARED PHOTOGRAPHY,
Pitney, M.
Crop Protection, Incorporated, Umatilla, Oregon.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 176-177, February 13-15, 1977.
Descriptors: Scheduling, Irrigation, Irrigation practices, Soil moisture, Soil
water, Infrared radiation, Crop production, Crop response.
Aerial infrared photography was originally developed to detect camouflage during
the war. Today it is being used in agriculture to identify plants which are
under stress from disease/ moisture and nutrients. By interpretation of the
infrared reflectance, as recorded on film, it is possible to distinguish between
healthy and unhealthy foliage. The value of photography is in the early detection
of the stressed plants. The photography also makes the application of corrective
measures quick and efficient.
77:03F-083
GROWTH OF SPRINKLER SIX TIMES FASTER THAN FURROW IRRIGATION,
Irrigation Age, Vol. 11, No. 5, p 28, 48, February 1977. 1 fig, 1 tab.
Descriptors: Sprinkler irrigation, Furrow irrigation, Irrigation methods. Irri-
gation practices, Irrigation systems.
There has recently been a substantial increase in the level of prices for grains
both in world markets and in the United States. Sprinkler irrigation accounts
for by far the major portion of the growth in irrigated areas in the United
States. Between 1974 and 1975 the rate of growth of sprinkler irrigation was
6.2 times the rate of growth of gravity irrigation. The rapid increase in center
pivot irrigation accounts for a major proportion of this growth in sprinkler
irrigation.
148
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77:03F-084
SOLAR IRRIGATION SYSTEM BEGINS OPERATING IN NEBRASKA,
Irrigation Journal, Vol. 27, No. 5, p 37, September-October, 1977. 1 fig.
Descriptors: Irrigation, Irrigation practices. Irrigation systems. Solar radia-
tion, Nebraska,
One of this country's first crop irrigation systems to be powered by solar energy,
began operating the end of July in Mead, Nebraska, after dedication ceremonies
lead by Nebraska Governor J. James Exon. The solar unit, designed by the Massa-
chusetts Institute of Technology's Lincoln Laboratory, will use approximately
120,000 solar cells to convert the sun's rays into electricity. The unit drives
a ten horsepower pump to irrigate 80 acres of corn and soybeans in the summer.
In addition to irrigation, the solar powered system will be used during the fall
and winter to dry crops that will be harvested from the field.
77:03F-085
WATER'S KEY TO PROFITABLE ALFALFA SEED PRODUCTION,
Irrigation Age, Vol. 12, No. 2, p 38, 40, October 1977. 3 fig.
Descriptors: Alfalfa, Crop production, Irrigation, Irrigation efficiency, Irriga-
tion practices, Washington, Seeds,
Water for irrigation, or the lack of it at critical times in the growing season,
has turned the western end of Walla Walla County, .Washington into one of the
nation's prime locations for alfalfa seed production. Stan Wagoner of Touchet,
who raises 250 acres of seed each year says irrigation water for the area comes
from the Blue Mountains. Unfortunately, wate-r flow from the mountains stops the
first of June and doesn't resume until September, This limits the growing of row
crops which require summer-long irrigation. But for alfalfa seed, the availability
of water is suitable.
77:03F-086
EVAPORATIVE COOLING OF PEACH TREES TO BREAK REST AND DELAY BLOOM,
Chesness, J.L., Hendershott, C.H,, and Couvillon, G.A,
Georgia University, Department of Agricultural Engineering, Athens , Georgia.
Presented at the Annual Meeting of the American Society of Civil Engineers, Paper
No. 76-2039, June 27-30, 1976, Lincoln, Nebraska. 12 p, 2 fig, 3 tab, 10 ref,
Descriptors: Peaches, *Sprinkler irrigation, *Evaporation, *Model studies. Or-
chards, Irrigation systems, Irrigation effects, Irrigation practices, Forecasting.
The Utah Pheno-Climatography Model was used to predict rest completion and bloom
dates for Loring Peach Trees, Individual tree sprinklers with an application
rate of -086 per hour (.218 cm/hr) were utilized over a 13^day period to achieve
a 14-day bloom delay-
77:03F-087
THE DEVELOPMENT OF A FURROW-MULCH RIDGER,
Richey, C.B., and Griffith, D.R.
Purdue University, Department of Agricultural Engineering, Lafayette, Indiana.
Presented at the 1976 Winter Meeting of the American Society of Agricultural
Engineers, December 14-17, 1976, Chicago, Illinois. 18 p, 7 fig, 3 tab, 16 ref.
Descriptors: *Furrow irrigation, *Mulching, Cultivation, Surface irrigation.
Erosion, Erosion control. Furrows, Flow resistance, Soybeans, Weed control, Plant
growth.
A tillage tool to form ridges for row crops but leave residue on the surface in
the furrows has been developed. It gives promise of combing early plant^growth
and weed control approaching plowing with moisture conservation and erosion con-
trol approaching the no-till system.
149
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77;03F-088
OPTIMAL ON-FARM ALLOCATION OF IRRIGATION WATER,
Trava, J., Heermann, D.F., and Labadie, J.W.
Escuela Nacional de Agricultura, Colegio de Postgraduados, Chapingo (Mexico).
Presented at the Annual Meeting of the American Society of Agricultural
Engineers, Paper No 76-2040, June 27-30, 1976, Lincoln, Nebraska. 14 p, 4 tab,
23 ref.
Descriptors: * Irrigation water, Optimization, *Water allocation, Model studies,
Simulation analysis, Crop production, Systems analysis, Water delivery.
The USDA-ARS Scheduling Program is a powerful tool to assist management in the
efficient use of irrigation water on the farm. The Water Management Program
incorporating an optimization technique provides a tool for scheduling irriga-^
tion within constraints of water and labor. The application of systems analysis
in making operational real-time management decisions has far-reaching possibilities
for further development. More complex objective functions and additional con-
straints will provide even more assistance to management. The application of
the Dantzig-Wolfe decomposition principle to large-scale water management problems
demonstrates a feasible way of using systems analysis for operational problems.
77:03F-089
HOW ACCURATE ARE SHOP-MADE ORIFICE PLATES,
Ree, W.O.
Agricultural Research Service, Water Conservation Structures Laboratory, Stillwater,
Oklahoma.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 2,
p 298-300, March-April, 1977. 3 fig, 2 tab.
Descriptors: Irrigation, *Flow measurement, *0rifice flow. Orifices, Measure-
ment, On-site data collections, Equipment, Gages, Flow, Irrigation ditches,
Irrigation engineering, Water delivery, Irrigation efficiency.
Efficient use of irrigation water may require field measurement of furrow flows,
A plate with a circular orifice, together with a simple hook gage (both readily
made in any sheet metal shop), can be used to measure the flows. However, the
orifice may not be perfect, and its accuracy is doubtful. Tests of a sample
lot of orifice plates showed that errors in flow measurement could be as large
as 15% for a 2.54-cm diameter orifice. For a 8.89-cm diameter orifice, the maxi-
mum error would probably be about 2%. The errors are tolerable for rough flow
measurements but not for a more accurate measurement. The head measuring tech-
nique was checked and found to be satisfactory,
77:03F-090
IRRIGATION MANAGEMENT OF SHORT-SEASON, HIGH-DENSITY COTTON,
Mohammed, R.A., and Fangmeier, D.D.
Arizona University, Department of Soils, Water and Engineering, Tucson, Arizona,
Presented at the 1976 Winter Meeting of the American Soceity of Agricultural
Engineers, December 14-17, 1976, Chicago, Illinois, 9 p, 4 tab, 17 ref.
Descriptors: Irrigation systems, *Cotton, *Soil moisture, *Crop production,
Irrigation, Soil water, Crop response, Nutrients, Fertilization, Nitrogen, Water
management (applied).
An available soil moisture depletion of 50 to 55% at irrigation will give the
highest yields for short-season, high-density cotton. This is compared to about
65% for conventional cotton. Changing the scheduling criteria during the season
tended to reduce yields. Application of 100 pounds of N per acre appears ade-
quate for the soils studied. This provided adequate nitrogen for plant growth
but did not result in high petiole nitrate values late in the season. For high-
est yields irrigation termination should be based on observations of boll load
and maturity. Later irrigations tend to delay boll opening while terminating
too early reduces yields and fiber quality. Careful monitoring of soil mois-
ture and plant condition is both necessary and satisfactory for irrigation
scheduling. With experience, feel and appearance of soil moisture condition
were adequate for irrigation scheduling. Other methods were more expensive and
time consuming but were no better than field observations. Yields were comparable
ISO
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to those obtained with conventional cotton;. Water requirements were similar to
those for conventional cotton. Early termination reduced the number of irrigations
by one and in 1974 reduced the yield by 17%,
77:03F-091
ROW CROP "DRIP" IN FLORIDA: WATER AND FERTILIZER SAVINGS SPEED ACCEPTANCE,
Irrigation Journal, Vol. 27, No. 3, p 48-49, May-June, 1977, 7 fig,
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Fertilization,
Crop production, Florida, Water conservation.
Several years of commercial use of drip irrigation in San Diego County, California
to grow tomatoes, cucumbers, squash, strawberries and peppers has demonstrated
anywhere from 25 to 50 percent water savings, to say nothing of the improved
crop production and quality- Commerical vegetable crop acreage under drip or
trickle irrigation has soared from 1,500 to 4,500 acres between 1975 and 1976.
77:03F-092
DRIP IRRIGATION MANAGEMENT,
Davis, S.
United States Department of Agriculture, Agricultural Research Service, Riverside,
California.
Water and Irrigation, p 14-15, 29-30, November 1977. 2 fig.
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Irrigation
efficiency.
Management is unquestionably the most important factor in the use of drip ir-
rigation. To be successful and to accomplish its purpose, drip irrigation re-
quires sound decisions on the part of designers, installers and operators. If
the proper equipment is not selected for the soil and water conditions and the
equipment installed and operated as designed, then drip irrigation will not ful-
fil its full capacity to most efficiently utilize energy and water,
77:03F-093
WATERA CRISIS MORE SERIOUS THAN ENERGY,
Jauregui, L.U.
United Nations Center for Economic and Social Information, OPI/CESI NOTE WATER/14.
Magazine of the International Water Resources Association, Vol, 2, No. 1, p 25-26,
March 1977.
Descriptors: Water, Water conservation, Water supply, Water resources, Water
supply development.
The demand on the world's finite water supply is growing daily, because of the
increased population, the concentration of people in certain areas and the in-
dustrialization process. At the same time, the quality of water has deteriorated
because of these factors. We must take care of our water supply, And to do that,
we have to change our attitude towards it.
77:03F-094
DRIP/TRICKLE IRRIGATION SCHEDULING,
Rodriguez, R.
Superior Farming Company, Department of Irrigation Engineering, Bakersfield,
California.
Water and Irrigation, p 21-26, November 1977, 1 tab.
Descriptors: Irrigation, Irrigation practices, Irrigation efficiency, Irrigation
methods. Soil moisture, Evapotranspiration.
The preliminary results obtained so far have been plotted. The applied water,
crop ET and the soil moisture content are plotted against time, Applied water
and ET are plotted in inches per week, every week. The moisture content (as
measured with the neutron probe) is shown in inches of water per foot of soil.
151
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77-.03F-095
SEEPAGE CONTROL BY PARTICLE SIZE SELECTION,
Hauser, V.L.
United States Department of Agriculture, Agricultural Research Service, Grassland-
Forage Research Center, Temple, Texas 76501.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State Univer-
sity, p 1-10. 5 fig, 1 tab, 12 ref.
Descriptors: Seepage, Canal seepage, Hydraulic conductivity, Soil particles,
Clays.
The hydraulic conductivity of soils can be substantially reduced by the addition
of gravel or aggregates which are at least 15 times larger than the particle
size of the soil. The amount of clay required to control seepage can be reduced
by half by the addition of aggregates at least 15 times larger than the particle
size of the base soil,
77:03F-096
SIMULATING THE RESPONSE OF CORN TO IRRIGATION IN HUMID AREAS,
Barfield, B.J., Duncan, W.G., and Haan, C.T.
Kentucky University, Department of Agricultural Engineering, Lexington, Kentucky
40506.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-23. 5 fig, 1 tab, 21 ref, 1 append.
Descriptors: Simulation analysis, Model studies, Corn, Irrigation, Irrigation
effects.
A description is given of the Duncan Model for simulating the growth and yield
of corn. The accuracy of the model for predicting yields of irrigated and non-
irrigated corn is evaluated using 12 plot years of data,
77:03F-097
CENTER PIVOT WITH DROP OUTLETS DIRECTS WATER TO ROOT ZONE,
Rodgers, N.
Littlefield, Texas.
Irrigation Age, Vol. 11, No. 5, p 36-37, 39, February 1977. 2 fig.
Descriptors: Irrigation efficiency, Water conservation, Irrigation methods,
Irrigation practices, Surface irrigation, Evaporation.
The use of a pivot sprinkler now on loan to the Texas Agricultural Experiment
Station (TAES) could revolutionize sprinkler systems where evaporation losses
are high due to wind velocity. The newest idea in center pivot irrigation and
an old idea called furrow diking to hold rainfall have been combined at the
TAES in Lubbock. The melding of the latest ideas in irrigation and the hold-
over damming practice from the dust bowl days is a totally new way to get
maximum returns out of a limited amount of water,
77:03F-098
STRAIGHT SHOT HERBIGATION,
Welsh, G.
NEBCO Corporation, Holyoke, Colorado,
Irrigation Age, Vol. 11, No. 5, p 46, February 1977, 2 fig.
Descriptors: Herbicides, Sprinkler irrigation, Colorado, Irrigation practices.
Crop production, Corn.
Direct injection of a herbicide through sprinklers has not been attempted on a
large scale in Colorado. At least not until last year when Gene Welsh, Manager
of NEBCO Corporation in Holyoke, applied straight Sutan+ with atrazine through
center pivots on several circles of corn. Most growers who herbigate corn dilute
the chemical in a holding tank before injecting it into the sprinkler. Because
herbicides require small amounts of chemical per acre, many farmers claim it is
152
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too difficult to accurately inject the proper rates in this manner, so they blend
it with large batches of water before injection. This popular method has proved
to be effective but according to Welsh, who has used both methods, "It's definitely
easier to inject the straight herbicide. It's a trouble-free process and calibra-
tion is much simpler."
77:03F-099
SOIL PROPERTIES AND IRRIGATION,
Grimes, D.W.
California University, Department of Land, Air and Water Resources, Water Science
and Engineering Section, Davis, California.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 40-44, February 13-15, 1977. 2 fig, 3 tab, 8 ref.
Descriptors: Soils, Soil properties, Irrigation, Irrigation effects. Root develop-
ment, Soil moisture, Soil water. Soil investigations, Soil environment, Soil
physical properties.
Consideration of all soil properties important to water management decisions is
beyond the scope of this report. Emphasis is placed on some techniques for
using water related properties of soils in management decisions and impedance
characteristics that reduce effective plant root extension.
77:03F-100
TAILORING YOUR SOIL FOR DRAINAGE AND IRRIGATION,
Daniel, W.H.
Purdue University, Department of Agronomy, Lafayette, Indiana,
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 54-58, February 13-15, 1977.
Descriptors.: Irrigation, Drainage, Irrigation effects, Drainage effects. Soils,
Soil properties, Turf, Turf grasses, Irrigation design, Irrigation efficiency.
In much of the world, one of the most evident limitations of climate is the lack
of available water. The fantastic advancement of the irrigation industry has
been matched by the creative ideas of current installations. In the management
of fine turf areas, the reduction of the limitations has been the target for
many turf managers. Irrigation improvements have given most turf managers
excellent tools for the day-by-day application of water at preferred quantities,
at preferred times and under uniform application conditions. A study of several
18-hole golf course irrigation designs reveals that the number of heads being
used vary from 800 to 1200. These, when combined with satellites and controllers
for individual operations of the valves and heads, become effective systems.
Many, in fact, most turf areas are developed on existing natural soil. Obviously,
this includes a wide variety of soil types, each having varying infiltration
and drainage potentials. For intensely used turf areas, extensive soil modifi-
cations have evolved as systems of construction. Four of theses-vertical trenching,
sand bedding, Purr-wick and PAT systems should be of interest.
77:03F-101
DRIP AS SUPPLEMENTAL IRRIGATION,
Nye, J.R.
Trickl-Eez Company, Saint Joseph, Michigan,
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 73-76, February 13-15, 1977.
Descriptors: Supplemental irrigation, Irrigation systems, Irrigation practices,
Water conservation. Irrigation efficiency.
The use of drip or trickle irrigation as a supplement to natural rainfall is
finding increased usage throughout the Midwest, Eastern and Southern states. By
using technology developed mainly in California and the other western states,
where drip irrigation has found widespread use as an efficient labor saving method
of irrigation, growers who have never irrigated before are adapting it to orchards,
vineyards, vegetable croplands, and it may even find usage in field crops.
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77:03F-102
FERTILIZATION WITH DRIP IRRIGATION: CONCEPTS, PRACTICES AND PROBLEMS,
Francis, L.
Agrispect, Incorporated, Riverside, California.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 80-83, February 13-15, 1977. 2 fig.
Descriptors: Irrigation, Irrigation effects, Irrigation practices, Fertilization,
Fertilizers, Nutrients,
Fertilizer needs of our crops can be largely applied by means of injection through
the drip irrigation system, so long as the proper equipment is used and the
chemicals used are thoroughly understood,
77:03F-103
PECULIARITIES OF DRIP IRRIGATION SYSTEM DESIGN,
Olson, B.R., Jr.
Olson Engineering Systems, Indio, California.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 84-87, February 13-15, 1977.
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Soils, Soil
properties, Water conservation, Irrigation design, Sprinkler irrigation.
Drip irrigation is generally considered as a point source application of water
at a rate that does not exceed the basic intake rate of the soil. There are
certain criteria or "peculiarities" concerning drip irrigation system design as
compared to sprinkler or surface irrigation systems. The design engineer is
responsible for critically analyzing these criteria,
77:03F-104
BUYING AUTOMATIC IRRIGATION,
Kennedy, S.
Weeds, Trees, and Turf, Vol. 16, No, 1, p 15, 18, January 1977, 1 fig,
Descriptors: Irrigation, Irrigation practices. Irrigation systems, Irrigation
efficiency, Automation, Automatic control, Turf,
After 44 years with the same irrigation system, the Columbus Country Club decided
to replace it. Here, Superintendent Steven Kennedy tells how he went about doing
so and offers some advice to superintendents who plan to replace their systems.
77:03F-105
A LOOK AT THE DRIP/TRICKLE INDUSTRY,
Fraser, G.O., Jr.
Water and Irrigation Magazine.
Water and Irrigation, p 5-11, 27-28, November 1977. 5 fig, 2 tab.
Descriptors: Irrigation, Irrigation efficiency, Irrigation practices, Water
conservation.
Leaders of the drip/trickle irrigation industry present their ideas regarding
the state-of-the-art of this type of irrigation.
77:03F-106
CAN SUNSHINE POWER THE IRRIGATION PUMP?
Abernathy, G.H., and Mancini, T.R,
New Mexico State University, Department of Agricultural Engineering, Las Cruces,,
New Mexico 88003.
Agricultural Engineering, Vol. 58, No. 10, p 39-40, October 1977, 1 fig.
Descriptors: Irrigation, Irrigation practices, Pumps, Pumping, Plants, Solar
radiation, New Mexico, Electrical equipment, Electricity, Electrical power
production, Electric power.
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The Torrance County Land and Livestock Company in New Mexico's Estancia Valley
is the site of the new experimental solar-powered pumping plant funded by the
State of New Mexico and ERDA. Sandia Laboratories engineered the pumping system.
New Mexico State University will conduct the agricultural experiments. Three
crops will be grown yearly.
77:03F-107
SOLAR ENERGY TO POWER IRRIGATION PUMPS,
Agricultural Engineering, Vol. 58, No. 7, p 41-42, July 1977. 2 fig.
Descriptors: Irrigation, Irrigation practices, Pumps, Pumping plants, Pumping,
Solar radiation, New Mexico, Electrical equipment, Electricity, Electrical
power production, Electric power.
The sun powers the sump pump in the experimental irrigation system now operating
at Gila Bend, Arixona. The system, developed by Battelle Memorial Institute
with financial backing by Northwestern Mutual Life Insurance Company, delivers
10,000 gpm to 25,000 acres planted in cotton, wheat, barley, alfalfa and safflower.
77:03F-108
SHOULD YOU BE USING NITRAPYRIN?
Walsh, L.M.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Crops and Soils Magazine, Vol. 30, No. 1, p Sr-lO, October 1977. 1 fig, 2 tab.
Descriptors: Nitrogen, Fertilizers, Fertilization, Nutrients, Crop production.
A new product called N-Serve (nitrapyrin) has been getting a lot of attention
since its commerical introduction last fall. This product is designed to cut
losses of nitrogen fertilizer.
77:03F-109
ROUNDTABLE: IRRIGATION-FERTIGATION,
Caldwell, A.C., Murphy, L.S., Tucker, B.B., Wiese, R.A., and Zubriski, J.C,
Minnesota University, Department of Soil Science, Minneapolis, Minnesota 55455,
Crops and Soils Magazine, Vol. 29, No. 7, p 14-21, April-May, 1977, 5 fig.
Descriptors: Nitrogen, Nutrients, Fertilizers, Fertilization, Rainfall, Soil
water. Soil moisture, Economics.
Various experiments of irrigation-fertilization are presented by five authoritative
authors. The fertilization time frame and injection of fertilizers in irrigation
water and the economics of fertilization are considered,
77:03F-110
OUR NEWEST NATURAL RESOURCECOMPACTIONGOOD AND BAD EFFECTS ON ENERGY NEEDS,
Voorhees, W.B., and Hendrick, J.G.
United States Department of Agriculture, Agricultural Research Service, Morris,
Minnesota.
Crops and Soils Magazine, Vol. 29, No. 7, p 11-13, April-May, 1977, 1 fig.
Descriptors: Soil properties. Soil compaction, Soil density, Soil erosion,
Runoff, Soil management, Soil structure, Soil physical properties, Bulk density,
Crop production.
Soil compaction caused by wheel traffic during normal farming operations can
create serious soil erosion and water runoff problems, and can drastically
restrict root growth and reduce crop yields.
77:03F-111
DEEP PLOWING, CURE FOR SOD1C CLAYPAN,
Sandoval, P.M., and Jacober, F.C,
United States Department of Agriculture, Agricultural Research Service, Mandan,
North Dakota.
Crops and Soils Magazine, Vol. 29, No. 7, p 9-10, April-May, 1977, 1 fig.
-------
Descriptors: Soil investigations, Soil tests, Soil types,
structure, Soil profiles.
Soil treatment, Soil
Sodic claypan soils are not desirable. More common names for this type of soil
are scabland, scabspot land, or panspot land. How common are these soils? We
have about 17 million acres in the Northern Great Plains. There are another
12 million acres to the north in the Canadian prairie provinces.
77:03F-112
SUGAR BEET RESPONSE TO WATER STRESS IN SANDY SOILS,
Stegman, B.C., and Bauer, A.
North Dakota State University, Department of Agricultural Engineering, Fargo,
North Dakota.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 469-473, 477, June 20, 1977. 12 fig, 1 tab, 13 ref, 1 equ.
Descriptors: Sugar beets, Plant growth, Crop response. Crop production, Soil
water, Irrigation effects, Soil moisture, Leaves.
Leaf xylem pressure data suggest brief reductions to about -14 to -15 bars may
be tolerable provided average pressure over 10-20 day intervals is above <-i2
bars. Seasonal average pressures of -15 and -21 bars were found to reduce
yields to 0.6 and 0.1 that of a nonstress treatment, respectively. Water manage-
ment criteria based upon allowable levels of leaf xylem pressure are suggested.
77:03F-113
CALCULATING THE COST OF EACH IRRIGATION,
New, L.
Texas A and M University, Texas A and M Research Center, Lubbock, Texas.
Irrigation Age, Vol. 11, No. 9, p 56-57, July-August, 1977.' 2 tab.
Descriptors: Irrigation, Irrigation practices, Irrigation efficiency, Pumping,
Economics.
In view of today's energy costs, excessive irrigation amounts and poor field
distribution patterns can seriously damage the profitability of a farming
enterprise. You may have a good idea of your total pumping time, and your
annual fuel costs per acre of land. But the best lead to your irrigation ef-
ficiency is to know how much water is pumped, and where it's going. You can
obtain those figures by knowing your irrigation well capacity and the number
of hours that a well or group of wells are pumped to irrigate a specific
acreage. The specific acreage can be an irrigation set, a section of land,
a field of corn, or even the actual acreage irrigated by a center pivot sprinkler.
77:03F-114
DRIP IRRIGATION STRIKES BACK AT WATER SHORTAGES,
Davis, S.
California University, Department of Agricultural Engineering, Riverside,
California.
Irrigation Age, Vol. 11, No. 9, p 31, 35, July-August, 1977,
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Water
conservation.
To solve the drought problem facing us in 1977, or during any dry year, we must
learn to store more water and make more use of our available water. One ef-
ficient way to accomplish the latter is with drip irrigation,
77:03F-115
SUGAR BEETS TOLERATE MORE LIMITED IRRIGATION,
New, L.
Texas A and M University, Texas A and M Research Center, Lubbock, Texas.
Irrigation Age, Vol. 12, No. 1, p 51-52, September 1977. 2 fig, 1 tab.
Descriptors: Sugar beets, Irrigation, Irrigation effects, Irrigation practices,
Water conservation, Evapotranspiration.
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Sugar beets, once considered to have high and critical demands for water, have
yielded well under more limiting irrigation in field tests near Hereford, Texas.
In 5-year irrigation demonstrations, sugar beets that were irrigated on 3-week
intervals averaged 27.3 tons per acre, while beets that were irrigated on 2-week
intervals averaged 26.7 tons. Irrigation applications averaged about 8 inches
less when irrigating on the 3-week frequency. In a third comparison, sugar beets
irrigated on 4-week intervals averaged 24,3 tons per acre.
77:03F-116
CONTROLLING SEDIMENT IN SURFACE RUNOFF,
Huropherys, A.
Snake River Conservation Research Center, Agricultural Engineering Division,
Kimberly, Idaho.
Irrigation Age, Vol. 12, No. 1, p 22, 24, September 1977, 1 fig.
Descriptors: Sediments, Nutrients, Runoff, Irrigation, Irrigation effects,
Pesticides, Fertilizers, Salts,
Irrigators are sometimes criticized for contaminating downstream waters with
sediment, nutrients and pesticides contained in surface runoff from irrigation.
Research studies have shown that the concentrations of dissolved fertilizer
nutrients, pesticides and salts in surface runoff are essentially the same as
those in the applied irrigation water. Thus, water passing over the soil sur-
face does not usually pick up additional amounts of these materials. Signifi-
cant increases in nutrient or pesticide concentration do occur when these materials
are applied by adding them to the irrigation water or when the material falls into
the water from spray applications or washed from the plants by rain. When ferti-
gation and herbigation are practiced, runoff water should be retained in a reuse
pond and not allowed to leave the farm or flow into natural streams.
77:03F-117
MONITORING SAVES MONEY AND WATER,
Ruen, J.
Irrigation Age, Vol. 12, No, 1, p 16, 19, September 1977. 2 fig.
Descriptors: Irrigation efficiency, Crop production, Nebraska, Scheduling, Water
conservation.
Cut energy costs, increase water efficiency, boost yields. And, save money and
water at the same time. Sound impossible? Nebraska farmers are doing it with
irrigation scheduling and a little help from their friends,
77:03F-118
HOW THEY'RE HARNESSING THE SUN TO PUMP WATER,
Larsen, R.
Irrigation Age Magazine.
Irrigation Age, Vol. 12, No. 2, p 6-8, October 1977. 4 fig.
Descriptors: Irrigation, Irrigation practices, Irrigation systems, Solar radiation.
Natives worshipped it; sunbathers sought it, and farmers welcomed it. Despite all
this attention given to the sun, serious efforts to harness the sun's rays for
energy have been few. Now there is a major attempt by private firms and govern-
ment agencies to find a way of using sunlight to power the nation's irrigational
systems.
77:03F-119
IRRIGATION AND WILDLIFE: CAN THEY BE COMPATIBLE?
Nelson, M.J.
Irrigation Age, Vol. 12, No. 3, p 8-9, 16, Novembers-December, 1977. 5 fig.
Descriptors: Wildlife, Wildlife habitats, Irrigation, Irrigation effects,
Wildlife management.
157
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Irrigation and wildlife would seem to be mutually exclusive. Bulldozing trees
to accomodate center pivot systems, the tendency toward monoculture encouraged
by the big systems, and the elimination of fencerows and traditional field edges
are an anathema to wildlife. To listen to the voices of gloom and doom com-
plaining about the loss of habitat in the country, it would seem that irrigation
is in large part responsible for the decline of the pheasant, the quail, the
deer, and the whooping cranes. They would have you believe that it is possible
to have irrigated crops in an area, or produce wildlife, but not both. However,
the picture is not that bleak, not at all, in fact. With small, seemingly
insignificant changes in farming practices, irrigation can be greatly beneficial
to wildlife, even in areas where it is heavily developed.
77:03F-120
MAKING THE DESERT FLOWER: IRRIGATING CALIFORNIA'S IMPERIAL VALLEY,
Mallory, R.
Irrigation Journal, Vol. 27, No. 5, p 19-20, 27, September-October, 1977. 2 fig.
Descriptors: California, Water conservation, Water quality, Crop production,
Salinity, Saline soils, Furrow irrigation.
"Making the desert flower" is a description heard many times in the irrigated
farmlands of the West. But perhaps nowhere is the description more appropriate
than in California's Imperial Valley- With less than three inches of rain per
year in this southern-most California valley, the land could not even be initiated
into dryland wheat production as was much of the rest of the state,
77:03F-121
DRIP STUDY SHOWS UP TO 30% WATER SAVINGS,
Schleicher, J.
Irrigation Age, Vol. 11, No. 4, p 37, 69, January 1977.
1 fig,
Descriptors: Irrigation, Irrigation practices, Irrigation systems, Irrigation
efficiency, Orchards, Crop production, Water conservation.
Tree crop farmers repeatedly hear how efficient drip irrigation is in relation
to either sprinkler or furrow water application methods. But just how does
"drip efficiency" stack up in terms of comparative water savings with sprinkler
and furrow techniques? That question is the subject of a joint research project
currently being sponsored by the University of California and the California
Department of Water Resources on a citrus farm near Parlier, California. The
study centers around a 40-acre block of 8-year-old Navel oranges, chosen for the
uniformity of soil, water and tree conditions. The acreage is divided into 12
five-row blocks, permitting the researchers to create four replications each of
the three irrigation methods ,
77:03F-122
DRIP IRRIGATION AT SUPERIOR FARMING! WATER USE CUT 30%, FERTILIZER 50% BY THIS
LARGE CORPORATE FARM,
Mallory, R.
Irrigation Journal.
Irrigation Journal, Vol. 27, No. 3, p 20-21, May-June, 1977, 5 fig.
Descriptors: Irrigation, Irrigation practices, Irrigation systems, Irrigation
efficiency, Water conservation,
Superior Farming Company, which first started its drip irrigation experiments in
1971, had its 8,000 acres of trees and vines under drip by 1975^ 20 percent of
the total drip irrigated acreage in California at the time,
77:03F-123
DEAD LEVEL FIELDS SIMPLIFY AUTOMATING IRRIGATION: ARS EXPERIMENTS IN ARIZONA,
Irrigation Journal, Vol. 27, No. 5, p 16, 25, September-October, 1977. 1 fig.
Descriptors: Irrigation, Irrigation efficiency, Crop production, Automation,
Flood irrigation, Furrow irrigation.
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Irrigators in the Southwest are increasingly taking part in a trend that promises
to improve irrigation efficiency, raise crop production, and simplify automating
water distribution systems. That trend is to level cropland to zero gradedead
level.
77-.03F-124
3-WHEELED "MOSQUITO" IRRIGATES FROM DITCH,
White, J.
Denver, Colorado.
Irrigation Age, Vol. 11, No. 7, p 80-81, 86, April 1977. 2 fig.
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Irrigation
efficiency.
A farmer has designed a self-propelled irrigation "tractor" that looks amazingly
similar to a mechanical mosquito. The "Mosquito" combines the advantages of
circular pivot irrigation systems with the low cost of gravity irrigation. This
new machine has helped increase yields on corn, wheat, barley and lettuce, the
primary crops in the San Luis Valley in Southern Colorado, because the "Mosquito"
provides more efficient use of water. The "Mosquito" also requires less super-
vision than some other irrigation systems, and produces higher yields and better
water efficiency.
77:03F-125
AUTOMATION ASSURES PRECISE DELIVERY, CUTS LABOR,
Irrigation Age, Vol. 11, No. 8, p 31-32, May-June, 1977.
1 fig,
Descriptors: Automation, Irrigation, Irrigation systems. Irrigation practices,
Irrigation efficiency, Arizona.
A study was undertaken in the Wellton-Mohawk Valley area to utilize automation
to two common methods of turning water into a fieldjack-gates and tile outlets.
Farmers who grow wheat, alfalfa or cotton in the Wellton-Mohawk Valley operate
on fairly tight soils, either clay loams or silty clay loams. Fields are generally
dead-leveled (level basins) and the types of outlets discussed, jack-gates and
tile outlets, were used. It was determined that both types of systems could be
successfully automated. However, thus far, jack-gates have proved more effective,
77:03F-126
CORN AND ALFALFA PRODUCTION AS INFLUENCED BY IRRIGATION AND SALINITY,
Hanks, R.J., Sullivan, T.E., and Hunsaker, V.E.
Utah State University, Logan, Utah,
Soil Science Society of America Journal, Vol. 41, No, 3, p 606-610, Mayr-June, 1977,
5 fig, 6 tab, 9 ref.
Descriptors: Corn, Alfalfa, Crop response, Salinity, Soil moisture, Irrigation
effects, Evapotranspiration, Crop production,
Yields of corn and alfalfa were determined where both salinity and water stress
were imposed. Yields of corn at Logan, Utah in 1975 were decreased by salinity
or water stress (caused by low irrigation levels) in direct relation to the
decrease in evapotranspiration. The decrease in evapotranspiration was caused
by a decrease in soil water depletion, indicating that salinity influenced soil
water availability- Corn yields at Vernal, Utah in 1974 were decreased by salinity,
but to a considerably lesser extent by low irrigation, probably because of water
flow upward into the root zone from a water table. Alfalfa yields at Vernal in
1974 were not decreased by salinity or by low irrigation rates, because of water
supplied by a water table and used by roots below the zone of salinity,
77:03F-127
SOURCES, RATES, AND FREQUENCIES OF N APPLICATION IN SUBIRRIGATED HAY MEADOWS,
Daigger, L.A., and Moline, W.J.
Nebraska University, Department of Agronomy, Lincoln, Nebraska,
Agronomy Journal, Vol. 69, No. 4, p 644-647, July-August, 1977, 4 fig, 2 tab,
10 ref.
159
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Descriptors: Subsurface irrigation, Irrigation systems, Nitrogen, Fertilizers,
Fertilization, Nutrients, Soil investigations, Urea.
Inadequate supplies of soil nutrients often limits hay production of western
United States subirrigated meadows. Our purpose was to evaluate the effective-
ness of three N-sources at various rates in alternating sequences of N-applied
annually, biennially, and triennially for meadow hay production.
77:03F-128
MEASURING THE AMOUNTS OF CROP RESIDUE REMAINING AFTER TILLAGE,
Sloneker, L.L., and Moldenhauer, W.C.
United States Department of Agriculture, Agricultural Research Service, Morris,
Minnesota 56261.
Journal of Soil and Water Conservation, Vol. 32, No, 5, p 231-236, September-
October, 1977. 6 fig, 5 tab, 10 ref.
Descriptors: Mulching, Crop production, Organic matter, Soils, Soil investiga-
tions, Tillage.
A simple method of estimating percent residue cover, and how to convert percent
residue cover to tons per acre was devised. Under certain conditions, more
than one fall mulch tillage operation can be performed without losing a large
percentage of residue cover. We also determined the percentage of cover re-
maining after row-crop planting using various tillage methods on different soils
at three locations.
77:03F-129
CHARACTERIZATION OF YIELD AND ECONOMIC LOSS FROM NONUNIFORM FERTILIZER DISTRIBUTION
USING COMPUTER SIMULATION,
Sorenson, R.C., and Wiese, R.A,
Nebraska Agricultural Experiment Station, Lincoln, Nebraska 68583.
Soil Science Society of America Journal, Vol. 41, No, 2, p 382-385, March-April,
1977. 4 fig, 2 tab, 10 ref.
Descriptors: Model studies, Simulation analysis, Computer programs, Fertilizers,
Fertilization, Nutrients, Crop production.
A simpler computer program has been developed to predict yield losses from uneven
broadcast fertilizer distribution on the basis of distribution pattern, yield
response curve, fertilizer rate, soil test rating and amount of fertilizer swath
overlap. Losses were serious only on soils classed "very low" in nutrient supply.
Losses for a highly responsive crop are less than for a less responsive crop.
Overlapping succeeding swaths may improve the appearance of a field, but has a
small effect on yield loss unless the amount of overlap is <50%. Visually evi-
dent streaks in plant growth patterns may not necessarily indicate high yield loss,
77:03F-130
THE FINE ART OF USING ENOUGH, BUT NOT TOO MUCH BORON,
Bowen, J.E.
Hawaii University, Department of Plant Physiology, Honolulu, Hawaii,
Crops and Soils Magazine, Vol. 29, No. 9, p 12-14, August-September, 1977. 2 fig,
1 tab.
Descriptors: Boron, Nutrients, Fertilizers, Fertilization, Crop production,.
Crop response.
During the past 50 years several seemingly different diseases have appeared in
different crops. These diseases were puzzlers to both farmers and agricultural
researchers. It has now been determined that all of these diseases are actually
caused by the same problem; a lack of boron,
77:03F-131
LONG-TERM STRATEGIES FOR SUPPLYING NITROGEN TO CROPS,
Gutschick, V.P.
California University, Los Alamos Scientific Laboratory, Los Alamos, New Mexico
87545.
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United States Energy Research and Development Administration, Publication No
LA-6700-MS, May 1977. 73 p, 136 ref, 3 append.
Descriptors: Nitrogen, Fertilizers, Fertilization, Crop production.
Raising food for present population requires nitrogenous fertilizers in addition
to indirect management of the biosphere's nitrogen cycle. The Haber process
for making the ammonia base of fertilizers is increasingly pressed by shortages
of energy, while only minor improvements are still possible. The Haber process
and 15 alternatives for increasing the nitrogen available to crops using less
fossil energy is discussed. These alternatives span technology of fertilizer
synthesis, farm management and technology, crop genetics, and market management,
77:03F-132
AGRONOMY ABSTRACTS, 1977 ANNUAL MEETINGS,
American Society of Agronomy
American Society of Agronomy, 677 South Segoe Road, Madison, Wisconsin 53711.
Agronomy Abstracts, Los Angeles, California, November 13-18, 1977. 198 p.
Descriptors: Model studies, Fertilization, Land use, Climatology, Environmental
quality, Crop production. Soil chemistry, Nutrients, Soil, Soil water, Fertilizers,
Soil physics.
This booklet contains the abstracts of each paper that was presented at the 1977
Annual Meetings of American Society of Agronomy, Crop Science Society of America,
and Soil Science Society of America.
77:03F-133
MORE GROWERS TURN TO HERBIGATION FOR WEED CONTROL,
Irrigation Age, Vol. 11, No, 4, p 47-48, January 1977, 2 fig, 1 tab.
Descriptors: Herbigation, Weed control, Herbicides, Irrigation, Irrigation
practices, Chemicals.
The beneficial effects of herbigation are described and equipment to accomplish
herbigation.
77:03F-134
THE BRIGHT SIDE OF LOW PRESSURE,
Irrigation Age, Vol, 11, No, 4, p 52, January 1977, 1 fig.
Descriptors: Sprinkler irrigation, Irrigation, Energy, Economics, Sprinklers,
The benefits of low pressure nozzles for sprinkler irrigation are described.
77:03F-135
POLICY OF PRICING IRRIGATION WATER,
Jain, J.K.
Ministry of Agriculture and Irrigation, New Delhi (India),
ICID Bulletin, Vol. 26, No. 1, p 41-49, January 1977, 2 tab, 14 ref.
Descriptors: *Pricing, *Water policy, *Irrigation, *Water rates, Economics,
Governments, Cost-benefit analysis, Economic developments, Economic impact,
Political constraints, Subsidization, Crop production, Agriculture, Water
management (applied), Cost repayment,
Based on analysis of irrigation water pricing issues and theory, a^guideline is
suggested for formulating governmental pricing policy and its application is
described for India. Major aspects are: (1) Subsidies up to 50% may encourage
irrigation use and minimize inflation in the initial stages of irrigation develop-
ment. (2) Assessment may be based on crop area in the interests of practicality
and convenience but volumetric pricing should be promoted wherever possible,
especially on tube wells. (3) In areas where farmers are not yet accustomed to
irrigation, a two-part tariff may be introduced in place of the simpler single
charge based on crop area. (4) Irrigation rates should be uniform unless there
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are strong reasons to introduce variable rates, such as variations in climate,
soil, irrigation systems, crop irrigation requirements, or utilization of
irrigation potential. Preindependence Indian pricing policy was based on strict
adherence to financial return, but since 1947 this criterion was initially re-
laxed and subsequently replaced by a cost-benefit standard in order to achieve
rapid development of irrigation. The result was very low water rates, heavy
government subsidization, and considerable diversity in the fixing of rates.
Recent trends on pricing are reviewed, with attention to quantum of water rates,
mode of assessment, water rate structure, and water rate uniformity/diversity.
77:03F-136
COMPUTER MODELING TO MAXIMIZE WATER USE EFFICIENCY AND REDUCE ENERGY IN IRRIGATION,
Gilley, J.R.
Nebraska University, Water Resources Center, 310 Agricultural Hall, Lincoln,
Nebraska 68583.
Project Completion Report A-038-NEB, 30 p, 10 fig, 9 ref.
Descriptors: Irrigation systems, Energy, Soil-water-plant relationships, Soil
moisture, Water conservation, Model studies, Mathematical models, Crop production,
Computer models.
A simplified irrigation scheduling model, IRRIGATE, has been developed as an
educational tool for use by University personnel and in extension programs, Ir-
rigations are scheduled using the basic premise of maximizing yields with a
minimum of applied irrigation water. Use of IRRIGATE has grown rapidly in Nebraska
and in addition to being used as an educational tool it was also used by private
individuals, private irrigation scheduling companies, irrigation districts and
others to schedule irrigations for approximately 25,000 acres during the 1977 sea-
son. A mathematical model, CORNGRO, has been developed to predict daily crop water
use, plant growth, and crop yield for corn, CORNGRO has the capability of pre-
dicting corn yield as a result of different irrigation timing and amounts. The
model can be useful in evaluating irrigation scheduling procedures in terms of
yield, water conservation, energy conservation, production costs, and analyzing
alternate levels of water applied, Tests of the model using data available from
Mead, Nebraska indicate the model has considerable predictive power, although not
all of the dynamics of crop growth are modeled in precise detail.
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SECTION XV
WATER QUANTITY MANAGEMENT AND CONTROL
CONTROL OF WATER ON THE SURFACE (GROUP 04A)
77:04A-001
LINKED MODELS FOR MANAGING RIVER BASIN SALT BALANCE,
Helweg, O.J., and Labadie, J.W.
California University, Department of Civil Engineering, Davis, California,
Water Resources Research, Vol. 13, No. 2, p 329r-336, April 1977. 6 fig, 8 ref.
Descriptors: *River basins, *Salt balance, *0ptimization, *Simulation analysis,
*Economic efficiency, *Water quality control, Management, Ground-water, Surface
waters, Streams, Aquifers, Downstream, Wells, Pumping, Irrigation, Demand,
Algorithms, Conjunctive use, Decision making, Equations.
A pressing problem facing the irrigation intensive areas of the world is the
increasing salinity of groundwater. A cost-effective salinity management tech-
nique, called the accelerated salt transport (Astran) method, has been developed
which may be feasible for many stream aquifer systems. The basic idea is to
encourage application of pumped water downstream of the well from which it is
pumped rather than within rts vicinity. In this way a mechanism is established
for accelerating the downstream transport of salts in the groundwater at a more
rapid rate than would occur naturally through convection and dispersion while
still satisfying irrigation demands. A management algorithm is developed for
implementing the Astran method which combines an optimizing model with a detailed
quantity-quality simulation model. The optimizing model generates least-cost
alternatives for distributing water over the basin. These alternatives are
subsequently examined by the simulation model as to their effectiveness in con-
trolling the salt balance. A parameter in the optimizing model can be adjusted
so as to produce a desired degree of salinity control. The management algorithm
has been applied to the Bonsall Subbasin in the San Luis Rey River Basin in
order to test its effectiveness. Results of the case study indicate that the
Astran method: (1) is cost-effective, requiring roughly 10% of the cost of
tiling for this area; (2) encourages balanced conjunctive use of surface water
and groundwater; and (3) is flexible enough to respond to future management
needs.
77:04A-002
FIELD EVALUATION OF SPRINKLER IRRIGATION FOR MANAGEMENT OF IRRIGATION RETURN FLOW,
Willardson, L.S., and Hanks, R.J.
Utah State University, Department of Agricultural and Irrigation Engineering,
Logan, Utah.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 109-114, May 16-19, 1977.
6 fig, 2 tab, 4 ref.
Descriptors: Salinity, Saline soils, Saline water. Irrigation, Utah, Leaching.
Sprinkler irrigation offers one alternative for control of irrigation water ap-
plication that influences quality of return flow, A two-year field scale study
of soil solution response to controlled water application using sprinklers was
conducted in the Ashley Valley near Vernal, Utah, The design level of water
control was attained with high coefficients of uniformity but the soil solution
did not respond as expected. The soil acted both as a source and a sink for
salt. Root zone salinity was only slightly affected by different leaching
fractions. Minimum average leaching fractions obtainable are influenced by
both the hydraulic design and operation of the system.
163
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77:04A-003
EFFECTS OF IRRIGATION MANAGEMENT ON SOIL SALINITY AND RETURN FLOW QUALITY,
Wierenga, P.J., and Sisson, J.B.
New Mexico State University, College of Agriculture and Home Economics,
Department of Agronomy, Las Cruces, New Mexico.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 115-121, May 16-19. 1977.
3 fig, 3 tab, 12 ref.
Descriptors: Saline soils, Irrigation systems, Surface irrigation, Water quality,
Groundwater, Irrigation efficiency, Soil water.
A field plot study was conducted to determine the effects of controlled surface
irrigation and trickle irrigation on soil salinity, and on the quality and quan-
tity of irrigation return flow. Changes in soil salinity were determined by
taking extensive soil samples at least once a year.. Return flow quality was
measured on soil solution removed through vacuum samplers in the subsoil of each
plot, and by analyzing the water quality at various levels below the groundwater
and in a nearby drain. The quantity of return flow was estimated from crop
growth and weather data, and amounts of water applied. This method was found
more reliable than several other methods used for determining percolation losses.
Results of the first three years of this ongoing study showed that a larger change
in soil salinity was produced by altering irrigation frequency than by changing
irrigation efficiency. Irrigating when 50 percent of the soil water had been
depleted was the irrigation frequency most conducive to salt retention in the
upper soil profile. However, different irrigation efficiencies and frequencies
had no significant effect on cotton yield due in part to the large spatial
variability of the physical properties of the soil at the site.
77:04A-004
EFFECT OF IRRIGATION SYSTEMS ON WATER USE EFFICIENCY AND SOIL WATER SOLUTE
CONCENTRATIONS,
Wendt, C.W., Onken, A.B., Wilke, O.C., Hargrove, R., and Bausch, W,
Texas Agricultural Experiment Station, Lubbock, Texas.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 123-131, May 16-19, 1977.
9 tab, 8 ref.
Descriptors: Subsurface irrigation, Irrigation efficiency, Sprinkler irrigation,
Furrow irrigation, Texas, Irrigation water, Return flow.
The effect of spinkler irrigation (Sp), furrow irrigation (.F), subirrigation (Su),
and automated subirrigation (ASu) systems on water use efficiency and soil water
solute concentration was evaluated at a field site in Knox County, Texas. Signifi-
cant differences existed in the irrigation water requirement of sweet corn irrigated
by the different systems (F > Sp approximately = Su > ASu). However, little
difference in total water requirement existed between systems -- the soil water
was utilized more efficiently (ASu > Su approximately = Sp > F), Automation of
irrigation systems offers the possibility of significantly enhancing irrigation
water use efficiency of supplemental irrigated areas, Soil water solute concen-
trations were too low to be of concern relative to degrading the quality of ir-
rigation return flow due to the dilution effect of rainfall. In most cases, at
depths below 3.0m, the concentrations of the above solutes in the soil were less
than those of the irrigation water. Although soil water solutes were not a pro-
blem in the irrigation return flows, the lower concentrations of the ASu and Su
systems indicate that they may be superior to F and Sp systems in maintaining
the quality of irrigation return flows where solutes are a problem.
77:04A-005
AN ECONOMIC ANALYSIS OF IRRIGATION RETURN FLOW RECYCLE SYSTEMS IN THE CENTRAL
VALLEY OF CALIFORNIA,
Kinney, W., Horner, G.L., and Tanji, K.K.
California University, Department of Agricultural Economics, Davis, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 175-182, May 16^19, 1977.
2 tab, 6 ref, 1 append.
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Descriptors: Recycling, Irrigation districts, Return flow.
Irrigation return flow recycle systems have been used in California for a number
of years under a variety of crop rotations, soil characteristics and qualities
of irrigation water. Recycle systems operating on the field, farm and district
level were compared on the basis of cost in two areas of the San Joaquin Valley.
The effects of three scales of recycle systems on the least-cost combination of
irrigation water delivery systems and water management techniques were evaluated.
77:04A-006
ON-PARM METHODS FOR CONTROLLING SEDIMENT AND NUTRIENT LOSSES,
Fitzsimmons, D.W., Brockway, C.E., Busch, J.R., Lewis, G.C,,'and McMaster, G.M.
Idaho University, Department of Agricultural Engineering, Moscow, Idaho.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 183-191, May 16-19, 1977.
2 fig, 12 tab, 6 ref.
Descriptors: Sediments, Nutrients, Idaho, Irrigation, Irrigation water, Runoff,
Return flow, Sediment yield, Beans, Phosphates, Irrigation practices.
Field experiments were conducted in the Boise and Magic Valley areas of southern
Idaho during the 1975 and 1976 irrigation seasons to evaluate on-farm methods
for controlling sediment and nutrient losses from irrigated fields. In one
experiment, four 1.7 ha plots of field corn were continuously monitored during
the two irrigation seasons. Varying furrow stream sizes and stream cutback methods
were used to apply the same total amounts of irrigation water to three of the plots,
No control measures were used on the fourth plot. Runoff from two of. the first
three plots were run through a vegetated buffer strip at the lower end of the
field and then a settling basin. Runoff from the other two plots were run through
a basin only. The effects of each treatment and control measure on the quality
and quantity of return flow from these plots are presented. The results of
sediment and nutrient yield determinations on several other field sites in the
two study areas are also presented. The effects of various combinations of soil
types, crops, irrigation practices and sediment retention devices on sediment
and nutrient losses from these sites were evaluated,
77:04A-007
WATER DISTRIBUTION PATTERNS FOR SPRINKLER AND SURFACE IRRIGATION SYSTEMS,
Karmeli, D.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 233-251, May 16-19, 1977,
11 fig, 4 tab, 19 ref, 26 equ.
Descriptors: Model studies, Simulation analysis, Sprinkler irrigation, Irrigation
efficiency.
A linear fit model for sprinkler and power curve fit model for surface irrigation
systems, are suggested to represent actual patterns of distributions in irrigated
fields. Both models allow for efficient calculation of surplus and deficient
volumes, as well as the various relevant efficiencies. Both environmental and
economical aspects require desired efficiency combinations to be followed,and this
may be done when the irrigation systems are represented by the suggested models.
Also, the various functions related to irrigation performance, may be integrated
to reach optimal results.
77:04A-008
APPLICATION OF MODERN IRRIGATION TECHNOLOGY IN THE MESILLA VALLEY, NEW MEXICO,
Sammis, T,W., and Hohn, C.M.
New Mexico State University, Department of Agricultural Engineering, Las Cruces,
New Mexico.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 269-276, May 16-19, 1977,
2 fig, 4 tab, 3 ref.
165
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Descriptors: Irrigation systems, Surface irrigation, Irrigation efficiency,
Saline soils, Rio Grande River, Return flow, Irrigation, Orchards, Alfalfa,
Root zone.
Current engineering technology is being applied to a Demonstration Farm in the
Mesilla Valley, New Mexico to demonstrate the feasibility of decreasing the
large amount of salt returned to the Rio Grande River System through return
flow drainage. The reduction in return flow is accomplished by irrigation
scheduling techniques and more efficient irrigation methods, such as drip ir-
rigation. A small pecan orchard has been converted from flood irrigation to
drip irrigation resulting in the water application reduction greater than 50
percent with a marked visible increase in growth rate over that of the previous
year. Irrigation scheduling increased the efficiency of irrigation timing on
the farm resulted in an improved soil condition, in some cases one less irriga-
tion. Monitoring of the applied water on the Demonstration Farm resulted in
estimates of irrigation efficiencies for the season ranging from 54 percent
for wheat to 97 percent for alfalfa. The high efficiency for alfalfa was
probably due to the high water table which contributed water to the crops in
addition to the applied water. Monitoring of the soil salinity is enabling
the investigators to follow the movement and buildup of salt below the root
zone with increased irrigation efficiencies. Information gained from the
Demonstration Farm is being used by the Cooperative Extension Service in an
educational program. The various methods used to make the public aware of
EPA's efforts on the Demonstration Farm include media releases, tour brochures,
and field days.
77:04A-009
ECONOMICS OF CONTROLLING IRRIGATION RETURN FLOW IN THE MESILLA VALLEY, NEW
MEXICO,
Lansford, R.R., Gelhar, L,W., and Creel, B,J.
New Mexico State University, Las Cruces, New Mexico.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins,. Colorado, p 277^282, May 16^-19, 1977.
4 fig, 1 tab, 6 ref.
Descriptors: Model studies, Water quality, Water management (Applied), Irri-
gation, Irrigation water. Return flow.
Preliminary budgeting indicates that net returns of water are reduced by incor-
poration of irrigation water management practices, but that irrigation water
requirements may be reduced. Thus, incorporation of these improved irrigation
water management practices may be feasible under restricted water availability
constraints. If irrigation water use can be reduced without affecting the local
agricultural economy by optimal crop selection incorporating the improved
practices, the quantity of irrigation return flows may be reduced and possibly
the quality may be improved. Further evaluation in the current and last year
of the three-year project will provide opportunities for refinements and sensiti-
vity evaluation in the linear programming model as well as more extensive itera-
tive analysis with the hydrological model,
77:04A-010
WELLTON-MOHAWK ON-FARM SYSTEMS IMPROVEMENT PROGRAM,
Swenson, R.S.
United States Department of Agriculture, Soil Conservation Service, Phoenix,
Arizona.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 349-351, May 16-19, 1977,
1 tab, 2 ref.
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Irrigation
efficiency, Return flow.
The objective of the SCS in the Wellton-Mohawk Irrigation Improvement Program is
to increase irrigation efficiency on farms in the district and thereby reduce
return flows from the district. To accomplish this, the SCS enters into contracts
with eligible landowners and operators to implement conservation practices that
will further the program goals. Cost sharing is provided on a 75% federal, 25%
cooperator basis.
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77:04A-011
THE USE OF LONG-THROATED FLUMES TO MEASURE PLOWS IN IRRIGATION AND DRAINACF
CANALS,
Bos, M.G.
International Institute for Land Reclamation and Improvement, Waqenengin, The
Netherlands.
Agricultural Water Management, Vol. 1, No, 2, p 111-126, September 1977. 7 fiq,
2 tab, 9 ref, 20 equ, 1 append.
Descriptors: Water measure, Flow measurement, Measurement, Flumes, Flow rates,
Hydraulic, Irrigation water, Weirs.
Presented in this paper is a set of easy-to-use formulae that give an accurate
head-discharge relationship for long-throated flumes with a prismatic throat
cross-section. The method by which the formulae have been derived is the same
for all long-throated flumes, regardless of the shape of their throat cross-
sections. As a result, the value of the discharge coefficient is independent
of this shape and is a function of the ratio of the upstream energy head over
the flume to the flow-wise length of the throat. The formulae and coefficient
values in this paper also apply to broad-crested weirs with rounded upstream
nose.
77:04A-012
BIBLIOGRAPHY ON DISCHARGE MEASUREMENT TECHNIQUES,
The Task Committee on Flow Measurement of the Committee on Hydraulic Structures
of the Hydraulics Division,
American Society of Civil Engineers, New York, New York,
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol.
103, No. HY8, p 889-903, August 1977,
Descriptors; Flow measurement, Bibliographies, Discharge measurement, Flow
rates, Irrigation, Irrigation efficiency.
The Task Committee on Discharge Measurement was authorized by the Hydraulics
Division in August 1968. The Task Committee's charge relative to flow measure-
ment included a review of techniques available, the encouragement of research
in flow measurement, and the preparation of a final report, A review of the
literature was made, resulting in the substantial bibliography which constitutes
this report.
77:04A-013
DESIGN OF IRRIGATION PIPE LATERALS WITH MULTIPLE OUTLETS,
Perold, R.P.
Division of Agricultural Engineering, Department of Agricultural Technical
Services, Stellonbosch, Republic of South Africa,
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR2, p 179-195, June 1977, 8 fig, 9 ref.
Descriptors: Irrigation, Irrigation systems, Irrigation design,. Irrigation
engineering, Hydraulics, Hydraulic design,
Design criteria for the design of multiple outlet irrigation pipe laterals are
examined and the mean deviation is recommended as the criterion, The problem
of the sloping pipe lateral design (constant diameter) can be solved precisely
by computing a series of dimensionless solutions and calculating the mean
deviation in each case, as well as the design parameters, Rs, and Hs, which
state the relation between frictional losses and gradient differences, respectively,
to the design outlet pressure. A design chart is presented from which the per*-
missible number of outlets for a given value of the mean deviation can be read,
or from which Rs can be read for a given number of outlets so that the pipe dia-
meter can be found. Suitable programs for a pocket calculator are given so
that the inlet pressure required for a particular case can be found. Programs
are also given so that the final value of the mean deviation can be checked
or the pressures at intermediate outlets determined.
167
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77:04A-014
DESIGN OF DRIP IRRIGATION SUBMAIN,
Wu, I., and Gitlin, H.M.
Hawaii University, Department of Agricultural Engineering, Honolulu, Hawaii.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR2, p 231-243, June 1977. 9 fig, 4 ref.
Descriptors: Irrigation, Irrigation systems, Irrigation design, Hydraulics,
Hydraulic design.
A submain is a part of a drip irrigation system. It is used as a control having
the following functions: (1) To control irrigation application; (2) to se-
quentially irrigate separate fields; and (3) to reduce main line pressure to the
lateral operating pressure. The design of submains is based on both capacity
and uniformity. Capacity means that submain size should be designed to deliver
the required amount of water to irrigate the field. Uniformity means that the
submain should be designed to minimize pressure variation so the flow into all
lateral lines will be nearly equal. The submain is hydraulically the same as
lateral lines having a steady spatially varied flow with equally spaced lateral
outflows. Design of the submain will be based on a study of hydraulics and
energy relations. The design chart developed for laterals can also be used for
submains, provided a set of charts is made for different possible submain sizes.
This paper presents a general design chart that can be used for different sub-
main sizes and a simplified submain chart that can be used to simplify and
speed up design. Considerations are also made for irregularly shaped fields,
77:04A-015
SEEPAGE CHARACTERISTICS OF STABLE CHANNELS,
Gill, M.A.
Ahmadu Bello University, Department of Civil Engineering, Zaria, Nigeria,
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR1, p 95-99, March 1977. 2 fig,, 4 ref.
Descriptors: Seepage, Channels, Channel flow, Channel erosion, Channel improve-
ment, Hydraulics.
Seepage characteristics of hydraulically stable channels are investigated using
the method of Zhukovsky's function. It was found that a function of the form
given in Equation 2 describes seepage characteristics of a channel whose shape
is defined by a cosine curve. This shape conforms exactly to the shape of a
hydraulically stable channel. Expressions for seepage discharge, streamlines,
and equipotential lines are obtained, and results are demonstrated graphically
for a channel in which H = 3, and B = 10 units of length.
77:04A-016
PULSE IRRIGATIONDESIGN FOR OPERATING SETS,
Karmeli, D., and Peri, G.
Colorado State University, Department of Agricultural Engineering, Fort Collins,
Colorado.
Journal of the Irrigation and Drainage Division, Proceedings of the American
Society of Civil Engineers, Vol. 103, No. IRl, p 33-41, March 1977. 1 fig, 3 tab,
1 ref.
(See 77:03F-021)
77:04A-017
ALGEBRAIC COMPUTATION OF FLOW IN BORDER IRRIGATION,
Strelkoff, T.
California University, Department of Water Science and Civil Engineering, Davis,
California.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IRS, p 357-377, September 1977, 10 fig, 6 ref.
Descriptors: Border irrigation, Surface irrigation, Model studies, Simulation
analysis, Infiltration, Irrigation design.
168
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The elements of a model of surface irrigation in a border have been presented.
A sufficient number of physical assumptions have been made to allow the phenomena
to be described by algebraic equations. This involves adaptation of simple shapes
to both the surface and subsurface profiles. The absolute value of depth at key
points in the surface profile is related to discharge through the assumption that
the depth is normal. In the subsurface profile, the depth at key points is related
to the time water has been available there for infiltration through an infiltration-
time formula.
77:04A-018
BORDER-IRRIGATION HYDRAULICS WITH ZERO INERTIA,
Strelkoff, T., and Katopodes, N.D,
California University, Water Science and Engineering Section, Land, Air and Water
Resources, Davis, California.
Journal of the Irrigation and Drainage Division, American Society of Civil Engineers,
Vol. 103, No. IRS, p 325-342, September 1977. 7 fig, 19 ref.
Descriptors: Border irrigation, Surface irrigation, Irrigation, Irrigation
practices, Irrigation systems, Irrigation engineering, Model studies.
A model of border irrigation based on the Saint-Venant equations with the accelera-
tion (.inertia) terms deleted has been constructed. For the test cases presented,
agreement with more complex (and costly) models and with experiment has been satis-
factory -
77:04A-019
HYDRODYNAMICS OF BORDER IRRIGATIONCOMPLETE MODEL,
Katopodes, N.D., and Strelkoff, T,
California University, Department of Water Science and Engineering, Davis,
California.
Journal of "the Irrigation and Drainage Division, American.Society of Civil
Engineers, Vol. 103, No, IR3, p 309-324, September 1977, 5 fig, 1 tab, 6 ref.
Descriptors: Border irrigation, Irrigation, Irrigation practices, Irrigation
systems, Model studies. Simulation analysis, Hydrodynamics, Irrigation engineering,
Surface irrigation.
The phenomenon of surface irrigation from start to finish is modeled mathematically,
using the method of characteristics. The solution, based on prescribed time in-
crements, is correct to second-order accuracy, and the iterative scheme had second-
order rate of convergence. The cost and accuracy of the model were tested against
existing field data and other models. Approximately 400 FORTRAN statements are
required for the complete code. The processing time on a Burroughs 6700 digital
computer ranges from 3 minutes to 5 minutes for a complete irrigation. At $165/hr,
this amounts to $10-$15 per run. The aim of this work was a complete hydrodynamic
model that can be trusted and operated by anyone at moderate expense. It is not
intended for design or specific applications.
77:04A-020
IMPLICATIONS OF IRRIGATION SYSTEM EFFICIENCIES,
Kruse, E.G., and Heerman, D.F.
United States Department of Agriculture, Agricultural Research Service, Fort Collins,
Colorado 80523.
Journal of Soil and Water Conservation, Vol. 32, No, 6, p 265-270, November^-
December, 1977. 32 ref.
Descriptors: Irrigation, Irrigation efficiency, Irrigation water. Irrigation
system, Irrigation engineering. Sprinkler irrigation, Surface irrigation, Furrow
irrigation, Tailwater, Water quality, Water resources, Water shortage, Water
supply, Water conservation.
Field or farm irrigation efficiencies vary greatly, depending on water supply,
type of irrigation system, crop, soil, and especially the level of management
provided by the irrigator. Sprinkler and trickle systems simplify some management
decisions by virtue of their design, at the expense of higher capital costs.
169
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Both generally have higher application efficiences than conventional surface
systems. But surface irrigation using tailwater -return facilities or level-
basin concepts, may also be efficient. Irrigation efficiency is more important
today than ever before because of limited supplies of water and energy- Irriga-
tors must look closely at attainable efficiencies of new or improved irrigation
systems if they are pumping water, if their seasonal water supplies are only
marginally adequate for crop needs, or if water lost from their systems degrades
water quality for downstream users. There are situations, however, where gravity
flow provides adequate water, and the quality of surface and subsurface return
flow equals that of the irrigation water supply. In these cases, use of water
over an entire project or river basin is a more important consideration than
irrigation efficiencies on individual farms.
77:04A-021
PERCEPTION OF ENVIRONMENTAL DAMAGE ASSOCIATED WITH IRRIGATION,
Jackson, R.H.
Brighain Young University, Department of Geography, Provo, Utah 84602.
Journal of Environmental Management, Vol. 5, No. 2, p 115-126, April 1977. 5
fig, 3 tab, 4 ref.
Descriptors: Irrigation, Irrigation practices, Irrigation effects, Salinity,
Erosion, Water conservation, Environmental effects, Environmental control.
In order to determine the level of awareness of environmental damage associated
with irrigation, questionnaires were administered to farmers and nonfarmers in
Utah Valley, Utah. The results of the survey revealed that farmers seem to be
more concerned about the damages from irrigation as determined by their volun-
tary responses to open-ended questions about irrigation damage, One-fourth
of the farmers indicated they perceived some damage from irrigation, but only
10% of the nonfarmers so responded. When asked whether they were aware of specific
damages, however, three times as many nonfarmers as farmers indicated awareness
of such damage as erosion, alkalinity, waterlogging, and so forth. Farmer percep-
tion of destruction associated with irrigation increased only slightly when asked
about specific types of damage. The level of awareness of damage for both groups
was much lower than anticipated, indicating a lack of perception of damage. Several
hypotheses are suggested to account for this low level of perception,
77:04A-022
FEASIBILITY OF INTERBASIN WATER TRANSFER,
Aron, G., White, E.L., and Coelen, S,P.
Pennsylvania State University, Department of Civil Engineering,, University Park,
Pennsylvania.
Water Resources Bulletin, Vol. 13, No, 5, p 1021-1034, October 1977. 5 figp 1
tab, 15 ref.
Descriptors: *Inter-basin transfers, *Water resources, *Alternative planning,
*Feasibility studies, *Water supply, *Flood protection, *Cost comparisons, *Reser-
voirs, Regional analysis, Economic feasibility, Hydrologic aspects, Flood control,
Low-flow augmentation, River basins, Water storage, Benefits, Costs, Equations,
Interbasin water transfer is one of the most controversial water; resources plan-
ning topics. Local communities, particularly those from which the water is to
be taken (donor regions), generate enough opposition to doom many projects to
failure. The opposition often arises because planners have traditionally considered
excess water a free commodity rather than a marketable resource. To make transfer
schemes mutually acceptable to donor and recipient regions, visible benefits must
be offered. Agreement must be made on an acceptable purchase price and/or on other
benefits such as a substantial amount of low flow augmentation or possibly some
degree of flood control on the donor source stream. The hydrologic and economic
feasibility of water transfer from the East Susquehanna River basin to the Delaware
Reservoir System for supplemental supply to the New York City area has been inves-
tigated. Nine alternative schemes for diversions up to 400 cfs and compensations
in the form of low flow augmentation and/or flood control were considered resulting
in unit costs to the recipient region between $90 and $380/mg. If only the minimum
state-mandated flow is released to the Susquehanna River, the savings to the water
recipients would be sufficient to pay a purchase price of about $21/mg, which
would be equivalent to a total amount of $420,000/year for an average export of
100 cfs.
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77:04A-023
STEADY INFILTRATION FROM A DITCH: THEORY AND EXPERIMENT
Batu, V.
Karadeniz Teknik University, Department of Civil Engineering and Architecture
Trabzon (Turkey).
Soil Science Society of America Journal, Vol. 41, No, 4, p 677-682, July-August,
Descriptors: * Infiltration, *Ditches, *Model studies, laboratory tests,
Mathematical models, Hydraulic conductivity, Flow, Steady flow. Soil water, Soil
water movement, Moisture content, Distribution patterns, Soil physics, Soil
science.
The two-dimensional, steady-state water flow equation, which is based on the
assumption that the hydraulic conductivity is an exponential function of the
soil water pressure, was solved for a ditch on the soil surface, The results
included expressions describing the distributions of matric flux potential
and water content. Measured water contents were compared with this mathematical
model and with other models.
77:04A-024
MAINLINE INSTALLATION,
Hamisch, F.
Ag Water, 22008 Riverside, Shatter, California 93263,
Drip/Trickle Irrigation, Vol. 2, No. 2, p 12, 30, 1 fig.
Descriptors: Irrigation systems, Irrigation practices, Irrigation design,
Hydraulics, Pipes, Piping systems, Pipelines.
The mainline is an integral" part of the drip irrigation system. In order for
the installed pipeline to perform properly, it must be properly designed. The
design of the pipeline has been previously discussed in the last issue and will
not be covered here. The pipeline designated must be of the proper size with
appropriate protection devices, such as pressure relief valves, vacuum relief
Valves, air release valves and check valves.
77:04A-025
EXPERIMENTAL EVALUATION OF THEORETICAL SOLUTIONS FOR SUBSURFACE DRAINAGE AND
IRRIGATION,
Tang, Y.K., and Skaggs, R.W.
North Carolina State University, Department of Biological and Agricultural
Engineering, Raleigh, North Carolina 27607.
Water Resources Research, Vol. 13, No, 6, p 957-965, December 1977, 12 fig,
3 tab, 23 ref, 15 equ.
Descriptors: Soil water, Soil water movement, Saturated flow, Drainage,
Laboratory tests, Unsaturated flow, Hydraulic conductivity, Water table,
Subsurface irrigation. Irrigation, Irrigation practices.
The Richards equation for two-dimensional saturated^unsaturated water movement
was solved for drainage and subirrigation boundary conditions by using finite
difference methods. The solutions were compared to results of experiments
conducted for various initial and boundary conditions in a large laboratory
soil tank. The soil water characteristic and hydraulic conductivity function
were measured by conventional methods and used as inputs in the numerical
solution to the Richards equation. Although predicted water table drawdown
was somewhat slower than was observed, agreement between the numerical solutions
and experimental observations was generally good. Approximate methods were also
used to characterize drainage and subirrigation and were found to be in good
agreement with solutions to the more exact Richards equation and with experimental
results when a variable drainage porosity is considered. In view of significant
field variability of soil properties and the difficulty of measuring those
properties, required by the Richards equation, it appears that simpler, approxi-^
mate methods will continue to be more useful than the exact approach for predicting
water table movement under drainage and subirrigation conditions,
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77:04A-026
OBSERVATIONS OF SOIL WATER AND SALT MOVEMENT UNDER DRIP AND FLOOD IRRIGATION
IN AN APPLE ORCHARD,
Obbink, J.G., and Alexander, D,M.
Commonwealth Scientific and Industrial Research Organization, Division of
Horticultural Research, Merbein, Victoria 3505, Australia,
Agricultural Water Management, Vol. 1, No. 2, p 179-190, September 1977. 4
fig, 3 tab, 10 ref.
Descriptors: Soil water, Soil water movement, Soil moisture, Salts, Salinity,
Saline soils. Flood irrigation, Surface irrigation, Irrigation practices.
Irrigation systems, Orchards, Apples, Crop response.
Part of a mature apple orchard, previously flood irrigated, was converted to
drip irrigation in August 1971 and maintained until May 1975, The remainder
of the orchard was irrigated as before. Annual estimates were made of moisture,
total soluble salts and chloride content of soil samples and of growth, leaf
chloride and yield of trees from the two irrigation treatments. Soil moisture
was also monitored with a neutron moisture meter. Very high salt concentrations
were observed in the various soil layers in the drip irrigation treatment. The
flood irrigation treatment had lower and less variable concentrations of salts.
Yields and chloride content of leaves sampled each January did not differ signifi-
cantly between treatments. Tree girths were smaller under drip irrigation.
The drip system, using a low pressure head, filtered water and outlets wrapped
in fiberglass, operated satisfactorily for the period of the trail,
77:04A-027
UNIFORM IRRIGATION WITH A LOW-HEAD BUBBLER SYSTEM,
Rawlins, S.L,
United States Department of Agriculture, Agricultural Research Service, United
States Salinity Laboratory, 4500 Glenwood Drive, Riverside,,California 92501.
Agricultural Water Management, Vol. 1, No, 2, p 167-178, September 1977, 8 fig,
1 tab, 3 ref.
Descriptors: Irrigation, Irrigation systems, Irrigation efficiency, Irrigation
practices. Gravitational water, Irrigation engineering, Hydraulics.
Existing closed-conduit irrigation systems are capable of saving water by increasing
application uniformity. But, because most of them require pumping to pressurize
water for distribution, the water is saved often at the expense of increased energy
consumption. This paper describes a new irrigation system that reduces the energy
requirement by using inexpensive, thin-walled, corrugated plastic pipe of suf^
ficient diameter that the pressure head often available from a surface ditch is
sufficient, A simple installation technique, giving extremely high application
uniformity, is described for the system for permanent crops. Costs for the system
can be less than for comparable sprinkler or drip irrigation systems.
77:04A-028
LATERAL FLUSHING VALVES: A GUIDE TO PLANNING, INSTALLATION, OPERATION AND MAINTE-
NANCE ,
Beth, F.
AMIAD Filtration and Irrigation Systems, M,P, Hevel, Khorazim, Israel,
Drip/Trickle Irrigation, Vol. 2, No, 1, p 27-29, January-February, 1977,
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Suspended
solids, Sprinkler irrigation, Orifices, Velocity.
There is now a well recognized need for regular cleaning of irrigation lines where
equipment with relatively small orifices is used; as with sprinklers, spray and
mist nozzles, drippers, and simple orifices. The need becomes even more critical
when the dirt load in the available water is high. The ability of a system to
flush the irrigation network is provided in the lateral flushing valve, which has
been developed during the last few years. It provides an automatic flushing
action for cleaning all the irrigation lines at least once during each irrigation
cycle.
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77:04A-029
INFLUENCE OF TRICKLE AND SURFACE IRRIGATION ON RETURN FLOW QUALITY,
Wierenga, P.J.
New Mexico State University, Department of Agronomy, Las Cruces, New Mexico
88003.
Publication No. EPA-600/2-77-093, May 1977. 158 p, 29 fig, 48 tab, 12 ref, 1
append.
Descriptors: Surface irrigation, Irrigation systems, Irrigation practices,
Return flow. Cotton, Salts, Salinity, Soil investigations, Irrigation efficiency,
Soil water, Soil moisture.
A field study was conducted to determine the effects of controlled surface ir-
rigation and trickle irrigation on the quality and quantity of irrigation
return flow. Trickle irrigation resulted in cotton yields (3-year averages)
which were 8.2 percent higher than those from the surface-irrigated plots,
and with trickle irrigation 24 percent less water was used than with surface ir-
rigation. Data on soil salt accumulation in the surface-irrigated plots showed
an increase in salt concentration with depth to the clay-sand interface. Below
the clay-sand interface at 80-100 cm, a sharp decrease in salt concentration was
observed. It appeared that a larger change in soil salinity was produced by
altering irrigation frequency than by changing irrigation efficiency. Irrigating
when 50 percent of the soil water had been depleted was the irrigation frequency
most conducive to salt retention by the soils. It appeared that trickle irriga-
tion was quite effective in controlling the volume of return flow, while main-
taining relatively low salinity levels in the soil around the trickle emitters.
Accumulated salts were readily moved away from trickle lines by heavy preplant
irrigations or intense rains.
77:04A-030
MINIMIZING SALT IN RETURN FLOW THROUGH IRRIGATION MANAGEMENT,
United States Department of Agriculturef Agricultural Research Service, United
States Salinity Laboratory, Riverside, California 92502,
Publication No. EPA-600/2-77-134, July 1977. Ill p, 43 fig, 37 tab, 23 ref,
2 append.
Descriptors: Arizona, Salts, Irrigation, Irrigation effects, Return flow,
Leaching, Alfalfa, Surface irrigation.
Two field experiments are being conducted in southwestern Arizona to investigate
the potential of reducing the salt load in irrigation return flow by decreased
leaching. Three leaching treatments of 5, 10, and 20 percent, replicated nine
times for citrus and five times for alfalfa, were established and compared with
conventional flood irrigation management,
77:04A-031
ECONOMIC ANALYSES OF MULTIPLE PIVOT IRRIGATION ON A DROUGHTY SOIL,
Otterby, M.A., and DeBoer, D.W.
Minnesota University, Department of Agricultural Engineering, Minnesota,
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-18. 4 fig, 6 tab, 8 ref.
Descriptors: Sprinkler irrigation, Crop production, Corn, Alfalfa, Economics,
Soils, Irrigation practices.
Economic analyses consisting of annual costs and returns were used to compare
the profitability of using one center pivot irrigation machine on more than one
field. Corn and alfalfa yields from an associated field study were used as a
basis for the analyses,
77:04A-032
CENTER PIVOT END SPRINKLER PATTERN ANALYSIS AND SELECTION,
Solomon, K., and Kodama, M.
Rain Bird Technical Services, Logan, Utah.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-24. 6 fig, 2 tab, 9 ref, 4 equ.
173
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Descriptors: Sprinkler irrigation, Irrigation efficiency, Irrigation engineering,
Irrigation design, Sprinklers.
Application patterns from center pivot end sprinklers are determined from
stationary distribution curves and presented in generalized form. Criteria
are defined for evaluating end sprinkler selections relative to efficient
utilization of land, water, and energy resources. Procedures are given for
relating sprinklers and machine variables with end sprinkler performance.
77:04A-033
ECONOMICS OF CENTER PIVOT END GUNS,
von Bernuth, R.D.
Rain Bird Sprinkler Manufacturing Company, Logan, Utah.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-9. 3 fig, 3 tab, 4 ref, 3 equ.
Descriptors: Sprinkler irrigation, Economics, Irrigation practices, Irrigation
engineering, Irrigation systems.
Gun type sprinklers used as "end guns" on center pivots are a popular means of
gaining additional irrigated acreage. Several economic factors which result
from using "end guns" should be considered before arriving at the conclusion
to use one.
77:04A-034
MANUFACTURING VARIATION OF EMITTERS IN TRICKLE IRRIGATION SYSTEMS,
Solomon, K.
Rain Bird Technical Services, Logan, Utah,
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-20. 4 fig, 4 tab, 9 ref.
Descriptors: Irrigation systems, Uniformity, Irrigation efficiency, Irrigation,
Irrigation practices.
Emitter manufacturing variation is shown to significantly affect trickle system
efficiencies. Values of the Coefficient of Manufacturing Variation are given
for several emission devices. Emission rate distributions are shown for typical
trickle system conditions, and are evaluated according to Emission Uniformity
and Water Storage Efficiency concepts.
77:04A-035
TRICKLE IRRIGATION: PREVENTION OF CLOGGING,
Gilbert, R.G., Nakayama, F.S., and Bucks, D.A,
United States Department of Agriculture, Agricultural Research Service, United
States Water Conservation Laboratory, 4331 East Broadway, Phoenix, Arizona 85040.
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-23. 4 fig, 3 tab, 17 ref.
Descriptors: Clogging, Irrigation, Irrigation systems, Irrigation practices,
Irrigation efficiency, Filtration, Sediment load.
Clogging of several types of trickle emitters delivering Colorado River irrigation
water to mature citrus trees was prevented by a combination of filtration and
chemical treatments, which removed suspended load, and controlled microbial slime
development and precipitation of carbonates.
77:04A-036
SELECTING THE SYSTEM FOR THE SITE,
Shearer, M.N.
Oregon State University, Department of Agricultural Engineering, Corvallis, Oregon.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 45-49, February 13-15, 1977.
17 H
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Descriptors: Irrigation, Irrigation systems, Irrigation practices. Soils, Soil
properties, Soil physical properties, Sprinkler irrigation, Infiltration, Soil
texture. Climates.
The title suggests that something about the "site" has considerable influence on
the type of irrigation system that should be installed at a specific location.
If we assume that this is true, we are confronted with the problem of identifying
those characteristics which are significant,
77:04A-037
ESTIMATING RUNOFF FROM FURROW IRRIGATION,
Ohmes, F.E., and Manges, H.L.
Garden City Branch Experiment Station, Irrigation Engineering Division, Garden
City, Kansas.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 1089-1092, December 20, 1977. 3 fig, 2 tab, 6 ref, 15 equ.
Descriptors: Furrow irrigation, Inflow, Runoff, Irrigation efficiency, Equations,
Flow rates.
Inflow into and outflow from furrows during irrigation were measured. Both theory
and field measurements have shown that runoff rate from a graded furrow can be
expressed as a function of time for the rising portion of the runoff hydrograph
and then becomes constant. Volume of runoff can be determined by integrating
the runoff equations.
77:04A-038
IMPROVED SEMI-AUTOMATIC GATES FOR CUT-BACK SURFACE IRRIGATION SYSTEMS,
Evans, R.G.
Colorado State University, Agricultural and Chemical Engineering Department,
Fort Collins, Colorado.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 105-108, 112, February 20, 1977, 7 fig, 1 tab, 12 ref.
Descriptors: Surface irrigation, Gates, Irrigation systems, Automation, Furrow
irrigation, Furrow systems, Irrigation design, Irrigation efficiency, Irrigation
practices.
One of the most effective means of improving application efficiency and uniformity
in furrow irrigation systems is the cut-back concept. The cut-back systems are
very amendable to automation, however, one of the largest obstacles to its wide-
spread use has been a lack of simple, inexpensive and reliable equipment to auto-
mate the systems, A much simplified version of a serni-automatic "'drop-open" type
of gate has been developed and its construction, field operation and reliability
are discussed in this paper. A simplified "drop-closed" type of gate is also.
discussed. Both gate types are constructed of aluminum, use mechanical Coret
timers and are interchangeable,
77:04A-039
TRICKLE AND SPRINKLER IRRIGATION OF GRAIN SORGHUM,
Ravelo, C.J., Hiler, E.A., and Howell, T.A.
Agricultural Engineering Department, Texas ASM University, College Station, Texas,
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 96-99, February 20, 1977. 5 fig, 3 tab, 18 ref.
Descriptors: Sprinkler irrigation, Crop response, Grain sorghum, Lysimeters,
Crop production, Irrigation systems, Water measurement, Water control, Water balance.
Crop response and water use efficiency (ratio of grain yield to total crop_water
use) of grain sorghum in an environmentally controlled lysimeter installation^
were investigated using trickle and sprinkler irrigation. Also, effects of dif-
ferent trickle irrigation frequencies on the crop growth and grain yield were
studied. Results indicate no significant differences in yield or water_use ef-
ficiency when using trickle and sprinkler irrigation with three irrigations per
week. Also, trickle irrigation frequencies of 1, 2, and 3 irrigations per week
appeared to have no significant effect on yield or water use efficiency of grain
sorghum on a.layered sandy loam soil.
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77:04A-040
MANAGEMENT OF BED-FURROW IRRIGATED SOIL WITH LIMITED-AND NO-TILLAGE SYSTEMS,
Musick, J.T., Wiese, A.F., and Allen, R.R,
United States Department of Agriculture, Southwestern Great Plains Research
Center, Bushland, Texas.
Transactions of the American Society of Agriculture Engineers, Special Edition,
Vol. 20SW, p 666-672, August 20, 1977. 1 fig, 4 tab, 8 ref.
Descriptors: Irrigation systems, Furrow systems, Crop production, Management,
Soil water, Irrigation water, Grain sorghum, Furrow irrigation, Cultivation.
Limited and no-tillage management in the Southern Plains can be beneficially
used in irrigated cropping systems. About 75 percent of the irrigation in this
region is by the graded-furrow method. Learning how to manage beds and furrows
between crops is essential for development of practical management systems.
This paper reports the results of 7 years of field research in developing and
evaluating limited and no-tillage management systems for irrigated crop pro-
duction.
77:04A-041
SOLAR TECHNOLOGY APPLICATIONS: A LITERATURE REVIEW OF SOLAR THERMAL POWERED
IRRIGATION SYSTEMS,
Newkirk, H.W.
California University, Technical Information Department, Lawrence Livermore
Laboratory, Livermore, California 94550.
Publication No. UCID-17510, June 1977, 18 p, 1 fig.
Descriptors: Thermal power, Power plants, Irrigation systems. Pumping plants,
Pumping.
This report is a single reference source which summarizes published information
on solar thermal powered irrigation systems. It is a compilation of literature
references and a survey of on-going work in this field. Much of the material
here outlined is tentative, rapidly changing, and highly variable in time and
place. The following information should therefore be considered a guide rather
than a set of specifications and will be updated as additional information and
references appear in the literature.
77:04A-042
CONTROL OF SEDIMENTS, NUTRIENTS, AND ADSORBED BIOCIDES IN SURFACE IRRIGATION
RETURN FLOWS,
Carter, D.L., and Bondurant, J.A.
United States Department of Agriculture, Agricultural Research Service, Western
Region, Snake River Conservation Research Center, Kimberly, Idaho 83341,
Publication No. EPA-600/2-76-237, October 1976. 45 p, 2 fig, 7 tab, 49 ref.
Descriptors: Sediments, Sedimentation, Nutrients, Return flow. Surface irrigation,
Sediment control, Erosion control, Runoff, Surface runoff, Technology, Irrigation,
Soil conservation, Pesticides, Management.
The technology available for the control of sediments, nutrients, and adsorbed
biocides in surface irrigation return flows has been reviewed and evaluated.
Some of this technology could be applied immediately to reduce sediment and
associated nutrient and biocide concentrations in surface irrigation return flows.
Much of the available information needs to be integrated to develop improved con-
trol practices. New ideas and new control technology are needed. Economic incen-
tive programs are needed to improve acceptance of control technology. The factors
controlling erosion and subsequent sediment concentrations in surface irrigation
return flows, and how these factors can be managed to reduce erosion and sediment
concentrations are reviewed and discussed.
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SECTION XVI
WATER QUANTITY MANAGEMENT AND CONTROL
GROUNDWATER MANAGEMENT (GROUP 04B)
77:04B-001
MANAGEMENT MODEL FOR GROUNDWATER DEVELOPMENT,
Willis, R., and Newman, B.A.
Cornell University, School of Civil and Environmental Engineering, Ithaca, New
York.
Journal of the Water Resources Planning and Management Division, Proceedings of
the American Society of Civil Engineers, Vol. 103, No, WR1, Proceedings Paper
No. 12953, p 159-171, May 1977. 1 fig, 3 tab, 29 ref,
Descriptors: *Groundwater resources, *Aquifers, *Mathematical models, *Water
management (applied), *0ptimization, Water supply, Economic efficiency, Water
demand, Long-term planning, Finite element analysis, Flow, Control, Wells, Pump-
ing, Equations, Systems analysis, Linear programming, Algorithms, Water resources
development.
A mathematical model for the optimal dynamic management of regional groundwater
supply resources is presented. The model, predicated upon a Galerkin finite
element formulation of flow in heterogeneous anisotropic porous media allows
management decisions to be made regarding; (1) the possible well development
sites within the groundwater basin; and (2) the optimal pumping rates needed to
meet an exogenous water demand in each planning period. The planning model
minimizes the total discounted operational costs over the planning horizon. The
algorithm solves a succession of linear programming problems obtained by linearizing
the concave objective function using a generalized Taylor series expansion about
an initial feasible decision vector. The management problem, structured as a
problem in optimal control, is solved using Tui's concave programming algorithm.
Results indicate the effectiveness of the model for the planning and development
of groundwater resources,
77:04B-002
SUBSURFACE DRAINAGE COST AND HYDROLOGIC MODEL,
Bhattacharya, A.K., Foroud, N,, Chieng, S-T,, and Broughton, R,S,
Macdonald College, Department of Agricultural Engineering, Ste, Anne de Bellevue
Quebec, Canada.
Journal of the Irrigation and Drainage Division, Proceedings of the American
Society of Civil Engineers, Vol. 103, No. IR3, p 299-308, September 1977, 4 fig,
4 tab, 7 ref.
Descriptors: *Drainage practices, *Tiles, *Water balance, *Economics, Hydrology,
Water table. Weather data, Simulation analysis, Computers, Costs, Soil water,
Effects, Frequency analysis, Mathematical models, Systems analysis,
A computer simulation water balance model was used to analyze the variation of
daily water table depths in the field using 27 years of weather data and soil
water parameters. The high water table in the study area resulted from a cool
moist climate and poor natural drainage condition. The effects of drainage^
rates and drain depths on the water table were studied, A frequency analysis
was made to obtain the recurrence intervals of specific water table depths for
various successive numbers of days. The net financial benefit from the system
was evaluated corresponding to various chances of crop failure due to inadequacy
of the drainage system during its assumed amortization period. In conclusion,
in the absence of definite functional relationships between the processes of a
soil-water-plant system, a computer simulation approach becomes valuable in pre-
dicting water table depths and their relationships to other pertinent parameters.
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77:046-003
MANAGEMENT OF GROUNDWATER AND SURFACE WATER VIA DECOMPOSITION,
Haimes, Y.Y., and Dreizin, Y.C.
Case Western Reserve University, Department of Systems Engineering, Cleveland,
Ohio.
Water Resources Research, Vol. 13, No. 1, p 69-77, February 1977. 2 fig, 1 tab,
23 ref.
Descriptors: *Groundwater, *Management, *Surface waters, *Conjunctive use,
*Methodology, Streams, Networks, Reservoirs, Optimization, Control, Water supply,
Regional analysis, Costs, Pumping recharge, Water requirements, Equations, Mathe-
matical models, Systems analysis.
Developed is a methodology for solving the problems of conjunctive use of a
large-scale complex groundwater system, a network of streams, and reservoirs
all interacting with one another. Decomposing the model of a large-scale aquifer
system as well as that of a stream network into interacting submodels provides
an improved mathematical model of the entire physical system, A theorem is
proved that establishes the necessary conditions for the existence of a solution
to the optimal control problem associated with the management of the groundwater
system. A sample problem is formulated in which the options of groundwater opera-
tions and surface water supply are conjunctively utilized to meet the water needs
of several water users in a basin; the objective function is benefit maximization.
The problem of optimal management is solved via decomposition and multilevel
approach.
77:04B-004
MINIMIZING COSTS IN WELL FIELD DESIGN IN RELATION TO AQUIFER MODELS,
Bostock, C.A., Simpson, E.S., and Roefs, T.G.
Arizona University, Department of Hydrology and Water Resources, Tucson, Arizona.
Water Resources Research, Vol. 13, No, 2, p 420-426, April 1977. 4 fig, 8 ref.
Descriptors: *Wells, *Costs, *0ptimization, *Economic efficiency, *Aquifers,
Probability, Demand, Pumping, Annual, Water table, Methodology, Decision making,
Seasonal, Groundwater, Mathematical models, Operations research.
For a given production rate from a proposed well field, well construction and
replacement costs decrease with fewer and larger wells spaced farther apart,
while pumping lift costs increase. A method for minimizing the sum of these
two costs is presented which uses a two-dimensional uniform grid of wells to
select a combination of well spacing and well capacity that minimizes costs for
a given demand. Uncertainty in field permeability at future well sites is
treated by averaging the possible outcomes over all wells in accord with a prob-
ability density function for permeability values. The method assumes an annual
cycle whereby the water table declines owing to pumping in a dry season and is
recharged to its initial state during a wet season. It is concluded that the
method is suited by Bayesian decision theory application and that it is independent
of the mathematical theory for groundwater flow used to predict aquifer response
in the aquifer cell model.
77:048-005
STATISTICAL ANALYSIS OF THE IMPACT OF GROUNDWATER PUMPAGE ON LOW^FLOW HYDROLOGY,
Fetter, C.W., Jr.
Wisconsin University, Department of Geology, Oshkosh, Wisconsin,
Water Resources Bulletin, Vol. 13, No, 2, p 309-323, April 1977. 7 fig, 1 tab,
8 ref.
Descriptors: *Pumping, *Groundwater, *Interbasin transfers, *Low flow, *Diversion,
*Wisconsin, Hydrology, Water table, Withdrawal, Forecasting, Regression analysis.
Heavy groundwater pumpage in the Yahara River basin has resulted in lowering of the
water table. As a means of preserving surface water quality, treated wastewater
was diverted from the upper basin in 1958, The two mentioned factors have acted
together to produce a depletion in Yahara River streamflow of more than 50% during
periods of low flow. Regression analyses showed that the annual 7^day and 60-day
low flows have a statistically significant correlation with mean annual flow.
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Using predictions of future mean annual discharge of the river with increasing
interbasin transfers, it was shown that by 1990 there is a significant probability
that in some years the 60-day low flow in the river will be zero. The drainage
area of the upper basin is 328 sq mi above McParland, Wisconsin.
77:048-006
SENSITIVITY ANALYSIS IN AQUIFER STUDIES,
Aguado, E., Sitar, N., and Remson, I.
Stanford University, School of Earth Sciences, California.
Water Resources Research, Vol. 13, No. 4, p 733-737, August 1977. 4 fig, 1 tab,
8 ref.
Descriptors: *Aquifers, *Management, *Planning, *Linear programming, *Groundwater,
Optimization, Wells, Discharge (water), Dewatering, Pumping, Hydraulic conductivity,
Equations, Constraints, Mathematical models, Systems analysis.
A method is presented for determining in which areas detailed knowledge of aquifer
characteristics and conditions is most critical to the success of a management
plan. These questions are answered by using sensitivity analysis to determine
how variations in parameters and input data affect the optimal -solution of a linear
programming management model. The model uses either finite element or finite dif-
ference approximations of the groundwater equations as constraints. The optimal
locations and discharge rates of wells have been determined for dewatering a rec-
tangular area to a specified level while minimizing steady state total pumping
rate and maintaining hydraulic heads in the dewatered area at or below the specified
value. The area is in a small aquifer having constant head boundaries. Sensitivity
analysis has shown that the optimal steady state solution is most sensitive to
hydraulic conductivity at and near the aquifer boundaries parallel to the length
of the dewatered area. Thus field exploration and testing should be concentrated
on determination of hydraulic conductivity in those areas,
77:04B-007
OBSERVATION WELL RESPONSE TIME AND ITS EFFECT UPON AQUIFER TEST RESULTS,
Black, J.H., and Kipp, K.L., Jr.
Institute of Geological Sciences, London (England),
Journal of Hydrology, Vol. 34, No. 3/4, p 297-306, August 1977. 3 fig, 2 tab,
5 ref.
Descriptors: *0bservation wells, *Time lag, *Aquifer testing, *Pumping, Aquifer
characteristics, Equations, Mathematical studies, Curves, Graphical analysis,
Theis equation, Water levels, Water wells, Transmissivity, Storage coefficient,
Drawdown, Hydraulic conductivity.
The concept of observation-well response time was introduced in the context of
aquifer pump tests. Previous work on hydrostatic time lag and slug tests was
considered together with the precise way in which an observation well responds
during an aquifer test. Using the concepts of Hvorslev, an equation was produced
linking observation-well response time, alpha, and a dimensionless response-time
factor beta. The Theis equation was modified by various values of beta to derive
a set of type curves. The 2 parameters - alpha and beta were related by a simple
equation involving aquifer transmissivity, T, and storativity, S, Both alpha
and beta can be obtained independently from a slug test, while alpha alone can
be obtained independently from a slug test. An example was given showing the
effect of beta upon aquifer test results, and the value of alpha calculated from
the aquifer test analysis was corroborated by slug test results. The definition
of beta was used to show in what circumstances it will be important and how its
effect can be reduced to a minimum. The introduction of slug testing of obser-
vation wells as standard practice for all aquifer tests was suggested.
77:048-008
AN ARCHETYPAL LINEAR PROGRAMMING MODEL FOR OPTIMAL INTERTEMPORAL ALLOCATION OF
GROUNDWATER TO AGRICULTURAL ACTIVITIES,
Weisz, R.N., and Towle, C.L., Jr.
Arizona University, Department of Agricultural Economics, Tucson, Arizona.
Water Resources Bulletin, Vol. 13, No. 5, p 1035-1046, October 1977. 3 fig, 2
tab, 20 ref.
179
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Descriptors: *Groundwater, *Water allocation (policy), *Linear programming,
*Economic efficiency, *Planning, Simulation analysis, Constraints, Aquifers,
Discount rates. Equations, Mathematical models, Systems analysis, Optimization,
Water utilization, Water supply.
In the past, researchers have applied a variety of analytical techniques for
maximizing the present value of a stock resource: simulation, calculus of
variations, stochastic dynamic programming, and optimal control theory. Pre-
sented herein is a more operational approachlinear programming. A simplified,
broadly drawn example from Southwest agriculture is used for demonstrating
the model structure and output; the method is based on a set of state transfor-
mation operations that prevent the additivity assumption of linear programming
from being violated. The test case concerns a geologically isolated aquifer
wholely managed by one entity (for example, the farmer) who must maximize
benefits over a two-year planning period. A comparison is made of the simulation
run with that of optimization. The archetypal linear programming model for
maximizing the present value of net benefits from a groundwater stock resource
is proven over a range of realistic parameter values. It should find innumerable
applications in the economic analysis of Southwest agricultural problems in
areas where basin-wide management of a groundwater resource is appropriate.
77:04B-009
MANURE MANAGEMENT IN AN IRRIGATION BASIN RELATIVE TO SALT LEACHATE TO GROUNDWATER,
Pratt, P.P., Davis, S., and Laag, A.E.
California University, Department of Soil Science, Riverside, California 92521.
Journal of Environmental Quality, Vol. 6, No, 4, p 397-402, October-December 1977.
7 fig, 2 tab, 10 ref.
Descriptors: Leaching, -Cations, Root zone, Manure, Irrigation, Irrigation
practices, Calcium, Magnesium, Potassium, Sodium, Salinity.
The leaching of cations from the soil root zone as a function of rate of manure
and irrigation treatments, which controlled the leaching fraction and the volume
of leachate, was measured during a 4-year field experiment. Large amounts of
Ca, Mg, and K were accumulated in the soil, but there was a net loss of Na.
Practically no K moved beyond the 1.5 m depth, which was considered the bottom
of the root zone. The percent leaching of the cations added in water and in
manures decreased as the rate of manure increased,
77:046-010
INTEGRODIFFERENTIAL EQUATIONS FOR SYSTEMS OF LEAKY AQUIFERS AND APPLICATIONS 3,
A NUMERICAL METHOD OF UNLIMITED APPLICABILITY,
Herrera, I., and Yates, R.
Universidad Nacional Autonoma de Mexico, Institute de Investigaciones en Matematicas
Aplicadas y en Sistemas, Mexico 20, Distrito Federal, Mexico,
Water Resources-Research, Vol. 13, No, 4, p 725-732, August 1977. 6 fig, 15 ref,
41 equ.
Descriptors: Aquifers, Aquifer management, Aquifer systems, Aquifer testing,
Mathematics, Mathematical studies, Groundwater.
The integrodifferential equation formulation of leaky aquifer mechanics is used
to develop a numerical method of unlimited applicability based on the finite
element technique. This approach reduces the dimensionality of the problem and
effectively uncouples the equations corresponding to each of the aquifers. Thus
the number of nodes required and the bandwidth of the matrices involved are signifi-
cantly reduced. Consequently, storage and computer time are decreased by a factor
greater than 30 in axially symmetric problems and by a considerably greater fac-
tor in the absence of such symmetry.
77:048-011
INJECTION/EXTRACTION WELL SYSTEMA UNIQUE SEAWATER BARRIER,
Sheahan, N.T.
Brown and Caldwell, Pasadena, California.
Ground Water, Vol. 15, No. 1, p 32-50, January-February, 1977, 12 fig, 10 ref.
180
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Descriptors: *Saline water intrusion, *Injection wells, *Groundwater barriers,
*California, Wells, Water wells, Groundwater recharge, Aquifers, Sea water,
Salinity, Irrigation, Waste water disposal, Artificial recharge, Groundwater,
Hydrology.
A multiple-aquifer system in the bayfront area of Palo Alto, California, is being
intruded with seawater from San Francisco Bay, In order to combat this potential
degradation of the groundwater supplies in the area, a sea water intursion bar-
rier is being constructed, consisting of a series of injection wells used to in-
ject 2.0 million gallons per day (7.6 million liters per day) of reclaimed waste-
water into a shallow aquifer. The injected water is subsequently removed by a
similar system of extraction wells to avoid any possible degradation of the
water supply aquifers from this source and to allow reuse of the reclaimed waste-
water. The investigation phase included test drilling, aquifer testing, and
injection testing to determine the feasibility of the injection/extraction (I/E)
concept. The number, spacing, and location of I/E doublets were optimized by
using a digital computer model. The double-cased, doubles-screened wells were con-
structed, using corrosion-resistant materials, and the wells were designed for
ease of routine maintenance. In operation, injection and extraction will be
computer controlled by sensing piezometric levels in a series of monitor wells.
Water pumped from the extraction wells will be sold for industrial and agricul-
tural purposes. The I/E well system has been approved for Federal and State
grand funding.
77:O4B-012
A HIERARCHY OP RESPONSE FUNCTIONS FOR GROUNDWATER MANAGEMENT,
Dreizin, Y.C., and Haimes, Y.Y.
Mekoroth Water Company, Systems Engineering Department, Tel-Aviv (Israel).
Water Resources Research, Vol. 13, No. 1, p 78-86, February 1977. 5 fig, 4 tab,
20 ref.
Descriptors: *Groundwater, *Management, *River basins, *Aquifers, *Linear pro-
gramming. Pumping, Recharge, Streams, Stress, Ohio, Input^output analysis,
Simulation analysis, Methodology, Behavior, Hydraulics, Mathematical models,
Equations, Systems analysis.
6
The physical system dealt with in this paper is a river basin with multiunit
aquifers and interconnected streams. The problem is how to model this complex
system and then to represent it in terms of its response to stress in the form
of pumpage and recharge. The system responds to pumpage in two ways: as draw~
down or as flow between streams and aquifers. A hierarchy of linear mathematical
models for a large-scale physical system response to stress has been developed.
For the system response, an explicit mathematical expression is used to couple
the physical system with the formulation of a management model, The models developed
herein have been successfully tested on a case study o£ the Fairfield-New Baltimore
area at the lower part of the Great Miami River in southwestern Ohio.
77:046-013
FIELD-MEASURED WATER UPTAKE OF SUDANGRASS ROOTS AS AFFECTED BY FERTILIZATION,
Fluhler, H,, Ardakani, M.S., Szuszkiewicz, I.E., and Stolzy, L.H.
California University, Riverside, California.
Agronomy Journal, Vol. 69, No. 2, p 269-274, March-April, 1977, 8 fig, 23 ref,
11 equ.
Descriptors: Fertilizers, Fertilization, Groundwater, Nitrates, Leaching, Roots,
Evapotranspiration, Groundwater resources, Water quality control.
Cultural practices could affect the flow of water and solutes toward groundwater,
In this field experiment we analyzed the effect of fertilization on water uptake
of sudangrass and its indirect influence on deep drainage and nitrate leaching,
Root water uptake was calculated as sink term in the continuity equation using
successive measurements of water content and matric potential profiles in con-
nection with field measured hydraulic conductivity functions. The experiment
was conducted in three field plots on Hanford fine sandy loam. Fertilization .
increased dry matter production and water uptake significantly and reduced deep_
drainage and nitrate leaching. Water uptake patterns and root length distribution
181
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was not correlated. Mainly due to fertilization with nitrate nitrogen, the
evapotranspiration approximated the amount of irrigation water applied. These
results indicate that optimum water and fertilizer use and minimum groundwater
pollution per unit crop production are intimately linked together.
77:04B-014
PREDICTING PHOSPHATE MOVEMENT THROUGH SOIL COLUMNS,
Sawhney, B.L.
Connecticut Agricultural Experiment Station, New Haven, Connecticut.
Journal of Environmental Quality, Vol. 6, No, 1, p 86-89, January-March, 1977.
5 fig, 21 ref.
Descriptors: Groundwater, Phosphorus, Soils, Soil investigations, Soil properties,
Waste water, Sorption,
To assess the potential pollution of groundwater with P from septic tank drain-
fields, sorption capacities of various soils were determined over an extended
period of time and related to P movement through soil columns using solutions
having P concentrations similar to waste waters, The amounts of P sorbed by
fine sandy loam Cfsl) and silt loam Csil) soil columns before breakthrough oc-
curred were approximately equal to the sorption capacities determined from iso-
therms obtained over a sufficiently long reaction time of about 200 hours. In
Merrimac fsl, breakthrough occurred after about 50 pore volumes of waste water
had passed through the column while about 100 pore volumes passed through Buxton
sil before the breakthrough occurred. Following breakthrough, concentration of
P in the effluent continued to increase and approached the influent concentration
after several hundred pore volumes of effluent had passed through the columns.
The results, thus, suggest that while most deep soils should effectively remove
P from waste water, groundwater under drainfields installed in soils of low P
sorption capacity after prolonged use may contain undesirably large concentrations
of P.
77:048-015
POSSIBLE ENERGY SAVINGS IN IRRIGATION,
Gilley, J.R., and Watts, D.G.
Nebraska University, Department of Agricultural Engineering, Lincoln, Nebraska.
American Society of Civil Engineers Journal of the Irrigation and Drainage
Division, Vol. 103, No. IR4, p 445-457, December 1977, 3 fig, 6 tab, 20 ref,
2 append.
Descriptors: *Irrigation practices, *Irrigation efficiency, *Pumping, Energy,
Sprinkler irrigation, Water reuse, Center pivot systems, Water pressure, Farm
equipment, Fertilizers, Nitrogen compounds, Nebraska,
Studies in Nebraska have shown that over 40% of all the energy consumed by
duction agriculture is used for pumping water from wells, which supply about
80% of the irrigation water requirements. Reduction of energy used in irrigation
pumping would thus have significant impact. Six procedures, utilized singly
or in various combinations, show strong energy-saving potential: (1) increased
irrigation efficiencybetter design and management of center pivot and surface
systems; greater use of trickle, subsurface, runoff reuse systems as rising
fuel prices make them cost effective; (2) improved pumping plant efficiency;
(3) reduced water pumping--advances in irrigation scheduling; (.4). lowering
pressure of sprinkler systems; (.5) scheduling to decrease electric peak demand,
and; (6) minimizing nitrogen fertilizer losses due to deep percolation-^-fertilizer
is conserved through irrigation scheduling, thus conserving the energy used in
its manufacture. Energy savings of 40%-50% are considered attainable through
these procedures.
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SECTION XVII
WATER QUANTITY MANAGEMENT AND CONTROL
WATERSHED PROTECTION (GROUP 04D)
77:040-001
GULLY WALL STABILITY IN LOESS-DERIVED ALLUVIUM,
Bradford, J.M., and Piest, R.F,
Agricultural Research Service, Columbia, Missouri.
Soil Science Society of America Journal, Vol. 41, No. 1, p 115-122, January-
February, 1977. 7 fig, 3 tab, 13 ref,
Descriptors: *Soil strength, *Gully erosion, Soil mechanics, Loess, Erosion,
Tensiometers, Piezometers, Slope stability, Groundwater, Sedimentation, On-
site investigations, Water pollution,
A field study was made on an instrumented vertical slope to investigate the
triggering mechanisms that initiate gully wall failure in loess-derived allur-
vium. The relevance of hydrology, soil morphology, and soil mechanisms to an
understanding of gully slumping was examined. Conventional limit equilibrium
slope stability methods were of little value in predicting failure vo.lumes or
in understanding the failure mechanics. The geometry and time of failure were
greatly influenced by the structural features of loess-derived alluvium and
by the dependence of the shear strength on the pore water pressure within the
soil.
77:040-002
AREAWIDE WATER QUALITY MANAGEMENT IN AN ENERGY DEVELOPMENT AREA,
Judy, C.H., and Gartner, A.
Yellowstone-Tongue A.P.O., Post Office Box 503, Broadus, Montana 59317,
Water Resources Bulletin, Vol. 13, No. 4, p 835-841, August 1977. 1 fig, 2 tab,
5 ref.
Descriptors: Water quality, Water quality management, Energy, Watersheds, Water-
shed management.
A Section 208, Areawide Waste Treatment Management Project, is attempting to develop
an implementable water quality management plan for an energy impacted area. Staff
members and consultants are investigating point and nonpoint sources. On a short-
term basis, population growth and construction will have a greater impact on water
quality than strip mining.
77:040-003
DRAIN DISCHARGE FROM A LEVEL AGRICULTURAL WATERSHED,
Sharma, T.C., and Irwin, R.W,
Guelph University, School of Engineering, Ontario, Canada.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR4, Proceedings Paper 13399, p 429-443, December 1977,
7 fig, 3 tab, 12 ref.
Descriptors: *Drainage, *Agricultural watersheds, *Discharge (water), Drainage
patterns (geologic), Hydraulic conductivity, Hydrography, Hydrology, Model studies,
Surface runoff, Tile drainage, Watersheds (basins), Subsurface drainage.
A hypothesis was developed that watershed discharge from rainfall, for nonfreezing
periods from a tile drained level watershed, was mainly tile flow with negligible
amounts of surface runoff and base flow. Daily discharges at the watershed out-
let were due to depletion of 2 parallel linear reservoirs. A fast reacting
183
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reservoir, represented by the physical shallow plowed layer, constituted nearly
40% of the total runoff volume. The slow reacting reservoir, represented by the
subsoil zone, contributed nearly 60% of the total runoff volume.
77:040-004
SEDIMENT DEPOSITION PATTERNS IN SIMULATED GRASS FILTERS,
Tollner, E.W., Barfield, B.J., Vachirakornwatana, C,, and Haan, C,T.
Kentucky University, Department of Agricultural Engineering, Lexington, Kentucky.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 5,
p 940-944, September-October, 1977. 9 fig, 1 tab, 10 ref.
Descriptors: *Deposition (sediments), *Grasses, *Grassed waterways, *Model studies,
Mathematical models, Hydraulic models, Laboratory tests, Filters, Sediments,
Sediment transport, Sediment load, Sedimentation.
The principle of mass continuity was used to develop equations to predict the rate
of advance of a sediment deposition front in a grass filter under steady-state
flow conditions. Based on the theoretical analysis, it was shown that the rate
of advance is proportional to the square root of elapsed time until the depth of
deposition reaches the grass height and then ^linearly proportional to elapsed
time. The validity of the equations was evaluated in cylindrical and flat bladed
artificial media using homogeneous sediment. The agreement between predicted and
observed values was excellent.
77:O4D-005
SEDIMENT FROM DRAINAGE SYSTEMS FOR CLAY SOILS,
Schwab, G.O., Nolte, B.H., and Brehm, R,D.
Ohio State University, Department of Agricultural Engineering, Columbus, Ohio.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 5,
p 866-872, September-October, 1977. 3 fig, 2 tab,.10 ref.
Descriptors: *Sediment yield, *Drainage systems, *0hio, *Clays, Tile drainage,
Surface drainage, Soils, Measurements, Testing procedures, On-site tests, On-
site investigations. Runoff, Agriculture, Irrigation, Rainfall, Crops, Corn
(field), Oats, Alfalfa, Land management.
Sediment losses from tile and surface drainage systems in a lakebed soil in
northern Ohio were measured for 6 years (1969-1974). Average annual losses were
2359 kg/ha from tile only and 3687 kg/ha for surface only. Calculated losses
for the combination tile and surface drainage system were 2672 kg/ha. Annual
measured losses ranged from about 100 to 9000 kg/ha. Average net losses from
sprinkler irrigation were negligible, and usually more sediment was added than
removed in the drainage water. Sediment concentration in tile flow from irriga-
tion increased significantly with the antecedent soil moisture content. Concen-
trations were high at the beginning of flow but decreased to a nearly constant
level after 20 hr, A possible explanation for the high concentrations is that
the sediment moved in suspension with the water and not necessarily through the
soil cracks. Estimates using a rainfall factor in the universal soil loss equa^-
tion for surface drainage were 89% of the measured losses with an r sq value of
0.25, significant at the 99% level. Estimates using a runoff factor were 74% of
the measured losses with an r sq value of 0.35, also significant at the 99%
level.
77:040-006
SEDIMENT YIELD PREDICTION BASED ON WATERSHED HYDROLOGY,
Williams, J.R., and Berndt, H.D.
Agricultural Research Service, Temple, Texas.
American Society of Agricultural Engineers, 1976 Winter Meeting, Chicago, Illinois,
December 14-17, 1976. Paper No. 76-2.535. 14 p, 3 tab, 12 ref.
Descriptors: *Sediment yield, *Forecasting, *Hydrology, Watersheds (.basins),
Reservoir design, Model studies, Runoff, Computers, Erosion, Equations, Farm
management, Erosion control, Costs, Curves, Soil moisture, Peak discharge.
A model for predicting sediment yield from ungaged watersheds was developed by
attaching a sediment yield model to hydrologic models. The sediments-runoff model
is useful in reservoir design and water quality modeling because daily, monthly,
and annual sediment yield can be predicted with simple inputs and low computer costs,
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77:040-007
PREDICTION OF VELOCITY DISTRIBUTION IN A VORTEX TUBE SEDIMENT TRAP WITH TURBULENCE
MODELS,
Edling, R.J., Barfield, B.J., and Haan, C.T.
Nebraska University, Panhandle Station at Scottsbluff, Nebraska.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 2,
p 301-308, March-April, 1977. 5 fig, 2 tab, 16 ref.
Descriptors: *Sediment control, *Sediments, *Vortices, *Model studies, Mathemati-
cal models, Velocity, Flow, Sediment transport, Fluid mechanics, Hydraulics, Open
channels, Distribution patterns. Rotational flow, Turbulence.
Meaningful investigation into the potential and limitations of the vortex tube
sediment trap could be accomplished theoretically if prediction of velocity pro^
files were possible. Empirical and semi-empirical velocity prediction techniques
were tested. In the empirical technique, constants combining values for mean
flow velocity, wall velocity, and vortex perimeter velocity were applied; whereas
in the semi-empirical technique, a two equation turbulence kinetic energy and
dissipation was applied. Prediction models were tested experimentally. Results
revealed a range in constants for the empirical technique which indicated that
the method could only be used as a guide, The semi-empirical prediction values
approximated measured velocity values,
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SECTION XVIII
WATER QUALITY MANAGEMENT AND PROTECTION
IDENTIFICATION OF POLLUTANTS (GROUP 05A)
77:05A-001
A NOTE OF PLEXIGLAS HS FLUMES,
Robinson, W.H., Jr., and Wright, M.E.
Virginia Polytechnic Institute and State University, Department of Agricultural
Engineering.
Water Resources Research, Vol. 13, No. 1, p 211-212, February 1977. 4 fig, 1 ref.
Descriptors: *Water measurement, Instrumentation, *0pen channels, Flumes,
Hydraulics, Discharge (water), Effluents, Calibrations, Specifications, Low flow,
Industrial plants, Pollutant identification.
H flumes are convenient devices for accurate measurement of open channel flows,
especially if trash is present. Several of the HS (smaller) types were constructed
of plexiglas and used successfully in a commerical plant to measure effluents
from vegetable washers. Lumped data from the calibration of three flumes were
fitted to a curve of the form y=a(x to the b power). The correlation coefficient
R squared for observed versus calculated values was 0.998. A 99% confidence band
fitted to the prediction curve was very narrow, indicating the high degree of
accuracy of the device.
77:05A-002
CHEMICAL REDUCTION OF NITRATE BY FERROUS IRON,
Buresh, R.J., and Moraghan, J.T.
North Dakota State University, Department of Soils, Fargo, North Dakota.
Journal of Environmental Quality, Vol. 5, No. 3, p 320-325, July-September, 1976.
5 fig, 4 tab, 30 ref.
Descriptors: *Nitrates, *Denitrification, *Nitrogen, Chemical reactions, Chemi-
cals, Iron, Air pollution, Pollutant identification.
Knowledge concerning the chemical reduction of N03(-) to gaseous products, a pro-
cess of potential practical significance as an antipollution device, is sparse.
The influence of pH on chemical reduction of N03(-)-N (approximate concentration
23 ppm) by Fe(2+) in the presence and absence of Cu(2+) was studied over a pH
range from 6 to 10. After 24 hours of controlled pH incubations under a helium
atmosphere N03(-), N20, NO, N2, and NH4(+) were determined. The initial Fe(2+)/
N03(-) mole ratio was 8. Reduction of N03(-) was negligible in the absence of Cu
(2+), but was pronounced above pH 7 in the presence of approximately 5 ppm Cu(2+).
Formation of HN4(+) increased with pH and was the dominant process at pH 9 and 10.
Nitrous oxide and N2 accumulations were greatest in the pH range from 8 to 8.5 and
negligible at pH6 and 10. Nitrite formation was small except at pH9 and 10.
Trace quantities of NO accumulated during incubation if the pH was allowed to drop
below 6. Levels of Cu(2+) and Fe(2+) influenced the extent and nature of N03(-)
reduction at pH8. Maximum reduction of NO3(-) (93%) and maximum gas production,
equivalent to 61% of the original N03(-), occurred when the Fe(2+)/NO3(-) mole
ratio was 12 and the Cu(2+) level was approximately 10 ppm. The N20/N2 mole
ratio in the evolved gases decreased as the Cu(2+) level was increased from
approximately 1 to 10 ppm and as the Fe (2+)/N03(-) mole ratio was increased from
8 to 12. Nitrate was relatively stable at a Cu(2+) content of 0.1 ppm irrespective
of the Fe(2+)/N03(-) ratio.
77:05A-003
USE OF LABORATORY EXTRACTION DATA TO PREDICT LOSSES OF DISSOLVED INORGANIC
PHOSPHATE IN SURFACE RUNOFF AND TILE DRAINAGE,
Sharpley, A.N., Tillman, R.W., and Syers, J.K.
Massey University, Department of Soil Science, Palmerston North ,(New Zealand).
186
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Journal of Environmental Quality, Vol. 6, No. 1, p 33-36, 1977. 4 fig, 2 tab
14 ref. '
Descriptors: *Phosphorus, *Subsurface runoff, *Measurement, laboratory tests,
*Pollutant identification, *Phosphates, *Dissolved solids, Surface runoff,
Analytical techniques, Pastures, Tile drainage, Fertilization, Foreign research.
A laboratory procedure is described which measures extractable soil inorganic
phosphorus to predict losses of dissolved inorganic phosphorus (DIP) in surface
runoff and subsurface tile drainage from a soil under permanent pasture in both
fertilized and unfertilized conditions. The mean DIP concentration in each of
several surface runoff periods was closely correlated with the amounts of inorganic
phosphorus extracted by 0.1M sodium chloride from the top 5 cm of soil prior to
the period. For three of the four combinations of treatments evaluated (undrained,
unfertilized; drained, unfertilized, and drained, fertilized) the linear relation-
ships obtained were similar despite large variations in the phosphorus concentrations
observed. Mean DIP concentrations in surface runoff from the drained plots were
consistently lower than those from the undrained plots. The relationship between
the mean DIP concentrations of surface runoff and the amounts of extractable
inorganic phosphorus for the undrained, fertilized plot was also linear but a
greatly different gradient was obtained. Soil extraction data appear to be
useful in predicting mean DIP concentrations in surface runoff from reasonably
homogeneous soils under pasture. Total DIP loading correlated best with the
amounts, of inorganic phosphorus extracted from soil at 40-50 cm, a depth which
corresponds to that of mole channels.
77:05A-004
IRRIGATION RETURN FLOW PROBLEMS IN YAKIMA VALLEY,
Spencer, J., and Horton, M.
State of Washington, Department of Ecology, Olympia, Washington.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 299-306, May 16-19, 1977.
2 fig, 5 ref.
Descriptors: Return flow, Agriculture, Sediments, Phosphates, Nitrates, Water
management (applied), Water quality, Irrigation, Soils, Washington.
Studies completed in recent years show that irrigated agriculture is a significant
source of the pollutants in the lower reaches of the Yakima River. Sediments,
phosphates and nitrates are the principal pollutants resulting from irrigation
activities. Improved on-farm water mangagement practices should be undertaken to
alleviate this water quality degradation. Since the passage of P.L. 92-500,
attempts to apply NPDES permits to irrigation return flows have been stymied by
legal questions and a lack of knowledge of relationships between farming practices,
soils, weather conditions, and water quality. In addition, there are legal
questions regarding the authority of irrigation districts in the State of
Washington to control on-farm water management practices.
77:05A-005
THE HYDRO-SALINITY SYSTEM IN THE GRAND VALLEY,
Walker, W.R., Skogerboe, G.V-, Evans, R.G., and Smith, S.W.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 361-367, May 16-19, 1977.
7 fig, 3 tab, 13 ref.
Descriptors: Colorado, Colorado River, Salinity, Salts, Groundwater, Return flow,
Seepage, Deep percolation.
The Grand Valley hydro-salinity system is described by research data collected over
an eight-year period. A review of previous estimates indicates the great vari-
ability that can be expected when data are few and of poor quality. The Grand
Valley system contributes approximately 630,000 metric tons of salts to the river
annually. This figure represents 78 metric tons of salt per hectare-meter_of water
reaching the underlying groundwater aquifer from irrigation return flows with
187
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canal and ditch seepage contributing 23 percent of the salt pickup, lateral seepage
32 percent, and on-farm head ditch seepage and deep percolation losses contributing
the remaining 45 percent of the salt pickup.
77:05A-006
TOXIC METALS IN GROUNDWATER OF THE FRONT RANGE, COLORADO,
Klusman, R.W., and Edwards, K.W.
Colorado School of Mines, Department of Chemistry, Golden, Colorado.
Ground Water, Vol. 15, No. 2, p 160-169, March-April, 1977. 6 fig, 7 tab, 14
ref.
Descriptors: *Heavy metals, *Groundwater, *Colorado, Trace elements.
Water quality, Cadmium, Copper, Iron, Lead, Manganese, Mercury, Zinc, Hydrogen ion
concentration. Oxidation-reduction potential. Specific conductivity, Distribution,
Mineralogy, Plumbing, Water pollution, Geochemistry.
A study of toxic trace metal distribution in groundwaters of the Front Range mineral
belt, Colorado, and adjacent areas was performed in order to determine the relation-
ship of water quality to mineralization and to determine the magnitude of potential
health effects. A total of 149 samples was collected and analyzed for arsenic,
cadmium, copper, iron, lead, manganese, mercury, silver, and zinc. Field deter-
minations of pH, Eh, and specific conductance were also made. The trace element
data exhibited a lognormal distribution and were described utilizing the geometric
mean and geometric deviation. Four populations were recognized in the samples: (1)
samples in the mineral belt with plumbing contamination; (2) samples in the mineral
belt without plumbing contamination; (3) samples outside the mineral belt with
plumbing contamination; and (4) samples outside the mineral belt without plumbing
contamination. Differences in these populations for several elements were observed
utilizing the t test. Groundwaters in the mineral belt are estimated to exceed
the U.S. Public Health Service limit in 14% of the samples for Cd, 1% for Cu, 51%
for Fe, 74% for Mn, 2% for Hg, and 9% for Zn. Groundwaters outside the mineral
belt have similar probability of exceeding the limit for Hg and lesser probabi-
lities for all other elements.
77:05A-007
GROUNDWATER CHEMICAL QUALITY MANAGEMENT BY ARTIFICIAL RECHARGE,
Nightingale, H.I., and Bianchi, W.C.
Agricultural Research Service, Fresno, California.
Ground Water, Vol. 15, No. 1, p 15-21, January-February, 1977. 6 fig, 5 tab, 17
ref.
Descriptors: *Groundwater recharge, *Artificial recharge, *Water quality, *Cali-
fornia, Monitoring, Recharge ponds, Pit recharge, Groundwater, Groundwater move-
ment, Chemicals, Nitrates, Salinity, Salts, Conductivity.- Specific conductivity,
Wells, Water wells, Sampling.
The effectiveness of basin groundwater recharge at the Leaky Acres Recharge
Facility in Fresno, California, for improving the regional groundwater quality
was studied as 65,815,000 cu m of high quality surface water was recharged from
1971 through 1975. Observation wells at the facility showed some variability
in chemical parameters associated with each recharge period. The long-term
decreased in salinity could be described by a power law decay curve fitted by
regression analysis. Without a special network of observations wells outside
the facility, scientific evaluation of the enclave of recharged water is not
possible. A practical evaluation of water quality changes is possible from
producing water wells around the facility. However,- the pumping well discharge
time variations, well depth, aquifer sequence, and prior use of surrounding land
must be considered, since all of these factors affect the pumped-water quality
and its seasonal variability. Recharge at Leaky Acres had noticeably decreased
the groundwater salinity for a distance of up to 1.6 km in the direction of the
regional groundwater movement.
77:05A-008
NO SIMPLE ANSWERS ON SALINITY,
McNeill, E.
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Irrigation Journal, Vol. 26, No. 6, p 16-18, November-December, 1977. 5 fig.
Descriptors: Salinity, Saline water. Saline soils, Water quality. Water quality
control, Salts.
Salinity control is the most critical problem facing agricultural irrigation mana-
gers in the arid Western states, according to opinions of water specialists before
a late September conference on Salt and Salinity Management at the Miramer Hotel
in Santa Barbara, California. To search for solutions on how to manage agri-
cultural lands served by irrigation waters containing an increasing build-up of
salts, some 150 professionals in the management, government and educational fields
met at the two-day conference to hear and study the findings of an extensive group
of authoritative speakers who have actively worked on the problem.
77:05A-009
EVALUATION OF A NITRATE-SPECIFIC ION ELECTRODE,
Yu, K.Y., and Berthouex, P.M.
California University, Environmental Engineering Program, Los Angeles, California.
Journal Water Pollution Control Federation, Vol. 49, No. 8, p 1869-1901, August
1977. 1 fig, 9 tab, 7 ref.
Descriptors: *Pollutant identification, *Electrodes, *Analytical techniques,
*Permselective membranes, *Nitrates, *Electrochemistry, Water chemistry, Aqueous
solutions, Chemical properties, Chemical potential. Electrical equipment, Model
studies, Chemical Analysis, Waste water treatment, Brucine method.
The Simple Electrode and the Standard-Addition Electrode methods are used to
evaluate nitrate determinations with a nitrate-specific ion electrode and the
Brucine method using effluent samples from biological treatment units. The
nitrate electrode measures nitrate activity in terms of potential across a layer
of water-immiscible ion exchanger held in place by an inert porous membrane.
Electrode behavior follows a Nernst relation within the working range. Ionic
interference is usually counteracted by the addition of a buffer to maintain
constant ionic strength. The Standard-Addition or Known-Increment method in-
volves the addition of a known amount of nitrate to a solution containing an
unknown amount. The quantity of nitrate present in the initial solution is deter-
mined by measuring the change in potential produced by the additional nitrate.
Grab samples of waste water effluent with nitrate concentrations ranging from
2-20 mg/liter were collected from nitrification pilot plants. Higher readings
obtained with the Simple Electrode method than with Standard-Addition were attri-
buted to greater influence of high hardness and alkalinity in the waste water
on simple electrode determinations. Standard errors for nitrate determinations
with the Brucine method were higher than for either electrode method, and proce-
dures were more time-consuming, requiring reagent preparation. The specific-
nitrate ion electrode is- recommended as a relatively inexpensive, fast, portable
means of nitrate determination in waste water for concentrations as low as 1
mg/liter nitrate-N.
77:05A-010
A MICRO-KJELDAHL TECHNIQUE FOR NITROGEN DETERMINATION IN WATER, WASTEWATER, AND
SLUDGE,
Stephenson, R.L.
Butler, Fairman and Seufert, Incorporated, Carmel, Indiana.
Journal Water Pollution Control Federation, Vol. 49, No. 12, p 2499-2502, December
1977. 2 tab, 5 ref, 1 append.
Descriptors: *Nitrogen, *Ammonia, *Amino acids, *Acids, *Ammonium compounds,
Testing procedures, Analytical techniques, Measurements, Nitrogen compounds,
Nitrification, Application methods, Methods, Waste water treatment.
A modification of the micro-Kjeldahl technique was developed as a simplified method
of measuring the nitrogen content in waste water, sludge, and water. A 5-ml sam-
ple containing ammonia nitrogen is subjected to a temperature of 340C, producing
ammonium bisulfate and ammonium sulfate. The sample is diluted after digestion
with ammonia-free water and its pH is raised to 10 with the addition of sodium
hydroxide. The nesslerization technique is used to calculate the ammonia nitrogen
concentration in the sample. The simplified technique was tested in laboratory
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experiments with four representative amino acids: glycine, methionine, tryptophan,
and diphenylcarbazone. The nitrogen concentration of the samples were 500, 250,
50, and 10 mg/liter. Nitrogen recovery from glycine, used to represent a mono-
amino monocarboxy acid, ranged 92-100%. Nitrogen recovery with methionine, used
as a long-change, sulfur-containing amino acid, ranged 96-124%. Tryptophan, as
a heterocyclic acid, exhibited recoveries of 100-160%. Diphenylcarbazone,
insoluble in acid solutions, showed poor recovery of nitrogen, ranging 8.4-120%.
190
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SECTION XIX
WATER QUALITY MANAGEMENT AND PROTECTION
SOURCES AND FATE OF POLLUTION (GROUP O5B)
77:05B-001
EXPERIMENTAL AND SIMULATED TRANSPORT OF PHOSPHORUS THROUGH SANDY SOILS,
Mansell, R.S., Selim, H.M., Kanchanasut, P., Davidson, J.M., and Fiskell, J.G.A,
Florida University, Department of Soil Science, Gainesville, Florida.
Water Resources Research, Vol. 13, No. 1, p 189-194, February 1977. 8 fig,
2 tab, 24 ref.
Descriptors: *Phosphorus, *Soils, *Sands, *Path of pollutants, Laboratory tests,
Model studies, Mathematical models, Phosphates, Phosphorus compounds, Adsorption,
Chemical precipitation, Soil water movement, Leaching, Soil chemistry, Fertilizers,
Pollutants, Water pollution.
Reversible equilibrium adsorption-desorption relationships were inadequate for
describing the transport of orthophosphate through water-saturated and water-un-
saturated cores from surface A sub 1 and subsurface A sub 2 horizons of Olsmar
fine sand. Using a kinetic model with nonlinear reversible adsorption-desorption
improved descriptions of phosphorus transport through these soils. Phosphorus
effluent concentrations were described best by using an irreversible sink for
chemical immobilization or precipitation with a nonlinear reversible kinetic
adsorption-desorption equation.
77:05B-002
LYSIMETER AND FIELD MEASUREMENTS OF CHLORIDE AND BROMIDE LEACHING IN AN UNCULTI-
VATED LOAMY SAND,
Saffigna, P.G., Keeney, D.R., and Tanner, C.B.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Soil Science Society of America Journal, Vol. 41, No. 3, p 478-482, May-June, 1977.
4 fig, 4 tab, 12 ref.
Descriptors: *Leaching, *Halides, *Lysimeters, *Chlorides, *Bromides, *Path of
pollutants. Tracers, Dispersion, Soils, Soil water, Soil water movement, Solvents,
On-site investigations, Drainage, Soil profiles, Soil physics, Soil science.
Field and lysimeter measurements were made of Cl and Br leaching in a Plainfield
loamy sand at Hancock, Wisconsin. Chloride and Br were excellent companion tracers,
moving in a 1:1 ratio through the 500-cm field profile to the water table even
when differences in halide leaching occurred between adjacent sites. Half of the
Cl or Br applied to the lysimeters was leached through the 125-cm lysimeter profile
in 13 or 17 cm of drainage during 22- and 205-day experiments, respectively. Edge
effects in the lysimeter were studied by applying Br near the edge and Cl in the
center. Bromide was detected in the lysimeter drainage before Cl, but overall,
edge effects were small. Lateral movement of Cl and Br in the lysimeter profile
was less than 20 cm, which helps explain why large localized variations in solute
transport can persist to considerable depth in this sandy soil, The differences
in the distribution of halide between adjacent soil profiles within the lysimeter
and field exceeded the average differences between the field and the lysimeter soil
profiles.
77:056-003
EFFECTS OF IRRIGATION MANAGEMENT ON THE QUALITY OF IRRIGATION RETURN FLOW IN ASHLEY
VALLEY, UTAH,
Bliesner, R.D., Hanks, R.J., King, L.G., and Willardson, L.S.
Superior Farming Company, Bakersfield, California.
Soil Science of America Journal, Vol. 41, No. 2, p 424-428, March-April, 1977.
5 fig, 3 tab, 11 ref.
191
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Descriptors: *Leaching, Irrigation effects, *Utah, *Return flow, *Irrigation
water, Salinity, On-site investigations, Sprinkler irrigation, Soil management,
Alfalfa, Electrical conductance, Soil profiles, Lysimeters.
A study was conducted to evaluate reduced leaching fractions under different
field water management conditions. Three qualities of water were applied at
three leaching fractions to areas of an alfalfa (Medicago sativa L.) field
having three depths to the water table. A sprinkler irrigation was used, with
the electrical conductivity of the irrigation water and soil solution extract
at various depths measured for each application. Results indicate that soil
profile salinity is relatively unaffected by leaching fraction for short periods
of time (1 to 2 years), due to high relative concentrations of calcium and sul-
fate in the irrigation water and soil solution. The electrical conductivity of
waters applied averaged 0.98, 2.22 and 2.80 mmhos/cm, respectively, for the
season. Leaching fractions for the low leaching treatment of each water quality
averaged 0.003, with other treatments ranging from 0.082 to 0.343. The total
amount of salt removed in irrigation return flow from such an area varies directly
with drainage water quantity since the concentration is relatively constant.
77:058-004
MODELING NITRATE MOVEMENT AND DISSIPATION IN FERTILIZED SOILS,
Saxton, K.E., Schuman, G.E., and Burwell, R.E.
Agricultural Research Service, Department of Hydraulic Engineering, Columbia,
Missouri.
Soil Science Society of America Journal, Vol. 41, No. 2, p 265^271, March-April,
1977. 5 fig, 1 tab, 27 ref.
Descriptors: *Model studies, *Leaching, *Nitrates, *Iowa, *Path of pollutants,
Water pollution sources, Solutes, Fertilizers, Movement, Soil profiles. Mathe-
matical model, Agricultural watersheds, Soil water movement( Percolation, Soil
moisture, Pollutants, Demonstration watersheds, Crops, Corn (field).
It is important to know the fate of nitrogen (N) fertilizers to ensure crop
production and to avoid pollution, but frequent measurement of soil N is dif-
ficult. Therefore, a digital model was developed to calculate the occurrence,
movement, and dissipation of nitrate-nitrogen (N03-N) within the soil profile
of fertilized agricultural lands. Daily N03-N amounts and distributions within
a 1.8-m soil profile were calculated by representing the major processes in-
fluencing N03-N for the entire year. Daily soil moisture amounts and movement
were predicted by a previously developed soil moisture-evapotranspiration model.
Profiles of N03-N measured periodically on two research watersheds in western
Iowa, one normally fertilized (168 kg/ha per year) and the other excessively
fertilized (448 kg/ha per year) with N, were used for model verification. The
daily calculations for the fertilized cornfields with moderately permeable soils
included N03-N movement, dissipation, and profile leaching. The predicted N03-N
profiles closely represented those measured. Like most prediction methods, this
one was developed to a state of utility, but revisions, improvements, and ad-
ditions always are possible and desirable. Many of the model representations
could be improved by including additional details and refinements. And some
assumptions, like negligible denitrification, could be eliminated if proper
representation were available,
77:058-005
CHEMICAL QUALITY OF EFFLUENTS AND THEIR INFLUENCE ON WATER QUALITY IN A SHALLOW
AQUIFER,
Purtymun, W.D., Buchholz, J.R., and Hakonson, T.E.
Los Alamos Scientific Laboratory, Los Alamos, New Mexico.
Journal of Environmental Quality, Vol. 6, No, 1, p 29-32, January-February, 1977,
2 fig, 4 tab, 5 ref.
Descriptors: *New Mexico, *Water quality, *Alluvial aquifers, *Waste water dis-
posal, Effluents, Water pollution sources, Chemicals, Aquifers, Data collections,
On-site investigations, Evaluation, Storm runoff, Hardness (water), Fluorides,
Calcium, Carbonates, Sodium, Nitrates, Chlorides, Bicarbonates,
192
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The chemical quality of liquid effluent released from an industrial waste treat-
ment plant at the Los Alamos Scientific Laboratory controls the quality of water
in a shallow aquifer in the alluvium of Mortandad Canyon. The dilution of the
effluent with surface flow in the canyon reduces the concentrations of the chemicals
as they move down gradient into the aquifer. Mass estimates of residual chemicals
in solution in the aquifer average 1-6% of the total chemicals released to the
canyon from 1963-1974. The average annual concentration of sodium, nitrate, chloride,
and total dissolved solids in the aquifer through a 12-year period was directly
correlated with annual average concentrations in the effluent. This relationship
provides a means of predicting the impact of the chemical effluents on the quality
of water in the aquifer. Chemical concentrations in solution in the aquifer have
increased over prerelease levels; however, there has not been a steady accumulation
of these materials in the water with time. The rapid loss of water and its as-
sociated chemicals from the aquifer prevents chemical accumulation and indicates
that cessation of effluent release to the canyon would rapidly improve the quality
of water in the aquifer.
77:056-006
PERSISTENCE OF PROPANIL, DCA, AND TCAB IN SOIL AND WATER UNDER FLOODED RICE CULTURE,
Deuel, I.E., Jr., Brown, K.W., Turner, F.C., Westfall, D.G., and Price, J,D.
Texas Agricultural Experiment Station, College Station, Texas.
Journal of Environmental Quality, Vol. 6, No. 2, p 127-132, April-June, 1977. 6
fig, 3 tab, 14 ref.
Descriptors: *Pesticides, *Herbicides, *Irrigation, *Rice, Pollutants, Agricultural
chemicals, Analytical techniques, Pesticide residues, Sprays, Leaching, Water pol-
lution, Soil contamination, Water pollution sources, Pollutant identification,
Water quality. Agronomy, Soil analysis, Water analysis.
Field experiments were conducted to determine the residue levels of propanil (3',
4' -dipropionanilide, DCA (3, 4-dichloroaniline), and TCAB (3, 3', 4, 4'-
tetrachloroazobenzene) in the flood water and Beaumont clay soil under normal
rice (Oryza sative L.) cultivation. Propanil applied as a foliar spray at 3.4
and 6.8 kg/ha 24 hours before flooding was dissipated from the flood water within
24 hours following the flood. The amount of propanil dissipated corresponded to
the DCA concentration in the flood water at 24 hours, indicative of biological
quantities. Neither propanil nor its metabilities were detected in soil samples
collected at 2.5-5.0 cm and 17.5-20.0 cm below the surface 24 hours following
the application of the flood water.
77:05B-007
EFFECT OF TEMPERATURE AND HYDROXY ALUMINUM INTERLAYERS ON THE ADSORPTION OF
TRACE RADIOACTIVE CESIUM BY SEDIMENTS NEAR WATERS-COOLED NUCLEAR REACTORS,
Elprince, A.M., Rich, C.I., and Martens, D,C,
Virginia Polytechnic Institute and State University, Department of Soils and Water,
Blacksburg, Virginia.
Water Resources Research, Vol. 13, No. 2, p 375-380, April 1977. 3 fig, 1 tab,
38 ref.
Descriptors: *Cesium, *South Carolina, *Radioactive wastes, *Nuclear reactors,
Thermal pollutions, *Radioisotopes, Nuclear wastes, Water pollution sources,.
Radiochemical analysis, Water quality, Water pollution, Adsorption, Chemical
properties, Expansive clays, Heat pollution, Water temperature, Physical pro-
perties, Sediments.
The adsorption of Csl37 by sediments from the Savannah River Plant follows a
theoretically expected linear relationship between In Kd and 1/T where Kd and T
are the equilibrium distribution coefficient (Cs adsorbed, meg/g/Cs(+) in solution,
meq/ml) and the temperature in kelvins, respectively. The slope of the plots
decreases after removal of hydroxy Al interlayers with citrate pretreatment,
Hydroxy Al interlayers thus make Cs ( + ) adsorption more temperature dependent. The
thermal effect of hydroxy Al interlayers becomes more significant in sediments con-
taining a swelling 2:1-2; 2 intergrade clay mineral. The phenomenon was explained
by considering hydroxy Al interlayers as a source of hydronium_ions H30(-} which
compete with Cs(+} for exchange positions in wedge zones. An increase in^tempera-
ture favors an increase in H30(-) ions, which in turn favors less adsorption of
Cs(+). Aside from the thermal effect, the positively charged hydroxy aluminum
polymeric groups drastically decrease the cation exchange capacity and, conse-
quently, the adsorption of cesium.
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77:058-008
SIMULATION OF TWO-DIMENSIONAL CONTAMINANT TRANSPORT WITH ISOPARAMETRIC HERMITIAN
FINITE ELEMENTS,
van Genuchten, M.T., Pinder, G.P., and Frind, E.G.
Princeton University, Department of Civil Engineering, Princeton, New Jersey-
Water Resources Research, Vol. 13, No. 2, p 451-458, April 1977. 10 fig,
11 ref.
Descriptors: *Pollutants, *Soil contamination, *Model studies, *Mathematical
models, Mathematical studies, Mathematics, Finite element analysis. Path of
pollutants, Dispersion, Infiltration, Analytical techniques, Data processing,
Groundwater movement.
A deformed isoparametric Hermitian element can be used in the simulation of two-
dimensional contaminant transport. The degree of freedom arising from the cross
derivative may be eliminated in the Galerkin-type finite element formulation,
reducing the computational effort per node. Two example problems demonstrated
that the Hermitian element gives results which are comparable to those obtained
with the zero-order continuous cubic element but requires 25-40% fewer degrees
of freedom, depending on the geometrical description of the problem.
77:058-009
HERBICIDES FROM CROPPED WATERSHEDS IN STREAM AND ESTUARINE SEDIMENTS IN HAWAII,
Green, R.E., Goswami, K.P., Mukhtar, M., and Young, H.Y.
Hawaii University, Department of Agronomy and Soil Science, Honolulu, Hawaii.
Journal of Environmental Quality, Vol. 6, No. 2, p 145-154, April-June, 1977.
1 fig, 7 tab, 34 ref.
Descriptors: *Pesticides, *Herbicides, *Agricultural chemicals, *Pollutants,
*Water quality, *Hawaii, Water pollution, Soil contamination, Agronomy, Soil
analysis, Sugarcane, Sediments, Degradation (decomposition), Runoff, Phytoplankton,
Marine biology, Analytical techniques, Path of pollutants.
Analysis of sediments and soils associated with two estuaries on Oahu was con-
ducted to determine if herbicides used in plantation crops reach coastal waters.
Analytical procedures were developed for simultaneous extraction of atrazine,
ametryn, diuron, and DCA. Field soil and runoff samples from two small monitored
watersheds provided additional information on the dissipation of diuron in sugar-
cane and pineapple fields, and on diuron removal in runoff waters. Atrazine and
ametryn dissipated rapidly in field soils, and neither was found normally in
stream and estuarine sediments. Diuron, on the other hand, was sufficiently
persistent in soils and sediments to be found in nearly all sediment samples
obtained at six month intervals at several sites for each estuary and its
associated streams. Diuron in sediments was generally less than 500 ppb (oven-
dry basis), but occasionally much higher concentrations were encountered at
sites which were subject to localized contamination from spray equipment loading
areas. Diuron appears to be transported in runoff waters principally in the
solution phase rather than adsorbed on suspended solids. Estuarine waters (West
Loch) contained 0.1 to 1 ppb diuron, while concentrations i runoff waters were
several times higher. It is not known if the chronic low levels adversely affect
the ecological balance of the estuary-
77:058-010
NITRATE-N PERCOLATION THROUGH IRRIGATED SANDY SOIL AS AFFECTED BY WATER
MANAGEMENT,
Smika, D.E., Heermann, D.F., Duke, H.R., and Bathchelder, A.R.
Agricultural Research Service, Akron, Colorado.
Agronomy Journal, Vol. 69,- No. 4, p 623-626, July-August, 1977. 3 fig, 3 tab,
9 ref.
Descriptors: *Water management (applied), *Percolation, *Fertilizers, *Water
pollution, *Nitrates, Nitrogen, Groundwater, Soil types, Sands, Irrigation
effects, Irrigation systems, Sprinkler irrigation.
A study was conducted to determine the magnitude and difference in N03N losses
from two widely different but current farmer-used fertilizer management
practices with scheduled irrigation systems on sandy soils. The experiments were
194
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conducted during three consecutive corn growing seasons on three irrigation
systems in Colorado. Nitrate-N percolation losses were measured in water
samples collected at 150 centimeters below the soil surface in vacuum extractors.
The actual amount of N03N that will move through the soil is proportional to
the concentration of N03N in the soil and the amount of water that moves through
the soil. The movement of nitrogen fertilizer below the major root zone of corn
grown on loamy fine sand soils can be kept very small with proper water and ferti-
lizer management, thereby minimizing the N03N pollution potential of the ground-
water.
77:05B-011
QUALITY OF IRRIGATION RETURN FLOW FROM FLOODED RICE PADDIES,
Brown, K.W., Deuel, L.E., Turner, F.C., and Price, J.D.
Texas A & M University, Department of Soil and Crop Sciences, College Station,
Texas.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 153-166, May 16-19, 1977.
16 fig, 18 tab.
Descriptors: Irrigation, Return flow, Rice, Pesticides, Nutrients, Nitrates,
Phosphates, Potassium, Fertilizers, Irrigation water.
A three year field aad laboratory study was conducted to determine the quantity
and quality of irrigation return flow from flooded rice culture. Both inter-
mittent and continuous flow irrigation techniques were evaluated. Selected
pesticides and nutrients were applied at recommended and excessive rates. The
concentrations of nitrate, phosphate and potassium in the return flow were all
within levels acceptable for drinking water. Only small amounts of the ferti-
lizer applied to the soil before flood or in the floodwater were lost in the
irrigation return flow. The large amounts of rainfall received each year diluted
the salts in the flood water so that the salt load of irrigation return flow did
not differ greatly from that of the irrigation water. Increases in the electrical
conductivity of the floodwater resulted from the release of certain ions from the
soil after fertilizer applications. These increases lasted for periods of 5-10
days.
77:05B-012
EVALUATION OF SURFACE IRRIGATION RETURN FLOWS IN THE CENTRAL VALLEY OF CALIFORNIA,
Tanji, K.K., Biggar, J.W., Miller, R.J., Pruitt, W.O., and Horner, G.L.
California University, Department of Land, Air and Water Resources, Davis,
California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 167-173, May 16-19, 1977.
9 fig, 2 tab, 7 ref.
Descriptors: Variability, Return flow. Water quality, Water quality control.
The variability in the quantity and quality of surface return flows from two
typical irrigation districts is reported for the 1975 and 1976 irrigation seasons.
Factors contributing to such variations are noted. Emphasis is placed upon the
concentration and mass emission of TDS and SS. The implications of these findings
are discussed relative to PI 92-500 and best management practices.
77:05B-013
MODELING SALT TRANSPORT IN THE IRRIGATED SOILS OF GRAND VALLEY,
Ayars, J.E., McWhorter, D.B., and Skogerboe, G.V.
Maryland University, Department of Agricultural Engineering, College Park,
Maryland.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 369-374, May 16-19, 1977.
6 fig, 1 tab, 6 ref, 2 equ.
Descriptors: Model studies, Simulation analysis, Colorado, Colorado river,
Salinity, Saline soils, Saline water, Leachate, Return flow.
This study was undertaken to evaluate the effects of the volume of leachate leaving
the soil profile on the quality of the leachate. A numerical salt transport model
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was selected for use in the study. Field data to calibrate the model were collected
on 63 research plots located in the Grand Valley. The model was tested and cali-
brated with the field data and then used in a series of hypothetical_simulations
designed to provide the required information. The modeling results indicate that
the salt concentration of the leachate is independent of the volume of leachate.
The six-year simulation showed that the concentration of salt below the root zone
was relatively constant. Therefore, the salt loading due to subsurface irrigation
return flows can be calculated from a water budget analysis, with salt load
reductions being directly proportional to the reduced volume of subsurface return
flow.
77:058-014
UPTAKE AND LOSSES OF 15N APPLIED TO ANNUAL GRASS AND CLOVER IN LYSIMETERS,
Jones, M.B., Delwiche, C.C., and Williams, W.A.
California University, Department of Agronomy and Range Science, Davis, California.
Agronomy Journal, Vol. 69, No. 6, p 1019-1023, November-December, 1977. 2 fig, 3
tab, 10 ref.
Descriptors: Nitrogen, Lysimeters, Fertilizers, Fertilization, Nutrients, Leaching,
California, Denitrification.
The California annual grasslands comprise about one-third of th,e state, and they
play a large role in the hydrology of most watersheds in central and northern
California. Apparent recovery of applied N has been low, and a large percentage
has been unaccounted for in N balance studies. The present experiment was done
with 15N to determine the fate of applied N, especially that leached and that
volatilized (by difference). Conclusions: There was modest leaching loss but
essentially no gaseous loss from moderate rates of N applied to grass in February;
recovery of fertilizer by clover was poor; and a single large application (500 kg
N/ha) resulted in a substantial leaching and gaseous losses under both grass and
clover.
77:058-015
DEICING SALT MOVEMENT AND ITS EFFECTS ON SOIL PARAMETERS AND VEGETATION,
Buzio, C.A., Burt, G.W., and Foss, J.E.
Maryland University, Department of Agronomy, College Park, Maryland 20742.
Agronomy Journal, Vol. 69, No. 6, p 1030-1032, November-December, 1977. 3 fig,
1 tab, 13 ref.
Descriptors: Salts, Soils, Soil investigations. Soil properties, Chlorides,
Salinity, Saline soils.
Salt damage to the environment occurs in restricted areas in humid regions as a
result of factors such as industrial waste, sea water, and deicing salt. A
study was conducted, therefore, to determine the distribution of salt leached
from a deicing salt pile, and its effects on soil parameters (pH, Mg, P, and K)
and plant successional changes in a hardwood forest area. Lateral movement and
leaching of chloride was studied as it occurred in an adjacent slope by
sampling the soil to a depth of 76 cm at 17 sites. The soil samples collected
from the field were then analyzed for salt content by using the conductivity
bridge. Lateral movement (of chloride) was extensive with subsequent leaching
to a depth greater than 76 cm. Of the measured soil parameters, only K was
found to be correlated with NaCl concentration. Within three years of the
establishment of the salt stockpile, all the trees in the sampled area were dead.
Out of 29 plant species found to have invaded the sites with less than 5,000 ppm
of NaCl, only 10 were found in sites with concentrations greater than 15,000 ppm.
Recommendations to be considered when establishing a deicing salt pile are
presented.
77:05B-016
SOLUTE TRAVEL TIMES TO WELLS,
Kirkham, D., and Affleck, S.B.
Iowa State University, Department of Agronomy, Ames, Iowa.
Ground Water, Vol. 15, No. 3, p 231-242, May-June, 1977. 7 fig, 15 ref.
196
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Descriptors: *Groundwater, *Solutes, *Groundwater movement, *Traveltime, *Model
studies, Mathematical models, Aqueous solutions, Nitrates, Wells, Water wells,
Water pollution, Water pollution sources, Hydraulic conductivity.
Theoretical travel times were given for a solute to reach a well from an injection
point for wells that fully penetrate confined aquifers of constant thickness and
mainly constant conductivity and porosity. Solute is assumed to move along
streamlines with the water in piston flow under steady flow conditions. Three
cases were considered. (1) For a "standard" well of external radius of influence
r sub e and well radius r sub w, the travel time varies approximately directly
as the square of the distance r of the injection point from the well, as the
ratio f/K of porosity to conductivity, and as In r sub e/r sub w. (2) For a well
in which the flow region is divided by radius r sub c into two regions, with the
region next to the well clogged and of very low conductivity, K sub I, the travel
time varies approximately directly as r squared, as f/K sub I, and as 1 n r sub
c/r sub w. (3) For a well being fed from a line drive (river) at a distance d
from the well, the travel time from a point on the line drive to the well varies
as the distance d squared, as f/K, as 1 n 2nd/r sub w, and as a function of the
position of the point along the line drive. In each case, the travel time is in-
versely proportional to h sub e - h sub w, where h sub e is the head at the
radius of influence r sub e (or at the line drive) and h sub w is the head
at the well. In the three cases, doubling the pumping rate halves the travel
time. Travel times can affect the extent of chemical changes of the solute
(contaminant) during its flow to the well.
77:058-017
NITRATE AND CHLORIDE IN GROUND WATER UNDER IRRIGATED AGRICULTURE IN CENTRAL
WISCONSIN,
Saffigna, P.G., and Keeney, D.R.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Ground Water, Vol. 15, No. 2, p 170-177, March-April, 1977. 3 fig, 4 tab, 18 ref.
Descriptors: *Nitrates, *Chlorides, *Groundwater, *Wisconsin, Agriculture,
Irrigation, Return flow, Leachate, Fertilization, Potatoes, Beans, On-site data
collections, Groundwater movement, Sampling, Water quality. Land management.
Results of this study indicated that the nitrate and chloride concentrations in
the groundwater of the central Wisconsin sand plains are signficantly above
background, and that the main source is the irrigated agriculture in the region.
The study was conducted at three levels of intensity: a small field during one
growing season, a University Experimental Farm over several years, and many
local farms during part of a growing season. Differences in concentrations of
nitrate-N and chloride in the surface of the groundwater underlying the moderately
fertilized potato field closely reflected the fertilizer and irrigation manage-
ment on different parts of the field during that season. This detailed study
of one field showed that solute transit times through the 16 ft. (5 m) of un-
saturated zone to the surface of the groundwater are less than a year.
Differences in concentration of nitrate-N and chloride between irrigation wells
on the Experimental Farm closely reflected the irrigation and fertilizer
practices on surrounding fields. On a large scale, the nitrate-N and chloride
concentrations in area farmer irrigation wells were as different between wells
on the same farm as among the various farms.
77:05B-018
GROUNDWATER TURBIDITY RESULTING FROM ARTIFICIAL RECHARGE,
Nightingale, H.I., and Bianchi, W.C.
Agricultural Research Service, Fresno, California.
Ground Water, Vol. 15, No. 2, p 146-152, March-April, 1977. 8 fig, 1 tab, 21 ref.
Descriptors: *Groundwater, *Turbidity, California, Groundwater recharge, Arti-
ficial recharge, Salinity, Wells, Groundwater movement, Hydrology, Aquifers,
Aquifer testing, Laboratory tests, On-site investigations.
Turbid groundwater is rarely observed in domestic or public supply aquifers. At
the Leaky Acres Recharge Facility at Fresno, California, water of low salinity
(less than 50 micromhos/cm) and turbidity (less than 5 FTU, Formazin turbidity
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units) is recharged in the spreading basins. Six months after the start of the
third (1973) recharge period, the groundwater salinity was decreased to about 100
micromhos/cm from the initial mean of 147 micromhos/cm, and the groundwater
became visibly turbid (more than 5 FTU). Two months later, some peripheral
domestic wells also began to become turbid. After two more recharge periods
(1974 and 1975), turbidity at 10 observation wells beneath Leaky Acres averaged
18 FTU, and salinity averaged 74 micromhos/cm. By this time, groundwater
turbidity in peripheral wells near Leaky Acres had decreased to less than 0.5
FTU. This turbidity was raced to poorly crystallized and extremely fine colloids,
which have leached from the surface soils because of the low salinity of the
recharge water. Laboratory and field studies showed that gypsum application
will reverse the phenomena, but such treatment is uneconomical. This phenomenon
is a transient one, and now turbidity outside the recharge area is insignificant
from a water quality viewpoint. However, the magnitude of the mass of material
in transit through the profile if stabilized through flocculation or sieving
in soil pore space, could greatly change the water transmission and so recharge
project performance. However, this effect has not yet been noted at Leaky Acres.
77:056-019
AN INTEGRATED APPROACH TO DELINEATING CONTAMINATED GROUND WATER,
Berk, W.J., and Yare, B.S.
Berk and Ciaramella, Cranbury, New Jersey.
Ground Water, Vol. 15, No. 2, p 138-145, March-April, 1977. 5 fig, 3 tab, 6 ref.
Descriptors: *Groundwater, *Water pollution sources, *Atlantic coastal plain,
*Groundwater movement, Observation wells, Groundwater recharge, Water pollution,
Hydrogeology, Sodium chloride, Aquifers, Hydrology.
Disposal of industrial process water into an unlined lagoon in permeable Atlantic
Coastal Plain sediments resulted in a groundwater contamination problem caused
by infiltration of the process water into a major unconfined aquifer which un-
derlies the lagoon at shallow depth. Most of the area water supply wells termi-
nate in this formation. Before this disposal method was discontinued, traces of
the process water appeared in nearby wells. Because of the relatively large area
and depths involved, as indicated by preliminary data, delineation of the dis-
tribution of contaminant within the aquifer through a systematic well drilling
program posed a significant economic problem. To keep costs within a reasonable
range, a resistivity survey program was implemented to obtain information on the
gross distribution of the contaminant and to provide data for the selective
location of monitor wells. Eight wells were constructed to obtain samples of
the groundwater in order to measure contaminant concentrations and to verify the
interpretations of areal contaminant distribution inferred from the resistivity
data. The groundwater sampling procedure developed during this investigation
was described. The combination of the resistivity survey with the groundwater
sampling procedure developed during this investigation proved to be a valuable
and reliable technique for delineating in three dimensions a contaminant body
within an aquifer in unconsolidated sediments. Utilization of the resistivity
survey data to selectively locate the monitor wells and to define the lateral
extent of the contamination increased the efficiency of the investigation and
significantly reduced'the cost of the program.
77:058-020
WATER QUALITY VARIATIONS FOR PUMPING WELLS,
Schmidt, K.D.
Groundwater Quality Consultant, Fresno, California.
Ground Water, Vol. 15, No. 2, p 130-137, March-April, 1977. 7 fig, 9 ref.
Descriptors: *Groundwater, *Water quality, *Monitoring, California, *Water
wells, Water pollution. Nitrates, Shallow wells, Alluvial aquifers, Fluctuations,
Variability, Sampling, Water sampling, Seasonal, Water supply, Pumping.
Past groundwater quality monitoring programs have often involved sampling of
low-capacity wells near point or line sources of recharge or pollution. However,
large-capacity wells produce much of the groundwater pumped for municipal, indus-
trial, and agricultural uses. Short-term, seasonal, and long-term fluctuations
in quality are common for water pumped from many large-capacity wells. In many
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cases, there is a considerable difference between in-sitn "nr x 4-
and the quality of water sampled at the well discharge Shorttf
for several municipal wells in the San Joaguin Valley CaUr'ornia i
nitrate concentrations decreased exponentially with pumping time VaSabifff- *
in pump operation creates substantial short-term chanoes in woT?" Variability
Short-term changes are most evident for infrecently pumpeS sJalT" ?f ^
point or line sources of recharge or pollution q^Lon*? * shallow wells near
been documented for water from wel?s in areas of diSuse sourcL^of" 'n *^ ^
such as agricultural return flow and septic tanks These ohanaes fr^fl "'
raarily to significant changes in depth lo water and vertL2 hydraulic heal""
gradient. Once the short-term and seasonal trends are established the ootirn.i
sampling approach can be determined in order to establish long-term trends
77:05B-021
QUANTIFYING THE NATURAL FLUSHOUT OF ALLUVIAL AQUIFERS,
Fryberger, J.S., and Bellis, W.H.
Engineering Enterprises, Inc., Norman, Oklahoma.
Ground Water, Vol. 15, No. 1, p 58-65, January-February, 1977. 6 fig, 7 ref.
Descriptors: *Alluvial aquifers, *Groundwater, *Water pollution, *Model studies,
Mathematical models, Water quality. Salinity, Salts, Precipitation (atmospheric),
Flow, Groundwater movement, Base flow, Alluvium, Evapotranspiration, Evaporation,
Pollutants, Path of pollutants, Forecasting, Pollution.
A plume of contaminated water may extend downstream for several miles in an
alluvial aquifer. Hydrologic forces acting on the aquifer generally tend to
dilute the contaminant downstream from the source. After the pollution has been
stopped, how rapidly will these hydrologic forces flush out the contaminant. The
answer to this question may be calculated by using the mass-balance equation herein
developed. This described mass-balance mathematical model incorporates all the
hydrologic forces acting on the alluvial aquifer that affect the concentration of
the contaminant. Methods were presented to define and quantify each of the hydro-
logic forces. These forces include: (1) present quantity and quality (with respect
to contaminant) of water in the alluvium and the change in the quality downstream,
(2) quantity and quality of groundwater inflow, (3) quantity and quality of flood
inflow, (4) quantity and quality of base flow, (5) quantity of recharge from preci-
pitation, and (6) quantity of loss from evapotranspiration. The equation was first
balanced to agree with past conditions and observed field data, and it was then
used to predict future quality changes after the pollution is stopped. The
method is applicable primarily to situations in which the pollution has been
taking place over a long period of time and the water quality in the alluvium
has reached equilibrium at any given point. Modifications may be possible to
permit use of the general approach to short-term of slug-type pollution events.
77:058-022
PROBLEMS OF HEAT STORAGE IN AQUIFERS,
Werner, D., Kley, W.
Eidgenoessische Technische, Zurich (Switzerland).
Journal of Hydrology, Vol. 34, No. 1/2, p 35-43, July 1977. 3 fig, 7 ref.
Descriptors: *Thermal pollution, *Storage, *Heated water, *Aquifers, On-site
investigations, Model studies, Mathematical models, Underground storage, Heat
transfer, Diffusion, Convection, Temperature, Groundwater, Powerplants, Nuclear
powerplants, Wells, Injection wells.
A hydrothermic field experiment near Krefeld (Federal Republic of Germany) was
used to study the propagation of heat in groundwater. For two months, water at
a temperature of 45 C was fed through a well pipe to the water-bearing strata,
the distribution of temperature in the surrounding space was measured, and its
variation with time was observed. A theoretical model was developed to simulate
the field experiment. The model consisted of a time-spaced differential method
with the help of which good conformity between theory and experiment was
obtained. The aim of the study was to ascertain the physical bases for the
storage of heat in groundwater. The technoeconomic and environmental problem was_
posed because of the enormous quantities of cooling water necessary in the operation
of atomic power stations. A functional theoretical model can help to decide how
far the idea of storing heat in an aquifer is technically feasible.
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77:05B-023
INTERFACIAL REACTIONS AND THE FATE OF HEAVY METALS IN SOIL-WATER SYSTEMS,
Huang, C.P-, Elliott, H.A., and Ashmead, R.M.
Delaware University, Newark, Delaware.
Journal Water Pollution Control Federation, Vol. 49, No. 5, May 1977, p 745-
756. 8 fig, 1 tab, 32 ref.
Descriptors: *Water pollution sources, *Heavy metals, Interfaces, Earth-water
interfaces, Chemistry, Adsorption, Chemical precipitation, Soil chemistry,
Solubility.
The processes and factors that govern the fate of heavy metals in the soil-
water system are identified as dissolution-precipitation and adsorption. The
congruent and incongruent solubility of oxides, hydroxides, sulfates, sulfides,
and carbonates of heavy metals contributes to the chemical constituents of
soil-water. The process is influenced by pH, redox potential, the amount of
carbonate and sulfur present and the presence of organic substances. The
formation of metal-chelates or metal complexes can render metal solids more
soluble. Microorganisms, whose metabolic activities tend to modify the redox
potential and contribute organic acids can influence the solubility of metal
solids. Interfacial association between heavy metals and soil minerals is
considered the most important process in regulating the concentration of heavy
metals in the soil-water environment. Copper and zinc are more removable than
lead and cadmium. When the solid surfaces are very positively charged, posi-
tive lead and cadmium ions are expelled away from the interface and result in
an excess of metal ions in the bulk phase of the soil-water system.
77:058-024
RELATION OF CLIMATE TO LEACHING OF SOLUTES AND POLLUTANTS THROUGH SOILS,
Tanner, C.B.
Wisconsin University, Department of Soil Science, Madison, Wisconsin.
Final Report to NOAA, Environmental Data Service, May 20, 1977. 39 p, 9 fig,- 9
tab.
Descriptors: *Soil water movement, *Pollutants, *Climates, *Nitrates, *Leaching,
*Path of pollutants, Soil physics, Groundwater, Evapotranspiration, Irrigation,
Water pollution sources, Soil contamination.
The original study had two objectives: (1) To test whether a simple soil
physics model of nitrate leaching could be combined with analysis of weather
records to model nitrate movement to the water table. This embraces both the
concentration distributions in the soil and the total flux. Leaching is greatest
when heavily fertilized and irrigated crops are grown on sandy soils. (2) The
second objective was to determine whether the leaching information could be
used to improve irrigation and fertilizer management to minimize leaching and
improve management efficiency of crops where nitrogen and irrigation are used
intensively.
77:05B-025
COMPLETION REPORT ON CONTRIBUTION OF FERTILIZERS TO WATER POLLUTION,
Douglas, L.A., and Bourodimos, E.L.
Rutgers, Department of Soils and Crops, New Brunswick, New Jersey.
Completion Report, Water Resources Research Institute, Rutgers University,
New Brunswick, New Jersey, July 1977. 8 p, 3 ref.
Descriptors: *Nitrates, *Nitrites, *Ammonia, *Phosphates, *Leaching, *Fertilizers,
Land use, Denitrification, Water pollution sources. Path of pollutants.
Field studies were undertaken to determine the magnitude of leaching of fertilizer
N03, NH4, and P04. The effect of N-serve on these reactions was observed, and
little effect on leaching was found because most leaching takes place during the
fall and winter when precipitation exceeds evapotranspiration. No leaching takes
place during the fall and winter when precipitation exceeds evapotranspiration.
No leaching of NH4 and P04 was observed. The common fertilizer efficiency mea-
sure of N in crop/N applied in fertilizer may be used as an indication of the
amount of fertilizer N that will be leached. Studies of nutrients in streams
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were undertaken to relate land use to N03, NH4 and P04 concentrations in surface
waters. Sewage treatment plants and "illegal drains" were found to be major
sources of all three ions. In order of decreasing contribution of N03- urban
land contributes more than cropland which contributes more than woodlands. Urban
lands, croplands and woodlands contribute equal amounts of NH4 and P04 to streams
The "background level" of P04 in central New Jersey streams is many times higher
than the 0.01 ppm level often advocated. Although very high concentrations of
N03 were found in the soil solution in the subsoil the concentration of N03 found
in streams was rather low. Denitrification must be an active process in subsoils,
and probably in the groundwater. Groundwater studies were also undertaken, but
they were inconclusive.
77:058-026
SIMULATION OF NUTRIENT LOADINGS IN SURFACE RUNOFF WITH THE NFS MODEL,
Donigian, A.S., Jr., and Crawford, N.H.
Hydrocomp, Incorporated, Palo Alto, California.
EPA Report No. 600/3-77-065, June 1977. 110 p, 30 fig, 8 tab, 24 ref, 3 append.
Descriptors: *0rganic loadings, *Storm water, *Mathematical models, *Nutrients,
*Urban runoff, Computer models, Phosphorus, Nitrogen, Iron, Suspended solids,
Monitoring, Waste water treatment.
The Nonpoint Source Pollutant Loading (NFS) Model was evaluated for simulation of
nutrient loading in surface runoff with one urban and two small agricultural
watersheds. The NFS model was used to simulate total solids, total Kjeldahl
nitrogen, total phosphorus, and iron for storm runoff over an 18-month period.
Phosphorus, total nitrogen, and iron values predicted by the model compared
favorably with observed values. Other parameters such as ammonia nitrogen,
nitrate nitrogen^, and phosphate phosphorus, which are transported in solution
rather than in the sediment fraction of surface runoff, were not predicted as
accurately. The NFS model is suggested as an adequate means of simulating
nutrient loadings on the basis of sediment loss. Application of the model may
be limited .if subsurface flow in the area being considered is a major portion of
total runoff.
77:058-027
ENVIRONMENTAL MODEL OF KISSIMMEE RIVER BASIN,
Bedient, P.B., Huber, W.C., and Heaney, J.P.
Rice University, Department of Environmental Science and Engineering, Houston,
Texas.
Journal of the Water Resources Planning and Management Division, American Society
of Civil Engineers, Vol. 103, No. WR2, Proceedings Paper 13326, p 241-256,
November 1977. 10 fig, 2 tab, 13 ref, 2 append.
Descriptors: *Runoff, *Drainage, *Florida, *Model studies, *Path of pollutants,
Mathematical models, Wa£er quality. Flood control, Land use, Water pollution,
Pollutants, Phosphorus, Rivers, Lakes, Watersheds (basins), Hydrographs, Hydrology.
A hydrologic land-use model was developed and applied to the Kissimmee River
Basin, Florida. Surface runoff quantity and quality were estimated for changing
land-use and drainage patterns in order to explain hydrologic and water quality
response along the river. The hydrologic model (HLAND) was based on a daily
water balance for each soil land-use type in the watershed. Predicted runoff was
routed down the river and compared to measured outflow hydrographs. Phosphorus
loading rates were calculated using measured concentrations of total P and pre- _
dieted runoff volumes. Observed concentrations and loading rates from tributaries
along the river correlated well with the drainage density index, defined as the
length of drainage network per unit area of watershed. Results indicated that
greatest potential for control of runoff quantity and quality exists in on-site
storage in marsh, pond, and lake areas.
77:05B-028
INTERACTIVE EFFECT OF SALINITY AND PHOSPHORUS ON SESAME,
Cerda, A., Bingham, F.T., and Hoffmap, G.J. . , ,
California University, Department of Soil and Environmental Science, Riverside
California 92521.
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Soil Science Society of America Journal, Vol. 41, No. 5, p 915-918, September-
October, 1977. 3 fig, 3 tab, 12 ref.
Descriptors: Salinity, Phosphorus, Crop response, Salts, Salt tolerance.
A solution culture experiment was conducted with a short-season sesame to observe
interactive effects of osmotic potential, and P concentration on water relations,
mineral nutrition, and yield characteristics. Salinity reduced yields linearly
with a 50% decrease in pod yield at an osmotic potential of approximately -2.7
bars. Increasing P concentrations increased yields only at low salinity levels;
at higher salinity levels, yields decreased progressively as P increased. Salt
tolerance was reduced by the higher P additions.
77:05B-029
SIMULATION OF NUTRIENT LOSSES FROM CROPLAND,
Tubbs, L.J., and Haith, D.A.
Cornell University, Department of Agricultural Engineering, Riley-Robb Hall,
Ithaca, New York 14853.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Chicago, Illinois, p 1-34. 17 fig, 14 tab,
34 ref, 38 equ.
Descriptors: Model studies. Nitrogen, Phosphorus, Runoff, Hydrogen, Nutrients,
Infiltration, Simulation analysis.
A mathematical model has been developed to predict losses of nitrogen and phos-
phorus in cropland runoff and percolation water. The model is based on daily
hydrologic and monthly soil nutrient balances. The model does not require cali-
bration and has been validated using data from monitored field plots. Reasonable
predictions of annual losses are obtained for dissolved inorganic nitrogen in
runoff and percolation and dissolved inorganic phosphorus in runoff. Seasonal
variations are well predicted for nitrogen but not for phosphorus.
77:058-030
TILLAGE SYSTEM EFFECTS ON RUNOFF WATER QUALITY: SEDIMENTS AND NUTRIENTS,
Johnson, H.P., Baker, J.L., Shrader, W.D., and Laflen, J.M.
Iowa State University, Department of Agricultural Engineering, Ames, Iowa 50011.
Presented at the 1977 Winter Meeting, American Society of Agricultural Engineers,
December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-15. 2 fig, 3
tab, 9 ref.
Descriptors: Corn, Nitrogen, Erosion, Soil erosion, Phosphorus, Soil conservation,
Water quality. Sediments, Nutrients.
Three tillage systems were utilized for growing corn on six paired small watersheds.
The tillage systems retained a range of residue cover on the soil varying from
about three to forty-five percent. Most of the nitrogen losses were associated
with erosion. Soluble phosphorus losses were greatest with conservation tillage.
Surface residue reduced markedly the soil losses.
77:058-031
A HAZARD OF SUBDIVIDING FARMLAND,
Whitlock, W.W., Jr.
Harford County Health Department, BelAir, Maryland.
Ground Water, Vol. 15, No. 6, p 416-419, November-December, 1977. 2 fig, 4 ref.
Descriptors: *Groundwater, *Water quality, *Nitrates, *Maryland, Wells, Water
wells. Farms, Farm wastes, Land use, Urbanization, Suburban areas, Nitrogen,
Sampling, On-site data collections, Water chemistry. Hazards, Public health,
Pollutants, Water pollution.
Changing land-use patterns are occurring in all areas of the United States,
especially those surrounding urban centers. Previously farmed land is being
converted to residential subdivisions of 1/4 to 1/2 acre lots with on-site
water supply and sewage disposal systems (well and septic). This in itself
can also cause hazards resulting from the original uses of the land that have
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not been anticipated. This paper was concerned with the high nitrate nitrogen
levels in groundwater resulting from long-term farming. Natural chemicals and
biological activity will break down manure to persistent nitrate that is then
leached into the water table. Subsequent subdivision of the land, well installa-
tion, and consumption of the contaminated groundwater constitute a problem that
has been recognized medically since 1945, but not by the drilling industry or
environmental health personnel. Regulations of the Maryland State Department of
Health and Mental Hygience provide for a required series of bacteriological and
chemical samples prior to the water supply being put into service. To date,
the tests usually are conducted after occupancy, if at all. In Harford County,
Maryland, at least 4 subdivisions have been shown to have areas of excessive ni-
trate nitrogen (up to -60 ppm) showing the need for stringent enforcement of
existing regulations.
77:05B-032
RETENTION AND LEACHING OF NUTRIENTS IN A LIMED ULTISOL UNDER CROPPING,
Juo, A.S.R., and Ballaux, J.C.
International Institute of Tropical Agriculture PMB 5320, Ibadan, Nigeria.
Soil Science Society of America Journal, Vol. 41, No. 4, p 757-761, July-
August, 1977. 3 fig, 6 tab, 15 ref.
Descriptors: Maize, Leaching, Nutrients, Greenhouses, Soils, Soil investigations,
Crop response, Crop production.
The response of maize to liming and the retention and leaching of Ca and other
nutrient ions were studied in the greenhouse using an acid Ultisol from southern
Nigeria. The soil was limed to various pH levels and maize was grown for 10
weeks. The largest growth response occurred when the soil pH was raised from 4.3
to 5.0 by liming (1.3 metric ton/ha). The highest yield was obtained when the
soil pH was between 5.5 to 6.0.
77:053-033
PHYSICAL AND CHEMICAL PARAMETERS AFFECTING TRANSPORT OF CS IN ARID WATERSHEDS,
McHenry, J.R., and Ritchie, J.C.
United States Department of Agriculture, Agricultural Research Service, Sedi-
mentation Laboratory, Oxford, Mississippi.
Water Resources Research, Vol. 13, No. 6, p 923-927, December 1977- 6 tab, 8 ref.
Descriptors: Watersheds, Watershed management. Soils, Sediments, Sedimentation,
Nitrogen, Rainfall, Cation exchange.
The occurrence and amount of fallout 137Cs were determined in 12 watersheds in the
arid southwestern United States. The factors believed to influence the distribu-
tion of 137Cs in the watershed soils and in the reservoir sediments were investi-
gated by using stepwise regression techniques. Seventeen parameters, in the case
of soils, and 21 parameters, in the case of sediments, were used in the study.
Ninety percent of the variation in the 137Cs content of soils, per unit weight,
could be predicted in terms of the percentage of soil nitrogen, the R factor
(rainfall intensity) of the universal soil loss equation, the percentage of sand
in the soils, and the soil cation exchange capacity.
77:05B-034
MOVEMENT OF THREE HERBICIDES IN A FINE SAND AQUIFER,
Schneider,- A.D., Wiese, A.F. , and Jones, O.R.
United States Department of Agriculture, Agricultural Research Service, Bushland,
Texas 79012.
Agronomy Journal, Vol. 69, No. 3, p 432-436, May-June, 1977- 8 fig, 1 tab, 9 ref.
Descriptors: Groundwater,- Water pollution, Water quality, Herbicides, Aquifers,
Sampling, Hydrodynamics.
In order to determine movement of farm chemicals that might accidentally contami-
nate underground water supplies, low concentrations of three herbicides and NaN03
as a tracer were injected into a sand aquifer through a dual-purpose well.
Herbicides used were picloram, atrazine, and trifluralin. Recharge by injection
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continued for 10 days at an average rate of 81.8 cu m/hour. After a 10-day
pause, the well was pumped for 12 days to determine if the herbicides and tracer
could be recovered. Water samples were pumped from observation wells located
9, 20, and 45 m from the dual-purpose well. Herbicides were detected in the 9-
and 20-m distant wells, but none of the herbicides or the tracer was detected
in the 45-ra distant well.
77:058-035
RESIDUAL NITRATE AND MINERALIZABLE SOIL NITROGEN IN RELATION TO NITROGEN UPTAKE
BY IRRIGATED SUGARBEETS,
Stanford, G., Carter, J.N., Westermann, D.T., and Meisinger, J.J.
Agricultural Environmental Quality Institute, Beltsville, Maryland 20705.
Agronomy Journal, Vol. 69, No. 2, p 303-308, March-April, 1977. 4 fig, 6 tab.
12 ref.
Descriptors: Sugar beets, Idaho, Nitrogen, Fertilizers, Fertilization, Irrigation,
Soil water, Mineralization, Temperatures, Soil moisture.
Previously reported studies on N fertilization of sugarbeets in southern Idaho
revealed considerable variation among sites in amounts of residual soil N03 and
N mineralized during short-term laboratory incubations. Consequently, the amount
of N fertilizer needed to achieve near-maximum yields of sucrose differed markedly.
The purpose of this study was to determine the feasibility of estimating amounts
of N mineralized in the root zone during the season, taking into account site
variations in temperature and soil water regimes. Residual soil N03(-)-N and
mineralizable N to approximate rooting depth were estimated for 21 field sites in
1971 and six sites in 1972. The relative contributions of these two N sources to
total N uptake by the crop, in the absence of applied fertilizer N, were then
assessed.
77:058-036
SEASONAL ANHYDROUS AMMONIA COMPARISON FOR CORN WITH AND WITHOUT A NITRIFICATION
INHIBITOR,
Boswell, F.C.
Georgia University, Department of Agronomy, College of Agricultural Experiment
Stations, Georgia Station, Experiment, Georgia.
Agronomy Journal, Vol. 69, No. 1, p 103-106, January-February, 1977. 6 tab, 21
ref.
Descriptors: Ammonia, Corn, Nitrification, Nitrogen, Crop production. Leaching.
With increased interest in "off-season" N application and emphasis on better
management of N with respect to environmental pollution and economic considerations,
information is needed relative to seasonal anhydrous ammonia comparisons for corn
with and without an inhibitor. Field studies compared rates of N applied preplant
with December application either with or without the nitrification inhibitor, N-
SERVE, to corn on a Coastal Plain soil. The nitrification inhibitor did not affect
yield, number of ears, average ear weight, and percent N, P, K, Ca, and Mg in the
tissue or concentrations of various other elements in tissue sampled early in the
growing season, at early silking, or in corn grain. Both low (90 kg/ha) and high
(180 kg/ha) N levels increased yields above check plots (zero N) when applied in
December for the three-year average but both levels were significantly less than
the high N level applied preplant.
77:058-037
QUALITY OF IRRIGATION WATER AND SURFACE RETURN FLOWS FROM SELECTED AGRICULTURAL
LANDS IN NEVADA DURING THE 1974 IRRIGATION SEASON,
Miller, W.W., Guitjens, J.C., and Mahannah, C.N.
Nevada University, Max C. Fleischmann College of Agriculture, Reno, Nevada.
Journal of Environmental Quality, Vol. 6, No. 2, p 193-200, April-June, 1977.
6 fig, 3 tab, 26 ref.
Descriptors: Return flow, Water quality, Irrigation water, Nevada, Water quality
control, Tailwater, Phosphorus, Pollutants.
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Agriculture has been identified as a major contributor of pollutants to surface
waters. The purpose of this investigation was to gain knowledge of pollutants
and pollutant loads carried in surface return flows to receiving waters. Infor-
mation of this nature is needed by those agencies having administrative responsi-
bility for water quality control. Quantitative and qualitative measurements of
irrigation applications (head water) and surface return flows (tailwater) were
conducted on four sites at three locations in the Carson Valley area of Nevada to
investigate the change in pollutant loads of surface waters entering the leaving
agricultural units. Dissolved oxygen (DO), biochemical oxygen demand (BOD), total
dissolved solids (TDS), NO3(-)N, P04(-)P, S04, and turbidity were considered as
major constituents of water quality. Concentrations were combined with flow
volumes to compute the constituent loading per irrigation and net infiltrated
amounts or seasonal contributions in the surface return flow. Phosphorus and
BOD were found to be the major agricultural pollutants contributed by irrigation
surface return flows. New infiltrated amounts of TDS, N03(-)N, and other soluble
constituents were recorded. Dissolved oxygen concentrations in head and tailwaters
were found to be critically low. River standards for DO might be better expressed
as a maximum permissible dissolved oxygen deficit for water at a given temperature
carrying a given amount of BOD. Additional investigations should be undertaken to
delineate possible interactions among pollutant constituents. Water quality vari-
ations of individual samples should be expressed in statistical terms so that
it is possible to identify pollutant interdependences and to establish an opti-
mized sampling frequency.
77:05B-038
A STEADY-STATE CONCEPTUAL NITROGEN MODEL FOR ESTIMATING NITROGEN EMISSIONS FROM
CROPPED LANDS,
Tanji, K.K., Fried, M., and Van De Pol, R.M.
Food and Agriculture Organization, International Atomic Energy Agency, Vienna,
Austria.
Journal of Environmental Quality, Vol. 6, No. 2, p 155-159, April-June, 1977.
2 fig, 5 tab, 5 ref, 1 append, 40 equ.
Descriptors: Nitrogen, Model studies. Leaching, Corn, Crop production, Fertilizers,
Fertilization.
Details of a conceptual nitrogen model are presented. The model is based upon the
principles of mass balance and steady state. It considers both water and N flows
into and out of the crop root zone. Illustrative computations are given for
estimating steady-state N leaching losses from two cornfield sites and comparisons
are made with measured values. This model may be applied to other crops or cropping
practices.
77:058-039
LYSIMETER MEASUREMENTS OF NITRATE AND CHLORIDE LOSSES FROM SOIL UNDER CONVENTIONAL
AND NO-TILLAGE CORN,
Tyler, D.D., and Thomas, G.W.
Kentucky University, Lexington, Kentucky 40506.
Journal of Environmental Quality, Vol. 6, No. 1, p 63-66, January-March, 1977.
6 fig, 15 ref.
Descriptors: Lysimeters, Nitrates, Chlorides, Corn, Soils, Soil investigations,
Soil water movement, Leaching, Salts, Nitrogen, Mulching.
Salt and water movement was studied using steel pan lysimeters in the field under
corn grown in killed sod and with conventional tillage. The study was done to
determine the actual leaching losses of nitrogen under the two tillage systems.
Losses of nitrate nitrogen and chloride used as a tracer of nitrate ion were
higher under the no-tillage system as measured in the leachate collected^after
rainfall. This loss could occur within 1 to 2 months after the application^of_
the nitrogen. Concentrations of nitrate and chloride ions in the leachate indi-
cated that these mobile, surface-applied anions could be washed into natural soil
cracks and channels and flow much deeper into the soil than predicted by miscible
displacement theory.
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77:05B-040
PREDICTING EFFECTS OF SULFURIC ACID ON QUALITIES OF IRRIGATION AND DRAINAGE WATERS
IN CALCAREOUS SOILS,
Miyamoto, S.
Texas A & M University Agricultural Research Center, 1380 A and M Circle, El
Paso, Texas 79927.
Journal of Environmental Quality, Vol. 6, No. 1, p 12-18, January-March, 1977.
3 fig, 4 tab, 24 ref.
Descriptors: Sulfuric acid, Calcareous soils, Irrigation water, Drainage water,
Water quality, Simulation analysis, Model studies.
Considerable quantities of sulfuric acid are being utilized in the southwestern
United States for soil and water treatment. Future acid production may exceed
demand and thus require disposal in some manner. Acid application or disposal
to soils and water raises a question concerning effects on water quality. A numeri-
cal method is thus presented for predicting the effects of H2S04 on qualities of
irrigation and drainage waters, excluding trace elements, in calcareous systems.
The method is based on known relations between ion equilibria and the solubility
of calcite, magnesite, and gypsum. Computed results are presented for acid
applied to waters or to soils under several hypothesized conditions, and compared
with some reported laboratory or lysimeter data. Results indicate: (1) the
numerical method is a promising tool, but requires further experimental verifica-
tion; (2) acid effects on water quality depend strongly on C02 partial pressure
and properties of soils and water, besides application rates; and (3) the assumption
that acid application produces equivalent amounts of soluble salts is an over-
simplification .
77:058-041
FERTILIZER AND PESTICIDE MOVEMENT FROM CITRUS GROVES IN FLORIDA FLATWOOD SOILS,
Mansell, R.S., Calvert, D.V., Stewart, E.H., Wheeler, W.B., and Rogers, J.S.
Florida University, Gainesville, Florida 32611.
Publication No. EPA-600/2-77-177, August 1977. 133 p, 73 fig, 35 tab, 53 ref.
1 append.
Descriptors: Fertilizers, Fertilization, Pesticides, Florida, Soil properties.
Irrigation water, Water quality, Soil management. Soil moisture. Soil water.
Concentrations and discharge amounts of N03-N, P04-P, 2, 4-D herbicide, terbacil
herbicide, and chlorobenzllate acaricide were determined in surface and subsurface
drainage waters from a citrus grove located in an acid, sandy flatwood soil of
southern Florida. The citrus grove received routine applications of fertilizer,
pesticide, and irrigation water as needed.
77:058-042
RELATIVE MOVEMENT OF BROMIDE AND NITRATE IN SOILS UNDER THREE IRRIGATION SYSTEMS,
Onken, A.B., Wendt, C.W., Hargrove, R.S., and WiIke, O.C.
Texas A & M University Agricultural Research and Extension Center, Lubbock, Texas.
Soil Science Society of America Journal, Vol. 41, No. 1, p 50-52, January-
February, 1977. 4 fig, 4 ref.
Descriptors: Bromides, Nitrates, Soils, Soil properties, Corn, Irrigation, Irri-
gation practices. Irrigation effects. Furrow irrigation, Sprinkler irrigation.
Surface irrigation, Anions, Leaching, Fertilizers, Irrigation water.
Bromide has desirable characteristics as an indicator of nitrate movement in soils,
although it has not been tested under field conditions. We studied its field
applicability by growing sweet corn on plots to which a mixture of sodium nitrate
and sodium bromide were band applied. Irrigation was accomplished by either
furrow, sprinkler or subirrigation. Nitrate and Br(-) moved together in the
soil profile, but the concentration of NO3(-) and Br(-) were quantitatively
unrelated. The lack of a quantitative relationship was probably due to (1) N03(-)
-N was the sum of that already present, that from mineralization of organic matter,
plus that applied while bromide came only from that applied, and (2) N03(-)-N
from all three of these sources and Br(-) were removed from the soil at different
rates by the growing crop.
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77:05B-043
FIELD MEASUREMENTS OP AMMONIA VOLATILIZATION FROM SURFACE APPLICATIONS OF AMMONIUM
SALTS TO A CALCAREOUS SOIL,
Hargrove, W.L., Kissel, D.E., and Fenn, L.B.
Texas Agricultural Experiment Station, P.O. Box 748, Temple, Texas 76501.
Agronomy Journal, Vol. 69, No. 3, p 473-476, May-June, 1977. 1 fici 2 tab
16 ref.
Descriptors: Ammonium, Ammonium salts, Soils, Soil investigations, Calcareous
soils, Nitrogen, Fertilizers, Fertilization.
Many laboratory experiments have been conducted to study ammonia volatilization
from N fertilizers, but few experiments have been conducted under field condi-
tions. The objective of this study was to evaluate ammonia volatilization in
the field from ammonium sulfate and ammonium nitrate applied to the surface of
a calcareous soil. Houston Black Clay, that belongs to the fine, montmorilloni-
tic, thermic family of Udic Pellusterts. Volatilization was evaluated indirectly
by measuring N uptake by Coastal bermudagrass and directly by measuring ammonia
as it volatilized. In the field plot study, estimated losses ranged from 3 to
10% of the applied N for ammonium nitrate, from 36 to 45% of the applied N for
pelleted ammonium sulfate, and from 25 to 55% of the applied N for liquid ammonium
sulfate at rates of 140 and 280 kg N/ha.
77:05B-044
THE WELLTON-MOHAWK: WHERE NECESSITY IS TEACHING THEM TO SAVE WATER,
Ross, R.
Irrigation Age, Vol. 11, No. 8, p 30, May-June, 1977. 1 fig.
Descriptors: Water conservation, Irrigation effects, Salinity, Saline water,
Mexico.
In 1973, an agreement was signed between Mexico and the United States that could
have far reaching influences on how southwestern American farmers irrigate.
Leaders of the two nations signed documents which said that by a given date,
the level of salts in the Colorado River, as it enters Mexico, would be held to
certain "reasonable" limits. Reaching those limits will require new irrigation
technology in the 64,000-acre Wellton-Mohawk Irrigation and Drainage District,
east of Yuma, Arizona. And what those farmers learn, to satisfy the agreement,
could be applicable to many other arid areas within the United States and world-
wide, as water and energy demands increase.
77:058-045
MASS BALANCE MONITORING OF LAND APPLICATION SITES FOR WASTEWATER RESIDUALS,
Smith, J.L., McWhorter, D.B., Trout, T.J.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 2,
Paper No. 76-2065, p 309-312, March-April, 1977. 4 fig, 2 tab, 8 ref.
Descriptors: *Waste water disposal, *Sludge disposal, *Soils, Groundwater, Heavy
metals, Leachates, Leaching, Groundwater movement, Soil amendments, Wastes,
Sewage sludge, Water table, Water levels, On-site investigations, Soil contami-
nation, Water pollution, Pollutants, Monitoring.
The soil can serve as a receiving medium and a final form of treatment by removing
and decomposing various constituents in the sludge. Land application, when
properly controlled, incorporates ultimate disposal with resource recovery. This
paper proposed use of the mass balance concept for predicting groundwater quality
and buildup of heavy metals in soils due to application of wastewater sludges.
The concept is based on the principle of continuity of mass and an idealization
of the flow system. Data from the Boulder, Colorado municipal sludge applica-
tions site were used to illustrate practical application of the concept. Mass
balance reduces the lag time between application and measurement^and uses_mea-
surement made prior to dilution of potential contaminants. A major deficiency
in the concept is that, while it predicts a buildup of heavy metals in the
soil, it does not indicate their availability to plants. However, other research
207
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has indicated that there is no cumulative effect of heavy metals and that plant
uptake is not normally a problem in soils having near neutral pH.
77:05B-046
QUALITY ASPECTS OF AGRICULTURAL RUNOFF AND DRAINAGE,
The Task Committee on Agricultural Runoff and Drainage of the Water Quality
Committee of the Irrigation and Drainage Division.
American Society of Civil Engineers, New York, New York.
Journal of the Irrigation and Drainage Division, Vol. 103, No. IR4, p 475-495,
December 1977. 4 tab, 67 ref, 1 append.
Descriptors: Agriculture, Drainage, Eutrophication, Pesticides, Nutrients, Runoff,
Sedimentation, Water management (Applied), Water pollution, Water quality.
In this report, the American Society of Civil Engineers Task Committee on Agri-
cultural Runoff and Drainage has summarized the literature and research findings
with respect to sources of pollutants, nature of downstream impacts, and rela-
tionships between pollutant loads and certain physical variables. Agricultural
discharges from nonirrigated lands are significant contributors of nitrogen,
phosphorus, and pesticides to downstream receiving waters. State-of-the-art
knowledge indicates that management practices directed toward control of erosion,
control of runoff, and management of fertilizer and pesticide application can
reduce total pollutant load carried off-site from agricultural lands. The
development of on-site discharge water quality control measures, as contemplated
under PI 92-500, must be predicated on detailed surveys of a more specific nature
due to the high degree of variability in the factors influencing water-borne
pollutant transport.
77:053-047
DIMENSIONLESS SOLUTIONS OF BORDER-IRRIGATION ADVANCE,
Katopodes, N.D., and Strelkoff, T.
California University, Department of Land, Air and Water Resources, Water
Science and Engineering Section, Davis, California.
Journal of the Irrigation and Drainage Division, Vol. 103, No. IR4, p 401-417,
December 1977. 14 fig, 11 ref, 30 equ. 2 append.
Descriptors: Computers, Hydraulics, Hydrodynamics, Irrigation engineering,
Mathematical models. Surface irrigation, Model studies.
The equations of border-irrigation flow are written in dimensionless form and
solved numerically at three different levels of mathematical approximation. For
the advance phase three independent parameters exist: the Froude number based
on normal depth, the dimensionless exponent of the Kostiakov infiltration equation,
and a dimensionless parameter determining the deviation of flow conditions from
normal. It is shown both by order of magnitude analysis and from the results
of the numerical computation that the inertia terms in the governing equations
are unimportant for border flow (Froude number approximately zero). The model
governed by the remaining two parameters, the zero-inertia model, is used to
generate dimensionless advance trajectories and related information for all
practical combinations of these two parameters. An additional advance trajectory
is computed for each value of the dimensionless infiltration exponent using the
normal-depth model to show the range of applicability of the latter.
77.-05B-048
SOLUBLE AND SEDIMENT NITROGEN LOSSES AS RELATED TO LAND USE AND TYPE OF SOIL IN
EASTERN CANADA,
Neilsen, G.H., and MacKenzie, A.F.
Macdonald College, Ste. Anne de Bellevue, Department of Renewable Resources,
Quebec, Canada.
Journal of Environmental Quality, Vol. 6, No. 3, p 318-321, July-September, 1977.
2 fig, 4 tab, 25 ref.
Descriptors: *Agrlcultural runoff, *Nitrogen compounds, *Sediments, *Runoff,
*Agricultural watersheds, Water quality. Leaching, Water pollution sources,
Nitrates, Nutrients, Pollutants, Water analysis, Water chemistry, Nitrites,
Nitrogen, Analytical techniques, Canada, Soil analysis.
208
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In order to assess the amounts and types of nitrogen lost in agricultural drainage,
seven agricultural watersheds, with a range of land use patterns and types of
soil in southwestern Quebec and southeastern Ontario, were selected, and measure-
ments of discharge rates, soluble inorganic nitrogen, and sediment Kjeldahl
nitrogen were made during 1974-75. Correlations of the losses with land use
and kind of soil were used to identify critical watershed factors affecting
nitrogen loss. Soluble inorganic N concentrations in streams did not exceed
3.5 micrograms/ml. No watershed lost more than 5 kg/ha soluble N, except for
the watershed with the maximum corn acreage (33%), which lost 22.8 kg N/ha per
year. The pronounced significance of spring melt runoff was demonstrated by
the movement of from 56 to 100% of annual soluble N from the monitored watersheds
during March, April, and May. Sediment was a major transporter of N in the
area, moving from 22 to 67% of total watershed N. Watersheds with greater corn
acreage and relatively impermeable soils lost more soluble N, while watersheds
with more organic soils and greater cultivated area lost more sediment N.
77:053-049
QUALITY OF WATER DISCHARGED FROM THREE SMALL AGRONOMIC WATERSHEDS IN THE MAUMEE
RIVER BASIN,
Jones, L.A., Smeck, N.E., and Wilding, L.P.
Ohio Agricultural Research and Development Center, Wooster, Ohio 44691.
Journal of Environmental Quality, Vol. 6, No. 3, p 296-302, July-September, 1977.
1 fig, 5 tab, 17 ref.
Descriptors: *Sediments, *Lake Erie, *Water pollution sources, *Water quality.-
*Agricultural runoff, *Soil analysis. Geology, Glacial drift, Analytical
techniques, Sediment transport, Particle size, Water pollution, Calcium, Magnesium,
Agricultural watersheds. Sodium, Po'tassium, Soil chemistry, Lakes, Ohio.
The investigation was aimed at evaluating the quality of water and the charac-
teristics of sediments leaving three nearly level watersheds in the Lake Plain
sector of the Maumee River Basin during a 32-month period as a function of soils
comprising'the watersheds. Each watershed consisted of a soil of major extent
(Paulding, Hoytville, or Millgrove) developed from the three most extensive geo-
logic deposits present in the basin: lacustrine, glacial till, and beach sand,
respectively. The results indicated that water quality is a function of soil
characteristics, discharge, and year. The fine-textured Paulding watershed
yielded lower concentrations of calcium, magnesium, and bicarbonate ions than
the other two watersheds, but higher concentrations of sodium, potassium, and
phosphorus. High concentrations of the latter three elements were attributed to
the presence of septic tank effluent in the drainage ditch samples. The Paulding
watershed also yielded the highest concentration of sediment, which implies that
nearly level watersheds of the basin, particularly fine-textured watersheds, may
represent significant contributors of sediment entering the Maumee River.
Flocculation of clay minerals in the sediments during fluvial transport resulted
in increasing particle size and changing mineralogy on moving downstream from
headwater areas.
77:05B-050
NITRATE-NITROGEN AND CHLORIDE MOVEMENT THROUGH UNDISTURBED FIELD SOIL,
Shuford, J.W., Fritton, D.D., and Baker, D.E.
Alabama A and M University, Normal, Alabama.
Journal of Environmental Quality, Vol. 6, No. 3, p 255-259, 1977. 1 fig, 7 tab,
10 ref.
Descriptors: *Soil water movement, *Dispersion, *0n-site tests, *Pennsylvania,
*Nitrogen, Soil water, Nitrates, Chlorides, Mixing, Percolation, On-site
investigations, Movement, Irrigation, Analytical techniques, Analysis, Sampling,
Ion transport, Ions.
Results were presented from a field study conducted to determine whether large
pores represent a major pathway for N03-N and Cl movement through undisturbed
soil. A soil containing 410 ppm NO3-N and Cl as KN03 and KC1 was added to 3
experimental field plots enclosed by wooded barriers to prevent runoff. Initial
and final soil samples were taken at various profile depths for ion analyses.
Most of the N03-N and Cl added in solution moved vertically with the water
through the profile. Ion movement was influenced by large soil pores between
209
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structural units. A fourth field plot was designed to compare field-measured
N03-N and Cl concentrations with theoretical calculations, using time-dependent
water flow velocity and dispersion equations. Soil solution samples were taken
for ion analyses. Due to the incomplete mixing of water and ions with all soil
pores, theoretical equations did not completely explain the field-measured N03-N
and Cl distribution.
77:058-051
EFFECT OF SUSPENDED PARTICLES AND THEIR SIZES ON NITRIFICATION IN SURFACE WATER,
Kholdebarin, B., and Oertli, J.J.
Pahlavi University, Shiraz, Iran.
Journal Water Pollution Control Federation, Vol. 49, No. 7 p. 1693-1697, July
1977. 2 fig, 10 ref.
Descriptors: *Nitrification, California, *0xidation, *Surface waters, *Particle
size, Ammonium compounds, Suspended particles.
Results of studies with water samples from the Whitewater River in Southern
California clearly indicate the importance of the presence of suspended parti-
culates and of particle size in nitrifying bacteria in surface water. While
organisms can function well in media lacking measurable suspended solid materials,
their activities will be enhanced as the amount of particulates increases in
the solutions; the stimulating effect of particles is largely caused by their
acting as a physical support for the proliferation of the nitrifying bacteria,
rather than as base exchange sites for the substrates used in nitrification
processes. Also, it appears particles as large or larger than the organism
are most efficient in stimulating the nitrification process, contradicting findings
of earlier studies which concludes that particles with diameters in excess of
0.7 microns are not essential for rapid biological nitrification in aquatic
systems.
77:05B-052
A MODEL FOR THE TRANSPORT OF PESTICIDES IN SOIL WITH DIFFUSION-CONTROLLED RATES OF
ADSORPTION AND DESORPTION,
Leistra, M.
Laboratory for Research on Insecticides, Marijkeweg 22, Wageningen, The
Netherlands.
Agriculture and Environment, Vol. 3, No. 4, p 325-335, October 1977. 5 fig, 1 tab,
13 ref.
Descriptors: Adsorption, Model studies, Soils, Soil investigations. Rainfall,
Simulation analysis. Pesticides.
The downward movement of a pesticide in soil, caused by different rainfall patterns,
was simulated in a computation model. The movement occurred in the mobile region
of a hypothetical soil system by convection together with hydrodynamic dispersion,
and by diffusion. Lateral transport took place by diffusion into and out of a
soil region with a stagnant liquid phase. With 40 mm of rainfall in 2 days,
lateral diffusion distances of a few mm or more caused substantial deviation from
the concentrationdepth relationship for equilibrium adsorption. With 40 mm of
rainfall scattered over 20 days, lateral diffusion distances up to a few mm had
little effect, but those of about 10 mm or more had a very strong influence. The
initial condition near the soil surface was extemely important. When the pesti-
cide was initially present in the mobile region, overall mobility was comparatively
great. Mobility was found to be much lower than with instantaneous adsorption
and desorption, when the initial condition was equilibrium between the mobile
and stagnant regions near the soil surface.
77:05B-053
A LABORATORY STUDY ON THE ROLE OF STREAM SEDIMENT IN NITROGEN LOSS FROM WATER,
Sain, P., Robinson, J.B., Stammers, W.N., Kaushik, N.K., and Whiteley, H.R.
National Research Council of Canada, Department of Environmental Biology,
University of Guelph, Guelph, Ontario, Canada.
Journal of Environmental Quality, Vol. 6, No. 3, p 274-278, July-September, 1977.
4 fig, 4 tab, 14 ref.
210
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Descriptors: Laboratory tests. Sediments, Sedimentation, Nitrogen, Nitrates
Denitrification, Temperature, Water quality, Streams. '
Laboratory experiments were conducted on samples of sediment collected from a
stream having an appreciable input of nitrate at its source. Earlier work had
shown that the water lost much of the nitrate as it moved downstream, presumably
by denitrification. Columns of sediment were reconstituted in plexiglass tubes,
overlain with water containing nitrate, and incubated at 10, 15, or 22C. The
water was aerated with a helium-oxygen mixture. Nitrate concentration decreased
rapidly but the rate varied with temperature and depth of sediment. At 22C, in
water overlying 10-cm columns of sediment, over 90% of the nitrate was removed
in three weeks from a solution originally containing 10 mg/liter nitrate-N.
Nitrate disappeared less rapidly at lower temperatures and when sediment columns
were less than 5 cm deep. It was concluded that in columns less than 5 cm deep
and at low temperatures nitrate diffused to the bottom of the columns, while
columns 5 cm deep or more were effectively of infinite depth. Because of the
interdependence of diffusion from the liquid phase into the sediment and deni-
trification, it is not possible to infer kinetics of denitrification in these
experiments. It appeared that denitrification in these columns proceeded at
a rate compatible with observations made previously in the stream from which
the sediment originated.
77:05B^054
PARTITIONING AND TRANSPORT OF LEAD IN LAKE WASHINGTON,
Baier, R.W., and Healy, M.L.
Duke University, Department of Chemistry, Marine Laboratory, Beaufort, North
Carolina 28516.
Journal of Environmental Quality, Vol. 6, No. 3, p 291-296, July-September,
1977. 9 fig, 3 tab, 13 ref.
Descriptors: Lead, Runoff, Sediments, Sedimentation, Model studies, Adsorption,
Absorption, Limnology.
Input of lead to Lake Washington appears to result from the settling of airborne
Pb onto surface waters and the washing of terrestrial accumulations to the lake
as runoff. Some of the Pb received by the lake is associated with particles
that sink, while the remainder leaves the lake with the overflow. The range in
Pb concentration during two years of sampling was 0.04 to 6.6 ppb. The path
of Pb to the sediments is not direct but involves cycling through both liquid
and solid phases. Over 70% of the total Pb entering the lake is retained by
sediment. Lead in top layers of sediment ranged from 242- ppm near a heavily
used bridge to 4 ppm near the major tributary of the lake. A simple compartment
model accounts for some of the interchanges between dissolved and particulate
forms of Pb through the processes of adsorption, absorption, and complexation.
The time required to achieve steady-state conditions for the model is comparable
to the yearly flushing period. Large shifts in the annual timing of flushing
and mixing are encountered because of meteorological changes.
77:05B-055
NITRATE DISTRIBUTION AND VARIABILITY IN IRRIGATED FIELDS OF NORTHEASTERN COLORADO,
Ludwick, A.E., Soltanpour, P.N., and Reuss, J.O.
Colorado State University, Department of Agronomy, Fort Collins, Colorado 80523.
Agronomy Journal, Vol. 6, No. 4, p 710-713, July-August, 1977. 1 fig, 6 tab,
16 ref.
Descriptors: Nitrates, Irrigation, Irrigation effects, Colorado, Fertilizers,
Fertilization, Nitrogen, Nutrients, Soil profiles, Sampling.
Fertilizer N recommendations in the Great Plains and Western United States are
commonly based on soil NO3- tests, although N03- content within soil profiles^
is subject to rapid change. The purpose of this study was to evaluate N03- distri-
bution within diverse soil profiles and determine NO3- changes occurring over
winter. Twenty-six irrigated farm fields were systematically sampled in 1974 and
1975 by dividing them into 61 x 61 m grids (0.37 ha) and sampling to a 120-cm
depth by 30-cm increments. Eleven fields were resampled for fall versus spring
comparisons. Nitrate content tended to be greatest in the surface 30-cm and
decrease with depth; only three fields deviated markedly from the general pattern.
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77:05B-056
UPTAKE BY BARLEY OF WATER TABLE-OR SURFACE-APPLIED CADMIUM,
Kirkham, M.B.
Oklahoma State University, Department of Agronomy, Stillwater, Oklahoma.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1125-1129,
November-December, 1977. 3 fig, 3 tab, 19 ref.
Descriptors: *Cadmium, *Absorption, *Barley, Laboratory tests, Soil contamination,
Plant physiology, Water pollution, Pollutants, Path of pollutants, Groundwater,
Leaching, Leachate, Effluents, Drainage, Water table, Soil science, Cadmium uptake.
Solution of Cd were placed for 66 days at the bottom or top of columns (42-cm
long by 15-cm diam) containing find sandy loam soil, half of which were planted
with barley and half of which were bare, to determine rate of movement upward
or downward of Cd. Three solutions with Cd, as CdS04, were used: distilled
water with 0.1 microgram/ml Cd; distilled water with 10 microgram/ml Cd;
secondary effluent with 10 microgram/ml Cd. An average of 200 ml/day was added
to the top or bottom of columns with plants; there was not drainage water with
top additions. An average of 100 or 50 ml/day was added to the top or bottom,
respectively, of columns without plants. Drainage water, which collected at the
bottom of columns without plants and watered from the top, was analyzed daily
for Cd. Plants and soil were analyzed weekly for Cd concentration. In less than
seven days, Cd applied at the surface moved to the bottom and Cd applied at the
bottom moved to the surface. At harvest, plants treated with Cd at the bottom
contained up to three times more Cd than plants treated with Cd at the top
because roots of plants with Cd at the bottom contained higher concentrations
of Cd than roots of plants in columns with Cd at the top. Columns without
roots had higher concentrations of extractable Cd than columns with roots.
Concentrations of Cd in leachate from columns receiving 10 microgram Cd/ml
effluent were about two times higher than concentrations of Cd in leachate from
columns receiving 10 microgram Cd/ml water. The results showed that barley
roots more readily absorbed Cd placed in a shallow water table than Cd placed
in the soil surface.
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SECTION XX
WATER QUALITY MANAGEMENT AND PROTECTION
EFFECTS OF POLLUTION (GROUP 05C)
77:05C-001
QUALITY OF WATER FOR IRRIGATION,
Ayers, R.S.
California University, Department of Water Science and Engineering, Davis,
California.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR2, p 135-154, June 1977. 5 tab, 13 ref.
Descriptors: Water quality, Salinity, Irrigation, Irrigation effects, Crop
production. Agriculture, Leaching, Electrical conductance.
Water quality means different things to different people. Quality usually denotes
"suitability" for use and is difficult to evaluate except in terms related to its
specific use. For irrigation, water suitability is related to its effect on soils
and crops, and on the management that may be necessary to control or compensate
for a water quality related problem.
77:05C-002
IRRIGATION WATER QUALITY EVALUATION,
Christiansen, J.E., Olsen, E.G., and Willardson, L.S.
Utah State University, Department of Agricultural and Irrigation Engineering,
Logan, Utah.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR2, p 155-169, June 1977. 4 fig, 6 tab, 22 ref.
Descriptors: Water quality.- Irrigation, Irrigation water. Salinity, Saline water,
Electrical conductance, Crop production, Irrigation practices.
Irrigation water quality is very seldom adequately defined. The term is sometimes
used to mean only the salinity expressed as total dissolved solids, TDS, in
milligrams per liter or the equivalent, parts per million. The TDS is determined
by evaporating a given volume of water and weighing the residue. Most often the
salinity is determined by measuring the electrical conductivity, EC (or specific
conductance as it sometimes is called), and reporting it in millimhos per centi-
meter at 25 degrees C or in micromhos per centimeter. Such determinations of
irrigation water quality are useful but are too limited in scope to be completely
satisfactory for making dependable decisions on the usefulness of a particular
water for irrigation.
77:05C-003
THE PHOSPHORUS STATUS OF EUTROPHIC LAKE SEDIMENTS AS RELATED TO CHANGES IN LIMNOLO
GICAL CONDITIONSPHOSPHORUS MINERAL COMPONENTS,
Wildung, R.E., Schmidt, R.L., and Routson, R.C.
Battelle, Pacific Northwest Laboratory, Richland, Washington 99352.
Journal of Environmental Quality, Vol. 6, No. 1, p 100-104, January-March, 1977.
1 fig, 3 tab, 21 ref.
Descriptors: Phosphorus, Limnology, Sediments, Sedimentation, Eutrophication,
Water quality.
Studies of the relationship between limnological factors and changes in the P
status of noncalcareous sediments of a eutrophic lake previously indicated that_
changes in sediment inorganic P were directly related to the biological producti-
vity of the surface waters. This relationship was particularly pronounced in a
shallow bay where sediment P decreased with lake phytoplankton growth and
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increased with their decline. The present studies were undertaken to identify
the inorganic P components responsible for these changes using chemical
techniques for characterization of P in sediments where changes occurred.
77:050004
STERILITY IN RICE CULTIVARS AS INFLUENCED BY MSMA RATE AND WATER MANAGEMENT,
Wells, B.R., and Gilmour, J.T.
University of Arkansas, Department of Agronomy, Fayetteville, Arkansas 72701.
Agronomy Journal, Vol. 69, No. 3, p 451-454, May-June, 1977. 3 tab, 16 ref.
Descriptors: Rice, Crop production, Arkansas, Cotton, Soils, Soil investigations,
Soil water, Saturated soils.
In recent years an expansion of rice acreage in Arkansas has resulted in rice
being produced on soils with a history of cotton production. Most of these
cotton soils have had repeated applications of monosodium methanearsonate (MSMA)
as a herbicide. There is some evidence that arsenical residues in the soil
can lead to sterility in rice. In an effort to answer this question, a field
experiment was conducted on a Crowley silt loam soil in 1975 to evaluate the
influence of MSMA on plant growth and yield of rice.
77:05C-005
EFFECTS OF IRRIGATION METHODS ON GROUNDWATER POLLUTION BY NITRATES AND OTHER
SOLUTES,
Wendt, C.W., Onken, A.B., Wilke, O.C., and Lacewell, R.D.
Texas Agricultural Experiment Station, Route 3, Lubbock, Texas 79401.
Publication No. EPA-600/2-76-291, December 1976. 330 p, 197 fig, 46 tab, 23 ref.
Descriptors: Irrigation, Fertilizers, Nitrogen, Isotopes, Water pollution, Soil
water.
Sprinkler irrigation, furrow irrigation, subirrigation, automated subirrigation,
criteria for applying irrigation water, methods of applying fertilizer and sources
of fertilizer were investigated as to their potential to decrease possible pollution
from nitrate and other solutes in a loamy fine sand soil overlying a shallow
aquifer in Knox County, Texas. Less nitrate-nitrogen was available for leaching
in subirrigation systems than furrow and sprinkler systems. Less, irrigation water
was applied with automated subirrigation systems than with the other irrigation
systems. However, crop water requirement was not significantly changedthe soil
water was more efficiently used. Fertilizer remained in the root zone if the
water applied was based on potential evapotranspiration and leaf area regardless
of the irrigation system or the criteria used to apply the irrigation water.
Banded fertilizers moved differently in the different irrigation systems. Sub-
irrigation has the possibility of having irrigation return flow with lower con-
centrations of other solutes than sprinkler or furrow systems. Banding fertilizer
in the bed was superior to banding below the level of the water, furrow and
applications in the irrigation water relative to quality of irrigation return
flow. No other source of nitrogen fertilizer was indicated to be superior.
Current fertilization practices are not causing major increases in the nitrate-
nitrogen level in the aquifer.
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SECTION XXI
WATER QUALITY MANAGEMENT AND PROTECTION
WASTE TREATMENT PROCESSES (GROUP 05D)
77:050-001
RECYCLING AGRICULTURAL RUNOFF,
Walker, P.N., and Lembke, W.D.
Illinois University, Department of Agricultural Engineering, Urbana-champalgn,
Illinois.
Available from the National Technical Information Service, Springfield, Virginia,
22161 as PB-264 578, Illinois Water Resources Center, Urbana, Illinois, Research
Report No. 119, January 1977, 88 p. 11 fig, 6 tab, 72 ref.
Descriptors: Irrigation, *Water reuse, "Impervious soils, "Illinois, *Recycling,
*Agricultural runoff, Farm ponds, Computer models, Clays, Crop production,
Drainage, Costs, Economics.
The recycling agricultural runoff concept is the storage of excess water from
agricultural land and using this water for irrigation of the same land when
moisture supplies are low. Coincidentally, the system also recycles pesticides
and nutrients, keeping them out of other parts of the environment. The claypan
soils of Illinois appear to be best suited for water recycling when surface storage
is used. Sandy soils are best suited to interstitial water storage. A review
and analysis of literature on irrigation, drainage, reservoirs, pesticides,.and.
nutrients, as it pertains to a recycling system is presented. Nutrient and pesti-
cide recycling result in negligible cost or benefits to agricultural crops. There
was insufficient information to determine the economic benefit to the environment
of this recycling. A model was developed relating irrigation and drainage to crop
yield using intermediate variables of soil moisture and air temperature. The model
predicted that an acre-ft. of storage would be required per acre of irrigated
watershed. The model was not successful at predicting the increase in yield re-
sulting from irrigation and/or drainage. An example economic analysis reveals
that under present conditions recycling agricultural runoff is not economically
justifiable as a general practice in the claypan region of Illinois,
77:050-002
FACTORS AFFECTING NITRIFICATION,
Hockenbury, M.R., Daigger, G.T., and Grady, C.P.L., Jr.
Engineering-Science, Incorporated, Atlantic, Georgia,
Journal of the Environmental Engineering Division^ASCE, Vol. 103, No. EE1, p 9^19,
February 1977. 1 fig, 3 tab, 13 ref.
Descriptors: *Nitrification, *Bacteria, *0rganic matter, *Activated sludge,
Domestic wastes, Industrial wastes, Dissolved oxygen, Growth rates, Aeration, Hydro-
gen ion concentration, Waste water treatment.
Laboratory studies were conducted to investigate factors which affect nitrification.
These included the effect of heterotrophic bacteria and organic compounds on nitri-
fying bacteria, and the possible adverse effects created by material released in
waste water during treatment in a plug flow activated sludge aeration basin. Results
indicated no effects by actively metabolizing heterotrophic bacteria upon nitrate
production by autotrophic nitrifiers. Domestic sewage did not affect nitrate pro-
duction by nitrifying bacteria when inhibitory industrial wastes were absent. No
adverse effects from treatment in plug flow activated sludge aeration basins were
found when suitable pH and dissolved oxygen levels were maintained for autotrophic
nitrifiers. Heterotrophic bacteria released growth factors which slightly stimulated
autotrophic nitrifer activity. Many inhibitory compounds in tested sewage were
apparently degraded within the first half-hour of activated sludge treatment,
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77:050-003
GOAL PROGRAMMING MODEL FOR WATER QUALITY PLANNING,
Bishop, A.B., Narayanan, R. , Grenney, W.J., and Pugner, P.E.
Utah State University, Department of Civil and Environmental Engineering,
Logan, Utah.
Journal of the Environmental Engineering Division, Proceedings of the American
Society of Civil Engineers, Vol. 103, No, EE2, Proceedings Paper No. 12883,
p 293-306, April 1977. 4 fig, 7 tab, 9 ref.
Descriptors: *Waste water treatment, *Water quality control, *Multiple purpose,
*River basins, *Planning, Management, Optimization, Streams, Standards, Regions,
Costs, Mathematical models, Equations, Systems analysis.
The broad goals of the Federal Water Pollution Control Act Amendments (PL 92-500}
and the regional nature of water quality plans require that multiple objectives
be considered in planning. Goal programming is an extension of linear or integer
programming where the objective is to minimize the deviations from a set of goals,
subject to systems constraints. A goal programming model is applied to an example
river basin system where the planning goals are the quality levels of four consti-
tuents required or three desired beneficial water uses in five stream reaches, and
the budget availability in four municipal regions for financing wastewater treat-
ment. The model solution indicates the combination of treatment levels and costs
that minimizes deviations from user quality and budgetary goals for all stream
reaches. Values of deviation variables in the solution indicate the water quality
levels achieved. A comparison with the minimum cost solution for meeting stream
standards identifies the costs and tradeoffs of achieving higher user quality goals.
77:050-004
PHOSPHATE REMOVAL BY SANDS AND SOILS,
Tofflemire, T.J., and Chen, M.
New York State Department of Environmental Conservation, Research Unit, Albanyf New
York.
Ground Water, Vol. 15, No, 5, p 377-387, September-October, 1977. 6 fig, 13 tab,
31 ref.
Descriptors: *Unsaturated flow, *Laboratory tests, *Waste water disposal, *Recharge,
*Phosphates, Filtration, Soil characteristics, Infiltration, Soil profiles, Soils,
Sands, Waste disposal, Water quality, Filters, Soil filters, Adsorption,. Analytical
techniques.
Phosphate retention by soils is especially important for tile fields and rapid
infiltration systems near lakes where eutrophication is a problem. The use and
application of the phosphate adsorption isotherm test is estimate a soil's phos-
phate removal ability was discussed. It was found that in New York State, the
till soils had a greater phosphate retention ability than the outwashes, the more
acid soils had a greater phosphate retention than the more basic or calcareous soils.
The B horizon of many of the soils had a high phosphate capacity. However, this
is often neglected in rapid infiltration systems because the waste water is dis-
charged below the B horizon. The phosphate removal in column studies and field
studies in rapid infiltration systems was found to be greater than predicted by
the rapid isotherm test. Instermitten sand filters with 2 ft sand and underdrains
were found to have a limited ability to remove phosphate, A substantial portion of
slowly fixed phosphate is non-leachable by rain water. Methods to predict and design
for phosphate retention by sands and soils were described,
77:050-005
ATTENUATION OF WASTE WATER ELUTRIATED THROUGH GLACIAL OUTWASHf
Fetter, C.W., Jr.
Wisconsin University, Department of Geology, Oshkosh, Wisconsin,
Ground Water, Vol. 15, No. 5, p 365-371, September-October, 1977, 3 fig, 3 tab,
20 ref.
Descriptors: *Waste water treatment, *Tertiary treatment, *Laboratory tests,
*Glacial drift, Soil filters, Adsorption, Surfaces, Heavy metals, Ion exchange,
Recharge, Cadmium, Lead, Ammonia, Nitrification, Phosphorus.
216
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Secondarily treated waste water was added to plastic columns filled with calcareous
glacial outwash soil for a period of 10 weeks. More than 99% of the phosphorus
was retained in the upper 50 cm of the soil, primarily due to adsorption. Ammonia
nitrite, and organic nitrogen were nitrified biologically to nitrate nitrogen There
was no measurable mercury in the column effluent, and it was present in only 2 samples
of the waste water. About 30% of the cadmium was removed by ion exchange in the
soil columns. Lead was not removed, probably due to the prior exhaustion of the lead
exchange sites.
77:050-006
PHOSPHATE REMOVAL USING WASTE CALCIUM SULFATE,
Theis, T.L., and Fromm, G.A.
Notre Dame University, Department of Civil Engineering, Notre Dame, Indiana.
Journal of the Environmental Engineering Division, Vol. 103, No. 335, p 951-955,
4 fig, 8 ref, 1 append.
Descriptors: Phosphates, Calcium, Water pollution, Water quality, Water quality
control, Waste water, Waste water treatment.
Calcium sulfate (gypsum) is a common and inexpensive mineral which is among the
cheapest sources of soluble calcium ion available. Relatively pure calcium sulfate
is produced as a byproduct in several industries including chemical, pharmaceutical
(2), and, in the near future, it will also be produced by high sulfur coal-fired
utilities which must remove stack gas SO2 . Thus, on a local basis it may be ob-
tained at a markedly reduced cost, transportation being a major cost factor. This
study was undertaken to explore the possibility of employing gypsum as a supplemental
chemical for the removal of phosphate from wastewaters, and to determine under what
conditions it can be utilized in this manner.
77:05D-007
SALT REMOVAL EFFICIENCIES ON LAND DISPOSAL OF SWINE WASTE,
Grier, H.E., Gupta, G.C., and Tiwari, S.C,
Alcorn State University, Department of Animal Science, Lorman, Mississippi.
Journal of the Environmental Engineering Division, Vol. 103, No. EE4, p 551-556,
August 1977. 2 fig, 1 tab, 11 ref, 1 append.
Descriptors: Ammonia, Nitrates, Nutrients, Suspended solids, Waste disposal,
Waste water treatment. Effluents.
bwine waste aerobic lagoon effluent was sprinkled overland and the runoff water
was collected. Both the waste effluent and the runoff water were analyzed for
nitrate, ammonia, chloride, suspended solids, BOD,, and specific conductance. Re^
moval efficiency of nitrate dropped from 624 to 32% on prolonged disposal of swine
waste effluent, in six months. Data for suspended solids and specific conductance
support these results for, nitrate removal efficiency. Removal efficiencies for
ammonia and chloride were higher and showed a very small decrease with time, BOD
removal efficiency was 95% throughout the six-month period of the study. The
system showed signs of "overloading" for nitrate removal but not for BOD removal.
77:050-008
NITROGEN TRANSFORMATIONS IN LAND TREATMENT,
DiGiano, F.A., and Su, Y-S.
Massachusetts University, Department of Civil Engineering, Amherst, Massachusetts.
Journal of the Environmental Engineering Division, Vol. 103, No, EE6, p 1075-1087,
December 1977. 4 fig, 1 tab, 21 ref, 21 equ, 2 append.
Descriptors: Algae, Biological treatment, Lagoons, Land_reclamation, Model studies,
Nitrogen, Sewage treatment, Waste disposal, Water pollution.
The storage lagoon of a land treatment system functions as a dynamic biological
reactor in which algae and bacteria can transform input nitrogen. A quantitative
estimate of these nitrogen transformations is needed for proper design of the spray
irrigation component of land treatment. In this study, a simulation model was _
developed to predict the concentrations of inorganic and organic nitrogen and algae
in the lagoon throughout the winter storage and irrigation months; pilot plant data
217
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were used for verification. Both the predicted and observed results indicated
a large reduction in inorganic nitrogen caused by algal uptake during most of the
irrigation period. The model was then applied to achieve a better balance between
nitrogen supplied by the lagoon and crop demand throughout the growing season.
77:050-009
GROUND WATER POLLUTIONS. PART 2. POLLUTION FROM IRRIGATION AND FERTILIZATION,
CITATIONS FROM THE NATIONAL TECHNICAL INFORMATION SERVICE DATA BASE,
Lehmann, E.I.
National Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161.
National Technical Information Service, United States Department of Commerce,
NTIS/PS-76-0750, NTIS/PS-75/740, and NTIS/PS-75/072, February 1977, p 1-240.
Descriptors: Groundwater, Pollutants, Fertilization, Irrigation effects, Waste
water (pollution), Solid wastes, Nitrates, Phosphates, Abatement,. Water pollution,
Irrigation, Water conservation.
This bibliography contains abstracts of Federally-funded research covering all
aspects of groundwate'r pollution from irrigation and fertilization. The reports
include topics dealing with the pollution from sewage and waste water irrigation,
land spreading of sludges and solid wastes, nitrate and phosphate accumulation
in soils, pollution control and abatement planning, salt build-up from irrigation,
the use of tile drains in groundwater pollution control, and groundwater recharge
studies. (This updated bibliography contains 240 abstracts, 18 of which are new
entries to the previous edition,}
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SECTION XXII
WATER QUALITY MANAGEMENT AND PROTECTION
ULTIMATE DISPOSAL OF WASTES (GROUP 05E)
77:05E-001
STORAGE OF TREATED SEWAGE EFFLUENT AND STORM WATER IN A SALINE AQUIFER, PINELLAS
PENINSULA, FLORIDA.
Rosensheim, J.S., and Hickey, J,J.
Geological Survey, Water Resources Division, Tampa, Florida,
Ground Water, Vol. 15, No, 4, p 284-293, July-August, 1977. 5 fig, 3 tab, 11 ref.
Descriptors: *Waste disposal, *Injection wells, *Waste water disposal, Underground
storage, *Effluents, Saline water, Aquifers, Test wells, Aquifer characteristics,
Water quality control.
The Pinellas Peninsula, an area of 750 square kilometers (.290 square miles) in
coastal west-central Florida, is a small hydrogeologic replica of Florida. Most
of the Peninsula's water supply is imported from well fields as much as 65 kilometers
(40 miles) inland. Stresses on the hydrologic environment of the Peninsula and
on adjacent water bodies resulting from intensive water-resources development and
waste discharge, have resulted in marked interest in subsurface storage of waste
water (treated effluent and untreated storm water) and in future retrieval of the
stored water for nonpotable use. If subsurface storage is approved by regulatory
agencies, as much as 70 million gallons a day of waste water could be stored under-
ground within a few years, and more than 150 million gallons a day could be stored
in about 25 years. This storage would constitute a large resource of nearly
freshwater in the saline aquifers underlying about 520 square kilometers (200
square miles) of the Peninsula.
77:05E-002
SERVO CONTROLLED OPTIMIZATION OF NITRIFICATION-DENITRIFICATION OF WASTE WATER IN
SOIL,
Enfield, C.G.
Robert S. Kerr Environmental Research Lab, Ada, Oklahoma.
Journal of Environmental Quality, Vol. 6, No. 4, p 456-458,, October ^December, 1977.
5 fig, 1 tab, 9 ref.
Descriptors: *Infiltration, *Nitrification, *Denitrification, *Sewage treatment,
*Municipal wastes. Chemical reactions, Sludge, Soil amendments, Treatment facilities.
Electrical properties, Waste water disposal, Waste water treatment.
Studies were conducted to develop a servo control system which adjusts the rate of
waste water application to land to ensure nitrification-denitrification. Operation
of the control system is based on, the potentials of five platinum electrodes used
in conjunction with a Calomel reference electrode. A servo controller was used to
regulate application of municipal trickling filter final effluent to four gravelly
loam soil columns. The controller adjusted the frequency of waste water application
with respect to the Pt electrode potential 6 cm under the soil surface. The duration
of each application was regulated according to a target potential measured 30 cm
beneath the surface, optimizing denitrification. Three soil columns received 7,5
metric tons (carbon) of digested municipal sludge/ha in the upper 30 cm of the pro-
file. Waste water application was continuously allowed by the servo controller for
the column that contained no sludge. Essentially all 'total Kjeldahl nitrogen-
nitrogen was converted to nitrate-nitrogen in the upper 3 cm of this column. About
45% of the dissolved nitrogen disappeared in this column. Addition of sludge in-
creased apparent dentrification, so that total nitrogen removal exceeded 90«,
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SECTION XXVII
WATER QUALITY MANAGEMENT AND PROTECTION
WATER QUALITY CONTROL (GROUP O5G)
77:05G-001
EFFECT OF LEACHING FRACTION ON RIVER SALINITY,
Suarez, D.L., and Rhoades, J,D.
Agricultural Research Service, Salinity Laboratory, Riverside, California.
Journal of the Irrigation and Drainage Division, American Society of Civil
Engineers, Vol. 103, No. IR2, Proceedings Paper 13017, p 245-257, June 1977.
7 tab, 9 ref, 2 append.
Descriptors: *Drainage water, *Leaching, Irrigation engineering, *Salinity,
Management, Soil chemical properties, Calcium carbonate, Porosity, Rivers,
Water quality. Return flow, Drainage, Root zone, Saline soils, Gypsum, Model
studies.
The effects of 0.10 and 0.40 irrigation leaching fraction management on amount of
salt precipitated in the soil and river channel and compositions of drainage and
river water were calculated for each of the three river types routed through nine
successive hypothetical irrigated valleys. The calculations assume dissolution
of CaC03 (in the soil) and return of irrigation drainage waters. Rivers under-
saturated with CaC03 were slightly less saline under low versus .high leaching.
Rivers saturated with CaCOS were unaffected by irrigation management. Rivers
saturated with CaCOS and approaching saturation with gypsum experienced sub-
stantial reductions in salinity under low leaching compared to high leaching.
For CaC03-saturated rivers, a change from high to low leaching results in a root-
zone soil porosity reduction of 0,008% more per year, For rivers that result in
the precipitation of gypsum, soil porosity was reduced about 0.08% more per year
for low as compared to high leaching,
77:05G-002
REDUCTION OF 2, 4-D LOAD IN SURFACE RUNOFF DOWN A GRASSED WATERWAY,
Asmussen, L.E., White, A,W,, Jr,, Hauser, E.W,, and Sheridan, J,M,
Agricultural Research Service, Southern Region, Tifton, Georgia.
Journal of Environmental Quality, Vol. 6, No. 2, p 159-162, April-June, 1977,
4 fig, 3 tab, 8 ref.
Descriptors: *Herbicides, *Grassed waterways, *Water pollution, *Agricultural
chemicals, *Watershed management, Pesticides, Weed control, Surface
drainage, Agricultural watersheds, Surface runoff, Coastal plains, Pesticide
removal. Pollutants, Sediments, Surface runoff, Watersheds (basins).
The effectiveness of a grassed waterway in decreasing 2, 4-D ((2,4-dichlorophenoxy)
acetic acid)) content in surface runoff was investigated. Corn plots were treated
with 2, 4-D (0.56 kg/ha) and runoff produced by applying simulated rain was di-
rected through a 24.4-m-long grassed waterway. The 2, 4-D concentrations were
measured under wet and dry antecedent waterway and plot conditions. Reduction in
2, 4-D load in waterways results from water loss by infiltration, sediment loss,
and by attachment-absorption on vegetative and organic matter. Of the simulated
rainfall applied 1 day after application of 2, 4-D, 50% of the water ran off the
plots under dry antecedent soil conditions, and 78% ran off under wet conditions.
Infiltration reduced runoff flowing down the waterway an additional 25% under dry
conditions and 2% under wet conditions. Suspended sediment reduction in the
waterway was 98 and 94% of the total amount moving from the plot for the dry and
wet waterway conditions, respectively. The total loss Con sediment and in solu-
tion) of the applied 2,4-D from the plot in the dry and wet states was 2.5 and
10.3%, respectively.
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77:05G-003
WATER ALLOCATION AND PRICING FOR CONTROL OF IRRIGATION-RELATED SALINITY IN A
RIVER BASIN, O^-UNXII ILN A
Scherer, C.R.
California University, Department of Engineering Systems, Los Angeles California
Water Resources Research, Vol. 13, No. 2, p 225-238, April 1977. 10 fiq 5 tab '
49 ref. ' '
Descriptors: *Water allocation (policy), *Water quality control, *Salinity,
Irrigation, *Dynamic programming, *Economic efficiency, Optimization, Water
districts. Water rights, Pricing, Control, River basins, Downstream, Agriculture,
Decision making, Operations research, Legal aspects, Hydraulics, Equations, Water
yield.
The optimal allocation of water to sequential irrigators is considered with em-
phasis on downstream salinity damages caused by salt-concentrating mechanisms
inherent in irrigated agriculture. Outlined is a physical hydrosalinity model
that characterizes multi-irrigation district rivers and is used to develop a
dynamic programming framework for the efficient allocation of water among dis-
tricts. The focus is upon returns (maximization of net benefits) to farmers
as a function of quantity and quality of water diverted and upon developing
an operational model on which a viable water rights pricing scheme could be
based. The allocation is achieved using the dynamic programming framework with
decision variables of amount diverted, land irrigated, and amount of irrigation
canals lined. This framework is used to investigate a scheme whereby water is
purchased and held for downstream use solely as a dilutant, The basis is esta-
blished in principle for an operational water rights market where all purchasers
are financed by downstream beneficiaries. This framework would facilitate dis-
covery of reallocations that are Pareto superior to existing allocations and
computation of the individual purchase offer that must be made to each district
to compensate it for acreage withdrawn from irrigation under these new allocations
in order to reduce salinity impact on the downstream users. Four example solu-
tions are presented. Probably, better resolution of salinity management problems
will evolve if trade-offs and "efficiency frontiers" are correctly perceived.
77;05G-Q04
EFFECTS OF INCREASED FERTILIZER RATES ON NITROGEN CONTENT OF RUNOFF AND PERCOLATE
FROM MONOLITH LYSIMETERS,
Chichester, F.W.
Agricultural Research Service, Temple, Texas.
Journal of Environmental Quality, Vol. 6, No. 2, p 211-217, April-June, 1977,
4 fig, 6 tab, 9 ref.
Descriptors: *Nitrogen compounds, *Fertilizers, *Nitrates, *Leaching, *Agricultural
chemicals, Water quality, Nutrients, Pollutants, Water chemistry, Nitrogen, Water
pollution sources, Percolation, Runoff, Hydrology, Soil chemistry, Agricultural
runoff, Fertilization.
Nitrogen (N) fertilizer was applied to meadow and corn cropped lysimeters at rates
up to 322 and 672 kg/ha per year, respectively, to determine the effects on chemical
quality of surface water. Runoff and percolate samples collected from May 1971
through April 1975 were analyzed for inorganic and total N content. Results were
evaluated from crop and soil cover treatment differences and were compared with
data from a similar, earlier study on the same lysimeters in which very low rates
of N fertilizer were used. Nitrogen losses in runoff were greatest in the summer
when intense rainfall events occurred shortly after the date of fertilizer applica-
tion. Nitrogen loss by leaching was greatest during the winter when percolation
rates increased because of low evapotranspirational demand. Results of the study
demonstrated that improved fertilizer management, involving application rates in
balance with crop nutrient requirements, soil incorporation of fertilizer materials,
and adequate soil cover, will minimize runoff and leaching losses which reduce
fertilizer efficiency and a_dversely affect water quality.
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77:05G-005
NITROGEN AND WATER MANAGEMENT TO MINIMIZE RETURN-FLOW POLLUTION FROM POTATO
FIELDS OF THE COLUMBIA BASIN,
McNeal, B.L., Carlile, B.L., and Kunkel, R.
Washington State University, Department of Agronomy and Soils, Pullman, Washington.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 33-43, May 16-19, 1977.
7 tab, 7 ref.
Descriptors: Nitrogen, Fertilizers, Fertilization, Return flow, Water management
(applied), Potatoes, Columbia River, Crop production, Irrigation, Sprinkler
irrigation, Furrow irrigation.
Cooperative field studies have evaluated levels of dissolved soil N, and correspond-
ing crop yields for selected potato production practices in the Columbia Basin area
of Washington. High dissolved-N levels were found throughout the growing season in
well-managed potato fields. Such levels were decreased by decreased fertilization
rate, use of slow-release N fertilizers, or sprinklers-application of N fertilizers.
Careful water management during sprinkler irrigation proved capable of maintaining
dissolved-N within the root zone of subsequent crops by season*s end, even on very
sandy sites. Alternate-furrow irrigation also proved effective in "trapping"
much banded fertilizer N within the plant root zone on heavier-textured furrow-
irrigated soils. Periodic recovery of residual N by other crops in the rotation
is necessary to prevent eventual return flow contamination, however, Site-to^-site
sampling variability necessitated the use of composited soil samples, rather than
fixed-position soil solution extraction cups, for adequate monitoring of dissolved-
N levels in soils of the area. Neither dissolved soil N nor plant petiole NO3-N
proved to be reliable predictors of crop N needs at the high residual soil N levels
commonly found in recropped potato fields of the Columbia Basin.
77:05G-006
MODELING SALINITY OF IRRIGATION RETURN FLOW WHERE SOURCES AND SINKS ARE PRESENT,
Hanks, R.J., Willardson, L,S,, and Melamed, D.
Utah State University, College of Agriculture, Department of Soil Science and
Biometeorology, Logan Utah,
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 99-107, May 16-19, 1977,
10 fig, 2 tab, 9 ref, 4 equ.
Descriptors: Model studies, Simulation analysis.
Managing irrigation return flow when salinity sources and sinks are present presents
many complex difficulties. Models developed to include the source sink term in an
empirical way show that wide variations in irrigation quality and quantity will have
little influence on return flow for many years where the source-sink term is im*-
portant. The quantity of salt in return flow is primarily determined by water
flow because the soil solution concentration changes very slowly. Where a water
table is present, successful irrigation might be practiced with no return flow
for some conditions. Even where no source-sink term is considered, model predic-
tions indicate irrigation management with no return flow for several years is
possible with little reduction in yield, The influence of irrigation system
uniformity is shown to be significant over several years time. Thus, it is evi^
dent that many possibilities for return flow management exist but the long term
effects should not be overlooked,
77:05G-007
COMBINING AGRICULTURAL IMPROVEMENTS AND DESALTING OF RETURN FLOWS TO OPTIMIZE
LOCAL SALINITY CONTROL POLICIES,
Walker, W.R.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 203-213, May 16-19, 1977.
7 fig, 9 ref, 22 equ.
Descriptors: Model studies, Mathematical simulation, Desalination, Irrigation,
Colorado, Seepage.
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Mathematical simulations of the cost-effectiveness relationship for various
agricultural and desalination alternatives for controlling salinity in irrigation
return flows are being developed. The question of respective feasibility for each
type of control is determined through minimizing the total costs, thereby optimally
selecting the best measures to implement. To demonstrate the concept desalting
and canal linings were compared for the Grand Valley in western Colorado Results
indicate that desalting exhibits superior feasibility to linings of canals where
seepage rates are low. In general, desalting will exhibit its best feasibility
when applied to large-scale applications and when salt pickup rates stemming from
irrigation return flows are small.
77:05G-008
PRACTICAL APPLICATIONS OF IRRIGATION RETURN FLOW QUALITY MODELS TO LARGE ACREAGES,
Shaffer, M.J., and Ribbens, R.W.
United States Bureau of Reclamation, Engineering and Research Center, Denver,
Colorado.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 217-223, May 16-19, 1977.
6 fig, 1 tab, 12 ref.
Descriptors; Model studies, Simulation analysis, Water quality, Water quality
control. Irrigation, Return flow.
Numerous return flow quality simulation models have been developed in recent years.
Practical use of these tools on large irrigation projects is discussed in terms
of study objectives, data requirements and availability, model detail and sensiti-
vity, inherent limitations, and reliability and interpretation of results. The
modeling efforts of the Bureau of Reclamation and other institutionsare used to
illustrate the utility and practicability of these new tools. Potential and
present model users should gain valuable insight into the benefits and pitfalls
of return flow quality modeling.
77:056-009
MODELING THE IRRIGATION RETURN FLOW SYSTEMCURRENT CAPABILITIES AND FUTURE NEEDS,
Walker, W.R,
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 261-265, May 16-19. 1977.
Descriptors: Model studies. Simulation analysis, Water quality, Mathematical
studies.
A large number of mathematical models have been developed and tested for simulation
of irrigation return flow systems. The strengths and weaknesses of the technology
have been examined as part of two recent studies by the author. This paper dis-
cusses what seems to be some of the more critical problems in using these models,
the relative strengths of those existing, and important research and development
needs for maximizing their utilization in the future.
77:05G-010
HOW THE NPDES PROGRAM WILL DEFINE PRESENT WATER QUALITY CONDITIONS,
Merrill, G.
Central Valley Regional Water Quality Control Board, Sacramento, California,
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 289-291, May 16-19, 13//.
3 tab.
Descriptors: Surface irrigation, Return flow, California, Suspended solids,
Irrigation, Water quality control.
Monitoring of surface irrigation supplies and surface return flows is being carried
on through the NPDES permit program under Public Law 92-500. This program encom-
passes approximately 1.3 million acres of land in the San Joaquin Valley f
California alone. The EC and suspended solids of the ^igation returns frequently
exceed basin water quality control plan objectives (standards) adopted in 1971 by
the Central Valley Board for the receiving water.
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77:05G-011
THE SULPHUR CREEK PILOT PROJECT: A PRACTICAL APPROACH TO CONTROL OF POLLUTANTS
LEAVING IRRIGATED FARMLANDS,
Spencer, J-, Horton, M., and Gleaton, J.
State of Washington, Department of Ecology, Olympia, Washington.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 307-319, May 16-19, 1977.
2 fig, 1 tab.
Descriptors: Washington, Return flow, Water quality, Fertilizers, Pesticides,
Crop production, Irrigation, Economics.
The Sulphur Creek project grew out of the momentum and confusion resulting from
attempts to apply a National Pollution Discharge Elimination System (NPDES) permit
to irrigation return flows. The result has been a project containing what appeared
to be compatible and, for the most part, admirable objectives^soil and water con-
servation, improved water quality, improved fertilizers and pesticides application,
improved crop production, and local control. Along with education and technical
assistance for the individual farmer, this unique program is structured to provide
local control to decisions affecting the farmer. The Best Management Practices
concept assumes that informed decisions and improved management will generally
provide improved crop production, conservation of soil resources, and cleaner
water. The project is currently just over one year old. Details of the technical
success of the project will not be available for some time. Unlike most types of
industry covered by the NPDES permits, irrigation return flow improvement represents
complex hurdles which have to be overcome by facing the realities of technology,
politics, economics, and social patterns,
77:050-012
THE "208" PLANNING EFFORT FOR IRRIGATED AGRICULTURE IN THE STATE OF WASHINGTON,
Horton, M., and Spencer, J.
State of Washington, Department of Ecology, Olympia, Washington.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 321-323, May 16-19, 1977.
1 fig.
Descriptors: Irrigation, Irrigation effects, Washington, Agriculture, Water
quality, Economics.
The Department of Ecology is responsible for developing a "208" Plan for irrigated
agriculture in the State of Washington, It is anticipated that Best Management
Practices (BMP) will be utilized by individuals to come into compliance with a
state-wide regulatory program (possibly NPDES). Water quality committees formed
through local conservation districts, with representatives from all interested
groups, will develop BMP based on the following criteria; (1) economic feasibility;
(2) local acceptability; and (3) water quality improvement.
77:05G-013
EVALUATING APPROPRIATE TECHNOLOGIES FOR SALINITY CONTROL IN GRAND VALLEY,
Evans, R.G., Walker, W.R., Smith, S.W,, and Skogerboe, G.V.
Colorado State University, Department of Agriculture and Chemical Engineering,
Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 375-384, May 16-19, 1977.
3 fig, 2 tab, 3 ref.
Descriptors: Technology, Irrigation practices, Irrigation systems. Canal linings,
Colorado, Colorado River, Salinity, Irrigation, Economics,
A summary of the results of applied research on salinity control of irrigation
return flows in the Grand Valley of Colorado is presented for the period of 1969 to
1976. Salinity and economic impacts are described for the Grand Valley Salinity
Control Demonstration Area which contains approximately 1600 hectares and involves
most of the local irrigation entities in the valley. During the eight years of the
demonstration project, 12.2 km of canals were lined, 26.54 km of laterals were
lined, 16.4 km of drainage tile was installed, a wide variety of on-farm improvements
were constructed, and an irrigation scheduling program was implemented. The total
value of the constructed improvements in the demonstration area was almost $750,000.
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77:05G-014
DEVELOPMENT OF BEST MANAGEMENT PRACTICES FOR SALINITY CONTROL IN GRAND VALLEY
Walker, W.R., Skogerboe, G.V., and Evans, R.G. '
Colorado State University, Department of Agriculture and Chemical Engineering,
Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 385-393, May 16-19, 1977.
5 fig, 7 ref, 16 equ.
Descriptors: Canal linings, Water quality, Water quality control. Desalination,
Colorado River, Salinity, Colorado.
Cost-effectiveness functions for various on-farm, conveyance, and desalting salinity
control alternatives were developed for the Grand Valley of western Colorado.
These functions were then optimized to determine the best management practices on
a valley-wide scale. The results indicate the relative importance of lateral
linings and on-farm improvements over either canal lining or desalting. Generalized
curves are presented for application of this analysis to other similar areas where
less information is available.
77:05G-015
WATER QUALITY: AN OVERVIEW,
Mostertman, L.J.
Technische Hogeschool, International Course in Hydraulics and Sanitary Engineering,
Delft, The Netherlands.
Agro-Ecosystems, Vol, 3, No. 3, p 239-251, June 1977. 8 ref.
Descriptors: Water resources, Pollution, Water pollution, Water chemistry, Nutrients,
Salinity, Thermal pollution. Water resources.
The water resources of the world are described in relation to: La) evaluation of
present and future needs, (b) collection of data, (c) biological pollution, (d)
drinking water supply, (e) pollution by chemicals, (f) pollution by excessive
nutrients, (g) salinity and alkalinity, (h) thermal pollution, (i) organic waste
treatment and disposal, and (j) need for a systems approach. The possibilities of
constructive action, particularly on an international front, are discussed.
77:05G-016
REDUCING WATER QUALITY DEGRADATION THROUGH MINIMIZED LEACHING MANAGEMENT,
Rhoades, D.L., and Suarez, D,L.
United States Department of Agriculture, Agricultural Research Service, United
States Salinity Laboratory, Post Office Box 672, Riverside, California 92502.
Agricultural Water Management, Vol. 1, No. 2, p 127-142, September 1977. 10 tab,
15 ref, 3 equ.
Descriptors: Water quality, Water quality control, Leaching, Water resources,
Salinity, Saline soils, Agriculture,
The U.S.A. has adopted a policy of enhancing water quality and of conserving
natural resources. The concept of minimized leaching has been advanced to help
meet these goals by reducing salinity pollution from irrigated agriculture. It
has received considerable attention by those concerned with management of water
resources and is promoted by some as a generally applicable method for minimizing
salinity pollution. This paper reviews the basis of the concept and identifies
the conditions under which minimized leaching will and will not enhance water
quality.
DISPOSAL OF SALT WATER DURING WELL CONSTRUCTION, PROBLEMS AND SOLUTIONS,
Pitt, W.A.J., Jr., Meyer, F.W,, and Hull, J.E.
Geological Survey, Water Resources Division, Miami, Florida. , --v.
Ground Water, Vol. 15, No. 4, p 276-283, July-August, 1977. 6 fig, 1 tab.
Descriptors- "Injection wells, 'Drilling, *Water pollution sources, *Saline water,
Florida Aquifers Drilling fluids, Sewage disposal, Monitoring, Pumping, Ground-
225
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necent interest in disposal of treated sewage effluent by deep-well injection into
saline aquifers has increased the need for proper disposal of salt water as more
wells are drilled annually. Three cases of contamination of an unconfined aquifer
in Florida by salt water spilled or discharged from wells trapping the underlying
saline aquifer are examined in this study. In two cases, near Miami, contamination
resulted from disposal of salt water into unlined surface bits during injection
well construction. At the third site near West Palm Beach, minor contamination
was caused by accidental spills during construction. Precautions taken at the
latter site included the use of a brine injection well for disposal of saline
water and a closed circulation drilling system to minimize spillage. A concurrent
monitoring program facilitated early detection of salt spill effects, thus, mapping
of the contaminant and restoration efforts were effective and relatively inexpensive.
Suggestions for further increasing the safety of drilling into saline aquifers
include the construction of impermeable drilling pads with gutters and employing
special procedures for handling drilling muds.
77:056-018
REGIONAL MANAGEMENT OF URBAN AND AGRICULTURAL POLLUTION,
Lashkari, R.S., Hwang, C.L,. and Fan, L.T.
Windsor University.- Ontario, Canada.
Journal of the Water Pollution Control Federation, Vol. 49, No. 8, p 1877-1888,
August 1977. 6 fig, 6 tab, 13 ref.
Descriptors: *Water quality control, *Salinity, *Biochemical oxygen demand,
*Economic efficiency, *Water policy, *0ptimization, *Drainage area, Costs, Con-
straints, Water demand, Agriculture, Utah, Standards, Desalination plants,
Irrigation, Equations, Mathematical models. Systems analysis.
Presented is an approach to water quality management in areas where a variety of
urban and agricultural pollutants are discharged into a body of water. The Utah
Lake drainage area is considered in which the urban and agricultural return flow
from four districts of the Utah Valley are discharged into the Lake. A model of
salinity and biochemical oxygen control is used which coordinates the pollution
control activities of the urban and agricultural sectors in each district. The
model consists of a wastewater treatment system and a desalting plant in the urban
sector, and a. combination of structural and practice improvements in the irrigation
system of the agricultural sector. The objective is to minimize the costs of main-
taining certain biochemical oxygen demand and salt reduction standards in the
districts' aggregate effluents to the Lake under two assumptions: that each dis-
trict is to maintain the standards independently, and that the salinity-biochemical
oxygen demand control efforts of the individual districts are regionally coordinated.
The results indicate that savings can be achieved through regional coordination of
pollution control efforts.
77:05G-019
DETAILED RETURN FLOW SALINITY AND NUTRIENT SIMULATION MODEL,
Shaffer, M.J.
Bureau of Reclamation, Denver, Colorado.
Proceedings of the International Salinity Conference, Texas Tech University,
Lubbock, Texas, August 16-20, 1976, p 127-141. 8 fig, 18 ref,
Descriptors: *Simulation analysis, *Nutrlents, *Return flow, *Salinity, Model
studies, Drainage, Nitrogen, Water quality, Lysimeters, Irrigation effects,
A computer model allows the simultaneous consideration of many complex chemical
and physical processes in the unsaturated and saturated zones. The model simulates
one-dimensional unsaturated flow and two-dimensional saturated flow (.to tile drains),
as well as chemical reactions and transport processes involving the major cations
and anions, and nitrogenous species. The program also includes crop uptake of
water and nutrients. A numerical integration technique is utilized to solve the
appropriate differential equations, and generate transient predictions throughout
the soil-aquifer system, and at the drains. Utilization of a master site technique
allows application of the model to predict irrigation return flow quality and
quantity from large irrigated areas involving thousands of acres. Verification has
been accomplished on large acreages as well as field plots, lysimeters, and laboratory
columns. The model has a well-documented user's manual and has been applied to
several large irrigation projects.
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77:05G-020
NATIONAL WATER QUALITY GOALS AND IRRIGATED AGRICULTURE,
Johnston, W.R.
Westlands Water District, Fresno, California.
Journal of the Irrigation and Drainage Division, America Society of Civil
Engineers, Vol. 103, No. IR2, p 109-114, June 1977. 10 ref.
Descriptors: Irrigation, Water quality, Water, Return flow, Irrigation effects
Agriculture, Irrigation water, Crop production.
In 1972, the United States government, reflecting the concern of people everywhere
over the pollution of this country's water resources, passed the Federal Water
Pollution Control Act Amendments of 1972. This law created certain national water
quality goals and has had great impact on municipal and industrial activities
that relate to the water systems of the United States.
77:05G-021
PL 92-500 V. POLLUTION BY IRRIGATION RETURN FLOW,
Blackman, W.C., Jr., Wills, C.G., and Celnicker, A.C.
National Enforcement Investigations Center, Denver, Colorado.
Journal of the Irrigation and Drainage Division, Proceedings of ASCE, Vol. 103,
No. 2, p 207-220, June 1977. 3 fig, 14 ref.
Descriptors: *Federal Water Pollution Control Act, *Federal Reclamation Law,
Irrigation districts, Irrigation return flow, Irrigation practices, Pollution
abatement, Water pollution control, Irrigation, Permits, Regulation, Administrative
agencies, Governmental interrelations, Effluent limitation.
This paper summarizes the problems of applying the municipal/industrial waste
treatment oriented permit approach of the National Pollutant Discharge Elimination
System to the control of irrigation return flow as embodied in the Federal Water
Pollution Control Act Amendments of 1972. It is held that there must be acceptance
and implementation of optimum application of irrigation water, even though optimum
application may involve use of less than the prior appropriated water right. In
the promulgation of regulations by the Environmental Protection Agency, the EPA
should recognize that regional and delegated state administrators must have
flexibility to designate permittees on the basis of logic. Since the Bureau of
Reclamation plans, administers and operates many newly established irrigation
projects, it is uniquely qualified to provide leadership and guidance toward opti-
mum practices within project areas. In established irrigation districts and major
irrigated areas, EPA should initiate a program of grants and contracts to enable
optimum operation of plots representative of each area. Such recommendations
and others will require modified viewpoints of irrigators, legislators, regulatory
agencies and others.
77:056-022
PROCEEDINGS OF NATIONAL CONFERENCE: IRRIGATION RETURN FLOW QUALITY MANAGEMENT,
Law, J.P., and Skogerboe, G.V,
Conference sponsored by the Environmental Protection Agency and Colorado State
University.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 1-451, May 16^19, 1977,
193 fig, 136 tab, 310 ref, 106 equ, 1 append.
Descriptors: Irrigation, Irrigation systems, Irrigation practices, Crop production,
Crop response, Return flow, Water quality control, Model studies, Agriculture,
Technology, Salinity, Fertilization, Groundwater, Runoff, Erosion, Sedimentation,
Water resources, Water conservation, Irrigation efficiency, Water law, Water
management (applied), Pollutants, Pollution abatement, Pollutant identification.
The results of numerous research projects and investigations are presented which
focus upon defining appropriate technologies for alleviating water quality problems
from irrigated agriculture; most of these technologies involve improved_water
management practices. In addition, case studies are presented for key irrigated
areas in the United States which provide necessary insights and experiences_as to
how technologies might be most effectively implemented. The primary objectives
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of the conference were: (1) to present the results of the irrigation return
flow research and development program of the United States Environmental
Protection Agency; (2) to interpret the research results into an interdisciplinary
approach for solving problems of irrigation return flow quality management; and
(3) to provide a forum for presenting and discussing the alternatives for implementing
irrigation return flow quality control.
77:05G-023
CONTROL OF NONPOINT WATER POLLUTION FROM AGRICULTURE: SOME CONCEPTS ,
Frere, M.H., Woolhiser, D.A., Caro, J.H., Stewart, B.A., and Wischmeier, W.H.
Agricultural Research Service, Southern Great Plains Watershed Research Center,
Chickasha, Oklahoma,
Journal of Soil and Water Conservation, Vol. 32, No. 6, November-December, 1977,
p 260-264. 6 fig, 1 tab, 13 ref.
Descriptors: *Water pollution control, *Erosion, *Fertilizers, *Pesticides,
*Farm management, *Nonpoint source pollution, Federal water pollution control
act, Agricultural chemicals, Watersheds, River basins, Runoff, Farm wastes,
Nutrients, Pollution taxes, Education, Conservation, Alternative practices,
Incentives.
Federal and State laws require that methods be developed for evaluating nonpoint
pollution problems and for recommending control practices. Since the major
responsibility for control lies with organizations covering large areas, such
as river basins or states, the task is difficult at best. Control methods can
be classified into two groups: (1) methods applicable to large areas, and (2)
farming practices that are site-specific because of climate, topography,
economics, etc. Some advantages and disadvantages of education, incentives,
taxation, and legal penalties for broad areas are discussed.' The use of flow
charts for erosion, nutrient, and pesticide problems are briefly discussed.
The charts should be useful in selecting farming practices that reduce nonpoint
pollution and in evaluating their consequences.
77:05G-024
TILLAGE SYSTEM EFFECTS ON RUNOFF WATER QUALITY: PESTICIDES,
Baker, J.L., and Johnson, H.P.
Iowa State University, Department of Agricultural Engineering, Ames, Iowa 50011.
Presented at the 1977 Winter Meeting, American Society of Agricultural Engineers,
December 13-16, 1977, Palmer House, Chicago, Illinois, p 1-14. 2 fig, 4 tab,
17 ref.
Descriptors: Pesticides, Runoff, Sedimentation, Corn, Erosion, Soil erosion,
Sediments, Water quality.
Pesticide runoff losses in sediment and water were measured for six small water-
sheds planted to continuous corn by three tillage systems: conventional, till-
plant, and ridge-plant. Decreased runoff and erosion for the till-plant and ridge-
plant systems resulted in decreased pesticide losses; however, pesticide concen-
trations in sediment and/or water were sometimes higher (relative to conventional),
77:05G-025
AN INTRODUCTION TO FOUR OVERVIEWS: ARID AND SEMI-ARID LANDS; SOIL LOSS; TROPICAL
FORESTS AND WOODLANDS; WATER QUALITY,
Tolba, M.K.
The United Nations Environment Program.
Agro-Ecosystems, Vol. 3, No. 3, p 183-184, June 1977.
Descriptors: Erosion, Water quality, Water, Watersheds (basins) ,. Climates,
Arid lands, Arid climates.
One of the major tasks assigned by the United Nations General Assembly to the
Governing Council of the United Nations Environment Program, in the aftermath
of recommendations made at the United Nations Conference on the Human Environment
convened at Stockholm in 1972, was to "keep under review the world environmental
situation in order to ensure that emerging environmental problems of wide
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international significance receive appropriate and adequate consideration " To
assist in carrying out this task, the Executive Director was requested by'the
Governing Council of UNEP, at its second session in 1974, to prepare each year
reviews of one or more of the priority subject areas of the Environment Program
in addition to preparing an annual State of the Environment Report which sum-
marizes the most important and the major emerging issues that affected the
environment during the preceding year.
77:05G-026
THE CONTROL OF NITRATE AS A WATER POLLUTANT,
Swoboda, A.R.
Texas A and M University, Texas Agricultural Experiment Station, College Station
Texas 77843. '
Publication No. EPA-600/2-77-158, August 1977. 141 p, 16 fig, 55 tab, 14 ref,
3 append.
Descriptors: Nitrates, Leaching, Soils, Crop production. Fertilizers, Fertiliza-
tion, Nutrients, Lysimeters.
This study was based on the premise that the most logical approach to reducing
nitrate leaching in soils was to limit the amount of nitrate in the soil solution
at any one time. Methods of limiting the concentration of nitrate in the soil
solution while maintaining an adequate supply of available nitrogen for plant
growth are reported. Timing of nitrogen application was found to be a very ef-
fective means of reducing nitrate leaching. When nitrogen was applied in the
fall, as much as 3-fold more nitrate was found to have leached below 60 cm in the
soil by June as compared to applications made in March. A nitrification inhibitor,
N-Serve, was found to be very effective in reducing the amount of nitrate leached.
Slow release sulfur coated ureas and treatment of nitrogen fertilizers with N-
Serve were found to be effective means of reducing leaching losses of nitrate
when fertilizers were applied in the fall or winter.
77:05G-027
PREDICTION OF MINERAL QUALITY OF IRRIGATION RETURN FLOW: VOLUME I. SUMMARY
REPORT AND VERIFICATION,
Bureau of Reclamation, Engineering and Research Center, Denver, Colorado 80225.
Publication No. EPA-600/2-77-179a, August 1977. 59 p, 5 fig, 2 tab, 6 ref.
Descriptors: Water quality, Return flow, Irrigation, Irrigation effects, Model
studies, Salinity, Dissolved solids. Simulation analysis, Groundwater, Hydrology.
This volume of the report outlines the purpose and scope of the return flow research
and specifically explains the capabilities of the conjunctive use model for pre-
dicting the mineral quality of irrigation return flow. The purpose of the re-
search was to develop a conjunctive use model which would (.1) predict the salinity
contribution from new irrigation projects and (2) predict the change in return
flow salinity that would'result from operational changes on exisiting projects.
The model developed and described herein describes the chemical quality in terms
of eight ionic constituents and total dissolved solids, A nodal concept has been
used to facilitate subdividing the project area along physical or hydrologic
boundaries as desired. The study may be limited to 1 or as many as 20 nodes,
VOLUME II. VERNAL
77:05G-028
PREDICTION OF MINERAL QUALITY OF IRRIGATION RETURN FLOW:
FIELD STUDY,
Bureau of Reclamation, Engineering and Research Center, Denver, Colorado 80225.
Publication No. EPA-600/2-77-179b, August 1977. 106 p, 45 fig, 9 tab, 1 append.
Descriptors: Utah, Groundwater, Water quality, Irrigation, Irrigation water,
Return flow, Crop production, Soil chemistry, Simulation analysis.
This volume of the report 'details the field investigations conducted to develop
and validate the "Simulation Model of Conjunctive Use and Water Quality for a
River System or Basin" as given in Volume III of this report, The studies were
conducted in Ashley Valley.- near Vernal, Utah. The investigations included: the
quantity and quality of groundwater, irrigation water, and return flows; crop
inventory and consumptive use; soil chemistry; and hydrological units to define
nodes.
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77:05G-029
PREDICTION OF MINERAL DUALITY OF IRRIGATION RETURN FLOW: VOLUME III. SIMULATION
MODEL OF CONJUNCTIVE USE AND WATER QUALITY FOR A RIVER SYSTEM OR BASIN,
Bureau of Reclamation, Engineering and Research Center, Denver, Colorado 80225.
Publication No. EPA-600/2-77-179c, August 1977. 285 p, 43 fig, 18 tab, 1 append.
Descriptors: Computer programs, Simulation analysis, Model studies, Irrigation,
Irrigation effects, Return flow, Water quality.
This volume of the report documents the development of a digital computer coded
simulation model to predict the effect of irrigation of agricultural lands on the
resulting irrigation return flow quality. The model is capable of simulating
conjunctive uses of water, however, validation for this purpose was not performed.
The model developed in this volume is much less rigorous than that presented in
Volume V, however, it can be used to provide an assessment of water quality trends
due to irrigation at much less cost than the detailed model. A user's manual
is included in the report.
77:05G-030
PREDICTION OF MINERAL QUALITY OF IRRIGATION RETURN FLOW: VOLUME IV. DATA ANALYSIS
UTILITY PROGRAMS,
Bureau of Reclamation, Engineering and Research Center, Denver, Colorado 80225.
Publication No. EPA-600/2-77-179d, August 1977. 222 p, 1 ref.
Descriptors: Return flow, Irrigation, Irrigation effects. Water quality, Computer
programs, Model studies, Simulation analysis.
This volume of the report contains a description of the data analysis subroutines
developed to support the modeling effort described in Volume III. The subroutines
were used to evaluate and condition data used in the conjunctive use model. The
subroutines include (1) regression analysis, (2) Gaussian probability function,
(3) Beta distribution, and (4) Pearson's incomplete gamma function. For each of
these subroutines, a brief theory is given plus a program listing and sample
problem.
77:05G-031
CALLAHAN RESERVOIR: I. SEDIMENT AND NUTRIENT TRAP EFFICIENCY,
Rausch, D.L., and Schreiber, J.D.
Agricultural Research Service, North Central Watershed Research Center, Columbia,
Missouri.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 2,
p 281-284, 290, March-April, 1977. 2 fig, 3 tab, 10 ref.
Descriptors: *Reservoirs, *Sediments, *Nutrients, *Missouri, *Trap efficiency,
Sedimentation, Water pollution, Phosphorus, Nitrogen, Runoff, Inflow, Discharge
(water), Path of pollutants, Lakes.
Small reservoirs remove and trap significant amounts of sediment and nutrients
from storm runoff. Callahan Reservoir, a small floods-detention reservoir in
central Missouri, which permanently stores 1 cm of runoff from its 1,440-ha
drainage area, trapped an average of 87% of the incoming sediment, 72% of the
total phosphorus (P), and 30% of the inorganic nitrogen ON) in 1973. Sediment
efficiency and P trap efficiency in the reservoir were both related to the in*-
coming sediment particle-size; however, only sediment trap efficiency was related
to detention time. The annual amount of N03 trapped seemed related to annual
runoff volume. For 1973, the soluble nutrients, total soluble P, and N03 were
trapped at similar rates, 32% and 34%, respectively. More NH4, dissolved organic
P and dissolved hydrolyzable P were found in outflow than in inflow. The in-
creases, which are less than 2% of the nutrient budget, may be attributed to
biological activity in the reservoir.
77:O5G-032
CALLAHAN RESERVOIR: II. INFLOW AND OUTFLOW SUSPENDED SEDIMENT PHOSPHORUS
RELATIONSHIPS,
Schreiber, J.D., Rausch, D.L., and McDowell, L.L.
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United States Department of Agriculture Sedimentation Laboratory, Agricultural
Research Service, Oxford, Mississippi.
Transactions of the American Society of Agricultural Engineers. Special Edition
Vol. 20SW, p 285-289, April 20, 1977, 5 fig, 4 tab, 23 ref, 1 equ.
Descriptors: Missouri, Sediments, Flood control, Reservoirs, Downstream,
Agricultural watersheds, Phosphorus.
The inflow and outflow of Callahan Reservoir, located in an agricultural area
near Columbia, Missouri, was studied for 1 year to understand the sediment and
solution phosphorus (P) relationships. The solution phase was analyzed for
dissolved organic, hydrolyzable, and ortho-P and the sediment was analyzed for
total, inorganic, and organic P. The discharge weighted mean solution phase
concentration of dissolved organic, hydrolyzable, and ortho-P for the inflow
was 0.008, 0.002 and 0.059, mg/1, respectively, as compared with 0.011, 0.005,
and 0.021 mg/1 for the outflow. The outflow sediment had a larger concentration
(mu g/g) of total, inorganic, and organic P than did the inflow sediment.
However, because of sediment deposition within the reservoir, there was a 4-
fold decrease in outflow suspended sediment P volume concentrations (.mg/1) .
Isotopic dilution techniques with 32P were used to estimate the portion of
sediment-P31 in equilibrium with solution-P31, The quantities of isotopically
exchangeable sediment-PSl in the inflow and outflow sediments were 30 and 41
mu g/g, respectively.
77:05G-033
CALLAHAN RESERVOIR: III. BOTTOM SEDIMENT-WATER-PHOSPHORUS RELATIONSHIPS,
Olness, A., and Rausch, D.
Agricultural Research Service, Water Quality Management Laboratory, Durant,
Oklahoma.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. 2,
p 291-297, 300, March-April, 1977. 6 fig, 3 tab, 38 ref.
Descriptors: *Reservoirs, *Bottom sediments, *Water quality, Sediments, Chemical
properties. Chemical analysis, Physical properties, Cores, Sampling, Phosphorus,
Nutrients, Water chemistry, Lakes, Limnology.
Sediment core samples obtained from a 164,000 cu m reservoir in central Missouri
showed highly significant correlations between sediment clay content and phosphorus
concentrations. Both sediment clay content and phosphorus concentrations increased
with distance from the reservoir inlet. No strong correlations between phosphorus
concentration and sediment depth were observed. Phosphorus concentrations varied
widely between and within core profiles ranging from less than 100 ppm to more
than 1000 ppm and from less than 200 ppb to more than 3000 ppb for total phosphorus
and total soluble phosphorus, respectively. The mean total phosphorus concentration
in the reservoir water was 108 ppb. About 25% and 10% of the total suspended
phosphorus was soluble phosphorus and soluble reactive phosphorus, respectively.
The reservoir sediments seemed to serve as a phosphorus sink either through
chemical adsorption or planktonic and mineral sedimentation,
77:05G-034
SOIL-SALT INTERACTIONS IN RELATION TO SALT CONTROL,
Biggar, J.W., and Tanji, K,K.
Land, Air and Water Resources Department, University of California, Davis,
California.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 68-75, February 20, 1977. 1 tab, 50 ref, 9 equ.
Descriptors: Root zones, Return flow, Salts, Cation exchange, Ion exchange, Water
management (applied), Crop production, Salt tolerance, Soils.
An appraisal is made on the difficulties of predicting and evaluating mass
emission of salts in irrigation return flows. The more important physicochemical
processes that occur in the root zone are identified and the complexity and
state-of-the-art knowledge of them is discussed.
231
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77 :05G-035
RECLAIMING PARTIALLY CLOGGED TRICKLE EMITTERS,
Nakayama, F.S., Bucks, D.A., and French, 0,F.
United States Water Conservation Laboratory, Agricultural Research Service, United
States Department of Agriculture, Phoenix, Arizona.
Transactions of the American Society of Agricultural Engineers, Special Edition,
Vol. 20SW, p 278-280, April 20, 1977. 1 fig, 1 tab, 9 ref.
Descriptors: Irrigation systems, Trickle filters, Clogging, Flow rate, Laboratory
tests, Injection.
A trickle emitter system, which had become partially clogged after two years of
operation even with extensive water filtration, was reclaimed successfully by
treating the entire system with concentrated hypochlorite and acid solutions.
Chemical cost per emitter was less than replacement cost for the emitter and
supply tubing. Maintenance treatment with low levels of hypochlorite and acid
prevented recurrence of emitter plugging,
77:05G-036
SOIL-ASPHALT MIXTURE FOR CANAL SEEPAGE CONTROL: LABORATORY STUDY,
Sommerfeldt, T.G.
Research Station, Agriculture Canada, Lethbridge, Alberta, TIJ 4B1, Canada.
Canadian Agricultural Engineering, Vol. 19, No. 2, p 111-115, December 1977.
Descriptors: Laboratory tests. Seepage control, Seepage, Asphalt, Soils, Irriga-
tion canals, Model studies, Salinity, Linings.
A material for lining irrigation canals composed of soil, anionic asphalt emulsion,
Wyoming bentonite, an enzymatic wetting agent, and water was developed in the
laboratory. Discs of the material were tested for seepage control, and resistance
to erosion, weathering, freezing, and thawing. A ditch model was subjected to
a continuous stream of water for 30 days. The material was satisfactory under
laboratory conditions. It had some flexibility and, when wet, was soft and
spongy, similar to gum rubber. This flexibility would be advantageous for
canals where shifting of the base or frost-heaving is a problem. But, because of
its softness, damage from livestock and similar traffic may be a problem.
77:05G-037
WATER QUALITY CAN AFFECT MANAGEMENT PLANNING,
Ross, R.
Irrigation Age Magazine.
Irrigation Age, Vol. 12, No. 1, p 60,63, September 1977. 1 fig.
Descriptors: Sodium, Salts, Saline water, Soils, Irrigation, Irrigation effects,
Irrigation practices, Water quality.
What if water is carrying a heavy load of sodium or other salts? Over a period of
time, particularly on a fine-textured soil, a high concentration of sodium could
change the character of the soil so that water could no longer penetrate it, A
large amount of total salts could cause an "artificial drouth," High sodium and/
or too much total salts are among the primary reasons that irrigation water which
may appear to be fine may, in fact, be of poor quality. And once water quality
becomes bad, you have what one expert we visited called a "serious question with
very few good answers."
77:05G-038
ANNOTATED BIBLIOGRAPHY FOR WATER QUALITY MANAGEMENT,
United States Environmental Protection Agency, Water Planning Division, 401 M
Street, S.W., Washington, D.C. 20460.
Annotated Bibliography for Water Quality Management, Fourth Edition, May 1977,
p 1-59.
Descriptors: Water quality. Water quality control, Pollutant identification, Agriculture,
Hydrology, Groundwater,- Water pollution, Pollution, Model studies.
232
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This bibliography has been prepared to assist those who are engaged in 208 water
quality management. References cited have been selected for their applicability
to water quality management and for their availability. A table of contents ar-
ranging the 226 references has been included. Each reference is followed by a
short abstract and, whenever possible, by price and ordering information Instruc-
tions for using the Government Printing Office, the National Technical Information
Service, and for ordering books through the EPA Regional offices or the EPA
Water Quality Management Information Center in Washington, D.C,, are included.
77:05G-039
WATER AND ENERGY CONSERVATION THROUGH EFFICIENT IRRIGATION MANAGEMENT,
Stone, L.R.
Kansas State University, Kansas Water Resources Research Institute, Manhattan,
Kansas.
Water Resources Research Conducted at Kansas State University and University of
Kansas, Project Completion Report, PB 273 810, August 1977. 15 p, 2 fig, 7 tab,
7 ref.
Descriptors: Corn, Grain sorghum, Water use, Use rate, Grain yield, Irrigation,
Soil profiles.
In a 3-year study, corn (Zea mays L.) and grain sorghum (.Sorghum bicolor (L) Moench)
yield and water use efficiency was evaluated as influenced by irrigation timing.
The study was located at Tribune (.mean annual rainfall of 17.0 inches) and
Manhattan, (mean annual rainfall of 33.5 inches) Kansas. Treatments consisted of
no in-season irrigation, a single in-season irrigation at one of three different
growth stages, and irrigating at each of the three selected growth stages. Se-
lected growth stages in corn were pre-tassel, silk emergence, and blister; in
grain sorghum they were boot, half-bloom, and soft-dough. Each irrigation was 4
inches at Manhattan and 6 inches at Tribune. All Tribune plots received a pre-
plant irrigation in April of each year. Water was applied to basin plots using
gated pipe. With no in-season irrigation, the 3-year mean grain sorghum yields
were greater than corn yields at both Manhattan and Tribune, The largest 3-year
mean yield for corn receiving a single in-season irrigation was obtained with the
irrigation during silk emergence at both Manhattan and Tjribune, Grain sorghum
yields from the single in-season irrigation treatments were similar and presented
no single time that tended to be superior during the three study years. Corn
responded well to the three in-season irrigations. The grain sorghum yield in-
crease for plots receiving three in-season irrigation as opposed to those re-
ceiving only one in-season irrigation is insufficient to justify the two additional
irrigations.
77:05G-040
CONTROL OF WATER POLLUTION FROM CROPLAND: VOLUME II - AN OVERVIEW,
Stewart, B.A., Woolhiser, D.A., Wischmeir, W,H,, and Caro, J.H.
Agricultural Research Service, United States Department of Agriculture, Washington,
D.C. 20250.
Publication No. EPA-600/2-75-026, June 1976. 187 p, 20 fig, 12 tab, 28 ref.
Descriptors: Runoff, Pesticides, Nutrients, Nonpoint source pollution. Hydrology,
Sediment control, Erosion,
Engineering and agronomic techniques to control sediment, nutrient, and pesticide
losses frrm cropland are identified, described, and evaluated. Methodology is
developed to enable a user to identify the potential sources of pollutants, select
a list of appropriate demonstrated controls, and perform economic analyses for
final selection of controls. The basic principles on which control of specific
pollutants is founded are reviewed, supplementary information is provided, and some
of the documentation used in Volume I is presented. Volume I (Report No. EPA-600/
2-75-026a) is available from NTIS as report no. PB 249^-517.
CONTRQL°OF SEDIMENTS, NUTRIENTS, AND ADSORBED BIOCIDES IN SURFACE IRRIGATION RETURN
FLOWS,
SniS's^t;; 'Agriculture, Agricultural Research Service, Western Region,
Snake River Conservation Research Center, Kimberly, Idaho 83341.
Publication No. EPA-600/2-76-237, October 1976. 45 p, 2 fig, 7 tab, 49 ref.
(See 77:04A-042)
233
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SECTION XXVIII
WATER RESOURCES AND PLANNING
TECHNIQUES OF PLANNING (GROUP 06A)
77:06A-001
A PROCESS FOR IDENTIFYING, EVALUATING AND IMPLEMENTING SOLUTIONS FOR IRRIGATION
RETURN FLOW PROBLEMS,
Vlachos, E., Barrett, J.W.H., Huszar, P., Layton, J.J., and Radosevich, G.E,
Colorado State University, Department of Sociology, Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 435-445, May 16-19, 1977.
1 fig, 1 tab.
Descriptors: Technology, Water quality, Water quality control, Return flow,
Pollution, Economics.
The purpose of this study has been to develop an effective process for implementing
technical and institutional solutions to the problem of return flow pollution.
The process developed is to: (1) define the problem in terms of its legal, physical,
economic and social parameters, (2) identify potential solutions in relation to the
parameters of the problem, (3) test the implementability of these potential solu-
tions for diverse situations, and (4) specify those solutions or groups of solu~
tions which are the most effective in reducing pollution and are implementable.
This process is initially conceptualized in the paper and then the general results
of its application to three study areas in the western United States are suite-
marized.
77:06A-002
SEASONAL AND STOCHASTIC FACTORS IN WATER PLANNING,
Bishop, A.B., and Narayanan, R.
Utah State University, Utah Water Research Laboratory, Logan, Utah.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY10, p 1159-1172, October 1977. 3 fig, 9 tab, 12 ref.
Descriptors: Water, Water quality, Irrigation, Model studies, Waste water, Waste
water treatment.
Three contrasting formulations of a water allocation model were developed for this
study; linear versus nonlinear costs, annual versus seasonal timeframe, and deter-
ministic versus stochastic water supplies. In general, more information as to
optimal planning configurations was obtained using the more realistic nonlinear,
seasonal-stochastic model. The seasonal model gives better indication of facility
sizing needed for wastewater treatment and results in overall lower costs than the
annual model does, This is particularly important in the summer season when large
volumes of secondary treated effluent are used for irrigation. Because of the
stochastic variability of surface water more dependable, but more expensive, water
sources are indicated in the optimal solution, resulting in higher costs,
77:06A-003
INNOVATIVE MANAGEMENT CONCEPT FOR 208 PLANNING,
Bulkley, J.W., and Gross, T.A,
Michigan University, Department of Civil Engineering and Natural Resources, Ann
Arbor, Michigan.
Journal of the Water Resources Planning and Management Division, American Society
of Civil Engineers, Vol. 103, No. WR2, p 227-240, November 1977, 4 fig, 16 ref.
Descriptors: Agriculture, Return flow, Water quality, Water quality control,
Water pollution. Water pollution control.
234
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Area-wide (Section 208} water quality planning is an ongoing activity in 176 areas
throughout the United States. A major component of the Section 208 planning is the
designation of a management agency (ies) to actually implement the water quality
plans for each 208 area. For reasons not dissimilar to water management problem
situations in this country, the English and Welsh have recently reorganized their
management structure for provision of comprehensive water services. In England and
Wales the emphasis is a regional approach for comprehensive water resource planning
and management. Detailed information has been presented upon one of the new
Regional Water Authorities, the Thames Water Authority. Criteria have been identi-
fied which should be of use in evaluating alternative management structures in the
context of section 208 management structure efforts. These criteria have been
evaluated in a preliminary examination against the present arrangements for pro-
vision of water services in three complex urban areas in the United States; Cleveland,
Chicago, and Detroit. In addition, the Thames Water Authority has been assessed
against these criteria. '
77:06A-004
FIELD EVALUATION OF SOME PUBLIC INVOLVEMENT TECHNIQUES,
Ortolano, L., and Wagner, T.P,
Stanford University, Department of Civil Engineering, Stanford, California 94305.
Water Resources Bulletin, Vol. 13, No, 6, p 1131-1139, December 1977, 1 tab,
11 ref.
Descriptors: Water resources, Water resources development, Water law. Planning,
Public rights.
Public involvement in water resources planning is receiving much current attention,
and there is a need to examine systematically how different public involvement
techniques work in practice. The following techniques were among those used to
involve the public in a recent Corps of Engineers' study of flooding on San Pedro
Creek in Pacifica, California: a public workshop, citizen information bulletins
(CIBs) and questionnaires. Interviews were held with 75 study participants to
evaluate the effectiveness of these techniques. The interviews indicated that
various study participants felt positively about the particular workshop format
employed and about the use of a communications specialist to train workshop leaders.
There were mixed reactions to the effectiveness of the CIBs and questionnaires.
Although many individual citizens felt that the CIBs and questionnaires were use-
ful, some of the Corps planners felt that CIB*s and questionnaires would only be
"cost-effective" on large studies and/or where the questionnaire response rate
wa% high.
77:06A-005
NEW REQUIREMENTS FOR LOCAL UNITS OF GOVERNMENT IN WATER RESOURCES PLANNING; INSIGHTS
FOR IMPLEMENTATION FROM RECENT WATER RESOURCES PLANNING RESEARCH,
Say, E.W., and Dines, A.J.
E.W. Say & Associates, Incorporated, 9741 Liberty Road, Chelsea, Michigan 48118.
Water Resources Bulletin, Vol. 13, No. 5, p 907-915, October 1977, 1 fig, 2 tab,
7 ref.
Descriptors: Water resources, Water resources development, Watersheds, Water law,
Environmental effects, Water supply, Water allocation (policy).
Recent Federal and some State legislation has enlarged the scope of permitted or
required actions of local units of government in water resources management and
protection. Much of the legislation encourages local units of government to intro-
duce water resources planning measures which will be preventive instead of corrective.
Extensive public works measures, environmental destruction and the threat to human
life can thus be eliminated or reduced. Research has developed and tested a method
for identifying the elements of a water resources protection program for small
urbanizing watersheds which was technically adequate and socially acceptable to the
communities implementing such programs. Research results suggest that deliberate
efforts will be necessary to inform and educate local units of government as to the
usefulness of the legislation; and that the program must reflect local natural
resource conditions and local preferences for the method of accomplishing the
protection. Successful implementation could be restrained by inertia of local
units of government, a lack of tradition in such programs, and hostile existing
agencies.
235
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77:06A-006
ASSESSMENT OF IRRIGATION RETURN PLOW MODELS,
Walker, W.R.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Publication No. EPA-600/2-76-219, October 1976. 75 p, 4 fig, 11 ref, 7 append.
Descriptors: Return flow, Water quality, Model studies, Soils, Aquifer systems.
Crops, Application methods, Irrigation, Salinity, Mathematical models, Soil
chemistry, Water consumption, Drainage, Leaching.
Throughout the Western United States irrigation return flows contribute to the
problem of water quality degradation. Evaluating the effectiveness of alternative
management strategies involves models which simulate the processes encompassed by
irrigated agriculture. The development and application of these models require
multidisciplinary expertise. A workshop involving 15 specialists in the varied
aspects of irrigation return flow modeling was held to review the status of these
models. Irrigation return flow and conjunctive use models recently developed by
the Bureau of Reclamation served as focal points for the workshop. As the field
verification and potential applications of these models were discussed, several
general problems were identified where further investigation is needed. Particular
emphasis was given to the description of the spatially varied aspects of soil, crop,
and aquifer systems, and the proper alignment of model objectives with available
data. The large number and diversity of existing models illustrate the individualis-
tic nature of irrigation return flow modeling. In order to affect more wide-
spread utilization of existing models, a systematic procedure should be developed
to update and disseminate this modeling technology.
236
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SECTION XXIX
WATER RESOURCES PLANNING
EVALUATION PROCESS (GROUP 06B)
77:066-001
PUBLIC PARTICIPATION IN WATER RESOURCE DEVELOPMENT,
Silberman, E,
Minnesota University, Saint Anthony Falls Hydrology Laboratory, Minneapolis,
Minnesota.
Journal of the Water Resources Planning and Management Division, Proceedings
of the American Society of Civil Engineers, Vol. 103, No, WR1, Proceedinqs Paper
No. 12952, p 111-123, May 1977. 15 ref.
Descriptors: *Water resources development, *Social participation, *Public benefits,
Planning, Social needs, Flood control, Minnesota.
The objectives of a public participation program should be to assure that planners
and public have similar concepts of what the problems are and that the proposed solu-
tions are perceived as solutions by both planners and public. Elements of a public
participation program are identifying the public, reaching the public, and deter-
mining what the public wishes are. These elements are analyzed by recounting the
experience of the Bassett Creek Flood Control Commission in establishing a flood
control plan for an urbanized and urbanizing area in Minneapolis metropolitan area.
The Commission is composed of nine volunteer commissioners, one appointed by each
of the nine cities in the basin. The Commission (with the aid of its consulting
engineers) was very effective in melding bureaucratic and public input into an
acceptable plan where a previous plan prepared under the auspices of a bureaucratic
organization was practically shouted down.
77:066-002
WATER RESOURCES PLANNING AND MANAGEMENT GOALS,
Gaum, C.H.
Corps of Engineers, Central Reports Management Branch, Washington, D,C.
Journal of the Water Resources Planning and Management Division, Proceedings of
the Society of Civil Engineers, Vol. 103, No. WR1, Proceedings Paper No. 12941,
p 73-82, May 1977. 2 fig, 4 tab.
Descriptors: *Planning, *Decision making, *Priorities, *Management, Water resources
development, Water management (.applied), Environmental effects, Regions, Projects.
The goal of water resources planning and management is to utilize water related
sources for national economic gain, regional development, enhancement of the
environment, and the provision of social betterment. It must be recognized that
because of great demands, the resources, including dollars, must be economically
managed. Only those projects having high justification will be placed in the
budget cycle for implementation. Water resources planners must develop new tech-
niques to shorten the time required to plan and foreset priorities. They must
improve reporting methods and present all relevant factors. By doing so, they
will be playing a more decisive role in the decision-making process.
237
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SECTION XXX
WATER RESOURCES PLANNING
COST ALLOCATION, COST SHARING, PRICING/REPAYMENT (GROUP O6C)
77:06C-001
CENTER PIVOTS: FINANCING OR LEASING?
LoBello, A.J,
C.I.T." Corporation, National Marketing Division.
Irrigation Journal, Vol. 27, No, 4, p 16-17, July-August, 1977. 1 fig, 1 tab.
Descriptors; Irrigation, Irrigation systems, Sprinkler irrigation, Economics,
Financing, Leases,
Center pivot systems are the £astest-growing sector of the irrigation equipment
market. Of the two million acres coming under irrigation each year, it is esti-
mated that 60% now are center pivot, with the market growing about 15% each year.
At that rate, center pivot can be expected to constitute up to half of the sy-
stems in the United States in future years, and a total of some 50 million acres
will come under this type of irrigation. Center pivot systems currently run
from $30,000 to $60,000 per unit. So, next to the right irrigation system for
his needs, the ability to offer a customer the best financing package is one of
the most important marketing tools a dealer has,
77:06C-002
WHICH METHOD IS BEST FOR YOU?: IRRIGATION COSTS,
Water and Irrigation, p 12-13, 24-25, November 1977, 3 fig, 2 tab,
Descriptors: Irrigation systems, Irrigation practices, Economics, Cost analysis,
Cost comparisons, Costs, Furrow irrigation, Sprinkler irrigation, Surface ir-
rigation.
One of the most persistent questions in the minds of farmers who are considering
changing their method of irrigation, is "What will it cost?" The Cooperative
Extension Service of the University of California assigned several of its experts
to provide a perspective on irrigation costs in California,
238
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SECTION XXXI
WATER RESOURCES PLANNING
WATER DEMAND (GROUP 06D)
77:060-001
ARID AND SEMI-ARID LANDS: PROBLEMS AND PROSPECTS,
Kassas, M.
Cairo University, Department of Science, Giza, Egypt.
Agro-Ecosystems, Vol. 3, No. 3, p 185-204, June 1977. 23 ref.
Descriptors: Deserts, Arid lands, Water, Climates, Agriculture, Semiarid
climates, Population.
A survey of the world's deserts and processes of desertification identifies those
that are strictly due to physical factors and those that are anthropogenic.
Areas of potential useful study are identified: Improved climate, climatic re-
search and monitoring, improvement of arid zone cultivars, improved techniques
of decision-making about land use. Warnings are given of the dangers of over-
intensification of agricultural systems and of increasing population density
in arid zones. Research areas suitable for international cooperation are
outlined.
77:060-002
ANALYSIS OF WATER REQUIREMENTS FOR AGRICULTURAL IRRIGATION IN PENNSYLVANIA,
Kibler, D.F., Fritton, D.D., White, E.L., Trotter, R.J., and Tandy, D,F.
The Pennsylvania State University, Institute for Research on Land and Water
Resources, University Park, Pennsylvania 16802,
Bureau of Resources Programming, Research Publication 99, September 1977, 228 p,
28 fig, 35 tab, 6 ref.
Descriptors: Irrigation, Crop production, Climates, Irrigation water, Crops,
Application methods, Soil moisture. Hydrology, Water demand.
In any study which seeks to project the irrigation water needs for an area, it is
important to identify the crops which are likely to be irrigated. Of course, all
crops would be listed if the area were located in a desert. In a humid region
like Pennsylvania, the decision is not as straightforward. In this report, the
objective is to identify the crops which are likely to be irrigated under
Pennsylvania's climatic conditions. The decisions in this chapter are made on
the basis of the historical use of irrigation research experiments and other
carefully documented investigations which apply. The attempt is to base decisions
on documented yield increases of a crop under irrigated conditions when compared to
yields produced by natural rainfall, Whether these yield increases would pay for
an irrigation system is beyond the realm of this study.
239
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SECTION XXXII
WATER RESOURCES PLANNING
WATER LAW AND INSTITUTIONS (GROUP O6E)
77:06E-001
A VALLEY - WIDE SOLUTION,
Beck, L.A.
San Joaquin Valley Interagency Drainage Program, Fresno, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 297-298, May 16-19, 1977,
Descriptors: Drainage practices, California, Return flow.
The San Joaquin Valley Interagency Drainage Program (IDP) is an action-oriented
program with objectives including: 1) coordination of the on-going drainage
water management activities of the cooperating agencies (USER, SWRCB, and DWR);
2) development of alternative plans for managing the drainage waters; 3) determi-
nation of potential uses for drainage waters; 4) development of a recommended
plan for managing drainage waters; and 5) recommending ways to finance drainage
facilities.
77:06E-002
THE 1973 AGREEMENT ON COLORADO RIVER SALINITY BETWEEN THE UNITED STATES AND MEXICO,
Holburt, M.B.
Colorado River Board of California, Los Angeles, California.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 325-333, May 16-19, 1977,
1 fig.
Descriptors: Water quality, Water quality control, Colorado River, Salinity,
Mexico.
The background of the conflict between the United States and Mexico over the salinity
of the Colorado River water delivered to Mexico, the early attempts to resolve the
conflict, the meetings and negotiations that led to the latest agreements, a descrip-
tion of the agreement, the legislation that implements that agreement, and necessary
future actions are presented.
77:.06E-003
THE EPA GENERAL PERMIT PROGRAM,
Anderson, K.
United States Environmental Protection Agency, Washington, D.C,
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 397-404, May 16-19, 1977.
Descriptors: Agriculture, Water quality, Water quality control. Irrigation, Return
flow.
The Environmental Protection Agency (EPA) has developed a General Permit Program
under the National Pollutant Discharge Elimination System (NPDES) which applies
to both separate storm sewers and agricultural point sources (irrigation return
flow conveyances), The proposed rules for this general permit program were printed
in the Federal Register, Vol. 42, No. 24, February 4, 1977. This paper provides
a guide as to how the General Permit Program is intended to function,
240
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77:06E-004
INTERFACE OP WATER QUANTITY AND QUALITY LAWS IN THE WEST
Radosevich, G.E. '
Colorado State University, Department of Economics, Fort Collins, Colorado
80523
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 405-422, May 16-19. 1977.
1 t3.t> *
Descriptors: Water law, Water pollution, Agriculture, Return flow, Water quality,
Water qualxty control, Water resources, Water rights, Irrigation.
Water pollution from irrigated agriculture in the West has received major attention
during the past five years, primarily as a result of federal and state endeavors
to identify irrigation return flow quality problems and to develop a viable
control strategy. The national goal of "cleaner water" emerged as a result of the
deterioration of water quality by degraded discharges from various sources. The
key to irrigated agricultural return flow quality control is proper utilization
and managment of the resource itself, and an accepted tool in our society is the
law. By legal classification, it is divided into laws for quantity control and
laws for quality control. The laws on water quality control are recent, relatively
uniform between states and with little exception, constrain improvement of return
flows from irrigated agriculture. Unfortunately, in most others, they cannot really
be said to facilitate this consequence either. The laws pertaining to water re-
sources quantity control and management are complex, voluminous, inconsistent and
lack uniformity among the 17 states of the West.
77:06E-005
AN INFLUENT CONTROL APPROACH TO IRRIGATION RETURN FLOW QUALITY MANAGEMENT,
Radosevich, G.E., and Skogerboe, G,V.
Colorado State University, Department of Economics, Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 423-434, May 16-19, 1977.
5 fig.
Descriptors: Water quality control, Agriculture, Water quality, Irrigation,
Return flow. Water rights.
The Influent Control Approach is based upon the assumption that improved water
management plus improved agricultural practices will significantly contribute to
improved water quality, and the conclusion that best management practices plus
best agricultural practices will provide irrigation return flow quality control,
which in turn will contribute significantly to the national goal of cleaner water
through improved water quality. The Influent Control Approach consists of eight
specific components: (1) designate areas for irrigation return flow quality
management and designate the responsible area entity; (2) develop standards and
criteria for beneficial use in designated areas; (.3) introduce incentives to use
water more efficiently; (4) include the element of water quality in new or trans-
ferred and changed water rights; (5) adopt and enforce a reporting and recording
system for water rights; (6) recognize reasonable degradation from agricultural
water use; and (7) adopt an Agricultural Practices Act; and (..8) promote close
cooperation or integration of state water agencies and related functions.
77:06E-006
ECONOMIC IMPACTS OF ADMINISTRATIVE WATER LAW SYSTEMS,
Kiker, C.P.E., and Lynne, G.D. .
Florida University, Department of Food and Resource Economics, Gainesville,
Florida. -, ^ T
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-22. 20 ref, 13 equ.
Descriptors: Legal aspects, Legislation, Water law, Economics,
There is a move to administrative regulation of water in th« e^ states
Economic efficiency is largely being ignored in allocation of Pte entitle
ments to water. Several allocation alternatives that include economic criteria
are examined.
241
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77:06E-007
SOIL EROSION AND SEDIMENTATION: ANALYSIS OF APPLICABLE LAW,
Walker, W.R., and Cox, W.E.
Virginia Water Resources Research Center, Blacksburg, Virginia.
Presented at the Annual Meeting, American Society of Agricultural Engineers,
June 26-29, 1977, Raleigh, North Carolina, North Carolina State University,
p 1-12. 16 ref.
Descriptors: Soil erosion, Erosion, Sedimentation, Legislation, Legal aspects.
Law applicable to activities that increase erosion and sedimentation exists in a
variety of forms. The trend in the development of such law has been toward an
expansion in scope of activities encompassed and an increase in the degree of
legal accountability imposed for resulting injury.
77:06E-008
EXPERIENCE WITH THE 303-208-201 STUDY RELATIONSHIPS,
Dobrowolski, F.r and Grillo, L.
Clinton Bogert Associates, Fort Lee, New Jersey 07024.
Water Resources Bulletin, Vol. 13, No. 3, p 455-460, June 1977.
Descriptors: New Jersey, Municipal water, Water quality, Water quality control,
Water pollution, Water quality standards, Water resources.
The current 201 study by the Bergen County Sewer Authority illustrates possibilities
for improving the currently defined relationships between 201, 208 and 303 studies,
The Bergen County Sewer Authority serves 115 square miles in northeast New Jersey,
providing sewerage service to 507,000 people in 43 municipalities. Its STP dis-
charges to the Hackensack River, a tidal estuary recently classified as Water Quality
Limited, and which receives significant nonplant loading. The subject 201 study is
concurrent with 208 and 303 planning by NJDEP, Preliminary evaluations show that
detailed 201 work can affect the conclusions of 303 and 208 studies, and that a
wider (environmental-social as well as economic) interpretation of cost-effectiveness
can demand reexamination of prior assumptions and decisions, a task not typically
part of 208-303 work.
77:06E-009
INVESTOR OWNED VS. PUBLICLY OWNED WATER AGENCIES; AN EVALUATION OF THE PROPERTY
RIGHTS THEORY OF THE FIRM,
Morgan, W.D.
California University, Department of Economics, Santa Barbara, California 93106,
Water Resources Bulletin, Vol. 13, No. 4, p 775-781, August 1977. 2 tab, 8 ref,
1 equ.
Descriptors: Water, Water resources, Water law, Water costs, Water allocation
(policy).
The property rights theory of the firm is evaluated by comparing the cost structures
of a sample of water agencies under two alternative modes of ownership - public
and investor owned. On the basis of the sample, investor owned water agencies appear
to have lower cost structures.
77:06E-010
DEVELOPING COMPETITION FOR WATER IN THE URBANIZING AREAS OF COLORADO,
Anderson, R.L., and Wengert, N.I.
Colorado State University, Department of Economics, Fort Collins, Colorado 80523.
Water Resources Bulletin, Vol. 13, No. 4, p 769-773, August 1977. 2 tab, 1 ref.
Descriptors: Colorado, Water resources, Water allocation (.policy), Irrigation
water, Agriculture, Municipal water, Water supplies.
Rapid population growth in the metropolitan area of Denver, Colorado, is causing
conflicts over water use. Two cities, Thornton and Westminster, have begun
condemnation proceedings against three irrigation companies to secure agricultural
water rights for municipal use. This is the first condemnation proceeding against
irrigation water rights for municipal use. Should the suit succeed, over 30,000
242
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acres of presently irrigated land will lose its water supply. There are about
four hundred landowners in the area; two hundred of these are cornierical farmers
including truck, dairy and specialty farms. Total agricultural production amounts
to about $8 million per year. About 561 jobs related to agriculture will dis-
sappear along with about $4 million in net income.
77:06E-011
WATER RIGHTS, EMINENT DOMAIN, AND THE PUBLIC TRUST,
Radosevich, G.E., and Sabey, M.B.
Colorado State University, Department of Economics, Fort Collins, Colorado 80521
Water Resources Bulletin, Vol. 13, No, 4, p 747-757, August 1977. 12 ref.
Descriptors: Water law, Water resources, Water allocation (policy), Agriculture,
Colorado, Municipal water, Irrigation water.
Faced with the necessity of meeting growing municipal water requirements in areas
where available supplies are completely allocated, numerous cities throughout the
West are turning to their eminent domain powers to affect a reallocation of water
from less preferred uses to municipal uses, thus bringing about a sharp conflict
with agricultural interests. As a basis for discussing these eminent domain powers,
this paper begins with a brief review of the development of property rights. The
existence of both private and public (social) rights in the "bundle of rights1' is
noted. . In recent years the Public Trust Doctrine has been used to limit private
rights in property, and to protect and strengthen social rights, A case study
which focuses on a conflict between individual and social interests in water rights
is discussed. This case involves the City of Thorton, Colorado which initiated
municipal condemnation proceedings to acquire the water rights and structures of
two nearby irrigation companies. The case represents an attempt to incorporate the
spirit of the Public Trust Doctrine into legislation which sets forth procedures
for resolution of similar water rights conflicts that will inevitably become more
numerous throughout the West in the future,
77:06E-012
IRRIGATION TECHNOLOGY AND AGRICULTURE PRODUCTION,
Logan, D.
Western Empire Corporation, Irrigon, Oregon.
Proceedings of the 1977 Annual Technical Conference, Irrigation For All Reasons,
p 178-180, February 13-15, 1977.
Descriptors: Irrigation, Irrigation practices, Irrigation effects, Agriculture,
Crop production, Oregon,
An irrigation farmer elaborates on his views of irrigated agricultural develop-
ment and irrigation technology.
77:06E-013
WINTER'S DOCTRINE: A REVIEW,
Bird, J.W.
Nevada University, Department of Civil Engineering, Reno, Nevada.
Journal of the Irrigation and Drainage Division, Vol. 103, No, IR4, p 395-400,
December 1977. 9 ref, 1 append.
Descriptors: Appropriation, Beneficial use, Federal government. State government,
Water law, Water rights.
The western states are areas of short water supply. In general, they apply the
water law doctrine of appropriation that relates a water right to the time or
date that the right started. The Federal government has applied for wat« rights
at a much later time, but with an early appropriation, date. Th« «°"Jd |^eb^
Federal agencies priority over the existing water users, many °f£hich have been
beneficially using the water for years, Since the Federal agencies Wrently
have decided, through the courts, their ability to act unilaterally in this matter,
it is apparent that'guidance from the Congress is £«£^gnJ^S %ES water
Otherwise the state's water laws shall be greatly weaxenea, a. y
planning and policy.
243
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77:06E-014
ON THE ALLOCATION OF PRIME AGRICULTURAL LAND,
Gibson, J.A.
Harza Engineering Company, Department of Economics, 150 South Wacker Drive,
Chicago, Illinois 60606.
Journal of Soil and Water Conservation, Vol. 32, No, 6, p 271-275, November-
December, 1977. 27 ref.
Descriptors: Land, Land classification, Land development, Land management, Land
resources, Land use, Agriculture, Environment, Environmental control, Economics,
Urbanization.
How land is used in the future likely will vary considerably from how land should
be used according to economic theory. Asymmetry characterizes the effectiveness
and efficiency of our system of economic incentives. A major part of land use is
formed by the sum of many individual local actions. The present market system
stimulates the exploitation of land resources very well, but it fails almost com-
pletely with respect to preservation. For example, climate, topography, and soils
exert all-important effects upon the use of land for agricultural purposes. The
location factor is of little significance for agriculture in the absence of a
suitable physical base.
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SECTION XXIII
RESOURCES DATA
DATA ACQUISITION (GROUP 07B)
77:07B-001
AN EVALUATION OF SOME FLUORESCENT DYES FOR WATER TRACING
Smart, P.L., and Laidlaw, I.M.S.
Bristol University, Department of Geography, (England).
Water Resources Research, Vol. 13, No. 1, p 15-33, February 1977. 19 fig, 11 tab,
77 ref.
Descriptors: *Fluorescent dye, *Water chemistry, *Tracers, *Dyes, Water, Amino
acids, Rhodamine, Laboratory tests, Toxicity, Filters, On-site tests.
Eight fluorescent dyes (ainino G acid, photine CU, fluorescein, lissamine FF, py-
ranine, rhodamine B, rhodamine WT, and Sulpho rhodamine B) were compared in labora-
tory and field experiments to assess their utility in quantitative tracing work.
The properties considered included sensitivity and minimum detectability, the ef-
fect of water chemistry on dye fluorescence, photochemical and biological decay
rates, adsorption losses on equipment and sediments, toxicity to man and aquatic
organisms, and cost. The orange fluorescent dyes are more useful than the blue
and green dyes because of the lower background fluorescence at the orange wave
band, which permits higher sensitivities to be obtained. Pyranine fluorescence
is strongly affected by pH over the range encountered in natural waters, which pre-
cludes its simple use in quantitative work. Amino G acid, photine CU, pyranine,
and fluorescein all have high photochemical decay rates. Pyranine, lissamine FF,
and amino G acid are the dyes most resistant to adsorption, but rhodamine WT,
fluorescein, and sulpho rhodamine B also have moderately high resistance. Rhodamine
B is readily adsorbed by most materials. Rhodamine WT (orange), lissamine FF
(green), and amino acid. G acid (blue) are the three tracer dyes recommended. These
3 dyes can be used simultaneously to trace three injection sites with the filter
combinations suggested.
77:07B-002
TWO NEW METHODS FOR OBTAINING WATER SAMPLES FROM SHALLOW AQUIFERS AND LITTORAL
SEDIMENTS,
John, P.H., Lock, M.A., and Gibbs, M.M.
Department of Scientific and Industrial Research, Ecology Division; and Department
of Scientific and Industrial Research, Freshwater Section, Taupo (New Zealand).
Journal of Environmental Quality, Vol, 6, No. 3, p 322-324, July-September, 1977.
5 fig, 6 ref.
Descriptors: *Water sampling, *Aquifers, *Sediments, *Littoral, Groundwater,_
Methodology, Instrumentation, Monitoring, Geochemistry, Wellpoints, Plastic pipes,
Water table. Nutrients, Foreign research.
Two sampling techniques were developed which enable groundwater samples to be ob-
tained from various depths within shallow aquifers and littoral sediments Both
techniques involve the insertion of a percussion-driven spike to the desired depth.
One method employs a sampling probe consisting of a perforated tip and a mechanism
for the prevention of blockage by grit during the driving Process, «^h **^
being withdrawn through an internal plastic tube. The other technique ^olves
permanent installation of a perforated plastic tubing. Som^^a^^"°fdChe^C^s
data obtained during extensive testing of these tecf^ues were presented investi-
concluded that the techniques could have considerable application in the investi
gation of shallow groundwater and littoral sediment chemistry,
77:07B-003 r^mar w nTPPFRFNCE AND 15N A-VALUES IN LYSIMETERS,
CLOVER N-FIXATION MEASUREMENT BY TOTAL-N DIFFERENCE AWU
Williams, W.A., Jones, M.B., and Delwiche, C.C.
245
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California University, Department of Agronomy, Davis, California.
Agronomy Journal, Vol. 69, No. 6, p 1023-1024, November-December, 1977. 1 fig,
1 tab, 6 ref.
Descriptors: Nitrogen, Legumes, Leaching, Lysimeters, Clovers, California, Crop
production, Crop response.
Assessment and improvement of N fixation by legumes on annual-type range is be-
coming increasingly important in light of the increasing need for energy conserva-
tion. A comparison was made of two methods of assessing N fixation: a simple but
crude method by measuring the total-N difference in tops of an N-fixing legume and
a non N-fixing grass, and a more expensive method using A-values determined from
15N applications to the same legume and grass species. Subterranean clover and
soft chess grass were grown in field lysimeters (69 cm deep by 36 cm diam.) filled
with Josephine loam (Typic Haplozerults, fine loamy, mixed mesic) for 3 years.
Single (100 and 500 kg/ha) and repeated (100 kg/ha) applications "of 15N were made
and determinations were made of soil and fertilizer N in the plants, soil, and
leachate periodically. The relation between the two methods was strongly linear;
fixation (kg/ha) by the A-value method = 50.1 + 0.852 N fixation by difference
(r = 0.98, n = 15). Consequently, previous values cited for N fixation measured
by the difference method for winter annual legumes in California may have been
underestimated by about 40%.
77:07B-004
EVALUATION OF A WATER ANALYSIS KIT,
Boyd, C.E.
Auburn University, Department of Fisheries and Allied Aquaculture, Auburn, Alabama
36830.
Journal of Environmental Quality, Vol. 6, No. 4, p 381-384, October-December, 1977.
3 tab, 10 ref.
Descriptors: Laboratory tests. Laboratory equipment, Water analysis. Water chemistry,
Water pollution. Water pollution control, Water quality, Water quality control,
A Hach DR-EL/2 Direct Reading Engineer's Laboratory Kit was evaluated by comparison
to standard analytical methods. Results of Hach kit methods were highly correlated
with concentrations of standard solutions. The y-intercepts (a) did not differ from
0 for most methods, but for 11 methods regression coefficients (b) differed from 1.0.
For each of the 20 parameters, three natural water samples were analyzed seven times
by Hach kit and by the standard method. Mean values obtained by the two analytical
systems were usually significantly different and the standard method sometimes gave
higlec precision than the Hach kit. Nevertheless, the Hach kit usually gave close
approximations of values obtained by standard methods. Comparisons also included
analyses of a large series of natural water samples. Correlation coefficients bet-
ween Hach kit and standard methods were often greater than 0,00, Although a = 0
for 14 methods, b = 1.0 for only 8 methods. Reliability of the Hach kit was adequate
for general surveys of water quality, fisheries management decisions, and research
requiring only approximate data on water quality.
77:076-005
INTEGRATED AUTOMATIC WATER SAMPLE COLLECTION SYSTEM,
Fisher, P.D., and Siebert, J.E.
Michigan State University, Department of Electrical Engineering and Systems Science,
East Lansing, Michigan.
Journal of the Environmental Engineering Division, American Society of Civil Engineers,
Vol. 103, No. EE4, p 725-728, August 1977, 3 fig.
Descriptors: *Water sampling, *Data collections, *Equipment, Stream gages, Sampling,
Water chemistry. Water pollution, Hydrologic data, Automation, Electrical equipment,
Electronic equipment, Hy.drographs, Hydrology.
Reported in this paper were the organizations, operation, and utility of an automatic
water sample collection, a modified hydrographic recorder, and a specially designed
auxiliary electronic controller. The integrated water sampling system expands the
normal operating capabilities of the conventional automatic water sampler and hydro-
graphic recorder.
246
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77:07B-006
FOUR-ELECTRODE CONDUCTIVITY RELATIONSHIPS FOR SOILS OF THE NORTHERN
o /
Halvorson, A.D., Rhoades, J.D., and Reule, C.A.
United States Department of Agriculture Agricultural Research Service, Department
of Soil Science, Post Office Box 1109, Sidney, Montana 59270
f°i* Science Society of America Journal, Vol. 41, No. 5, p 966-971, September-October,
1977. 4 fig, 5 tab, 12 ref.
Descriptors: Soils, Soil investigations, Salinity, Saline soils, Soil textures
Electrical conductance, Clays, Soil water, Soil moisture. '
Influence of soil texture, soil geographic location and parent material, and calibra-
tion method on the linear ECe-ECa relationship was investigated. Linear regression
relationships between saturation extract electrical conductivity (.ECe) and bulk soil
electrical conductivity (ECa) as measured by the four-electrode technique was developed
for northern Great Plains soils. Most correlation coefficients (r) exceeded 0.95 and
all were significant at the 0.01 probability level. Geographic location had little
effect on the ECe vs. ECa relationship; therefore, an ECe vs. ECa calibration made
for a soil textural class at one location will apply to another location having a
similar range in soil water, clay content, and salinity. Clay content affected
linear regression line slopes more than did other factors investigated. Regression
slopes varied from 3.06 for a clay to 12.99 for a loamy sand over the clay concen-
tration "range of 63.0 to 6.5 percent, respectively. To minimize adverse effects
caused by natural variation in soil texture, water content, and salinity when making
field ECe vs. ECa calibrations, we suggest artificial salinization of columns of
the soil type in question, which will permit subsequent analysis of the soil by
either the cell or EC-probe calibration method.
77:07B-007
A LABORATORY TECHNIQUE FOR APPRAISING IN SITU SALINITY OF SOIL,
Mubarak, A. , and Olsen, R.A.
Montana State University, Department of Chemistry, Bozeman, Montana.
Soil Science Society of America Journal, Vol. 41, No. 5, p 1018-1020, September-
October, 1977. 2 fig, 2 tab, 14 ref.
TSee 77:02G-083)
77:07B-003
GAS CHROMATOGRAPHIC ANALYSIS OF SOIL ATMOSPHERES,
Blackmer, A.M. , and Bremner, J.M.
Iowa State University, Department of Agronomy, Ames, Iowa 50011,
Soil Science Society of America Journal, Vol. 41, No, 5, p 908-912, September-
October, 1977- 4 fig, 2 tab, 25 ref.
Descriptors: Sampling, Soil investigations, Soils, Soil environment, Soil properties,
Soil tests.
A gas chromatographic procedure is described that permits rapid, specific, and precise
determination of N2 , 02, Ar, C02 , CH4 , N20, and other gases in soil atmospheres. It
involves use of an ultrasonic detector and two columns of Porapak Q at different
temperatures, and it does not require temperature programming, column conditioning,
stream splitting, column switching, or switching of recorder polarity. Unlike thermal
conductivity and helium ionization detectors previously used for gas chromatographic
analysis of soil atmospheres, the ultrasonic detector is not adversely affected by
gases found in soil atmospheres.
A COMPARISON OF DETERMINISTIC MATHEMATICAL WATERSHED MODELS,
Effects Laboratory, Vicksburg,
Prnted the 1977 Annual Meeting, American Society of
June 26-29, 1977, Raleigh, North Carolina, North Carolina State University, p i
10 fig, 3 tab, 13 ref, 1 append.
Descriptors: Simulation analysis. Model studies, Watershed management, Watersheds
(basins) .
247
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Hydrocomp, SWM, SSARR, HEC-1 and United States Department of Agriculture-HL75 were
reviewed using input data from the Caddo River drainage basin for mathematical
simulation comparisons. The attributes of each model are presented permitting the
selection of a model most appropriate for a specific application to chemical wash-
off algorithms.
77:078-010
IRRIGATION RETURN FLOW MODELINGA STATE OF THE ART,
Walker, W.R.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House, Chicago, Illinois, p 1-18. 4 tab,
54 ref.
Descriptors: Return flow, Model studies, Simulation analysis, Computer programs,
Groundwater, Nitrogen, Irrigation, Irrigation effects.
Forty-three models which have been developed and tested for simulation of irrigation
return flow systems have been collected and evaluated. This paper discusses what
seems to be some of the more critical problems in using these models, the relative
strengths of those existing, and important research and development needs for
maximizing their utilization in the future.
77:07B-011
RAINFALL SIMULATOR FOR EVALUATING EROSION RATES AND SEDIMENT SIZES FROM ROW
SIDESLOPES,
Meyer, L.D., and Harmon, W.C.
United States Department of Agriculture Sedimentation Laboratory, Department of
Agricultural Engineering, Oxford, Mississippi.
Presented at the 1977 Annual Meeting, American Society of Agricultural Engineers,
June 26-29, 1977, Raleigh, North Carolina, North Carolina State University, p 1-12,
9 fig, 8 ref.
Descriptors: Rainfall, Simulation analysis, Rainfall simulators, Runoff, Erosion,
Sediments, Sedimentation, Soil erosion,
A new rainfall simulator was developed for obtaining data on row-sideslope runoff,
erosion, and sediment size. It can apply a wide range of intensities at impact
energies comparable to those of natural rainfall. Design features, simulated-
rainfall characteristics, and example data are reported.
77:07B-012
A NEW APPROACH TO DETERMINATION OF CATION EXCHANGE CAPACITY,
Fernando, M.J., Burau, R.G., and Arulanandan, K,
California University, Davis, California,
Soil Science Society of America Journal, Vol. 41, No, 4, p 818-820. July^-August,
1977. 3 fig, 2 tab, 8 ref.
Descriptors: Sampling, Laboratory tests, Cation exchange, Soils, Soil texture,
Soil investigations, Soil properties.
The dielectric dispersion defined as the difference in the dielectric constant of
a sample measured at 3,000,000 HZ and at 75,000,000 HZ, was linearly related to
CEC of the sample. One linear relationship between dielectric dispersion and CEC
was obtained for clay-silica flour mixtures where CEC was varied by changing the
proportion of clay in the sample as well as by using clays with different CEC (kaoli-
nite, illite, montmorillonite). A second linear relationship, with somewhat dif-
ferent slope, was obtained between the dielectric dispersion and the CEC of natural
soil samples.
77:076-013
CORRECTING TURBIDITY INTERFERENCE IN THE DETERMINATION OF PHOSPHORUS,
Folsom, B.L., Jr., Sunderman, H.D., and Hossmer, L,R.
Texas Agricultural Experiment Station, College Station, Texas.
243
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"' N°- 4' P 823-824' July-
Descriptors: Phosphorus, Ammonium, Turbidity, Sampling, Laboratory tests.
Turbidity caused severe interference in the presence of excess ammonium when
determining phosphorus by the method of Murphy and Riley. The precipitated com-
inea ratio^f^ f"? .Tn ?? ^ C°^osedKof 4 < + > ' antimony, P, and molybdenum
in a ratio of 115. 8 : 1 . 5 : 1 . 0 :11 . 6 . The combination of Sb and NH4 ( + ) in solution
during color development caused the turbidity interference. The turbidity could
be eliminated by raising the pH above 8.2 with NaOH and boiling to drive off
NH4(+) as NH3 gas prior to color development or by substituting heat for Sb to
develop the characteristic molybdenum blue color.
77:07B-014
PHOTOSYNTHESIS OF SUGARBEETS UNDER N AND P STRESS: FIELD MEASUREMENTS AND CARBON
BALANCE ,
Gary, J.W.
Snake River Conservation Research Center, Department of Soil Science, Kimberlv
Idaho 83341. ' '
Agronomy Journal, Vol. 69, No. 5, p 739-744. September-October, 1977. 7 fig,
1 tab, 10 ref.
Descriptors: Crop production, Photosynthesis, Sugar beets, Phosphorus, Nitrogen,
Carbon, Crop response, Nutrients, Fertilizers, Fertilization,
Advances in crop management are limited by inability to recognize changes in
growth resulting from short-term fluctuations in plant environment. Simple,
rapid, and nondestructive methods are needed to indicate daily and hourly rates
of growth under field conditions. Because plant carbon balance is one possible
approach to this problem, CO2 gas exchange parameters were measured on Beta vul-
garis leaves of field-grown plants to learn whether or not they might signal the
onset of nitrogen and P stresses. The sugarbeets were grown on field plots of
Portneuf silt loam soil and allowed to develop severe N and P stresses. Carbon
dioxide exchange and stomatal resistance of intact plant leaves were measured with
small leaf chambers .during 1 minute periods. Leaf water potentials were also
measured in the field with a hydraulic press. The CO2 compensation points, dark
respiration, and osmotic pressures of excised leaf tissue were measured in the
laboratory by standard methods. Photosynthesis per unit leaf area was reduced in
advanced stages of N deficiency; however, none of the measurements satisfactorily
indicated the onset of N or P stress because of heterogeneity between leaves.
77:07B-015
MISCIBLE DISPLACEMENT OF NITRATE AND CHLORIDE UNDER FIELD CONDITIONS,
Misra, C-, and Mishra, B.K,
Orissa University of Agriculture and Technology, Dryland Agricultural Research
Project, Bhubaneswar-751003, India.
Soil Science Society of America Journal, Vol. 41, No, 3, p 496-499, May-June, 1977.
2 fig, 1 tab, 13 ref, 5 equ .
Descriptors: Nitrates, Nutrients, Fertilization, Fertilizers, Leaching, Soil
water. Soil water movement, Irrigation effects, Denitrif ication,
In an attempt to develop the capability for predicting the reduction loss of
N03(-)N during leaching of nitrate fertilizers in an Oxisol field profile, a 2-cm
' - laced throuh a
N03(-)N during leacng o nra
pulL'of CaCNOSU solution containing 304 ppm of N03 (-)N was di laced through a
^
^
order sink term.
MEASUREMENT OF SOIL GASEOUS DIFFUSION COEFFICIENTS BY A TRANSIENT-STATE METHOD WITH
A TIME-DEPENDENT SURFACE CONDITION,
Rolston, D.E., and Brown, B.D.
249
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California University, Department of Land, Air and Water Resources, Davis,
California 95616.
Soil Science Society of America Journal, Vol. 41,.No. 3, p 499-505, May-June,
1977. 8 fig, 2 tab, 11 ref, 7 equ.
Descriptors: Soils, Soil investigations, Soil properties, Soil gases, Denitrifi-
cation, Nitrogen, Soil profiles.
Precise measurement of the gaseous diffusion coefficient in soils is necessary for
calculating the flux of gas resulting from soil respiration, denitrification, or
fumigation. Gaseous diffusion coefficients of soil columns and a field soil were
determined by fitting a solution of the transient-state diffusion equation for^a
time-dependent surface condition to measured N2 concentration profiles. The time-
dependent surface condition was experimentally imposed by pumping argon at a con-
stant rate into a chamber placed within the soil and on the soil surface. The
argon and air mixture exited the chamber through several exit ports. The N2 con-
centration at the soil surface and within the soil profile was determined several
times within a 5-hour period after initiation of the argon flow. A solution of
the diffusion equation for a nonconstant initial condition can also be used for
determining the diffusion coefficient for cases where the initial gas concentration
is not constant with depth. Diffusion coefficients for a field soil determined
from the transient-state solutions compared favorably with those determined from
laboratory measurements on undisturbed soil cores and field measurements of C02
flux.
77:078-017
THE ASSESSMENT OF PLANT-AVAILABLE CADMIUM IN SOILS,
Symeonides, C., and McRae, S.G,
Wye College (London University), Department of Physical Sciences, Ashford, Kent,
England.
Journal of Environmental Quality, Vol. 6, No, 2, p 120-123, April-June, 1977,
2 fig, 4 tab, 35 ref.
Descriptors: Cadmium, Heavy metals, Soils, Soil investigations, Water quality,
Pollution, Crop response.
A study has been made of the amounts of cadmium recovered by a variety of reagents
and extraction procedures from soils to which Cd has been added, Correlation of
these results with the Cd content of radish plants grown in these soils has shown
that the most sensitive of several possible indices to Cd uptake by plants is the
amount extracted by a 1-hour shaking with IN ammonium nitrate solution at a soil/
solution ratio of 1:10 (wt/vol). The greater efficiency of this extractant com-
pared with other proposed extractants is ascribed to the system reflecting the
natural pH of the soil which has a marked effect on cadmium availability to plants.
77:078-018
DETERMINATION OF ORTHOPHOSPHATE IN AQUEOUS SOLUTIONS CONTAINING LABILE ORGANIC
AND INORGANIC PHOSPHORUS COMPOUNDS,
Dick, W.A., and Tabatabai, M.A,
Iowa University, Department of Agronomy, Ames, Iowa 50011,
Journal of Environmental Quality, Vol. 6r No, 1, p 82-85, January-March, 1977.
4 fig, 3 tab, 16 ref.
Descriptors: Sampling, Water quality, Water quality control, Phosphorus, Laboratory
tests, Fertilizers, Nutrients.
A simple and precise colorimetric method of determining orthophosphate in aqueous
solutions containing labile organic and inorganic P compounds is described. It
involves a rapid formation of molybdenum blue color by the reaction of orthophos-
phate with molybdate ions in the presence of ascorbic acid-trichloroacetic acid
and citrate-arsenite reagents and complexation of the excess molybdate ions to
prevent further formation of blue color from the phosphate derived from hydrolysis
of the acid-labile P compounds. The color is stable up to 24 hours. The method
is sensitive and accurate, and it permits determination of microgram quantities of
orthophosphate in samples containing large amounts of acid-labile P compounds.
Tests with a wide range of condensed phosphate and organic phosphate compounds
showed that none of the P compounds studied interfered with this method. Results
by this method are compared with those obtained by the method of Murphy and Riley.
250
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77:07B-019
A SELF-PROPELLED HIGH-CLEARANCE SOIL CORING MACHINE,
Bausch, W., Onken, A.B., Wendt, C.W., and Wilke, O.C.
Texas A and M University, Texas Agricultural Experiment Station, Agricultural
Research and Extension Center, Lubbock, Texas.
Agronomy Journal, Vol. 69, No. 1, p 122-124, January-February, 1977. 4 fig, 1 tab,
Descriptors: Sampling, Crop production, Soil investigations, Soils, Soil tests
Soil profiles. Soil properties. '
Mechanical soil sampling equipment currently available is suitable for sampling
prior to crop establishment or in low grouping crops but cannot be used without
plant damage in some tall crops. A self-propelled high-clearance soil coring
machine was designed and constructed to obtain soil samples in a tall standing
crop at a range of lateral as well as vertical distances. The sampler is hydrauli-
cally operated and has vertical pressure and rotary drilling capabilities. This
equipment has a lateral travel span of 152 cm and the capability of coring to a
depth of 9 m with the mast in any lateral position on the track. Two operators
can use the sampler without difficulty; however, three operators are desirable if
a large number of samples are to be taken. As many as eighty 30-cm increment soil
samples have been taken per hour when sampling a moist sandy soil to a depth of
2 m.
77:07B-020
SOIL NITRATE-NITROGEN DETERMINED BY CORING AND SOLUTION EXTRACTION TECHNIQUES,
Alberts, E.E., Burwell, R.E., and Schuman, G.E,
United States Department of Agriculture-Agricultural Research Service, West
Lafayette, Indiana.
Soil Science Society of America Journal, Vol, 41, No. 1, p 90*-92, January-February.-
1977. 1 fig, 1 tab, 13 ref.
Descriptors: Nitrates, Nitrogen, Sampling, Soil profiles, Soil tests, Iowa,
Leaching.
Soil-coring and solution-extraction sampling techniques were compared for deter-
mining the content of NO3(-)N in the soil profile of a Monona s±lt loam in south-
western Iowa. The NO3(-)N content of the 3.05-m profile, determined by solution
extraction, was 28% lower in 1972, 8% higher in 1973, and 13% lower in 1974 than
that determined by soil coring. The profile difference in N03(-)N content between
the two sampling techniques was insignificant in 1973 and 1974 but was highly
significant (1%) in 1972.
77:07B-021
DIGITAL ELECTRONIC MEASUREMENT AND RECORDING OF IRRIGATION FIELD WATER DEPTHS,
Dawes, W.H., Casey, M.R., Scharplaz, J.D., and Manges, H,L,
ICE Corporation, Manhattan, Kansas 66502.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-3.
1 fig.
Descriptors: Furrow irrigation, Water table, Sampling, Irrigation practices,
Irrigation effects.
This presentation describes a system for measuring water depths at twelve locations
in a three-furrow irrigation field with capacitance type level sensors. The data
from the sensors is recorded on a cassette tape at one or five minute intervals.
The system is battery operated. Methods for retrieving data from a cassette
tape are discussed.
77:07B-022
MARINE DYNAMICS AND ITS EFFECT
Mero, T., and Appall, G.
Test and Evaluation Laboratory
ON
CURRENT MEASURING TRANSDUCERS,
National Oceanic and
Proceedings of the Symposium on Flow Measurement in Open Channe.
duits, Gaithersburg, Maryland, p 109-121, February 23-25, 197/.
3 fig, 3
Con-
tab,
3 ref.
251
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Descriptors: Velocity, Flow measurement, Currents (water), Turbulence, Turbulent
flow, Dynamics.
A growing interest in measuring current velocities in coastal zone and estuaries
prompted the creation of a Dynamic Analysis Program at T&EL (formerly NOIC). The
dynamics of near-shore current flows are more severe than that of the deep ocean.
Therefore, it is important to qualify the performance of current measuring trans-
ducers in a dynamic environment. A study was contracted to determine what scales
and intensities of turbulence exist in the near-shore environment. The major effort
of the study is concerned with turbulence from 1 to 20 Hz and scales up to 30 cm.
Tests are being conducted to determine the response characteristics of several
current measuring transducers including both rotor and electromagnetic instruments.
These tests include grid-produced turbulence measurements as well as simulated
mooring-line dynamics' tests. Measurements have revealed several transducers that
have 10 to 20% sensitivity increases when turbulence intensities of 6 to 12% are
present. This paper contains a description of turbulence that exists in the marine
environment along with dynamic response characteristics of several current measuring
transducers.
77:078-023
A NEW DIELECTRIC SOIL MOISTURE METER FOR FIELD MEASUREMENT OF SOIL MOISTURE,
Kuraz, E.V., and Matousek, J.
Technical University, Department of Irrigation and Drainage, Karlova nam, 3,
Praha 2.
International Commission on Irrigation and Drainage, Vol. 26, No. 1, p 76-79,
January 1977. 3 fig, 5 ref.
Descriptors: Soil moisture, Soil water, Soil properties, Bulk density. Sampling.
A new apparatus for the soil moisture measurement in field conditions by a di-
electric method has been developed. The arrangement is based on the principle
of the capacitancefrequency converter. With a good operating reliability and
temperature stability, a miniaturization of the device has been reached. The
apparatus works in the whole range of moisture content, the measurement is
also influenced by the change of bulk density. The temperature change is ir-
relevant and the sensitivity to the change of the chemical composition is low.
The measuring procedure is very simple, the reading is possible either on the
scale, or a registering apparatus can be connected. For each soil a calibration
curve has to be determined.
77:07B-024
ERRORS IN FLOW MEASUREMENT AND THEIR IMPORTANCE IN INFILTRATION/INFLOW ANALYSIS,
Guthrie, D.L., Washington, D.R., and Vincenty, C.
Environmental Quality Systems, Incorporated, Rockville, Maryland.
Proceedings of the Symposium on Flow Measurement in Open Channels and Closed
Conduits, Gaithersburg, Maryland, p 173-200, February 23-25, 1977. 7 fig, 2 tab,
10 ref, 2 equ.
Descriptors: Flow measurement, Infiltration, Weirs, Flumes, Water measurement,
Seepage.
Several common flow-measurement devices including the weir, Parshall flume, and
scow were used in field studies of infiltration/inflow in Puerto Rico. Mathemati-
cal determinations of infiltration/inflow were made by calculating the hydraulic
gradient, the height of water in the sewer, and the velocity head loss. Both of
these instrumental and physical-mathematical methods for flow determination are
reviewed, stressing the advantages and disadvantages of each, their sources of
error, and methods used to resolve that error, wherever possible,
77 :07B-025
COMPENSATING FOR CONSTRUCTION ERRORS IN CRITICAL-FLOW FLUMES AND BROAD-CRESTED
WEIRS,
Replogle, J.A.
United States Department of Agriculture, Agricultural Research Service, United
States Water Conservation Laboratory, 4331 East Broadway, Phoenix, Arizona 85040.
Proceedings of the Symposium on Flow Measurement in Open Channels and Closed
Conduits, Gaithersburg, Maryland, p 201-218, February 23-25, 1977. 5 fig, 1 tab,
8 ref, 1 equ.
232
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Descriptors: Flow measurement, Flumes, Weirs, Open channel flow. Water measure-
^?K°ai~*1C??^UKeS Snd broad~crested weirs can now be routinely and accurately
calibrated (±2%) by computer techniques over a wide range of flow rates and flume
cross sections, including trapezoidal and complex shapes. This ability permits
detailed compensation for errors introduced by construction anomalies. Proce-
dures were developed and used on a series of primary devices in irrigation canals,
including trapezoidal flumes and broad-crested weirs, which identified construction
errors and accurately related a readout mechanism to the primary device, as con-
structed, so that the original intended accuracy could be restored.
77:076-026
INSTRUMENT ERRORS IN OPEN CHANNEL FLOW MEASUREMENT SYSTEMS
Grant, D.M.
Instrumentation Specialties Company, Post Office Box 5437, Lincoln, Nebraska 68505.
Proceedings of the Symposium on Flow Measurement in Open Channels and Closed Con-
duits, Gaithersburg, Maryland, p 91-103, February 23-25, 1977. 9 ref.
Descriptors: Flow measurement, Open channels, Open channel flow, Instruments.
Certain aspects of open channel flow measurement systems are briefly discussed,
including primary and secondary measuring devices. The two functions of a secondary
measuring device (open channel flow meter) are discussed i level measurement and
level-to-flow rate conversion. Some of the common methodologies used to accomplish
each of the two functions of a secondary device are described, and the possible
sources and magnitudes of errors associated with each of these methodologies are
analyzed. Level measurement methods discussed are: float, electrical, ultrasonic,
bubbler, and dipping probe. Level-to-flow rate conversion methods discussed are:
mechanical cam, electronic analog function generator, electronic memory device,
and opto-electronic function generator, In the interest of promoting a uniformity
of specifications, a standard general format for open channel flow meters is pro-
posed.
77:078-027
NUMERICAL MODELING OF TWO-DIMENSIONAL FLUMES,
Davis, R.W.
Mechanics Division, National Bureau of Standards.
Proceedings of the Symposium on Flow Measurement in Open Channels and Closed
Conduits, Gaithersburg, Maryland, p 219-242, February 23-25, 1977. 12 fig, 2
tab, 10 ref, 9 equ,
Descriptors: Water measurement, Flow measurement, Flumes, Open channel flow,
Hydraulics, Model studies, Weirs.
Flumes are commonly used devices for the measurement of open-channel flow rates,
Their range of operation has been limited, however, because, outside of experimen-
tally calibrating each configuration used, one has had to resort to one-dimensional
theory for flow rate determination. This theory is restricted to fairly low values
of upstream-head to crest-length ratio, as well as to almost level flumes with a
resonably uniform incoming velocity profile and nonconverging sidewalls. The present
study is concerned with extending the operational range of a particular type of
flume (the two-dimensional version of the Palmer-Bowlus flume} into areas where
one-dimensional theory loses its validity. The determination of the head^ischarge
relationship for this flume is done numerically by use of the SOLA finite difference
routine for two-dimensional free-surface flows. Effects of changes in flume
geometry, channel slope, and upstream velocity profile are investigated. The
numerical results are verified experimentally,
THE0D^I°GN OF OPEN CHANNEL ACOUSTIC FLOWMETERS FOR SPECIFIED ACCURACY, SOURCES OF
ERROR AND CALIBRATION TEST RESULTS ,
Sn'Research^quipment, Incorporated, Accusonic Division, Falmouth, Massachusetts
Proceedings of the Symposium on Flow Measurements in Open Channels and Closed
Conduits, Gaithersburg, Maryland, p 243-266, February zj n,
253
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Descriptors: Flow measurement, Water measurement, Velocity, Flow rate.
The design of open channel acoustic flowmeters is more difficult than the design
of pipeline flowmeters because of errors introduced by the free surface, as well
as because the open channel environment is usually more susceptible to attenuation
and multipath conditions which can inject large errors unless special signal
recognition and filtering techniques are employed. The sources of error in open
channel acoustic flowmeters are tabulated and discussed.
77:07B-029
VALIDATION OF USE OF DYE-DILUTION METHOD FOR FLOW MEASUREMENT IN LARGE OPEN AND
CLOSED CHANNEL FLOWS,
Morgan, W.H., Kempf, D., and Phillips, R.E.
Peerless Pump, An Indian Head Company, Montebello, California 90640.
Proceedings of the Symposium on Flow Measurement in Open Channels and Closed
Conduits, Gaithersburg, Maryland, p 361-394, February 23-25, 1977. 12 fig, 4 tab,
13 ref, 1 append.
Descriptors: Flow measurement, Water measurement, Open channel flow, Pipe flow.
Pipelines, Tracers, Flumes, Calibrations,
The use of water soluable tracers for determining flow rates of rivers and streams
has been practiced for several decades, both in the United States and abroad. During
the last 15 years the economical availability of water soluable dyes, coupled with
the considerable technical improvement in fluorometry equipment, has made feasible
the use of dye-dilution methods for in situ calibration and other flow measurement
devices.
77:07B-030
CALCULATORS IN TIMER-COUNTERS FOR CURRENT METERS,
Kormilo, S.R.
Papuea New Guinea University of Technology, Department of Electrical and Communi-
cations Engineering, Lae (New Guinea),
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY9, Proceedings Paper 13230, p 1031-1036, September 1977, 2 fig, 1 ref,
2 append.
Descriptors: *Instrumentation, *Current meters, *Equipment, Electronics, Laboratory
tests. Flow, Measurement, Time, Timing, Engineering, Electrical engineering. Hydro-
logy.
An accurate, compact, low-cost, calculator-based electronic timers-counter for cur-
rent meters was constructed and laboratory tested. Electronic calculators often
offer an economically attractive alternative to both electromechanical and other
forms of electronic counters. The modification of calculators so that they can
act as timer-counters was described in general terms. A summary of the results of
tests to determine the effect of temperature and voltage variations on the timing
accuracy of a prototype electronic timer-counter was given. Laboratory tests also
were performed which compared the prototype to two different electromechanical
counters in operation. The tests indicated that, with a few minor changes, the
electronic timer-counter would provide many advantages over the electromechanical
counters.
77:078-031
A MECHANICALLY CONTROLLED VARIABLE RATE LEACHING DEVICE,
Holmgren, G.G.S., Juve, R,L., and Geschwender, R.C,
National Soil Survey Laboratory, Lincoln, Nebraska 68508.
Soil Science Society of America Journal, Vol. 41, No, 6, p 1207-1208, December 1977.
1 fig, 1 tab.
Descriptors: Leaching, Sampling, Laboratory studies, Cation exchange.
Twenty-four leaching tubes attached to 60-ml plastic syringes are mounted on the
periphery of three vertically aligned slotted discs 45 cm in diameter. The plungers
are withdrawn at a controlled rate by a variable speed screw jack that separates the
two lower discs holding the plungers and syringe barrels, respectively. Leaching
time can be varied from 15 min, to 12 hours or more. The final volume of extract
254
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is determined by weighing the syringes. Precision of ammonium acetate CEC and
by this procedure with 2.5 grams of soil and fo-ml extract
matoh
of soil anf loo ^lCO?Parf le.man^X meth°d USlng Vacuum ^traction with 5 grams
time in half extract. Thls apparatus has also cut required operator
77:078-032
CORRECTION FOR DISSOLVED NITROUS OXIDE IN NITROGEN STUDIES
Moraghan, J.T. , and Buresh, R. '
North Dakota State University, Department of Soils, Fargo, North Dakota
Soil Science Society of America Journal, Vol. 41, No. 6, p 1201-1202 November-
December, 1977. 1 fig, 2 tab, 6 ref.
Descriptors: Nitrification, Denitrif ication, Nitrogen, Temperature, Sampling.
Rapid methods for the accurate determination of N20 in atmospheres of closed
incubation flasks are now available. However, serious errors in measuring total
N20 within a closed system may arise if dissolved N20 is not considered. Temper-
ature and the ratio of solution volume to atmosphere volume are important factors
determining the magnitude of errors resulting from this cause. A simple formula
for calculating dissolved N20 based on solution and atmosphere volumes, the mass
of N20 in the gaseous phase, and published solubility data for N20 in water is
presented. If the chemical composition of the solution phase is likely to
influence solubility coefficients, these values can be experimentally determined
using a described technique.
77 :07B-033
DESIGN AND TEST OF A FIELD SAMPLER FOR AMMONIA" VOLATILIZATION,
Kissel, D.E., Brewer, H.L. , and Arkin, G.F.
United States Department of Agriculture, Agricultural Research Service, Texas
Agricultural Experiment Station, Post Office Box 748, Temple, Texas 76501.
Soil Science Society of America Journal, Vol. 41, No. 6, p 1133-1138, November ^-
December, 1977. 9 fig, 1 tab, 12 ref.
Descriptors: Ammonia, Fertilizers, Data collection, Sampling, Nitrogen, Fertili-
zation.
A system is needed to measure ammonia volatilization from N fertilizer applied
under field conditions. This study was undertaken to develop a device for making
these measurements and still maintain a field environment. The basic system
developed consists of a vacuum pump, a chemical trap to capture ammonia, and the
volatilization chamber.
77:078-034
DENITRIFYING BACTERIA CAN BE ENUMERATED IN NITRITE BROTH,
Volz, M.G.
Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504.
Soil Science Society of America Journal, Vol. 41, No. 3, p 549-551, May-June,
1977. 2 tab, 20 ref.
Descriptors: Denitrif ication, Bacteria, Nitrites, Laboratory tests.
Denitrifying- and N03- reducing bacteria in air dry, moist and organic matter
amended Yalesville fsl, lake water, and in both effluent and drainage field
soil from a septic tank system were enumerated using Difco nutrient broth, which
contained either or both N03- and N02- and was incubated anaerobically Most
probable numbers (MPN) of denitrifiers were always less than those of N03-
reducers in the same sample, and constituted from 0.02% to 70% of bacteria
capable of aerobic growth on yeast extract agar.
SAMPLING DISTRIBUTION OF NITRATES IN IRRIGATED FIELDS,
12 ref, 8 equ.
255
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Descriptors: Sampling, Nitrates, Irrigation, Irrigation effects, Irrigation
practices, Colorado, Nebraska, Laboratory tests, Fertilizers, Fertilization.
The object of this study was to determine the components of variability encountered
in sampling farmers' fields for soil nitrates. This information is required for
formulating recommendations for sampling plan and intensity. Twenty-four irrigated
farm fields in northeastern Colorado and Western Nebraska were sampled on 61 x 61
m grids. One soil core was taken in 30-cm increments from each grid to a depth of
120 cm. Duplicate cores were obtained from each third grid to allow determination
of within grid variability. The laboratory-induced variability was also estimated.
The results indicated that within and among grid standard deviations increased as
the means increased. The standard errors of laboratory determinations (sub-
sampling plus analytical errors) also increased as the means increased,
77:07B-036
A PORTABLE CHAMBER FOR RAPID EVAPOTRANSPIRATION MEASUREMENTS ON FIELD PLOTS,
Reicosky, D.C., and Peters, D.B,
South Carolina Agricultural Experiment Station, Florence, South Carolina.
Agronomy Journal, Vol. 69, No. 4, p 729, 732, July-August, 1977, 4 fig, 6 ref.
Descriptors: Sampling, Evapotranspiration, Crop production, Scheduling,
Irrigation efficiency. Soil water, Soil moisture, Temperature,
The increased importance of water-use efficiency in agricultural production has
prompted the need for new techniques to measure evapotranspiration (ET) on
field plots to evaluate the effects of new soil and water management practices
of an inexpensive, portable chamber for rapid field measurement of ET. This
chamber was constructed from aluminum conduit covered with Mylar film and
mounted on a farm tractor for portability. The air within the chamber was
mixed constantly with four strategically located fans. The ET rate was calculated
from the air and wet-bulb temperatures of a thermistor psyc'hrometer before the
chamber was lowered on the plot and 1 minute later. The psychrometer's accuracy
was checked by measuring the transpiration from a solution-absorption system that
accurately measured the change in solution level using an LVDT-float system. When
microlimatological conditions were changing slowly, transpiration was assumed to be
equal to the absorption. The high correlation between measured absorption and
transpiration rates indicated reasonable accuracy. The chamber*s accuracy and
rapidity of the measurement, portability, and relatively low cost makes it a
useful tool in measuring ET under field conditions.
77:O7B-037
DETERMINING CATION EXCHANGE CAPACITY; A NEW PROCEDURE FOR CALCAREOUS AND
GYPSIFEROUS SOILS,
Polemic, M., and Rhoades, J.D.
United States Salinity Laboratory, United States Department of Agriculture,
Agricultural Research Service, Riverside, California 92502.
Soil Science Society of America Journal, Vol. 41, No. 3, p 524^-528, May«-June,
1977. 2 fig, 2 tab, 23 ref.
Descriptors: Cation exchange, Soils, Soil tests, Soil investigation, Soil
properties.
A new, two-step procedure is presented for determining the cation exchange
capacity of calcareous and gypsiferous soils. The method eliminated most of the
errors inherent in conventional methods. The cation exchange sites are saturated
with sodium by four successive "equilibrations" of the soil (4-5 grams) with
33-ml increments of a pH 8.2, 60% ethanol solution of 0.4N NaO Ac - 0.1N NaCl
(saturating solution), The saturated sample then is extracted with three 33-ml
increments of l.ON, pH 7 magnesium nitrate. Total sodium (Nat) and chloride
(Clt) are subsequently determined in the extracted solution. Chloride (Clt)
is determined so that the soluble sodium (Nasol), from the excess saturating
solution carried over from the saturation step to the extraction step, may be
deducted from the total sodium (Nat) to obtain exchangeable sodium (Naexch), which
is equivalent to the CEC. Thus, CEC = Naexch = (Nat - Nasol) = Nat - (Clt(Na/Cl)
saturating solution) where (Na/Cl) saturating solution is the ratio of Na to Cl
in the saturating solution.
256
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SECTION XXIV
RESOURCES DATA
EVALUATION, PROCESSING AND PUBLICATION (GROUP 07B)
77:07C-001
PREDICTION OF MINERAL QUALITY OF IRRIGATION RETURN FLOW: VOLUME IV- DATA ANALYSIS
UTILITY PROGRAMS,
Bureau of Reclamation, Engineering and Research Center, Denver, Colorado 80225.
Publication No. EPA-600/2-77-179d, August 1977. 222 p, 1 ref.
(See 77:05G-030)
77:07C-002
EXPERIMENTAL EVALUATION OF TWO INFILTRATION EQUATIONS,
Idike, F., Larson, C.L., Slack, D.C., and Young, R.A.
Minnesota University, Department of Agricultural Engineering, Saint Paul, Minnesota.
Presented at the 1977 Winter Meeting of the American Society of Agricultural Engineers,
December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-21. 6 fig, 4 tab,
21 ref, 6 equ.
Descriptors: Infiltration, Soil water, Soil moisture, Soil water movement, Runoff,
Equations.
Infiltration from constant application rates as predicted by the Holtan equation
and the Mein and Larson equation was compared to values determined experimentally.
Both equations did a good job of predicting infiltration during latter and middle
portions of the experimental runs. The Mein and Larson equation did a good job
of predicting time to start of runoff, while the Holtan equation generally under-
predicted infiltration during initial stages of the runs.
257
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SECTION XXV
ENGINEERING WORKS
STRUCTURES (GROUP 08A)
77:08A-001
A PROPOSED TECHNIQUE FOR TESTING AND EVALUATION OF HARDENED IRRIGATION DITCH
CONCRETE,
Hess, J.D.
Darco Engineering International, El Centre, California,
Presented at the 1977 Annual Meeting of the American Society of Agricultural
Engineers, June 26-29, 1977, Raleigh, North Carolina, North Carolina State
University, p 1-10. 4 fig, 1 tab.
Descriptors: Irrigation, Irrigation systems, Concrete, Sampling,. Canals, Canal
linings.
A new testing technique is presented for the strength evaluation of hardened
irrigation ditch concrete. The test procedure eliminates the need for evaluating
in-service strength characteristics based solely upon conventional 6 inch by 12
inch cylinder tests or tests on small cores or prisms. No L/D corrections are
required.
253
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SECTION XXVI
ENGINEERING WORKS
HYDRAULICS (GROUP 08B)
77:088-001
HYDRAULIC JUMPS AND WAVES AT ABRUPT DROPS ,
Rajaratnam, N. , and Ortiz, N,V.
Alberta University, Department of Civil Engineering, Edmonton, Alberta, Canada.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY4, Proceedings Paper 12869, p 381-394, April 1977. 14 fig, 2 tab, 11 ref,
2 append .
Descriptors: *Drops (structures), *Flow, *Hydraulic jump, Open channel flow,
Open channels, Shear stress, Turbulent flow, Waves (water), Tailwater, Hydraulics,
Experimental results on the structure of the mean flow in B^-jumps and waves formed
at abrupt drops in open channels for a wide range of the supercritical Froude
number and relative drop height were presented. In the B-jump, the supercritical
stream undergoes diffusion; firstly as a curved free jet sandwiched between the
captive eddy on the bottom and the surface roller on the top, and secondly as a
reattached plane wall jet with the surface roller on its top. The bed shear stress
in the downstream channel was measured and well correlated along with the variation
of the maximum velocity. In the wave, it was found: (1) that the supercritical
stream is deflected by the tailwater back-pressure, and (2) that the deflected
stream behaves like a curved surface jet until it plunges into the tailwater. The
decay of the maximum velocity in the wave was found to be generally faster than
that in the classical jump and the B-jump.
77:08B-002
EFFECT OF BRANCH SPACING ON LOSSES FOR DIVIDING FLOW,
Becker, G.E., Nystrom, J,B., and Qureshi, N.A,
Worcester Polytechnic Institute, Department of Civil Engineering, Worcester,
Massachusetts .
Journal of the Hydraulic Division, American Society of Civil Engineers, Vol , 103,
No. HY3, Proceedings Paper 12791, p 265-279, March 1977. 10 fig, 15 ref, 2 append.
Descriptors: *Head loss, *Discharge (water), *Hydraulics, *Pipe flow, laboratory
tests, Hydraulics, Energy equation, Discharge coefficient, Friction, Dimensional
analysis, Equations.
Tests were conducted to evaluate the effects of port spacing on head loss and
charge coefficients for dividing manifold flow. A branch geometry typical of an
actual diffuser design was used, and the branch-to-main-pipe-diameter ratio and
the relative spacing between branches were varied by increments. Evaluation of the
test data for dividing flow indicated that the asymmetry of the velocity distribu-
tion in the main pipe downstream of a branch increased with decreasing branch
spacing; the form loss coefficient for through-flow in the main pipe increased with
decreasing relative branch spacing; and the branch discharge coefficient increased
with decreasing relative branch spacing. Although a particular geometry ^was used
in the investigation, basic trends and percentage changes in the coefficients with
the branch spacing may be generally applicable,
77:08B-003
FREE FLOW IMMEDIATELY BELOW SLUICE GATES ,
A^ertfuniversity, Department of Civil Engineering, «on Alberta,. Canada
Journal of the Hydraulic Division, American Society of Civil Engineers,. Vol 103,
No. HY4, Proceedings Paper 12867, p 345-351, April 1977. 7 fig, 1 tab, 9 ref,
2 append .
259
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Descriptors: *Boundary layers, *Flow, *Sluice gate, Gate control, Gates, Open
channel flow, Sluices, Hydraulics, Laboratory tests. Channels, Profiles, Pressure.
Based on the results of an experimental study, it was found that the water surface
profiles immediately below sluice gates in rectangular channels are similar. The
coefficient of contraction was found to be larger than the theoretically predicted
value, and it is not possible to attribute this difference to boundary layer effects
alone. The pressure field in the converging flow was measured, and the dimension-
less excess pressure on the bed was correlated with the dimensionless longitudinal
distance from the gate.
77:08B-004
TWO-DIMENSIONAL SEARCHES FOR HIGH-YIELD WELL SITES,
Turk, G.
Ground Water, Vol. 15, No. 4, p 269-275, July-August, 1977. 6 fig, 2 tab, 8 ref.
Descriptors: *Well spacing, *Drilling, *Exploration, Test wells, Costs, Aquifer
characteristics, Transmissivity, Optimization, Sampling, Depth, Water yield,
Analytical techniques.
In areas where bedrock is irregular, greater saturation thickness of aquifer will
associate with the depression in the bedrock formation. Wells located upon the
depressions can yield significantly higher amounts of water. Hence, finding the
bottom of depression the area will be of interest, and this can be facilitated by
drilling test holes. The test holes can be drilled at the nodes of a regular
grid; however, more efficient search techniques are available, Fibonacci search
in one dimension was proposed recently, and potential saving in drilling cost was
demonstrated. But the problem is essentially two-dimensional in nature. This
paper described some two-dimensional search procedures and showed that potential
saving in drilling cost can be dramatic.
77:086-005
PROPORTIONAL WEIRS AS VELOCITY CONTROLLING DEVICES,
Rao, L., Rao, N.S., and Chandrasekaran, D.
Indian Institute of Science, Department of Civil Engineering, Bangalore.
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY6, Proceedings Paper 13016, p 633-648, June 1977. 5 fig, 2 tab, 10 ref,
2 append.
Descriptors: *Weirs, *Velocity, *Canals, Discharge coefficient, Sedimentation,
Sediment control, Orifices, Settling basins, Settling velocity, Hydraulics.
Of the many factors that govern the settling phenomenon, the flow velocity in the
settling tanks can be controlled favorably by fixing suitably designed weirs at
the outlets of the tanks. The velocity at the bottom should not dislodge the
particles that have already settled. The requirements might be met by velocities
which are controlled to be constant with respect to the depth of flow, or by
velocities which reduce linearly with increasing depth or velocities that vary
inversely with the depth. To achieve these types of velocity control, new pro-
portional wiers were designed. Very near to the outlet of the tank, over a small
length, the flow was found to be turbulent and noncompliant with the expected
type of velocity control. This small length of the disturbance may be provided
over and above the theoretical settling length of the tank for efficient sedimen-
tation.
77:08B-006
COMPUTERIZED DESIGN AND ANALYSIS OF SPRINKLER IRRIGATION SYSTEMS,
Hedstrom, W.E., and Bevilacqua, D.P.
Maine University at Orono, Department of Agricultural Engineering, Orono, Maine
04473.
Presented at the 1977 Winter Meeting of the American Society of Agricultural
Engineers, December 13-16, 1977, Palmer House Hotel, Chicago, Illinois, p 1-13,
9 ref, 2 equ.
260
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Descriptors: Sprinkler irrigation, Irrigation, Irrigation design. Computer pro-
grams. Economics, Hydraulics, Hydraulic design. Computer pro
The elements of the sprinkler irrigation design procedure which may be computerized
are discussed. _These include hydraulic analysis, application rate analyst and In
economic analysis as well as other applications. The conditions under which use
of the computer is most worthwhile include design of solid-set systems on ir-
regularly-shaped, steep fields.
77:08B-007
PORTABLE, ADJUSTABLE, FLOW-MEASURING FLUME FOR SMALL CANALS,
Replogle, J.A.
Agricultural Research Service, Water Conservation Lab, Phoenix, Arizona.
Transactions of the American Society of Agricultural Engineers, Vol 20' No 5
p 928-933, September-October, 1977. 5 fig, 5 ref, 2 append. ' ' '
Descriptors: *Flumes, *Flow measurement, *Canals, Channels, Instrumentation,
Hydraulics, On-site investigations, Measurement, Flow, Design,
A portable, field-site, survey flume was constructed and used to verify placement
and design of permanent metering flumes. The portable system consisted of a
trapezoidal throat that can be raised and lowered in a flowing field ditch to es-
tablish limits of free-flow operation and backwater effects on upstream structures.
Mechanical solutions to problems of maintaining gage-zero on a movable-throated
flume, stilling-well readout, and movable seals between ditch and flume, were pre^
sented. A family of concrete throat sections differing only in height of instal-
lation from the canal floor, were recommended for the permanent installations.
Flows between about 0.5 cfs (.0.01 cu m) and 25 cfs (0.7 ,cu m) can be measured with
the portable system. Satisfactory operation can be achieved with less than 4-in
(10-cm) head loss to the canal system. Permanent structures can be installed with
high assurance that they will operate as intended, will be convenient enough to be
used routinely, and will be rugged enough to remain reliable and accurate, well
within the + or - 5% tolerance usually ascribed to field installations.
77:08B-008
EFFECT OF OPENINGS ON INFLOW INTO CORRUGATED DRAINS,
Bravo, N.J., and Schwab, G.O.
Ohio State University, Department of Agricultural Engineering, Columbus, Ohio.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No. lf
p 100-104, January-February, 1977. 6 fig, 3 tab, 11 ref.
Descriptors: *Drains, *Inflow, *Analog models, 'Orifices, Plastic pipes, Mathemati-
cal models, Saturated flow, Laplaces equation, Boundaries (.surfaces), Groundwater
potential, Hydraulic conductivity, Flow, Soil water movement.
The relative effectiveness of the openings in corrugated plastic drains as influenced
by the presence of soil within the corrugations and within the openings themselves
was evaluated from the standpoint of water inflow for saturated conditions in a
homogeneous, isotropic soil. Electrical analog models provided empirical estimates
of the relative flow into drain openings as well as the boundary conditions for
mathematical models. Three-dimensional mathematical models were based on Laplace's
equation with appropriate boundary conditions. After agreement between the analog
and mathematical models was established for simple configurations, inflow for the
more complicated cases was measured with electric analog models,
77:088-009
SIMULATION OF IMPOUNDMENT TERRACE HYDRAULICS,
Rochester, E.W., and Busch, C.D. . ,,,,=m=
Auburn University, Department of Agricultural Engineering, Auburn Alabama.
Transactions of the American Society of Agricultural Engineers, Vol. 20, No, 1,
p 76-84, January-February, 1977. 5 fig, 8 ref.
Descriptors: 'Terracing, 'Impoundments, 'Model studies, ^hematical models,
Inflow, Discharge (water), Depth, Water levels, Computer models, Pipes, Pipe
flow, Drainage, Hydraulics, Agriculture, Simulation analysis.
261
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A digital simulation predicts flow conditions associated with a series of two
"impoundment terraces. The simulation routes inflowing water through the im-
poundments and associated discharge pipes. Results of the simulation include
depths of the water in each impoundment, flow rates through each discharge pipe,
and hydraulic head at the junction of the pipes.
77:088-010
DESIGN OF DRIP IRRIGATION LINES WITH VARYING PIPE SIZES,
Wu, I-P-, and Gitlin, H.M.
Hawaii University, Department of Agricultural Engineering, Honolulu, Hawaii.
Journal of the Irrigation and Drainage Division, Vol. 103, No, IR4, p 499-503,
December 1977. 2 fig, 5 ref, 9 equ. 1 append.
Descriptors: Irrigation design, Irrigation efficiency, Hydraulics, Irrigation
methods, Hydraulic design, Design, Irrigation engineering.
Most drip irrigation laterals and submains are designed for a single pipe size.
The energy gradient line for a lateral with a single size has been derived and
presented by an exponential curve that is used as basis for designing laterals
or submains of drip irrigation systems on level fields or on slopes. However,
under certain field conditions, the length of laterals and submains may be re-
latively long and have nonuniform slopes. The lateral and submain design may
use a series of different pipe sizes. A design technique is presented. The pur-
pose of this paper is to show that by designing laterals or submains with dif-
ferent pipe sizes (different diameters) the energy gradient line will be close
to the slope of the lateral or submain; therefore, the pressure variation will
be reduced.
77:08B-011
VISCOSITY AND SURFACE TENSION EFFECTS OF WEIR FLOW,
Ranga Raja, K.G., and Lai Asawa, G.
Roorkee University, Department of Civil Engineering, tlndia),
Journal of Civil Engineers, Vol. 103, No. HY10, p 1227-1231, October 1977. 2 fig,
1 tab, 9 ref, 1 append.
Descriptors: *Weirs, *Discharge measurement, *Discharge coefficient, *Flowmeters,
Hydraulics, Water properties, Overflow, Equations, Laboratory tests, Measurement,
Viscosity, Surface tension, Analysis, Discharge (water).
Weirs have been in use for a number of decades for the measurement of discharge
in channels. The existing discharge relations for weirs predict the discharge
reasonably well at high heads; however, the accuracy of these relations is ques-
tionable at low heads. This is mainly due to the fact that the effects of vis-
cosity and surface tension of the liquid are important at low heads. Proposed
discharge equations for predicting discharge at low heads introduced a correction
factor to account for the effects of viscosity and surface tension. The experi-
mentally determined correction factors were presented graphically. In general,
the data presented indicated an error of + or - 5% in the prediction of discharge.
77:O8B-012
AN INTRODUCTION TO EMISSION UNIFORMITY,
Solomon, K.
Rain Bird Company, 7045 North Grand Avenue, Glendora, California 91740.
Drip/Trickle Irrigation, Vol, 2, No. 1, p 6-10, January-February, 1977. 3 fig.
Descriptors: Irrigation systems, Irrigation engineering. Irrigation design,
Hydraulics, Hydraulic design, Irrigation efficiency, Flow rates, Uniform flow,
Uniformity coefficient.
There are good reasons to concern ourselves with emission uniformity. The more
nearly perfect a system is in terms of emission uniformity, the more it is likely
to cost. Various devices, material substitutions and design techniques are
available to minimize the problems leading to nonuniformity of emission, but they
all cost money and/or time. So the costs of approaching perfection must be
weighed carefully against the costs of not achieving it.
262
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77;OOB-013
PIPE SIZES PROM MODIFIED MOODY DIAGRAM,
Debler, W.
D6partment °f APPlied Mechanics and Engineering Science,
Descriptors: Hydraulics, Hydraulic design, Irrigation design, Irrigation engineer-
ing, Moody resistance diagram, Pipe flow. Pipes, Pipelines, Dimensional analysis.
In the course of developing some instructional material, a simple procedure evolved
to extend the useful information contained on the Moody Diagram. Concurrently
the_essence of that work's results was published by Lai and Lee 12) . Nevertheless,
a different point of view had been adopted in the development which makes the final
result useful, especially if one wishes to demonstrate the utility of dimensional
analysis .
77:08B-014
EMITTER SELECTION,
Gladigau, L.
Scientific Irrigation Systems, Department of Civil Engineering.
Drip/Trickle Irrigation, Vol. 2, No. 1, p 11-15, January-February, 1977. 2 fig,
1 tab.
Descriptors: Irrigation engineering, Irrigation systems, Irrigation design,
Hydraulics, Hydraulic design, Head loss. Friction, Flow rates.
Initially, emitter selection depends on the soil, plant requirement, emitter dis-
charge, water quality, and terrain of a particular location. Evaluation will
also include emitter cost and system risks. Generally, the emitters offering the
more desirable features and lower system risks have a higher unit cost. The ini-
tial emitter considered will have an influence oji the cost of the mainline and
filtration system and may need to be reevaluated before a final selection is made.
77:086-015
DRIP/TRICKLE PIPE NETWORK DESIGN,
Hamisch, F.
Ag Water, 22008 Riverside, Shafter, California 93263.
Drip/Trickle Irrigation, Vol. 2, No. 1, p 23-26, January-February, 1977. 1 fig,
1 tab.
Descriptors: Irrigation engineering, Irrigation systems, Irrigation design,
Hydraulics, Hydraulic design, Irrigation systems, Head loss, Friction, Flow rates.
The piping network is the means for taking water from its source and delivering it
to the emitter in adequate amounts and with the appropriate pressure. The design
of this system must be made from a sound engineering approach. The total system
must be the most cost effective for the particular application. The least initial
capital cost frequently is not the least expensive system for the user. The
addition of higher pressures and their related annual operating costs may exceed
the initial savings of the "least expensive" system in a short time. Power, water,
and other costs are rising rapidly, and it is the designer's responsibility to
consider the total costs.
77:08B-016
QUADRANT-PLATE WEIR,
Ramamurthy , A . S . , Subramanya , K . , and Pani , B . S ,
Concordia University, Department of Civil Engineering. Montreal r Canada .
Journal of the Hydraulics Division, American Society of Civil Engineers, Vol. 103,
No. HY12, Proceedings Paper 13395, p 143,1-1441, December 1977. 9 fig, 3 tab, 8
ref, 2 append.
Descriptors: *Weirs, 'Discharge (water) , *Flowmeters, *Ra ^"9 ^ves Theoretical
analysis, Measurement, Flow, Hydraulics,;, Laboratory tests, Equations, Data col
lections, Discharge coefficient,
263
-------
The sample weir flow equation was integrated numerically for a quadrant plate weir
to show that the head-discharge relationship for this weir is approximately linear.
Theoretically, deviations from linearity (H vs Q) can be limited to 0,5% by a judi-
cious choice of the parameters that determine the weir geometry. The results of
experiments on selected weirs were in agreement with the predicted relationships.
The coefficient of discharge for the quadrant-plate weir is a function of the ap-
proach channel Froude number. For very low Froude numbers (F less than 0.1), the
coefficient of discharge asymptotically approaches a value of 0.61.
264
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SECTION XXXIII
ENGINEERING WORKS
HYDRAULIC MACHINERY (GROUP O8C)
77:08C-001
PROCEEDINGS OF THE SOLAR IRRIGATION WORKSHOP,
The Energy and Development Administration, Sandia Laboratories, Albuquerque,
New Mexico.
Proceedings of the Solar Irrigation Workshop, Albuquerque, New Mexico, p 1-60,
July 7-8, 1977.
Descriptors: Energy, Pumps, Pumping plants. Irrigation wells, Irrigation ef-
ficiency. Economics, Irrigation systems, Wind velocity.
The Energy and Development Administration Solar Irrigation Workshop held in
Albuquerque, New Mexico, July 7, 1977, was structured to be a major vehicle
for information dissemination and technology transfer. It covered a wide range
of subject matter related to crop irrigation including current hardware, economics,
experiments, and international requirements. Speakers represented manufacturers,
ranchers, governmental entities, universities and research firms, ' An anticipated
heterogeneous attendee population dictated a format of many brief presentations
rather than fewer more detailed discussions, This was done to expose the parti-
pants to the various expert speakers and to give them a cursory introduction to
their particular expertise. These proceedings reflect the same intent. They
consist of one page abstracts for each presentation, a brief biographical sketch
of each speaker and sources for further information on each subject. The form
and format is somewhat loose, but hopefully justified by our goal to publish
prior to the conference. This goal was accomplished and served to provide the
workshop participants with valuable information enabling them to assess the
speakers' subject matter prior to the presentation.
265
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SECTION XXXIV
MANPOWER, GRANTS, AND FACILITIES
RESEARCH FACILITIES (GROUP 09C)
77:09C-001
RESEARCH AND DEMONSTRATION APPROACH TO DEVELOPMENT OF APPROPRIATE SALINITY
CONTROL TECHNOLOGIES FOR GRAND VALLEY,
Skogerboe, G.V., and Walker, W.R.
Colorado State University, Department of Agricultural and Chemical Engineering,
Fort Collins, Colorado 80523.
Proceedings of National Conference on Irrigation Return Flow Quality Management,
Colorado State University, Fort Collins, Colorado, p 353-359, May 16-19, 1977,
5 fig, 4 ref.
Descriptors: Irrigation, Irrigation practices, Salinity, Seepage, Colorado River,-
Irrigation systems.
Introduction of channel seepage and irrigation percolation losses into the underT
lying soils and marine aquifer, and the eventual return of these flows to the
Colorado River with their large salt loads, make the Grand Valley in western
Colorado one of the more significant salinity sources in the Upper Colorado River
Basin. The Grand Valley Salinity Control Demonstration Project was formulated to
delineate the magnitude of the water and salt flow components from the irrigation
systems to evaluate the effectiveness of various water management technologies in
reducing the salt load reaching the Colorado River, and to demonstrate appropriate
technologies on farmers' fields.
266
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SECTION XXXV
AUTHOR INDEX
Abernathy, G.H.
77:03F-106
Acharya, H.S.
77:02F-045
Affleck, S.B.
77:056-016
Aguade, E.
77:048-006
Aiken, J.D.
' 77:02F-035
Alberts, E.E.
77:07B-020
Alessi, J.
77:03F-058
Alexander, D.M.
77:04A-026
Alexander.- M.
77:026-159
Alfaro, J.F.
77:02G-058
Allen, J.F.
77:020-054
Allen, R.G.
77:03F-062
Allen, R.R.
77:03F-020
77:04A-040
Allmaras, R.R.
77:02G-082
Alvarez, E.I.
77:020-008
Amato, M.
77:02G-161
77:020-162
Amble, V.N.
77:03F-074
Amemiya, M.
77:03F-051
Amerman, C.R.
77:02G-128
Amoozegar-Fard, A.
77:02G-020
Anderson, J.L.
77:020-023
77:020-024
Anderson, K.
77:06E-003
Anderson, R.L.
77:06E-010
Appell, G.
77:07B-022
Ardakani, M.S.
77:020-068
77:04B-013
Arkin, G.F.
77:07B-033
Aron, G.
77:020-095
77:04A-022
Arvlanandan, K.
77:07B-012
Ashmead, R.M.
77:056-023
Asmussen, L.E.
77:050-002
Atkinson, T.C.
77:02F-030
Au, A.K.
77:020-067
Avnimelech, Y.
77:020-134
Axthelm, D.D.
77:02F-042
77:02F-044
Ayars, J.E
77:056-013
Ayers, R.S
77:050-001
Aylmore, L.A.G.
77:02G-004
Babcock, K.L.
77:020-084
Babu, D.K.
77:020-019
Baier, R.W.
77:05B-054
Baird, F.L.
77:02F-043
Baker, D.E.
77:020-133
77:05B-050
Baker ,- F. G .
77:02G-174
Baker, J.L.
77:05B-030
77:056-024
Balek, J.
77:02D-008
Ballaux, J.C.
77:020-150
77:058-032
Bar-Yosef, B.
77:03F-004
Barfield, B.J.
77:02D-010
77:02J-015
77:02J-019
77:02J-039
77:03F-096
77:04D-004
77:04D-007
Barker, J.
77:02G-091
Barlow, E.W.R.
77:03F-055
Barlow, T.
77:02J-022
Barnhisel, R.I.
77:020-121
Barr, D.E.
77:02F-016
Barrett, J.W.H
77:06A-001
267
-------
Bartlett, R.J.
77:03F-031
Basak, P.
77:02F-050
77:02F-052
Bathchelder, A.R.
77:058-010
Batu, V.
Bauer, A.
77:04A-032
77:03F-112
Bausch, W.
77-.02G-037
77:03F-023
77:04A-004
77:07B-019
Bean, E.L.
77:03F-081
Beasley, D.B.
77:02J-020
Beck, L.A.
77:Q6E-001
Bedient, P.B.
77:05B-027
Beese, F.
77:026-003
77:026-060
Bellis, W.H.
77:05B-021
Belt, G.H.
77-.03B-001
Benyamini, Y.
77:026-050
Benz, L.C.
77.-03F-019
Berk, W.J.
77:05B-019
Berndt, H.D.
77:040-006
Berthouex, P.M.
77:05A-009
Beth, F.
77:04A-028
Bevilacqua, D.P.
77:08B-006
Beyerlein, D.C.
77:02E-003
Bhattacharya, A.K.
77:04B-002
Bhattacharya, R.N.
77:02F-002
Bianchi, W.C.
77:05A-007
77:058-018
Biggar, J.W.
77:026-041
77:026-062
77:02K-005
77:05B-012
77:056-034
Bingham, F.T.
77 :02G-066
77:058-028
Bird, J.W.
77:06E-013
Birtles, A.B.
77:02F-025
Bishop, A.B.
77:050-003
77:06A-002
Black, J.H.
77 :02F-037
77:046-007
Blackard, J.
77:02J-023
Blackman, W.C., Jr.
77:05G-021
Blackmer, A.M.
77:02G-165
77:07B-008
Blancher, R.W.
77:026-069
Bliesner, R.D.
77:05B-003
Bloom, P.R.
77:026-130
77:02G-131
Bloomfield, R.A.
77:026-137
Bloomsburg, G.L.
77:02G-137
Boast, C.W.
77:02F-008
Boersmo, L.
77:03F-055
Bollen, W.B.
77:02G-158
Bondurant, J.A.
77:02J-006
77:02J-037
77:04A-042
Bos, M.G.
77:04A-011
Bostock, C.A.
77:04B-004
Boswell, F.C.
77:05B-036
Boulton, N.S.
77:02F-047
77:02F-048
Bouma, J.
77:026-023
77:026-024
Bourodlmos, E.L.
77:05B-025
Bowen, J. E.
77:03F-130
Bowie, A.J.
77:02J-029
Bowler, D.6.
77:026-071
Boyd, C.E.
77:078-004
Boyer, J.S.
77:03F-006
Bo.ysen, S.M.
77:02J-035
Bradford, J.M.
77:040-001
Brakensiek, D.L.
77:026-011
77:026-093
77:026-138
Brash, D.W.
77:03F-015
77:03F-016
Bravo, N.J.
77:08B-008
Bree, J.
77:026-087
Brehm, R.D.
77:040-005
Bremner, J.M.
77:026-119
77:026-165
77 :07B-008
Bresler, E.
77:026-056
77:02G-080
77:026-081
268
-------
Brewer, H.L.
77:07B-033
Bridges, T.C.
77:020-010
Broadbent, F.E.
77:026-040
77:02G-099
77:02G-103
77:02K-005
Brockway, C.E.
77:04A-006
Brosz, D.D.
77:021-016
Brosz, D.J.
77:03F-077
Broughton, R.S.
77:048-002
Brown, B.D.
77:07B-016
Brown, J.C.
77:03F-022
Brown, K.W.
77:020-102
77.-05B-006
77:05B-011
Brown, M.J.
77:03F-042
Brown, R.W.
77.-02G-091
Bruce, R.R.
77:020-007
77:03F-044
Brutsaert, W.
77:020-001
77:02F-013
77:02G-029
Bubenzer, G.D.
77:02G-140
Buchheim, J.F.
77:03F-050
Buchholz, J.R.
77:058-005
Bucks, D.A.
77:04A-035
77:056-035
Bulkley, J.W.
77:06A-003
Burau, R.G.
77:02G-106
77:076-012
Buresh, R.
77:076-032
Buresh, R.j.
77:05A-002
Surges, S.J.
77:02E-006
Burt, G.W.
77:058-015
Burwell, R.E.
77:02J-046
77:05B-004
77:078-020
Busch, C.D.
77:088-009
Busch, J.R.
77:03F-062
77:04A-006
Buzio, C.A.
77:056-015
Caldwell, A.C.
77:03F-109
Calvert, D.V.
77:058-041
Cameron, D.R.
77:02G-021
Campbell, M.D.
77:02G-055
Carlile, B.L.
77:05G-005
Carlton, A.B.
77-.02G-040
Carmack, W.J.
77:02J-033
Caro, J.H.
77:05G-040
77:05G-023
Carter, D.L.
77:02J-006
77:04A-042
Carter, J.N.
77:05B-035
Gary, J.W.
77:07B-014
Casey, M.R.
77:078-021
Castro, C.L.
77:02G-135
Celnicker, A.C.
77:05G-021
Cerda, A.
77:05B-028
Chadbourne, B.
77:02G-130
Chan, Y.K.
77:02F-001
77:02F-023
Chandrasekaran, D.
77:088-005
Chang, A.C.
77:02G-168
Channon, M.C.
77:03C-001
Chapin, R.
77:03F-029
Chaplin, C.
77:020-010
Chau, W.C.
77:02F-034
Chauhan, H.S.
77:02F-017
Chen, M.
77:050-004
Cheng, P.
77 :02F-034
Chesness, J.L.
77:03F-080
77:03F-086
Chichester, F.W.
77:056-004
Chidley, T.R.E.
77:02F-020
Chien, S.H.
77:02G-113
Chieng, S-T.
77:048-002
Childs, S.W.
77:020-011
Chin Choy, E.W.
77 :03F-039
Chopra, M.M.L.
77:03F-074
Chow, T.L.
77:02G-016
Christiansen, J.E.
77:05C-002
269
-------
Chu, S.T.
77:02F-032
77:02G-075
77:02G-125
Clapp, D.W.
77:02F-041
Clark, D.L.
77:03A-001
Clark, R.B.
77:03F-022
Clothier, B.E.
77:02G-065
Cochran, V.L.
77:03F-012
Coelen, S.P-
77:04A-022
Cole, D.W.
77:02G-101
Collis-George, N.
77:02G-028
Colorabera, P.M.
77:02G-002
Conklin, L.
77:02J-007
Cutler, J.M.
77 :02I-007
Daigger, G.T.
77:050-002
Daigger, L.A.
77:03F-127
Dalai, R.C.
77:02G-110
Dane, J.H.
77:02G-176
Daniel, W.H.
77:03F-100
Das, O.K.
77:03F-046
Davids, G.
77:03F-028
Davidson, J.M.
77:02G-022
77:021-003
77:05B-001
Davis, D.R.
77:02J-005
Davis, H.H.
77:02E-003
Delaney, R.H.
77:02G-100
Deluane, R.D.
77:02G-109
Delwiche, C.C.
77:058-014
77:07B-003
Dennis, C.W.
77:020-092
Derr, D.
77:03F-026
Deuel, I.E., Jr.
77:05B-006
Deuel, L.E.
77:05B-011
Dhillon, P.
77:03F-026
Dick, W.A.
77:02G-149
77:07B-018
Digiano, F.A.
77:05D-008
Dillow, D.W.
77:02G-104
Cooley, R.L.
77:02F-010
Cooper, J.D.
77:02G-047
Corapcioglu, M.Y.
77:02F-013
Couvillon, G.A.
77:03F-086
Cox, W.E.
Cox, W.J.
77:06E-007
77:03F-032
Crawford, N.H.
77:02E-003
77:056-026
Creel, B.J.
77:04A-009
Crow, F.R.
77:02E-005
Cruse, R.M.
77:02G-079
Davis, R.M.
77:03F-052
Davis, R.W.
77:07B-027
Davis, S.
77:03F-092
77:03F-114
77:04B-009
Dawes, W.H.
77:07B-021
Day, J.C.
77:03F-005
Day, P.R.
77:02G-111
De Datta, S.K.
77:02G-008
Debler, W.
77:088-013
DeBoer, D.W.
77:021-016
77:03F-079
77:04A-031
Dines, A.J.
77:06A-005
Dixon, R.M.
77:026-076
Dobrowolski, F.
77:06E-008
Doering, E.J.
77:03F-019
Donigian, A.S.
77:02E-003
Donigian, A.S., Jr.
77:058-026
Douglas, L.A.
77:05B-025
Dransfield, A.S.
77-.02G-055
Dreizin, Y.C.
77:048-003
77:048-012
Dronsfield, A.S.
77:03F-069
Cumberbatch, E.R.St.J.
77:03F-033
DeJong, J.F.
77:02J-044
Duble, R.L.
77:03F-076
270
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Duguid, J.O.
77:02F-012
Duke, H.R.
77:02G-141
77-.05B-010
Dumenil, L.C.
77:02G-119
Duncan, W.G.
77:03F-096
Earl, K.D.
77:03F-010
77:03F-011
Eavis, B.W.
77:03F-033
Eck, H.V-
77:02G-144
Edling, R.J.
77:03F-063
77:040-007
Edwards, K.W.
77:05A-006
Edwards, R.W.
77:026-073
Ehrler, W.L.
77:02L-001
Eivazi, F.
77:02G-164
Ekin, L.G.
77:02G-082
El-Ghamry, W.M.
77:02G-033
Elliott, H.A.
77:058-023
Elliott, L.F.
77:03F-012
Elliott, L.S.
77:02J-043
Elprince, A.M.
77:02G-111
77:05B-007
Enfield, C.G.
77:05E-002
England, C.B.
77:02G-014
Engleman, R.L.
77:02J-011
Erbach, D.C.
77:03F-041
Escarzaga, R,
77:02G-152
Estes, R.D.
77:02G-117
Evans, R.G.
77.-04A-038
77:05A-005
77:056-014
77:05G-013
Falco, J.W.
77 :02J-031
Fan, L.T.
77:05G-018
Fangmeier. D.D.
77:03F-090
Fenn, L.B.
77:02G-152
77:05B-043
Fenster, c.R.
77:02J-032
Fernando, M.J.
77:078-012
Fetter, C.W., Jr.
77:048-005
77:050-005
Fischbach, P.E.
77:02G-096
Fisher, P.O.
77:076-005
Fiskell, J.P.A.
77:058-001
Fitzsiminons, D.W.
77:03F-062
77:04A-006
Fluhler, H.
77:02G-010
77:048-013
Fogel, M.
77:02J-005
Follett, R.F.
77:03F-019
Folsom, B.L.
77:078-013
Ford, W.B.
77:078-009
Foroud, N.
77:04B-002
Foss, J.E.
77:058-015
Foster, G.R.
77:02J-025
77:02J-041
77:02J-042
Fox, R.L.
77:02G-155
Francis, L.
77:03F-102
Francois, L.E.
77:030-001
Frank, A.B.
77:03F-034
77:03F-035
Franklin, W.T,
77:030-002
Fraser, G.O., Jr.
77:03F-105
French, O.F.
77-.05G-035
Frenkel, H.
77:02G-064
Frere, M.H.
77:05G-023
Fried, M.
77:058-038
Frind, E.G.
77:05B-008
Fritton, D.D.
77:058-050
77:06D-002
Frown, G.A.
77:050-006
Fryberger, I.S.
77:058-021
Fryrear, D.W.
77:03F-020
Fuchs, M.
77:020-002
Fuerstenau, D.W.
77:02G-106
Fukuo, Y.
77:02F-028
Galindo, G.G.
77:02G-066
Gambolati, G.
77:02F-006
Garcia-Miragaya, J.
77:02G-088
271
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Gardner, W.R.
77:021-014
77:021-015
Garner, M.M.
77:03F-025
Gartner, A.
77:040-002
Carton, J.E.
77:03F-039
Garvey, P.M.
77:03F-080
Gascho, G.J.
77:03F-064
Cast, R.G.
77:02G-098
77:02G-121
Gauden, J.P.
77:02G-077
Gaudu, R.
77:02G-094
Gaum, C.H.
77:068-002
Gear, R.D.
77:02G-055
Gelhar, L.W.
77:04A-009
Geschwender, R.C.
77:07B-031
Ghaibeh, A. Sh.
77:02D-004
Ghildyal, B.P-
77:02F-017
77:021-002
Ghiorse, W.C.
77:026-159
Gibbs, M.M.
77:078-002
Gibson, J.A.
77:06E-014
Gilbert, R.G.
77:04A-035
Giles, J.F.
77:021-012
Gill, M.A.
77:04A-015
Gilley, J.R.
77:020-011
77:03F-136
77:04B-015
Gilliam, J.W.
77:03F-049
Gilmour, J.T.
77:05C-004
Gisser, M.
77:03F-018
Gitlin, H.M.
77:04A-014
77:08B-010
Gladigau, L.
77:088-014
Gleaton, J.
77:056-011
Godden, D.P.
77:03F-013
Goh, K.M.
77:03F-015
77:03F-016
Goldhamer, D.A.
77:026-039
Gole, C.V.
77:03F-074
Goswami, K.P-
77:05B-009
Grady, C.P.L., Jr.
77:050-002
Graham, W.G.
77:02F-041
Grant, D.M.
77:078-026
Green, F.H.W.
77:026-072
Green, R.E.
77:058-009
Gregg, P.E.H.
77 :03F-015
77:03F-016
Gregory, J.M.
77:026-139
77:02J-016
Grenney, W.J.
77:02J-038
77:050-003
Grier, H.E.
77:050-007
Griffin, R.A.
77:02G-067
Griffith, D.R.
77:03F-087
Grille, L.
77:06E-008
Grimes, D.W.
77:03F-099
Groenevelt, P.H.
77:020001
Groote, S.G.
77:026-092
Gross, T.A.
77:06A-003
Guitjens, J.C.
77:058-037
Gupta, G.C.
77:050-007
6upta, S.K.
6upta, V.
77:02G-041
77:026-009
Gupta, V.K.
77 :02F-002
.Gurovich, E.
77:02G-108
Guthrie, D.L.
77:078-024
Gutschick, V.P.
77 :03F-131
Haan, C.T.
77 :02D-009
77:02J-019
77:03F-096
77:040-004
77:040-007
Hachum, A.Y.
77:02G-058
Hadas, A.
77:026-006
Hagan, R.E.
77:03F-002
Hagan, R.M.
77:030-002
Hagan, W.R.
77:02J-034
Hahne, H.C.H.
77:026-147
77:026-171
Haimes, Y.Y.
77:048-003
77:04B-012
272
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Haith, D.A.
77:03F-066
77:o5B-029
Hakonson, T.E.
77:05B-005
Hallsworth, E.G.
77-.02G-110
Halvorson, A.D.
77:07B-006
Hamisch, F.
77:04A-024
77:086-015
Hamon, W.R.
77:026-138
Hanks, R.J.
77:02G-015
77:03C-002
77:03F-126
77:04A-002
77-.05B-003
77:05G-006
Hanson, C.L.
77:02E-002
77:02J-011
Hargrove, R.
77:03F-023
77:04A-004
Hargrove, R.S.
77-.02G-037
77:058-042
Hargrove, W.L.
77:02G-104
77:058-043
Harmon, W.C.
77:078-011
Harper, L.A.
77:02G-007
Harrington, R.A.
77:02E-001
Harris, D.G.
77:03F-034
77:03F-035
Harris, J.
77:078-009
Harris, W.
77:03F-014
Harris, W.S.
77:02G-117
Barter, R.D.
77:02G-133
Hassan, F.A.
77 :02D-004
Hassett, J.J.
77:021-013
Haug, R.M.
77 :02G-089
Haupt, H.F.
77:038-001
Hauser, E.W.
77 :05G-002
Hauser, V.L.
77:02E-004
77:03F-095
Haverkamp, R.
77:02G-027
Hayes, J.C.
77:02J-015
77:02J-039
Heady, E.G.
77:02J-014
77:02J-045
77:03F-053
Healy, M.L.
77:05B-054
Heaney, J.P.
77:058-027
Becker, G.E.
77:088-002
Hedstrom, W.E.
77:088-006
Heerman, D.F.
77:04A-020
Heermann, D.F.
77:03F-088
77:05B-010
Heft, F.E.
77:02J-027
Heinemann, H.G.
77:02J-046
Helweg, O.J.
77:04A-001
Helyar, K.R.
77:03F-013
Hendershott, C.H.
77:03F-086
Hendrick, J.G.
77:03F-110
Herkelrath, W.N.
77:021-014
77:021-015
Herrera, I
77:046-010
Hess, J.D.
77:08A-001
Hess, R.E.
77:02G-069
Hickey, J.J.
77:05E-001
Highfill, R.E.
77:02J-026
Hiler, E.A.
77:04A-039
Hira, G.S.
77:02G-151
Hoa, N.T.
77:02G-094
Hockenbury, M.R.
77:050-002
Hoffman, D.L.
77:026-039
Hoffman, G.J.
77:021-006
77:058-028
Hogg, B.C.
77:03F-001
Hohn, C.M.
77-.04A-008
Holburt, M.B.
77:06E-002
Holmgren, G.G.S.
77:078-031
Holt, R.F.
77:02J-008
Horner, G.L.
77:04A-005
77:05B-012
Hornsby, A.G.
77:03F-007
Horton, M.
77:05A-004
77:05G-012
77 :05G-011
Horton, M.L.
77:02I-010
77:021-011
273
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Hossmer, L.R.
77:07B-013
Howell, T.A.
77:04A-039
Hoyt, G.D.
77:02B-001
Huang, C.P.
77:05B-023
Huber, W.C.
77:058-027
Buck, M.G.
77:021-017
Huggins, L.E1.
77:02J-020
Hull, J.E.
77:05G-017
Humpherys, A.
77:03F-068
77:03F-116
Hunsaker, V.E.
77:03F-126
Huszar, P.
77:06A-001
Hutka, J.
77:02J-001
Hwang, C.L.
77:05G-018
Hynes, R.
77:02G-170
Idike, F.
77:070-002
Idso, S.B.
77:02L-001
77:03F-054
Irwin, R.W.
77:026-122
77:040-003
Jackson, D.R.
77:026-001
Jackson, G.D.
77:03F-043
Jackson, R.D.
77:02L-001
77:03F-054
Jackson, R.H.
77:04A-021
Jacob, C.M.
77:02F-011
Jacober, F.C.
77:03F-111
Jacoby, E.L., Jr.
77:020-003
Jain, J.K.
77:03F-135
Jaiswal, C.S.
77:02F-017
Jat, R.L.
77:03F-046
Jauregui, L.U.
77:03F-093
Jegat, H.
77:02G-077
Jensen, M.E.
77:03F-008
Jeschke, J.L.
77:02J-033
John, P.H.
77:07B-002
Johnson, C.W.
77:02J-011
Johnson, D.W.
77:02G-101
Johnson, H.P-
77:02G-139
77:02J-016
77:05B-030
77:05G-024
Johnson, R.L.
77:02F-018
Johnston, W.R.
77:02G-122
Johnston, W.R.
77:05G-020
Johnstons, W.R.
77:021-004
Jolley, V.D.
77:02G-053
77:02G-120
Jonch-Clausen, T.
77:026-002
Jones, L.A.
77:058-049
Jones, M.B.
77:05B-014
77:07B-003
Jones, O.R.
77-.05B-034
Jones, W.E.
77:03F-022
Judy, C.H.
77 :04D-002
Juo, A.S.R.
77:058-032
Jurinak, J.J.
77:02G-078
77:02J-038
Jury, W.A.
77 :02G-010
77:03F-010
77 :03F-011
Juve, R.L.
77:078-031
Kamburov, J.
77:021-008
Kanchanasut, P.
77:058-001
Kanemasu, E.T.
77:020-005
Karmeli, D.
77:03F-021
77:03F-060
77:03F-061
77:04A-007
Kassas, M.
77:060-001
Katopodes, N.D.
77:04A-018
77:04A-019
77:05B-047
Kaushik, N.K.
77:058-053
Kay, B.D.
77:020001
Keeney, D.R.
77:03F-045
77:03F-056
77:05B-002
77:05B-017
Kelly, W.E.
77:02F-036
Kempf, 0.
77:078-029
Kennedy, S.
77:03F-104
Keren, R.
77:020-121
Kerr, J.P.
77:02G-065
274
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Khalid, R.A.
77:02G-109
Khengre, S.T.
77:02G-146
Kholdebarin, B.
77:058-051
Kibler, D.F.
77:060-002
Kiker, C.P.E.
77:06E-006
Kimball, B.A.
77:020-082
Kimberlin, L.W.
77:02J-026
77:02J-028
King, J.G.
77:038-001
King, L.G.
77:056-003
Kinnell, P.I.A.
77:02J-001
Kinney, W.
77:04A-005
Kipp, K.L., Jr.
77:02F-037
77:048-007
Kirkham, D.
77:02G-139
77:02J-016
77:058-016
Kirkham, M.B.
77:056-056
Kishi, Y.
77:02F-028
Kissel, D.E.
77:02G-104
77:05B-043
77:078-033
Klepper, B.
77:021-017
Klepper, R.
77:02F-027
Kley, W.
77:056-022
Klusman, R.W.
77:05A-006
Klute, A.
Knowles, R.
77:02G-170
Kodama, M.
77:04A-032
Koelliker, J.K.
77:02G-129
Koeppe, D.E.
77:021-013
Kohl, D.H.
77:03F-042
Kormilo, S.R.
77:078-030
Kouwen, N.
77:02E-001
Kovda, V.A.
77:02J-009
Kramer, P.J.
77:021-001
Krishnamurthi, N.
77:02F-031
Kroontje, W.
77:02G-147
77:02G-171
Krull, D.L.
77:03A-001
Kruse, E.G.
77:02G-141
77:04A-020
Kunkel, R.
77:056-005
Kuraz, E.V.
77:076-023
Kurihara, K.
77:02G-148
Laag, A.E.
77:026-145
77:048-009
Labadie, J.W.
77:03F-088
77:04A-001
Lacewell, R.D.
77:05C-005
Ladd, J.N.
77:026-161
77:02G-162
Laflen, J.M.
77:058-030
Laher, M.
77:02G-134
Laidlaw, I.M.S.
77:078-001
Lakatos, D.F.
77:026-095
Lakshminarayana, V.
77:02F-019
Lai Asawa, G.
77:08B-011
Land, L.F.
77:02F-022
Landa, E.R.
77:026-098
Lansford, R.R.
77:04A-009
Lapping, M.B.
77:03F-017
Larsen, R.
77:03F-118
Larson, C.L.
77:070-002
Larson, S.P.
77:02F-003
77:02F-029
Larson, W.E.
77:026-079
Lashkari, R.S.
77:056-018
Laura, R.D.
77:026-160
Laverdiere, M.R.
77:026-172
Law, J.P.
77:056-172
Law, J.P-, Jr.
77:03F-007
Layton, J.J.
77:06A-001
Lazenby, A.
77:03F-014
Lee, P.C.Y.
77:02F-012
Lee, Y.S.
77:03F-031
77:026-021
77:026-176
275
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Lefebre, V-
77:02F-040
Lehmann, E.I.
77:050-009
Leistra, M.
77:058-052
Lembke, W.D.
77:05D-001
Lenau, C.W.
77:02F-015
Leonard, R.A.
77:02G-007
Lettenmaier, D.P.
77:02E-006
Levin, M.J.
77:02G-001
Lewis, G.C.
77:03F-062
77:04A-006
Lewis, R.B.
77:02E-004
Liggett, J.A.
77:02F-009
Ligon, J.T.
77:02G-054
Lin, S.H.
77:02F-024
77:02G-124
77:02G-143
Lindeborg, K.H.
77:02J-007
Lindsay, W.L.
77:02G-112
Lloyd, J.W.
77:02F-020
Lobello, A.J.
77:06C-001
Lock, M.A.
77:07B-002
Long, R.B.
77:02J-007
Longenbaugh, R.A.
77:02F-031
Loomis, R.S.
77:021-007
Lowell, F.C., Jr.
77:078-028
Ludwiok, A.E.
77:021-012
77:05B-055
77:07B-035
Lund, L.J.
77:02G-038
77:02G-168
Lutz, J.A., Jr.
77:026-147
77:02G-171
Luxmoore, R.J.
77:02G-032
Lynne, G.D.
77:06E-006
Maas, E.V.
77:021-006
Maclntyre, J.L.
77-.02G-041
MacKenzie, A.F.
77:05B-048
Mahannah, C.N.
77:05B-037
Malcolm, H.R., Jr.
77:02J-013
Mallory, R.
77:03F-120
77:03F-122
Mancini, T.R.
77:03F-106
Manges, H.L.
77:04A-037
77:078-021
Mantz, P.A.
77:02J-003
Marelli, H.J.
77:02J-044
Marion, G.M.
77 :02G-084
Marshall, E.J.P.
77:02G-073
Martens, D.C.
77:05B-007
Martin, J.K.
77:02G-156
77 :02G-166
Martin, W.W.
77:03F-078
Martinez, T.
77:02G-144
Matousek, J.
77:078-023
Mattigod, S.V.
77:026-107
77:02K-003
Mawdsley, J.A.
77:020-001
McBride, M.B.
77:026-130
77:026-131
McCarthy, R.E.
77:02J-036
McClymont, G.L.
77 :02F-021
McDowell, LL.
77:056-032
McFarlane, J.C.
77:026-102
McHeniy, J.R.
77:05B-033
McLaren, A.D.
77:026-068
Logan, 0.
77:06E-012
Manley, D.W.
77:026-118
McLean, E.O.
77:02B-001
Logan, T.J.
77:028-001
77:02J-030
Loganathan, P.
77:026-106
Lomen, D.0.
77:026-049
77:026-061
Manley, R.E.
77:026-142
Mannering, J.V.
77:02J-032
Mansell, R.S.
77:058-001
77:05B-041
McMaster, 6.M.
77:03F-059
77:04A-006
McNeal, B.L.
77:056-005
McNeill, E.
77:05A-008
27b
-------
McPherson, H.G.
77-.03F-006
McRae, S.G.
77:076-017
McWhorter, D.B.
77:02F-004
77:058-013
77:05B-045
Meiri, A.
77:021-008
Meisinger, J.J.
77:058-035
Meister, A.D.
77:02J-014
Melamed, D,
77:020-015
77:05G-006
Melstad, J.D.
77:03F-079
Meneely, J.M.
77:02G-034
Miller, J.E.
77:021-013
Miller, R.D.
77:026-056
Miller, R.H.
77:02G-167
Miller, R.J.
77:056-012
Miller, W.W.
77:058-037
Mills, P.F.
77:03F-038
Mishoe, J.W.
77:03F-064
Mishra, B.K.
77:078-015
Misra, C.
Miwa, E.
77:078-015
77:02G-148
Morgan, W.H.
77:078-029
Morin, J.
77:02G-050
Morrison, J.
77:03F-024
Mortvedt, J.J.
77:02G-059
Moss, A.J.
77:02J-001
Mostertman, L.J.
77:05G-015
Mualem, Y.
77:02G-074
Mubarak, A.
77:02G-083
Mukhtar, M.
77 :05B-009
Mulkey, L.A.
77:02J-031
Menzel, R.G.
77-.02E-004
Mercado, A.
77:02F-049
Miyamoto, S.
77:058-040
Mero, T.
77:078-022
Merrill, G.
77:05G-010
Meyer, F.W.
77:05G-017
Meyer,- L. D.
77:02J-025
77:02J-041
77:02J-042
77:02J-044
77:078-011
Michalson, E.L.
77:02J-007
Miller, A.C., Jr.
77.-02G-095
Miller, D.E.
77:03F-048
Miller, E.E.
77:021-014
77:021-015
Miller, G.E.
77:02G-114
Mock, J.J.
Moe, R. C.
77:03F-041
77:02J-033
Mohammed, R.A.
77 :03F-090
Moldenhauer, W.C.
77:02J-028
77:03F-128
Moline, W.J.
77:03F-127
Monke, E. J.
77:02G-128
77:02J-020
77:02J-044
Moraghan, J.T.
77:05A-002
77:078-032
Morel-Seytoux, H.J.
77:028-002
Moreshet, S.
77:02D-002
Morgan, W.D.
77:06E-009
Mullen, G.J.
77:026-017
77:02G-031
Mullineux, N.
77:02F-023
Munns, D.N.
77:026-155
Murphy, L. S .
77:03F-109
Murray, W.A.
77:02F-018
Murty, V.V.N.
77:02F-038
77:02F-050
Musick, J.T.
77:04A-040
Mutchler, C.K.
77:02J-010
77:02J-029
Nakayama, F.S.
77:04A-035
77:05G-035
Narasimhan, T.N.
77:02F-014
Narayanan, R.
77:050-003
77:06A-002
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Navarro, A.
77:02F-039
Neff, R.
77:02G-034
Neibling, W.H.
77:02G-129
Neilsen, G.H.
77:05B-048
Nelson, D.W.
77:02G-173
77:02J-021
Nelson, M.J.
77:03P-119
New, L.
77:03F-113
77:03F-115
Newkirk, H.W.
77:04A-041
Newland, L.W.
77:02F-016
Newman, B.A.
77:048-001
Nielsen, D.R.
77:02G-017
77:02G-018
77:026-031
77-.02G-062
Nightingale, H.I.
77:05A-007
77:05B-018
Nikolski, Y.N.
77:03F-037
Nishita, H.
77:026-089
Nix, J.P.
77:02J-018
Nolte, B.H.
77:04D-005
Nor, Y.M.
77:02G-085
Nulsen, R.A.
77:021-005
Nye, J.R.
77:03F-101
Nyquist, W.E.
77:02G-046
Nystrom, J.B.
77:08B-002
Obbink, J.G.
77:04A-026
O'Connor, G.A.
77:02G-013
Oertli, J.J.
77:05B-051
Ohmes, F.E.
77:026-129
77:04A-037
Olness, A.
77:05G-033
Olsen, E.G.
77:05C-002
Olsen, R.A.
77:02G-083
Olsen, B.R., Jr.
77:03F-103
Onken, A.B.
77:026-037
77 :02G-097
77:03F-023
77:04A-004
77:058-042
77:05C-005
77:078-019
Onstad, C.A.
77:02G-093
77:02J-029
77:02J-041
77:02J-042
Ortiz, N.V.
77:088-001
Ortolano, L.
77:06A-004
Osborn, G.
77:026-059
Oster, J.D.
77:026-044
Otterby, M.A.
77:04A-031
Page, A.L.
77:026-088
77:02G-168
Palacios, E.V.
77:03F-005
Palkovics, W.E.
77:026-025
Pallas, J.E., Jr.
77:03F-044
Palmer-Jones, R.W.
77:03F-003
Pani, B.S.
77:08B-016
Papendick, R.I.
77:03F-012
77 :03F-048
Parfitt, R.L.
77:026-132
Parlange, J.Y.
77:026-019
77:026-127
Parsons, J.W.
77:026-161
77:026-162
Patrick, W.H., Jr.
77:026-109
77:021-019
Pavlik, 0.
77:02D-008
Peaslee, D.E.
77:026-150
Peck, A.J.
Peri, 6.
77:026-032
77:03F-021
77:03F-060
Perold, R.P.
77:04A-013
Perrens, S.J.
77:02G-035
Perrier, E.R.
77:02J-018
77:078-009
Peters, D.B.
77:07B-036
Petersen, G.W.
77:026-025
Philip, J.R.
77:026-002
Phillips, R.E.
77:07B-029
Pick, T.A.
77:02B-002
Pierre, W.H.
77:026-053
77:026-120
278
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Piest, R.F.
77:02J-040
77:02J-043
77:040-001
Finder, G.F.
77:056-008
Pitney, M.
77:03F-082
Pitt, W.A.J., Jr.
77:05G-017
Ploss, L.F.
77:03F-050
Pohoryles, S.
77:03F-018
Polemio, M.
77:078-037
Poulovassilis, A.
77:026-030
77:02G-033
Power, J.F.
77:03F-058
Prather, R.J.
77:02G-154
Pratt, P.F.
77:02G-038
77:026-145
77:02K-005
77:048-009
Price, E.P-
77:02G-045
Price, J.D.
77:05B-006
77:058-011
Pruitt, W.O.
77:03C-002
77:058-012
Pugner, P.E.
77:05D-003
Purtymun, W.D.
77:058-005
Putkey, T.A.
77:02F-041
Qureshi, N.A.
77:08B-002
Raats, P.A.C
77:02G-026
Racotch, A.
77:02J-002
Radosevich, G.E.
77:06E-011
77:06E-005
77:06E-004
77.-06A-004
Rains, D.W.
77:021-007
Rajapopalan, S.P.
77:02F-019
Rajaratnam, N.
77:08B-001
77:086-003
Ramamurthy, A.S.
77:088-016
Raney, R.J.
77:020-005
Ranga Raja, K.G.
77.-08B-011
Rango, A.
Rao, L.
Rao, N.S.
77:026-034
77:088-005
77:08B-005
Rao, P.S.C.
77:026-022
77:021-003
Rauch, H.W.
77:02K-002
Rausch, D.L.
77:056-031
77:05G-032
77:05G-033
Ravelo, C.J.
77:04A-039
Ravina, I.
77:026-108
Rawlins, S.L.
77:04A-027
Rawls, w.J.
77:02G-138
Reddy, C.N.
77:021-019
Reddy, G.Y.
Ree, W.O.
77:028-001
77:02E-005
77:03F-089
Reed, J.R.
77:02F-023
Reeves, M.J.
77:02F-025
Reginato, R.J.
77:02L-001
77:03F-054
Reichman, G.A.
77:03F-019
Reicosky, D.C.
77.-07B-036
Reisenauer, H.M.
77:03F-032
Reins on, I.
77:04B-006
Rennes, A.
77:026-071
Replogle, J.A.
77:088-007
77:078-025
Reule, C.A.
77:078-006
Reuss, J.O.
77:021-012
77:05B-055
77:078-035
Rhoades, D.L.
77:05G-016
Rhoades, J.D.
77:056-001
77:07B-037
77.-07B-006
Ribbens, R.W.
77:056-008
Rich, C.I.
77:058-007
Richey, C.B.
77:03F-087
Richter, W.
77:026-060
Rickman, R.W.
77:026-082
Ritchie, J.C.
77:058-033
Robinson, W.H., Jr.
77:05A-001
Robinson, J,B.
77:058-053
279
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Rochester, E.W.
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Rodgers, N.
77:03P-097
Rodriguez, R.
77:03F-094
Roefs, T.G.
77:04B-004
Rogers, J.S.
77:05B-041
Rogers, R.D.
77:02G-090
Rogowski, A.S.
77:020-003
Rolfe, P.F.
77:02G-004
Rolston, D.E.
77:02G-039
77:02G-103
77:02G-135
77:07B-016
Romkens, M.J.M.
77:02G-173
77:02G-021
Rosenburg, N.J.
77:03F-040
Rosensheim, J.S.
77:05E-001
Rosenthal, W.D.
77:020-005
Ross, J.D.
Ross, R.
77:02E-004
77:03F-009
77:058-044
77:05G-037'
Ross, W.D.
77:02G-100
Roth, C.B.
77:020-173
77:02J-021
Rouse, W.R.
77:03F-038
Routson, R.C.
77:050-003
Roye r, J. M.
77:02G-047
Rubin, H.
Ruen, J.
77:02F-007
77:03F-117
Rushton, K.R.
77:02F-001
77:02F-026
Russo, D.
77:02G-080
77:02G-081
Rutherford, T.
77:02G-089
Sabey, M.B.
77:06E-011
Saffigna, P.G.
77:03F-045
77:03F-056
77:058-002
77:05B-017
Sagar, B.
Sagi, R.
77:02F-046
77:02J-002
Sahrawat, K.L.
77:026-163
Sain, P.
77:02G-099
77:05B-053
Sammis, T.W.
77:04A-008
Sandhu, B.S.
77:021-010
77:021-011
Sandia Laboratories
77:080001
Sandoval, F.M.
77:03F-111
Sangi, A.K.
77:02F-027
Savant, N.K.
77:02G-146
Sawhney, B.L.
77:046-014
Saxton, K.E.
77:03F-027
77:05B-004
Say, E.W.
77:06A-005
Scharplax, J.D.
77:07B-021
Scherer, C.R.
77:050-003
Schleicher, J.
77:03F-071
77:03F-121
Schmidt, K.D.
77:05B-020
Schmugge, T.J.
77:02G-034
Schneider, A.D.
77:05B-034
Schreiber, J.D.
77:05G-031
77:05G-032
Schuman, G.E.
77:02J-046
77:05B-004
77:078-020
1 Schwab, G.O.
77:040-005
77:08B-008
Schwartz, F.W.
77:02F-021
77:02F-033
Scott, V.H.
77:02F-038
Scotter, C.N.G.
77:02G-073
Scotter, D.R.
77:02G-065
Selim, H.M.
77:02G-022
77:021-003
77:058-001
Sepaskhah, A.R.
77:021-009
Shaffer, M.J.
77:05G-008
77:056-019
Shahane, A.N.
77:03F-072
Shalhevet, J.
77:021-008
Sharma, R.B.
77:021-002
Sharma, T.C.
77:040-003
280
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Sharpley, A.M.
77.-05A-003
Sheahan, N.T.
77:048-011
Shearer, G.
77:020-113
Shearer, M.N.
77:03F-030
77:04A-036
Shelton, C.H.
77:02J-017
Sheridan, J.M.
77:050-002
Shih, S.F.
Shoji, K.
77:03F-064
77:03F-067
Shrader, W.D.
77:05B-030
Shuford, J.W.
77:05B-050
Shuman, L.M.
77:020-086
Siebert, J.E.
77:07B-005
Silberman, E.
77:06B-001
Simmons, C.S.
77:020-041
Simpson, E.S.
77:048-004
Sinha, B.K.
77:020-051
Sionit, N.
77:021-001
Sisson, J.B.
77:04A-003
Sitar, N.
77:04B-006
Skaggs, R.w.
77:020-116
77:020-126
77:03F-049
77:04A-025
Skogerboe, G.V.
77:03F-057
77:05A-005
77:058-013
77:050-013
77:050-014
77:05G-022
77:06E-005
77:07C-001
Slabbers, P.J.
77:02D-006
Slack, D.C.
77:02D-009
77:020-123
77:07C-002
Sloneker, L.L.
77:03F-128
Small, L.
77:03F-026
Sims, J.R.
77:03F-043
Smallwood, C., Jr.
77:02J-013
Smart, P.L.
77:07B-001
Smith, S.J.
77:02G-104
77:026-114
Smith, S.W.
77:03F-057
77:05A-005
77:050-013
Solomon, K.
77:04A-032
77:04A-034
77:08B-012
Solomon, S.I,
77:02E-001
Soltanpour, P.N.
77.-05B-055
77:07B-035
Sommerfeldt, T.G.
77:050-036
Sorenson, R.E.
77:03F-129
Spaulding, B.W.
77:03F-053
Spencer, J.
77:05A-004
77:050-011
77:050-012
Splinter, W.E.
77:02D-011
Spomer, R.G.
77:02J-043
77:02J-046
Sposito, G.
77:02F-002
77:02G-009
77:02G-052
77:020-107
77:02K-003
Sinai, G.
77:02G-115
Smeck, N.E.
77:05B-049
Stammers, W.N.
77:058-053
Singer, M.J.
77:02J-023
Singh, N.T.
77:02G-151
Singh, S.R.
77:02F-011
77:02F-046
77:02G-051
Singh, U.P.
77:02G-054
Smika, D.E.
77:056-010
Smith, J.H.
77:02J-005
Smith, J.L.
77:05B-045
SmithV.J-P-
77:02J-011
Smith, R.E.
77:020-127
Stanford, G.
77:058-035
Stanhill, G.
77:020-002
Stansell, J.R.
77:03F-044
Starr, J.L.
77:02G-063
Steenhuis, T.S.
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Stegman, E.G.
77:03F-112
Stephenson, R.L.
77:05A-010
Stevenson, K.R.
77:021-005
Steward, R.B.
77:03F-038
Stewart, B.A.
77:05G-023
77:05G-040
Stewart, E.H.
77:05B-041
Stewart, J.I.
77:030002
Stivers, R.K.
77:020-046
Stolzy, J.L.
77:02G-032
Stolzy, L.H.
77:02G-010
77:04B-013
Stone, J.F.
77:03F-039
Stone, L.R.
77:020-005
77:05G-039
Strelkoff, T.
77:04A-017
77:04A-018
77:04A-019
77:05B-047
Streltsova, T.D.
77:02F-047
77:02F-048
Su, Y.S.
77.-05D-008
Suarez, D.L.
77:02G-064
77:02K-001
77:05G-016
77:05G-001
Subr amanya, K.
77:08B-016
Sullivan, P.
77:02G-009
Sullivan, T.E.
77:03F-126
Sunada, O.K.
77:02F-031
Sunderman, H.D.
77:02G-097
77:076-013
Swartzendruber, D.
77:026-046
Swenson, R.S.
77:04A-010
Swoboda, A. R.
77:02G-036
77:05G-026
Syers, J.K.
77:02G-071
77:05A-003
Symeonides, C.
77:078-017
Szuszkiewicz, T.E.
77:048-013
Tabatabai, M.A.
77:02G-085
77:02G-149
77:02G-164
77:076-018
Tandy, D.F.
77:060-002
Tang, Y.K.
77:02G-116
77:04A-025
Tanji, K.K.
77:02G-041
77:04A-005
77:058-012
77:05B-038
77:05G-034
Tanner, C.B.
77-.03F-056
77:058-002
77:058-024
Terman, G.L.
77:026-057
77:03F-047
The Task Committee
77:04A-012
77:05B-046
Theis, T.L.
77 :05D-006
Thirriot, C.
77:02G-094
Thomas, A.W.
77:026-007
77:026-141
Thomas, G.W.
77:058-039
Thorvig, L.
77:026-098
Thurtell, G.W.
77:021-005
Tiedje, J.M.
77:02J-024
Tillman, R.W.
77:02G-071
77:05A-003
Timmons, D.R.
77:02J-008
Tiwari, S.C.
77:050-007
Tofflemire, T.J.
77:050-004
Tolba, M.K.
77:05G-025
Tollner, E.W.
77:02J-039
77-.04D-004
Tomlinson, L.M.
77:02F-026
Touma, J.
77:026-027
Towle, C.L., Jr.
77:048-008
Toy, D.W.
Trava, J.
77:026-039
77:03F-088
Trescott, P.C.
77:02F-003
77:02F-029
Tromble, J.M.
77:02D-007
Trotter, R.J.
77:060-002
Trouse, A.C., Jr.
77:026-136
Trout, T.J.
77:058-045
282
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Tubbs, L.J.
77:05B-029
Tucker, B.B.
77:03F-109
Turk, G.
77-.08B-004
Turner, F.C.
77:056-006
77:053-011
Tyler, D.D.
77:05B-039
Unger, P.W.
77:03F-036
Unger, S.G.
77:02G-153
Vachaud, G.
77:026-027
77:02G-047
77:026-077
Vachirakornwatana, C.
77:040-004
Van De Pol, R.M.
77:026-018
77:05B-038
Van Der Ploeg, R.R.
77:02G-003
77:026-060
Van Genuchten, M.T.
77:026-012
77:026-013
77:05B-008
Van Schilfgaarde, J.
77:026-042
Vanderberg, A.
77:02F-051
Vauclin, M.
77.-02G-027
Veith, J.A.
77:026-052
Verma, S.B.
77:03F-040
Verstraete, W.
77:026-157
Vieth, G.R.
77:03F-001
Vincenty, C.
77:078-024
Vlachos, E.
77:06A-001
Vlek, P.L.G.
77:02G-112
Voets, J.P.
77:02G-157
Volz, M.G,
77:02G-063
77:02G-105
77:078-034
Von Bernuth, R.D.
77:04A-033
Voorhees, W.B.
77:03F-110
Vredenburg, R.T.
77:026-005
Wade, P.M.
77:026-073
Wade, J.C.
77:02J--045
Wagenet, R.J.
77:026-062
77:026-078
77:02J-038
Wagner, T.P.
77:06A-004
Waldron, L.6.
77:026-070
Wall, M.K.
77:021-018
Walker, P.H.
77:02J-001
Walker, P.N.
77:03F-065
77:050-001
Walker, T.W.
77:03F-015
Walker, W.R.
77:03F-057
77:05A-005
77:05G-007
77:056-009
77:05G-013
77:056-014
77:06A-006
77:06E-007
77:078-010
77:09C-001
Walsh, L.M.
77:03F-108
Walter, M.F.
77:026-140
77:03F-066
Wang, J.-K.
77:03F-002
Ward, A.D.
77:02J-019
Warneke, J.E.
77:026-168
Warrick, A.W.
77:026-017
77:026-020
77:026-031
77:026-043
77:026-049
77:026-061
Washington, D.R.
77:078-024
Watson, K.K.
77:026-035
Watts, D.6.
77:048-015
Weaver, R.M.
77:026-172
Weed, S.B.
77:03F-049
Weisz, R.N.
77:048-008
Wells, B.R.
77:050004
Wells, L.6.
77:020-009
77:026-126
Welsh, G.
77:03F-098
Wendt, C.W.
77:026-037
77:03F-023
77:04A-004
77:058-042
77:050-005
77:078-019
Wengert, N.I.
77:06E-010
Werner, D.
77:058-022
Westerdahl, L.E.
77:02J-018
Westerjnann, D.T.
77:058-035
Westfall, D.6.
77:058-006
283
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Wheeler, W.B.
77:058-041
White, A.W., Jr.
77:05G-002
White, E.L.
77:04A-022
77:060-002
White, G.M.
77:020-010
White, I.
77:02G-002
White, J.
77:03F-124
White, W.B.
77:02K-002
Whiteley, H.R.
77:05B-053
Whitlock, W.W.,
77:05B-
Jr.
031
Whitmore, J.C.
77:020-078
Wiebe, H.H.
77:02G-091
Wierenga, P.J.
77.-02G-005
77-.02G-012
77:02G-013
77:02G-018
77:02G-027
77:02G-077
77:026-175
77:04A-003
77:04A-029
Wiersma, J.L.
77:021-016
Wiese, A.F.
77:04A-040
77:05B-034
Wilkinson, J.F.
77:02G-167
Willardson, L.S.
77:02G-015
77:04A-002
77:056-003
77:05C-002
77:05G-006
Williams, J.R.
77:040-006
Williams, W.A.
77:058-014
77:07B-003
Willis, R.
77:046-001
Willis, W.O.
.77:026-005
77:03F-034
77:03F-035
Willis, C.G.
77:056-021
Wilson, D.O.
77:02G-169
Wilson, G.C.
77:02G-144
Wilson, T.V.
77-.02G-054
Wimberly, F.L.
77:02E-005
Wischmeier, W.H.
77:05G-023
Wischmeir, W.H.
77:05G-040
Witherspoon, P.A.
77:02F-014
Wolman, M.G.
77:02J-004
Wu, I.
Wu, I.-P.
77:04A-014
77:088-010
Yare, B.S.
77:056-019
Yates, R.
77:046-010
Yoshinari, T.
77:02G-170
Young, E.G.
77:02G-048
Young, H.Y.
77:056-009
Young, J.L.
77:03F-055
Young, L.B.
77:026-114
Young, R.A.
77:02J-010
77:070-002
Yu, K.Y.
77:05A-009
Zantua, M.I.
77:02G-119
Zaslavsky, D.
77:026-115
Ziemnicki, S.
77:02J-040
Zimmerman, D.C.
77:03F-058
Zubriski, J.C.
77:03F-109
Wiese, R.A.
77:03F-109
77:03F-129
Wilding, L.P.
77:056-049
Wood, J.D.
77:026-044
Woolhiser, D.A.
77:05G-023
77:056-040
Wildung,- R.E.
77:05C-003
Worthington, P.F.
77:02F-005
Wilke, O.C.
77:02G-037
77:03F-023
77:04A-004
77:056-042
77:050-005
77:078-019
Wright, J.L.
77:03F-042
Wright, M.E.
77:05A-001
-------
SECTION XXXVI
SUBJECT INDEX
Abatement
77:05D-009
Absorption
Acids
77:021-002
77:03F-032
77:053-054
77:05B-056
77:05A-010
Activated Sludge
77:050-002
Administrative Agencies
77:05G-021
Adsorption
77;
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77 :
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
02G-012
02G-013
02G-018
02G-021
02G-022
02G-052
02G-066
02G-067
02G-068
02G-086
02G-101
02G-106
02G-111
02G-121
02G-124
02G-130
02G-132
02G-133
02G-143
02G-147
02G-151
02G-154
02G-172
05B-001
05B-007
05B-023
05B-052
05B-054
05D-004
05D-005
Aeration
77:050-002
.s,zlcultur.il Activities
77:03F-007
Agricultural Chemicals
77:02E-004
77:058-006
77:05B-009
77:05G-OU
-------
Algorithms
77:04A-001
77:04B-001
Alkaline Soils
77:02G-164
Alkalinity
77:02F-030
Alluvial Aquifers
77:05B-005
77:058-020
77:05B-021
Alluvial Fans
77:02F-028
Alluvium
77:05B-021
Alternative Planning
77:04A-022
Alternative Practices
77:05G-024
Aluminum
77:02G-130
77:02G-131
Amino Acids
77:05A-010
77:078-001
Ammonia
77:02G-146
77:02G-152
77:05A-010
77:05B-025
77:05B-036
77:050-005
77:050-007
77:07B-033
Ammonification
77:02G-160
Ammonium Compounds
77:02G-068
77:05A-010
77:05B-051
Ammonium Salts
77:058-043
Analog Models
77:086-008
Analysis
77 :02D-001
77:02F-002
77:02F-017
77:02G-033
77:02J-041
77:058-050
77:08B-011
Analytical Techniques
77:020-001
77:02F-002
77:02F-012
77:02F-016
77:02F-026
77:02F-052
77:026-001
77:02G-005
77:02G-008
77:026-021
77:026-047
77:026-056
77:026-078
77:026-083
77:026-125
77:026-128
77:026-175
77:05A-003
77:05A-009
77:05A-010
77:05B-006
77:058-008
77:058-009
77:058-048
77:058-049
77:058-050
77:050-004
77:088-004
Animal Wastes
77:026-145
Anion Exchange
77:026-098
Aquicludes
Anions
77:02G-052
77:026-057
77:026-101
77:026-111
77:05B-042
Anisotropy
Annual
77:02F-019
77-.04B-004
Antecedent Precipitation
77:026-034
Apples
77:04A-026
Application Methods
77:021-016
77-.05A-010
77:06A-006
77:060-002
Appropriation
77:06E-013
Aqueous Solutions
77:026-001
77:03B-001
77:05A-009
77:05B-016
77:02F-0:
Aquifer Characteristics
77:02F-003
77:02F-010
77:02F-023
77:02F-029
77:02F-039
77:02F-040
77:02F-046
77:02F-047
77:02F-048
77:04B-007
77:05E-001
77:08B-004
Aquifer Management
77:048-010
Aquifer Systems
77:02F-022
77:048-010
77:06A-006
Aquifer Testing
77:02F-001
77:02F-006
77:02F-037
77:046-007
77 :04B-010
77:058-018
Aquifers
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77:
77 :
77:
77:
77:
77:
77:
77:
77:
~>~1 :
77:
77;
77;
77:
77:
77:
77:
02F-001
02F-004
02F-005
02F-006
.02F-007
02F-011
;02F-013
;02F-015
;02F-017
:02F-019
:02F-020
:02F-021
:02F-023
:02F-025
:02F-026
:02F-027
:02F-036
:02F-037
:02F-038
:02F-039
:02F-041
:02F-046
:02F-049
:02F-050
:02F- >5'
04A-001
04B-001
04B-004
048-006
048-008
04B-010
04B-011
286
-------
77:04B-012
77:05B-005
77:058-018
77:058-019
77:058-022
77:058-034
77:05E-001
77:05G-017
77:078-002
Aquitards
77:02F-037
Arid Climates
77:020-006
77:05G-026
Arid Lands
Arizona
Arkansas
Arsenic
77:03C-001
77:05G-026
77:060-001
77:02G-042
77:02J-015
77:02K-001
77:03A-001
77-.03F-070
77:03F-125
77:04A-030
77:02J-018
77: 05C-004
77:02G-069
Artesian Aquifers
77:02F-040
Artesian Heads
77:02F-015
Artificial Recharge
77:048-011
77:05A-007
77:058-018
Asphalt
77:05G-036
Atlantic Coastal Plain
77:058-019
Atmosphere
77:020-001
77:02F-030
Automatic Control
77 : 03T--104
Automation
77:03F-030
77:03F-104
77:03F-123
77:03F-125
77:04A-038
77:07B-005
Backwater
77:02E-001
Borehole Geophysics
77:02F-021
Bacteria
Boron
Barley
77:02G-105
77:050-002
77-.07B-034
77:026-070
77:058-056
77:02G-154
77:03F-130
Base Flow
Beans
77:02F-018
77:02G-025
77:05B-021
77:04A-006
77:056-017
Bed Load
77:02J-001
77:02J-002
77:02J-003
77:02J-011
Bottom Sediments
77:05G-033
Boundaries (Surfaces)
77:02F-004
77:02F-008
77:02F-009
77:02F-028
77 :08B-008
Boundary Layers
77:020-001
77:02F-010
77 :08B-003
Bromides
77 :05B-002
77:058-042
Beds
77:02J-002
Behavior
77:048-012
Beneficial Use
77:06E-013
Benefits
77:03F-005
77:04A-022
Bibliographies
77:04A-012
Bicarbonates
77:05B-005
Biochemical Oxygen Demand
77:05G-018
Biological Treatment
77:050-008
Biomass
77:021-018
Bluegrasses
77:03F-012
Border Irrigation
77:04A-017
77:04A-018
77:04A-019
Brucine Method
77:05A-009
Bulk Density
77:02G-079
77:02G-082
77:02G-151
77:02G-168
77:02J-010
77:03F-110
77:07B-023
Cadmium
77:020-088
77:021-013
77:021-019
77:05A-006
77:05B-056
77:050-005
77:07B-017
Cadmium Uptake
77 :05B-056
Calcareous Soils
77:02G-161
77:020-162
77:02K-001
77:05B-040
77:056-043
Calcite
Calcium
77:02F-030
77:02K-001
77 :02K-002
77:02F-016
77:02F-030
77-.02G-064
77:02G-066
77:02G-080
77:020-081
77:02G-106
287
-------
77:02G-107
77:02G-108
77:02G-155
77:02J-008
77:03F-032
77:04B-009
77:05B-005
77:05B-049
77:050-006
Calcium Carbonate
77:02G-100
77:02K-001
77:05G-001
Calcium Chloride
77:02G-004
77:02G-077
Calibrations
77:02G-047
77:05A-001
77:07B-029
California
Canada
77:02F-013
77:02G-038
77:02G-045
77:03F-120
77:04B-011
77:05A-007
77:056-014
77:05B-018
77:058-020
77:058-051
77:05G-010
77:06E-002
77:078-003
77:02F-021
77:05B-048
Canal Design
77:03F-002
Canal Linings
77:056-013
77:056-014
77:08A-001
Canal Seepage
77:03F-063
77:03F-095
Canals
Canopy
77:026-048
77:03F-005
77:08A-001
77:08B-005
77:086-007
77:02L-001
Capillary Action
77:02F-031
Capillary Conductivity
77:026-011
77:026-029
Capillary Water
77:026-011
77:02G-033
77:026-141
Carbon
77:026-156
77:026-166
77:07B-014
Carbonate Dioxide
77:02F-030
77:02K-002
Carbonate Rocks
77:02K-002
Carbonates
77:026-084
77:058-005
Carrots
77:03F-079
Cation Exchange
77:026-064
77:026-066
77:026-068
77:026-082
77:026-088
77:026-107
77:026-108
77:026-119
77:026-121
77:02G-155
77:058-033
77:056-034
77:078-012
77:078-031
77:07B-037
Cations
Caves
Cements
77:02F-016
77:026-004
77:026-057
77:026-106
77:026-107
77:026-108
77:03F-032
77:048-009
77:02F-030
77:02K-002
77:026-046
Center Pivot Systems
77:04B-015
Central United States
77:026-034
Centrifugation
77:026-083
Cesium
77:026-004
77:058-007
Channel Erosion
77:02J-043
77:04A-015
Channel Flow
77:02E-005
77:02G-142
77:04A-015
Channel Improvement
77:04A-015
Channels
Chelation
77:02F-011
77:02J-013
77:04A-015
77:088-003
77:08B-007
77:02J-024
Chemical Analysis
77:026-173
77:05A-009
77:05G-033
Chemical Oxygen Demand
77:02J-008
Chemical Potential
77:05A-009
Chemical Precipitation
77:026-015
77:02K-001
77:05B-001
77:058-023
Chemical Properties
77:026-047
77:02G-173
77:05A-009
77:058-007
77:056-033
Chemical Reactions
77:02K-005
77:05A-002
77:05E-002
Chemicals
Chemistry
77 :02E-004
77:02F-049
77-.03F-133
77:05A-002
77:05A-007
77:058-005
77:02F-030
77:026-004
77:026-083
77:02G-173
77:02K-002
77:058-023
Chiselling
77:02G-082
283
-------
Chlorides
77:02F-016
77:02G-004
77:02G-018
77:02G-023
77:02G-024
77:03F-045
77:03F-056
77.-05B-002
77:058-005
77:05B-015
77:05B-017
77:05B-039
77:056-050
Clay Loam
77.-02G-010
77:02G-012
77:02G-013
77:02G-017
77:02G-023
77:02G-024
77:021-002
Clay Minerals
77:02F-005
Clays
77:020-004
77:02G-004
77:02G-008
77:02G-027
77:02G-036
77:026-054
77:02G-064
77:02G-067
77:02G-088
77:02G-104
77:02G-121
77:02G-130
77:026-131
77:026-147
77:026-173
77:03F-095
77:040-005
77:050-001
77:076-006
Climates
77:02G-129
77:03F-043
77:04A-036
77:058-024
77:056-026
77:060-001
77:060-002
Climatology
77:020-006
77:03F-132
Clogging
Clovers
77:04A-035
77:056-035
77:07B-003
Cohesion
77 :02G-070
Cohesionless Soils
77:02J-003
Colorado
77:021-012
77:03F-098
77:05A-005
77:058-013
77:056-055
77:056-007
77:056-013
77:056-014
77:06E-010
77:06E-011
77:07B-035
Colorado River
77:02F-035
77:02G-042
77:05A-005
77:05B-013
77:056-013
77:056-014
77:06E-002
Columbia River
77:056-005
Compaction
77:02F-006
77:02F-013
Compressibility
77:02F-012
77:02F-014
77:02F-047
77:02F-048
Computer Models
77:020-005
77:02F-001
77:02F-019
77:02F-022
77:02F-025
77:02F-026
77 :02F-^31
77:026-014
77:026-027
Computers
Coastal Plains
77:056-002
77:058-026
77:050-001
77:086-009
Computer Programs
77:02E-002
77:02F-029
77:026-107
77:02J-014
77:02J-020
77:02J-038
77.-03F-007
77:03F-050
77.-03F-129
77:056-029
77:056-030
77:078-010
77:088-006
Concrete
77:02E-001
77:03F-072
77:048-
77:040-006
77:05B-047
77:08A-001
Conductivity
77:02F-021
77:02F-036
77:026-015
77:05A-007
Confined Water
77:02F-015
77:02F-023
77:02F-028
77:02F-052
Conjunctive Use
77:04A-001
77:04B-003
Conservation
77:056-024
Consolidation
77:02F-006
77:02F-013
Constraints
77:03F-018
77:048-006
77:048-008
77:056-018
Consumptive Use
77:021-002
Contour Farming
77:02E-004
Control
77:048-001
77:048-003
77:056-003
Convections
77:02F-007
77:02F-034
77:058-022
Conveyance Structures
77:03F-002
Cooling
Copper
Cores
Corn
77:020-010
77:05A-006
77:02G-126
77:056-033
77:020-011
77:02F-027
289
-------
77:02G-037
77:02G-046
77:02G-053
77:02G-105
77:02G-120
77:02G-141
77:02G-171
77:021-005
77:021-013
77:021-016
77:03F-019
77-.03F-023
77:03F-041
77:03F-055
77:03F-065
77 :03F-096
77:03F-098
77:03F-126
77:04A-031
77:056-030
77:05B-036
77:058-038
77:05B-039
77:058-042
77:05G-024
77:05G-039
Corn (Field)
77:020-005
77:020-009
77:02G-096
77:03F-006
77:040-005
77:058-004
Correlation Analysis
77:020-001
77:02F-003
77:02F-016
Cost Analysis
77:06C-002
Cost Comparisons
77:04A-022
77:06C-002
Cost Repayment
77:03F-135
Cost-Benefit Analysis
77:03F-135
Cost-Benefit Ratio
77:03F-001
Costs
77:03F-005
77:04A-022
77:048-002
77:048-003
77:046-004
77:04D-006
77:050-001
77:050-003
77:050-018
77:060-002
77:086-004
Cotton
77:021-007
77:021-017
77 :03C-001
77:03F-090
77:04A-029
77:05C-004
Crop Production
77:020-002
77:020-011
77:02F-027
77:02G-041
77:02G-053
77:02G-073
77:02G-096
77:02G-102
77:02G-104
77-.02G-109
77:02G-118
77:02G-136
77:02G-144
77:02G-150
77:021-001
77:021-007
77:021-009
77:021-011
77:021-013
77:021-014
77:021-016
77:02J-011
77:02L-001
77:03C-001
77:03C-002
77:03F-001
77:03F-004
77:03F-006
77:03F-012
77:03F-013
77:03F-014
77:03F-020
77:03F-026
77:03F-029
77:03F-033
77:03F-034
77:03F-035
77:03F-036
77:03F-037
77:03F-039
77:03F-040
77:03F-041
77:03F-042
77:03F-043
77:03F-044
77:03F-045
77:03F-046
77:03F-047
77:03F-048
77:03F-051
77:03F-052
77:03F-055
77 :03F-058
77:03F-061
77:03F-064
77:03F-065
77:03F-067
77:03F-069
77:03F-071
77:03F-075
77:03F-082
77:03F-085
77:03F-088
77:03F-090
77:03F-091
77:03F-098
77:03F-108
77:03F-110
77:03F-112
77:03F-117
77:03F-120
77:03F-121
77:03F-123
77:03F-126
77:03F-128
77:03F-129
77:03F-130
77:03F-131
77:03F-132
77:03F-135
77:03F-136
77:04A-031
77:04A-039
77:04A-040
77:05B-032
77:056-036
77:058-038
77:05C-001
77:05C-002
77:05C-004
77:050-001
77:05G-005
77:05G-011
77:05G-020
77:05G-022
77:05G-026
77:05G-028
77:05G-034
77:060-002
77:06E-013
77:078-003
77:076-014
77:076-019
77:076-036
Crop Response
77:020-002
77:020-005
77:02F-027
77-.02G-036
77:02G-053
77:02G-104
77:02G-120
77:02G-144
77:026-156
77 :02G-157
77:02G-166
77:02G-171
77:021-001
77:021-005
77:021-006
77 :02I-007
77:021-010
77:021-011
77:021-013
77:021-017
77:02L-001
77:03F-003
77 :03F-004
^ 77:03F-006
77:03F-011
290
-------
Croo Response
(cent.)
77:03F-012
77-.03F-013
77:03F-014
77:03F-022
77:03F-031
77:03F-033
77:03F-034
77:03F-035
77:03F-036
77:03F-037
77:03F-039
77:03F-041
77:03F-042
77:03F-044
77:03F-047
77:03F-054
77:03F-055
77:03F-058
77:03F-071
77:03F-082
77:03F-090
77:03F-112
77:03F-126
77:03F-130
77:04A-026
77:04A-039
77-.05B-028
77:05B-032
77:05G-022
77:07B-003
77:076-014
77:073-017
Curves
Demand
Crops
Crust
77:028-001
77 :02D-006
77:02E-004
77:020-005
77:02G-034
77:04D-005
77:058-004
77:06A-006
77:060-002
tests
77:02G-174
Cul t i val ?d Lands
77 : u?J-043
Cultivation
77:02G-007
77:02G-082
77-.03F-036
77:03F-087
77 :04A-040
Current Meters
77:078-030
Current (water)
77:02F-007
77:078-022
Dams
77:02F-037
77:02F-047
77:02F-048
77:026-012
77:02G-013
77:02G-074
77:02G-095
77:046-007
77:040-006
77:02F-008
77:02F-015
Darcys Law
77:02F-001
77:02F-002
77:02F-028
77:02F-052
77:02G-030
77:026-032
Data
77:03F-018
77:04A-001
77:048-004
Data Collections
77:02G-033
77:02J-003
77:02L-001
77:058-005
77:078-005
77:078-005
77:078-033
77:088-016
Data Processing
77:02D-001
77:02F-016
77:02F-036
77:058-008
Dead Storage
77:02J-015
Decision Making
77:02J-015
77:04A-001
77 :04B-004
77:05G-003
77:068-002
Decomposing Organic Matter
77:02G-099
Deep Percolation
77:05A-005
Deformation
77 :02F-006
77:02F-014
Degradation (decomposition)
77 :05B-009
Degradation (slope)
77:02J-043
Degradation (stream)
77:02J-043
Demonstration Watersheds
77:02J-011
77:058-004
Denitrification
77:02G-053
77:02G-062
77:02G-063
77:02G-103
77:02G-105
77:02G-113
77:02G-120
.77:020-165
77:026-170
77:021-003
77:02K-005
77:05A-002
77:05B-014
77 :05B-025
77:058-053
77:05E-002
77:07B-015
77:078-016
77:07B-032
. 77:078-034
Density
77:02F-028
Deposition
77:02J-013
Deposition (sediments)
77:040-004
Depth
77:02F-004
77:02F-006
77:02G-007
77:02G-077
77:02G-082
77 :08B-004
77:088-009
Desalination
77:03A-001
77:05G-007
77:05G-014
Desalination Plants
77 :05G-018
Deserts
Design
77:060-001
77:03F-021
77:08B-007
77 :08B-010
Dewatering
77 :04B-006
Differentiation
77:026-095
291
-------
Diffusion
77:02F-050
77:02G-012
77:02G-013
77:02G-019
77:02G-054
77.-02G-077
77:026-078
77:056-022
Diffusivity
77:02F-046
77:02G-009
77:02G-019
77:02G-030
77:026-051
77:026-056
77:02G-081
Dilution Effects
77:02G-083
Dimensional Analysis
77:08B-002
77:08B-013
Discharge
77:02F-008
Discharge (Water)
77:02F-004
77:02F-025
77:02F-047
77:02F-048
77:02F--052
77:03F-021
77:04i3-006
77:04D-003
77:05A-001
77:05G-031
77:088-002
77:08B-OOl
77:08B-011
77:088-016
Discharge coefficient
77:08B-002
77:08B-005
77:08B-011
77:08B-016
Discharge Measurement
77:04A-012
77:08B-011
Discharge Sediments
77:02J-001
Discount Rates
77:04B-008
Dispersion
77:02F-024
77:02F-033
77 :02G-018
77:026-022
77:026-023
77:02G-024
77:026-028
77:02G-054
77:02G-124
77:026-143
77:026-175
77.-05B-002
77 :05B-008
77:058-050
Dissolved Oxygen
77 :02F-040
77:021-018
77:050-002
Dissolved Solids
77:02F-049
77:05A-003
77:056-028
Distribution
77:05A-006
Distribution Patterns
77:026-010
77:04A-023
77:04D-007
Ditches
Diurnal
77:04A-023
77:026-007
Diversion
77:048-005
Dolomite
77:02K-002
Domestic Wastes
77:050-002
Downstream
77:04A-001
77:056-003
77:056-032
Drainage
77:02F-032
77:02F-045
77:02F-052
77 :026-025
77:026-045
77:026-054
77:02G-060
77:026-065
77:02G-071
77:026-072
77:026-073
77:026-082
77 :026-116
77:026-117
77:026-118
77:02G-122
77:026-125
77:02G-126
77 :02J-013
77:02J-036
77:02J-043
77:03A-001
77:03F-037
77:03F-049
77:03F-065
77:03F-100
77:04A-002
77:040-003
77:05B-002
77:05B-027
77:05B-046
77:05B-056
77:050-001
77:056-001
77:056-019
77:068-001
77:08B-009
Drainage Area
77:056-018
Drainage Districts
77:026-045
77:026-072
77:02G-073
Drainage Effects
77:026-073
77:026-116
77:02G-117
77:03F-037
77:03F-049
77:03F-065
77:03F-100
Drainage Engineering
77:026-072
77:026-092
77:026-116
Drainage Patterns (eeologic)
77:040-003
Drainage Practices
77:026-045
77:026-072
77:026-073
77 :026-092
77:026-116
77:026-118
77:026-122
77:04B-002
77:06E-001
Drainage Programs
77:026-073
Drainage Systems
77:02F-052
77:02G-071
77:026-072
77:026-073
77:026-092
77:026-116
292
-------
Drainage Systems
(cont.)
77:02G-118
77-.02G-122
77:03F-049
77:040-005
Drainage Water
77:021-004
77:03A-001
77:03F-049
77:056-040
77:05G-001
Drains
Drawdown
Drilling
77:02F-004
77:020-072
77-.02G-092
77:026-122
77:08B-008
77:02F-001
77:02F-004
77:02F-006
77:02F-013
77:02F-019
77:02F-023
77:02F-037
77:02F-047
77:02F-048
77:048-007
77:05G-017
77:08B-004
Drilling Fluids
77:05G-017
Drops (Structures)
77:08B-001
Droughts
Dry Beds
77:021-001
77:03F-006
77:02G-029
Dry Farming
77:020-002
77:021-002
77:03F-036
Drying
77:020-074
Dynamics
77:07B-022
Earth-Water Interfaces
77:058-023
Economic Development
77:03F-135
Economic Efficiency
77 :03F-018
77:04A-001
1 77:048-001
77:046-004
77 :04B-008
77:05G-003
77:05G-018
Economic Feasibility
77 :03F-005
77:04A-022
Economic Impact
77:03F-135
Economics
77:02G-117
77L02G-118
77:02J-027
77:02J-045
77:03F-027
77:03F-063
77:03F-068
77:03F-073
77:03F-074
77:03F-109
77:03F-113
77:03F-134
77:03F-135
77:04A-031
77:04A-033
77:046-002
77:050-001
77:05G-011
77:05G-012
. 77:05G-013
77:06A-002
77:06C-001
77:06C-002
77:06E-007
77:08B-006
77:08C-001
Ecosystems
77:021-018
Education
Dune Sands
77:03F-004
Dupuit-Forchheimer Theory
77:02F-008
77:02F-018
Effects
77:05G-024
77:02G-005
77:031-003
77:04B-002
Dyes
77:078-001
Dynamic Programming
77-.03F-003
77:05G-003
Efficiencies
77:03F-002
Effluent Limitation
77:05G-021
Effluents
77:02G-015
77:02G-022
77:02K-005
77:05A-001
77:05B-005
77:05B-056
77:050-007
77:05E-001
Elastic Deformation
77:02F-006
Electrical Conductance
77:02G-015
77:026-083
77:058-003
77:050-001
77:050-002
77:07B-006
Electrical Engineering
77 :07B-030
Electrical Equipment
77:03F-106
77.-03F-107
77:05A-009
77 :07B-005
Electrical Power
77:03F-106
77:03F-107
Electrical Power Production
77:03F-106
77:03F-107
Electrical Properties
77:05E-002
Electrical Resistance
77:02F-021
77:02F-036
Electricity
77:03F-106
77:03F-107
Electrochemistry
77:05A-009
Electrodes
77:05A-009
Electrolytes
77 :02F-005
77:02F-176
Electronic Equipment
77:07B-005
Electronics
Emulsions
77-.07B-030
77:038-001
293
-------
77:03F-134
77:03F-136
77:04B-015
77:040-002
77:080-001
Energy Equation
77:088-002
Engineering
. 77:07B-030
Environment
77:06E-014
Environmental Control
77:03F-027
77:04A-021
77:06E-014
Environmental Effects
77:02G-153
77:02J-004
77:04A-021
77:06A-005
77:06B-002
Environmental Quality
77:03F-132
Environmental Quality
Management
77:020-153
Equations
77
77:
77
77
77
77;
77:
77
77
77
77:
77:
77
77:
77:
77:
77
77:
77:
77:
77:
77:
77:
77:
77:
77;
77;
77:
77:
77:
77:
77:
77;
02B-002
02D-001
02E-001
02F-002
02F-003
02F-004
02F-006
02F-007
02F-008
02F-012
02F-014
02F-015
02F-018
02F-023
02F-037
02F-045
02F-046
02F-047
02F-048
02F-052
02G-009
02G-012
02G-019
02G-020
02G-021
02G-026
02G-027
02G-028
02G-029
02G-048
02G-056
02G-077
02G-079
77:02G-095
77:02G-124
77:02G-125
77:02G-138
77:026-139
77:02J-010
77:02J-013
77:02J-041
77:02J-042
77:03F-001
77:03F-002
77:03F-003
77:03F-005
77:03F-021
77:04A-001
77:04A-022
77:04A-037
77:04B-001
77:04B-003
77:04B-006
77:048-007
77:048-008
77:04B-012
77:040-006
77:050-003
77:05G-003
77:05G-018
77:07C-002
77:08B-002
77:08B-011
77:088-016
Equipment
77:02F-036
77:02G-001
77:02J-002
77:02J-011
77:03F-089
77:07B-005
77:07B-030
Erodibility
77:02G-173
Erosion
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02B
:02G-
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
:02J
001
079
001
004
010
Oil
012
013
014
016
020
022
023
025
026
027
028
029
030
-033
034
-035
-036
-037
77:02J-038
77:02J-040
77:02J-041
77:02J-042
77:02J-043
77:02J-044
77:02J-046
77 :03F-020
77:03F-024
77:03F-051
77:03F-052
77:03F-062
77:03F-087
77:04A-021
77:040-001
77:040-006
77:05B-030
77:05G-022
77:05G-023
77:05G-025
77:06A-001
77:06E-007
77:078-011
Erosion Rates
77:02J-001
77:02J-010
77:02J-012
77:02J-028
77:02J-040
Estimating
77:02D-001
77:02G-011
77:02J-015
77:02J-041
77:03F-005
77:03F-018
Eutrophication
77:056-046
77:05C-003
Evaluation
77:02F-003
77:02G-001
77 :02J-004
77:03F-001
77:03F-005
77:05B-005
Evaporation
77:020-001
77:020-004
77:020-009
77:020-010
77:020-011
77 :02G-049
77:02G-060
77:02G-082
77:02G-137
77 :02L-001
77:03F-038
77:03F-086
77:03F-097
77.-05B-021
Evaporation Pans
77 :03F-001
294
-------
Evapotranspiration
77:020-001
77:020-003
77:020-005
77:020-006
77:020-007
77:020-009
77:020-008
77:02G-014
77:02G-032
77:02G-049
77:020-096
77:020-129
77-.02G-142
77:021-016
77:03F-001
77:03F-008
77:03F-011
77:03F-023
77:03F-037
77:03F-039
77:03F-040
77:037-054
77:03F-094
77:03F-115
77:03F-126
77:04B-013
77:058-021
77:05B-024
77:07B-036
Expansive Clays
77:05B-007
Exploration
77:088-004
Farm Equipment
77:04B-015
Farm Management
77:02E-004
77-.02L-001
77:040-006
77:05G-023
Farm Ponds
77:050-001
Farm Wastes
77:028-001
77:058-031
77:05G-023
Farms
77:05B-031
Feasibility Studies
77:04A-022
Federal Government
77:06E-013
Federal Reclamation Law
77:050-021
Federal Water Pollution
Control Act
77:050-021
77:050-023
Fertilization
77:02G-009
77:02G-037
77:02G-038
77:020-053
77:020-059
77:020-062
77:02G-104
77:020-105
77:020-120
77:020-147
77:020-149
77:020-150
77:020-157
77:020-163
77:020-171
77:021-012
77:02J-008
77:02J-046
77:03F-004
77:03F-013
77 :03F-014
77:03F-031
77:03F-032
77:03F-033
77:03F-043
77:03F-047
77:03F-056
77:03F-090
77:03F-091
77:03F-102
77:03F-108
77:03F-109
77:03F-127
77:03F-129
77:03F-130
77:03F-131
77:03F-132
77:048-013
77:05A-003
77:05B-014
77:058-017
77:058-035
77:058-038
77:058-041
77:058-043
77:058-055
77:050-009
77:050-004
77:050-005
77:050-022
77:050-027
77:078-014
77:078-015
77:078-033
77:078-035
Fertilizers
77:028-001
77:020-036
77:020-037
77:020-038
,s/ ' 77:020-040
' , /' 77-.02G-053
77:020-057
77:020-059
77:020-062
77:020-096
77:020-097
77:020-104
77:020-
77:020-
77:02G-
77:026-
77:020-
77:020-
77:020-
77:020-
77:020-
77:020-
77:020-
77:021-
77:02J-
77:02J-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:048-
77:048-
77:05B-
77:058-
77:058-
77:058-
77:058-
77:058-
77:05B-
77:058-
77:05B-
77:058-
77:05C-
77:050-
77:05G-
77:050-
77:050-
77:050-
77:078-
77:078-
77:078-
77:078-
77:07B-
105
120
134
135
147
149
150
157
163
171
175
012
008
046
013
014
022
031
032
033
043
045
047
056
057
078
102
108
109
116
127
129
130
131
132
013
015
010
Oil
014
025
035
038
041
042
043
055
005
004
005
Oil
023
027
014
015
018
033
035
Field Crops
Filters
77:02E-004
77:03F-029
77:040-004
77:050-004
77:078-001
295
-------
Filtration
77:02G-019
77:03F-030
77:04A-035
77:050-004
Financing
77:060-002
Finite Difference Analysis
77:020-175
Finite Element Analysis
77:02F-006
77:02F-012
77:02F-026
77: 02G-128
77:04B-001
77:05B-008
Fissures (Geologic)
77:02F-047
77:02F-048
Flood Control
77:04A-022
77:05B-027
77:056-032
77:068-002
Flood Irrigation
77:03F-123
77:04A-026
Flood Protection
77:04A-022
Florida
Flow
77:03F-091
77:05B-027
77:05B-041
77:05G-017
77:02E-001
77:02E-005
77:02F-002
77:02F-004
77:02F-012
77:02F-014
77:02F-017
77:02F-019
77:02F-025
77:02F-047
77:02F-052
77:02G-012
77:02G-030
77:02G-031
77:02G-142
77:03F-005
77:03F-089
77:04A-023
77:04B-001
77:04D-007
77:05B-021
77:078-030
77:08B-001
77:08B-003
77:088-007
77:088-008
77:088-016
Flow Characteristics
77 :02F-040
Flow Measurement
77:03F-089
77:04A-011
77:04A-012
77:07B-022
77:078-024
77:078-025
77:078-026
77:078-027
77:078-028
77:078-029
77:088-007
Flow Nets
77:02F-008
Flow Profiles
77:02E-001
Flow Rates
77:04A-011
77:04A-012
77:04A-037
77:05G-035
77:07B-028
77:08B-012
77:08B-014
77:088-015
Flow Resistance
77:03F-087
Flowering
77:021-001
Flowmeters
77:088-011
77:088-016
Fluctuations
77:02F-020
77 :02F-032
77:05B-020
Fluid Friction
77:02F-007
Fluid Mechanics
77:02F-002
77:02F-007
77:040-007
Flumes
77:04A-011
77:05A-001
77:078-024
77:078-027
77:078-029
77:088-007
Fluorescent Dye
77:078-001
Fly Ash
77:02G-168
Fluorides
77-:05B-005
Forecasting
77:02F-010
77:02G-005
77:02J-013
77:03F-086
77:048-005
77:040-006
77:058-021
Foreign Countries
77:020-004
77:02D-006
77:020-008
Foreign Research
77:020-004
77:020-006
77:020-008
77:02F-025
77:02G-033
77:05A-003
77 :07B-002
Forest Watersheds
77:02G-014
Formulas
77:02B-002
Fraction Permeability
77:02F-012
Free Surfaces
77:02F-009
Freezing
77:02C-001
Frequency Analysis
77:048-002
Friction
77:08B-002
77:088-014
77:08B-015
Fringe Vvater
77:02G-033
Frost
77:02C-001
Frost Action
77:020-001
Frost Protection
77 :02D-010
Frozen Ground
77:02C-001
Frozen Soils
77:02C-001
Fruit Crops
77 :02D-010
77 :02G-049
296
-------
Furrow Irrigation
77:026-037
77:02J-010
77:03F-023
77:03F-042
77:03F-062
77:03F-065
77:03F-083
77:03F-087
77:03F-120
77:03F-123
77:04A-004
77:04A-020
77:04A-037
77:04A-038
77:04A-040
77:058-042
77:050-005
77:06C-002
77:078-021
1
Furrow Systems
77:04A-038
77:04A-040
Furrows
Gages
77:03F-087
77:03F-089
Gate Control
77:086-003
Gates
77:04A-038
77:08B-003
Geochemi stry
77:02F-016
77:05A-006
77:078-002
Geohydrologic Units
77:02F-010
Geology
77:02F-021
77:058-049
Geomorphology
77-.02J-043
77:02K-002
Geophysics
Georgia
77:02F-005
77-.02F-021
77:022-003
Germination
77:021-001
77:03C-001
77:03F-042
77:03F-044
Glacial Drift
77:02F-021
77:058-049
77:050-005
Glucose
77:02G-113
77:02G-161
77:02G-162
Government Interrelations
77:05G-021
Governments
77:03F-135
Gradually Varied Flow
77.-02E-001
Grain Sorghum
77:020-002
77:04A-039
77:04A-040
77:05G-039
Grain Yield
77:05G-039
Grain (Crops)
77:021-016
77:03F-006
Graphical Analysis
77.-02E-001
77:02F-008
77:02F-037
77:048-007
Graphical Methods
77:02E-001
Grassed Waterways
77;02E-005
77:04D-004
77:05G-002
Grasses
77:020-006
77:03F-014
77:04D-004
Gravimetric Analysis
77:02G-047
Gravimetry
77:02G-047
Gravitational Water
77:04A-027
Greenhouses
77:020-008
77:021-009
77:021-013
77:058-032
' ' -/
Groundwater
77:02F-005
77:02F-007
77:02F-011
77:02F-014
77:02F-016
77:02F-017
77:02F-018
77:02F-019
77:02F-020
77:02F-021
77:02F-023
77:02F-024
77:02F-025
77:02F-026
77:02F-027
77:02F-030
77:02F-032
77:02F-033
77:02F-034
77:02F-035
77:02F-036
77:02F-038
77:02F-039
77:02F-040
77:02F-042
77:02F-043
77:02F-044
77:02F-045
77:02F-046
77:02F-049
77:02F-050
77:02F-051
77:02G-023
77:02G-024
77:02G-025
77:020-030
77:026-048
77:02G-054
77:020-124
77:02J-011
-177:02K-002
77:03F-056
77:04A-001
77:04A-003
77:048-003
77:04B-004
77:048-005
77:048-006
77:04B-008
77:048-010
77:048-011
77:048-012
77:048-013
77:048-014
77:040-001
77:05A-005
77:05A-006
77-.05A-007
77:058-010
77:058-016
77:058-017
77:05B-018
77:058-019
77:058-020
77:058-021
77:058-022
77:05B-024
77.-05B-031
77:058-034
77:058-045
77:05B-056
77-.05D-009
77:056-017
77:050-022
77:05G-028
77:056-038
77:078-002
77:078-010
297
-------
Groundwater Barriers
77:048-011
Groundwater Basins
77:02F-027
77:02F-035
77:02F-043
77:02F-044
Groundwater Flow
77:02F-028
Groundwater Mining
77:02F-044
Groundwater Movement
77:02F-001
77:02F-002
77:02F-003
77:02F-004
77:02F-007
77:02F-009
77:02F-010
77:02F-011
77:02F-014
77:02F-015
77:02F-017
77:02F-018
77:02F-019
77:02F-020
77:02F-022
77:02F-025
77:02F-026
77:02F-029
77:02F-030
77:02F-033
77:02F-034
77:02F-038
77:02F-039
77:02F-040
77:02F-045
77:02F-047
77:02F-048
77:02F-049
77 :02F-050
77:02G-011
77:02G-023
77:02G-024
77:02G-025
77:02G-030
77:02G-048
77:05A-007
77:058-008
77.-05B-016
77:058-017
77:05B-018
77:058-019
77:058-021
77:058-045
Groundwater Potential
77:02F-021
77:02F-027
77:02F-043
77:088-008
Groundwater Recharge
77:02F-004
77:02F-020
77:02F-031
77:02F-032
77:02F-035
77:02F-044
77:04B-011
77:05A-007
77:058-018
77:05B-019
Groundwater Resources
77:02F-016
77:02F-020
77:02F-021
77:02F-027
77:02F-035
77:02F-038
77:02F-039
77:02F-042
77:02F-043
77:02F-044
77:02F-050
77:02F-051
77:048-001
77:048-013
Growth Rates
77:050-002
Growth Stages
77:021-010
77:021-011
Gullies
77:02J-043
Gully Erosion
77:040-001
Gypsum
Halides
77:05G-001
77:05B-002
Hardness (Water)
77:02F-030
77:058-005
Hawaii
Hazards
77.-03F-001
77:058-009
77:05B-031
Head Loss
77:088-002
77:088-014
77:088-015
Heat
77:026-051
Heat Flow
77:020-008
77:02F-034
Heat Pollution
77:058-007
Heat Transfer
77:02F-007
77:02F-034
77:02G-006
77:058-022
Heated Water
77 :02F-034
77:058-002
Heavy Metals
77:02G-067
77:02G-090
77:021-013
77:021-019
77:02J-038
77.-02K-003
77:05A-006
77 :05B-023
77:058-045
77:050-005
77:078-017
Height
77:021-011
Herbicides
77:03F-020
77:03F-098
77:03F-133
77:058-006
77:058-009
77:05B-034
77:05G-002
Herbigation
History
77:03F-133
77:02J-043
Horizontal Infiltration
77:02G-056
Hortans Law
77:02G-028
Humid Areas
77:02G-007
Humid Climates
77 :02G-007
Hydraulic Conductivity
77:02B-002
77:020-004'
77:020-009
77:02D-011
77:02F-011
77:02F-014
77:02F-022
77:02F-028
77:02F-029
77:02F-032
77:02F-033
77:02F-036
77:02F-037
77:02F-045
77:02F-049
293
-------
Hydraulic Conductivity
(cont.)
77:02G-002
77:02G-009
77:02G-010
77:020-016
77:02G-017
77:02G-023
77:02G-024
77:02G-025
77:02G-027
77:02G-030
77:02G-031
77:02G-032
77:02G-033
77:02G-035
77:02G-043
77:02G-046
77:02G-061
77:02G-080
77:02G-081
77:02G-092
77:02G-115
77:02G-125
77:026-126
77:02G-127
77:026-128
77:026-168
77:026-174
77:026-175
77:026-176
77:03F-010
77:03F-011
77:03F-095
77:04A-023
77:04A-025
77:043-006
77:04B-007
77:04D-003
77:058-016
77:08B-008
Hydraulic Design
77:04A-013
77:04A-014
77:08B-006
77:08B-010
77:088-012
77:088-013
77:086-014
77:088-015
Hydraulic Gradient
77:02F-046
77:026-176
Hydraulic Jump
77:088-001
Hydraulic Models
77:02G-033
77:04D-004
Hydraulic Properties
77:02F-004
77:02F-022
77:02F-047
77:02F-048
77:026-031
77:026-032
77:02G-081
77:026-082
77:026-176
Hydraulic Structures
77:02F-015
Hydrographs
Hydraulics
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02E-001
:02E-005
.-02F-011
:02F-052
:02J-003
:04A-011
:04A-013
:04A-014
:04A-015
:04A-024
:04A-027
:04B-012
:04D-007
:05A-001
:05B-047
:05G-003
:07B-027
:08B-001
:08B-002
:08B-003
:08B-005
:08B-006
:08B-007
:08B-009
:08B-010
:08B-011
:08B-012
:08B-013
:08B-014
:08B-015
-.08B-016
77:028-002
77:02F-046
77:02J-007
77:058-027
77:07B-005
Hydrography
77:040-003
Hydrologic Aspects
77:020-001
77:026-014
77:04A-022
Hydrologic Budget
77:02G-032
Hydrologic Data
77:02J-004
77:078-005
Hydrologic Properties
77:02F-036
77:02J-004
Hydrologic Systems
77:026-014
Hydrology
Hydrodynamics
77:02F-011
77:02F-038
77:026-023
77:02G-024
77:026-111
77:04A-019
77:058-034
77:056-047
Hydrogen
77:058-029
Hydrogen Ion Concentration
77:02K-002
77:05A-006
77:050-002
Hydrogeology
77:02F-003
77.-02F-010
77:02F-021
77:02F-029
77:02F-030
77:056-019
Hydrograph Analysis
77:02E-005
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02E-002
:02E-003
:02E-005
:02F-007
:02F-014
:02F-017
:02F-018
:02F-025
:02F-026
:02F-030
:02F-036
:02F-045
:02F-049
:02G-014
:026-025
:02G-031
:02G-093
:026-128
:026-142
:02J-010
:02J-020
:04B-002
:04B-005
:04B-011
:04D-003
: 040-006
:058-018
:05B-019
:05B-027
:056-004
:056-038
:05G-040
:06E-001
:07B-005
:07B-030
Hydrometry
77:026-091
299
-------
Hysteresis
Ice
Idaho
Illinois
Illite
77:020-001
77:02G-013
77:02G-030
77:02G-033
77:02G-035
77:02G-065
77:020-074
77:02G-094
77:02C-001
77:02E-002
77:02F-041
77:02J-011
77:03B-001
77:03F-042
77:04A-006
77:05B-035
77:026-113
77:050-001
77:02G-004
Iinmiscibility
77:026-083
Immobilization
77:02G-104
Impact (Rainfall)
77:026-050
77:026-079
77:02J-001
Impervious Soils
77:05D-001
Impoundment
77:088-009
Incentives
Income
Indexing
Indiana
77:056-024
77:03F-018
77:020-007
77:03F-024
Industrial Plants
77:05A-001
Industrial Wastes
77:050-002
Infiltration
77:028-002
77:02F-011
77:02F-025
77:02F-031
77:026-002
77:026-011
77:02G-014
77:02G-017
77:026-018
77:026-027
77:026-028
77:026-029
77:02G-030
77:026-032
77:026-035
77:026-046
77:026-048
77:02G-050
77:02G-056
77:026-058
77:026-071
77:026-075
77:026-076
77:026-082
77:02G-087
77:026-093
77:026-095
77:026-123
77:026-127
77:026-128
77:026-137
77:026-138
77:026-139
77:026-140
77:026-141
77:026-142
77:021-008
77:04A-017
77:04A-023
77:04A-036
77:05B-008
77:056-029
77:050-004
77:05E-002
77:078-024
77:07C-002
Infiltration Rates
77:026-028
77:026-029
77:02G-050
Inflow
77:02F-008
77:02J-044
77:04A-003
77:056-031
77:088-008
77:088-009
Infrared Radiation
77:03F-082
Injection
77:056-036
Injection Wells
77:048-011
77:058-022
77:05E-001
77:05G-017
Input-Output Analysis
77:020-005
77:04B-012
Instrumentation
77:02G-016
77:026-047
77:02J-011
77:02L-001
77:05A-001
77:078-002
77:078-030
77:088-007
Instruments
77:078-026
Inter-Basin Transfers
77:04A-022
77:048-005
Interfaces
Iodine
77:05B-023
77:026-054
Iodine Radioisotopes
77:026-054
Ion Exchange
77:026-077
77:026-081
77:026-106
77:050-005
77:056-034
Ion Transport
77:058-050
Ions
Iowa
77:02F-016
77:02F-040
77:026-080
77:026-084
77:026-101
77:02K-001
77:058-050
77:020-001
77:02G-119
77:02J-040
77:02J-043
77:02J-046
77 :05B-004
77:07B-020
Iron
77:026-086
77:05A-002
77:05A-006
77:058-026
Irrigated Land
77:02K-005
77 :03C-001
77:03F-007
77 :03F-057
Irrigation
77:02F-027
77:02F-041
77:02F-043
77:02F-044
300
-------
Irrigation
(cont.}
77:026-006
77:02G-015
77:020-026
77.-02G-037
77:02G-039
77:02G-041
77-.02G-043
77:02G-048
77:02G-049
77:02G-055
77:026-058
77:026-061
77:026-096
77:026-103
77:02G-115
77:026-123
77:026-126
77:02G-135
77:026-136
77:026-144
77:026-147
77:02G-152
77:02G-171
77:026-175
77:021-003
77:021-007
77:021-010
77:02J-010
77:02J-014
77:02J-037
77:02K-005
77:03A-001
77:030-001
77:03C-002
77:03F-001
77:03F-002
77:03F-007
77:03F-009
77:03F-010
77:03F-011
77:03F-019
77:03F-023
77:03F-034
77:03F-035
77:03F-036
77:03F-037
77:03F-040
77:03F-042
77:03F-044
77:03F-045
77:03F-050
77:03F-054
77:03F-056
77:03F-059
77:03F-060
77:03F-061
77:03F-062
77:03F-064
77:03F-065
77:03F-067
77:03F-069
77:03F-071
77:03F-073
77:03F-074
77:03F-075
77:03F-077
77:03F-078
77:03F-079
77 :03F-080
77:03F-081
77:03F-082
77:03F-084
77:03F-085
77:03F-089
77:03F-090
77:03F-091
77 :03F-092
77 :03F-094
77:03F-096
77:03F-099
77:03F-100
77:03F-102
77:03F-103
77:03F-104
77.-03F-105
77:03F-106
77:03F-107
77:03F-113
77:03F-114
77:03F-115
77:03F-116
77-.03F-118
77:03F-119
77:03F-121
77:03F-122
77:03F-123
77:03F-124
77:03F-125
77:03F-133
77:03F-134
77:03F-135
77:04A-001
77:04A-002
77:04A-006
77:04A-008
77:04A-009
77:04A-010
77:04A-012
77:04A-013
77:04A-014
77:04A-018
77:04A-019
77:04A-020
77:04A-021
77:04A-025
77:04A-027
77:04A-028
77:04A-030
77:04A-034
77.-04A-035
77:04A-036
77:04A-042
77:04B-009
77:04B-011
77:04D-005
77 :05A-004
77:058-006
77:05B-011
77:056-017
77:056-024
77:05B-035
77:05B-042
77:058-050
77:056-055
77:05C-001
77:05C-002
77:05C-005
77:050-001
77:05D-009
77:05G-003
77:05G-005
77:056-007
77:05G-008
77:056-010
77:056-011
77:056-012
77:05G-013
77:056-018
77:056-020
77:056-021
77:05G-022
77:056-027
77:056-028
77:056-029
77:056-030
77:056-037
77:05G-040
77:06A-002
77:06A-006
77:060-001
77:060-002
77:06E-004
77:06E-005
77:06E-012
77:07B-010
77:078-035
77:08A-001
77:088-006
77:070-001
Irrigation Canals
77:026-048
77:056-036
Irrigation Design
77:026-087
77:026-141
77:03F-029
77:03F-068
77:03F-081
77:03F-100
77:03F-103
77:04A-013
77:04A-014
77:04A-017
77:04A-024
77:04A-032
77-.04A-038
77:088-006
77:086-010
77:08B-012
77:088-013
77:086-014
77:08B-015
Irrigation Districts
77:03F-005
77:04A-005
77:056-021
Irrigation Ditches
77:026-048
77:03F-089
Irrigation Effects
77.-02F-041
77:02G-006
77:026-103
301
-------
Irrigation Effects
(cont.)
77:02G-115
77:020-136
77:020-144
77:020-145
77:02G-147
77:020-152
77:020-171
77:021-007
77:03F-004
77:03F-010
77:03F-011
77:03F-019
77:03F-034
77:03F-035
77:03F-036
77:03F-037
77:03F-042
77:03F-056
77:03F-059
77:03F-060
77:03F-061
77:03F-064
77:03F-065
77:03F-078
77:03F-080
77:03F-086
77:03F-096
77:03F-099
77:03F-100
77:03F-102
77:03F-112
77:03F-115
77:03F-116
77:03F-119
77:03F-126
77:04A-021
77:04A-030
77:058-003
77:05B-010
77:058-042
77:058-044
77:058-055
77:050-001
77:05D-009
77:050-012
77:050-019
77:050-020
77:050-027
77:050-029
77:050-030
77:050-037
77:06E-012
77:07B-010
77:078-015
77:078-021
77:078-035
Irrigation Efficiency
77:020-042
77:020-044
77:03A-001
77:03F-008
77:03F-009
77:03F-019
77:03F-021
77:03F-028
77:03F-036
77:03F-054
77:03F-056
77 :03F-059
77:03F-060
77:03F-062
77:03F-067
77:03F-069
77:03F-071
77:03F-075
77:03F-076
77:03F-078
77 :03F-089
77:03F-092
77:03F-094
77:03F-097
77:03F-100
77:03F-101
77:03F-104
77:03F-105
77:03F-113
77:03F-117
77:03F-121
77:03F-122
77:03F-123
77:03F-124
77:03F-125
77:04A-003
77:04A-004
77:04A-007
77:04A-008
77:04A-010
77:04A-012
77:04A-020
77:04A-027
77:04A-029
77:04A-032
77:04A-034
77:04A-035
77:04A-037
77:04A-038
77:048-015
77:050-022
77:078-036
77:088-010
77:08B-012
77:08C-001
Irrigation Engineering
77:03F-068
77:03F-089
77:04A-013
77:04A-018
77:04A-019
77:04A-020
77:04A-027
77:04A-032
77:04A-033
77:058-047
77:050-001
77:088-010
77:088-012
77:088-013
77:088-014
77:086-015
Irrigation Methods
77:03F-083
77:03F-094
77:03F-097
77:088-010
Irrigation Practices
77:020-005
77:020-055
77:020-061
77:020-087
77:020-136
77:02J-011
77:02L-001
77.-03F-004
77:03F-009
77:03F-010
77:03F-011
77:03F-019
77:03F-021
77:03F-028
77.-03F-029
77:03F-030
77:03F-042
77 :03F-044
77:03F-050
77:03F-068
77:03F-069
77:03F-070
77:03F-073
77:03F-074
77:03F-076
77:03F-077
77 :03F-078
77:03F-081
77:03F-082
77:03F-083
77:03F-084
77:03F-085
77:03F-086
77:03F-091
77:03F-092
77:03F-094
77:03F-097
77:03F-098
77:03F-101
77:03F-102
77:03F-103
77:03F-104
77:03F-105
77:03F-106
77:03F-107
77:03F-113
77:03F-114
77:03F-115
77:03F-118
77:03F-121
77:03F-122
77:03F-124
77:03F-125
77:03F-133
77:04A-006
77:04A-010
77:04A-018
77:04A-019
77:04A-021
77:04A-024
77:04A-025
77:04A-026
77:04A-027
77:04A-028
77:04A-029
77:04A-031
77:04A-033
77:04A-034
77:04A-035
302
-------
Irrigation Practices
(cont.)
77:04A-036
77:04A-038
77:04B-009
77:04B-015
77:058-042
77.-05C-002
77:050-013
77:05G-021
77:05G-022
77:05G-038
77:06C-002
77:076-021
77:07B-035
77: 09C-001
77:06E-012
Irrigation Return Flow
77:05G-021
Irrigation Systems
77:02F-036
77:02G-037
77:02G-061
77:02G-087
77:02G-123
77:02G-141
77:02J-010
77:03F-003
77:03F-005
77:03F-009
77:03F-010
77:03F-011
77:03F-021
77:03F-023
77:03F-028
77:03F-029
77:03F-030
77:03F-057
77:03F-061
77:03F-067
77-.03F-068
77:03F-070
77:03F-076
77:03F-079
77:03F-080
77:03F-081
77:03F-083
77:03F-084
77:03F-086
77:03F-090
77-.03F-091
77:03F-092
77 :03F-101
77:03F-103
77:03F-104
77:03F-114
77:03F-118
77:03F-121
77:03F-122
77:03F-124
77:03F-125
77:03F-127
77:03F-136
77:04A-003
77:04A-008
77-04A-010
77:04A-013
77:04A-014
77:04A
77:04A
77:04A-
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:04A
77:05B
77:05G
77:056
77:056
77:06C
77:06C
77:08A
77:08B
77:08B
77:08B
77:09C
018
019
020
024
026
027
028
029
033
034
035
036
038
039
040
041
010
013
022
035
001
-002
.-001
-012
-014
015
:-001
Isotope Studies
77:03F-015
77:03F-016
Irrigation Water
77:02G-115
77:02G-135
77:021-008
77:021-016
77:02K-001
77:03C-001
77:03F-008
77:03F-030
77:03F-057
77 :03F-062
77:03F-071
77.-03F-073
77:03F-074
77:04A-004
77:04A-006
77:04A-009
77:04A-011
77:04A-020
77:04A-040
77:05B-003
77:058-011
77:05B-037
77:05B-040
77:058-041
77:058-042
77:050002
77:05G-020
77:05G-028
77:060-002
77:06E-010
77:06E-012
Irrigation Wells
77:02K-001
77:08C-001
Isotopes
Kansas
Karst
77.-02G-113
77:02G-165
77:05C-005
77:020-005
77:02G-129
77:02K-002
Karst Hydrology
77:02K-002
Kinetics
77:02G-062
77:02G-078
77:02G-148
Laboratory Equipment
77:02G-008
77:021-009
77:07B-004
Laboratory Studies
77:026-154
77:078-031
Laboratory Tests
77:020-003
77:020-004
77:02D-009
77:02E-005
77:02G-001
77:02G-002
77:02G-004
77:02G-006
77:02G-010
77:02G-012
77:02G-013
77:02G-015
77:02G-016
77:02G-022
77:02G-023
77:02G-024
77:02G-030
77:02G-033
77:02G-048
77:02G-056
77:02G-058
77:02G-077
77:02G-081
77:026-083
77:02G-099
77:026-112
77:026-126
77:026-173
77:021-009
77:02J-001
Islands
77:02F-020
303
-------
Laboratory Tests
(cont.)
77:02J-003
77:02J-044
77:02K-002
77:04A-023
77:04A-025
77:04D-004
77:05A-003
77:05B-001
77:05B-018
77:056-053
77-.05B-056
77:050-004
77:050-005
77:05G-036
77:07B-001
77:07B-004
77:078-012
77 :07B-013
77:076-018
77:07B-030
77:078-034
77:078-035
77:088-002
77:088-003
77:088-011
77:08B-016
Lagoons
77:02G-100
77:050-008
Lake Erie
77:058-049
Lake Sediments
77:02J-013
Lakes
Land
77:02J-013
77:058-027
77:058-049
77:050-032
77:05G-034
77:03F-017
77:06E-014
Land Classification
77:03F-017
77:03F-053
77:06E-014
Land Development
77:03F-017
77-.03F-026
77 :03F-053
77:06E-014
Land Management
77:02J-008
77:02J-042
77:03F-053
77:04D-005
77:056-017
77:06E-014
Land Reclamation
77:03F-033
77:050-008
Land Resources
77:02J-008
77:03F-017
77:03F-048
77:03F-053
77:06E-014
Land Subsidence
77:02F-013
Land Use
77:02J-008
77:03F-017
77:03F-026
77:03F-053
77:03F-132
77:056-025
77:058-027
77:058-031
77:06E-014
Laplaces Equation
77:086-008
Latitudinal Studies
77:03F-038
Law Enforcement
77:02F-042
Laws
77:02G-122
Leachate
77:028-001
77:02G-001
77:05B-013
77:058-017
77:058-045
77:056-056
Leaching
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02G-001
:02G-010
:02G-015
:02G-018
:02G-036
:02G-038
:02G-041
:02G-042
:02G-057
:02G-062
:02G-064
:02G-077
:02G-078
:02G-096
:02G-101
:02G-103
:02G-154
:02I-008
:03F-004
:03F-008
:03F-033
:03F-045
:04A-002
:04A-030
Lead
Leakage
Leases
77:048-009
77 :04B-013
77:05B-001
77:058-002
77:058-003
77:058-004
77:058-006
77:058-014
77:056-024
77:058-025
77:058-032
77:058-036
77:056-038
77:056-039
77:056-042
77:058-045
77:05B-048
77:058-056
77:05C-001
77:05G-001
77:05G-004
77:05G-016
77:05G-026
77:068-001
77:078-003
77:078-015
77:078-020
77:078-031
77:02G-067
77:021-013
77:021-019
77:05A-006
77:05B-054
77:050-005
77:02F-025
77 :02F-029
77:02F-037
77:06C-002
Least Squares Method
77:02F-010
Leaves
77:020-002
77 :02D-009
77:021-009
77:021-010
77:03F-034
77:03F-035
77:03F-112
Legal Aspects
77:02F-035
77:05G-003
77:06E-006
77:06E-008
Legislation
Legumes
77 :02F-035
77:06E-006
77:06E-008
77:076-003
304
-------
Limestones
77:02F-030
77:02F-040
77:02F-049
77:02K-002
Limnology
77:05B-054
77:050-003
77:05G-034
Linear Programming
77:03F-018
77 :04B-001
77:04B-006
77:04B-008
77:04B-012
Linings
77:050-037
Liquid Wastes
77:02G-143
Littoral
77:07B-002
Loads (Forces)
77:02G-176
Loam
Loess
77:020-004
77:02G-010
77:026-011
77:02G-022
77:02G-081
77:02G-082
77:02J-044
77:02J-043
77:040-001
Long-Term Planning
77:046-001
Louisiana
Low Flow
77:02G-109
77:04B-005
77:05A-001
Low-Flow Augmentation
77:04A-022
Lysimeters
77:020-003
77:02G-001
77:02G-010
77:02G-036
77:02G-057
77:02G-060
77:02G-065
77:03F-054
77:03F-056
77:03F-064
77:04A-039
77:05B-002
77:058-003
77 :05B-014
77:058-039
77:056-019
77:05G-027
77:076-003
Magnesium
Maize
77:02F-016
77:02G-066
77:02G-107
77:03F-032
77.-04B-009
77:05B-049
77:058-032
Management
77:04A-001
77:04A-040
77:04A-042
77:04B-003
77:04B-006
77:04B-012
77:050-003
77:05G-001
77:06B-002
Manganese
77:03F-032
77:05A-006
Mannings Equation
77:02E-005
Manure
77.-04B-009
Marine Biology
77:058-009
Maryland
77:058-031
Mass Transfer
77:02G-012
77:02G-013
Materials
77:02G-016
Materials Engineering
77:02G-016
Materials Testing
77:02G-016
Mathematical Analysis
77:02J-019
Mathematical Models
77:02B-002
77:020-001
77:020-001
77:020-004
77:020-009
77:020-011
77:02F-003
77:02F-004
77:02F-006
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77.-02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02G-
77:02G-
77:026-
77:026-
77:026-
77:026-
77:02G-
77:02G-
77:02G-
77:02G-
77:02G-
77:02G-
77:02G-
77:026-
77:02G-
77:02G-
77:02G-
77:02G-
77:02G-
77:02G-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:02J-
77:02J-
77:02J-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:04A-
77:04B-
77:04B-
77:04B-
77:04B-
007
008
009
Oil
012
013
014
015
018
019
020
023
025
026
028
031
032
033
034
045
046
047
048
049
002
003
005
010
Oil
012
013
014
015
017
019
021
022
026
027
028
033
035
048
050
056
058
060
074
077
080
124
125
126
127
128
142
143
175
013
041
042
001
003
005
018
136
023
001
-002
-003
004
305
-------
Mathematical Models
(cont.)
77:04B-006
77:04B-008
77:04B-012
77:040-004
77:040-007
77:056-001
77:056-004
77:05B-008
77:05B-016
77:05B-021
77:05B-022
77:058-026
77:05B-027
77:056-047
77:050-003
77:05G-018
77:06A-006
77:08B-008
77:08B-009
Mathematical Simulation
77:05G-007
Mathematical Studies
77:02F-002
77:02F-012
77:02F-017
77:02F-024
77:02F-039
77:02F-050
77:02G-020
77:02G-029
77:02G-047
77:02G-051
77:02G-062
77:02G-079
77:02J-015
77:03F-072
77:046-007
77:046-010
77:05B-008
77:05G-009
Mathematics
77:02F-002
77:02G-019
77:02G-128
77:04B-010
77:056-008
Measurement
77:020-003
77:02F-036
77:02G-034
77:02J-011
77:03F-089
77:04A-011
77:040-005
77:05A-003
77:05A-010
77:07B-030
77:088-007
77:088-011
77:088-016
Mesquite
77:020-007
Meteorological Data
77:020-001
77:020-005
77:020-008
Methodology
77:02F-003
77:02G-047
77:02J-015
77:03F-001
77:03F-005
77:048-003
77:04B-004
77:048-012
77:078-002
Mist
Mixing
Methods
Mexico
77:05A-010
77:03F-005
77:056-044
77:06E-003
Michigan
77:02E-003
Micro Environment
77:03F-035
Micro Organisms
77:03F-012
Microwaves
77:020-034
Mineral Water
77:02F-049
Mineralization
77:02G-114
77:02G-157
77:02G-160
77:02G-161
77:02G-162
77:021-003
77:058-035
Mineralogy
77:05A-006
Mining
77:02G-137
77:02J-036
Minnesota
77:02J-008
77:02J-010
77:068-002
Miscible Displacement
77:02G-175
77:020-010
77:056-050
Missouri
Mercury
77:02G-090
77:05A-006
77:02J-043
77:05G-031
77:05G-032
Model Studies
77:028-001
77 :02B-002
77:02C-001
77:020-003
77:020-004
77:020-005
77:020-009
77:02E-001
77:02E-002
77:02E-003
77:02E-005
77:02E-006
77 :02F-003
77 :02F-007
77:02F-010
77:02F-011
77:02F-012
77:02F-013
77:02F-014
77:02F-018
77:02F-019
77:02F-020
77:02F-022
77:02F-024
77:02F-025
77 :02F-026
77:02F-029
77:02F-031
77-.02F-032
77:02F-033
77:02F-034
77:02F-038
77:02F-039
77:02F-045
77:02F-046
77:02F-049
77:02F-051
77:02G-002
77:020-003
77:02G-005
77:02G-006
77:02G-009
77-.02G-010
77:02G-011
77:02G-014
77:02G-015
77:02G-026
77:02G-027
77:02G-028
77:026-032
77:02G-033
77:026-035
77:02G-036
77:02G-044
77:026-048
77:026-049
77:026-050
77:02G-052
77:02G-056
77:026-058
77 :02G-060
77:026-062
306
-------
Model Studies
(cont.)
77:02G-065
77:02G-070
77:02G-074
77:02G-075
77:02G-080
77:02G-095
77:02G-096
77:02G-101
77:02G-123
77:02G-124
77:02G-125
77:02G-127
77:02G-128
77:02G-129
77:02G-131
77:02G-137
77:02G-138
77:02G-139
77:02G-142
77 :02G-143
77:02G-175
77:021-003
77:021-015
77:02J-004
77:02J-007
77 :02J-011
77:02J-013
77:02J-014
77:02J-015
77:02J-016
77:02J-019
77:02J-020
77:02J-029
77:02J-038
77:02J-039
77:02J-045
77:02K-003
77:03C-002
77:03F-008
77:03F-013
77:03F-038
77:03F-040
77:03F-043
77:03F-060
77:03F-072
77:03F-086
77:03F-088
77:03F-096
77:03F-129
77:03F-132
77:03F-136
77:04A-007
77:04A-009
77:04A-017
77:04A-018
77:04A-019
77:04A-023
77:040-003
77:040-004
77:040-006
77:040-007
77:05A-009
77:058-001
77:05B-004
77:05B-008
77:05B-013
77:05B-016
77:058-021
77:058-
77:05B
77:05B
77:058
77:05B
77:05B
77:05B
77:05B
77:050
77:05G
77:05G
77:05G
77:05G
77:05G
77:05G
77:056
77:05G>
77:05G
77:05G
77:056
77:056
77:06A
77:06A
77:07B
77:078'
77:078
77:08B
022
027
029
038
040
-047
-052
054
008
001
006
007
008
009
019
022
027
029
031
036
039
002
006
009
010
.-027
-009
Molybdenum
77:02G-112
Moisture Content
77:02C-001
77:02G-010
77:02G-011
77:02G-017
77:02G-027
77:02G-033
77:02G-047
77:02G-049
77:02G-060
77:02G-081
77:02G-082
77:02G-127
77:02G-175
77:03C-002
77:04A-023
Moisture Deficit
77:02G-096
77:021-010
77:021-011
77:03F-006
Moisture Stress
77:02G-008
77:021-001
77:021-010
77:021-011
77:02L-001
Moisture Tension
77:020-004
77:02G-008
77:02G-016
Moisture Uptake
77:03F-004
77:03F-006
Mole Drainage
77:02G-071
77:026-092
Monitoring
Montana
77:026-034
77:05A-007
77:056-020
77:058-026
77:058-045
77:056-017
77:078-002
77:03F-043
Monte Carlo Method
77:026-017
Monthly
77:02D-001
Montmorillonite
77:026-004
77:02G-064
77:02G-067
77:026-080
77:02G-121
77:026-130
77:026-131
77:02J-010
Moody Resistance Diagram
77:088-013
Movement
Mulches
Mulching
77 :05B-004
77:058-050
77:02J-023
77:03F-033
77:02G-050
77:03F-020
77:03F-087
77:03F-128
77:058-039
Multiple Purpose
77:050-003
Municipal Wastes
77:05E-002
Municipal Water
77:06E-008
77:06E-011
77:06E-012
Natural Resources
77:02F-044
77:03F-027
Nebraska
77:020-001
77:02D-011
77:02E-004
77:02F-027
77:02F-042
307
-------
Nebraska
(cont.)
77:02F-044
77:020-096
77:03F-020
77:03F-084
77:03F-117
77:04B-015
77:078-035
Nematocides
77:03F-080
Networks
Nevada
77:03F-005
77:04B-003
77:058-037
New Jersey
77:06E-008
New Mexico
Nitrates
77:02F-040
77:02F-049
77:03F-106
77:03F-107
77:058-005
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02G-036
:02G-037
:02G-038
:02G-040
:02G-063
:02G-096
:02G-097
:02G-103
:02G-105
:02G-113
:02G-120
:02G-147
:02G-165
:02I-012
:02K-005
:03F-049
:03F-057
:04B-013
:05A-002
:05A-004
:05A-007
:05A-009
:05B-004
:05B-005
-.058-010
:05B-011
:05B-016
:05B-017
:05B-020
:05B-024
:05B-025
:05B-031
:05B-039
:05B-042
:05B-048
:05B-050
:05B-053
:05B-055
:05D-007
77:050-009
77:05G-004
77:05G-026
77:07B-015
77:078-020
77:07B-035
Nitrification
77:02G-036
77:02G-053
77:026-062
77:02G-103
77:02G-160
77:02G-169
77:021-003
77:02K-005
77:05A-010
77:05B-036
77:05B-051
77:05D-002
77:050-005
77:05E-002
77:07B-032
Nitrites
77:020-097
77:02G-113
77:02G-159
77:026-163
77:058-025
77:058-048
77:07B-034
Nitrogen
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02B-001
:02G-040
:020-041
:026-053
:02G-063
:02G-096
:02G-099
:02G-100
:02G-103
:02G-104
:02G-113
:02G-114
:02G-120
:02G-143
:02G-146
:02G-147
:026-159
:020-160
:026-161
:02G-162
:02G-163
:02G-165
:02G-169
:020-170
:02G-171
:02I-003
:02I-012
:02J-008
:02J-011
:02J-044
:02J-046
:02K-005
:03F-004
:03F-014
:03F-032
:03F-043
77:03F-045
77:03F-049
77:03F-056
77:03F-090
77:03F-108
77:03F-109
77:03F-127
77:03F-131
77:05A-002
77:05A-010
77:058-014
77:05B-026
77:058-029
77:058-030
77:05B-031
77:05B-033
77:056-035
77:058-036
77:058-038
77:05B-039
77:05B-043
77:058-048
77:058-050
77:05B-053
77:058-055
77:050005
77:05D-008
77:05G-004
77:056-005
77:056-019
77:050-031
77:078-003
77:07B-010
77:078-014
77:078-016
77:078-020
77:078-032
77:07B-033
Nitrogen Compounds
77:048-015
77:05A-010
77:058-048
77:050-004
Nonhomogeneous Soils
77:020-125
Nonpoint Source Pollution
77:05G:023
77:05G-040
North Dakota
77:026-005
77:021-018
77:03F-058
Nuclear Meters
77:02G-047
Nuclear Moisture Meters
77:02D-003
77:020-047
Nuclear Powerplants
77:058-022
Nuclear Reactors
77:058-007
308
-------
Nuclear Wastes
77:05B-007
Numerical Analysis
77:02F-001
77:02F-009
77:02F-010
77:02F-012
77:02F-014
77:02F-028
77:02F-029
77:02G-027
77:02G-077
77:02J-015
Nutrient Removal
77:026-143
Nutrient Requirements
77:03F-004
Nutrients
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
7-7:
77:
77:
77:
77:
77:
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
02E
02G
02G
026
:026
:02G
:02G
:02G
:026
:02G
:02G
:02G
:02G-
:026-
:02G-
:02I-
:02J-
:02J-
:02J-
:02J-
:03F-
:03F'
:03F-
:03F-
:03F'
:03F
:03F
:03F
:03F
:03F
03F
03F
03F
03F
03F
03F
03F
03F-
04A-
04A-
05B-
05B-
05B-
05B
05B-
058-
058-
058-
-003
i-053
-057
r-062
,-101
i-104
;-i34
,-143
,-147
,-149
1-150
i-157
163
170
012
008
010
044
046
013
014
-022
032
033
045
-047
-049
-062
090
-102
-108
-109
-116
-127
-129
-130
132
-006
-042
-Oil
014
026
029
030
032
046
048
77:05B-055
77:050-007
77:05G-004
77:05G-015
77:05G-019
77:05G-023
77:056-027
77:05G-031
77:056-033
77:056-040
77:078-002
77:07B-014
77-.07B-015
77:07B-018
Oak Trees
77:058-022
77:058-045
77:058-050
77:088-007
On-Site Tests
77:02D-002
77:020-003
77:020-005
77:026-125
77:02J-011
77.-02J-041
77:040-005
77:05B-050
77:078-001
77:02G-014
Onions
Oats
77:021-010
77:021-011
77:02J-023
77:040-005
Observation Wells
77:02F-037
77:026-025
77:048-007
77:058-019
77:03F-042
77:03F-079
Ohio
77:028-001
77:046-012
77:040-005
77:058-049
Oklahoma
77:02G-114
On-Site Data Collections
77:03F-089
77:05B-017
77:058-031
On-Site Investigations
77:02E-004
77:02F-036
77:026-003
77:026-005
77:026-006
77:026-007
77:026-014
77:026-015
77:026-017
77:026-018
77:02G-031
77:026-050
77:02G-060
77:026-082
77:026-174
77:021-011
77:02J-011
77:02K-001
77:040-001
77:040-005
77:058-002
77:058-003
77:058-005
77:058-018
Open Channel Flow
77:02E-001
77:078-025
77:078-026
77:078-027
77:078-029
77:088-001
77:088-003
Open Channels
77:02J-007
77:040-007
77:05A-001
77:078-026
77:088-001
Operations
77 :03F-003
77:03F-021
Operations Research
77:048-004
77:056-003
Optimization
77:02F-039
77:026-019
77:03C-002
77:03F-001
77:03F-003
77:03F-088
77:04A-001
77:048-001
77:048-003
77:048-004
77:048-006
77:048-008
77:050-003
77 :05G-003
77:05G-018
77:08B-004
Orchards
77:02G-049
77:03F-086
77:03F-121
77-.04A-008
77 :04A-026
309
-------
Oregon
77:02G-082
77:06E-013
Organic Compounds
77:020-156
Organic Loadings
77:05B-026
Organic Material
77:02F-030
Organic Matter
77:02G-082
77:02G-089
77:02G-090
77:02G-119
77:02G-157
77:026-172
77:03F-012
77:03F-030
77:03F-128
77:050-002
Orifice Flow
77:03F-089
Orifices
77:03F-089
77:04A-028
77:08B-005
77:086-008
Osmotic Pressure
77:02G-008
Overflow
77:08B-011
Path of Pollutants
77:02G-015
77:02G-018
77:026-022
77:02G-143
77:05B-001
77:05B-002
77:058-004
77:05B-008
77:05B-009
77:058-021
77:058-024
77:056-025
77:058-027
77:056-056
77:056-032
Permits
77:05G-021
Peaches
77:020-010
77:03F-086
Peak Discharge
77:040-006
Peanuts
77:03F-039
77:03F-044
Overland Flow
77:02E-005
77:026-142
77:02J-042
77:02J-044
Oxidation
77:02G-085
77:02G-158
77:02G-159
77:058-051
Oxidation-Reduction Potential
77:05A-006
Particle Size
77:02F-005
77:02G-016
77:056-049
77:058-051
Pasture Management
77:03F-015
77:03F-016
Pennsylvania
77:02K-002
77:05B-050
Perched Water
77:026-025
Percolation
77:026-002
77:02F-001
77:026-003
77:026-078
77:026-096
77:026-142
77:05B-004
77:05B-010
77:05B-050
77:05G-004
Perlite
77:026-008
Pastures
77:026-071
77:03F-015
77:03F-016
77:05A-003
Permability
77:028-002
77:02F-005
77:02F-006
77:02F-007
77:02F-009
77:02F-014
77:02F-015
77:02F-019
77:02F-020
77:02F-033
77:02F-034
77:02F-036
77:02F-047
77:02F-049
77:026-004
77:026-030
77:026-095
77:026-142
77:026-174
Permselective Membranes
77:05A-009
Pesticide Removal
77:056-002
Pesticide Residues
77 :05B-006
Pesticides
77:02E-003
77:02G-175
77:03F-116
77:04A-042
77:056-006
77:058-009
77:058-011
77:058-041
77:05B-046
77:058-056
77:05G-002
77:056-011
77:056-023
77:056-024
77:056-040
Petrology
77:02K-002
Phosphates
77:026-059
77:026-084
77:026-132
77:026-135
77:026-164
77:03F-057
77:04A-006
77:05A-003
77:05A-004
77:05B-001
77:056-011
77:058-025
77:05D-004
77:050-006
77:050-009
Phosphorus
77:026-001
77:02G-052
77:026-059
77:026-099
77:02G-109
77:026-110
77:026-143
77:026-149
77:026-150
77:026-151
77:02J-008
77:02J-011
77:02J-044
77:02J-046
77:03F-004
77 :03F-022
77:03F-031
77 :04B-014
77:05A-003
310
-------
Porous Media
77:020001
77:02F-002
77:02F-007
77:02F-009
77:02F-012
77:02F-014
77:02F-024
77:02F-033
77:02F-034
77:02F-052
77:02G-002
77:02G-012
77:02G-013
77:02G-016
77:026-018
77:020-030
77:02G-033
77:02G-061
77:02G-094
77:02G-124
77:02G-127
77:026-143
77:02G-004
77:02G-011
77:026-035
77:088-003
Pressure Head
77:026-033
77:026-035
77:026-058
77:02G-126
77:026-175
77:02G-176
Prices
Pricing
77:03F-001
77:03F-073
77:03F-074
77:03F-135
77:056-003
Priorities
77:06B-002
77:03F-107
77:03F-113
77:04A-001
77 :04A-041
77:04B-001
77:04B-004
77:04B-005
77:04B-006
77:04B-007
77:04B-012
77:046-015
77:05B-020
77:056-017
Pumping Plants
77:02F-051
77:03F-070
77:03F-107
77:04A-041
77:08C-001
Pumping Recharge
77:046-003
Potassium
Potatoes
77:02B-001
77:026-066
77:026-145
77:026-148
77:02J-008
77:03F-032
77:04B-009
77:05B-011
77:05B-049
77:03F-045
77:03F-056
77:05B-017
77:056-005
Potentiometric Level
77:02F-006
Powerplants
77:04A-041
77:05B-022
Precipitation (atmospheric)
77:028-002
77:02E-004
77:02F-011
77:026-032
77:026-034
77:026-050
77:026-060
77:02G-127
77:026-142
77:02J-044
77:058-021
Precipitation Excess
77:028-002
Precipitation Intensity
77:02B-002
Probability
77:048-004
Profiles
77:020-003
77:026-010
77:026-027
77:026-033
77:088-003
Project Feasibility
77:03F-001
Project Planning
77:03F-001
Projects
77:06C-001
Properties
77:02G-078
Public Benefits
77:068-001
Public Health
77:058-031
Public Rights
77:06A-005
Pump Testing
77:02F-036
77:02F-051
Pumping
Pressure
77:020-008
77:026-002
77:02F-013
77:02F-019
77:02F-023
77:02F-025
77:02F-028
77:02F-037
77:02F-047
77:02F-048
77:03F-021
77:03F-106
Pumps
Radiation
77:02F-051
77:03F-106
77:03F-107
77:080-001
77:020-008
Radioactive Wastes
77:058-007
Radiochemical Analysis
77:058-007
Radioisotopes
77:020-054
77:058-007
Raindrops
Rainfall
77:02G-079
77:02J-001
77:028-002
77:020-008
77:02F-023
77:02F-049
77:026-034
77:026-050
77:026-058
77:026-060
77:020-071
77:026-075
77:020-096
77:026-127
77:026-137
77:026-142
77:02J-001
77:02J-008
77:02J-015
77:02J-023
77:02J-025
77:02J-042
77:02J-044
312
-------
Rainfall
(cont.}
77:03F-003
77:03F-109
77:040-005
77:05B-033
77:05B-052
77:078-011
Rainfall Intensity
77:026-001
77:02G-050
77:026-075
Rainfall Patterns
77:02B-002
Rain-Runoff Relationships
77:026-032
77:026-075
77:026-095
77:02J-008
Rainfall Simulators
77:02J-001
77:07B-011
Range 6rasses
77:02E-005
Rating Curves
77:088-016
Recharge
77:02F-011
77:02F-025
77:02F-032
77:02F-040
77:02F-049
77:048-012
77:050-004
77:050-005
Recharge Ponds
77:05A-007
Recycling
77:04A-005
77:050-001
Reflectance Analysis
77:020-002
Regional Analysis
77:04A-022
77:048-003
Regions
77:03F-018
77:050-003
77:06C-001
Regression Analysis
77:026-036
77: 02G-056
77:026-173
77:038-001
77:03F-005
77:04B-005
Regulation
77:056-021
Remote Sensing
77:026-034
Research and Development
77:03F-007
Reservoir Design
77:040-006
Reservoir Silting
77:02J-015
Reservoir Storage
77:02J-015
Reservoirs
77:02J-015
77:04A-022
77:048-003
77:056-031
77:056-032
77:056-033
Resistivity
77:02F-005
77:02F-021
77:02F-036
Resource Development
77:03F-077
Resources
77:02F-044
77:03F-077
Respiration
77:026-158
Retention
77:026-032
77:02G-081
Return Flow
77:026-038
77:026-039
77:026-044
77:026-103
77:021-004
77-.02J-010
77:03A-001
77.-03F-007
77:03F-008
77:03F-057
77:04A-004
77:04A-005
77:04A-006
77:04A-008
77-.04A-009
77:04A-010
77:04A-029
77:04A-030
77:04A-042
77:05A-004
77:05A-005
77:056-003
77:058-011
77 -.058-012
77.-05B
77:058
77:058
77:056
77:056
77:056
77:056
77:056
77:056
77:056
77:056'
77:056
77:056-
77:056'
77:06A-
77:06A-
77:06A-
77:06E-
77:06E-
77:06E-
77:078-
-013
-017
-037
-005
008
010
Oil
019
020
022
027
028
030
034
001
003
006
002
004
006
010
Return (Monetary)
77:03F-001
Reviews
77:02J-004
Reynolds Number
77:026-030
Rhodamine
77:076-001
Rhode Island
77:02F-036
Rice
77:026-
77:026-
77:026-
77:021-
77:03F-
77:03F-
77:058-
77:058-
77:050-
008
099
109
019
002
046
006
Oil
004
Rill Erosion
77:02J-041
77:02J-042
Rio Grande River
77:04A-008
Risks
77-.02J-015
77:03F-001
River Basins
77:04A-001
77:04A-022
77:048-012
77:050-003
77:056-003
77:05G-023
Rivers
77:02E-001
77:02J-043
77:058-002
77:056-001
313
-------
Salinity
(cont.)
77:05G-014
77:05G-015
77:05G-016
77:05G-018
77:05G-019
77:05G-022
77:05G-027
77:05G-037
77:06A-006
77:06E-003
77:076-006
77:090-001
Salt Balance
77:04A-001
Salt Tolerance
77:021-006
77:03C-001
77:058-028
77:05G-035
Salts
Sampling
77:02D-004
77:02G-004
77:02G-015
77:02G-078
77:02G-083
77:020-155
77:02G-160
77:02G-175
77:026-176
77:021-006
77:021-008
77:030001
77:03F-116
77:04A-026
77:04A-029
77:04A-030
77:05A-005
77:05A-007
77:05A-008
77:05B-015
77:05B-021
77:058-028
77.-05B-039
77:056-034
77:056-037
77:026-001
77:026-003
77:026-017
77:026-038
77:026-040
77:026-054
77:026-068
77:02G-158
77:021-017
77:021-018
77:02J-002
77:02J-011
77:03F-010
77:03F-011
77:03F-059
77:05A-007
77:058-017
77:058-020
77:05B-
77:058-
77:058-
77:05B
77:056
77:07B
77:07B
77:07B
77:078
77:07B
77:07B
77:078
77:07B
77:078
77:07B
77:07B
77:07B
77:078
77:078
77:08A
77:088
031
034
050
055
'033
005
008
012
013
018
019
020
021
023
031
032
033
035
036
001
004
Scheduling
Sand Aquifers
77:02F-005
Sands
77:026-022
77:026-027
77:026-096
77:026-167
77:02J-002
77:03F-056
77:058-001
77:05B-010
77:050-004
Sandstones
77:02F-005
77:02F-021
77:02F-025
Satellites (Artificial)
77:026-034
77:02L-001
Saturated Flow
77:02F-004
77:02F-014
77:026-016
77:026-022
77:026-023
77:026-094
77:026-128
77:04A-025
77:088-008
Saturated Soils
77:026-113
77:026-127
77:021-019
77:03F-046
77:050-004
Saturation
77:026-058
77:021-018
Scour
Screens
Sea Water
Seasonal
77:03F-050
77:03F-082
77:03F-117
77:078-036
77:02J-043
77:02F-019
77:02F-028
77.-04B-011
Scaling
77:026-031
77:038-001
77:048-004
77:05B-020
Sediment Control
77:02J-012
77:02J-019
77:02J-035
77:02J-036
77:02J-039
77:04A-042
77:04D-007
77:06A-001
77:08B-005
Sediment Discharge
77:02J-012
77:02J-013
77:02J-015
77:02J-029
77:02J-030
77:02J-037
Sediment Load
77:02J-011
77:02J-012
77:02J-018
77:02J-019
77:02J-025
77:02J-026
77:02J-029
77:02J-030
77:02J-039
77:03F-063
77:04A-035
77:040-004
Sediment Transport
77:02J-001
77:02J-002
77:02J-004
77:02J-011
77:02J-012
77:02J-013
77:02J-016
77:02J-025
77 :02,T-0?8
77:02J-029
77:02J-031
77:02J-032
77:02J-034
77:02J-039
77:02J-040
77:02J-042
315
-------
Sedinent Transport
(cont.)
77:040-004
77:040-007
77:058-049
Sediment Yield
77:02J-004
77 :02J-015
77:02J-017
77:02J-041
77:02J-042
77:04A-006
77-.04D-005
77:04D-006
Sediment-Water Interfaces
77:021-018
Sedimentary Basins
77:02J-018
Sedimentary Rocks
77:02K-002
Sedimentation
77:
77;
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
02J-002
02J-003
02J-004
02J-007
02J-011
02J-012
02J-013
02J-018
02J-019
02J-024
02J-028
02J-030
02J-045
04A-042
04D-001
04D-004
05B-033
05B-046
05B-053
05B-054
05C-003
05G-022
05G-024
05G-031
06E-007
07B-011
08B-005
Sediments
77:02E-003
77:02G-071
77:02G-149
77:021-018
77:021-019
77:02J-002
77:02J-003
77:02J-010
77:02J-011
77:02J-012
77:02J-014
77:02J-017
77:02J-018
77:02J-024
77:02J-025
77:02J-026
77:02J-027
77:02J-029
77:02J-030
77:02J-035
77:02J-036
77:02J-037
77:02J-038
77:02J-039
77:02J-044
77:02J-045
77:03F-062
77:03F-063
77:03F-116
77:04A-006
77:04A-042
77:040-004
77:040-007
77:05A-004
77:05B-007
77:05B-009
77:058-030
77:05B-033
77:05B-048
77:05B-049
77:05B-053
77:05B-054
77:05C-003
77:05G-002
77:05G-025
77:05G-031
77:05G-032
77:056-033
77 :07B-002
77:078-011
Sedimentology
77:02J-002
77:02J-013
Seed Treatment
77:030001
Seeds
Seepage
77:03C-001
77:03F-085
77:02F-001
77:02F-009
77:02F-015
77:02F-052
77:026-003
77:02G-021
77:02G-048
77:02G-054
77:02G-124
77:02G-143
77:021-008
77:03F-063
77 :03F-095
77:04A-015
77:05A-005
77 :05G-007
77:05G-036
77:07B-024
77:09C-001
Seepage Control
77:02G-124
77:05G-036
Semiarid Climates
77 :03C-001
77:060-002
Settling Basins
77:08B-005
Settling Velocity
77:08B-005
Sewage Disposal
77:05G-017
Sewage Sludge
77 :05B-045
Sewage Treatment
77:050-008
77:05E-002
Shallow Wells
77:056-020
Shape
77:02F-008
Shear Strength
77:02G-079
Shear Stress
77:02J-003
77:02J-042
77 :08B-001
Sheet Erosion
77:026-007
77:02J-001
77-.02J-041
77:02J-042
Silts
77:02G-082
77:02J-003
77:02J-010
77:02J-044
Silviculture
77:026-153
Simulated Analysis
77:02E-002
77:02E-051
77:026-010
77:026-027
77:02G-044
77:026-052
77:026-076
77:026-094
77:026-123
77:02G-137
77:021-003
77:021-015
77:02J-007
77:02J-016
77:02J-017
77:02J-019
77 :02J-031
316
-------
Simulated Analysis
(cont.)
77:03F-003
77:03F-072
77:03F-088
77:03F-096
77:03F-129
77:04A-001
77:04A-007
77:04A-017
77:04A-019
77:04B-002
77:046-008
77:048-012
77:056-013
77:058-029
77:05B-040
77:05B-052
77:05G-006
77:050-008
77:050-009
77:05G-019
77:05G-028
77:05G-029
77:05G-031
77:078-009
77:078-010
77:078-011
77:088-009
Simulated Rainfall
77:028-001
77:02G-058
77:02J-001
77: 02J-044
Sinks
77:02F-010
Slope Stability
77:040-001
Slopes
Sludge
77:028-001
77:02F-008
77:02J-001
77:02J-041
77:02J-043
77:05E-002
Sludge Disposal
77:058-045
Sluice Gates
77:088-003
Sluices
77:088-003
Small Watersheds
77:02E-005
Snowmelt
77:02J-008
Social Aspects
77:02J-027
Social Needs
77:068-001
Social Participation
77:068-001
Social Values
77:02J-027
Sodium
77:02F-016
77:026-066
77:026-080
77:02G-081
77:02G-107
77:02G-108
77:02G-121
77:02J-008
77:048-009
77:058-005
77:058-049
77:05G-037
Sodium Chloride
77:02G-004
77:03C-001
77:058-019
Soil Aggregates
77:026-012
77:026-013
Soil Amendments
77:026-046
77:02G-154
77:02G-160
77:026-161
77:02G-162
77:026-168
77:058-045
77:05E-002
Soil Analysis
77:026-047
77:030002
77:058-006
77:056-009
77:058-048
77:058-049
Soil Chemical Properties
77:026-015
77:02G-067
77:026-069
77:026-078
77:02G-098
77:02G-106
77:026-110
77:026-111
77:026-112
77:026-164
77:02G-165
77:026-169
77:03F-015
77:03F-016
77:056-001
Soil Chemistry
77:026-069
77:026-084
77:026-085
77:026-089
77:026-090
77:026-098
77:026-101
77:026-102
77:026-105
77:026-106
77:026-107
77:026-110
77:026-111
77:026-112
77:026-121
77:026-130
77:026-131
77:02G-132
77:026-133
77:026-134
77:02G-135
77:026-145
77:026-146
77:026-148
77:026-150
77:026-151
77:026-155
77:026-157
77:026-158
77:02G-161
77:026-162
77:026-163
77:026-164
77:02G-165
77:026-169
77:026-170
77:02K-001
77:02K-003
77:03F-015
77:03F-016
77:03F-132
77:056-001
77:058-023
77:058-049
77:056-004
77:05G-029
77:06A-006
Soil Compaction
77:026-136
77:03F-110
Soil Conservation
77:02J-034
77:03F-020
77:03F-051
77:03F-052
77 :03F-066
77:04A-042
77:058-030
Soil Contamination
77:026-001
77:058-006
77:056-008
77:056-009
77:056-024
77:058-045
77:058-056
317
-------
Soil Density
77:026-161
77:020-162
77:03F-110
Soil Environment
77:02J-008
77:03F-099
77:07B-008
Soil Erosion
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77:
77;
77:
77:
77;
77;
77:
77:
77:
77:
77;
77:
77:
77:
02B-
026-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
02J-
:02J-
02J-
:02J-
;02J-
:02J-
;02J-
:02J-
:02J-
:02J-
:02J-
:03F-
:03F-
:03F-
:03F-
:05B-
:05G-
:06E-
:07B-
001
173
001
008
010
012
016
017
020
022
023
025
027
028
029
030
031
032
033
034
035
037
038
040
-041
042
044
046
-048
-051
052
-110
-030
025
-007
-Oil
Soil Filters
77:050-004
77:050-005
Soil Gases
77:07B-016
Soil Horizons
77:02G-032
Soil Investigations
77:02G-005
77:02G-036
77:02G-038
77:02G-039
77:02G-041
77:026-043
77:02G-051
77:026-052
77:026-057
77:026-059
77:026-062
77:026-
77:026-
77:026-
77:026-
77:02G-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:02G-
77:02G-
77:02G-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:02G-
77:02G-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:026-
77:02G-
77:026-
77:026-
77:026-
77:026-
77:02G-
77:026-
77:02G-
77:02G-
77:026-
77:026-
77:02G-
77:02G-
77:02G-
77:02J-
77:02J-
77:02K-
77:03F-
77:03F-
77:03F-
77:03F'
77:03F-
77:03F'
77:03F
77:03F'
77:03F'
77:03F
77:04A
77:04B
77:05B
77:05B-
063
066
068
069
070
071
076
084
085
089
090
097
098
099
100
102
105
106
107
108
109
110
111
112
113
114
119
120
121
133
144
145
146
147
148
149
151
152
155
157
158
159
161
162
164
165
166
167
168
169
170
171
172
008
024
003
012
-013
-015
016
031
-041
-099
-111
-127
-128
-029
-014
-015
032
77:05B-039
77 :05B-043
77:058-052
77:05C-004
77:07B-006
77:07B-008
77:078-012
77:078-016
77:078-017
77:078-019
77:07B-037
Soil Management
77:02J-008
77:03F-048
77:03F-051
77:03F-052
77:03F-110
77:05B-003
77:05B-041
Soil Mechanics
77:04D-001
Soil Microorganisms
77:026-166
Soil Moisture
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02D-004
:02D-011
:02F-031
:02G-003
:026-005
:02G-006
:026-008
:026-009
:026-010
: 026-030
:02G-033
:02G-034
:02G-035
:02G-039
:02G-047
:02G-054
:02G-055
:02G-071
:02G-074
:026-078
:02G-087
:026-088
:026-091
:02G-114
:02G-115
:02G-129
:026-136
:02G-142
:02G-146
:02G-148
:02G-151
:02G-152
:02G-155
:02G-156
:026-170
:02I-002
:02I-005
:02I-007
:02I-008
:02I-014
-.021-015
:02I-016
318
-------
Soil Moisture
(cont.}
77:030002
77:03F-003
77:03F-020
77:03F-023
77:03F-028
77:03F-036
77:03F-042
77:03F-044
77:03F-046
77:03F-050
77:03F-054
77-.03F-069
77:03F-075
77:03F-078
77:03F-082
77:03F-090
77:03F-094
77:03F-099
77:03F-109
77:03F-112
77:03F-126
77:03F-136
77:04A-026
77:04A-029
77:04D-006
77:05B-035
77:05B-041
77:06D-002
77:07B-006
77-.07B-023
77-.07B-036
77-.07C-002
Soil Moisture Meters
77:02G-034
77:02G-047
Soil Particles
77:03F-095
Soil Physical Properties
77:02G-031
77:02G-040
77:02G-046
77:026-074
77:020-125
77:02G-168
77:02G-174
77:02G-176
77:03F-099
77:03F-110
77:04A-036
Soil Physics
77:020-004
77:02G-002
77:02G-003
77:02G-006
77:02G-031
77:02G-035
77:02G-074
77:026-127
77:026-173
77:02G-174
77:02G-175
77:03F-132
77:04A-023
77:05B-002
77:05B-024
Soil Profiles
77:020-004
77:020-005
77:02G-032
77:02G-051
77:02G-120
77:02G-129
77:026-154
77:02G-167
77:03F-015
77:03F-016
77:03F-111
77:05B-002
77:05B-003
77:05B-004
77:05B-055
77:050-004
77:056-040
77:078-016
77:07B-019
77:07B-020
Soil Properties
77:028-002
77:02D-009
77:02G-005
77:02G-010
77:02G-015
77:02G-017
77:020-028
77:026-032
77:02G-046
77:026-047
77:026-050
77:026-055
77:026-056
77:026-060
77:02G-067
77:026-069
77:026-080
77:026-081
77:026-082
77:026-083
77:026-089
77:02G-091
77:02G-096
77:026-099
77:02G-104
77:02G-107
77:026-108
77:02G-109
77:026-119
77:02G-121
77:026-130
77:026-131
77:026-132
77:02G-133
77:02G-134
77:026-140
77:026-143
77:020-148
77:020-150
77:02G-157
77:026-158
77:026-168
77:02G-169
77:02G-172
77:026-173
77:026-174
77:02K-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:03F-
77:04A-
77:04B-
77:05B-
77:058-
77:058-
77:078-
77:07B-
77:07B-
77:078-
77:07B-
77:078-
005
043
048
080
099
100
103
110
036
014
015
041
042
008
012
016
019
023
037
Soil Science
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
77
:02D-004
:02F-033
:026-001
:026-002
:026-003
:02G-004
:02G-005
:02G-006
:02G-015
: 026-016
:026-017
:026-018
:02G-022
:026-023
:026-024
:02G-027
:02G-035
:02G-056
:02G-058
:02G-074
:02G-080
=026-083
:02G-127
:02G-174
:02G-175
:02J-001
:02J-008
:04A-023
:05B-002
:05B-056
Soil Solutions
77:026-083
Soil Strength
77:026-079
77:040-001
Soil Structure
77:026-023
77:020-024
77:03F-110
77:03F-111
Soil Surface
77:03F-048
519
-------
Soil Temperature
77:02G-005
77:02G-006
77:02G-007
77:02G-051
77:02G-104
77:02G-140
77-.03F-041
77:03F-055
Soil Tests
77 :02G-047
77:02G-068
77:02G-089
77:02G-097
77:02G-107
77:02G-126
77:02G-158
77:03F-111
77:078-008
77:078-019
77:07B-020
77:076-037
Soil Texture
77:02G-104
77:02G-110
77:02G-119
77:02G-161
77:02G-162
77:02G-167
77:02G-171
77:02J-024
77:02J-043
77:04A-036
77:078-006
77:078-012
Soil Treatment
77:02G-046
77:03F-111
Soil Types
77:02G-035
77:026-126
77:03F-111
77:058-010
Soil Water
77:020001
77:02D-003
77:020-004
77:020-005
77:020-009
77:02E-002
77:02F-031
77:02F-032
77:02F-033
77:02G-001
77:02G-002
77:02G-003
77:02G-004
77:026-005
77:026-006
77:02G-007
77:026-010
77:026-014
77:026-016
77:026-017
77:026-018
77:02G-019
77 :02G-020
77:026-022
77:026-028
77:026-030
77:026-032
77:026-033
77:026-034
77:026-035
77:026-041
77:026-043
77:02G-046
77:026-047
77:02G-048
77:02G-054
77:026-055
77:02G-056
77:026-058
77:02G-060
77:026-061
77:02G-074
77:026-078
77:026-081
77:026-082
77:026-087
77:026-088
77:02G-091
77:026-093
77:026-094
77:026-095
77:026-096
77:026-114
77:02G-115
77:026-124
77:026-128
77:026-129
77:026-136
77:026-137
77:026-138
77:026-139
77:026-140
77:026-143
77:026-146
77:026-148
77:026-151
77:026-152
77:02G-156
77:026-168
77:026-174
77:02G-175
77:021-002
77:021-003
77:021-005
77:021-007
77:021-008
77:021-014
77:021-015
77:02K-001
77:03B-001
77:030002
77:03F-004
77:03F-010
77:03F-011
77:03F-020
77:03F-034
77:03F-035
77:03F-036
77:03F-042
77 :03F-044
77:03F-046
77:03F-050
77:03F-054
77:03F-067
77:03F-069
77:03F-075
77:03F-078
77:03F-082
77:03F-090
77:03F-099
77:03F-109
77:03F-112
77:03F-132
77:04A-003
77:04A-023
77:04A-025
77:04A-026
77 :04A-029
77:04A-040
77:048-002
77:058-002
77 :05B-035
77:058-041
77: 05B-050
77:050-004
77:056-005
77:078-006
77:078-015
77:07B-023
77:076-036
77:076-002
Soil Water Movement
77:028-002
77:020-003
77:020-004
77:020-009
77:02F-033
77 :026-002
77:026-003
77:026-004
77:026-006
77:02G-009
77:026-010
77:02G-014
77:026-017
77:026-018
77:026-019
77 :026-020
77 :02G-021
77:026-022
77:026-023
77:026-024
77 :02G-025
77:02G-026
77:026-027
77:026-028
77:026-029
77:02G-030
77:026-031
77:026-033
77:026-035
77:026-041
77:026-043
77:026-046
77:02G-048
77:02G-049
77 :02G-054
320
-------
Soil Water Movement 77.n7r mi
/ ,, //:UzG UXX VT-n^r-iTi
(cont-> 77.n?r:_nT7 :;-r:G"H^
77:02G-°56 77:02G-021 7720-135
77:02G-022 77;02G-136
77:02G-023 77:02G-140
77:02G-024 77:02G-141
77:020-076 77:02G-026 77-02G-144
77:02G-078 77:02G-027 77:02G-145
77:026-080 77:02G-028 77:02G-146
77:026-087 77:02G-029 77:026-147
77:02G-093 77:02G-030 77-02G-148
77:02G-094 77:02G-031 77^026-149
77:02G-115 77:02G-034 77-02G-150
77:02G-116 77:02G-035 77-026-151
77:02G-124 77:02G-036 77-02G-152
77:02G-126 77:02G-037 77-02G-154
77:02G-128 77:02G-038 77-02G-155
77:02G-137 77:02G-039 77:02G-158
77:02G-138 77:02G-040 77-02G-159
77:026-139 77:02G-041 77:02G-173
77:026-140 77:02G-043 77:02G-174
77:026-142 77:02G-050 77:02G-176
77:026-143 77:02G-051 77:02J-010
77:02G-152 77:02G-052 77:02J-024
77:026-174 77:02G-053 77:02J-043
77:026-175 77:020-054 77:02J-044
77:021-002 77:026-056 77:02K-003
77:021-003 77:026-057 77:03P-012
77:021-008 77:026-058 77:03F-022
77:03F-010 77:02G-059 77:03F-031
77:03F-011 77:026-060 77:03F-041
77:03F-067 77:026-062 77:03F-080
77:04A-023 77:026-063 77:03F-081
77:04A-025 77:026-066 77:03F-099
77:04A-026 77:026-068 77:03F-100
77:05B-001 77:026-069 77:03F-103
77:05B-002 77:026-070 77:03F-128
77:058-004 77:026-074 77:03F-132
77:05B-024 77:026-076 77:04A-031
77:056-039 77:02G-077 77:04A-036
77:056-050 77:02G-079 77:04B-014
77:078-015 77:02G-080 77:040-005
77:070-002 77:020-081 77:05A-004
77:088-008 77:020-083 77:058-001
77:020-084 77:05B-002
Soil-Water-Plant Relationships 77:026-085 77:05B-015
77:020-009 77:02G-087 77:05B-032
77-02D-011 77:02G-089 77:058-039
77:02G-005 77:02G-090 77:058-042
77:026-008 77:026-091 77:058-043
77-02G-096 77:026-095 77:058-045
77-021-002 77:026-097 77:058-052
77:021-010 77:02G-098 77-.05C-004
77:021-011 77:026-099 77:05D-004
77-02K-005 77:026-100 77:056-026
77-02L-001 77:026-105 77:056-035
77-030001 77:02G-108 77:05G-036
77-03F-004 77:026-109 77:05G-037
77-03F-136 77:02G-110 77:06A-006
77:02G-111 77:078-006
77:02G-112 77:078-008
77:028-001 77:02G-113 "^^nifi
77:028-002 77:026-114 77:073-016
77:020-001 77:02G-119 "-.078-017
77:020-004 77:026-120 ":°^-019
77:02F-033 77:020-121 77:078-037
77:026-002 77:026-123
77:026-003 77:020-125
77:020-010 77:020-130
321
-------
Solar Radiation
77:020-002
77:03F-070
77 :03F-084
77:03F-106
77 :03F-107
77:03F-118
Solid Wastes
77:050-009
Solubility
Solutes
77:02K-002
77:05B-023
77:02G-010
77:02G-018
77:02G-021
77:020-022
77:02G-077
77:02G-124
77:02G-143
77:02G-175
77:056-004
77:05B-016
Solutions
Solvents
Sorghum
Sorption
77:026-004
77:02G-001
77:05B-002
77:02G-104
77:03F-022
77:03F-040
77:02G-012
77:02G-013
77:02G-022
77:02G-029
77:02G-088
77:02G-098
77:026-106
77:04B-014
South Carolina
77:02G-054
77:05B-007
South Dakota
77:02G-125
77:021-016
Soybeans
77:02G-046
77:02G-105
77:021-001
77:03F-047
77:03F-071
77:03F-087
Spatial Distribution
77:02F-049
77:026-017
77:026-018
Specific Conductivity
77:05A-006
77:05A-007
Specifications
77:05A-001
Spectrophotometry
77:02D-002
Stagnant Water
77:02G-077
Spraying
Sprays
77:03B-001
77:05B-006
Spring Water
77-.02F-030
Springs
77:02F-030
Sprinkler Irrigation
77:020-010
77:02F-027
77:026-037
77:026-058
77:026-123
77:021-016
77:03F-023
77:03F-056
77:03F-059
77:03F-060
77:03F-065
77:03F-076
77:03F-079
77:03F-081
77:03F-083
77:03F-086
77:03F-098
77:03F-103
77:03F-134
77:04A-004
77:04A-007
77:04A-020
77:04A-028
77:04A-031
77:04A-032
77:04A-033
77:04A-036
77:04A-039
77:048-015
77:05B-003
77:05B-010
77-.05B-042
77:056-005
77:06C-001
77:060-001
77:08B-006
Sprinklers
77:03F-059
77:03F-134
77:04A-032
Stability
77:02F-007
Standards
77:050-003
77:05G-018
State Government
77:06E-013
Statistical Methods
77 :03F-005
Steady Flow
Stomata
Storage
77:02F-009
77:02F-010
77:04A-023
77:021-010
77:021-011
77:02F-001
77:05B-022
Storage Capacity
77:026-095
Storage Coefficient
77:02F-006
77:02F-017
77 :02F-022
77:02F-037
77:048-007
Storm Runoff
77:02E-004
77:058-005
Storm Water
Storms
77:05B-026
77:02E-004
77:026-095
Stratification
77:02F-015
Stream Erosion
77 :02J-043
Stream 6ages
77:07B-005
Streamflow
77:02E-006
77:026-025
77:02J-002
77:02J-003
77:038-001
Streamflow Forecasting
77:02E-006
Streams
77:02F-046
77:026-025
322
-------
Streams
(cont.)
Sulfates
77-.02J-001
77:02J-002
77:02J-013
77:04A-001
77:04B-003
77:048-012
77:05B-053
77:050-003
Stress
77:02F-006
77:030-001
77:04B-012
Subsidization
77:03F-135
Subsoils
77:02G-173
77:03F-033
Subsurface Drainage
77:02F-032
77:02F-045
77:02G-060
77:040-003
Subsurface Flow
77:02F-003
77:02F-012
77:02F-033
77:02G-018
Subsurface Irrigation
77:02G-026
77:02G-037
77:026-061
77:02G-141
77:03F-023
77:03F-029
77:03F-127
77:04A-004
77:04A-025
Subsurface Runoff
77:05A-003
Subsurface Waters
77:026-025
Suburban Areas
77:058-031
Sugar Beets
77:026-157
77:021-012
77:03F-019
77:03F-112
77:03F-115
77:056-035
77:078-014
Sugarcane
77:03F-033
77:03F-064
77:05B-009
77:02F-016
Sulfur
77:026-085
77:02G-099
77:02G-158
77:03F-015
77:03F-016
Sulfuric Acid
77:026-154
77:05B-040
Summer
77:03B-001
Supplemental Irrigation
77:03F-101
Surface Drainage
77:026-117
77:040-005
77:056-002
Surface Irrigation
77:021-016
77:02J-010
77:02J-037
77:03F-002
77:03F-087
77:03F-097
77:04A-003
77:04A-008
77:04A-017
77:04A-018
77:04A-019
77:04A-020
77:04A-026
77:04A-029
77:04A-030
77:04A-038
77:04A-042
77:058-042
77:056-010
77:060-001
Surface Runoff
77:02G-127
77:04A-042
77:040-003
77:05A-003
77:05G-002
Surface Tension
77:088-011
Surface Waters
77:03F-030
77:04A-001
77:046-003
77:05B-051
Surfaces
Surveys
77:050-005
77:02F-021
Suspended Particles
77:058-051
Suspended Sediments
77:02J-014
Suspended Solids
77:02J-044
77:03F-030
77:04A-028
77:058-026
> 77:050-007
77:056-010
Swelling Soil
77:026-176
Systems Analysis
77:03F-001
77:03F-002
77:03F-005
77:03F-018
77:03F-088
77:048-001
77:048-002
77:048-003
77:048-006
77:04B-008
77:048-012
77:050-003
77:05G-018
Tailwater
77:02J-010
77:04A-020
77:058-037
77:088-001
Technology
77:03F-018
77:03F-027
77:04A-042
77:056-013
77:056-022
77:06A-001
Temperature
Tennessee
77:020001
77:020-008
77:02F-007
77:02F-034
77:026-091
77:026-140
77:021-018
77:02L-001
77:03F-038
77:03F-040
77-.03F-054
77:03F-055
77:03F-058
77:058-022
77:05B-035
77:058-053
77:078-032
77:078-036
77:026-032
323
-------
Tensiometers
77:02D-004
77:026-001
77:02G-008
77:020-016
77:02G-030
77:02G-065
77-.02G-176
77:02I-016
77:03F-010
77:03F-011
77:03F-023
77:03F-042
77:03F-075
77:040-001
Terracing
77:02J-033
77:08B-009
Tertiary Treatment
77:050-005
Test Wells
Testing
77:02F-901
77:05E-001
77:08B-004
77:02G-174
77:02J-011
Testing Procedures
77:02G-174
77:02J-011
77:04D-005
77:05A-010
Texas
77:02F-043
77:026-014
77:04A-004
Theis Equation
77:02F-006
77:04B-007
Theoretical Analysis
77:020-001
77:02F-006
77:02F-012
77:02F-013
77:02F-014
77:026-021
77:026-033
77:026-125
77:02J-042
77:08B-016
Thermal Conductivity
77:02G-006
Thermal Pollution
77:058-007
77:05B-022
77:056-015
Thermal Power
77:04A-041
Thermal Properties
77:02G-005
Thermal Water
77:02F-007
Thermodynamics
77:02G-112
Tile Drainage
77:02F-032
77:02F-045
77:04D-003
77:040-005
77:05A-003
Tiles
Tillage
Time
77:046-002
77:03F-128
77:02B-001
77:02F-040
77:07B-030
Time Lag
77:048-007
Timing
77:078-030
Tomatoes
77:026-105
77:03F-004
Toxicity
77:076-001
Trace Elements
77:021-018
77:05A-006
Tracers
77:026-018
77:02G-023
77:026-024
77:026-054
77:056-002
77:076-001
77:078-029
Translocation
77:03F-006
Transmissivity
77:02F-017
77:02F-022
77:02F-037
77:02F-049
77:02F-051
77:048-007
77:088-004
Transpiration
77:02D-008
77:020-010
77:020-011
77:021-005
77:02L-001
77:038-001
Transpiration Control
77:020-002
77:036-001
Transfer
77:02G-021
77:02G-077
Trap Efficiency
77 :05G-031
Travel Time
77:056-016
Treatment Facilities
77:05E-002
Trickle Filters
77:056-035
Tritium
Turbidity
77:02G-012
77 :026-018
77:026-054
77:058-018
77:078-013
Turbulence
77 :04D-007
77:078-022
Turbulent Flow
77:078-022
77:088-001
Turf
77:026-167
77:03F-076
77:03F-081
77:03F-100
77:03F-104
Turf Grasses
77:03F-081
77:03F-100
Underflow
77:02F-015
Underground Storage
77 :05B-022
77:05E-001
Underseepage
77:02F-015
Uniform Flow
77 :08B-012
Uniformity
77 :03F-028
77:04A-034
Uniformity Coefficient
77:03F-028
77 :08B-012
324
-------
nnsaturated Flow
77:02F-014
77:02F-030
77:02G-003
77:02G-009
77:02G-012
77:02G-013
77:02G-020
77:02G-022
77:02G-024
77:02G-026
77:02G-031
77:02G-033
77:02G-049
77:02G-054
77:02G-060
77:02G-077
77:02G-081
77:02G-094
77:02G-128
77-.02G-137
77:04A-025
77:05D-004
Unsteady Flow
77:02F-009
77:02F-047
77:02F-048
77:02G-125
Urban Runoff
77:02G-095
77:05B-026
Urbanization
77:02F-043
77:02G-095
77:02J-013
77:02J-035
77:03F-026
77:03F-053
77:056-031
77:08C-001
Ureas
Use Rate
Utah
77:028-001
77:02G-062
77:02G-097
77:02G-160
77:02G-163
77:03F-127
77:05G-039
77:02G-078
77:04A-002
77:058-003
77:05G-018
77:056-028
Vapor Pressure
77:02G-007
Variability
77:02G-017
77:02G-018
77:03F-001
77:056-012
77:058-020
Vegetables
77:02G-102
Vegetation
77:02D-007
77:02E-005
77:02G-034
77:02J-032
77:02J-039
Vegetation Effects
77:026-034
77:02J-007
77:02J-032
77:02J-039
Velocity
77:02F-034
77:02J-040
77:04A-028
77:040-007
77:07B-022
77:078-028
77:086-005
Vertical Migration
77:026-029
Viscosity
77:088-011
Voids
77:020001
Vortices
77:04D-007
Washington
77:026-082
77:03F-012
77:03F-085
77:05A-004
77:05G-011
77:056-012
Waste Disposal
77:05D-004
77:05D-007
77:05D-008
77:05E-001
Waste Water
77:048-014
77:050-006
77:06A-002
Waste Water Disposal
77:048-011
77:056-005
77:058-045
77:050-004
77:05E-001
77:05E-002
Waste Water Management
77:03F-007
Waste Water Pollution
77:050-009
Waste Water Treatment
77:05A-009
77:05A-010
77:058-026
77:050-002
77:050-003
77:050-005
77:050-006
77:050-007
77:05E-002
77:06A-003
Wastes
Water
77:056-045
77:02K-002
77:03F-073
77:03F-074
77:03F-077
77:03F-093
77:056-020
77:05G-025
77:06A-002
77:060-001
:06E-009
77;
77:078-001
Water Allocation (Policy)
77:03F-018
77:03F-061
77:03F-088
77:048-008
77:056-003
77:06A-006
77:06E-010
77:.06E-011
Water Analysis
77:058-006
77:058-048
77:078-004
Water Balance
77:026-010
77:026-025
77:04A-039
77:048-002
Water Chemistry
77:02F-016
77:02F-030
77:02F-049
77:05A-009
77:058-031
77:058-043
77:056-004
77:056-015
77:056-033
77:078-001
77 :07B-004
77:078-005
Water Circulation
77:020-008
Water Control
77:04A-039
325
-------
Water Conservation
77:020-011
77:02F-027
77-.03F-009
77:03F-025
77:03F-048
77:03F-066
77:03F-067
77:03F-072
77-.03F-076
77:03F-077
77:03F-081
77:03F-091
77:03F-093
77:03F-097
77:03F-101
77:03F-103
77:03F-105
77:03F-114
77:03F-115
77:03F-117
77:03F-120
77:03F-121
77:03F-122
77:03F-136
77-.04A-020
77:04A-021
77:056-044
77:050-009
77:05G-022
Water Consumption
77:06A-006
Water Costs
77:06E-010
Water Delivery
77:03F-005
77:03F-072
77:03F-088
77:03F-089
Water Demand
77:03F-002
77:03F-073
77:03F-074
77:04B-001
77:05G-018
77:06E-001
Water Distribution (Policy)
77:03F-001
Water Districts
77:05G-003
Water Law
77:05G-022
77:06A-004
77:06A-005
77:06E-004
77:06E-007
77:06E-009
77:06E-011
77:06E-014
Water Levels
77:02F-011
77:02F-019
77:02F-
77:02F-
77-.02F-
77:02F-
77:02G-
77:026-
77:04B-
77:05B-
77:08B-
020
025
037
046
125
128
007
045
009
Water Level Fluctuations
77:02F-013
77:02F-020
Water Loss
77:020-003
Water Management (Applied)
77:02G-096
77:03C-002
77:03F-005
77:03F-007
77:03F-090
77:03F-135
77:04A-009
77:04B-001
77:05A-004
77:058-010
77:05B-046
77:05G-005
77:050-023
77:05G-034
77:06B-002
Water Measurement
77:04A-011
77:04A-039
77:05A-001
77:076-024
77:07B-025
77:078-027
77:07B-028
77:07B-029
Water Policy
77:03F-135
77:05G-018
Water Pollution
77:02E-004
77:02F-050
77:02J-022
77:03F-007
77-.03F-025
77:040-001
77:05A-006
77:058-001
77:058-006
77 :05B-007
77:058-009
77:05B-010
77:058-016
77:05B-019
77:05B-020
77:058-021
77:05B-027
77:05B-031
77:058-034
77:05B-045
77:05B-046
77:058-049
77:05B-056
77:05C-005
77 :05D-006
77:050-008
77:050-009
77:05G-002
77 :05G-015
77 :05G-031
77:05G-038
77:06A-004
77:06E-004
77:06E-008
77:07B-004
77:076-005
Water Pollution Control
77 :02E-004
77:03F-025
77 :03F-057
77:056-021
77:056-023
77:06A-004
77:078-004
Water Pollution Effects
77:03F-057
Water Pollution Sources
77:03F-057
77 :05B-004
77:058-005
77:058-006
77:056-007
77:056-016
77:05B-019
77:056-023
77:056-024
77:058-025
77:058-048
77:058-049
77:056-004
77:056-017
Water Pressure
77:04B-015
Water Properties
77:088-001
Water Quality
77:02E-003
77:02E-004
77-.02F-041
77:02F-049
77:02F-050
77:026-010
77:026-044
77:02G-078
77:02G-103
77:02J-011
77:02J-018
77:02J-022
77:02J-025
77:02J-026
77:02J-031
77:02J-036
77:02J-045
77:03F-024
77:03F-025
326
-------
Water Quality
(cont.)
77:03F-051
77:03F-052
77:03P-062
77:03F-066
77:03F-120
77:04A-003
77:04A-009
77:04A-020
77:04D-002
77:05A-004
77:05A-006
77:05A-007
77:05A-008
77:058-005
77:05B-006
77:056-007
77:05B-009
77:05B-012
77:056-017
77:056-020
77:056-021
77:056-027
77:056-030
77:056-031
77:056-034
77:056-037
77:056-040
77:058-041
77:056-046
77:05B-048
77:056-049
77:058-053
77:05C-001
77:050-002
77:050-003
77:050-004
77:050-006
77:05G-001
77:05G-004
77:05G-008
77:05G-009
77:05G-011
77:05G-012
77:05G-014
77:05G-016
77:05G-019
77:05G-020
77:05G-025
77:05G-027
77:05G-028
77:05G-030
77:05G-033
77:05G-038
77:06A-001
77:06A-002
77:06A-003
77:06A-006
77:06E-002
77:06E-003
77:06E-004
77:06E-005
77:06E-008
77:076-017
77:076-018
Water Quality Control
77-.03F-007
77:03F-024
77:03F-066
77:04A-001
77:046-013
77:05A-008
77:058-012
77:056-037
77:050-003
77:050-006
77:05E-001
77:05G-003
77 :05G-008
77:050-010
77 :05G-014
77:05G-016
77:05G-018
77:05G-022
77:05G-038
77:06A-001
77:06A-003
77:06E-002
77:06E-003
77:06E-004
77:06E-005
77:06E-008
77:076-004
77:078-018
Water Quality Management
77:03F-025
77 :04D-002
Water Quality Standards
77:06E-009
Water Rates
77:03F-135
Water Requirements
77:020-007
77:021-001
77:046-003
Water Resources
77:020-007
77:02E-006
77:02G-034
77:02J-026
77:03F-072
77:03F-076
77:03F-093
77:04A-020
77:04A-022
77:05G-015
77:05G-016
77:05G-022
77:06A-004
77:06A-005
77:06E-004
77:06E-009
77:06E-010
77:06E-011
Water Resources Development
77:048-001
77:06A-004
77:06A-005
77:066-001
77:066-002
Water Reuse
77:046-015
77:050-001
Water Rights
77:05G-003
77:06E-005
77:06E-006
77:06E-014
Water Retention
77:026-176
Water Sampling
77:056-020
77 :07B-002
77:078-005
Water Shortage
77:03F-018
77:04A-020
Water Storage
77:02G-065
77:04A-022
Water Supply
77:03F-003
77:03F-005
77:03F-018
77:03F-072
77:03F-093
77:04A-020
77:04A-022
77:048-001
77:046-003
77:048-008
77:058-020
77:06A-006
77:06E-011
Water Supply Development
77:03F-093
Water Table
77:020-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:02F-
77:026-
77:026-
77:026-
77:026-
77:03F-
77:03F-
77:03F-
77:04A-
77:048-
77:048-
77:048-
77:058
77:058
77:075
77:078
007
001
004
008
009
Oil
018
019
032
045
025
-048
-125
126
-019
037
064
025
-002
-004
005
-045
-056
-002
-021
Water Temperature
77:02F-007
77:02F-034
77:036-007
327
-------
"ater Use
77 :05G-039
Water Users
77:020-007
Water Utilization
77:020-007
77:02G-096
77:021-016
77:03F-004
77:04B-008
Water Vapor
77:02G-006
77:026-007
Water Wells
77:02F-001
77:02F-019
77:02F-023
77:02F-047
77:02F-048
77:048-007
77:048-011
77:05A-007
77:058-016
77:05B-020
77:056-031
Water Yield
77:05G-003
77:088-004
Watershed Management
77:040-002
77:058-033
77:05G-002
77:078-009
Watersheds
77:02E-003
77:02G-093
77:040-002
77:05B-033
77:050-023
77:06A-005
Watersheds (Basins)
77:020-001
77:02E-004
77:02E-005
77:02G-014
77:026-127
77:02G-142
77:02J-013
77:02J-041
77:02J-042
77:02J-046
77:038-001
77:03F-024
77:040-003
77:04D-006
77:058-027
77:05G-026
77:078-009
Waves (Water)
77:088-001
Weather Data
77:020-001
77:048-002
Weed Control
77:03F-087
77:03F-133
77:05G-002
Weirs
77:04A-011
77:07B-024
77:07B-025
77:078-027
77:088-005
77:088-011
77:08B-016
Well Screens
77:02F-019
Well Spacing
77:088-004
Wellpoints
77:078-002
Wells
Wetting
Wheat
77:02F-017
77:02F-019
77:02G-025
77:04A-001
77:048-001
77:048-004
77:048-006
77:04B-011
77:05A-007
77:058-016
77:058-018
77:058-022
77:058-031
77:02G-011
77:02G-035
77:02G-056
77:02G-058
77:02G-074
77:026-005
77:02G-156
77:026-161
77:02G-162
77:02G-166
77:02I-002
77:03F-032
77:03F-034
77:03F-035
77:03F-036
77:03F-043
77:03F-054
Wildlife
77:02G-073
77:03F-119
Wildlife Conservation
77:02G-073
Wildlife Habitats
77:02G-073
77:03F-119
Wildlife Management
77:03F-119
Wind Velocity
77 :02D-006
77:02G-007
77:03F-034
77:03F-035
77:09C-001
Windbreaks
Winds
Wisconsin
77 :03F-034
77:03F-035
77:020-006
77:03F-045
77:03F-056
77:048-005
77:05B-017
Withdrawal
Wyoming
Zinc
77:020-005
77:02F-011
77:04B-005
77:03F-077
77:02G-086
77:02G-169
77:03F-032
77:05A-006
323
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TECHNICAL REPORT DATA
If lease read Instructions on the reverse before completing*
EPA-600/2-79-020
4. TITLE AND SUBTITLE
|3. RECIPIENT'S ACCESSION-NO.
SELECTED IRRIGATION RETURN PLOW QUALITY
ABSTRACTS 1977, Seventh Annual Issue
5. REPORT DATE
January 1979 issuing date
6. PERFORMING ORGANIZATION CODE
V. Skogerboe, Stephen w. Smith,
Wynn R. Walker, and Sue Eastman
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Department of Agricultural and Chemical
Engineering
Colorado State University
Fort Collins, Colorado 80523
12. SPONSORING AGENCY NAME AND ADDRESS
Robert S. Kerr Environmental Research
Office of Research and Development
U.S. Environmental Protection Agency
Ada, Oklahoma 74820
Lab
10. PROGRAM ELEMENT NO.
1BB770
11. CONTRACT/GRANT NO.
Grant No. R-800426
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/600/15
15. SUPPLEMENTARY NOTES
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 Irrigated
Crop Production research and development program. These articles de-
scribe 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 sec-
ond annual issue lists publications printed in 1970 and 1971, the third
annual issue covers calendar years 1972 and 1973, and the fourth, fifth,
and sixth annual issues cover literature published in 1974, 1975, and
1976. This annual issue lists publications printed in 1977.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
' b.IDENTIFIERS/OPEN ENDED TERMS
Fertilizers, Irrigated land,
Salinity
Irrigation systems,
Irrigation water, Ni-
trates, Phosphates,
Return flow, Water
pollution effects,
Water pollution
sources, Water qualitjy
:,o.n1-rQl
COSATI Field/Group
98C
48E
68D
13. DISTRIBUTION STATEMENT
Release to Public
1£. SECURITY CLASS (This Report)
Unclassified
21 NO. OF Pfi
339
5ES
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
329
U.S. GOVERNMENT PRINTING OFFICE: 1979 657-060/1571
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