Water Quality Information Center of the National Agricultural Library
Agricultural Research Service, U.S. Department of Agriculture

Evaluation of Best Agricultural Management Practices (II)

 1990 - SEPTEMBER 1995
 141 citations from AGRICOLA
 Diane Doyle
 Water Quality Information Center
 This electronic bibliography is intended primarily to provide
 awareness of recent investigations and discussions of a topic and
 is not intended to be in-depth and exhaustive. The inclusion or
 omission of a particular publication or citation should not be
 construed as endorsement or disapproval. 
 Send suggestions for electronic bibliographies related to water
 resources and agriculture to wqic@nalusda.gov
 To locate a publication cited in this bibliography, please
 contact your local, state, or university library.  If you are
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 contact the National Agricultural Library (please see "Document
 Delivery Services" at 
 1. Adoption of nitrogen and water management practices to improve
 water quality.
 Supalla, R. J.; Selley, R. A.; Bredeweg, S.; Watts, D. 
 J-soil-water-conserv v.50, p.77-82. (1995).
 Includes references.
 Descriptors: zea-mays; irrigated-stands; nitrogen-;
 crop-management; nitrogen- fertilizers; application-to-land;
 water-management; nitrate-; leaching- ; losses-from-soil;
 groundwater-pollution; water-quality; farmers'- attitudes;
 environmental-protection; nebraska-; nitrogen-management
 NAL Call No.:  56.8-J822
 2. Agricultural use of organic amendments: a historical
 Parr, J. F.; Hornick, S. B. 
 Am-J-Alternative-Agric v.7, p.181-189. (1992).
 Includes references.
 Descriptors: organic-fertilizers; history-; erosion-;
 composting-; soil-organic- matter; sewage-sludge; solid-wastes;
 Abstract: Agricultural research conducted in the United States
 since establishment of the U.S. Dept. of Agriculture and
 Land-Grant  University System in 1862 has shown that regular and
 proper additions  of organic materials are very important for
 maintaining the tilth,  fertility, and productivity of
 agricultural soils, protecting them from  wind and water erosion,
 and preventing nutrient losses by runoff and  leaching. Several
 millennia earlier, Roman agriculturists were  advocating crop
 rotations, green manuring, composts, legumes, farmyard  manures,
 crop residues, wood ashes, seaweed, and sewage wastes for 
 supplying humus and nutrients to restore or enhance soil
 productivity.  Even earlier, Asian farmers also used these
 practices to maintain  healthy and productive soils. Today the
 most serious problem in U.S.  agriculture and agriculture
 worldwide is the widespread degradation of  agricultural soils
 through erosion and the consequential decline in  productivity.
 In view of how much information is available on the  benefits of
 organic recycling on agricultural lands, one wonders why we 
 aren't doing a better job of protecting and conserving our land 
 resource base. We discuss strategies for using organic resources
 more  effectively to achieve a more sustainable agriculture for
 the future.
 NAL Call No.:  S605.5.A43
 3. Agriculture and water quality in the Great Plains: status and 
 Misc-publ,-Tex-Agric-Exp-Stn. College Station, Tex. : Texas 
 Agricultural Experiment Station. Mar 1992. (1738) 34 p. 
 Includes references.
 Descriptors: water-quality; agricultural-chemicals;
 water-pollution; groundwater- ; surface-water; irrigation-;
 livestock-farming; conservation-tillage; agricultural-planning;
 state-government; federal-government; agricultural-research;
 agricultural-policy; legislation-; agricultural- regions;
 northern-plains-states-of-usa; southern-plains-states-of-usa;
 NAL Call No.:  100-T31M
 4. Analysis of on-farm best management practices in the
 Everglades  Agricultural Area.
 Willis, L. M.; Forrest, S. B.; Nissen, J. A.; Hiscock, J. G.;
 Kirby, P. V. 
 Environmentally sound agriculture proceedings of the second 
 conference  20-22 April 1994 / p.93-99. (1994).
 Includes references.
 Descriptors: marshes-; environmental-protection;
 agricultural-land; management-; cost-effectiveness-analysis;
 phosphorus-; discharge-; water-flow; water- quality;
 improvement-; sustainability-; florida-; nutrient-loadings
 NAL Call No.:  S589.7.E57-1994
 5. Animal waste system management in Southwest Missouri.
 Feistner, J. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1991. (914570) 10 p. 
 Paper presented at the "1991 International Winter Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 December 17-20,  1991, Chicago, Illinois.
 Descriptors: animal-manures; animal-wastes; water-quality;
 environmental-impact; missouri-
 NAL Call No.:  290.9-Am32P
 6. Application of GLEAMS to predict nutrient losses from land 
 application of poultry litter.
 Yoon, K. S.; Yoo, K. H.; Wood, C. W.; Hall, B. M. 
 Trans-ASAE v.37, p.453-459. (1994).
 Includes references.
 Descriptors: poultry-manure; runoff-; nitrogen-; phosphorus-;
 water-quality; simulation-models; alabama-;
 groundwater-loading-effects-of-agricul; -manage; -systems
 Abstract: The GLEAMS (Groundwater Loading Effects of Agricultural
 Management  System) (version 2.1) water quality model was used to
 predict nutrient  (N and P) losses in surface and subsurface
 runoff, and their  concentrations in soil layers, following
 application of two rates (9  and 18 t ha-1) of poultry litter and
 a recommended rate of a commercial  fertilizer on conventionally
 tilled corn plots at the Tennessee Valley  Substation of the
 Alabama Agricultural Experiment Station. Model  simulation
 results were compared with field data. The experiment  included
 four replications for each of the three soil-amendment 
 treatments. The GLEAMS simulation of soluble and sediment P
 losses in  surface runoff and NO3-N concentrations in leachate
 and soil layers  were not consistent with field data. Simulation
 of N-transformation  effects on N losses in surface runoff did
 not agree with field data.  The model simulated higher NH4-N than
 NO3-N losses in surface runoff,  while field data showed the
 opposite. The model simulated low  concentrations of P in
 leachate at a 1.0 m depth, while the observed  data showed large
 NAL Call No.:  290.9-Am32T
 7. Assessing phosphorus bioavailability in agricultural soils and 
 Sharpley, A. N. 
 Fertil-res. Dordrecht : Kluwer Academic Publishers. 1993. v. 36
 (3)  p. 259-272. 
 Includes references.
 Descriptors: phosphorus-; bioavailability-; estimation-;
 agricultural-soils; runoff-; analytical-methods; iron-oxides;
 water-quality; eutrophication- ; risk-; no-tillage-; tillage-;
 watershed-management; algae-; nutrient- availability;
 conventional-tillage; iron-oxide-strips
 Abstract: Bioavailable phosphorus (BAP) transported in
 agricultural runoff  can accelerate surface water eutrophication.
 Although several algal  assays and chemical extractions have been
 proposed to estimate BAP,  procedural and theoretical limitations
 have restricted widespread BAP  measurement. Thus, a routine
 method was developed to estimate BAP,  which uses iron
 oxide-impregnated paper strips (Fe-oxide strips) as a P- sink for
 BAP in runoff. In the proposed method BAP is determined by 
 shaking 50 mL of unfiltered runoff with one Fe-oxide strip for 16
 h.  Phosphorus is removed from the strip by 0.1 M H2SO4 and
 measured. The BAP content of runoff from 20 agricultural
 watersheds in the Southern  Plains was related to the growth of
 P-starved algae incubated for 29 d  with runoff as the sole
 source of P. Acting as a P sink, Fe-oxide  strips may have a
 stronger theoretical basis than chemical extraction  in
 estimating BAP. The method may also have potential use as an 
 environmental soil P test to indicate soils liable to enrich
 runoff  with sufficient P to accelerate eutrophication.
 Bioavailable P loss in  runoff was lower from no till (438 g ha-1
 yr-1) than from conventional  till (1288 g ha-1 yr-1). Kinetic
 and enrichment ratio approaches  accurately predicted (r2 of
 0.93) BAP transport in runoff during 1988  to 1990. Use of the
 Fe-oxide strip method will facilitate estimation of  BAP
 transport in runoff and thereby, improve assessment of the 
 resultant impact on the biological productivity of receiving
 surface  waters.
 NAL Call No.:  S631.F422
 8. Assessment of management practices for reducing pesticide
 runoff  from sloping cropland in Illinois.
 Felsot, A. S.; Mitchell, J. K.; Kenimer, A. L. 
 J-Environ-Qual v.19, p.539-545. (1990).
 Includes references.
 Descriptors: alachlor-; carbofuran-; terbufos-; runoff-;
 losses-from-soil; sediment-; runoff-water; conservation-tillage;
 no-tillage-; chiselling- ; ridging-; plowing-;
 contour-cultivation; row-orientation; sloping- land; zea-mays;
 glycine-max; illinois-; strip-till-
 Abstract: The influence of tillage system and contouring practice
 on runoff  of soil-applied alachlor
 [2-chloro-2',6'-diethyl-N-(methoxymethyl)  acetanilide],
 carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl 
 methylcarbamate), and terbufos (S-[(tert-butylthio)methyl]
 O,O-diethyl  phosphorodithioate) from small plots (30 m2) were
 studied using a  rainfall simulator. Plots were planted in corn
 (Zea mays L.) in 1983,  soybean [Glycine max (L.) Merr.] in 1984,
 and corn in 1985. Runoff was  measured during a 60-min event with
 a rainfall intensity of 63 mm/h.  During 1984, moldboard-plowed
 and no-till systems were studied with  rows oriented on the
 contour or up-and-down slope (7-11% slope).  Compared to
 moldboard plow, up-and-down slope no-till and contouring 
 significantly reduced runoff of carbofuran and alachlor.
 Percentage of  applied carbofuran lost in runoff and sediment
 ranged from 1% (contoured moldboard) to 11% (up-and-down slope
 moldboard). Percentage of applied alachlor lost ranged from 1%
 (contoured no-till) to 2%  (contoured moldboard). During 1985,
 the effects of row orientation were  evaluated on moldboard-plow,
 chisel-plow, ridge-till, strip-till, and  no-till systems. Under
 up-and-down slope conditions, runoff of alachlor  and terbufos
 plus two metabolites (terbufos sulfoxide and terbufos  sulfone)
 was significantly reduced by strip-till (< 1% loss) compared  to
 moldboard-plow (6% loss). Larger losses of alachlor (2% of
 applied)  from up-and-down slope no-till than from the other
 conservation tillage  systems 1% or less) was attributed to high
 concentrations in runoff  associated with extensive washoff of
 the herbicide from soybean crop  residues. With contouring, ridge
 tillage also was effective in reducing  pesticide runoff (< 1% of
 applied pesticide), and strip-till held  losses to < 0.1%.
 Alachlor and carbofuran were translocated from plots  largely in
 moving water, but terbufos and metabolites were recovered  mainly
 in eroded sediment. Although, no conservation tillage system 
 completely eliminated esticide runoff, losses were most
 effectively  minimized by contoured strip-till and no-till, which
 controlled both  water and sediment movement.
 NAL Call No.:  QH540.J6
 9. Atrazine leaching and its relation to percolation of water as 
 influenced by three rates and four methods of irrigation water 
 Troiano, J.; California. Environmental Hazards Assessment
 Program. Worker Safety. Environmental Monitoring and Pest
 Management Branch. 
 Sacramento, Calif. : State of California, Dept. of Food and 
 Agriculture, Division of Pest Management, Environmental
 Protection and  Worker Safety, Environmental Monitoring and Pest
 Management Branch,  [1990] vi, 51 p. : ill..
 "July, 1990.".
 Descriptors: Soils-California-Herbicide-movement;
 Soil-percolation-California; Groundwater-Pollution-California;
 NAL Call No.:  S592.6.H47A87--1990
 10. Barley performance under heavy applications of cattle feedlot 
 Chang, C.; Sommerfeldt, T. G.; Entz, T. 
 Agron-j v.85, p.1013-1018. (1993).
 Includes references.
 Descriptors: hordeum-vulgare; cattle-manure; feedlot-wastes;
 waste-utilization; application-rates; clay-loam-soils;
 application-date; timing-; incorporation-; tillage-; crop-yield;
 grain-; yield-increases; irrigated-conditions; dry-conditions;
 soil-pollution; water-pollution; alberta-
 Abstract: Approximately 4800 cattle feedlots currently operate in
 Alberta,  Canada. The large amount of manure   produced annually
 creates disposal  problems for feedlot operators. The objective
 of the present  study was  to evaluate the effects of long-term
 annual manure application on  barley (Hordeum vulgare   L.)
 performance grown on clay loam soil (Dark  Brown Chernozemic,
 Typic Haploboroll) near   Lethbridge, AB. Feedlot  cattle manure
 was applied annually from 1973 to 1989 to irrigated plots  at  
 0, 60, 120, and 180 Mg ha-1 (wet wt. basis) and to nonirrigated 
 plots at 0, 30, 60, and Mg ha-1.  Manure was incorporated with a 
 cultivator plus disk, rototiller, or plow. Method of
 incorporation did not affect barley yields, but timeliness and
 amount of precipitation in the current and previous year were
 important in determining barley response to manure treatments.
 When moisture conditions were below normal, manure at any rate of
 application had a  negative effect on yield of nonirrigated
 barley. Under nonirrigated  conditions, average barley yield was
 depressed by 10 and  16% for the  60 and 90 Mg ha-1 manure rates,
 respectively. Barley yield increased  when manure was   applied
 under irrigation, with the 60 Mg ha-1 rate  producing a 20%
 higher average yield than the   control. Although  manure was
 disposed of annually on the soil at up to three times the 
 recommended   rate without reducing barley yields below those of
 the  unmanured plots under irrigated conditions, such practice is
 not  recommended because of potential soil and water pollution.
 NAL Call No.:  4-AM34P
 11. Beef cattle feedlot manure management.
 Eghball, B.; Power, J. F. 
 J-soil-water-conserv v.49, p.113-122. (1994).
 Includes references.
 Descriptors: beef-cattle; cattle-manure; feedlot-wastes;
 waste-utilization; resource-management; uses-;
 application-to-land; environmental-impact;
 environmental-protection; nitrogen-; recovery-;
 pollution-control; nutrient-conservation
 NAL Call No.:  56.8-J822
 12. Best management practices (BMP) evaluation using GIS-CREAMS
 Bekdash, F. A.; Shirmohammadi, A.; Magette, W. L.; Ifft, T. H. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1991. (91-7516) 20 p. 
 Paper presented at the "1991 International Winter Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 December 17-20,  1991, Chicago, Illinois.
 Descriptors: pollution-; geographical-information-systems;
 NAL Call No.:  290.9-Am32P
 13. Best management practices for agricultural nonpoint source
 control.  IV, Pesticides : for the project Rural Nonpoint Source
 Control Water  Quality Evaluation and Technical Assistance
 (National Water Quality  Evaluation Project).
 United States. Environmental Protection Agency. Office of
 Research and Development. 
 Washington, DC : U.S. Environmental Protection Agency, Office of 
 Research and Development, [1992] xiii, 87 p..
 Shipping list no.: 92-268-P.
 Technical-Assistance-Project; Pesticides-
 NAL Call No.:  TD427.P35B46-1992
 14. Best management practices for forested wetlands in the
 Southern  Appalachian Region.
 Aust, W. M. 
 Water-air-soil-pollut v.77, p.457-468. (1994).
 In the special issue: Wetlands of the interior southeastern
 United  States / edited by C.C. Trettin, W.M. Aust, and J.
 Wisniewski. Conference on "Wetland Ecology, Management, and
 Conservation," held  September 28-30, 1993, Knoxville, Tennessee.
 Descriptors: wetlands-; riparian-forests; bottomland-forests;
 forest-management; environmental-degradation;
 protection-of-forests; forestry-practices; environmental-impact;
 logging-effects; southeastern-states-of-usa;
 NAL Call No.:  TD172.W36
 15. Biogeochemical responses of a forested watershed to both
 clearcut  harvesting and papermill sludge application.
 Kraske, C. R.; Fernandez, I. J. 
 J-environ-qual v.22, p.776-786. (1993).
 Includes references.
 Descriptors: paper-mill-sludge; application-to-land; forests-;
 watersheds-; clearcutting-; forest-soils; pinus-resinosa;
 soil-ph; soil-organic- matter; calcium-; magnesium-;
 cation-exchange-capacity; sulfates-; biogeochemistry-; maine-
 Abstract: The biogeochemical responses of a forested watershed to
 both  clearcut harvesting and papermill   sludge application were
 evaluated.  A mixed northern hardwood and conifer stand in Letter
 E  Township, ME,  was clearcut during the winter of 1985-1986.
 Harvest residues were  windrowed, and red   pine (Pinus resinosa
 Aiton) seedlings were  planted. In 1987, herbicide was applied to
 reduce  vegetative  competition. In the fall of 1989, a combined
 primary and secondary  papermill sludge was   operationally
 applied with a rate of 40 Mg ha-1  (dry sludge). Actual loading
 rates varied   considerably. Study plots  were established in
 sludge-harvest, control-harvest, and uncut forest    zones. Soils
 within the treatment zones consisted of Typic Haplorthods 
 developed from loamy basal   tills. Selected soil and soil
 solution  properties were measured in 1989 and 1990. In 1989,
 harvest   area  forest floor pH was 0.6 to 0.8 units higher, and
 organic matter content  was up to 40% lower,   when compared with
 that of the uncut forest  area. This reflected the accelerated
 decomposition of   the forest  floor as a result of the harvest
 activities. Sludge application further  increased  forest floor
 pH by approximately one unit, exchangeable Ca2+  and Mg2+ by
 approximately 100 and 60%, respectively, cation-exchange 
 capacity by 60%, and base saturation by 34% compared with that of 
  the  control-harvest area. Exchangeable Mg2+ and Na+, and
 water-soluble SO4(- 2) were the mineral   soil properties most
 affected by sludge  application. Harvesting increased
 concentrations of major. times greater, and Mg2+ was   three to
 six times greater in the harvest  area than in the uncut forest
 area. Flushes of Ca2+,   Mg2+, Na+, and  SO4(-2) into soil
 solution occurred immediately following sludge  application. Only 
 Na+ and SO4(-2) remained elevated in 1990, being  five and three
 times greater, respectively, in the   sludge amended  harvest
 area than in the uncut forest area. Compared with the harvest 
 operations,  one-time papermill sludg application appeared to
 have  only small effects on the biogeochemical   processes of the
 treated  Letter E site.
 NAL Call No.:  QH540.J6
 16. BMP impacts on watershed runoff, sediment, and nutrient
 Park, S. W.; Mostaghimi, S.; Cooke, R. A.; McClellan, P. W. 
 Water-resour-bull v.30, p.1011-1023. (1994).
 Includes references.
 Descriptors: watersheds-; pollution-; runoff-; sediment-;
 nutrients-; water- quality; catchment-hydrology; virginia-;
 best-management-practice; agricultural-nonpoint-source-pollution
 Abstract: To quantify the effectiveness of best management
 practice (BMP) implementation on runoff, sediment, and nutrient
 yields from a  watershed, the Nomini Creek watershed and water
 quality monitoring project was initiated in 1985, in Westmoreland
 County, Virginia. The  changes in nonpoint source (NPS) loadings
 resulting from BMPs were  evaluated by comparing selected
 parameters from data series obtained  before, during, and after
 periods of BMP implementation. The results  indicated that the
 watershed-averaged curve number, sediment, and  nutrient (N and
 P) concentrations were reduced by approximately 5, 20,  and 40
 percent, respectively, due to BMP implementation. The nutrient 
 yield model developed by Frere et al. (1980) was applied to the
 water  quality parameters from 175 storms, but it failed to
 adequately  describe the observed phenomena. Seasonal changes in
 nutrient  availability factors were not consistent with field
 conditions, nor  were they significantly different in the pre-
 and post-BMP periods. An  extended period of monitoring, with
 intensive BMP implementation over a  larger portion of the
 watershed, is required to identify RMP  effectiveness.
 NAL Call No.:  292.9-Am34
 17. BMPs for water quality : best management practices to reduce
 runoff  of pesticides into surface water : a review and analysis
 of supporting  research.  Best management practices to reduce
 runoff of pesticides into  surface water.
 Christensen, B.; Conservation Technology Information Center. 
 [West Lafayette, Ind.] : Conservation Technology Information 
 Center, [1992 or 1993?] i, 43 p. : ill..
 Cover title.
 Descriptors: Pesticides-Environmental-aspects-United-States;
 Water-Pollution- United-States;
 NAL Call No.:  TD427.P35B57--1992
 18. Changes in physical and chemical characteristics of poultry
 litter  due to rotary tilling.
 Koon, J. L.; Flood, C. A. Jr.; McCaskey, T. A.; Brewer, R. N. 
 Trans-ASAE v.37, p.269-274. (1994).
 Includes references.
 Descriptors: poultry-manure; litter-; rotary-cultivators;
 physical-properties; chemical-properties
 Abstract: Pine shavings poultry litter from four growouts were
 analyzed for  particle size distribution and chemical composition
 for untilled litter  and litter that had been tilled three times
 following each growout.   Little change in the particle size
 distribution was observed after the  first growout for either
 treatment.  The majority of the nutrient mass  was associated
 with the larger size particles (those failing to pass a  No. 50
 screen) while the percent element analysis increased with the 
 smaller size fractions for both treatments.  Little change in
 nutrient  content was observed between treatments, but the tilled
 liner had an  increase in percent ash content and a decrease in
 percent crude fiber.   No difference was observed in the crude
 protein percentage in the two  treatments.
 NAL Call No.:  290.9-Am32T
 19. Changing farm practice to meet environmental objectives of
 nutrient  loss to Oyster Harbour.
 Weaver, D. M.; Prout, A. L. 
 Fertil-res. Dordrecht : Kluwer Academic Publishers. 1993. v. 36
 (2)  p. 177-184. 
 In the special issue: Fertilizers and eutrophication in South-
 Western Australia / edited by E.P. Hodgkin and J.S. Yeates.
 Descriptors: watershed-management; agricultural-land; nutrients-;
 phosphorus-; losses-from-soil; point-sources; farm-management;
 environmental- management; water-quality; eutrophication-;
 western-australia; on-farm-nutrient-management; nonpoint-sources
 Abstract: Eutrophication problems in waterbodies in south-western
 Australia  are primarily caused by inputs of nutrients from
 diffuse sources within  the agricultural catchments of these
 waterbodies. To reduce the algal  growth and seagrass decline
 caused by these inputs, it is essential to  modify land
 management to minimize nutrient losses. Permanent reduction  in
 nutrient losses from agricultural catchments should involve 
 voluntary changes in farm management practices based on improved
 land  management. Specifically, these include on-farm nutrient
 management  such as soil testing, fertilizer management, the use
 of perennial  plants, and water and erosion control measures to
 reduce nutrient loss  from rural land. This paper describes the
 management of nutrient loss  from the catchment of Oyster Harbour
 on the south coast of Western  Australia using a co-operative
 NAL Call No.:  S631.F422
 20. A comparative study of nitrate leaching from soils of
 differing  textures under similar climatic and cropping
 Vinten, A. J. A.; Vivian, B. J.; Wright, F.; Howard, R. S. 
 J-hydrol v.159, p.197-213. (1994).
 Special Issue: Field laboratory and modelling studies of flow and 
 transport processing / edited by H.S. Wheater, P.A.C. Raats, and
 A.C.  Armstrong. Sciences Programme Session HS1 of the XVII
 General Assembly of the  European Geophysical Society, April
 6-10, 1992, Edinburgh.
 Descriptors: nitrate-nitrogen; leaching-; sandy-soils;
 clay-loam-soils; nitrogen- fertilizers; application-rates;
 hordeum-vulgare; cultivation-; timing-; drainage-water;
 flow-to-drains; losses-from-soil; groundwater-pollution
 Abstract: This study reports a direct comparison of nitrate
 leaching on a  field scale from a sandy soil overlying a
 relatively impermeable  glacial till (Ksat = 30-50 mm day-1),
 with that from a clay loam soil  overlying a similar glacial till
 (Ksat = 2-8 mm day-1), under nearly  identical climatic and
 cropping conditions. Drained plots were  installed at each site,
 and N application rate on the plots, which grew  spring barley,
 varied from 0 to 210 kg N ha-1. Nitrate concentrations  in
 drainage water from the two sites were measured using a simple
 flow- weighted sampling device and drainflow was measured using
 tipping  bucket flow meters. Total leaching losses (including an
 estimate of  deep percolation) in the first year of the
 comparison were not  significantly higher on the sandy site (38
 +/- 11 kg N ha-1 at 150 kg N  ha-1 N fertiliser application) than
 on the clay loam site (27 +/- 4 kg  N ha-1). In the subsequent 2
 years, leaching losses increased at the  sandy loam site. At the
 clay loam site leaching losses were much lower  (7-11 kg N ha-1
 in the final year). Timing of cultivation was an  important
 factor influencing the amount of leaching in the clay loam  soil.
 The effect of applied N fertiliser on nitrate leaching was small 
 at both sites, except in the final year at the sandy site, which 
 leached 105 kg N ha-1 at the highest fertiliser rate. The 
 interpretation of these results was aided by concurrent chloride 
 leaching experiments. These experiments showed that the residence
 time  of a substantial proportion of chloride (40-50%) was longer
 than 1  year. This may be because of diffusion and slow
 convection into the  glacial till horizons, where the residence
 time is long.
 NAL Call No.:  292.8-J82
 21. Components of dairy manure management systems.
 Van Horn, H. H.; Wilkie, A. C.; Powers, W. J.; Nordstedt, R. A. 
 J-dairy-sci v.77, p.2008-2030. (1994).
 Includes references.
 Descriptors: cattle-manure; dairy-farms; application-to-land;
 dairy-cows; excretion-; waste-treatment; waste-disposal;
 waste-utilization; energy- balance; water-use; ammonia-;
 methane-; nitrogen-; phosphorus-
 Abstract: Dairy manure management systems should account for the
 fate of  excreted nutrients that may be of environmental concern.
 Currently,  regulatory oversight is directed primarily at the
 assurance of water  quality; N is the most monitored element.
 Land application of manure at  acceptable fertilizer levels to
 crops produced on the farm by hauling  or by pumping flushed
 manure effluent through irrigation systems is the  basis of most
 systems. Nutrient losses to surface and groundwaters can  be
 avoided, and significant economic value can be obtained from
 manure  as fertilizer if adequate crop production is possible.
 Dairies with  insufficient crop production potential need
 affordable systems to  concentrate manure nutrients, thereby
 reducing hauling costs and  possibly producing a salable product.
 Precipitation of additional  nutrients from flushed manures with
 sedimented solids may be possible.  Composting of separated
 manure solids offers a possible method to  stabilize solids for
 distribution, but, most often, solids separated  from dairy
 manures are fibrous and low in fertility. Manure solids  combined
 with wastes from other sources may have potential if a 
 marketable product can be produced or if sufficient subsidy is
 received  for processing supplementary wastes. Solutions to odor
 problems are  needed. Energy generated from manure organic
 matter, via anaerobic  digestion, reduces atmospheric emissions
 of methane and odorous  compounds. Use of constructed wetlands or
 harvesting of photosynthetic  biomass from wastewater has the
 potential to improve water quality,  making extensive recycling
 NAL Call No.:  44.8-J822
 22. Concepts and practices for improving nitrogen management for 
 Hochmuth, G. J. 
 HortTechnology v.2, p.121-125. (1992).
 Proceedings of the Workshop, "Fertilizer in Horticultural Crops: 
 Implications for Water Pollution," held at the 88th ASHS Annual 
 Meeting, July 24, 1991, Pennsylvania State University, University
 Descriptors: nitrogen-fertilizers; vegetables-; crop-production;
 water- management; groundwater-pollution; organic-amendments;
 nitrification- inhibitors; cultivars-; cropping-systems;
 trickle-irrigation; plant- analysis; literature-reviews;
 NAL Call No.:  SB317.5.H68
 23. Conservation tillage a sustainable agricultural practice.
 Lakshminarayan, P. G.; Bouzaher, A.; Johnson, S. R. 
 Environmentally sound agriculture  proceedings of the second 
 conference  20-22 April 1994 / p.139-146. (1994).
 Includes references.
 Descriptors: zea-mays; glycine-max; continuous-cropping;
 rotations-; conservation-tillage; tillage-; environmental-impact;
 sustainability-; erosion-; erosion-control; nitrate-nitrogen;
 losses-from-soil; leaching- ; runoff-; water-quality;
 simulation-models; statistical-analysis; conventional-tillage;
 NAL Call No.:  S589.7.E57-1994
 24. Conservation tillage: an ecological approach to soil
 Blevins, R. L.; Frye, W. W. 
 Adv-agron. San Diego, Calif. : Academic Press. 1993. v. 51 p.
 Includes references.
 Descriptors: conservation-tillage; no-tillage-; soil-management;
 soil- conservation; water-conservation; water-quality;
 energy-consumption; soil-organic-matter;
 soil-physical-properties; soil-water; infiltration- ;
 evaporation-; herbicides-; weed-control; insect-control; plant-
 disease-control; soil-fertility; soil-temperature; soil-ph;
 acidification-; literature-reviews
 NAL Call No.:  30-Ad9
 25. Conservation tillage and environmental issues.
 Schertz, D. L. 
 Yearb-agric. Washington, D.C. : U.S. Dept. of Agriculture : For 
 sale by the Supt. of Docs., U.S. G.P.O., [1980-. 1991.  p. 15-20. 
 In the series analytic: Agriculture and the Environment / edited
 by  D. Takiff Smith.
 Descriptors: conservation-tillage; erosion-control;
 environmental-impact; water- pollution; agricultural-chemicals;
 movement-in-soil; losses-from-soil
 NAL Call No.:  1-Ag84y
 26. Corn yield and nitrogen uptake as influenced by tillage and
 applied  nitrogen.
 Menelik, G.; Reneau, R. B. Jr.; Martens, D. C. 
 J-plant-nutr v.17, p. 911-913. (1994).
 Includes references.
 Descriptors: zea-mays; tillage-; no-tillage-;
 urea-ammonium-nitrate; application- rates; split-dressings;
 sewage-sludge; sewage-products; nutrient- uptake; crop-yield;
 nitrogen-; conventional-tillage
 Abstract: No-till management systems have been reported to reduce
 nonpoint  source (NPS) pollution from agricultural fields.
 However, questions  have been raised concerning the fate of
 nitrogen (N) in these systems.  increased moisture conservation
 and reduced runoff from no-till systems  have the potential to
 accelerate leaching of nitrate (NO3) out of the  root zone, thus
 altering the problem from one of surface water  degradation to
 one of ground water pollution. However, it is also  probable that
 the additional moisture conserved in no-till systems  result in
 increased crop yield and N uptake. Time of N application and 
 source of N could influence yield and N recovery and thus limit N 
 losses during critical periods. A 3-year study was conducted to 
 determine if the fate of N applied to nonirrigated corn (Zea mays
 L.)  would be influenced by tillage system, N rate, and time and
 source of N  application. This paper addresses the impact of
 these practices on  yield and N uptake. The experimental site was
 located on a Typic  Hapludult that is characteristic of
 finer-textured soils used for  continuous corn production.
 Management practices evaluated were  conventional-till vs.
 no-till, rate of N application, inorganic N vs.  sewage sludge N,
 and preplant vs. split application of N. Yield and N  recovery
 were, respectively, 19 and 22% higher in no-till compared with 
 conventional-till systems at the point of maximum yield. Corn
 yield and  N uptake were both increased when sewage sludge was
 applied compared  with either split or preplant application of
 inorganic N. No  differences were observed in corn yield and N
 uptake between preplant  and split application of N. These
 studies were conducted. indicate that the higher moisture present
 in the no-till system may  have contributed to increased yield
 and N recovery. The increased N  recovery reduces the quantity of
 N remaining in the soil profile that  might be lost, due to
 leaching, after crop harvest.
 NAL Call No.:  QK867.J67
 27. Crop, soil, and management effects on phosphorus soil test
 Pierzynski, G. M.; Logan, T. J. 
 J-prod-agric v.6, p.513-520. (1993).
 Paper presented at the "Symposium on assessment of potential 
 phosphorus losses from a field site", November 4, 1992,
 Minneapolis,  Minnesota.
 Descriptors: phosphorus-; soil-test-values; variation-; crops-;
 soil-; crop- management; soil-management; site-factors;
 losses-from-soil; water- pollution; risk-; indexes-;
 NAL Call No.:  S539.5.J68
 28. Cyclic and blending strategies for using nonsaline and saline 
 waters for irrigation.
 Bradford, S.; Letey, J. 
 Irrig-sci. Berlin, W. Ger. : Springer International. 1992. v. 13
 (3) .
 Includes references.
 Descriptors: medicago-sativa; zea-mays; gossypium-hirsutum;
 rotations-; continuous-cropping; salt-tolerance; irrigation-;
 blending-; cycling-; irrigation-water; saline-water; salinity-;
 water-quality; simulation- models; dry-matter-accumulation;
 electrical-conductivity; mathematical- models
 Abstract: Large quantities of saline water frequently exist in
 irrigated  areas of the world. Various strategies have been
 proposed to use these  saline waters. Blending involves mixing
 saline water with good quality  water to an acceptable salinity
 and then using this water to irrigate  crops. The cyclic strategy
 uses waters of various salinities separately  either during one
 season or in a crop rotation as a function of the  crop's salt
 tolerance. A multi-seasonal transient state model, known as  the
 modified van Genuchten-Hanks model, was used to investigate the 
 effects of cyclic or blending application of irrigation waters of
 two  salinity levels on alfalfa (Medicago sativa L.), and on a
 corn (Zea  mays L.) and cotton (Gossypium hirsutum L.) crop
 rotation. Simulated  alfalfa yields were similar for the cyclic
 and blending strategies that  applied the same amount of salt and
 water. The cyclic strategy produced  higher simulated yields of
 salt-sensitive corn than the blending  strategy, whereas the
 simulated salt-tolerant cotton yield was not  affected by the two
 strategies. The beneficial effects of the cyclic  strategy on
 corn production decreased under deficit irrigation.
 NAL Call No.:  S612.I756
 29. Dairy manure and plant nutrient management issues affecting
 water  quality and the dairy industry.
 Lanyon, L. E. 
 J-dairy-sci v.77, p.1999-2007. (1994).
 Includes references.
 Descriptors: cattle-manure; water-pollution; pollution-control;
 dairy-farms; cattle-feeding; production-costs;
 environmental-policy; usa-
 Abstract: Specific requirements for dairy manure management to
 protect water  quality from nutrient pollution depend on the
 organization of  individual farms. Further, the management
 requirements and options are  different for point (farmstead) and
 nonpoint (field-applied) sources of  pollution from farms. A
 formal management process can guide decisions  about existing
 crop nutrient utilization potential, provide a framework  for
 tracking nutrients supplied to crops, and identify future 
 requirements for dairy manure management to protect water
 quality. Farm  managers can use the process to plan daily
 activities, to assess annual  nutrient management performance,
 and to chart future requirements as  herd size increases.
 Agronomic measures of nutrient balance and  tracking of inputs
 and outputs for various farm management units can  provide the
 quantitative basis for management to allocate better manure  to
 fields, to modify dairy rations, or to develop alternatives to
 on- farm manure application. Changes in agricultural production
 since World  War II have contributed to a shift from land-based
 dairy production to  a reliance on capital factors of production
 supplied by the dairy  industry. Meanwhile, management of dairy
 manure to meet increasingly  stringent water quality protection
 requirements is still a land-based  activity. Involving the dairy
 industry and off-farm stakeholders as  participants in the
 management process for field, farm, and regional  dairy
 production can be the basis for decision-making to reconcile the 
 sometimes conflicting demands of production and water quality 
 NAL Call No.:  44.8-J822
 30. Design of forest riparian buffer strips for the protection of
 water  quality : analysis of scientific literature.  Analysis of
 scientific literature.
 Belt, G. H.;  O'Laughlin, J.;  Merrill, T.; Idaho Forest, W. a.
 R. P. A. G. 
 Moscow, ID : Idaho Forest, Wildlife and Range Policy Analysis 
 Group, [1992] iv, 35 p..
 "June 1992.".
 Descriptors: Riparian-ecology-Idaho; Riparian-forests-Idaho;
 Fishes-Idaho-Effect- of-logging-on;
 NAL Call No.:  QH541.5.R52B44--1992
 31. Desing, installation, and performance of percolation
 lysimeters for  water quality sampling.
 Klocke, N. L.; Todd, R. W.; Hergert, G. W.; Watts, D. G.;
 Parkhurst, A. M. 
 Trans-A-S-A-E v.36, p.429-435. (1993).
 Literature review.
 Descriptors: irrigation-; leachates-; lysimeters-; percolation-;
 water-quality; zea-mays; literature-reviews; nebraska-
 Abstract: Lysimeters are the primary research tool for measuring
 percolation  and water quality. Monolithic percolation lysimeters
 were evaluated for  measuring the quantity and quality of
 leachate from the root zone of  irrigated crops. Six percolation
 lysimeters were installed in a  continuous corn (Zea mays L.)
 cropping system near North Platte,  Nebraska, during the fall of
 1988 and spring 1989. The lysimeters were  0.9 m in diameter and
 2.4 m deep. They were filled with undisturbed  soil using a
 hydraulic pull-down method. Porous stainless steel  extractors
 were installed vertically upward into the lysimeter bottoms,  and
 leachate was extracted from the unsaturated soil. Leachate
 volume,  volumetric soil water content, soil temperature, and
 soil bulk density  were measured. Isolation of a large soil
 monolith in the lysimeter did  not significantly affect plant
 growth, soil bulk density, or  temperature. Soil water content
 near the lysimeter bottoms was greater  than in the surrounding
 field after a wet spring in 1991. However,  extractors removed
 most excess water and adequately matched unsaturated  drainage in
 the field. Though leachate varied among lysimeters, they  behaved
 similarly over time. Results will help relate irrigation 
 management and scheduling strategies to potential leaching of
 soil  water and associated chemicals into groundwater.
 NAL Call No.:  290.9-AM32T
 32. Development and implementation of the Virginia agronomic land
 use  evaluation system (values).
 Donohue, S. J.; Simpson, T. W.; Baker, J. C.; Monnett, M. M.;
 Hawkins, G. W. 
 Commun-soil-sci-plant-anal. New York, N.Y. : Marcel Dekker. 1994. 
 v. 25 (7/8) p. 1103-1108. 
 Paper presented at the 1993 International Symposium on Soil
 Testing  and Plant Analysis: Precision Nutrient Management,
 August 14-19, 1993,  Olympia, Washington. Part 1.
 Descriptors: fertilizer-requirement-determination; soil-testing;
 nutrients-; management-; databases-; land-use; land-evaluation;
 water-quality; environmental-protection; water-pollution;
 pollution-control; point- sources; virginia-;
 nutrient-management; nonpoint-source-pollution; values-database
 NAL Call No.:  S590.C63
 33. Dynamic simulation modelling for evaluating water quality
 response  to agricultural BMP implementation.
 Cassell, E. A.; Clausen, J. C. 
 Water-sci-technol v.28, p.635-648. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: agricultural-land; phosphorus-;
 input-output-analysis; movement-in- soil; groundwater-pollution;
 surface-water; pollution-; sources-; dynamic-models;
 simulation-models; vermont-; best-management-practices
 NAL Call No.:  TD420.A1P7
 34. An economic analysis of cover crop use in Georgia to protect 
 groundwater quality.
 Jordan, J. L.; Morgan, S. L.; Elnagheeb, A. H. 
 Res-bull-Univ-Ga,-Coll-Agric,-Exp-Stn. Athens, Ga. : The
 Stations,  1967-. June 1994. (419) 13 p. 
 Includes references.
 Descriptors: cover-crops; leaching-; groundwater-; nitrates-;
 nitrogen-; fertilizers-; cost-benefit-analysis; secale-cereale;
 NAL Call No.:  S51.E2
 35. Economic and environmental considerations for nitrogen
 management  in the mid-Atlantic coastal plain.
 Norris, P. E.; Shabman, L. A. 
 Am-J-Alternative-Agric v.7, p.148-156. (1992).
 Includes references.
 Descriptors: crop-production; nitrogen-; organic-fertilizers;
 rotations-; poultry-manure; cost-benefit-analysis; water-quality;
 Abstract: A case study in eastern Virginia provides evidence that
 both  environmental and farm profit goals may be satisfied by
 alternative  nitrogen (N) management strategies for grain
 production. We used a  linear programming framework with an N
 mass balance model to calculate  returns from several options for
 providing N to crops. Replacing single  applications of inorganic
 N fertilizer with split applications or with  additions of
 organic N were found to reduce the potential for N loss  from
 cropland and to increase net returns. For some N management 
 strategies, however, adaption may require financial and
 educational  assistance. As a result, water quality policies may
 benefit by  including such incentives.
 NAL Call No.:  S605.5.A43
 36. Economic and environmental effects of nitrogen testing for 
 fertilizer management.
 Bosch, D. J.;  Fuglie, K. O.;  Keim, R. W.; United States. Dept.
 of Agriculture. Economic Research Service. Resources and
 Technology Division. 
 [Washington, D.C.] : Economic Research Service, Resources and 
 Technology Division, [1994] iv, 37 p. : ill., map.
 Cover title.
 Descriptors: Nitrogen-fertilizers-United-States;
 NAL Call No.:  aS651.B67--1994
 37. Effect of conventional vs. no-tillage on pesticide leaching
 to  shallow groundwater.
 Isensee, A. R.; Nash, R. G.; Helling, C. S. 
 J-Environ-Qual v.19, p.434-440. (1990).
 Includes references.
 Descriptors: atrazine-; metabolites-; alachlor-; cyanazine-;
 carbofuran-; leaching-; groundwater-pollution; no-tillage-;
 tillage-; zea-mays; maryland-; deethylatrazine-
 Abstract: A field site was established at Beltsville, MD, in 1986
 to assess  the effect of conventional and no-till cultural
 practices on the  movement of pesticides into shallow
 groundwater. Groundwater samples  taken from unconfined (< 1.5 m
 deep) and confined (< 3 m deep)  monitoring wells in 1986-1988
 were analyzed for atrazine [6-chloro-N-
 deethylatrazine  [6-chloro-N-(1-methylethyl)-1,
 3,5-triazine-2,4-diamine], alachlor 12- chloro-N-2,
 6-diethylphenyl)-N-(methoxymethyl)acetamide], cyanazine [2-
 [[4-chloro-6-(ethylamino)-1,3,5-triazine-2-yl] amino]-2-
 methylpropanenitrile], and carbofuran
 (2,3-dihydro-2,2-dimethyl-7- benzofuranyl methylcarbamate).
 Atrazine was found in groundwater all  year, while cyanazine,
 alachlor, and carbofuran were present only for a  short period (<
 3 mo) after pesticide application. Fairly constant  background
 levels of < 0.5 microgram L-1 atrazine were found under  fields
 treated before 1986, while levels under continuously treated 
 fields were < 2.0 microgram L-1 for 22 of 25 samplings. Pesticide 
 residues in unconfined groundwater were usually higher (ca. 2 to
 4X)  than in confined groundwater. Rainfall timing relative to
 pesticide  application was critically important to pesticide
 leaching. A prolonged  rain immediately after the 1988
 application resulted in peak atrazine  and cyanazine levels of
 ca. 200 microgram L-1 in unconfined and ca. 30  to 40 microgram
 L-1 in confined groundwater, which resulted in short- term levels
 ca. 2 to 50X greater under no-till than conventional till  plots.
 Results of this study suggest that preferential transport 
 NAL Call No.:  QH540.J6
 38. The effect of crop rotation on nitrate leaching losses;
 sandland  and limestone aquifers.
 Shepherd, M. A.; Johnson, P. A.; Smith, P. 
 Asp-appl-biol p.183-190. (1992).
 In the series analytic: Nitrate and farming systems / edited by 
 J.R. Archer, K.W.T. Goulding, S.C. Jarvis, C.M. Knott, I. Lord,
 S.E.  Ogilvy, J. Orson, K.A. Smith, and B. Wilson.
 Descriptors: nitrate-; leaching-; rotations-; crop-husbandry;
 soil-fertility; cultivation-; cover-crops; aquifers-; limestone-;
 limestone-soils; sandy-soils; cropping-systems;
 stubble-cultivation; eastern-england
 NAL Call No.:  QH301.A76
 39. Effect of extractable soil surface phosphorus on runoff water 
 Daniel, T. C.; Edwards, D. R.; Sharpley, A. N. 
 Trans-ASAE v.36, p.1079-1085. (1993).
 Includes references.
 Descriptors: losses-from-soil; phosphorus-; pollution-; runoff-;
 water-quality; arkansas-
 Abstract: Phosphorus (P) additions to surface water from
 agricultural  nonpoint sources are of concern, because P often
 limits eutrophication  of surface waters. Numerous sources of
 runoff P exist: indigenous soil  and plant material, land-applied
 manure and sludge, and commercial  fertilizer. In many soils
 receiving commercial fertilizer and manure,  concentrations of P
 at the soil surface have been steadily rising due  to either
 long-term or excessive applications of P. Critical levels of 
 soil surface P may exist, above which runoff may promote 
 eutrophication. Methods for rationally identifying these critical 
 levels are needed to manage losses of P, which implies the need
 for  curate methods of relating soil surface P concentration (Ps)
 to runoff  P concentration. A study was conducted on both pasture
 and tilled plots  (with and without residue) to evaluate the
 relationship between Ps and  dissolved reactive P in runoff (PR)
 using simulated rainfall. The data  indicated that even for
 comparable storms, Ps alone was not a  satisfactory estimator of
 PR. A model describing the kinetics of P  release from surface
 soil to runoff was used to include additional  variables in
 predicting PR. When used with uncalibrated parameters, the  model
 explained a significant proportion of the variation in observed 
 PR values for pasture plots (r2 = 0.43) but was less successful
 in  predicting PR for tilled plots (with and without residue, r2
 = 0.13).  Calibration of (adjustments to) the extraction
 coefficients resulted in  an overall coefficient of determination
 between observed and predicted  PR values of 0.73. While the
 model was successful in describing how PR  and the independent
 variables are related for the pasture plots, the  extraction
 coefficients should be calibrated to obtain best estimates  of
 PR. When used with calibrated extraction coefficients, the model 
 NAL Call No.:  290.9-Am32T
 40. Effect of soil test phosphorus on runoff water quality.
 Daniel, T. C.; Edwards, D. R.; Sharpley, A. N. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1991. (91-2605) 13 p. 
 Paper presented at the 1991 International Winter Meeting
 sponsored  by The American Society of Agricultural Engineers,
 December 17-20,  1991, Chicago, Illinois.
 Descriptors: soil-; water-quality; phosphorus-; water-pollution;
 NAL Call No.:  290.9-Am32P
 41. Effect of tillage systems on soil erosion and runoff water
 Seta, A. K. 1. 
 1991. vii, 68 leaves : ill..
 Includes vita and abstract.
 Descriptors: Soil-erosion; Runoff-; Tillage-
 NAL Call No.: KyU Thesis-1991-Seta
 42. Effectiveness of BMPs for stormwater management in urbanized 
 Kuo, C. Y.; Virginia Water Resources Research Center. 
 Blacksburg : Virginia Water Resources Research Center, Virginia 
 Polytechnic Institute and State University, 1987. xiii, 121 p. :
 ill.,  maps.
 Partly funded by the U.S. Geological Survey, U.S. Dept. of the 
 Descriptors: Urban-runoff-Mathematical-models;
 Water-quality-management-Data- processing
 NAL Call No.:  TD201.V57--no.159
 43. The effectiveness of buffer strips for ameliorating offsite 
 transport of sediment, nutrients, and pesticides from
 silvicultural  operations.
 Comerford, N.;  Mansell, R.;  Neary, D.; National Council of the
 Paper Industry for Air and Stream Improvement (U.S.). 
 New York, N.Y. : National Council of the Paper Industry for Air
 and  Stream Improvement, 1992. ii, 48 p. ; 28 cm..
 "June 1992.".
 Descriptors: Forest-management-Environmental-aspects;
 Forest-influences; Water- Pollution,
 NAL Call No.:  TD899.P3N34-no.631
 44. Effectiveness of vegetative buffer strips in reducing
 herbicide  transport with surface runoff under simulated
 Misra, A. K.; Baker, J. L.; Mickelson, S. K.; Shang, H. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Summer 1994. (94-2120/94-2155) 21 p. 
 Paper presented at the 1994 International Summer Meeting,
 sponsored  by the ASAE, June 19-22, 1994, Kansas City, Missouri.
 Descriptors: grass-strips; water-pollution; water-quality;
 runoff-water; herbicides-; rainfall-simulators
 NAL Call No.:  290.9-Am32P
 45. Effects of agricultural nutrient management on nitrogen fate
 and  transport in Lancaster County, Pennsylvania.
 Hall, D. W.; Risser, D. W. 
 Water-resour-bull v.29, p.55-76. (1993).
 Includes references.
 Descriptors: nitrogen-; nitrates-; application-to-land;
 movement-in-soil; losses- from-soil; water-budget;
 precipitation-; groundwater-; manures-; fertilizers-; hydrology-;
 groundwater-pollution; pennsylvania-; best-management-practices;
 nonpoint-source-pollution; groundwater- hydrology
 Abstract: Nitrogen inputs to, and outputs from, a 55-acre site in
 Lancaster  County, Pennsylvania, were estimated to determine the
 pathways and  relative magnitude of loads of nitrogen entering
 and leaving the site,  and to compare the loads of nitrogen
 before and after the  implementation of nutrient management.
 Inputs of nitrogen to the site  were manure fertilizer,
 commercial fertilizer, nitrogen in  precipitation, and nitrogen
 in ground-water inflow; and these sources  averaged 93, 4, 2, and
 1 percent of average annual nitrogen additions,  respectively.
 Outputs of nitrogen from the site were nitrogen in  harvested
 crops, loads of nitrogen in surface runoff, volatilization of 
 nitrogen, and loads of nitrogen in ground-water discharge, which 
 averaged 37, less than 1, 25, and 38 percent of average annual
 nitrogen  removals from the site, respectively. Virtually all of
 the nitrogen  leaving the site that was not removed in harvested
 crops or by  volatilization was discharged in the ground water.
 Applications of  manure and fertilizer nitrogen to 47.5 acres of
 cropped fields  decreased about 33 percent, from an average of
 22,700 pounds per year  (480 pounds per acre per year) before
 nutrient management to 15,175  pounds of nitrogen per year (320
 pounds per acre per year) after the  implementation of nutrient
 management practices. Nitrogen loads in  ground-water discharged
 from the site decreased about 30 percent, from  an average of 292
 pounds of nitrogen per million gallons of ground  water before
 nutrient management to an average of 203 pounds of  nitrogen per
 million gallons as a result of the decreased manure and 
 commercial fertilizer applications. Reductions in manure and
 commercial  fertilizer applications caused a reduction of
 approximately 11,000  pounds (3,760 pounds per year; 70. ground
 water from the 55-acre site during the three-year period 1987-
 NAL Call No.:  292.9-Am34
 46. Effects of deep tillage on redistribution of lead shot and
 chufa  tuber biomass at Catahoula Lake, Louisiana.
 Peters, M. S. M. S. 1. 
 1992. vi, 25 leaves : ill..
 Descriptors: Waterfowl-management-Louisiana;
 Lead-Toxicology-Louisiana; Tillage- Louisiana; Catahoula-Lake-La
 NAL Call No.: LU 378.76-L930-1992-pete
 47. Effects of management practices on surface water quality from
 rice  fields.
 Feagley, S. E.; Sigua, G. C.; Bengston, R. L.; Bollich, P. K.;
 Linscombe, S. D. 
 La-Agric-La-Agric-Exp-Stn v.36, p.8-10. (1993).
 Descriptors: oryza-sativa; water-pollution; weed-control;
 cultural-control; fertilizers-; field-tests; no-tillage-;
 cultivation-; water-quality; louisiana-
 NAL Call No.:  100-L939
 48. Effects of poultry litter application on surface water
 quality. 1.  A field experiment.
 Huhnke, R. L.; Storm, D. E.; Brown, G. O.; Smolen, M. D. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Summer 1992. (92-2121/92-3010) 14 p. 
 Paper presented at the "1992 International Summer Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 June 21-24, 1992,  Charlotte, North Carolina.
 Descriptors: poultry-manure; soil-chemistry; pastures-;
 runoff-water; tillage-; plant-height; water-quality;
 water-pollution; waste-utilization; rain-; oklahoma-
 NAL Call No.:  290.9-Am32P
 49. The effects of tillage and crop residues on water and nitrate 
 movement in soil columns.
 Serem, V. K.; Madramootoo, C. A. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Summer 1993. (932082) 16 p. 
 Paper presented at the "1993 International Summer Meeting
 sponsored  by The American Society of Agricultural Engineers, and
 The Canadian  Society of Agricultural Engineering," June 20-23,
 1993, Spokane,  Washington.
 Descriptors: tillage-; crop-residues; nitrates-; water-quality;
 drainage-; leaching-
 NAL Call No.:  290.9-Am32P
 50. Effects of tillage on pesticide concentrations in shallow
 ground  water and surface runoff from fragipan soils in North
 Mississippi, USA.
 Smith, S. Jr. 
 Proceedings of Industrial and Agricultural Impacts on the 
 Hydrologic Environment  the Second USA/CIS Joint Conference on 
 Environmental Hydrology and Hydrogeology / USA/CIS Joint
 Conference on  Environmental Hydrology and Hydrogeology.
 Alexandria, VA : Water  Environment Federation, c1993.. v. 2 p.
 Title on cover : Environmental impact of agricultural practices
 and  agrichemicals / edited by Y. Eckstein and A. Zaporozec.
 Descriptors: glycine-max; groundwater-pollution; surface-water;
 runoff-; pesticides-; concentration-; watersheds-; fragipans-;
 no-tillage-; movement-in-soil; mississippi-
 NAL Call No.:  GB652.U82-1993
 51. Estimation of nitrate concentrations in groundwater using a
 whole  farm nitrogen budget.
 Barry, D. A. J.; Goorahoo, D.; Goss, M. J. 
 J-environ-qual v.22, p.767-775. (1993).
 Includes references.
 Descriptors: nitrate-nitrogen; leaching-; nitrogen-balance;
 farming-systems; rotations-; zea-mays; glycine-max;
 triticum-aestivum; phleum-pratense; medicago-sativa;
 groundwater-pollution; farming-systems-research; ontario-
 Abstract: Contamination of groundwater under agricultural land by
 NO3 is  influenced by the kind of farming   system. One possible
 method of  selecting farming systems that result in less NO3
 leaching is to    calculate whole farm N budgets, that are
 simplified by assuming soil-N  remains constant from one   cycle
 of a rotation to the next. This  method was applied to two model
 crop rotations using   average crop  yield data for two regions
 of Ontario, and to a cash-crop farm and a  dairy farm using  
 information on purchases, sales, and crop yields,  for these
 farms. The model rotations were corn   (Zea mays L.)-soybean 
 [Glycine max (L.) Merr.]-wheat (Triticum aestivum L.) and 
 corn-soybean- wheat-hay (mixture of timothy, Phleum pratense L.
 and alfalfa, Medicago  sativa   L.)-hay-hay. Atmospheric
 deposition (18.4 kg N ha-1 yr) was  obtained by literature
 review.   Symbiotic N2 fixation by legume crops  with different
 yields was estimated from regression  equations. A net  surplus
 in the N balance was converted to maximum mean NO3-N 
 concentration in   groundwater by assuming a groundwater recharge
 rate  of 160 mm yr-1, and no denitrification.   Predicted NO3-N 
 concentrations in leachate for the model corn-soybean-wheat
 rotation  were greater   for southwestern Ontario (22.4 mg L-1)
 than western  Ontario (8.5 mg L-1), probably because more N  
 fertilizer was  recommended in the southwest. Including hay in
 the model rotation  increased the   amount of N leached by a
 factor of two in western  Ontario, but only by 9% in the
 southwest. was 6.7 mg L-1, compared with  an average measured
 value of 9.5 mg L-1  in the tile drainage water. For the dairy
 farm the   predicted value  was 58 mg L-1 and a measured value
 was not available. The simplified N  balance   method provided
 useful estimates of potential NO3 leaching  losses even though it
 relied on some   major assumptions. A major  uncertainty was
 atmospheric deposition of ammonia volatilized from   on- farm
 sources. Denitrification could be as much as 62 kg N ha-1 yr-1 
 undr continuous  production of grain corn, based on differences 
 between N present after harvest and amount of N   leached.
 NAL Call No.:  QH540.J6
 52. Evaluating farming strategies for water quality at the Ohio 
 Management Systems Evaluation Area.
 Watermeier, N. L.; Workman, S. R.; Nokes, S. E.; Borwn, L. C. 
 Proceedings of the National Symposium on Protecting Rural
 America's  Water Resources  Partnerships for Pollution Solutions,
 October 23-26,  1994, Omni Shoreham Hotel, Washington, DC /
 National Symposium on  Protecting Rural America's Water
 Resources: Partnerships for Pollution  Solutions. [Oklahoma,
 City, OK? : Ground Water Protection Council?,  1994]. p. 185-195. 
 Includes references.
 Descriptors: zea-mays; glycine-max; triticum-aestivum;
 continuous-cropping; rotations-; no-tillage-; tillage-;
 cover-crops; vicia-villosa; nitrate- ; alachlor-; metribuzin-;
 chlorimuron-; leaching-; groundwater- pollution; water-quality;
 crop-yield; atrazine-; ohio-; ridge-tillage
 NAL Call No.:  TD927.N38-1994
 53. Evaluating herbicide removal by buffer strips under natural 
 Arora, K.; Mickelson, S. K.; Baker, J. L.; Tierney, D. P. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1993. (932593) 16 p. 
 Paper presented at the "1993 International Winter Meeting of the 
 American Society of Agricultural Engineers," December 14-17,
 1993,  Chicago, Illinois.
 Descriptors: herbicide-residues; water-quality; erosion-control
 NAL Call No.:  290.9-Am32P
 54. Evaluating the effectiveness of forestry best management
 practices  in meeting water quality goals or standards.
 Dissmeyer, G. E.; United States. Forest Service. Southern Region. 
 Atlanta, Ga. : USDA, Forest Service, Southern Region, [1994]
 viii,  166 p. : ill..
 "July 1994.".
 Descriptors: Water-quality-United-States;
 NAL Call No.:  1--Ag84M-no.1520
 55. Evaluation of a rice herbicide transport model.
 Breuer, R. S.; California Environmental Protection Agency.
 Environmental Hazards Assessment Program. 
 Sacramento, Calif. : Environmental Hazards Assessment Program, 
 State of California, Environmental Protection Agency, Dept. of 
 Pesticide Regulation, Environmental Monitoring and Pest
 Management  Branch, [1992] iv, 7 p. : ill..
 Cover title.
 Water- Pollution-California-Sacramento-River-Computer-programs
 NAL Call No.:  TD427.P35B74--1992
 56. An evaluation of extension programs to enhance water quality 
 through nutrient management in the urban landscape.
 Relf, P. D.; McKissack, D. 
 HortTechnology v.2, p.245-247. (1992).
 Includes references.
 Descriptors: cooperative-extension-service; volunteers-;
 environmental- education; educational-programs; water-quality;
 water-pollution; fertilizers-; runoff-; mass-media;
 extension-education; technology- transfer; maryland-;
 nonpoint-source-pollution; chesapeake-bay; master-gardeners
 NAL Call No.:  SB317.5.H68
 57. Evaluation of GLEAMS and PRZM for predicting pesticide
 leaching  under field conditions.
 Zacharias, S.; Heatwole, C. D. 
 Trans-ASAE v.37, p.439-451. (1994).
 Includes references.
 Descriptors: zea-mays; no-tillage-; pesticides-; leaching-;
 simulation-models; virginia-; groundwater-loading;
 pesticide-rootzone-model; nonpoint-source-pollution
 Abstract: Pesticide simulation models, GLEAMS and PRZM, were
 evaluated for  their ability to predict pesticide behavior using
 field data from a  plot under no-till corn in the Coastal Plain
 region of Virginia. The  models were evaluated in an uncalibrated
 mode as well as with  adjustment of important hydrology
 parameters. The evaluation of model  performance was based on
 graphical displays and statistical measures.  Difference in
 evapotranspiration (ET) predictions by the two models  caused the
 simulated results from their hydrology components to vary. 
 Runoff and soil moisture measured in the field were predicted 
 reasonably well after adjusting important hydrology parameters.
 Except  for differences in magnitude, both models predicted the
 chemical  concentration profiles similarly. Overall, GLEAMS
 represented pesticide  behavior in soil better than PRZM. The
 models, GLEAMS and PRZM,  performed well in predicting pesticide
 mass in the root zone, but were  less reliable in predicting
 pesticide concentration distributions in  soil. Model predictions
 of pesticide fate and transport were not  greatly affected by
 changes in curve number and the water holding  capacity of the
 NAL Call No.:  290.9-Am32T
 58. Evaluation of two field screening test kits for the detection
 of  PCBs in soil by immunoassay.
 Waters, L. C.; Smith, R. R.; Stewart, J. H.; Jenkins, R. A.;
 Counts, R. W. 
 J-AOAC-Int v.77, p.1664-1671. (1994).
 Includes references.
 Descriptors: soil-testing; polluted-soils;
 polychlorinated-biphenyls; contamination-; determination-;
 screening-; immunoassay-
 NAL Call No.:  S583.A7
 59. Fall tillage method: effect on short-term carbon dioxide flux
 from  soil.
 Reicosky, D. C.; Lindstrom, M. J. 
 Agron-j v.85, p.1237-1248. (1993).
 Includes references.
 Descriptors: autumn-; tillage-; techniques-; no-tillage-;
 carbon-dioxide; flow-; soil-air; global-warming;
 greenhouse-effect; air-pollution; climatic- change;
 soil-analysis; organic-compounds; carbon-; soil-water-content;
 soil-; surface-roughness; surface-roughness; minnesota-
 Abstract: The increasing concern for rising CO2 concentrations
 from  agricultural activities has prompted the   need to better
 understand  the flux of greenhouse gases to the atmosphere.  This
 work determines    the effect of four fall tillage methods on
 short-term CO2 flux from a  Hamerly clay loam   (fine-loamy,
 frigid Aeric Calciaquoll) in the  northern Corn Belt. Moldboard
 plow only, moldboard   plow plus disk  harrow twice, disk harrow
 once, and chisel plow once using standard  tillage  equipment
 following a wheat (Triticum aestivum L.) crop were  compared with
 no-tillage.  The CO2   flux was measured with a large  portable
 system commonly used to measure canopy gas exchange of  field 
 crops.  Measurements of CO2 flux were initiated within 5 min
 after  tillage completion for   each tillage treatment and
 continued  intermittently for 19 d. Moldboard plow had the
 roughest soil   surface  and the highest initial CO2 flux (29 g
 m-2 h-1) and maintained the  highest flux throughout   the study. 
 Moldboard plow plus disking twice  and chisel plow had similar
 initial rates (7 and 6 g   m-2 h-1,  respectively) that were
 greater than disk harrow and no-tillage.  The  high initial CO2  
 fluxes were more related to depth of soil  disturbance that
 resulted in a rougher surface and   larger voids than  to residue
 incorporation. The differences in CO2 flux between tillage   
 treatments were small but consistent 19 d after initial tillage
 and 64  mm rain. Lower CO2 flux  rates caused by tillage were
 associated with  low soil disturbance and/or small voids. 
 Tillage. soil management can   minimize agriculture's impact on
 global CO2  increase.
 NAL Call No.:  4-AM34P
 60. Farm nutrient management training needs assessment for
 Minnesota :  a nutrient management technical assistance project.
 Minnesota. Dept. of Agriculture. 
 [Saint Paul, Minn. : Minnesota Dept. of Agriculture, 1994] 61 p.
 :  1 map.
 "Funded by a grant from USEPA, Section 319 of the Water Quality
 Act  of 1987, "Nonpoint source management".".
 Descriptors: Soil-management-Minnesota; Soil-fertility-Minnesota;
 Soil-science- Minnesota; Needs-assessment-Minnesota
 NAL Call No.:  S599.M6F37--1994
 61. A farm scale water quality planning system for evaluating
 best  management practices.
 Batchelor, W. D.; Dillaha, T. A. I.; Wolfe, M. L.; Heatwole, C.
 D.; Mostaghimi, S. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Summer 1994. (94-2156/94-2185) 17 p. 
 Paper presented at the "1994 International Summer Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 June 19-22, 1994,  Kansas City, Missouri.
 Descriptors: water-pollution; water-quality; land-management;
 simulation-models; pollution-control; non-point-source-pollution
 NAL Call No.:  290.9-Am32P
 62. A field study to evaluate leaching of aldicarb, metolachlor,
 and  bromide in a sandy loam soil.
 Smith, C. N.; Parrish, R. S. 
 J-environ-qual v.22, p.562-577. (1993).
 Paper presented at the USDA-ARS Beltsville Agricultural Research 
 Center Symposium XVII, "Agricultural Water Quality Priorities, A
 Team  Approach to Conserving Natural Resources," May 4-8, 1992,
 Beltsville,  MD.
 Descriptors: aldicarb-; granules-; metolachlor-;
 emulsifiable-concentrates; bromide-; tracers-; leaching-;
 vertical-movement; application-; spatial- variation; soil-depth;
 sandy-loam-soils; saturated-conditions; persistence-; half-life;
 arachis-hypogaea; uptake-; georgia-
 Abstract: Transport and transformation of pesticides used in
 agricultural  situations are subject to vailability from several
 sources that are  impossible to simulate in laboratory settings.
 This study was conducted  to characterize pesticide leaching
 behavior under conventional croping  conditions and to determine
 the impacts of related sources of  vailability. An agricultural
 field site (Ardilia fine sandy loam,  Clarendon loamy sand,
 Tifton loamy sand, and Lucy loamy sand) located  within the
 Dougherty Plain region of southwest Georgia was used to  study
 pesticide movement in unsaturated and saturated soil zones from 
 1984 through 1988. A granular formulation of aldicarb [2-methyl-2
 -  (methylthio) propionaldehyde O-(methylcarbamoyl) oxime], an 
 emulsifiable concentrate of metolachlor
 [2-chloro-N-(2-ethyl-6-methyl- phenyl)-N-(2-metboxy-1-methyl
 ethyl) acetamide], and a bromide (Br-)  tracer were applied on
 peanut (Arachis hypogea L.) crops under modified  conventional
 tillage practices. Postapplication vertical movement was 
 monitored for periods of up to 111 d for pesticides and 1307 d
 for Br-.  Application distributions for aldicarb showed measured
 coefficients of  variation ranging from 42 to 72, and for
 metolachlor from 23 to 44.  Spatial variability analyses
 indicated the existence of small-scale  correlation for both
 pesticides upon initial application, and some  large-scale
 trending was observed for metolachlor. Field-based 
 transformation rates of aldicarb were up to three times higher
 than  laboratory-based values. There was no evidence of migration
 of any of  the pesticides into the saturated zone during the
 study, although Br-  was observed at less than 1 mg kg(-1) in
 well-water samples. Aldicarb  degraded almost completely within d
 each year, and. concentrations decreasing with increasing depth,
 and there was no  significant movement below 0.3 m. Bromide was
 observed in soil samples  as deep as 3 m only on the 1307th d,
 and the profiles showed peak  concentrations no lower than 1.5 m
 with relative verticaldispersion  increasing continuously.
 NAL Call No.:  QH540.J6
 63. Forest practices as nonpoint sources of pollution in North
 Binkley, D.; Brown, T. C. 
 Water-resour-bull v.29, p.729-740. (1993).
 Includes references.
 Descriptors: water-pollution; streams-; water-quality;
 forest-influences; forest- management; usa-; canada-
 Abstract: Forest management activities may substantially alter
 the quality of  water draining forests, and are   regulated as
 nonpoint sources of  pollution. Important impacts have been
 documented, in some cases,   for  undesirable changes in stream
 temperature and concentrations of  dissolved oxygen, nitrate-N, 
 and suspended sediments. We present a  comprehensive summary of
 North American studies that have   examined  the impacts of
 forest practices on each of these parameters of water  quality.
 In most   cases, retention of forested buffer strips along 
 streams prevents unacceptable increases in stream   temperatures. 
 Current practices do not typically involve addition of large
 quantities  of fine   organic material to streams, and depletion
 of streamwater  oxygen is not a problem; however,  sedimentation
 of gravel streambeds  may reduce oxygen diffusion into spawning
 beds in some cases.   Concentrations of nitrate-N typically
 increase substantially after  forest harvesting and  
 fertilization, but only a few cases have  resulted in
 concentrations approaching the drinking-water   standard of  10
 mg of nitrate- N/L. Road construction and harvesting increase 
 suspended sediment concentrations in streamwater, with highly 
 variable results among regions in North America. The use of best 
 management practices usually prevents unacceptable increases in 
 sediment  concentrations, but exceptionally large responses
 (especially  in relation to intense storms) are not unusual.
 NAL Call No.:  292.9-Am34
 64. Forests as nonpoint sources of pollution, and effectiveness
 of best  management practices.
 National Council of the Paper Industry for Air and Stream
 Improvement (U.S.). 
 New York, N.Y. : National Council of the Paper Industry for Air
 and  Stream Improvement, 1994. 2, iii, 57 p. : ill..
 Cover title.
 Descriptors: Nonpoint-source-pollution-United-States;
 Forest-management- Environmental-aspects-United-States;
 Watershed-management-Environmental- aspects-United-States
 NAL Call No.:  TD899.P3N34--no.672
 65. GLEAMS modeling of BMPs to reduce nitrate leaching in Middle 
 Suwannee River Area.
 Reck, W. R. 
 Environmentally sound agriculture  proceedings of the second 
 conference  20-22 April 1994 /. St. Joseph, Mich. : American
 Society of  Agricultural Engineers, c1994. 1994. 361-367. 
 Includes references.
 Descriptors: groundwater-; water-quality; nitrate-nitrogen;
 leaching-; farming- systems; farm-management; dairy-farming;
 poultry-farming; monitoring-; models-; computer-techniques;
 NAL Call No.:  S589.7.E57-1994
 66. GOSSYM/COMAX: a cotton crop management emphasizing irrigation 
 scheduling and water quality.
 McKinion, J. M.; Boone, M. Y. L.; Porter, D. O.; Whisler, F. D. 
 Proceedings of Industrial and Agricultural Impacts on the 
 Hydrologic Environment  the Second USA/CIS Joint Conference on 
 Environmental Hydrology and Hydrogeology / USA/CIS Joint
 Conference on  Environmental Hydrology and Hydrogeology.
 Alexandria, VA : Water  Environment Federation, c1993.. v. 2 p.
 Title on cover : Environmental impact of agricultural practices
 and  agrichemicals / edited by Y. Eckstein and A. Zaporozec.
 Descriptors: gossypium-; irrigated-farming;
 irrigation-scheduling; simulation- models; water-quality;
 NAL Call No.:  GB652.U82-1993
 67. Herbicide leaching under tilled and no-tillage fields.
 Gish, T. J.; Shirmohammadi, A.; Vyravipillai, R.; Wienhold, B. J. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  May/June 1995. v. 59 (3) p. 895-901. 
 Includes references.
 Descriptors: atrazine-; alachlor-; losses-from-soil;
 formulations-; persistence- ; adsorption-; degradation-;
 leaching-; movement-in-soil; no-tillage-; tillage-;
 drained-conditions; controlled-release; groundwater-; water-
 quality; maryland-; well-drained-soils
 Abstract: The effect of no-tillage practices on water quality
 exiting the  root zone of deep, well-drained fields is largely
 unknown. This project  was initiated to determine herbicide
 leaching characteristics as  influenced by tillage practice and
 herbicide formulation. The research  site consisted of four
 adjacent (0.25-ha) fields, two fields each  dedicated to either
 tilled or no-tillage management. One field in each  tillage
 regime received a controlled-release formulation of atrazine [6-
 chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine] and 
 starch encapsulated], while the others received standard
 herbicide  formulations of atrazine and alachlor. Both herbicide
 formulations were  annually applied at the same rate: 1.7 kg ha-1
 for atrazine and 2.8 kg  ha-1 for alachlor. Atrazine,
 deethylatrazine [DEAT; 6-chloro-N-(1-
 methylethyl)-1,3,5-triazine-2,4-diamine], alachlor, and Br-1 
 concentrations were monitored with 12 suction lysimeters (six
 each at  1.5- and 1.8-m depths) in each field. Alachlor was
 detected in <3% of  all samples collected, regardless of tillage
 practice or herbicide  formulation, while atrazine was detected
 in >41% of the samples. Under  no-tillage, atrazine was detected
 in <28% of the samples with <13%  exceeding the U.S.
 Environmental Protection Agency Health Advisor level  of 3
 micrograms L-1 atrazine. Under tilled conditions, 53% of the 
 samples contained atrazine, with 35% exceeding 3 micrograms L-1 
 atrazine. Averaged atrazine metabolite concentration of DEAT
 under no- tillage was 0.52 micrograms L-1 vs. 0.39 micrograms L-1
 for tilled  fields. Similar Br- transport between tillage
 practices and reduced  atrazine levels. well-drained soils, can
 have a positive impact on groundwater quality.
 NAL Call No.:  56.9-So3
 68. Impact of BMP's on stream and ground water quality in a USDA 
 demonstration watershed in the eastern Coastal Plain.
 Stone, K. C.; Hunt, P. G.; Novak, J. M.; Matheny, T. A. 
 Environmentally sound agriculture  proceedings of the second 
 conference  20-22 April 1994 / p.280-286. (1994).
 Includes references.
 Descriptors: water-quality; evaluation-; streams-; groundwater-;
 intensive- farming; environmental-impact; watersheds-;
 north-carolina; best-management-practices
 NAL Call No.:  S589.7.E57-1994
 69. The impact of conservation tillage on pesticide runoff into
 Fawcett, R. S.; Christensen, B. R.; Tierney, D. P. 
 J-soil-water-conserv v.49, p.126-135. (1994).
 Includes references.
 Descriptors: conservation-tillage; environmental-impact;
 pesticides-; runoff-; losses-from-soil; surface-water;
 water-pollution; reviews-
 NAL Call No.:  56.8-J822
 70. Impact of reservoir tillage on runoff quality and quantity.
 Rochester, E. W.; Hill, D. T.; Yoo, K. H. 
 Trans-ASAE v.37, p.1183-1186. (1994).
 Includes references.
 Descriptors: tillage-; puddling-; runoff-; runoff-water;
 water-quality; soil- compaction; gossypium-hirsutum;
 organic-nitrogen-compounds; phosphorus- ; nitrate-; ammonium-;
 Abstract: The effects of reservoir tillage on runoff and water
 quality were  studied under two levels of soil compaction in the
 production of  cotton. A wide frame tractive vehicle was used
 during plot  establishment and during all farm operations to
 provide the desired  soil compactions. LEPA (Low Energy Precision
 Application) irrigation  was used to apply supplemental water as
 required. Runoff quantity was  monitored with flumes and runoff
 samples were taken using Coshocton- type runoff samplers.
 Thirteen runoff events were monitored and  analyzed over a
 two-year period for the replicated, four-treatment  study.
 Reservoir tillage decreased runoff and total discharges of 
 organic nitrogen and phosphate. Differences in concentrations of
 water  quality parameters (total solids, ammonium, total kjeldahl
 nitrogen,  nitrate, phosphate, and COD) were not statistically
 significant.  Although not statistically different, total runoff
 and total discharge  of water quality parameters (except
 phosphate) were lower for the low  compacted treatments compared
 to the high compacted treatments.
 NAL Call No.:  290.9-Am32T
 71. Impact of reservoir tillage on runoff quality and quantity.
 Rochester, E. W.; Hill, D. T.; Yoo, K. H. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Summer 1993. (93-2114) 16 p. 
 Paper presented at the "1993 International Summer Meeting
 sponsored  by The American Society of Agricultural Engineers and
 The Canadian  Society of Agricultural Engineering," June 20-23,
 1993, Spokane,  Washington.
 Descriptors: cotton-; tillage-; runoff-; soil-compaction;
 NAL Call No.:  290.9-Am32P
 72. Impact of tillage on microbial activity and the fate of
 pesticides  in the upper soil.
 Levanon, D.; Meisinger, J. J.; Codling, E. E.; Starr, J. L. 
 Water-air-soil-pollut v.72, p.179-189. (1994).
 Includes references.
 Descriptors: atrazine-; metolachlor-; carbofuran-; diazinon-;
 insecticide- residues; herbicide-residues; mineralization-;
 microbial-degradation; plowing-; no-tillage-;
 biological-activity-in-soil; maryland-
 NAL Call No.:  TD172.W36
 73. Impacts of tillage system and chemical incorporation on
 surface  losses of water, soil, atrazine and alachlor.
 Watermeier, N. L. 
 1993. xiii, 197 leaves : ill..
 Thesis (M.S.)--University of Nebraska--Lincoln, 1993.
 NBU LD3656-1993-W384
 74. Influence of tillage on nitrate loss in surface runoff and
 tile  drainage.
 Drury, C. F.; McKenney, D. J.; Findlay, W. I.; Gaynor, J. D. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  May/June 1993. v. 57 (3) p. 797-802. 
 Includes references.
 Descriptors: zea-mays; poa-pratensis; conservation-tillage;
 ridging-; no-tillage- ; tillage-; plowing-; nitrate-;
 losses-from-soil; runoff-; tile- drainage; runoff-water;
 drainage-water; water-quality; crop-yield; nitrogen-;
 nutrient-uptake; water-pollution; conventional-tillage
 Abstract: A study was conducted to determine the effect of
 conservation (no- tillage and ridge tillage) and conventional
 (moldboard plow) tillage  systems on NO3(-) loss through surface
 runoff and tile drainage.  Nitrate concentrations and total
 volume of surface runoff and tile  drainage from conventional
 tillage (CT), no-tillage (NT), and ridge  tillage (RT) all
 planted in continuous corn (Zea mays L.), and Kentucky  bluegrass
 (BG, Poa pratensis L.) treatments, were measured for 3 yr,  1989
 to 1991. All corn tillage treatments received a total of 178.6 kg 
 N ha-1 annually during the growing season. The volume of water
 drained  through the tiles in the corn tillage systems always
 exceeded the  volume in surface runoff, typically by factors of 2
 to 4. Tile drainage  was greatest from the CT treatments, least
 from BG, and approximately  equal from RT and NT treatments in
 1989 and 1990. Concentrations of  NO3(-) in tile water from CT,
 RT, and NT treatments exceeded the  maximum recommended safe
 limit for drinking water (10 mg N L-1) in 79%  of the leaching
 events, with flow-weighted concentrations between 12  and 17 mg N
 L-1 in 1989 and 1990. Flow-weighted NO3(-) concentrations  were
 only 1.2 and 2.6 mg N L-1 from BG in 1989 and 1990, respectively. 
 The total NO3(-) lost in tile water in 1989 was 18, 14, 14, and 1
 kg N  ha-1 from the CT, RT, NT, and BG treatments, respectively,
 whereas in  1990 there were 29, 20, 20, and 3 kg N ha-1 lost from
 the CT, RT, NT,  and BG treatments, respectively. Nitrate losses
 in surface runoff were  lower than in tile drainage, with
 maximums of 2.6 kg N ha-1 for the RT  and NT treatments in 1989
 and 5.5 kg N ha-1 for the RT treatment in  1990. In 1989 and
 1990, both RT and NT treatments had greater yields  and N uptake
 in grain than the CT treatment. A serious drought in 1991 
 limited corn.
 NAL Call No.:  56.9-So3
 75. An innovative approach to estimate bioavailable phosphorus in 
 agricultural runoff using iron oxide-impregnated paper.
 Sharpley, A. N. 
 J-environ-qual v.22, p.597-601. (1993).
 Paper presented at the USDA-ARS Beltsville Agricultural Research 
 Center Symposium XVII, "Agricultural Water Quality Priorities, A
 Team  Approach to Conserving Natural Resources," May 4-8, 1992,
 Beltsville,  MD.
 Descriptors: runoff-water; phosphorus-; bioavailability-;
 determination-; methodology-; agriculture-
 Abstract: The transport of bioavailable phosphorus (BAP) in
 agricultural  runoff can accelerate the eutrophication of
 receiving water bodies.  Bioavailable P is comprised of dissolved
 P (DP) and bioavailable  particulate phosphorus (BPP). Although
 several algal assays and  chemical extractions have been proposed
 to estimate BAP, procedural and  theoretical limitations have
 restricted their widespread use. This  study evaluates the use of
 Fe oxide-impregnated paper strips (Fe-oxide  strips) to estimate
 the potential BAP content of runoff from 20  agricultural
 watersheds in the Southern Plains during 1988 to 1990. In  the
 proposed method, BAP and DP are determined by shaking 50 mL of 
 unfiltered or filtered runoff, respectively, with one Fe-oxide
 strip  for 16 h. Phosphorus is removed from the strip by 0.1 M
 H2SO4 and  measured, with BPP calculated as the difference
 between BAP and DP.  Growth of Selnastrum capricornutum was
 related r2 = 0.63 -0.96) to the  BPP content of runoff sediment
 in 2- to 29-d incubations. Bioavailable  PP estimated by the
 proposed strip method and more widely used NaOH  extraction,
 closely followed a 1:1 relationship. Averaged for all  runoff
 events, strip DP was 90 and 75% of DP determined by standard 
 direct methods, for watersheds with and without tillage,
 respectively.  The lower estimates of strip DP may be partially
 attributed to a  greater transport of acid-hydrolyzable organic
 and condensed DP in  runoff from no-till compared to tilled
 watersheds. Acting as a P sink,  the strip method may have a
 stronger theoretical basis than chemical  extraction in
 estimating algal-available P in agricultural runoff. In 
 addition, the simplicity of the proposed Fe-oxide strip method
 will  allow BAP estimation with limited resources and may
 facilitate  evaluation of the. receiving waters.
 NAL Call No.:  QH540.J6
 76. Integrated pest management and conservation behaviors.
 Glynn, C. J.; McDonald, D. G.; Tette, J. P. 
 J-soil-water-conserv v.50, p.25-29. (1995).
 Includes references.
 Descriptors: alternative-farming; integrated-pest-management;
 environmental- protection; farmers'-attitudes;
 environmental-impact; soil- conservation; water-conservation
 NAL Call No.:  56.8-J822
 77. Integrated soil, crop and water management system to abate 
 herbicide and nitrate contamination of the Great Lakes.
 Tan, C. S.; Drury, C. F.; Gaynor, J. D.; Welacky, T. W. 
 Water-sci-technol v.28, p.497-507. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: lakes-; water-pollution; herbicides-; nitrates-;
 zea-mays; cultivation-; techniques-; cropping-systems;
 conservation-; conservation-tillage; water-table; management-;
 NAL Call No.:  TD420.A1P7
 78. Integrating water quality modeling with ecological risk
 assessment  for nonpoint source pollution control: a conceptual
 Chen, Y. D.; McCutcheon, S. C.; Rasmussen, T. C.; Nutter, W. L.;
 Carsel, R. F. 
 Water-sci-technol v.28, p.431-440. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: water-quality; protection-; pollution-control;
 ecology-; risk-; assessment-; models-; usa-;
 NAL Call No.:  TD420.A1P7
 79. Integration of geographic information systems and a computer
 model  to evaluate impacts of agricultural runoff on water
 He, C.; Riggs, J. F.; Kang, Y. T. 
 Water-resour-bull v.29, p.891-900. (1993).
 Includes references.
 Descriptors: runoff-; river-water; water-pollution;
 water-quality; nitrogen-; phosphorus-; simulation-models;
 geographical-information-systems; michigan-;
 geographic-resource-analysis-support-system-grass; grass-
 waterworks; agricultural-nonpoint-source-pollution-model-agnps;
 cass- river; saginaw-bay; best-management-practices
 Abstract: This study integrates an Agricultural Non-Point Source
 Pollution  Model (AGNPS), the Geographic Resource Analysis
 Support System (GRASS)  (U.S. Army Corps of Engineers, 1987), and
 GRASS WATERWORKS (a  hydrologic modeling tool box being developed
 at the Michigan State  University Center for Remote Sensing) to
 evaluate the impact of  agricultural runoff on water quality in
 the Cass River, a subwatershed  of Saginaw Bay. AGNPS is used to
 estimate the amounts, origin, and  distribution of sediment,
 nitrogen (N), and phosphorus (P) in the  watershed. GRASS and
 GRASS WATERWORKS are used to generate parameters  needed for
 AGNPS from digital maps, which include soil association,  land
 use, watershed boundaries, water features, and digital elevation. 
 Outputs of the model include spatially distributed estimates of
 volume  and peak runoff, overland and channel erosion, sediment
 yields, and  concentrations of nitrogen and phosphorus.
 Management scenarios are  explored in the AGNPS model to minimize
 sedimentation and nutrient  loading. Scenarios evaluated include
 variations in crop cover, tillage  methods, and other
 agricultural management practices. In addition,  areas vulnerable
 to erosion are identified for best management  practices.
 NAL Call No.:  292.9-Am34
 80. Laws and programs for controlling nonpoint source pollution
 in  forest areas.
 Brown, T. C.; Brown, D.; Binkley, D. 
 Water-resour-bull v.29, p.1-13. (1993).
 Includes references.
 Descriptors: water-pollution; water-quality; pollution-control;
 monitoring- legislation-; programs-; state-government;
 federal-government; usa-; best-management-practices
 Abstract: Recent federal legislation strengthened nonpoint source
 pollution  regulations and helped to support and standardize
 pollution control  efforts. A comprehensive review of current
 state and federal programs  for forest areas reveals a
 substantial increase in agency water quality  protection
 activities. These new efforts emphasize monitoring to assess  the
 use and effectiveness of best management practices (BMPs). Recent 
 monitoring reveals that BMP use is increasing and that such use 
 typically maintains water quality within standards. However, 
 information is generally lacking about the cost effectiveness of
 BMP  programs. Carefully designed and executed monitoring is the
 key to  better specification of BMPs and more cost effective
 water quality  protection.
 NAL Call No.:  292.9-Am34
 81. Leaching of nitrogen and phsophorus from the biomass of three
 cover  crop species.
 Miller, M. H.; Beauchamp, E. G.; Lauzon, J. D. 
 J-environ-qual v.23, p.267-272. (1994).
 Includes references.
 Descriptors: trifolium-pratense; lolium-multiflorum;
 raphanus-sativus; cover- crops; nitrate-nitrogen;
 ammonium-nitrogen; phosphorus-; biomass-; leaching-;
 runoff-water; water-quality; rain-; freezing-; leachates-;
 drying-; temporal-variation; species-differences;
 Abstract: Cover crops, although they may reduce the leaching of
 NO3-N to  groundwater, may increase nutrient concentration in
 runoff because of  biomass leaching during rainfall events.  A
 simulated rainfall study  was conducted in the laboratory to
 determine the effects of freezing  alone and freezing plus drying
 treatments, loading rate, and rainfall  intensity on the leaching
 of NH4-N, NO3-N, and inorganic P from the  biomass of red clover
 (Trifolium pratense L.), annual ryegrass (Lolium  multiflorum
 L.), and oilseed radish [Raphanus sativus (L.) var.  oleifera Dc
 Metzg]. Concentration of P increased during early stages of 
 leaching, then decreased slowly but remained greater than 50% of
 the  maximum, even after the equivalent of 6.0 cm of simulated
 rainfall.  Concentrations of NO3-N were similar to P but changed
 less during  leaching.  Weighted mean concentrations of P ranged
 from less than 2.0  to more than 15 mg L-1.  Concentrations were
 greatest with oilseed  radish and least with red clover.  Drying
 the sample in addition to  freezing increased the P
 concentration, particularly in the initial  leaching.  About 30%
 of the biomass P was leached from oilseed radish  and annual
 ryegrass, but only about 20% from red clover.  Because  oilseed
 radish had a greater biomass P concentration, the total P 
 leached was much greater than for the other two species.  Between
 5 and  9% of the biomass N was leached as either NO3-N or NH4-N
 from ryegrass  and red clover while over 10% was leached from
 oilseed radish.  The  results indicate that cover crop species
 differed markedly in their  potential impact on nutrient
 concentration, particularly P, in runoff.   Of the three cover
 crops tested, oilseed radish.
 NAL Call No.:  QH540.J6
 82. Livestock manure management and water quality.
 Wheeler, G.; Miller, A. E. 
 Fact-sheet-Max-C-Fleischmann-Coll-Agric,-Coop-Ext-Serv. [Reno, 
 Nev.] : The College,. 1993. (93-52) 4 p. 
 Includes references.
 Descriptors: farmyard-manure; waste-disposal;
 application-to-land; nutrient- availability; nutrient-content;
 application-rates; chemical-analysis; water-quality;
 NAL Call No.:  S544.3.N3C66
 83. Long-term effect of tillage and rainfall on herbicide
 leaching to  shallow groundwater.
 Isensee, A. R.; Sadeghi, A. M. 
 Chemosphere v.30, p.671-685. (1995).
 Includes references.
 Descriptors: atrazine-; alachlor-; cyanazine-;
 herbicide-residues; leaching-; groundwater-pollution; rain-;
 tillage-; no-tillage-; lateral-movement; groundwater-;
 silt-loam-soils; maryland-; conventional-tillage;
 confined-groundwater; unconfined-groundwater
 NAL Call No.:  TD172.C54
 84. Managing agricultural phosphorus for protection of surface
 waters:  issues and options.
 Sharpley, A. N.; Chapra, S. C.; Wedepohl, R.; Sims, J. T.;
 Daniel, T. C.; Reddy, K. R. 
 J-environ-qual v.23, p.437-451. (1994).
 Includes references.
 Descriptors: phosphorus-; pollution-; soil-management;
 crop-management; losses- from-soil; eutrophication-; runoff-;
 erosion-; soil-fertility; manures- ; pollution-control;
 watershed-management; nonpoint-source-pollution
 Abstract: The accelerated eutrophication of most freshwaters is
 limited by P  inputs. Nonpoint sources of P in agricultural
 runoff now contribute a  greater portion of freshwater inputs,
 due to easier identification and  recent control of point
 sources. Although P management is an integral  part of profitable
 agrisystems, continued inputs of fertilizer and  manure P in
 excess of crop requirements have led to a build-up of soil  P
 levels, which are of environmental rather than agronomic concern, 
 particularly in areas of intensive crop and livestock production.
 Thus,  the main issues facing the establishment of economically
 and  environmentally sound P management systems are the
 identification of  soil P levels that are of environmental
 concern; targeting specific  controls for different water quality
 objectives within watersheds; and  balancing economic with
 environmental values. In developing effective  options, we have
 brought together agricultural and limnological  expertise to
 prioritize watershed management practices and remedial 
 strategies to mitigate nonpoint-source impacts of agricultural P. 
 Options include runoff and erosion control and P-source
 management,  based on eutrophic rather than agronomic
 considerations. Current soil  test P methods may screen soils on
 which the aquatic bioavailability of  P should be estimated.
 Landowner options to more efficiently utilize  manure P include
 basing application rates on soil vulnerability to P  loss in
 runoff, manure analysis, and programs encouraging manure 
 movement to a greater hectareage. Targeting source areas may be 
 achieved by use of indices to rank soil vulnerability to P loss
 in  runoff and lake sensitivity to P inputs.
 NAL Call No.:  QH540.J6
 85. Manure and wastewater management systems for open lot dairy 
 Sweeten, J. M.; Wolfe, M. L. 
 Trans-ASAE v.37, p.1145-1154. (1994).
 Includes references.
 Descriptors: cattle-manure; dairy-effluent; dairy-wastes;
 pollution-control; dairy-farming; dairies-; waste-treatment;
 waste-water-treatment; anaerobic-treatment; texas-
 Abstract: Dairy industry expansion using open lot designs has
 impacted water  quality and groundwater usage in parts of Central
 Texas. Field research  was conducted at commercial dairy farms in
 Erath County, Texas, to  develop improved design criteria for
 storage, treatment, and land  application systems for open lot
 dairies. Water use and waste water  from milking parlors were
 monitored along with rainfall runoff from  open lots. Water use
 for milk sanitation and manure removal averaged  148 L per cow
 per day. Two-stage anaerobic lagoon systems achieved  higher
 solids and nutrient removal efficiencies than a combination of 
 settling basin and one-stage anaerobic lagoons. The two-stage
 anaerobic  lagoon system with 81- to 118-day hydraulic retention
 time reduced  concentrations of volatile solids (VS), chemical
 oxygen demand (COD),  and total kjeldahl nitrogen (TKN) in dairy
 wastewater from milking  parlors by 80 to 82%, 90 to 93% and 55
 to 73%, respectively. Solids  settling basins reduced VS, COD,
 and TKN concentrations in wastewater  by 35 to 45%, 27 to 47%,
 and 14 to 24%, respectively. As compared to  second-stage lagoon
 effluent, open lot runoff was higher in K, but  similar in TKN
 and P concentrations and contained a greater proportion  affixed
 solids. Analysis showed that anaerobic lagoon effluent and open 
 lot runoff were good sources of available plant nutrients.
 NAL Call No.:  290.9-Am32T
 86. Marginal cost effectiveness analysis for agricultural
 nonpoint  source water quality control.
 Walker, D. J.; Calkins, B. L.; Hamilton, J. R. 
 J-Soil-Water-Conserv v.48, p.368-372. (1993).
 In the special edition: The next generation of U.S. agricultural 
 conservation policy. Paper presented at the conference "The Next 
 Generation of U.S. Agricultural Policy", March 14-16, Kansas
 City,  Missouri.
 Descriptors: water-quality; water-pollution; pollution-control;
 sediment-; marginal-analysis; cost-effectiveness-analysis;
 farm-management; furrow- irrigation; return-flow;
 NAL Call No.:  56.8-J822
 87. Metamodels and nonpoint pollution policy in agriculture.
 Bouzaher, A.; Lakshminarayan, P. G.; Cabe, R.; Carriquiry, A.;
 Gassman, P. W.; Shogren, J. F. 
 Water-resour-res v.29, p.1579-1587. (1993).
 Includes references.
 Descriptors: herbicides-; agricultural-chemicals; groundwater-;
 surface-water; water-pollution; water-quality; simulation-models;
 Abstract: Complex mathematical simulation models are generally
 used for  quantitative measurement of the fate of agricultural
 chemicals in soil.  But it is less efficient to use them directly
 for regional water  quality assessments because of the large
 number of simulations required  to cover the entire region and
 because the entire set of simulation  runs must be repeated for
 each new policy. To make regional water  quality impact
 assessment on a timely basis, a simplified technique  called
 metamodeling is suggested. A metamodel summarizes the input-
 output relationships in a complex simulation model designed to
 mimic  actual processes such as groundwater leaching. Metamodels
 are  constructed and validated to predict groundwater and surface
 water  concentrations of major corn and sorghum herbicides in the
 Corn Belt  and Lake States regions of the United States. The
 usefulness of  metamodeling in the evaluation of agricultural
 nonpoint pollution  policies is illustrated using an integrated
 environmental economic  modeling system. For the baseline
 scenario, we estimate that 1.2% of  the regional soils will lead
 to groundwater detection of atrazine  exceeding 0.12
 micrograms/L, which compares well with the findings of  an
 Environmental Protection Agency monitoring survey. The results 
 suggest no-till practices could significantly reduce surface
 water  concentration and a water quality policy, such as an
 atrazine ban,  could increase soil erosion despite the
 conservation compliance  provisions.
 NAL Call No.:  292.8-W295
 88. Minimizing nitrate losses from arable soils.
 Shepherd, M. A.; Davies, D. B.; Johnson, P. A. 
 Soil-use-manage v.9, p.94-99. (1993).
 Paper presented at the National Agricultural Conference,
 "Nitrogen  management in a changing environment," January 29,
 1992, Stoneleigh,  Warwickshire.
 Descriptors: arable-soils; nitrate-; losses-from-soil; leaching-;
 pollution- control
 Abstract: Recent experiments on soils overlying sand, chalk and
 limestone  aquifers have shown that nitrate  leaching losses can
 be decreased by  modifying crop husbandry.  Green cover during
 winter, if   established  early enough, can reduce nitrate loss. 
 Cultivations can be timed to  minimize   leaching, and the
 advantages of irrigation (increased  nitrogen offtake and smaller
 post-harvest   soil mineral nitrogen  residues) outweigh the
 potential disadvantage of increased leaching  risk   during the
 growing season.  It is important not to over- fertilize crops.
 Using these techniques   within farm rotations has  decreased
 nitrate losses in small plot experiments.  The next step is  to  
 measure the effects on commercial farms where the scale of 
 operation might preclude the high level   of husbandry that is
 required  for successful nitrogen management.
 NAL Call No.:  S590.S68
 89. Modeling alternatives to reduce dairy farm and watershed
 nonpoint  source pollution.
 Sugiharto, T.; McIntosh, T. H.; Uhrig, R. C.; Lardinois, J. J. 
 J-environ-qual v.23, p.18-24. (1994).
 Technical Reports from the Symposium, "Minimizing Agricultural 
 Nonpoint-Source Impacts", November 2, 1992, Minneapolis,
 Descriptors: zea-mays; avena-sativa; medicago-sativa;
 cropping-systems; tillage- ; no-tillage-; anhydrous-ammonia;
 manures-; simulation-models; sediment- yield; phosphorus-;
 yields-; watersheds-; dairy-farms; water-pollution; wisconsin-
 Abstract: Management practices are available that may reduce
 sediment or  phosphorus (P) loading to streams draining
 agricultural land.  An  evaluation of the long term effects of
 implementing one or more of  these practices is needed.  We used
 the Erosion Productivity Impact  Calculator (EPIC) and
 Agricultural Non-Point Source (AGNPS) models to  evaluate 20
 management practices for sediment and P yields from 4 ha  fields
 in a 1272 ha watershed of dairy farms. Five crop sequences 
 [continuous corn (Zea mays L.) CC(OA)AAA, CC(OA)AAAA, CCC(OA)AAA,
 and  CCCAAA; 0, oat (Avena sativa L.); A, alfalfa (medicago
 sativa L.)]  combined with either fall moldboard plowing (mFMP),
 chisel plow (mFCP),  no-till (mNT), or no-till substituting
 anhydrous ammonia for manure  (aNT), were imposed on a
 toposequence of three Alfisols.  The normal  sequence, 2 yr of
 corn, oat/alfalfa seeding, 3 yr of alfalfa with fall  application
 of solid manure followed by moldboard plowing, CC(OA)AAA- mFMP,
 served as reference. Scenarios were subjected to 42 yr of 
 simulated local climate.  Scenarios with 43% or less row crop and
 mNT  on a 4% sloping soil reduced sediment yield from 24 to 47%,
 at edge of  field, but increased total P yield from 158 to 338%,
 mostly as soluble  P. The EPIC output parameters (soil loss ratio
 [C] for June,  erodibility [K], Manning's n, and SCS curve number
 [CN]) served as  inputs to the (AGNPS) model, a cell based single
 rainfall event model  that simulates runoff, sediment, and P
 yields from a watershed.  Crop  sequences not exceeding 43% corn
 and mFCP or aNT reduced watershed  sediment yield 13 to 41%, but
 increased total P yield by 44 to 113% as  compared with
 CC(OA)AAA-mFMP.  Average annual costs were $11 ha-1 less.
 NAL Call No.:  QH540.J6
 90. A modeling approach to evaluate best management practices.
 Williams, R. D.; Nicks, A. D. 
 Water-sci-technol v.28, p.675-678. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: agricultural-land; crops-; river-water;
 water-pollution; protection- ; soil-management; water-quality;
 improvement-; models-; usa-; vegetative-filter-strips
 NAL Call No.:  TD420.A1P7
 91. Modeling linked watershed and lake processes for water
 quality  management decisions.
 Summer, R. M.; Alonso, C. V.; Young, R. A. 
 J-Environ-Qual v.19, p.421-427. (1990).
 Includes references.
 Descriptors: watersheds-; lakes-; agricultural-land;
 simulation-models; water- quality; sediment-; nitrogen-;
 phosphorus-; chlorophyll-; wetlands-; watershed-management;
 weather-; trends-; farming-systems;
 agricultural-nonpoint-source-model-agnps; suspended-sediment;
 best- management-practices
 Abstract: A physically based modeling approach is used to link
 watershed with  lake processes and to simulate their responses to
 land management and  weather conditions. Components of the
 watershed model, AGNPS  (agricultural nonpoint-source model), are
 hydrology, erosion, sediment  transport, transport of nitrogen
 and phosphorus, and chemical oxygen  demand. Using a cellular
 structure, runoff, sediment, and chemical  variables from the
 watershed provide input to a take model. This one- dimensional
 model of water bodies simulates temperature stratification, 
 mixing by wind, sedimentation, inflow density current, and algal 
 growth. Unsteady advection-diffusion equations characterize the 
 dynamics of suspended sediment, soluble and sediment-attached N
 and P,  and chlorophyll. This model, AGNPS-LAKE, is driven by
 random generation  of weather conditions on a daily basis.
 Resulting impacts of  alternative management plans are simulated
 by changing agricultural  practices and land use, thereby
 modifying inflow characteristics to a  lake. Modeling
 capabilities are being tested on eutrophic lakes in  Minnesota
 for the purpose of simulating long-term trends and impacts of 
 best management practices.
 NAL Call No.:  QH540.J6
 92. Modification of RZWQM for simulating subsurface drainage by
 adding  a tile flow component.
 Singh, P.; Kanwar, R. S. 
 Trans-ASAE v.38, p.489-498. (1995).
 Includes references.
 Descriptors: subsurface-drainage; water-quality; water-flow;
 rain-; soil- properties; tillage-; simulation-models;
 computer-simulation; performance-appraisals
 Abstract: Fluctuating water table and subsurface drain flow
 components were  incorporated in the Root Zone Water Quality
 Model (RZWQM) to enable the  model to simulate subsurface drain
 flows. Parameters in a modified  model were calibrated using
 observed subsurface drain flows for 1990.  Model performance was
 evaluated by predicting subsurface drain flows  for 1991 and 1992
 by using the calibrated parameters and comparing the  predicted
 drain flows with observed subsurface drain flows for the same 
 years. The modified RZWQM model, in general, showed a good
 response to  rainfall in terms of time of peak flows. However,
 the modified RZWQM  model overpredicted total tile flows by an
 average of 13%, and the  magnitudes of peak tile flows were
 generally underpredicted Selected  soil properties (bulk density,
 macroporosity, and residue content) in  the surface horizon were
 changed to investigate tillage effects on tile  flows using the
 modified RZWQM. Four different tillage systems, chisel  plow
 (CP), moldboard plow (MB), no-tillage (NT), and ridge-tillage
 (RT) , were considered. Predicted tillage effects on subsurface
 drain flows  were consistent with the observed effects (i.e.,
 maximum tile flow for  NT and minimum tile flow for MB).
 NAL Call No.:  290.9-Am32T
 93. The Moores Creek BMP effectiveness monitoring project.
 Edwards, D. R.; Daniel, T. C.; Murdoch, J. F.; Vendrell, P. F. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Summer 1993. (932085) 26 p. 
 Paper presented at the "1993 International Summer Meeting
 sponsored  by The American Society of Agricultural Engineers, and
 The Canadian  Society of Agricultural Engineering," June 20-23,
 1993, Spokane,  Washington.
 Descriptors: poultry-manure; runoff-water; water-quality;
 NAL Call No.:  290.9-Am32P
 94. Nitrate contamination of groundwater under irrigated coastal
 plain  soils.
 Weil, R. R.; Weismiller, R. A.; Turner, R. S. 
 J-Environ-Qual v.19, p.441-448. (1990).
 Includes references.
 Descriptors: nitrate-nitrogen; groundwater-; coastal-plain-soils;
 farmland-; leaching-; poultry-manure; nitrogen-fertilizers;
 center-pivot- irrigation; precipitation-; soil-depth;
 phosphates-; ammonium-nitrogen; chloride-; forests-;
 groundwater-pollution; maryland-
 Abstract: To develop best management practices (BMP) for
 agricultural land to  protect groundwater, data is needed on the
 leaching of N from irrigated  coastal plain soils treated with
 Poultry manure. This study was  conducted to determine the
 vertical and seasonal patterns of NO3  leaching under such soils.
 Four commercially farmed corn (Zea mays L.)  fields were studied,
 two receiving only fertilizer N (240 to 360 kg N  ha-1 over a
 2-yr period) and two with a continuing history of poultry  manure
 applications (25-29 Mg ha-1 over 2 yr). In each field, a 
 transect of four monitoring wells was installed 4 to 8 m deep (1
 m  below the seasonally low water table). Three additional wells
 were  installed in forestland adjacent to three of the fields.
 Groundwater  and soils (to 1.5-m depth) were periodically sampled
 for analysis of  NO3(-)N. Under the unmanured field, groundwater
 concentrations averaged  15.1 mg L-1 during August through
 November 1986, while the  corresponding figure for the manured
 fields was not significantly  different at 18.3 mg L-1. Two
 months after spreading manure in November  and December, as much
 as 104 mg NO3(-)N was measured in the groundwater  under the
 manured fields. From December 1986 through September 1987 the 
 groundwater under the manured fields had significantly higher
 NO3(-)N  concentrations than did that under the unmanured fields
 (43.7 vs. 18.1  mg L-1, respectively). Only for one well site
 with a buried A horizon  did high Cl to NO3(-)N ratios and low
 N)3(-)N concentrations indicate  rapid denitrification. The
 forestland groundwater always contained < 1  mg NO3(-)N L-1, and
 high Cl to NO3(-)N ratios, suggesting that NO3 in  the cropland
 groundwater was lost after entering the forested areas,  and that
 forests may therefore protect waterways from subsurface N 
 NAL Call No.:  QH540.J6
 95. Nitrate leaching in a udic haploboroll as influenced by 
 fertilization and legumes.
 Campbell, C. A.; Lafond, G. P.; Zentner, R. P.; Jame, Y. W. 
 J-environ-qual v.23, p.195-201. (1994).
 Includes references.
 Descriptors: nitrate-nitrogen; leaching-; triticum-aestivum;
 rotations-; summer- fallow; fertilization-; medicago-sativa;
 green-manures; soil-water; soil-testing; nitrogen-fertilizers;
 application-rates; groundwater- pollution; udic-regimes;
 Abstract: An ongoing 34-yr crop rotation experiment being
 conducted on a  heavy clay at Indian Head, SK, allowed a
 snap-shot assessment to he  made of the influence of
 fertilization, legume green manure and legume- grass hay crops,
 and frequency of cropping to monoculture hard red  spring wheat
 (Triticum aestivum L.) on deep leaching of soil nitrate  (NO3). 
 The results showed that NO3 leaching was greatest when summer 
 fallowing was most frequently employed.  Although N fertilization
 may  increase NO3-N leached, using a soil test as a guide to
 choosing  fertilizer application rates and cropping annually will
 minimize NO3  leaching.  Further, we found that, although
 deep-rooted forage crops  such as alfalfa (Medicago sativa L.)
 remove NO3 and water to a depth of  2.4 m, and because legumes
 increase the N supplying power of the soil,  considerable NO3
 leaching can still occur under these systems. This is  especially
 true if legume plowdown is followed by a fallow period,  because
 during the fallow period, copious net N mineralization may  occur
 together with increased soil moisture storage. These results do 
 not imply that leaching is pervasive on the Canadian Prairies,
 but they  do confirm certain well-known principles: viz., that
 NO3 leaching can  be expected whenever conditions favor NO3
 accumulation and water  buildup in soil.  Consequently, it is
 important to keep the land  cropped for a large proportion of the
 time and to use fertilizers at  moderate rates based on soil
 NAL Call No.:  QH540.J6
 96. Nitrate leaching in dryland agroecosystems as influenced by
 soil  and climate gradients.
 Evans, S. D.; Peterson, G. A.; Westfall, D. G.; McGee, E. 
 J-environ-qual v.23, p.999-1005. (1994).
 Includes references.
 Descriptors: nitrate-nitrogen; leaching-; losses-from-soil;
 agricultural-soils; evapotranspiration-; soil-water-content;
 climatic-zones; site-factors; dry-farming; colorado-
 Abstract: Farmers in dryland agriculture areas of the Central
 Great Plains  have characteristically practiced alternate
 crop-fallow to stabilize  yields. Large amounts of N released
 soon after sodbreaking and more  recent fertilizer additions may
 have contributed to N movement below  crop root zones. Improved
 water conservation techniques during fallow  periods increases
 the possibility of NO3 leaching below root zones in  modern-day
 crop-fallow systems. Soil topography and water supply may  affect
 leaching potential. This study was conducted to test hypotheses 
 regarding landscape position effects and potential
 evapotranspiration  on depth of water and NO3 penetration. Three
 sites in eastern Colorado  with equal annual precipitation, but
 with mean potential  evapotranspiration varying from 1000 to 1900
 mm yr-1 were evaluated. A  soil catena was sampled at each site
 to test landscape effects. All  sites were previously managed
 under tilled wheat-fallow systems for at  least 50 yr. All summit
 (upland) sites had higher water and NO3  contents below their
 crop root zones than nearby native prairie sites.  Soil water and
 NO3 content of soil profiles to a depth of 9 m were not  related
 to slope position, but there was an inverse relationship  between
 water and NO3 content of soil profiles and potential 
 evapotranspiration. The total NO3-N in cultivated profiles below
 the  normal root zone of crops varied from 126 kg ha-1 at the
 northern site  to 47 kg ha-1 at the southern site. Although some
 NO3 leaching had  occurred, it did not appear to be a major
 problem for any particular  landscape position or climatic zone
 on cultivated soils.
 NAL Call No.:  QH540.J6
 97. Nitrate leaching to a shallow mid-Atlantic Coastal Plain
 aquifer as  influenced by conventional no-till and low-input
 sustainable grain  production systems.
 Craig, J. P.; Weil, R. R. 
 Water-sci-technol v.28, p.691-700. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: nitrates-; leaching-; aquifers-; coastal-plains;
 groundwater- pollution; pollution-control; cropping-systems;
 grain-crops; no-tillage- ; sustainability-; maryland-
 NAL Call No.:  TD420.A1P7
 98. Nitrous oxide emissions from fertilized soils: summary of
 available  data.
 Eichner, M. J. 
 J-Environ-Qual v.19, p.272-280. (1990).
 Literature review.
 Descriptors: nitrous-oxide; emission-; atmosphere-; fertilizers-;
 agricultural- soils; environmental-factors; crop-management;
 soil-types; farming- systems; trends-; global-warming;
 ozone-depletion; literature-reviews
 Abstract: Direct measurements of fertilizer-derived N2O emission
 data from  104 field experiments reported in agriculture and soil
 science  literature that were obtained between 1979 and 1987 were
 summarized and  used to estimate worldwide fertilizer-derived N2O
 emissions. Although  without statistical determination, there
 appears to be a trend between  emissions and type and quantity of
 fertilizer applied; the available  data does not indicate a trend
 between emissions and a particular soil  type or agriculture
 system. Using the fraction of the N fertilizer  evolved as N2O
 and fertilizer consumption estimates for five fertilizer  types,
 0.1 to 1.0 Tg N2O-N (avg. 0.3; median 0.2) were estimated to be 
 released during the "sampling period". If these estimates are
 doubled  to account for emissions after the sampling period and
 emissions from  fertilizer lost in drainage water and
 groundwater, the expected range  would be 0.2 to 2.1 Tg N2O-N
 (avg. 0.7; median 0.5) emitted into the  atmosphere in 1984. The
 magnitude of this estimate is in agreement with  recent global
 estimates. If 100 Tg N fertilizer are consumed worldwide  in the
 year 2000, the global release of fertilizer-derived emissions 
 into the atmosphere will probably not exceed 3 Tg N2O-N in the
 year  2000. It is estimated that 23 to 315 Gg N2O-N were emitted
 into the  atmosphere from fields of cultivated leguminous crops
 in 1986. Future  research needs were suggested.
 NAL Call No.:  QH540.J6
 99. Nonpoint source pollution impacts of alternative agricultural 
 management practice in Illinois: a simulation study.
 Phillips, D. L.; Hardin, P. D.; Benson, V. W.; Baglio, J. V. 
 J-soil-water-conserv v.48, p.449-457. (1993).
 Includes references.
 Descriptors: erosion-; carbon-; nutrient-balance; rotations-;
 water-pollution; no-tillage-; alternative-farming;
 innovation-adoption; simulation- models; zea-mays; glycine-max;
 crop-yield; nitrogen-; phosphorus-; runoff-; illinois-;
 soil- carbon; nutrient-exports
 NAL Call No.:  56.8-J822
 100. Nutrient and water management practices for sustainable
 vegetable  production in the Lake Apopka Basin.
 Neal, C. A.; Hanlon, E. A.; White, J. M.; Cox, S.; Ferrer, A. 
 Environmentally sound agriculture  proceedings of the second 
 conference  20-22 April 1994 / p.276-279. (1994).
 Includes references.
 Descriptors: vegetable-growing; histosols-; management-;
 water-management; phosphorus-; losses-from-soil; sustainability-;
 projects-; water- quality; environmental-impact; florida-;
 NAL Call No.:  S589.7.E57-1994
 101. Nutrient concentrations in southern United States shallow
 ground  water and surface runoff.
 Schreiber, J. D. 
 Proceedings of Industrial and Agricultural Impacts on the 
 Hydrologic Environment  the Second USA/CIS Joint Conference on 
 Environmental Hydrology and Hydrogeology / USA/CIS Joint
 Conference on  Environmental Hydrology and Hydrogeology.
 Alexandria, VA : Water  Environment Federation, c1993.. p.
 Title on cover : Environmental impact of agricultural practices
 and  agrichemicals / edited by Y. Eckstein and A. Zaporozec.
 Descriptors: glycine-max; triticum-aestivum; winter-; wheat-;
 no-tillage-; minimum-tillage; watersheds-; groundwater-pollution;
 surface-water; runoff-; nutrient-content; groundwater-level;
 fragipans-; fertilizers-; application-methods; loess-soils;
 nutrients-; losses-; mississippi-
 NAL Call No.:  GB652.U82-1993
 102. Performance of on-site domestic wastewater renovation
 systems  specified for sites with shallow soils.
 Mote, C. R.; Buchanan, J. R.; Ammons, J. T. 
 Appl-eng-agric v.11, p.437-447. (1995).
 Includes references.
 Descriptors: waste-water; waste-water-treatment; soil-depth;
 seepage-; macropore- flow; tillage-; literature-reviews;
 water-quality; usa-; seepage-beds
 Abstract: Observation of two on-site domestic wastewater
 renovation systems  indicate that a soil as shallow as 45 cm (18
 in.) has considerable  potential for renovating septic tank
 effluent. However, system design  determines, to a great extent,
 the degree of renovation that occurs.  Important design features
 identified are wider seepage beds (or lower  seepage bed loading
 rates) than are currently specified by some  established design
 procedures, and a tilled soil layer beneath seepage- bed
 aggregate. Wider seepage beds disperse water more completely 
 throughout a soil profile and promote more micro-pore flow.
 Thorough  tillage of soil beneath seepage beds disrupts macro
 pore continuity and  pro notes more flow in micro pores where the
 resulting extended  soil/wastewater contact promotes renovation.
 NAL Call No.:  S671.A66
 103. Pesticide contamination of groundwater in Virginia: BMP
 impact  assessment.
 Mostaghimi, S.; McClellan, P. W.; Cooke, R. A. 
 Water-sci-technol v.28, p.379-387. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: groundwater-pollution; pesticides-; water-quality;
 improvement-; watersheds-; monitoring-; systems-; agronomy-;
 techniques-; wells-; virginia-; best-management-practices
 NAL Call No.:  TD420.A1P7
 104. Precision nutrient management--impact on the environment and
 needs  for the future.
 Swader, F.; Woodward, M. 
 Commun-soil-sci-plant-anal. New York, N.Y. : Marcel Dekker. 1994. 
 v. 25 (7/8) p. 881-888. 
 Paper presented at the 1993 International Symposium on Soil
 Testing  and Plant Analysis: Precision Nutrient Management,
 August 14-19, 1993,  Olympia, Washington. Part 1.
 Descriptors: water-quality; water-pollution; point-sources;
 pollution-control; nutrients-; management-; application-to-land;
 environmental-protection; profitability-; trends-; regulations-;
 trends-; sustainability-; usa-; nutrient-loading;
 NAL Call No.:  S590.C63
 105. Preliminary evaluation of effects of best management
 practices in  the Black Earth Creek, Wisconsin, priority
 Walker, J. F.; Graczyk, D. J. 
 Water-sci-technol v.28, p.539-548. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: watersheds-; water-quality; surface-water;
 water-pollution; agricultural-land; runoff-; erosion-control;
 soil-management; wisconsin- 
 NAL Call No.:  TD420.A1P7
 106. Procedures for assessing the effectiveness of best
 management  practices in protecting water and stream quality
 associated with  managed forests.
 National Council of the Paper Industry for Air and Stream
 Improvement (U.S.). 
 New York, N.Y. : National Council of the Paper Industry for Air
 and  Stream Improvement, [1988] 1 v. (various pagings) : ill.,
 Cover title.
 Descriptors: Forest-management; Water-quality
 NAL Call No.:  TD899.P3N34-no.538
 107. Profits and nitrate leaching under irrigated corn: a
 Miller, G. D.; Hanks, R. J.; Andersen, J. C.; Erkison, G. R. 
 Irrig-sci. Berlin, W. Ger. : Springer International. 1993. v. 13
 (4) .
 Includes references.
 Descriptors: zea-mays; irrigated-stands; nitrate-; leaching-;
 pollution-control; economic-impact; profits-; simulation-
 Abstract: The economic impact of reducing the amount of nitrate
 leached out  of the root zone under irrigation in the arid West
 was examined. The  economic incentives of irrigation management
 were evaluated under the  assumptions of both profit-maximizing
 and utility-maximizing (in  reducing cost and effort expended in
 irrigation) decision-making  criteria. The results indicate that
 there is a coincidence of interests  of the farmer and the
 environment provided some leaching occurred. If  no leaching is
 allowed, profit decreases markedly. Both behaviors  result in
 less nitrate leaching than less profitable or less utility 
 producing irrigating practices.
 NAL Call No.:  S612.I756
 108. Reducing soil erosion and agricultural chemical losses with 
 conservation tillage.
 Seta, A. K.; Blevins, R. L.; Frye, W. W.; Barfield, B. J. 
 J-environ-qual v.22, p.661-665. (1993).
 Includes references.
 Descriptors: conservation-tillage; chiselling-; no-tillage-;
 runoff-water; losses-from-soil; water-quality; nitrate-nitrogen;
 ammonium-nitrogen; phosphates-; atrazine-; kentucky-
 Abstract: As nonpoint source pollution of water becomes more
 evident, more  concern is being focused on the   effects of
 agricultural practices on  water quality. This study evaluated
 the effects of  conventional  tillage (CT), chisel-plow tillage
 (CP), and no tillage (NT) on the  quality of runoff   water from
 a Maury silt loam soil (fine, mixed,  mesic Typic Paleudalf) near
 Lexington, KY. The   mean runoff rate,  total runoff volume, mean
 sediment concentration, and total soil losses  were  
 significantly less for NT than for CP and CT. Concentration of 
 NO3-, NH4+, and PO4(3-) in the   runoff water from NT were
 greater than  from CP or CT. Concentration of atrazine 
 [6-chloro-N-ethyl-N'-(1- methylethyl)-1,3,
 5-triazine-2,4-diamine] in the runoff water tended to  be  higher
 from CP than from NT or CT. Total losses of NO3-, NH4+,  PO4(3-),
 and atrazine in runoff   water were generally in the order CT  >
 CP > NT. The sum of all chemicals lost was less than 3% of   the 
 total amount of each applied.
 NAL Call No.:  QH540.J6
 109. Relationship between salinity and efficient water use.
 Letey, J. 
 Irrig-sci. Berlin, W. Ger. : Springer International. 1993. v. 14
 (2) .
 Paper presented at the First Volcani International Symposium on
 The  Limits of Water Use Efficiency in Agriculture, October 1992,
 Bet Dagan,  Israel.
 Descriptors: salinity-; saline-water; water-use-efficiency;
 irrigation-water; water-management
 Abstract: The relationship between salinity and water use
 efficiency is  highly dependent upon which   definition of water
 use efficiency is  used. The two common definitions, yield per
 unit   evapotranspiration  and yield per unit applied water, both
 have significant deficiencies  and can  lead to erroneous
 conclusions. Thus, the analysis of efficient  use of saline
 waters invokes a   broader analysis than merely computing  water
 use efficiency. An array of models is available to   simulate the 
 effects of various irrigation management strategies with saline
 waters.  Based on   results computed from these models, which
 consider the  osmotic and matric potential effects on   plant
 growth, strategies can  be developed to effectively use saline
 waters in crop production. The    cyclic strategy of using waters
 of different salinities can effectively  be used in maintaining 
 crop rotations which include both salt- sensitive and
 salt-tolerant crops. The major deficiency of   the models  is
 that they do not account for the effects of water quality on soil 
 physical   conditions with consequent effects on crop production. 
 Indeed, the most limiting factor in use of   saline waters on
 soils may  be deterioration of soil physical conditions. The
 deterioration of soil  waters per se but from subsequent  
 rainfall or low salinity waters.  Thus far the emphasis on using
 saline waters on crop production  has  centered on yields and
 less attention has been given to the long-term  consequences on
 soil. be a focus of attention in   future experiments. Relatively
 high saline  water tables can be maintained without drainage if a 
  non-saline  source of water is available, and irrigation amounts
 can be controlled.  This strategy   might invoke the necessity
 for shifting irrigation  systems from surface to pressurized
 systems.   Eventually, some salt  must be removed from the
 system. It is probably more efficient to allow  it to become very
 concentrated and remove small volumes to be  disposed of in some
 manner rather than  apply it to prodctive land.
 NAL Call No.:  S612.I756
 110. Relationship between soil test methods and uptake of copper
 and  zinc by grasses on polluted soils.
 Singh, R. S.; Singh, R. P.; Rai, R. K.; Agrawal, H. P. 
 Commun-soil-sci-plant-anal. New York, N.Y. : Marcel Dekker. 1994. 
 v. 25 (9/10) p. 1313-1320. 
 Paper presented at the 1993 International Symposium on Soil
 Testing  and Plant Analysis: Precision Nutrient Management. II.,
 August 14-19,  1993, Olympia, Washington.
 Descriptors: cynodon-dactylon; cyperus-rotundus; polluted-soils;
 copper-; zinc-; nutrient-uptake; correlation-; soil-testing;
 nutrient-availability; extractants-; comparisons-
 NAL Call No.:  S590.C63
 111. Residual soil nitrate under intensive agriculture.
 Hofman, G.; Smet, J. de.; Meirvenne, M. v.; Verstegen, P. 
 Commun-soil-sci-plant-anal. New York, N.Y. : Marcel Dekker. 1994. 
 v. 25 (9/10) p. 1197-1207. 
 Paper presented at the 1993 International Symposium on Soil
 Testing  and Plant Analysis: Precision Nutrient Management. II.,
 August 14-19,  1993, Olympia, Washington.
 Descriptors: agricultural-soils; intensive-farming; nitrate-;
 nitrogen-content; residues-; regional-surveys; water-pollution;
 risk-; belgium-; residual-nitrate-content
 NAL Call No.:  S590.C63
 112. Residue management for winter wheat and grain sorghum
 production  with limited irrigation.
 Unger, P. W. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  Mar/Apr 1994. v. 58 (2) p. 537-542. 
 Includes references.
 Descriptors: triticum-aestivum; winter-wheat; sorghum-bicolor;
 rotations-; irrigated-conditions; crop-residues; management-;
 conservation-tillage; soil-water-content; soil-water-retention;
 water-use; crop-yield; yield- components; water-use-efficiency;
 water-conservation; crop-residue-management
 Abstract: Winter wheat (Triticum aestivum L.) and grain sorghum
 [Sorghum  bicolor (L.) Moench] are extensively grown in the
 southern Great Plains  on dryland and with irrigation, but yields
 often are low on dryland and  irrigation water is limited.
 Because both crops respond well to timely  irrigation, they
 sometimes are grown with limited irrigation. Thus, it  was
 hypothesized that using limited irrigation for these crops would 
 produce sufficient residues to increase soil water storage if 
 conservation tillage practices were used. This study on Pullman
 soil  (fine, mixed, thermic Torrertic Paleustoll) at Bushland,
 TX, determined  the effects of residue management on soil water
 storage and use,  yields, and yield components for wheat and
 sorghum grown in rotation  with limited irrigation. Treatments
 were no-tillage with standing (T1)  or shredded (T2) residues,
 and no-tillage after wheat and tillage after  sorghum (T3).
 Tillage did not affect water storage after wheat, but  storage
 ranged from 68 mm to T3 to 101 mm with T1 after sorghum. Water 
 use by wheat ranged from 93 mm with T3 to 131 mm with T1, but
 tillage  did not affect water use by sorghum. Tillage did not
 affect wheat  yields because differences in soil water storage
 and use were small and  irrigations minimized the water content
 differences. Tillage did not  affect sorghum yields because using
 no-tillage during fallow after  wheat resulted in similar water
 storage in all cases. This study showed  that practices that
 retain surface residues are effective for producing  wheat and
 grain sorghum in rotation under limited-irrigation conditions  in
 the southern Great Plains.
 NAL Call No.:  56.9-So3
 113. Residue management impact on the environment.
 Sims, G. K.; Buhler, D. D.; Turco, R. F. 
 Managing agricultural residues /. Boca Raton : Lewis Publishers, 
 c1994.. p. 77-98. 
 Includes references.
 Descriptors: crop-residues; crop-management;
 conservation-tillage; tillage-; no- tillage-;
 transport-processes; losses-from-soil; runoff-; pesticides-;
 fertilizers-; nutrients-; leaching-; soil-properties;
 water-quality; surface-water; water-pollution;
 NAL Call No.:  S604.M28-1994
 114. Reversing yield declines of a sub-tropical vertisol.
 Bell, M. A.; Lafitte, H. R.; Edmeades, G. O.; Chapman, S. C. 
 Commun-soil-sci-plant-anal v.26, p.1105-1119. (1995).
 Includes references.
 Descriptors: zea-mays; vertisols-; crop-yield; soil-fertility;
 soil-degradation; soil-structure; soil-water-content; drainage-;
 calcium-; bicarbonates-; iron-; chlorosis-; irrigation-water;
 water-quality; cover-crops; rotations-; land-improvement; mexico-
 Abstract: Problems of declining yield and increased chlorosis
 have been noted  for maize (Zea mays) grown at CIMMYT's
 experiment station at  Tlaltizapan, Mexico. Yields predicted by a
 crop model based on  temperature and incident radiation showed no
 decline with time,  suggesting that the problem was related to
 soil factors and/or  management. Neither soil organic matter
 (SOM) nor pH were implicated,  as SOM increased by 58%, and soil
 pH remained unchanged over the 15  years studied. Through a
 procedure of spatial and temporal analysis,  the problem was
 hypothesized to be a combination of bicarbonate ion  (HCO3(-))
 induced iron (Fe) chlorosis and soil structure deterioration. 
 Given this hypothesis, a trial was established to evaluate the
 effect  of different cover crops on soil moisture and the
 subsequent yield of  maize. In addition, blocks were sown to
 alfalfa (Medicago sativa) with  the intention that drying of the
 soil profile would re-establish soil  structure. Yield results
 from the cover crop trial, plus improvements  in infiltration and
 growth in blocks sown to alfalfa, supported the  conclusion that
 changes in management could, at least partially,  ameliorate the
 degradation of soil structure on this station.
 NAL Call No.:  S590.C63
 115. Ridge height and furrow blocking effects on water use and
 grain  yield.
 Unger, P. W. 
 Soil-Sci-Soc-Am-J v. 56, p.1609-1614. (1992).
 Includes references.
 Descriptors: triticum-aestivum; sorghum-bicolor; rotations-;
 water-conservation; water-use; ridges-; height-; furrows-; dams-;
 no-tillage-; conservation- tillage; soil-water-content;
 crop-yield; texas-; reduce-tillage
 Abstract: Because water supplies are limited for crops in the
 Great Plains,  use of water-conserving practices is important.
 This study determined  the influence of ridge height and furrow
 blocking on water conservation  and use, and yields of irrigated
 winter wheat (Triticum aestivum L.)  and dryland grain sorghum
 [Sorghum bicolor (L.) Moench] grown in  rotation. The rotation
 results in two crops in 3 yr with a 330-d fallow  between each
 crop. The study was conducted from 1981 to 1990 at  Bushland, TX,
 on Pullman clay loam (fine, mixed, thermic Torrertic 
 Paleustoll), Ridge heights were 12 to 15 or 5 to 8 cm and furrows
 were  blocked or open. The ridge-height and furrow-blocking
 treatments were  imposed every 3 yr before planting wheat.
 No-tillage was used during  fallow after wheat and reduced
 tillage was used to reform the ridges  during fallow after
 sorghum. Water infiltration was little affected by  treatments.
 Differences in soil water content at planting and harvest  wert
 significant in some cases, but trends were inconsistent. Total 
 water use was not affected by ridge height, but was greater with
 open  than with blocked furrows for wheat. Although significant
 in some  years, mean wheat and sorghum yield differences were
 small. On gentle  (< 0.5%) slopes, furrow blocking in combination
 with no-tillage and  reduced tillage did not increase soil water
 storage or crop yields over  those obtained with no-tillage
 alone. There was no indication that long- term no-tillage and
 reduced-tillage practices adversely affect wheat  and grain
 sorghum production.
 NAL Call No.:  56.9-SO3
 116. Role of information in the adoption of best management
 practices  for water quality improvement.
 Feather, P. M.; Amacher, G. S. 
 Agric-econ v. 11, p.159-170. (1994).
 Includes references.
 Descriptors: water-quality; information-; incentives-;
 farm-management; innovation-adoption; profitability-;
 demonstration-farms; federal- programs; usda-;
 mathematical-models; usa-; demonstration-projects
 Abstract: This study investigates the role of information in
 influencing the  adoption of improved farm management practices.
 A lack of producer  information regarding both the profitability
 and the environmental  benefits of adopting improved practices
 may be a reason why widespread  adoption of these practices has
 not occurred. Compared to direct  regulation or financial
 incentives, raising producer information levels  may be a more
 cost-effective method of increasing adoption. The United  States
 Department of Agriculture has recently established and begun 
 implementing a program based on this idea. To test the validity
 of the  program, a two-stage adoption model is specified and
 estimated using  data from a survey of producers in the program
 area. The results  indicate that producer perceptions play an
 important role in the  decision to adopt. Changing these
 perceptions by means of an  educational program may be a
 reasonable alternative to financial  incentives in encouraging
 BMP adoption.
 NAL Call No.:  HD1401.A47
 117. Simulating NO3-N transport to subsurface drain flows as
 affected by  tillage under continuous corn using modified RZWQM.
 Singh, P.; Kanwar, R. S. 
 Trans-ASAE v.38, p.499-506. (1995).
 Includes references.
 Descriptors: subsurface-drainage; water-flow; water-quality;
 nitrate-nitrogen; tillage-; simulation-models;
 computer-simulation; performance- appraisals
 Abstract: The Root Zone Water Quality Model (RZWQM) was
 previously modified  to simulate subsurface drain flows and
 evaluate the impact of different  tillage systems on subsurface
 drain flows (Singh and Kanwar, 1994).  This article discusses
 further modifications made in the RZWQM to  simulate
 nitrate-nitrogen (NO3-N) concentrations and N03-N losses with 
 subsurface drain flows. Daily NO3-N concentrations were simulated
 in  subsurface drain flows under four different tillage systems:
 chisel  plow (CP), moldboard plow (MB), no-tillage (NT), and
 ridge-nllage (RT)  by using the modified RZWQM. Simulations were
 conducted for the growing  seasons of three years (1990 to 1992).
 Simulated N03-N concentrations  and losses with subsurface drain
 flows were compared with the measured  data obtained from a water
 quality research site at Nashua, Iowa.  Predicted NO3-N
 concentrations generally followed the same pattern as  the
 observed concentrations. Simulated annual average NO3-N 
 concentrations in subsurface drain flows were within 11%
 (averaged over  all three years) of observed annual average NO3-N
 concentrations in  subsurface drain flows. The model correctly
 predicted maximum  concentrations under MB treatment and minimum
 under NT for all three  years. Simulated annual NO3-N losses were
 within 14% (averaged over all  three years) of observed annual
 NO3-N losses. Various N03-N  transformation processes need to be
 calibrated as a function of tillage  system to improve model
 NAL Call No.:  290.9-Am32T
 118. Simulating tillage effects on water quality by using RZWQM.
 Singh, P.; Kanwar, R. S. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1992. (922539) 11 p. 
 Paper presented at the "1992 International Winter Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 December 15-18,  1992, Nashville, Tennessee.
 Descriptors: water-quality; tillage-; drainage-water; models-;
 pesticides-; nitrogen-; soil-water-movement; prediction-; iowa-
 NAL Call No.:  290.9-Am32P
 119. Simulation and evaluation of alternative nutrient management 
 practices on a demonstration watershed.
 Stone, K. C.; Hunt, P. G.; Coffey, S. W. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1993. (93-2572) 13 p. 
 Paper presented at the "1993 International Winter Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 December 14-17,  Chicago, Illinois.
 Descriptors: surface-water; groundwater-; plant-nutrition;
 watersheds-; catchment-hydrology; water-quality;
 simulation-models; evaluation-; crop-management; north-carolina;
 NAL Call No.:  290.9-Am32P
 120. Sludge application effects on runoff, infiltration, and
 water  quality.
 Bruggeman, A. C.; Mostaghimi, S. 
 Water-resour-bull v.29, p.15-26. (1993).
 Includes references.
 Descriptors: agricultural-soils; sewage-sludge;
 application-rates; no-tillage-; tillage-; infiltration-; runoff-;
 losses-from-soil; water-quality; virginia-; conventional-tillage
 Abstract: Land application of sewage sludge requires careful
 monitoring  because of its potential for contamination of surface
 water and ground  water. A rainfall simulator was used to
 investigate the effects of  freshly applied sludge on
 infiltration, and on runoff of sediment and  nutrients from
 agricultural crop lands. Rain was applied to 16  experimental
 field plots. A three-run sequence was used to simulate  different
 initial moisture conditions. Runoff, sediment, and nutrient 
 losses were monitored at the base of each plot during the
 simulated  rainfall events. Sludge was surface applied and
 incorporated at  conventionally-tilled plots and surface applied
 at no-till plots, at  rates of 0, 76, 150 kg-N/ha. Steady-state
 infiltrability increased as a  result of sludge application,
 although the no-till practice was more  effective in increasing
 the infiltrability than the sludge application.  No-till
 practices greatly reduced runoff, sediment, and nutrient losses 
 from the sludge treated plots, relative to the conventional
 tillage  practices. Incorporation of the sludge was effective in
 reducing  nutrient yields at the conventionally-tilled plots.
 This effect was  more pronounced during the third rainstorm, with
 wet initial  conditions. Peak loadings of nutrients appeared
 during the rainstorm  with wet initial conditions.
 NAL Call No.:  292.9-Am34
 121. Soil nitrate leaching potential indices: using a simulation
 model  as a screening system.
 Khakural, B. R.; Robert, P. C. 
 J-environ-qual v.22, p.839-845. (1993).
 Includes references.
 Descriptors: nitrate-nitrogen; leaching-; losses-from-soil;
 simulation-models; groundwater-pollution; minnesota-
 Abstract: Simulation models LEACHM-N (Leaching Estimation and
 Chemistry Model) first tested using NO3 leaching data obtained
 from lysimeter   and tile  drainage studies conducted at three
 University of Minnesota experiment  stations. Both   simulation
 models did well in simulating total  (seasonally accumulated)
 leaching loss of NO3-N   from the soil  profile. LEACHM-N was
 selected as a screening took to develop soil NO3  leaching  
 potential (NLP) ratings using soil survey information and 
 representative county weather station   data. Simulated growing
 season  total NO3-N leached from the soil profile (below 1.5 m)
 were used   as  NLP index. Crop management practices and initial
 N were kept constant.  Soil NO3 leaching   potential ratings for
 three Minnesota counties,  Redwood, Stearns, and Sherburne were
 developed  using this method. This  soil NLP rating information
 was included in the Soil Survey Information  used to plan best N  
 management schemes.
 NAL Call No.:  QH540.J6
 122. Soil, plant, animal waste & water analysis status report for
 the  United States 1988-1991.
 Plank, C. O.; Council on Soil Testing and Plant Analysis. 
 [Washington, D.C.?] : U.S. Dept. of Agriculture, Extension
 Service .
 "Compilation of the tables and writing of the report was done by
 C.  Owen Plank"--P. 2. supported by the United States Department
 of Agriculture, Extension  Service.
 Descriptors: Soils-United-States-States-Analysis-Statistics;
 Plants-United- States-States-Analysis-Statistics;
 Animal-waste-United-States-States- Analysis-Statistics;
 NAL Call No.:  aS593.P53--1992
 123. Soil tillage effects on ammonia volatilization from
 surface-applied  or injected animal slurry.
 Sommer, S. G.; Ersboll, A. K. 
 J-environ-qual v.23, p.493-498. (1994).
 Includes references.
 Descriptors: ammonia-; losses-from-soil; volatilization-;
 cattle-slurry; pig- slurry; harrowing-; air-temperature;
 wind-speed; soil-water-content; soil-water-potential;
 Abstract: Ammonia (NH3) losses from cattle (Bos sp.) and pig (Sus
 scrofa)  slurry applied to a harrowed and unworked soil were
 studied in seven  field experiments from October 1990 to December
 1991. In one experiment  slurry was directly injected into the
 soil and in six experiments  slurry was surface-applied. Ammonia
 losses mere measured with a wind  tunnel system. From directly
 injected slurry applied to a recently  harrowed soil, NH3 losses
 were 30% of the losses from an unworked soil.  Harrowing the soil
 immediately before surface application of the slurry  reduced
 losses to less than 50% of the losses from an unworked soil.  The
 accumulated NH3 loss from slurry applied in the field was
 described  with a Michaelis-Menten-like equation, showing the NH3
 loss reaction  modeled adequately as a first-order reaction. The
 effect of treatment,  soil conditions, or environmental
 conditions on NH3 loss pattern from  slurry applied in the field
 may therefore be treated statistically by  comparing the
 parameters in the Michaelis-Menten equation.
 NAL Call No.:  QH540.J6
 124. Statistical techniques for assessing water-quality effects
 of BMPs.
 Walker, J. F. 
 J-irrig-drain-eng v.120, p.334-347. (1994).
 Includes references.
 Descriptors: farm-management; watersheds-; water-quality;
 trends-; statistical- analysis; illinois-;
 NAL Call No.:  290.9-AM3Ps-IR
 125. Subsurface drip irrigation, A BMP for controlling drainage
 outflow  and reducing groundwater contamination.
 Phene, C. J.; Hutmacher, R. B.; Ayers, J. E.; Ben Asher, J. 
 Proceedings of Industrial and Agricultural Impacts on the 
 Hydrologic Environment  the Second USA/CIS Joint Conference on 
 Environmental Hydrology and Hydrogeology / USA/CIS Joint
 Conference on  Environmental Hydrology and Hydrogeology.
 Alexandria, VA : Water  Environment Federation, c1993.. v. 2 p.
 Title on cover : Environmental impact of agricultural practices
 and  agrichemicals / edited by Y. Eckstein and A. Zaporozec.
 Descriptors: vegetables-; trickle-irrigation;
 subsurface-irrigation; drainage-; groundwater-;
 groundwater-pollution; water-; salinity-; california-;
 best-management-practice; drainage-outflow-control; groundwater-
 NAL Call No.:  GB652.U82-1993
 126. Technical guidance for implementing BMPS in the Coastal
 Frederick, R. E.; Dressing, S. A. 
 Water-sci-technol v.28, p.129-135. (1993).
 Paper presented at the IAWQ First International Conference on 
 "Diffuse (Nonpoint) Pollution: Sources, Prevention, Impact,
 Abatement."  September 19-24, 1993, Chicago, Illinois.
 Descriptors: water-pollution; coastal-areas; technical-aid;
 guidelines-; pollution-; sources-; usa-;
 best-management-practices; environmental-protection-agency;
 NAL Call No.:  TD420.A1P7
 127. A test of procedures for determining the ground water
 protection  list.
 Johnson, B. R.; California Environmental Protection Agency.
 Environmental Hazards Assessment Program. 
 Sacramento, Calif. : Environmental Hazards Assessment Program, 
 State of California, Environmental Protection Agency, Dept. of 
 Pesticide Regulation, Environmental Monitoring and Pest
 Management  Branch, [1992] v, 42 p. : map.
 "August, 1992"--Cover.
 Descriptors: Groundwater-California-Sampling;
 Water-quality-California-Measurement; Wells-California
 NAL Call No.:  GB1001.72.S3T469--1992
 128. A test of procedures for determining the ground water
 protection  list : appendix to report EH 92-06.
 Johnson, B. R.; California Environmental Protection Agency.
 Environmental Hazards Assessment Program. 
 Sacramento, Calif. : Environmental Hazards Assessment Program, 
 State of California, Environmental Protection Agency, Dept. of 
 Pesticide Regulation, Environmental Monitoring and Pest
 Management  Branch, [1992] 126 p. : ill..
 Cover title.
 Descriptors: Groundwater-California-Sampling;
 Water-quality-California-Measurement; Wells-California
 NAL Call No.:  GB1001.72.S3T47--1992
 129. Tillage and ammonia banding impacts on water, N, and
 herbicide  movement : final technical report.
 Clay, S. A.;  Clay, D. E.; Geological Survey (U.S.). 
 Brookings, S.D. : Plant Science Dept., South Dakota State 
 University, [1993] vii, 49 leaves : ill..
 Cover title.
 Descriptors: Agricultural-chemicals-Environmental-aspects;
 Groundwater-flow; Tillage-Environmental-aspects;
 NAL Call No.:  TD427.A35C63--1993
 130. Tillage and furrow diking effects on water balance and
 yields of  sorghum and cotton.
 Baumhardt, R. L.; Wendt, C. W.; Keeling, J. W. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  July/Aug 1993. v. 57 (4) p. 1077-1083. 
 Includes references.
 Descriptors: sorghum-bicolor; gossypium-hirsutum; rotations-;
 deep-tillage; chiselling-; no-tillage-; dikes-; furrows-;
 water-conservation; semiarid-soils; soil-water-balance;
 crop-yield; runoff-; rain-
 Abstract: Information on the combined effects of deep or
 no-tillage together  with furrow dikes (small earthen dams
 constructed in the furrow) on  water conservation in semiarid
 regions is limited. The purpose of this  study was to compare the
 amount of rain conserved and the yields of  forage sorghum
 [Sorghum bicolor (L.) Moench] and cotton (Gossypium  hirsutum L.)
 as affected by furrow dikes and tillage for a 3-yr period.  An
 Olton clay loam (fine, mixed, thermic Aridic Paleustoll) was 
 alternately cropped to cotton and sorghum. Forage sorghum was
 grown in  (i) disk or (ii) chisel-disk tilled 16 by 23.8 m field
 plots with and  without furrow diking. Cotton was grown in
 rotation following sorghum  after (i) conventional moldboard-disk
 or (ii) no-tillage, with furrow  dikes in one-half of the tillage
 treatment plots. Crop yield, rainfall  amount, soil water
 content, and runoff of natural rainfall and of  simulated
 rainfall, applied at 80 mm h-1 for 1 h, were measured.  Compared
 with conventionally tilled undiked plots, cumulative nonponded 
 infiltration of simulated rainfall was significantly greater with
 no- tillage treatments and greater (not significant) in
 furrow-diked  treatments. Runoff of natural rainfall from plots
 with furrow dikes  averaged approximately 22 mm less than from
 undiked plots, and it was  as much as 57 mm less; however, runoff
 from diked fields was observed.  Under the conditions of this
 3-yr study, diking did not significantly  increase crop water use
 and yield, but no-tillage significantly  increased crop water use
 and yield 1 yr. We conclude that furrow dikes  installed during
 the growing season did not increase water conservation  and crop
 yields under the conditions of this 3-yr study due to seasonal 
 dike consolidation that reduced the detention capacity and to. is
 more effective than chisel tillage for increasing water
 conservation  and crop yields for the conditions of this study.
 NAL Call No.:  56.9-So3
 131. Tillage and grass filter strip effects on sediment and
 chemical  losses.
 Madison, C. E. 
 1992. xv, 155 leaves : ill..
 Includes vita and abstract.
 Descriptors: Tillage-; No-tillage-;
 Conservation-tillage-Evaluation; Agricultural-pollution
 NAL Call No.: KyU Thesis-1992-Madison
 132. Tillage and winter wheat residue management effects on water 
 infiltration and storage.
 Dao, T. H. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  Nov/Dec 1993. v. 57 (6) p. 1586-1595. 
 Includes references.
 Descriptors: triticum-aestivum; winter-wheat; soil-water-balance;
 soil-water- content; soil-water-regimes; soil-depth;
 seasonal-variation; no-tillage- ; stubble-mulching; plowing-;
 crop-residues; infiltration-; soil- density;
 hydraulic-conductivity; water-conservation; precipitation-;
 evaporation-; oklahoma-; crop-residue-management
 Abstract: In traditional winter wheat (Triticum aestivum L.)
 cropping regions  of the southern Great Plains,   production
 constraints exist because of  extreme variability in
 precipitation during planting  periods.  Intensive tillage
 aggravates dry early fall conditions to further  hamper wheat
 emergence   and growth. From 1983 through 1991, we  determined
 the effects of three tillage and residue   management  practices
 on soil water storage in Bethany (fine, mixed, thermic Pachic 
 Paleustoll) and   Renfrow (fine, mixed, thermic Udertic
 Paleustoll)  silt loams on a 2% slope near El Reno, OK. We  
 measured soil  management cumulative effects on soil bulk density
 and water  infiltration during   and after the 1990-1991 growing
 season. Every  season, no-till soil consistently had higher 
 volumetric water content  in the 0- to 1.2-m depth, except in
 late fall or early spring when    root-zone recharge took place
 for both soils. The gain was corroborated  by increased
 water-holding   capacity and decreased bulk density of no- till
 soils. Seasonal variability of field infiltration  was more 
 evident in plowed soil than in no-till soil. Such temporal
 dependence  would affect surface   distribution and flow of
 precipitation to  explain differences in runoff, soil erosion,
 and  environmental impacts  of tillage systems between October
 and June. Water infiltration into no- till   soil was
 significantly higher than into plowed soil at similar  water
 contents. Under ponding,   recharge occurred through macropores, 
 directly wetting depths of 0.4 to 0.6 m of no-till soil, in.
 implications on profile   recharge rate and solute transport in
 the  field. Therefore, elimination of inversion tillage  enhanced 
 precipitation storage, thereby alleviating detrimental effects of 
 climate variability in   annual winter wheat cultivation.
 NAL Call No.:  56.9-So3
 133. Tillage effects on agrichemical movement through the Vadose
 Wilson, G. V.; Tyler, D. D.; Storck, N. J.; Essington, M. E.;
 Mueller, T. G. 
 Tenn-farm-home-sci p.34-39. (1994).
 Includes references.
 Descriptors: soil-analysis; water-quality; macropores-;
 conservation-tillage; groundwater-; infiltration-; leachates-;
 field-tests; tennessee-
 NAL Call No.:  100-T25F
 134. Tillage effects on fate and transport of pesticides in a
 Caostal  Plain Soil. I. Surface runoff.
 Heatwole, C. D.; Zacharias, S.; Dillaha, T. A.; Mostaghimi, S. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1991. (912543) 13 p. 
 Paper presented at the "1991 International Winter Meeting
 sponsored  by The American Society of Agricultural Engineers,"
 December 17-20,  1991, Chicago, Illinois.
 Descriptors: water-quality; tillage-
 NAL Call No.:  290.9-Am32P
 135. Tillage effects on SCS runoff curve numbers.
 Yoon, K. S.; Yoo, K. H.; Soileau, J. M. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1991. (91-2615) 21 p. 
 Paper presented at the 1991 International Winter Meeting
 sponsored  by The American Society of Agricultural Engineers,
 December 17-20,  1991, Chicago, Illinois.
 Descriptors: cotton-; tillage-; probability-; runoff-; rain-;
 NAL Call No.:  290.9-Am32P
 136. Tillage studies with a corn-soybean rotation: hydrology and 
 sediment loss.
 Edwards, W. M.; Triplett, G. B.; Van Doren, D. M.; Owens, L. B.;
 Redmond, C. E.; Dick, W. A. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  July/Aug 1993. v. 57 (4) p. 1051-1055. 
 Includes references.
 Descriptors: glycine-max; zea-mays; rotations-; secale-cereale;
 cover-crops; conservation-tillage; no-tillage-; tillage-;
 runoff-; soil-; losses- from-soil; water-erosion; watersheds-;
 Abstract: When soybean [Glycine max (L.) Merr.] is produced on
 sloping fields  using conventional tillage and mechanical
 cultivation for weed control,  potential soil losses are high,
 limiting production to relatively flat  lands. With the advent of
 conservation tillage practices and herbicides  for weed control,
 soybean production with tolerable soil losses on  sloping fields
 has become technically possible. To evaluate soil loss  under
 these new conditions, runoff and erosion were measured on six 
 small watersheds that were farmed for 6 yr in a corn (Zea mays
 L.)- soybean rotation with conservation tillage. Two of the
 watersheds were  chiseled each year, two others paraplowed, and
 the other two received  no-tillage. A rye (Secale cereale L.)
 cover crop was established each  winter following soybean. With
 average yearly rainfall of 930 mm,  yearly runoff was 63.5 mm and
 varied between 28 and 108 mm. Average  yearly soil loss for the
 6-yr period was 526 kg/ha, < 10% of the  allowable soil loss. Two
 storms caused most of the erosion, with a  single storm
 accounting for 42% of the total measured soil loss.  Earlier,
 these same watersheds averaged 5750 kg/ha of measured soil  loss
 during the corn years of a corn-wheat-meadow-meadow rotation with 
 conventional tillage.
 NAL Call No.:  56.9-So3
 137. Tillage studies with a corn-soybean rotation: surface runoff 
 Owens, L. B.; Edwards, W. M. 
 Soil-Sci-Soc-Am-j. [Madison, Wis.] Soil Science Society of
 America.  July/Aug 1993. v. 57 (4) p. 1055-1060. 
 Includes references.
 Descriptors: glycine-max; zea-mays; rotations-; secale-cereale;
 cover-crops; conservation-tillage; no-tillage-; nutrients-;
 losses-from-soil; runoff- water; surface-water; nutrient-content;
 Abstract: When soybean (Glycine max (L.) Merr.] is grown on
 sloping soils,  there is a high potential for soil and nutrient
 losses. The purpose of  this study was to compare nutrient losses
 in surface runoff across a  range of watershed conditions when
 tillage practice was a variable. For  6 yr in east-central Ohio,
 nutrient concentrations and transport in  surface runoff were
 measured from six small (< 1-ha) watersheds planted  to a corn
 (Zea mays L.)-soybean rotation. Two watersheds were chisel 
 plowed each year, two were paraplowed, and two received
 no-tillage. Rye  (Secale cereale L.) provided winter cover
 following soybean harvest.  Nitrate-N and K concentrations in
 surface runoff were greater during  corn years than soybean
 years, but there was no significant difference  among tillage
 treatments. There were no consistent differences between  crops
 or among tillage practices for the transport of soluble P, 
 soluble K, and total organic C (TOC). Most of the NO3-N loss was
 in the  runoff from a small percentage of runoff events. Although
 NO3-N  concentrations in surface runoff frequently exceeded 10
 mg/L during the  corn years, the actual amount of N lost was
 small. But because of year- to-year variation in runoff, which
 masked most of the differences  resulting from cropping or
 tillage practice, there is a need for long- term research (> 6
 yr) to assess the environmental risks associated  with a
 particular management practice.
 NAL Call No.:  56.9-So3
 138. Use of an integrated transient flow and water budget
 procedure to  predict and partition components of local recharge.
 Schuh, W. M.; Klinkebiel, D. L.; Gardner, J. C. 
 J-hydrol v.148, p.27-60. (1993).
 Includes references.
 Descriptors: groundwater-recharge; water-budget; transient-flow;
 soil-water- movement; topography-; methodology-; microtopography-
 Abstract: A combined transient flow and water budget (TFWB)
 method and  accounting procedure was developed and used to
 measure and partition  the components of recharge to a sand and
 gravel aquifer underlying  about 6.0 m of glacial till overlain
 by a nearly level land surface.  The TFWB procedure was used to
 evaluate and quantify the dynamic  interaction between surface
 recharge, till water level (at 2-4 m), and  water cycling within
 the soil and vadose zone. Site-specific recharge  activity was
 highly dependent upon surface microtopography. However,  the
 homogenizing effect of the water table, measured by capillary 
 movement of water through the vadose and soil zone, substantially 
 offset the effects of surface and soil spatial variability and
 allowed  relatively uniform estimates of local recharge at
 individual  measurement sites. Substantial internal cycling of
 water within the  soil and vadose zone was caused by the
 interaction of surface  infiltration variability and water
 redistribution at the water table,  even for measurement sites
 having little direct surface recharge  activity. Through internal
 cycling, a single volume of water  originating at the surface
 frequently passed through more than one soil  and vadose profile
 during the recharge process. By applying TFWB  procedures for the
 full soil and vadose zone between the surface to the  water
 table, good estimates of local recharge to the Carrington aquifer 
 could be made for the experimental area using few measurement
 NAL Call No.:  292.8-J82
 139. Use of GIS to evaluate manure management alternatives.
 Young, S. E.; Richert, S. E.; Johnson, C.; Emenheiser, T. C. 
 Pap-Am-Soc-Agric-Eng. St. Joseph, Mich. : American Society of 
 Agricultural Engineers,. Winter 1992. (922533) 15 p. 
 Paper presented at the "1992 International Winter Meeting
 sponsored  by the American Society of Agricultural Engineers,"
 December 15-18,  1992, Nashville, Tennessee.
 Descriptors: animal-manures; models-; land-use; uptake-;
 nitrogen-; phosphorus-; crop-yield; agricultural-wastes;
 watersheds-; pennsylvania-; geographical-information-systems
 NAL Call No.:  290.9-Am32P
 140. Water quality impacts of conservation and nutrient
 management  practices in Pennsylvania.
 Hamlett, J. M.; Epp, D. J. 
 J-soil-water-conserv v.49, p.59-66. (1994).
 Includes references.
 Descriptors: water-quality; sediment-; nutrients-;
 losses-from-soil; computer- simulation; soil-management;
 environmental-management; environmental- impact; pennsylvania-;
 best-management-practices-bmp; chesapeake-bay
 NAL Call No.:  56.8-J822
 141. Water quality in mountain ash forests--separating the
 impacts of  roads from those of logging operations.
 Grayson, R. B.; Haydon, S. R.; Jayasuriya, M. D. A.; Finlayson,
 B. L. 
 J-hydrol v.150, p.459-480. (1993).
 In the special issue: Water Issues in Forests Today / edited by 
 E.M. O'Loughlin and F.X. Dunin. November 22-26, 1992, Canberra,
 Descriptors: eucalyptus-regnans; mountain-forests; water-quality;
 flow-; clearcutting-; logging-effects; regeneration-; roads-;
 usage-; maintenance-; runoff-water; sediment-yield;
 catchment-hydrology; australia-; base-flow; storm-flow
 Abstract: The purpose of the two catchment studies reported here
 was to allow  the effects on water quality of road use and
 maintenance to be  separated from the effects of a logging
 operation. In the first  project, known as the Myrtle experiment,
 two small catchments in an old- growth mountain ash (Eucalyptus
 regnans) forest were chosen for a  paired catchment study of the
 effects on physical and chemical water  quality (baseflow and
 stormflow) of logging under a strict code of  practice and with
 no roads crossing runoff producing areas. In the  second project,
 known as the Road 11 experiment, the effect on sediment 
 production from unsealed forest roads of vehicle use and level of
 road  maintenance was assessed. The Myrtle experiment showed that
 the  harvesting and regeneration operation did not have a major
 impact on  the stream physical or chemical water quality.
 Increases were detected  in turbidity, iron and suspended solids
 at baseflows, but these were  small in absolute terms and of
 similar magnitude to the measurement  error. The stormflow data
 revealed no significant influence of the  logging operation. The
 suspension of logging during wet weather, the  protection of the
 runoff producing areas with buffer strips and the  management of
 runoff from roads, snig tracks and log landing areas  eliminated
 intrusion of contaminated runoff into the streams, thereby 
 avoiding the adverse effects of logging. The Road 11 study
 determined  that annual sediment production from forest roads was
 in the range of  50-90 t of sediment per hectare of road surface
 per year, with  approximately two-thirds being suspended sediment
 and one-third coarse  material. The use of gravel reduced
 sediment production, provided a  sufficient depth of material was
 used. Increasing the level of road  maintenance with increasing
 traffic load controlled. sediment production increased by
 approximately 40%. The results  indicate that by identifying the
 areas that produce runoff it is  possible to prevent contaminated
 runoff reaching the streams. Roas, on  the other hand, produce
 large quantities of sediment, even when well  maintained, so
 careful consideration of their placement and management  is
 NAL Call No.:  292.8-J82

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