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Item No. 1 of 19

ACCESSION NO: 0084263 SUBFILE: CRIS
PROJ NO: IOW02463 AGENCY: CSREES IOW
PROJ TYPE: HATCH PROJ STATUS: TERMINATED MULTISTATE PROJ NO: NC-157
START: 01 OCT 1996 TERM: 30 SEP 2001 FY: 2001

INVESTIGATOR: Cruse, R. M.; Moore, K. J.

PERFORMING INSTITUTION:
AGRONOMY
IOWA STATE UNIVERSITY
AMES, IOWA 50011

CROP AND RUMINANT SYSTEMS TO CONSERVE MIDWESTERN UNGLACIATED SOILS AND WATER QUALITY

OBJECTIVES: Evaluate alternative forage production systems in intensive cattle management. 2) Evaluate cattle response to alternative forages. 3) Evaluate forage-grain-cattle management systems that conserve soil and water quality.

APPROACH: Kura clover will be evaluated as a living mulch for corn production. Macronutrient and soil pH requirements of cup-plant will be determined. Yield and composition of stockpiled forages and crop residues for wintering beef cows will be determined. Performance of heifers fed cup-plant will be compared with those fed alfalfa silage. Calf production, reproductive efficiency, forage selection and forage intake by beef cows grazing in year-around systems will be determined. Preferential transport of contaminants under ridge-tillage will be determined. Effects of crop rotation on soil and water quality will be evaluated. Economic analysis of alternative management-intensive grazing systems for beef cattle operations will be developed.

PROGRESS: 1996/10 TO 2001/09
The driftless region is unique and will require unique cropping and animal management systems to maintain fragile soil and water resources. Cropping system trials evaluated production potentials, and in some situations, cropping system impacts on surface runoff water quality. Strip intercropping with corn (Zea mays), soybean (Glycine max), and oat (Avena sativa) resulted in significantly higher crop yields, especially in the corn strip border positions and in oat boarder positions. Overall, total production as evaluated with the land equivalent ratio, increased when averaged across all crops. The system proved quite dynamic in production potential, and year-by-year results were dependent on weather conditions. Under favorable water conditions (adequate rainfall) corn border yields exceeded that in other positions. With a shortage of water, water competition between the small grain and corn in the border position resulted in decreased corn grain yield. Oat yield in the border position, however, was increased. Soybean yields adjacent to corn were decreased relative to strip center positions when rainfall was adequate for optimum production and increased relative to the strip center next to the oat strip. Under water stress, soybeans adjacent to the corn border position yielded comparable to the strip center (and sometimes higher), but yields next to the oat strip were decreased. Water competition between corn and oat existed in drier years, however, competition for nitrogen applied to the corn strip never occurred. Using the basal stalk nitrate test for each row of corn in the corn strip revealed significantly lower stalk nitrate concentrations existed in the border rows relative to the strip center rows. Frequently nitrate concentrations were below sufficiency levels in border rows, even though these rows exhibited the highest corn grain yields. Depleted stalk nitrates were attributed to increased nitrate demand resulting from higher yield potential and not to reduced supply. Economics of the system were compared to that for a conventional corn/soybean rotation. On a land area basis the strip intercropping system was superior. However, with this more complex system less land area could be farmed by a single farmer than if he/she managed a conventional cropping system. Sediment movement in this system as measured with rainfall simulation indicates very favorable soil conservation would result, especially when the rows/strips are planted perpendicular to the slope. Soil loss and water runoff of corn production using a kura clover cover crop was also evaluated. Final analysis of this last study is not complete. However, qualitative evaluation strongly indicates the cover crop system greatly reduced sediment movement in crop plots with slopes of approximately 8 percent.

IMPACT: 1996/10 TO 2001/09
Soil and water resources could be affected very favorably by increased adoption of either the strip intercropping system or corn production using kura clover as a perennial cover crop. This region, with steep slopes and small fields are well suited for either system. Strip intercropping would also permit soybeans to be produced in this area with much less soil and water degradation than typically occurs with conventional systems being used.

PUBLICATIONS: 1996/10 TO 2001/09
1. Ghaffarzadeh M, F Garcia Prechac and RM Cruse. 1997. Tillage Effect on Soil Water Content and Corn Yield in a Strip Intercropping System. Agron. J. 89:893-899.
2. Gilley JE, LA Kramer, RM Cruse and A Hull. 1997. Sediment movement within a strip intercropping system. J. Soil and Water Con. 52:443-447.
3. Mohammadreza G, F Garacia Prechac, RM Cruse and MM Harbur. 1998. Fertilizer and soil nitrogen use by corn and border crops in a strip intercropping system. Agron. J. 90:758-762.
4. Ellsbury MM, DN Exner and RM Cruse RM. 1999. Movement of corn rootworm larvae (Coleoptera: Chrysomelidae) between border rows of soybean and corn in a strip intercropping system. J. Econ. Entomol. 92:207-214.
5. Exner DN, DG Davidson, M Ghaffarzadeh and RM Cruse. 1999. Yields and returns from strip intercropping on six Iowa farms. Amer. J. Alternative Agric. 14(2):69-77.
6. Harbur MM, M Ghaffarzadeh and RM Cruse. 2000. Corn (Zea Mays L.) yield response to N fertilizer in conventional and alternative rotations. J. Iowa Acad. Sci. 107:42-45.
7. Wright SR, DD Buhler, KA Kohler and RM Cruse. 2000. Weed seedbanks and seedling emergence in a two and three crop narrow strip intercropping/rotation system. J. Iowa Acad. Sci. 107(1):10-15.
8. Cruse RM, R Mier and CW Mize. 2001. Surface residue effects on erosion of thawing soils. Soil Sci. Soc. Amer. J. 65:178-184.
9. Ghaffarzadeh M, F Garcia Prechac, RM Cruse and MM Harbur. 2001. Tillage effect on soil water content and soybean yields in a strip intercropping system. J. Iowa Acad. Sci. 108:19-23.
10. Exner DN and RM Cruse. 2001. Profitability of crop rotations in Iowa in a stress environment. J. Iowa Acad. Sci. Accepted.
11. Brummer EC and KJ Moore. 2001. A simple method to increase alfalfa yields in the establishment year. p. 21-22. IN Leopold Center Progress Report, Volume 10, Leopold Center for Sustainable Agriculture, Ames, IA.
12. Harmoney KR, KJ Moore, EC Brummer, CL Burras and JR George. 2001. Spatial legume composition and diversity across seeded landscapes. Agron. J. 93:992-1000.
13. Mitchell RB, DD Redfearn, LE Moser, KJ Moore, RJ Grant and BH Kirch. 1998. Tiller demographics and leaf area index of four perennial grasses. Agron. J. 90:47-53.

PROJECT CONTACT:

Name: Good, C.
Phone: 515-294-4544
Fax: 515-294-2909
Email: cgood@iastate.edu

Item No. 2 of 19

ACCESSION NO: 0156208 SUBFILE: CRIS
PROJ NO: MO-FESL0257 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: REVISED
START: 01 JUL 2000 TERM: 30 JUN 2005 FY: 2001

INVESTIGATOR: Thompson, A. L.

PERFORMING INSTITUTION:
FOOD SCIENCE & ENGINEERING
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

WATER QUALITY, EROSION, AND WATER MANAGEMENT

OBJECTIVES: Investigate combined effects of water droplet energy and application rate on soil detachment, infiltration, and resulting chemical movement on unprotected and protected soils for both physical and chemical amendments; Develop, evaluate, and revise computer models for assessing productivity of soils under natural and artificially eroded conditions, and revise computer models for assessing water management under field conditions for moving sprinkler systems; Investigate the solids movement and treatment within submerged flow (SF) constructed wetlands, and relate these to relationships between media diameter and porosity as functions of wetland and plant maturity (root diameter and biomass development) of a rock-bed constructed wetland for use in designing effective SF systems.

APPROACH: Experiments will be conducted in the laboratory using a multi-droplet rainfall simulator producing rainfall characteristics approximating natural conditions for kinetic energy and droplet size in relation to rainfall intensity. Soils placed in beds 0.3 m x 1 m will be exposed to rainfall, both with and without surface residue protection, to evaluate erosion and chemical movement on the surface and through the profile. Data from field soils eroded naturally and artificially (scalped) will be assessed on the basis of crop production and response to irrigation and fertility using various crop production models. Comparisons will be made over years for differing rainfall conditions. Irrigation water management strategies for moving sprinkler systems will be evaluated on the basis of application efficiency and uniformity for impact sprinklers and various spray devices. The DPEVAP computer model, validated from field measurements, will be used to quantify these parameters. Simplified management models will be developed on the basis of these results. Data from six submerged flow, rock bed wetland flumes (3 m x 1 m x 0.3 m) will be used to evaluate solids (TSS and TVS) movement and treatment in beds with and without plants. Models will be developed on the basis of these results for predicting solids buildup with wetland maturity for domestic waste water treatment.

NON-TECHNICAL SUMMARY: Environmental response to water management for crop production and domestic water uses impacts the quality of life. This research is focused on improving water management to reduce adverse environmental impact while maintaining acceptable production and water availability. Cooperating states include Nebraska.

PROGRESS: 2001/01 TO 2001/12
The effects of polyacrylamide (PAM) on infiltration, runoff, and erosion was quantified for a claypan soil as a function of rainfall kinetic energy. A laboratory study was conducted using a stationary rainfall simulator and bare-surfaced soil beds of 1m x 0.3m x 0.3m on a 4% bedslope. Drop size distribution was similar to natural rainfall when falling at 6.4 cm-1. Fall height was 7.1 m, therefore impact velocity for droplets greater than 2 mm diameter was less than terminal. Treatments included 0, 2.47, and 9.88 kg ha-1 of PAM application rates. Total rainfall kinetic energy that could be applied before runoff initiation increased nearly 50% with 9.88 kg ha-1 of surface applied PAM compared to a bare soil with no PAM. Infiltration depth prior to runoff increased at a rate of 0.07 cm of water for each kg of PAM applied. Runoff depth was greatest for the bare soil with no PAM. Total sediment loss decreased by 10 and 31% with a PAM application of 2.47 and 9.88 kg ha-1, respectively. Eight different irrigation scheduling methods were compared based on ease of use and cost. These methods were applied on field plots of cotton and soybean. Three replicates were used for each treatment for a silt loam soil. Plots were 9.1m x 7.6m with row spacings of 0.76 m. The computer based method using readily available data, the irrigation chart method, and evaporation pan required the least amount of in-season labor. Tensiometer and gypsum block methods required the greatest in-season labor. Scheduling methods using infrared sensors were useful but refinements in procedures are needed for irrigators. The Hydrological Simulation Program - FORTRAN (HSPF) version 11.0 was applied to Goodwater Creek watershed, a 72 km2 claypan agricultural watershed located in central Missouri. Key hydrologic and sediment parameters were calibrated using data collected in two different years from the watershed and a 36 ha field enclosed in the watershed. Predicted stream flow was 2.8% lower than measured, and 84, 2, and 14% of the predicted stream flow was contributed by surface, interflow, and groundwater, respectively. The model under-predicted for large storm events and over-predicted for small events that occurred after long dry periods when soil cracking was dominant. The model over-predicted for dry years where measured runoff was less than 300 mm and under-predicted for wet years where measured runoff was greater than 300 mm. Predicted total sediment losses were 9 and 17% higher than those measured from the field and watershed, respectively. Most of the sediment yield over-prediction occurred during the months with large runoff events.

IMPACT: 2001/01 TO 2001/12
Surface application of PAM at rates up to 9.88 kg ha-1 can be effective in reducing the time to initiate runoff, total runoff volume, and total sediment transport for a bare, unprotected soil. Irrigation scheduling methods such as irrigation charts and evaporation tubs are more likely to be adopted by irrigators. The HSPF model is useful for long-term runoff and sediment prediction but tends to underestimate large and overestimate small events.

PUBLICATIONS: 2001/01 TO 2001/12
1. Thompson, A.L., F. Ghidey, T.P. Regmi. 2001. Raindrop energy effects on chemical and sediment transport. Transactions of ASAE, Vol. 44(4):835-841.
2. Ghidey, F., A.T. Hjelmfelt, A.L. Thompson, J.O. Duru, and M. Wang. 2002. Evaluating HSPF for simulating hydrology and sediment yield from a claypan agricultural watershed. AWRA (in press).
3. Thompson, A.L. T.P. Regmi, and F. Ghidey. 2001. Influence of kinetic energy on infiltration and erosion. p. 151-154. In J.C. Ascough II, D.C. Flanagan (ed.) Soil Erosion Research for the 21st Century. Proc., Honolulu, HI, Jan. 3-5, 2001. ASAE, St. Joseph, MI.
4. Thompson, A.L., F. Ghidey, and E.E. Alberts. 2001 Effect of polyacrylamide on erosion for various rainfall kinetic energies, ASAE 94th International Meeting, Pap. no. 01-2153, Jul 29-Aug 1, Sacramento, CA.
5. Bockhold, D.L., J.C. Henggeler, K.A. Sudduth, and A.L. Thompson. 2001. Comparison of eight irrigation scheduling tools on soybean and cotton. In Irrigation Association, Arlington, VA (ed). Proc. 22nd Annual International Irrigation Show & Conf. Oct 31-Nov 6, San Antonio, TX, p. 117-123.

PROJECT CONTACT:

Name: Thompson, A. L.
Phone: 573-882-4004
Fax: 573-882-1115
Email: thompsona@missouri.edu

Item No. 3 of 19

ACCESSION NO: 0156347 SUBFILE: CRIS
PROJ NO: MO-FESL0281 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: EXTENDED
START: 01 OCT 1997 TERM: 30 SEP 2003 FY: 2001

INVESTIGATOR: Borgelt, S. C.

PERFORMING INSTITUTION:
FOOD SCIENCE & ENGINEERING
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

TECHNOLOGY FOR EFFICIENT USE OF AGRI-RESOURCES

OBJECTIVES: 1. To quantify and analyze spatial variability. 2. To develop innovative renewable farming systems that are more sustainable. 3. To assess and evaluate educational strategies and methods.

APPROACH: Laboratory and field investigations will take place to develop techniques for practical spatial data interpolation, the development of nutrient management plans using spatial data collected through time, and develop integrated farming systems that are more sustainable. Additionally, educational programs and evaluation methods will be developed and tested.

PROGRESS: 2001/01 TO 2001/12
In the past, a protoype optical granular fertilizer sensor was designed and lab tested that showed excellent static and dynamic results. However, the granular sensor was quite complex and costly. New pressure sensing techniques for monitoring and measuring granular fertilizer are being developed and tested.

IMPACT: 2001/01 TO 2001/12
Variable-rate application of crop chemicals inputs will help optimize crop production inputs. Precision farming techniques will help producers maximize profit while being good environmental stewards.

PUBLICATIONS: 2001/01 TO 2001/12
No publications reported this period


Item No. 4 of 19

ACCESSION NO: 0189296 SUBFILE: CRIS
PROJ NO: MO-NRRB0185 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: NEW MULTISTATE PROJ NO: NC-230
START: 01 OCT 2000 TERM: 30 SEP 2005

INVESTIGATOR: Hammer, R. D.; Dwyer, J. P.; Hodge, S. S.; Nilon, C. H.

PERFORMING INSTITUTION:
SCHOOL OF NATURAL RESOURCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

INTEGRATING BIOPHYSICAL FUNCTIONS OF RIPARIAN SYSTEMS WITH MANAGEMENT PRACTICES AND POLICIES

OBJECTIVES: 1. Assess biophysical functions of riparian management as they relate to management practices for increasing or sustaining on-site and downstream water quality. 2. Evaluate alternative riparian management systems in terms of cost effectiveness, water quality benefits, and adoption by land managers. 3. Develop integrated tools needed for land management and policy development, to select and enhance adoption of preferred riparian management systems.

APPROACH: Two areas of primary interest will be investigated at the University of Missouri. First will be riparian buffers adjacent to streams in agricultural or forest settings. Second will be riparian corridors in urban settings. The first topic will be investigated, funding permitting, adjacent to the Missouri River on Overton Bottoms. The approach will be to establish several vegetation communities between the river channel and a new Corps of Engineers levee to be built approximate 500 meters from the channel. Proposed vegetation communities include native warm season grasses, and a variety of early successional woody communities including cottonwood, willow and ash at different densities. We will characterize soil conditions prior to vegetation establishment. Soil attributes will include surface texture, organic matter content and nutrient concentrations. We will investigate sedimentation over several years as functions of vegetation communities and flood duration. Sediments will be analyzed to determine texture, organic matter and nutrient concentrations. On a separate location on the floodplain, where water is permitted to overflow the banks with no levee present, will will conduct a similar study in two sites -- one composed of Johnson grass and a second with a mixture of native hardwoods with an understory of cool season grasses and forbes. We will quantify baseline soil attributes and monitor the changes over time after annual flooding events. The urban study will focus on the effects of storm water runoff through forested and grassed buffer strips. We have observed several locations where accelerated gully erosion occurs as a consequence of channelized surface flow from storm water pipes. We will monitor rates of gully erosion and correlate storm water quantity with site rainfall. We have installed tipping bucket rain gages on several sites, and are monitoring gully development by two procedures. We run detailed transects at right angles to the gullies so we can monitor width and depth erosion over time, and we establish transects along the flow thalwegs. This allows us to determine how the gullies develop in landscapes with layered parent materials. We have established a control plot on a wooded tract that will be subject to urban building for a subdivision, and this will be our baseline information.

NON-TECHNICAL SUMMARY: The project investigates abilities of vegetation to trap sediments and nutrients on a Missouri River floodplain under two conditions. The first is vegetational communities between the river and a levee. The second is with no levee. The second portion of the study investigates gully erosion through buffer strips as a consequence of storm water runoff in an urban setting.

PROJECT CONTACT:

Name: Hammer, R. D.
Phone: 573-882-0614
Email: hammerr@missouri.edu

Item No. 5 of 19

ACCESSION NO: 0182162 SUBFILE: CRIS
PROJ NO: MO-NRRB0326 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: NEW MULTISTATE PROJ NO: NC-174
START: 01 OCT 1998 TERM: 30 SEP 2003 FY: 2001

INVESTIGATOR: Miles, R. J.

PERFORMING INSTITUTION:
SCHOOL OF NATURAL RESOURCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

MANAGEMENT OF ERODED SOILS FOR ENHANCEMENT OF PRODUCTIVITY AND ENVIRONMENTAL QUALITY

OBJECTIVES: Assess management effects on eroded soil productivity and quality of soil, air and water resources.

APPROACH: Crop yield data and management inputs (primarily soil fertility along with organic amendments in the form of manure and tillage) from various plots and treatments on historic Sanborn Field will be utilized to assess management effects on soil productivity with some degree of erosion. These long-term data will be utilized to ascertain the influence of management on soil and water quality. The roductivity-Index model will be utilized as a basis to interpret the influence of management on the soil resource and long-term productivity.

NON-TECHNICAL SUMMARY: Long term cultivation of agricultural land has, in many instances, led to increased erosion and physical degradation thus leading to decreased crop yields. This research will assess the influence of management inputs on long-term productivity as well as soil and water quality.

PROGRESS: 1999/01 TO 1999/12
Soil erosion is strongly influenced by landscape position and soil management. Two projects on Historical Sanborn Field (the third oldest continuous research field in the world)are assessing the influence of past erosion and past soil management on soil properties and soil productivity. The first study involves the presence and persistence of Soybean Cyst Nematode (SCN) in present day and historical archived samples. The initial pilot study found greater numbers of eggs per 250 cc of soil in continous soybean than in a 3 year rotation of corn-soybean-wheat (with red clover). Within treatments for the 3 year rotation lack of K fertilization produced the greatest number of SCN eggs per 250cc of soil. The second study is assessing the use of soil electrical conductivity (EC) to delineate the spatial distribution of depth of topsoil to productivity through the Productivity Index (PI). A Geonics EM-38 meter was used to measure the apparent soil EC at core sample sites. Soil EC measurements were taken in the horizontal mode at 0 cm and 75 cm height and in the vertical mode at 0 cm and 50 cm. A soil PI was developed for each core based on the soil's bulk density, plant available water, and salt pH. Variations to soil EC measurements were significantly related to the soil PI. A regression found a combination of EC meter positions best explained the soil PI (vertical modes of 0 and 50 cm and horizontal mode of 75cm, R2=0.60).

IMPACT: 1999/01 TO 1999/12
Cyst Nematode (SCN) has been found to reduce the yield of soybeans. Little is known about persistence and management practices which influence the SCN numbers. Utilization of historical soil samples can aid in delineating crop management (monocultures vs. crop rotations)and soil fertility factors which influence persitence and subsequent damage. Additionally, use of new technology, through less intrusive methods such as electical conductivity devises may provide a quick relatively accurate measurement which can produce a quick estimate of soil productivity.

PUBLICATIONS: 1999/01 TO 1999/12
No publications reported this period

PROJECT CONTACT:

Name: Miles, R. J.
Phone: 573-882-6607
Email: milesr@missouri.edu

Item No. 6 of 19

ACCESSION NO: 0155990 SUBFILE: CRIS
PROJ NO: MO-NRSL0118 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 JUL 1994 TERM: 31 DEC 1998 FY: 1999

INVESTIGATOR: Brown, J. R.

PERFORMING INSTITUTION:
SCHOOL OF NATURAL RESOURCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

SOIL FERTILITY, PLANT NUTRITION AND NUTRIENT MANAGEMENT IN CROPPING SYSTEMS

OBJECTIVES: 1. Analyze data accumulated from prior research on micronutrients, forage fertility, biosolids and long-term soil management studies followed by the writing of the appropriate journal papers, bulletins, and internal reports. 2. Continue the long-term study entitled Sanborn Field which attempts to integrate crop management and soil amendments with the goal of documenting long-term changes in soil properties. 3. Provide the nutrient management expertise in cooperative projects on managed intensive grazing, land application of biosolids and manures, no-till crop culture, and extension soil testing programs. 4. Complete the evaluations of techniques for estimating the requirement of acid soils for liming materials and implement the new procedures into the soil testing program. 5. Cooperate with field staff, USDA-SCS, US-EPA, and Missouri DNR in developing a state nutrient management plan. 6. Represent the Missouri Agricultural Experiment Station on appropriate regional and national committees dealing with nutrient and manure management, biosolids, and soil testing.

APPROACH: There will be few unique approaches as there is sufficient software to accomplish data analysis by SAS and other standard methods. The Sanborn Field plan has been approved by the oversight committee and has been in operation since 1990. Systematic sampling plans are used in studying nutrient cycling on intensively grazed studies. Appropriate evaluation for spatial variability will be conducted using soil cores to 120 cm with backfilling with bentonite clay.

PROGRESS: 1994/07 TO 1998/12
FY1998 was used to phase out portions of this project pending the retirement of the project leader. The Sanborn Field portion of the project was transferred to Dr. R. J. Miles effective with the start of FY99. A tillage x nitrogen project utilizing a Zea maize-Glycine max rotation was terminated in Fall 1998. The principle finding was that on the claypan site the moldboard plow treatments had greater yields that no-till plots at a given N treatment. The reasons were that the no-till system had not been in place for sufficient time to establish the unique attributes of the system and spring weather in the second and third years of the study were so wet that planting , germination and denitrification problems were encountered. The fall plowed plots were better drained which provided better aeration at seeding time. Sanborn Field, in its 110th year of continuous operation, produced record Zea maize yields on the well fertilized plots.

PUBLICATIONS: 1994/07 TO 1998/12
1. Rassmussen, P. E., K. W. T. Goulding, J. R. Brown, P. R. Grace, H. H. Janzen, and M. Korschiens. 1998. Long-term agroecosystem experiments: Assessing agricultural sustainability and global change. Science 282:893-896.
2. Huggins, D. R., G. A. Buyanovsky, G. H. Wagner, J. R. Brown, R. G. Darmody, T. R. Peck, G. W. Lesoing, M. B. Vanotti and L. G. Bundy. 1998. Soil organic C in the tallgrass prairie-derived region of the corn belt: effects of long-term crop management. Soil and Tillage research 47:219-234


Item No. 7 of 19

ACCESSION NO: 0156206 SUBFILE: CRIS
PROJ NO: MO-NRSL0260 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: REVISED
START: 01 SEP 2000 TERM: 31 AUG 2005 FY: 2001

INVESTIGATOR: Gantzer, C. J.

PERFORMING INSTITUTION:
SCHOOL OF NATURAL RESOURCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

SOIL AND WATER CONSERVATION: MAINTAINING A QUALITY ENVIRONMENT WITH SUSTAINABLE AGRICULTURE

OBJECTIVES: 1) To evaluate the effectiveness of grass barriers as a soil conservation practice for Missouri to control concentrated-flow erosion in vegetative filter strips by reducing runoff velocity and promoting sediment deposition up-slope of the grass barrier. 2) To use grass barriers to assist native-species vegetative filter strips in controlling sheet erosion. 3) To demonstrate the benefit of using grass barriers with grass waterways to reduce the flow of runoff and reduce the transport of NPS pollutants reaching surface waters. 4) To enhance soil quality when used with native-species vegetative filter strips by promoting deep rooting of native plants. 5) To develop an inexpensive ratiometric piezometer sensor for an automated piezometer system. To evaluate the residual binding effects of roots on interrill erodibility. 6) To study crop and tillage effect on erosion and runoff data for the McCredie rainfall erosion plot and explore relationships exists between average Ksat and runoff from USLE runoff plots. 7) To develop an improved soil erosion estimates using de-trended rainfall erosivity for Missouri. 8) To calculate soil erosion R-factors Panama. 9) To improve corn and soybean yield prediction relative to soil productivity and weather for over a period from 1983?1993. 10) To improve quantification of soil structure using methods of computed tomography of intact soil cores and thin sections to study structural pattern.

APPROACH: Switchgrass will be planted in plots to study grass barriers used for control of concentrated flow. Grass barriers will be studied for improved edge of field sediment, and chemical trapping, immobilization and bio-degradation to promote biological improvements in soil to enhance soil quality. Simulated and natural rainfall studies will be employed. Runoff will be measured and analyzed for quantity, sediment, and dissolved N and P. Work on ratiometric piezometers will be done with lab and field tests. Sensors will be built and calibrated. Units will be installed in the field. Data will be collected and compared with "high-end" electronic piezometers for their performance. To evaluate the effect of roots on interrill erosion, data from soil from a long-term field of bromegrass on a Mexico silt loam will be used. Above ground plant-material was removed and plots were tilled using conventional field cultivation. Check plots with continuous cultivation were also initiated. Measurements related to plant material will be analyzed. Measurements of related soil physical properties will be analyzed and related to plant material. Weather station and runoff data from the McCredie Midwest Claypan Exp. Fm. will be used. Data will also be collected for stations in MO, IL, IA, KS, and NB. Time series of annual precipitation for Columbia and Power Spectral analysis will be applied to examine variation. Calibration of calculated RUSLE rainfall and EI values with estimated EI for Kingdom City MO and measured EI vs. predicted EI will be done. Hourly precipitation from weather stations in Panama will be obtained. Data also include daily maximum 60-min rainfall and the time when it occurred. Hourly rainfall data and 60-min maximum rainfall intensity will be collected to calculate the I(30) and total kinetic energy of rainfall. The procedure will allow calculation of 22-yr period to obtain R-factors. Data from an experiment located at the UMC South Farm will be analyzed to show the effect of depth of topsoil on corn and soybean growth and development. Replicated plots with four topsoil depths will be analyzed. Plots are split into high or low fertility, and split into rainfed or irrigated culture. Soil properties measured include horizon thickness, bulk density, available water, organic matter, pH, hydraulic conductivity, particle size, and fertility. Plant measurements included planting rate and date, emergence, silking or flowering, and yield. Yields will be compared to historical yield data from Sanborn Field to correlate the temporal variations in plant growth with those of weather. Use of the Productivity Index will be done. To quantify soil structure, description of bulk density, water content, and pore size distribution and continuity, use of x-ray CT imaging of intact soil cores and Thin-Sections from cores will be pursed. Samples from cultivated fields under different tillage management and from CRP, and Prairies with similar surface texture will be compared. Fractal analysis and image recognition will be used to characterize soil structure.

NON-TECHNICAL SUMMARY: Excessive erosion on croplands and subsequent water pollution is a problem. This work is to improve soil and water conservation, erosion prediction, soil and water quality, and soil structure. This will aid producers in conservation of cropland.

PROGRESS: 2001/01 TO 2001/12
A study was done to compare soils under conventional and no-tillage systems using X-ray computed tomography (CT). Chisel-disk-disk (CDD) conventional tillage and no-tillage (NT) systems were compared for a Mexico silt loam (fine, smectitic, mesic Aeric Vertic Epiaqualfs) soil. Five replicate soil cores (75-mm long by 75-mm diam.) were collected from each treatment. Two CT systems were used in this study: a medical CT scanner (MCT, 1-mm thick scans) and an ultra-high resolution CT scanner (UHCT, 0.1-mm thick scans). Significantly higher soil density was found for the NT treatment using the medical CT scanner, (P=0.05). Data from the ultra-high resolution CT scanner were used to compare the effects of scan thickness and to evaluate macropore characteristics. Macropore area was significantly higher (P<0.001) for CDD as compared to the NT treatment: 11 vs. 5%. The number of macropores in the CDD treatment were twice those in NT; their perimeter was 62% longer; and their circularity was 94% of that for pores from the NT tillage treatment. The macropore box-counting fractal dimension (D) was significantly greater (P<0.001) for CDD (D =1.44) as compared to the NT treatment (D=1.26), reflecting the greater space-filling behavior of the CDD treatment. This study shows that the ultra-high resolution CT scanner can characterize differences in soil macroporosity more precisely than standard medical CT-scanners. The use of ultra-high resolution CT tomography can aid in the discrimination of differences between seedbeds created by different tillage systems. A study evaluated the Ksat of in situ monoliths and intact cores and compared the results with other studies for Missouri claypan soils. These Ksat values were used as runoff-model inputs to assess the impact of Ksat variation on simulated runoff. Lateral in situ Ksat of the topsoil was determined on 250 by 500 by 230 mm deep monoliths. These values were compared with the Ksat of 76 by 76 mm diam. intact cores with and without bentonite to seal macropores. Mean (+/- SD) lateral in situ Ksat was 72 +/- 0.7 mm h-1 and mean intact core Ksat without bentonite was 312 +/- 58 mm h-1. The mean intact core Ksat without bentonite was significantly larger than the lateral in situ Ksat (P = 0.03). The lateral in situ Ksat was not different from core Ksat with bentonite (71 +/- 1.1 mm h-1). The intact core Ksat with bentonite differed from previous studies by 10 times. This was attributed to the variations in soil depth to claypan, macropore presence, and methodology. The impact of using an effective hydraulic conductivity (Keff) computed from measured Ksat on intact cores without bentonite underestimated the Water Erosion Prediction Project (WEPP) simulated runoff by 28% for a measured runoff event of 40 mm. The core Ksat with bentonite was correlated with measured runoff from long-term erosion-runoff plots.

IMPACT: 2001/01 TO 2001/12
A study using X-ray computed tomography (CT) to compare soil structure shows that the ultra-high resolution CT scanner can characterize differences in soil macroporosity more precisely than standard medical CT-scanners. The use of ultra-high resolution CT tomography can aid in the discrimination of differences between seedbeds created by different tillage systems. Results of hydraulic conductivity testing show that Ksat has a great impact on runoff prediction. Previously collected Ksat data cited above all under-predicted runoff when compared to measured values. The Ksat data determined on small soil cores with bentonite predicted runoff satisfactorily, indicating that the use of bentonite to plug macropores is advisable. The core Ksat values with bentonite were not significantly different from in situ Ksat values because the by-pass flow through the visible pores (>1 mm diam.) in the small cores was eliminated. A project objective is to reduce NPS pollutants and to improve water and soil quality for Missouri while improving wildlife habitat. Reporting of new information on ways to reduce NPS pollution to streams using stiff-stem grass barriers will be a major contribution. Current guidelines for vegetative filter-strips call for a minimum of 30-ft of corridor to control sediment for lands that have "uniform flow." Much of Missouri land has riparian land with concentrated (by-pass) flow. Information on the effectiveness of grass barriers will help solve this problem. Grass barriers will provide an additional way to usekeep sediments from streams.

PUBLICATIONS: 2001/01 TO 2001/12
1. Zhu, J.C., C.J. Gantzer, S.H. Anderson, R.L. Peyton and E.E. Alberts. 2001. Comparison of concentrated-flow detachment equations for low shear stress. Soil And Tillage Res. 61:203-212.
2. Gantzer, Clark J. and Stephen H. Anderson. 2002. Computed Tomographic measurement of macroporosity in chisel-disk and no-tillage seedbeds. Soil And Tillage Res. 62101-111.
3. Cheng, Z, S.H. Anderson, C.J. Gantzer, and Y. Chu. 2002. Fuzzy logic for predicting soil hydraulic conductivity using CT images. In C. Dagli (ed.) Smart Engineering System Design: Neural networks, fuzzy logic, evolutionary programming, data mining and complex systems. Vol. 11:307-312. ASME Press. N.Y.
4. Blanco-Canqui, Humberto, Clark J. Gantzer, Stephen H. Anderson, and E.E. Alberts. 2002. Tillage and Crop Influences on Saturated Hydraulic Conductivity and Runoff of a Mexico claypan soil. Soil Sci. Soc. Am. J. 66:xxx-xxx. (in press)
5. Anderson, S.H., H. Wang, R.L. Peyton, and C.J. Gantzer. 2001. Simulation of 3-D Chemical Transport in Heterogeneous Soil Cores using X-ray CT. European Union of Geosciences XI, Journal of Conference Abstracts 6(1) 780. Cambridge Publications.
6. Anderson, S.H., H.V. Kazemi, and C.J. Gantzer. 2001. Spatial Variability of Bromide and Atrazine Leaching in an Alluvial Soil. Agron. Abstracts.
7. Cheng, Z., S.H. Anderson C.J. Gantzer Y. Chu. 2001. Fuzzy logic for predicting soil hydraulic conductivity using CT images. Annie Conference. St. Louis, MO.
8. Baffaut Claire, Clark Gantzer, and Allen Thompson. 2001. Impacts of Precipitation Trends on Sediment and Chemical Yields Aug 2001. Annual Meetings of the Soil and Water Conservation Soc of Amer. Abst.
9. Anderson, S.H, C.J. Gantzer and Z. Cheng. "Determination of Soil Hydraulic Conductivity with MRB Signatures from X-ray CT Scan Images" "CT measurement of macroporosity in seedbeds using topological analysis" 17th World Congress of Soil Science which will be held during 14-21 August 2002 in Bangkok.

PROJECT CONTACT:

Name: Gantzer, C. J.
Phone: 573-882-0611
Fax: 573-884-5070
Email: gantzerc@missouri.edu

Item No. 8 of 19

ACCESSION NO: 0185771 SUBFILE: CRIS
PROJ NO: MO-NRSL0584 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: NEW
START: 01 JUL 2000 TERM: 30 JUN 2005 FY: 2001

INVESTIGATOR: Motavalli, P. P.

PERFORMING INSTITUTION:
SCHOOL OF NATURAL RESOURCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

CARBON AND NUTRIENT CYCLING IN NATURAL AND MANAGED ECOSYSTEMS WITH SOIL PHYSICAL RESTRICTIONS

OBJECTIVES: The objectives of this project are: (1) to characterize C, N and P dynamics in soils with soil physical restrictions and the influence of those dynamics on soil quality; (2) to determine the interactive effects of soil pore characteristics, hydrological properties, and soil microbial activity on C and N transformations including gaseous flux of CO2 and N2O; (3) to examine low-cost methods to evaluate soil physical restrictions and possibly incorporate these methods into routine soil testing; and (4) to evaluate and model the impact of land use management on soil C, N and P pools.

APPROACH: Several laboratory and field experiments are proposed that will evaluate the interaction of soil physical properties and moisture on nutrient transformations and availability for plant growth. The proposed laboratory studies will utilize innovative analytical methods including X-ray computed tomography (CT) for determining soil pore characteristics, the BIOLOG System for detecting changes in microbial diversity, and several physical, chemical and biological methods for fractionating soil organic C and N. Field experimentation will utilize existing long-term sites as well as establishment of new sites in several regions of Missouri where natural restrictive root zones are located.

NON-TECHNICAL SUMMARY: Induced root restricting zones, such as caused by soil compaction, have become an increasing problem for farmers in Missouri due to increasing use of heavier field equipment. This project will determine how root restricting zones affect plant nutrient availability. The results of these experiments will be used to develop methods to adjust nutrient recommendations and to identify appropriate nutrient management practices.

PROGRESS: 2001/01 TO 2001/12
Field experiments designed to determine the effects of soil compaction on nitrogen availability to corn were continued during the 2001 growing season at the Bradford Agronomy Center in North Central Missouri and at the Delta Center in Southeastern Missouri. At the Bradford Center, treatments consisted of four rates of turkey litter (0, 9, 18, and 30 Mg/ha (dry wt basis)) at two levels of surface compaction arranged in a randomized complete block design with 4 replications. In 2001, additional treatments of ammonium nitrate fertilizer (0, 84, 140, 196, and 280 kg N/ha) were applied. Treatment effects on soil bulk density, hydraulic conductivity, soil pore distribution, penetrometer resistance, soil carbon dioxide flux and soil inorganic nitrogen were monitored periodically over the growing season. Surface compaction significantly increased soil cone penetrometer resistance to a depth of 20 cm. Corn grain yields were not significantly affected by compaction possibly due to the relatively high cumulative amount of precipitation during the growing season. A significant increasing response to applied N in the turkey litter and from N fertilizer was observed. At the Delta Center, treatments were comprised of four rates of poultry litter (0, 6, 10, and 20 Mg/ha (dry wt basis)) at three levels of subsoil compaction. A subsoiling treatment to a depth of 30 cm was also included in a randomized complete block design with 4 replications. Corn grain yields were significantly higher in the subsoiled treatment compared to the compacted treatments. Yields also were significantly higher than the control treatment with the addition of poultry litter in the non-compacted and subsoiled treatments but no response to N fertilizer was observed in the compacted treatments. Field observations at the Delta Center indicated that subsoiling increased soil moisture availability and subsequently N uptake, possibly due to the break up of a naturally dense subsoil horizon.

IMPACT: 2001/01 TO 2001/12
The results of these experiments will provide for a better understanding of how to improve the nitrogen efficiency of applied animal manure and nitrogen fertilizer with different levels and types (surface or subsoil) of soil compaction. One objective is to evaluate the use of simple measurements of soil physical properties to adjust N fertilizer recommendations. The research will also help in determining the economic cost of compaction induced by field operations and loss of yields.

PUBLICATIONS: 2001/01 TO 2001/12
1. Motavalli, P.P., S.H. Anderson, R.J. Kremer, W.E. Stevens and D. Dunn. 2001. Effects of surface and subsoil compaction on nitrogen availability and carbon transformations. Agron. Abstr., American Society of Agronomy, Madison, WI.
2. Birmingham, K.A., W.E. Stevens, D.J. Dunn, and P.P. Motavalli. 2001. Effects of mechanical soil compaction on soybean growth and grain yields. Agron. Abstr., American Society of Agronomy, Madison, WI.

PROJECT CONTACT:

Name: Motavalli, P. P.
Phone: 573-884-3212
Fax: 573-884-5070
Email: motavallip@missouri.edu

Item No. 9 of 19

ACCESSION NO: 0155543 SUBFILE: CRIS
PROJ NO: MO-PSSL0099 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 JUL 1994 TERM: 31 DEC 2000 FY: 2001

INVESTIGATOR: Wiebold, W. J.

PERFORMING INSTITUTION:
PLANT SCIENCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

APPLICATION OF PRECISION AGRICULTURE TO SOYBEAN MANAGEMENT

OBJECTIVES: The overall objective is to quantify and use site-specific soil and field characteristics to improve the understanding of in-field variability for soybean health, grain quality, and yield. A large portion of this research effort is funded through two grants form the North Central Soybean Research Program. Each of these two grant proposals contains specific objective and procedures information, which will not be repeated here. These two projects involve five states in addition to Missouri (lead state). Specific objectives for work not included as part of these two research efforts are: 1. Quantify spatial variability of economically important soybean grain components including protein and fatty acid profiles. 2. Determine the relationship between soil/landscape characteristics and soybean grain composition. 3. Use surrogate measurements of soil/landscape characteristics to predict soybean grain composition. 4. Provide training and support to facilitate best management decisions by crop producers and their advisors interested in enhancing soybean grain value.

APPROACH: Data will be collected from a minimum of two fields in Missouri. These fields are part of the six-state research effort already have an extensive spatial database established in previous and current studies. Soil Electrical Conductivity (EC): Fields will be surveyed with both the Veris 3100 and the Geonics EM-38 systems. Soil profile characterization: Soil cores will be removed during EC surveys for soil characterization. Digital Elevation Model (DEM): Fields will be surveyed to obtain high accuracy elevation data with a fine vertical resolution using a Real Time Kinematic (RTK) GPS system. Soil strength: Soil strength or penetration resistance will be measured to identify potential zones of soil compaction that could affect crop rooting. Soil fertility maps: Soil fertility maps will be created for fields at least once during the study. The maps will be created using geostatistics techniques and will be based on grid soil sampling surveys of at least one sampling point per acre. Soil samples will be analyzed for the following properties: organic matter, pH, phosphorus, potassium, and cation exchange capacity. Remotely Sensed Images: Aerial images will be obtained for the Centralia field with multi-spectral coverage (green, red and near-infrared bands), 3 to 4 times during the cropping season for each crop. Yield maps: Yield maps will be obtained for all fields using combines equipped with calibrated yield monitors and GPS receivers. Yield data will be collected at 1-second intervals, filtered and analyzed for quality control. Grain composition: Grain samples will be removed from fields before or during harvest. Locations within the field from which samples were removed will be GPS referenced and can be layered onto the maps of soil and landscape characteristics. Grain will be analyzed for protein percentage, oil percentage, and fatty acid profiles using both wet chemistry and NIR procedures. Image and statistical analyses: Spectral Visions-Midwest will provide aerial images from their airborne hyperspectral radiometer. Dr. Jim Hipple, Department of Geography, will assist in image processing and analyses. The data are best handled as a multivariate problem and principal component analysis will be the main method for analysis. Dr. Bullock, University of Illinois, will help with data analyses as part of the larger effort. Measures of variables will be taken from each experimental unit. These variables will be checked for multivariate normality and homogeneity of covariance matrices and grouped in chemical, physical, and biological categories. Multivariate statistical analysis will be conducted in two steps as done by Wander and Bollero (1999).

NON-TECHNICAL SUMMARY: To capture additional profit from soybean, farmers should consider adding value through the production of varieties with user-specified composition. This project will help producers measure spatial variability for value-added traits and how to exloit this variation for a competitive advantage.

PROGRESS: 1994/07 TO 2000/12
A split-root experiment was conducted to determine the effect of soybean cyst nematode (SCN) on macronutrient uptake by soybean. Of particular interest was the effect on K uptake because K deficiency symptoms are often associated with SCN infection. We found that SCN infection did not affect K concentration in leaf-blades but leaf-petiole and stem K content was increased by SCN. Roots infected with SCN had lower K content when grown in a nutrient solution with moderate K availability. Increasing K availability ameliorated the SCN effect. Although producers should apply appropriate amounts of K fertilizer to soybeans, increased K fertilizer application will probably not reduce yield impact from SCN. We found that SCN reduces soybean yield by inhibiting branching. Because boron has been shown to stimulate branching of soybean plants, an experiment was conducted to determine if B or Mg could be used to ameliorate yield reduction by SCN. We found no evidence that foliar application of either nutrient would increase soybean yield of SCN infected soybean plants. We studied the effect of SCN on the growth and development of SCN-susceptible and SCN-resistant soybean varieties. SCN reduced soybean yield by reducing pod number, but the effect of SCN on soybean plants related to weather and other in-season effects. We studied the effects of SCN infection on several isoflavones in soybean seeds. Even with very heavy infection, we found no increase or decrease in the seed concentration of free and conjugated isoflavones.

IMPACT: 1994/07 TO 2000/12
Soybean cyst nematode (SCN) remains the most destructive soybean disease organism in the USA. Our research increases our understanding of how SCN and interacts with soybean to decrease yield. This information will help crop advisers formulate SCN management strategies.

PUBLICATIONS: 1994/07 TO 2000/12
1. Smith, G.J., Wiebold, W.J, Niblack, T.L., Scharf, P.C. and D.G. Blevins. 2000. Macronutrient concentrations of soybean infected with soybean cyst nematodes. Plant and Soil. Accepted for publication.
2. Smith, G.J., Wiebold, W.J, Niblack, T.L., Scharf, P.C. and D.G. Blevins. 2000. Yield components of soybean plants infected with soybean cyst nematode and sprayed with foliar applications of boron and magnesium. J Plant Nutri. 23:827-834.
3. Tremain, J.A. 2000. Soybean cyst nematode effects on soybean growth, development, and yield. M. S. Thesis.
4. Smith. G.J. 1996. Nutrition of soybean as influenced by SCN and K. M. S. Thesis.

PROJECT CONTACT:

Name: Wiebold, W. J.
Phone: 573-882-0621
Fax: 573-884-4317
Email: wieboldw@missouri.edu

Item No. 10 of 19

ACCESSION NO: 0169497 SUBFILE: CRIS
PROJ NO: MO-PSSL0536 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 SEP 1995 TERM: 31 AUG 2001 FY: 2001

INVESTIGATOR: Stevens, W. E.

PERFORMING INSTITUTION:
PLANT SCIENCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

NUTRIENT MANAGEMENT FOR CROPS IN SOUTHEAST MISSOURI

OBJECTIVES: Compare cotton growth, yield and profitability between precision and conventional nutrient management systems; determine N response for rice varieties in drill and water-seeded systems; and determine how soybean yield and quality are affected by foliar and fertigation N applications on narrow and wide row planted soybeans.

APPROACH: Experiments will be conducted to investigate variable rate fertilizer applications for cotton, fertilizer nitrogen management for water seeded rice, and fertigation for soybeans with sprinkler irrigation systems. Soil samples will be collected from 8-ha blocks in cotton fields with variable fertility using composite and grid-point sampling methods. Fertilizer and lime will be applied in strips using uniform and variable rate applications based on soil test results. Profitability of each nutrient management system will be calculated. Two rice varieties will be drill and water-seeded with varying N rates. Soil and plant N levels will be monitored. Soybeans will receive mid and late season nitrogen applications applied foliar and by fertigation. Soybean yield, seed protein and leaf N concentration will be measured.

PROGRESS: 1995/09 TO 2001/08
The soil and water resources of Southeast Missouri provide unique challenges and opportunities for farmers in the region. This project investigated variable rate fertilizer and lime applications on cotton, fertilizer nitrogen management for water seeded rice, and fertigation for soybeans with sprinkler irrigation systems. Field tests showed that variable rate fertilizer technology reduced the total amount of nitrogen and lime recommended for cotton fields. When a 90-m grid soil sampling system was used for variable lime application, the gross returns minus liming costs averaged $1,018 per ha for variable rate as compared to $926 per ha for uniform application. This was based on four site-years. For variable rate nitrogen, we found that dividing fields into management zones based on yield potential was useful. In variable rate applications, less nitrogen was applied in the sandy zones of a cotton field. In these areas, water stress was more of limiting factor for cotton yields than nitrogen. Over the course of the study, nitrogen prices fluctuated from $0.07 to $0.14 per kg N due to changes in petroleum prices. When nitrogen was cheap, the application costs for variable rate nitrogen exceeded the savings in fertilizer. In the Northern Mississippi Delta region, no-till water-seeded rice farmers apply all of the nitrogen fertilizer on fields after flooding. The objective of a field experiment was to determine the optimum timing for making the first N application in this system. Two-year results showed that significantly more early tillers and rice yield were obtained when early N applications were delayed 30 to 35 days after seeding (DAS). This was equivalent to 350 to 430 growing degree days base temperature 10 degrees C (GDD10) after seeding. Averaged across years and N rates, rice with the first N applied 30 DAS yielded 7817 kg per ha. Rice receiving the first N applied 15 DAS produced 5819 kg per ha. Regression analysis showed that the optimum timing for the first N application was 35 DAS at a rate of 101 kg N per ha. This was followed by two mid-season N applications. A study was conducted to determine whether applying mid-season nitrogen by fertigation to soybeans would increase yields. The tests contained plots with soybeans planted in 96-cm rows and 17-cm drills. Nitrogen treatments were an untreated check with no nitrogen, a 22 kg per ha nitrogen treatment at R4 (full pod), two 22 kg ha nitrogen applications at R4 + R5 (beginning seed), and three 22 kg ha nitrogen at R4 + R5 + R7 (beginning maturity). We found a greater yield increase from nitrogen fertigation in drilled than row soybeans. In 1995, 22 kg N per ha increased soybeans yields 672 kg per ha in drilled soybeans. In soybeans planted on 90-cm rows, 66 kg N per ha increased soybeans yields only 201 kg per ha. The same pattern occurred in 1996, but was less dramatic. In 1996, soybean yields without fertigation were 2284 kg per ha with rows and 2754 kg per ha with drill. Soybeans with three fertigations (66 kg N per ha) yielded 2620 kg per ha with rows and 3426 in the drill.

IMPACT: 1995/09 TO 2001/08
Cotton studies showed that variable rate nitrogen applications are the most profitable when fields are divided into management zones. Zones with low yield potential should receive less nitrogen fertilizer than high yield potential zones.

PUBLICATIONS: 1995/09 TO 2001/08
1. Stevens, G., S. Hefner, and T. Gladbach. 2001. Effect of nitrogen timing and rates on tillering and yield of no-till water-seeded rice. Communications in Soil Science and Plant Analysis. 32: 421-428.
2. Stevens, G., D. Dunn, and B. Phipps. 2001. How to diagnose soil acidity and alkalinity problems in crops: a comparison of soil pH test kits. [Online] Journal of Extension. 39:4, Available at http:/www.joe.org/joe/2001august/tt3.html (Verified 11 Jan. 2002). Dunn, D., B. Phipps, G. Stevens, and A. Phillips. 2001. Effect of CaSO4 (gypsum) on cotton lint yields, soil fertility, and physical properties of heavy clay soils in Missouri. Proceedings of Missouri Academy of Science. 35:1-5.
3. Davis, G., Dunn, D. and G. Stevens. 2001. Site-specific nitrogen management for cotton. Proc. Soil Mgmt. and Plt. Nut. Conf., Proc. Beltwide Conf., Anaheim, CA Jan 9-13. p. 569.
4. Dunn, D., G. Stevens, and M. Milam. 2001. Portable pH meter for in-field soil testing. Proc. Soil Mgmt. and Plt. Nut. Conf., Proc. Beltwide Conf., Anaheim, CA Jan 9-13. p. 611.
5. Stevens, W.E., and D. Dunn. 2001. Calculating maximum economic returns on nitrogen fertilization on corn, cotton, and rice. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25 no. c00-dunn133516-d.
6. Birmingham, K., W.E. Stevens, D. Dunn, and P. Motavalli. 2001. Effect of mechanical soil compaction on soybean growth and grain yields. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25 , no. s06-dunn115409-p.
7. Sheckell, P., W.E. Stevens, D. Dunn, and J. Lory. 2001. Using chicken litter to increase productivity of freshly graded ground. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25, no. s04-dunn091617-p.
8. Wilson, H. and W.E. Stevens. 2001. Timing of flood termination for water-seeded rice. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25 no. s06-dunn1425332-p.
9. Dunn, D., and W.E. Stevens. 2001. Rice yields response to mid-season potassium fertilization. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25, no. s04-dunn141123-0.
10. Moylan, C., W.E. Stevens, D. Dunn, J. Williams, and N. Kitchen. 2001. Using a chlorophyll meter to predict yield response to in-season nitrogen fertilization of corn. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25, no. s04-dunn084610-d. Stevens, G., A. Kendig, A. Wrather, and M. Boyd. Missouri Degree Day-50 Model. University of Missouri Commercial Agriculture Program and Extension/Outreach. [Online]. Available at http://agebb.missouri.edu/rice/ricemodel.htm.
11. Williams, J., N. Kitchen, P. Scharf, and W. Stevens. 2001. Detecting spatially variable corn nitrogen needs using aerial photography. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25, no. s04-williams151054-p.
12. Motavalli, P., S. Anderson, R. Kremer, W. Stevens, and D. Dunn. 2001. Effects of surface and subsoil compaction on nitrogen availability and carbon transformations. Amer. Soc. of Agronomy Meetings Abstracts, Charlotte, NC Oct. 21-25, no. s04-motavalli202815-o.


Item No. 11 of 19

ACCESSION NO: 0155597 SUBFILE: CRIS
PROJ NO: MO-SSSL0051 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 JUL 1994 TERM: 30 JUN 2000 FY: 2000

INVESTIGATOR: Ikerd, J. E.

PERFORMING INSTITUTION:
SOCIAL SCIENCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

ON-FARM EVALUATION OF SUSTAINABLE WHOLE-FARM SYSTEMS

OBJECTIVES: To assess the economic and ecologic sustainability of various alternatives to conventional methods of nutrient management, pest management, and soil conservation within whole-farm systems.

APPROACH: Research will be carried out on commercially operated farms. Specific on-farm research projects related to the sustainability of various farming practices will be designed to statistical validity as component research but will be evaluated within the context of operational whole-farm systems.

PROGRESS: 1994/07 TO 2000/06
The last 6 months of this project were spent in close-out activities. 115 demonstration projects were funded during the life of the project and the State of Missouri plans to fund 30/year in the future.

IMPACT: 1994/07 TO 2000/06
The program received high praise from constituent groups during hearings held by a Missouri legislative interm committee of Small Farms and Value Added Agriculture in late 1998. This program is currently considered one of the most successful programs in sustainable agriculture for small farms in the state.

PUBLICATIONS: 1994/07 TO 2000/06
No publications reported this period


Item No. 12 of 19

ACCESSION NO: 0156168 SUBFILE: CRIS
PROJ NO: MO-SSSL0188 AGENCY: CSREES MO.
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 SEP 1994 TERM: 31 DEC 2000 FY: 2001

INVESTIGATOR: Prato, A. A.

PERFORMING INSTITUTION:
SOCIAL SCIENCES
UNIVERSITY OF MISSOURI
COLUMBIA, MISSOURI 65211

SPATIAL DECISION SUPPORT SYSTEM FOR TOTAL WATERSHED MANAGEMENT

OBJECTIVES: 1. Design a user-friendly, interactive MODS system that identifies the relative contribution of sub-watershed areas to agricultural nonpoint source pollution and evaluates the effects of alternative land use/management activities and practices (LUMAPs) on farm income, soil erosion, surface water quality and fishery characteristics of aquatic ecosystems at the watershed scale. 2. Demonstrate the utility of the MODS system in identifying and evaluating: a) LUMAPs for controlling soil erosion, surface water pollution, and ecological degradation and b) complementarities and tradeoffs among socioeconomic and environmental objectives in a particular agricultural watershed. 3. Employ the MODS system to evaluate alternative agricultural/environmental policies for reducing agricultural nonpoint source pollution and enhancing the sustainability of agricultural production at the watershed scale.

APPROACH: The MODS system integrates a graphical user interface (GUI), a geographic information system (GIS) and an economic-environmental modeling system. The GUI provides access to the GIS and modeling system and allows the user to select LUMAPs, parameters and evaluation criteria needed to run the MODS system. ARC/INFO GIS is used to manipulate spatial and non-spatial data needed to evaluate alternative watershed management plans. The physical process model simulates soil erosion, sedimentation and runoff and water quality for alternative LUMAPs. The ecological model simulates within-stream biological characteristics related to fish and invertebrate communities and their response to changes in water quantity and quality. The economic model evaluates the effects of a particular spatial configuration of LUMAPs on annualized net returns at the field, farm and watershed scales. Two Missouri watersheds will be evaluated using the MODS system.

PROGRESS: 1994/09 TO 2000/12
Progress Narrative Work continued in several areas: a) evaluating the economic value of riparian buffers in reducing agricultural nonpoint source pollution in Goodwater Creek watershed, Missouri, b) development of a upper partial moment (UPM)-based model for evaluating the economic impacts of enforcing safety-first environmental constraints for reducing nonpoint source pollution in watersheds, c) development of a multiple attribute decision-making model (MADM) that explains how a private or public decision-maker selects a site/landscape management plan for a property based on biophysical and economic attributes of the plan, the decision-maker's preferences for attributes, and constraints on plan selection, d) design of a two-stage hierarchical framework for identifying the management action that is most likely to result in a sustainable ecosystem, and e) a multiple attribute evaluation of alternatives for managing the Missouri River. Empirical results show that the economic value of riparian buffers depends on the water quality objective being pursued and riparian buffers have substantial economic value in maintaining water quality in Goodwater Creek watershed. The UPM solution gives very conservation results compared to a model that assumes environmental objectives for reducing nonpoint source pollution are normally distributed (ND). Unlike the ND solution, the UPM solution strictly achieves the probability of compliance with environmental objectives. The MADM framework is appropriate for modeling and explaining the selection of management plans at the property and watershed scales and can be used by a watershed alliance to evaluate the weak and strong sustainability of alternative management plans at the watershed scale. Bayes theorem provides a useful way to account for uncertainty about whether a particular policy achieves sustainable resource conditions. Bayes rule is well suited for solving the first stage of the two-stage hierarchical framework for identifying management actions that are most likely to result in a sustainable ecosystem state. The second stage of the framework is solved by using MADM to rank the ecologically sustainable ecosystem states identified in the first stage based on their non-ecological attributes. The Mississippi River alternative, which provides a minimum target flow for the Missouri River at its confluence with the Mississippi River, is preferred to the current water control plan and six other alternatives for the Missouri River System under four attribute-weighting schemes. For seven of the eight cases evaluated (two utility functions times four attribute weighting schemes), the average utility score was higher for the two water conservation alternatives than for the two fish and wildlife alternatives. The average rank taken over the four attribute weighting schemes was higher for the water conservation alternatives than the fish/wildlife alternatives with both utility functions. As the percent weight assigned to fish/wildlife attributes increases, the water conservation and fish/wildlife alternatives become more preferred to the current water control plan.

IMPACT: 1994/09 TO 2000/12
Impact Riparian buffers placed between agricultural fields and watercourses appear to have substantial economic value in improving water quality. Multiple attribute evaluation is a suitable framework for: a) selecting resource management plans for individual properties and watersheds, b) identifying management actions that are most likely to result in a sustainable ecosystem, and c) evaluating and ranking water management alternatives for major rivers.

PUBLICATIONS: 1994/09 TO 2000/12
1. Publications 2000
2. Prato, T. 2000 Multiple Attribute Evaluation of Landscape Management. Journal of Environmental Management 60: 325-337
3. Prato, T. 2000 Multiple Attribute Bayesian Analysis of Adaptive Ecosystem Management. Ecological Modelling 133: 181-193.
4. Qiu, Z. and T. Prato 2000 In press. Physical Determinants of Economic Value of Riparian Buffers in an Agricultural Watershed. Journal of the American Water Resources Association.
5. Qiu, Z. and T. Prato 2000 In press. Economic Value and Its Physical Determinants of Riparian Buffers in an Agricultural Watershed. Journal of Agricultural and Applied Economics.
6. Qiu, Z., T. Prato, and F. McCamley 2000 In press. Evaluating Environmental Risks Using Safety-first Constraints. American Journal of Agricultural Economics.


Item No. 13 of 19

ACCESSION NO: 0164317 SUBFILE: CRIS
PROJ NO: NEB-10-124 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 JAN 1994 TERM: 31 DEC 1998 FY: 1999

INVESTIGATOR: Supalla, R. J.; Allen, J. C.

PERFORMING INSTITUTION:
AGRICULTURAL ECONOMICS
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

ECONOMIC ANALYSIS OF FARM MANAGEMENT & PUBLIC POLICY ALTERNATIVES FOR IMPROVING GROUNDWATER QUALITY

OBJECTIVES: Evaluate the farm level consequences of alternative technologies and management practices for reducing groundwater pollution from irrigated agriculture. Analyze the adoption behavior of irrigated products with respect to the use of best mangement practices (BMP's) for improving water quality. Evaluate public policy alternatives for improving groundwater quality.

APPROACH: A systems approach is used to assess the economic and environmental tradeoffs associated with alternative management strategies for reducing nitrate contamination of groundwater. Farm level management alternatives will be evaluated to determine best management practices (BMP's). The types of alternatives to be considered include: crop rotations; amount, timing and method of nitrogen application; amount, timing and method of water applications; and crop monitoring technologies. Public policies for encouraging the adoption of best management practices will also be evaluated, including educational programs, incentives and direct regulations.

NON-TECHNICAL SUMMARY: Nitrate pollution of groundwater is an important environmental problem in Nebraska. This project is focused on finding least cost methods of reducing nitrate pollution of groundwater from irrigated agriculture.

PROGRESS: 1994/01 TO 1998/12
This project addressed management options for reducing nitrate pollution of groundwater, using the Central Platte valley of Nebraska as a case study area. The first major finding was that not all producers were maximizing profits and over 80 percent of producers in the region expressed a willingness to voluntarily incorporate environmental considerations in their production decisions even if it significantly reduced profits. Also, several production practices were identified which if adopted by producers would be win-win, i.e., they would increase profits and improve environmental quality. The presence of a strong environmental ethic among producers and the existence of win-win opportunities was unexpected and suggests that it may be possible to improve environmental quality through education programs without the use of conventional command and control or incentive strategies. Another major finding was that the BMP's for reducing nitrate pollution of groundwater in irrigated regions depended substantially on the current quality of the water. When irrigation water contained less than 15 mg/l of nitrate nitrogen, sprinkler irrigation with minimal water applied was the preferred management option, both economically and environmentally. With high nitrate water, however, the best economic option was well managed gravity irrigation, and the best environmental option was sprinkler irrigation applying more water than what was needed to meet evapotranspiration requirements. Precision farming, or Variable Rate Application Technology (VRAT), was evaluated as a management tool for implementing those BMP's which call for more precise management of the nitrogen and/or water input. Simulation results for several hypothetical fields that consisted of different proportions of three soils (Hord, Valentine and Platte Associations) found that VRAT increased corn yield by 9 to 26 percent, decreased water applied by 1 to 6 percent, decreased nitrogen applied by up to 22 percent and decreased nitrogen leached by up to 44 percent. Economic results suggest that producers could afford to pay from $9 to $26 per acre per year for VRAT technology and still be as well off financially as they would be using conventional practices. Estimates of the elasticity of demand for nitrogen suggest that own price elasticity has fallen from greater than -1.0 to less than -0.2, as producers have become more environmentally concerned and education programs to improve management have intensified. At an elasticity level of -0.2, it wold cost over $1.00 per pound to reduce leaching at the current use level margin. In contrast, the adoption of Best Management Practices (BMP's) was found to reduce nitrate leached at a cost of from less than zero (win-win situation ) to about $0.50 per pound. A contingent valuation and an averting cost study of willingness to pay for improved water quality in Nebraska was also conducted. Contingent valuation results indicated that consumers were willing to pay an average of $9.50 per household per month to reduce nitrate pollution to levels below the public health standard.

IMPACT: 1994/01 TO 1998/12
The primary payoffs from this research are improved water quality and increased economic returns to agriculture. These gains result from the adoption of the improved nitrogen and water management practices. Available evidence for nitrogen management indicates that irrigated producers on the average apply at least 50 pounds per acre of excess N. If only 10 percent of irrigators are induced by this research (and related programs) to reduce excess applied N by only 25 pounds per acre, it would mean an annual reduction in pollution of 10,000 tons of nitrate nitrogen and an increase in net economic returns of $3,000,000 per year.

PUBLICATIONS: 1994/01 TO 1998/12
1. Supalla, R. J., R. A. Selley, S. Bredeweg and D. G. Watts. 1995. "Factors Affecting Adoption of Practices to Improve Water Quality." Journal of Soil and Water Conservation, Jan./Feb.
2. Supalla, R. J., W. M. Miller and B. Julianno. 1996. "Linkages Between Technology Adoption Behavior in Agriculture and Environmental Policy." The Sixth International Symposium on Social and Resource Management, Pennsylvania State University, University Park, PA.
3. Supalla, R. J., S. Ahmad and R. A. Selley. 1996. "Policy Implications of Win-Win Opportunities for Improving Groundwater Quality in Irrigated Areas." Abstract, AJAE, Vo. 78, No. 5.
4. Khan, M. A. and R. J. Supalla. 1997. "Elasticity of Demand for Nitrogen: Implications for Environmental Policy." Selected Paper, Southern Agricultural Economics Association Annual Meeting, Birmingham, Alabama, February 1-5.
5. Ahmad, S. and R. J. Supalla. 1997. "Potential Economic and Environmental Returns to Variable Rate Application of Nitrogen." Selected Paper, Southern Agricultural Economics Association Annual Meeting, Birmingham, Alabama, February 1-5.
6. Ahmad, S., R. A. Selley and R. J. Supalla. 1997. "Policy Alternatives for Improving Groundwater Quality in Irrigated Areas." Selected Paper, Western Agricultural Economics Association Annual Meeting, Reno, Nevada, July 13-16.
7. Ahmad, S., R. J. Supalla and W. M. Miller. 1997. "Precision Farming for Profits and Environmental Quality: Problems and Opportunities." Poster Paper, American Agricultural Economics Association Annual Meeting, Toronto, Canada, July 27-30.
8. Juliano, B. D. 1997. "Factors Affecting Nitrogen Management Practices of Corn Producers in Nebraska." Unpublished M.S. Thesis, University of Nebraska-Lincoln.
9. Sukharomana, R. "Willingness to Pay for Water Quality Improvement: Differences Between Contingent Valuation and Averting Expenditure Methods." Unpublished Ph.D. Thesis, University of Nebraska-Lincoln, 1998.
10. Sukharomana, R. and R. J. Supalla. 1998. "Effect of Risk Perception on Willingness to Pay for Improved Water Quality." Abstract, AJAE, Vol. 80, No. 5.
11. Supalla, R. J. and S. Ahmad. 1998. "An Economic Analysis of Precision Farming as a Tool to Improve Profits and Environmental Quality." Abstract, AJAE, Vol. 80, No. 5.

PROJECT CONTACT:

Name: Supalla, R. J.
Phone: 402-472-1792
Fax: 402-472-3460
Email: rsupalla@unlnotes.unl.edu

Item No. 14 of 19

ACCESSION NO: 0133601 SUBFILE: CRIS
PROJ NO: NEB-12-173 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 05 JAN 1993 TERM: 31 DEC 1998 FY: 1999

INVESTIGATOR: Frank, K. D.; Denning, J. L.

PERFORMING INSTITUTION:
AGRONOMY
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

EVALUATING PLANT NUTRIENT NEEDS AND PRODUCT QUALITY

OBJECTIVES: 1. To cooperate with various ARD projects by providing chemical, physical & biological analyses of soil, plant & water samples. 2. Improve correlation & calibrations of soil testing methods currently available with crop response to lime & fertilizer treatment of a range of Nebraska soils. 3. Investigate & adapt new sample preparation procedures & new analytical techniques for water, plant & soil analyses. 4. Develop & update equations from correlation of NIRS analyses with wet chemistry forage & grain quality procedures.

APPROACH: 1. Maintain & operate a laboratory facility to service research projects needingelemental chemical analyses of soil, plant, water & grain & forage quality by NIRS & PSA of soils. 2. Cooperate with other research projects that generate field or greenhouse data for correlating or calibrating soil test methods with crop response or nutrient uptake. Analyze & use data from soil survey samples to refine soil test interpretation on basis of nutrient contribution of subsoil. 3. Develop & maintain NIRS equations for forage quality parameters using data from cooperating ARD & ARS projects for running both research & public samples. NIRS scans from selected research & commercial samples are equated to data from wet chemistry procedures by regression. 4. The accuracy of elemental analyses of forages & grain by NIRS/NIRT will be studied by comparing with EDXRF results.

NON-TECHNICAL SUMMARY: Rapid and accurate analysis of plant and soil nutrients is important for efficient use of nutrient resources in crop production. This project evaluated old and new methods of soil and plant analysis for accuracy and environmentally friendly methods.

PROGRESS: 1993/01 TO 1998/12
The main accomplishments during the life of this project were: 1) developed and/or improved N, P, K. Zn, S and lime recommendations for corn, wheat, sorghum, alfalfa, soybeans and pastures. 2) adapted Near-infrared Spectrometry (NIR) techniques to determine IVDMD, Crude Protein, NDF, ADF, and DM values for legume and grass hays, corn silage and feed grains. 3) Adapt NIR-T methods for predicting protein, oil, moisture, wet mill starch, and total starch for corn. 4) NIR-R and NIR-T to predict oil, protein and moisture for soybeans. 5) Develop the use of X-ray fluorescence to replace chemical digestion methods to determine, P, K, S, Cl, Mg, Mn, Zn, Fe, Cu and other minerals for plant, soil and organic amendments with success in most situations. Work is still underway to improve precision of determining, e.g., P in a mixed matrix (soil and manure mixture typical of open feedlots). 6) Investigations are underway to develop calibration and correlation equations to determine concentration of nutrients in liquid and dry fertilizers. 7) developed methods to replace chemical determination of easily oxidizable Carbon in soil by combustion (carbon/N analyzer). This involved destruction of excess lime in calcareous soils. 8) On-going collaboration with Super Critical Fluid Equipment Manufacture (ISCO) in developing extraction methods for oil and fat from grains (canola, corn, soybeans/meal and hydrocarbons from soil.) Also "energy packages" were developed for silages, haylages, and total mixed rations. Samples of canola, high oil corn and soybeans and sorghum from diverse areas are utilized to improve oil prediction equations by NIR-R and NIR-T. 9) Member of initial NIR forage analysis consortium to improve the precision of forage analysis values by NIR. 10) Collaborated with other land grant laboratories in developing North American proficiency testing program (soil and plant material). 11) Provided guidance to NE Dept of Agriculture to maintain accuracy in the NE soil and plant analysis check program for all laboratories operating in the state. 12) Cooperative study with commercial laboratories to a) develop correlation between ICP Sulfur and Ion Chromatograph determination of sulfate-S for soils; b) develop extraction techniques using Bray and Kurtz 1 to simultaneously determine Nitrate-N and phosphate-P by flow injection analysis (FIA). Continued refinement of methods for NIR-R, NIR-T and SFE will continue under normal laboratory.

PUBLICATIONS: 1993/01 TO 1998/12
No publications reported this period

PROJECT CONTACT:

Name: Cassman, K. G.
Phone: 402-472-1555
Fax: 402-472-7904
Email: kcassman1@unl.edu

Item No. 15 of 19

ACCESSION NO: 0155682 SUBFILE: CRIS
PROJ NO: NEB-12-209 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: REVISED
START: 01 OCT 2001 TERM: 31 AUG 2006 FY: 2002

INVESTIGATOR: Spalding, R. F.

PERFORMING INSTITUTION:
AGRONOMY
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

PROCEDURES FOR ASSESSING IMPACTS OF NONPOINT AGRICHEMICALS ON GROUNDWATER

OBJECTIVES: The impacts of farm scale conversions to improved herbicide management alternatives on shallow groung water quality wil be investigated at the sprinkler-irrigated MSEA site and at furrow irrigated fields in Nebraska. Changes in herbicide loading to shallow ground water will be evaluated using systems of multilevel samplers and ground water dating. Impacts of runoff and infiltration through grassed buffer strips will be investigated at the farm scale paired watersheds on the water quality in Clear Creek and on shallow ground water beneath the biffered areas. The paired watersheds will allow for comparability between herbicide loss in runoff transported through the buffered and non-buffered row cropped fields. Seven sutomatic ISCO samplers are installed at strategic points in the stream to allow for runoff monitoring of sediment, nitrate, ammonia and herbicides and their transformation products. Chemical infiltration beneath the strips will be detected with lysimeters and multilevel samplers.

APPROACH: Demonstrate performance of amended biodenitrification at a municipal well field in Wahoo, Nebraska. Multilevel samplers will be monitored to determine the degree of treatment within the denitrification zone.

NON-TECHNICAL SUMMARY: Irrigation management impacts ground and surface water quality. Ground water nitrate can be treated by in situ denitrification. This project examines the impact of management alternatives on ground water and surface water quality. This project devlops in situ aquifer methods to remediate ground water nitrate concentrations.

PROGRESS: 2001/10 TO 2002/09
Two manuscripts are now in press that may change researchers' approaches to understanding non point pesticide contamination in shallow aquifers. The data indicate that past reliance on vulnerability models using soil permeability (type), depth to ground water and irrigation to delineate areas vulnerable to pesticide contamination is oversimplified. Results from the four year monitoring study at the NE-MSEA indicate peak pesticide loading to the shallow ground water occurs prior to irrigation after intense storms in specific locations on and off cultivated fields. Recharge areas occurred in field ditches and low spots and especially in road ditches which normally surround each section. N-15 analysis of nitrate in groundwater beneath cropland fertilized with animal and meat processing lagoon wastes indicate that both heterotrophic and dissimilatory nitrate reduction to ammonia occurred. Results of the in situ biodenitrification project at Wahoo, NE municipal well field indicate that the pilot treatment was successful. Two manuscripts describing the fate and transport of ethanol and MTBE in ground water are in the final stages of polishing before submission.

IMPACT: 2001/10 TO 2002/09
A re-evaluation of the dominant mechanisms for pesticide contamination of shallow ground water is needed. Natural attenuation of nitrate occurred in areas where excessive waste applications occurred and appears responsible for keeping average ground water nitrate concentrations close to compliance levels. The successful in situ treatment of nitrate contaminated ground water at the Wahoo well field indicates that the method will provide an economic alternative for municipalities. The only available alternatives are very expensive above ground treatments.

PUBLICATIONS: 2001/10 TO 2002/09
1. Spalding,R.F., Snow, D.D., and Exner, M.E. 2002. Acetamides and their transformation products in ground water beneath Nebrsaksa's Management Systems Evaluation Area. p. 125-128. In T. Albanis (ed) Proceedings of the 2nd Europeon Conference on pesticide and related organic micropolutatants in the environment. University of Ioannina, Corfu, Greece, Sept. 26-29.
2. Exner,M.E., Harrell D., Larsen, P.L.. Romary C., and Spalding, R.F. 2002. A quality assessed database for pesticides in ground water. p.87-92.In T. Albanis (ed) Proceedings of the 2nd Europeon Conference on pesticide and related organic micropolutatants in the environment. University of Ioannina, Corfu, Greece, Sept. 26-29.
3. Snow, D.D., Cassada D.A., Monson S.J., Zhu J., and Spalding R.F. 2002. Trace analysis of tetracycline and macrolide antibiotics using solid phase extraction and liquid chromatography tandem mass spectrometry. In: Abstracts of Papers, 223rd ACS National Meeting, April 7-11. Orlando, FL.

PROJECT CONTACT:

Name: Spalding, R. F.
Phone: 402-472-8214
Fax: 402-472-9599
Email: rspalding@unl.edu

Item No. 16 of 19

ACCESSION NO: 0159768 SUBFILE: CRIS
PROJ NO: NEB-12-228 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 NOV 1992 TERM: 30 APR 1998 FY: 1999

INVESTIGATOR: Sander, D. H.

PERFORMING INSTITUTION:
AGRONOMY
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

INCREASING FERTILIZER EFFICIENCY FOR GRAIN CROPS

OBJECTIVES: 1. Increase efficiency of N and P fertilizer through improved methods of applications. 2. Improve fertilizer recommendations based on soil tests by improved soil sampling & by quantifying corn N uptake in relative to time of N application & degree of N deficiency. 3. Determine reserve capacity of Nebraska soils to supply P before yield response to fertilizer P can be effected.

APPROACH: Fertilizer efficiency will be improved by studying various methods of application in field experiments. Approaches for P will involve manipulating soil-fertilizer contact and root-fertilizer contact to maximize fertilizer uptake. Nitrogen fertilizer efficiency will be improved by studying the effect of delayed soil sampling time on the accuracy of soil test prediction of N need and by evaluating the quantitative effect of time of N application on yield increases under various degrees of N deficiency. Greenhouse and laboratory studies will be used to evaluate the long-term ability of Nebraska soils to supply P.

PROGRESS: 1992/11 TO 1998/04
Two long-term experiments were established in 1996 and 1997 to determine the fertilizer N equivalency and N mineralization of various rates of biosolids obtained from the City of Lincoln's waste treatment plant. One experiment is on continuous irrigated corn and the other on continuous dryland grain sorghum. Rates of biosolids are being applied each year to new plat areas and residual N effects determined from previous applications. N mineralization is being determined from in situ mineralization cans located in the experimental area. Soil moisture and temperature are being monitored. Data generally indicates that for irrigated corn the rate of biosolids that produced maximum yield the first year would produce 83 and 66% of maximum one and two years after applied. The biosolids rate that produced maximum yield the first year for dry land sorghum resulted in 89 and 77% of maximum one and two years after applied. At these rates the biosolids would be half as affective 1.4 years after application for irrigated corn and 1.9 years after application for dry land sorghum.

PUBLICATIONS: 1992/11 TO 1998/04
1. Sander, D.H., and B Eghball. 1999. Planting date and phosphorus fertilizer placement effects on winter wheat. Agron. J. 91:707-712.
2. Binder, D.L., and D.H. Sander. 1998. Border row effect on corn grain response to sidedressed nitrogen fertilizer. Commun. Soil Sci. Plant Anal. 29 (9&10):1349-1354.


Item No. 17 of 19

ACCESSION NO: 0168886 SUBFILE: CRIS
PROJ NO: NEB-12-244 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 05 JUL 1995 TERM: 30 JUN 2000 FY: 2001

INVESTIGATOR: Powers, W. L.

PERFORMING INSTITUTION:
AGRONOMY
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

SOIL PHYSICAL RELATIONSHIPS FOR BEST MANAGEMENT PRACTICES TOPROTECT WATER QUALITY

OBJECTIVES: A. Establish criteria for selecting best management practices (BMPs) based on soil physical relationships which affect surface and ground water quality. B. Determine the effect of present BMPs on soil physical relationships which affect surface and ground water quality.

APPROACH: To achieve objective A, the LEACHM (Leaching Estimation and Chemistry Model) will be used to develop and evaluate remediation practices (based primarily on soil physical relationships) for soils contaminated with munitions (TNT, RDX, etc). This same model along with others will be used to select irrigation regimes for turf grass. A simple technique using a sieving technique will be used to quantify the shape of soil aggregates which can effect fate and transport of agrichemicals. To achieve objective B, the effect of long-term best management practices (BMPs) for applying animal and municipal by-products to soil will be examined in light of their influence on the K factor of the Revised Universal Soil Loss equation (RUSLE) and on soil physical properties such as infiltration rate (permeability), pore size distribution, bulk density, and dry aggregate size distribution.

NON-TECHNICAL SUMMARY: NA

PROGRESS: 1995/07 TO 2000/06
The purpose of this project was to establish soil physical relationships for selecting BMPs and to examine the effect of present BMPs on soil physical relationships. This project consisted of the following four field studies: (1) Alternative production system effect on the K-factor of the Revised Universal Soil Loss Equation; (2) Soil quality assessment after weed-control tillage in a no-till wheat-fallow cropping system; (3) Soil condition as influenced by cropping and tillage systems in the Central High Plains; and (4) Spatial characterization of soil physical properties in irrigation furrows. Study (1) indicated that alternative production systems do affect the K-factor of some soil series and can reduce soil erodibility and erosion. Study (2) showed that occasional tillage with the moldboard plow in a reduced or no tillage management system for wheat will help control winter annual grass weeds without destroying the soil physical benefits of conservation tillage. Study (3) showed that the type and frequency of tillage and cropping systems do affect some soil physical properties. Water infiltration rates were affected as conventional-till (CT) systems tended to have slower intake rates than reduced-till (RT) and no-till (NT) systems. Bulk density under CT systems was greater than that under NT systems. Study (4) showed that the saturated hydraulic conductivity, bulk density, and penetrometer resistance differ significantly among each furrow in an eight-row equipment pass. However, this repeating pattern for penetrometer resistance was not significant below the six-inch soil depth.

IMPACT: 1995/07 TO 2000/06
Study (1): Alternative production systems do affect the K-factor of some soil series and should be taken into consideration when developing conservation plans. Study (2): Because occasional plowing (every 5-6 yrs or so) to control annual grasses has no detrimental long-term effect on the physical quality of soils, the adoption of this relatively inexpensive practice for no-till systems could improve the economic return from land in the High Plains of the United States. Study (3): Although the soil physical properties evaluated varied with tillage/cropping system, no one system seems superior in all aspects. Thus High Plains producers can use any of the evaluated systems as best management practices. However, soil physical properties should be monitored on an ongoing basis. Study (4): Field measurements from this study should be useful in furrow-irrigation simulation models to find environmentally favorable and less expensive water management options.

PUBLICATIONS: 1995/07 TO 2000/06
1. Kessavalou, A., J.W. Doran, W.L. Powers, T.A. Kettler, and J.H. Qian. 1996. Bromide and nitrogen-15 tracers of nitrate leaching under irrigated corn in central Nebraska. Journal of Environmental Quality. 25:1008-1014.
2. Woodbury, B.L., S.D. Comfort, and W.L. Powers. 1996. An automated sampling system for large soil column transport studies. Transactions of the American Society of Agricultural Engineers. 39:2163-2166.
3. Aslan, M., J. Skopp, and W.L. Powers. 1998. Modified proportional model for time-dependent sieving. Soil Science. 163:472-481.
4. Powers, W.L., M.L. House, R.D. Tejral, and D.E. Eisenhauer. 1999. A simultaneous data collection system for several soil water release curves. Applied Engineering in Agriculture. 15:477-481.
5. Krishnan, G., G.L. Horst, S. Darnell, and W.L. Powers. 1999. Growth and development of smooth bromegrass and tall fescue in TNT-contaminated soil. Environmental Pollution. 101:1-8.
6. Kettler, T.A., D.J. Lyon, J.W. Doran, W.L. Powers, and W.W. Stroup. 2000. Soil quality assessment after weed-control tillage in a no-till wheat-fallow cropping system. Soil Science Society of America Journal. 63:339-346.
7. House, M.L., W.L. Powers, D.E. Eisenhauer, D.B. Marx, and D. Fekersillassie. 2001. Spatial analysis of machine-wheel traffic effects on soil physical properties. Soil Science Society of America Journal. 64:Sept-Oct.

PROJECT CONTACT:

Name: Powers, W. L.
Phone: 402--472--1529
Fax: 402-472-7904
Email: wpowers@unlnotes.unl.edu

Item No. 18 of 19

ACCESSION NO: 0164320 SUBFILE: CRIS
PROJ NO: NEB-42-020 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 18 MAR 1994 TERM: 30 NOV 1999 FY: 2000

INVESTIGATOR: Kranz, W. L.

PERFORMING INSTITUTION:
NORTHEAST RES & EXTENSION CNTR
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

EFFECTS OF PREPLANT TILLAGE AND NITROGEN APPLICATION METHOD ON NITRATE LEACHING

OBJECTIVES: 1. Ascertain the influence of preplant tillage on total nitrogen leaching loss &loss via preferential flow pathways. 2. Determine the impact of nitrogen application method of leaching loss. 3. Evaluate the interaction between preplant tillage and nitrogen application for soil leaching loss. 4. Examine the distribution & continuity of preferential flow pathways using image analysis.

APPROACH: Large undisturbed soil monoliths (1 cubic meter) were excavated from field plotswith 15 years of tillage history. Soil monliths were obtained from 3 replications of 3 tillage treatments-moldboard plow + harrow, chisel, & ridgetill. Conservative tracers will be used to simulate nitrogen applied with water, surface broadcast, & slot + compaction. A rainfall simulator will apply water at a 25 mm/hr rate during 2 events. Event 1 will simulate 10 year storm for central Iowa and Event 2 will bring the total water applied to near 1.5 pore volumes. Soil water content will be monitored at 15, 20, 35, 65, and 90 cm below the soil surface using time domain reflectometry. Minitensiometers will be placed adjacent to the TDR waveguides. Readings will be recorded at 15 minute intervals throughout the simulation events. Leachate samples will be collected from a 54 cm square area on the bottom of the monolith using fiberglass wick extractors. Wick extractors will be placed in a 6 x 6 grid arrangement. Following simulation runs the soil will be disected at 10 cm intervals for video imate analysis of macropores.

NON-TECHNICAL SUMMARY: Corn producers use some preplant tillage and nitrogen fertilizer application method combinations that may contribute to nitrate leaching losses. The purpose of this project is to determine which combination of preplant tillage and nitrogen fertilizer application method minimizes nitrate leaching losses from cropland. If successful, producers can use practices that limit contamination of groundwater and surface water.

PROGRESS: 1994/03 TO 1999/11
Nitrogen application was simulated by applying conservative tracers to one meter cubic soil blocks removed from plot areas with 15 years of tillage and cropping history. Tracers were applied to simulate surface broadcast, slot with surface compaction, and with water. A fiberglass wick extraction system was used to collect leachate in a 6 x 6 square grid arrangement. Data analysis suggested that low level surface compaction was not sufficient to direct water around a tracer application zone. Water flow may need to be directed away from the application zone by mounding or doming soil over the application zone in addition to compaction over the area. Because the slot applied tracer was concentrated in a narrow band, leaching loss curves indicated greater losses directly below the application zone regardless where the greatest water losses were recorded. This means that water was not directed around the zone of application effectively. For broadcast applications, nitrate-nitrogen loss was determined by water collections at each grid cell for each water application. After block collection procedures were completed, it was determined that the field area contained soils from three mapping units. These soils have slightly different profiles that may have impacted leaching loss results.

IMPACT: 1994/03 TO 1999/11
For these soil conditions, a) Substantial soil compaction will be necessary to direct infiltrating water around a zone of chemical application. Soil mounding or doming may also be required. b) Variation in small-scale soil properties mask the impact of cultural practices even after 15 years of consistent treatments. c) Additional research is needed to verify the true impact of nitrogen application methods on nitrogen leaching.

PUBLICATIONS: 1994/03 TO 1999/11
No publications reported this period

PROJECT CONTACT:

Name: Kranz, W. L.
Phone: 402-370-4012
Fax: 402-370-4010
Email: wkranz1@unl.edu
URL: http://www.ianr.unl.edu/ianr/nerec/Bill Kranz.htm

Item No. 19 of 19

ACCESSION NO: 0164811 SUBFILE: CRIS
PROJ NO: NEB-48-023 AGENCY: CSREES NEB
PROJ TYPE: HATCH PROJ STATUS: TERMINATED
START: 01 JUN 1994 TERM: 31 MAY 2000 FY: 2000

INVESTIGATOR: Selley, R.

PERFORMING INSTITUTION:
SOUTH CENTRAL RES & EXT CENTER
UNIVERSITY OF NEBRASKA
LINCOLN, NEBRASKA 68583

FORMULATION OF NITROGEN FERTILIZATION RECOMMENDATIONS TO MAXIMIZE ECONOMIC AND ENVIRONMENTAL GOALS

OBJECTIVES: 1. Provide guidance on how to formulate statewide recommendations considering producer and social objectives. 2. Study producer response to recommendations, focusing upon behavioral patterns and producer characteristics, and their influence on producer acceptance. 3. Estimate the cost of collection of site specific information, the cost of recommendation errors due to lack of site specific information, and the cost of adjusting application rates within and between sites. 4. Rank additional information that could potentially lead to refinement in nitrogen fertilization recommendations, e.g. should we be asking for past N levels, whether the land is dryland or irrigated, the type of irrigation.

APPROACH: The objectives of this project will be pursued using data from central Nebraska.It is intended to develop procedures that could be applied to a larger study area such as the State of Nebraska. Producer response to N fertilization recommendations will be studied by identifying patterns of behavior using reports of soil tests and fertilizer application rate submitted to the Central Platte NRD. Obj. 2 will be further pursued through group focus interviews and/or a survey questionnaire. Obj. 3 will be pursued with interviews of producers and dealers to determine sampling and applications costs and to develop budgets to summarize those costs. Obj. 4 will involve using EPIC, a crop simulation model for estimating N leaching and yields.

NON-TECHNICAL SUMMARY: Nitrogen fertilization of crops is profit motivated but has the risk of contamination of ground and surface water. This project seeks to identify procedures for making nitrogen fertilization recommendations that will result in application rates that balance profit and environmental risk.

PROGRESS: 1994/06 TO 2000/05
It was demonstrated that practices designed to protect and improve the groundwater should be evaluated in terms of their net impact upon the ground water. Under irrigation this means determining, for example, nitrate leaching less the nitrate removed from the aquifer through pumping. When recognizing the influence of the nitrate level in the ground water it follows that best management practices may differ depending on the level of nitrate in the ground water. It was also shown that simulating a single point in a gravity irrigated field to evaluate net nitrate leaching can lead to erroneous results. Contrary to expectations, simulation results indicate pumping in excess of crop needs using a gravity irrigation system may be most attractive economically and environmentally when the nitrate levels in the ground water are high. Irrigating for crop needs with a center pivot system is attractive when ground water nitrate levels are low. Also contrary to expectations, a corn-soybean rotation is not always superior environmentally to continuous corn evaluated based on net nitate leaching. It was found in the Central Platte river valley producers typically apply more nitrogen than is recommended when the recommendation is relatively low. However, environmentally concerned, well educated, well informed and younger producers were more likely to apply nitrogen near recommended levels.

IMPACT: 1994/06 TO 2000/05
The major impact of this research has been upon the methods used in evaluating production practices. As these procedures are implemented, best management practices will have to be formulated for the situation, both the environment, the level of understanding on the part of producers and their willingness to bear risk.

PUBLICATIONS: 1994/06 TO 2000/05
1. Zara,P, R.Selley,et.al. 1994. Simulating N Leaching in Furrow Irrigated Corn, Irrig Science. Vol 15, No 4, Dec.
2. Supalla,R, R.Selley,et.al. 1995. Analysis of Factors Affecting the Adoption of Nitrogen Management Practices fot Improving Water Quality. J. of Soil and Water Conservation. Jan-Feb.
3. Selley. R. and P. Wilson. 1997. Risk Research and Public Outreach: A Tale of Two Cultures?. J of Agricultural and Resource Economics, 22(2):222-232.
4. J. Cahoon, R.Selley, et. al. 1999. Corn yield Response to Tillage with Furrow Irrigation. J of Production Ag, Vol 12, No2, Apr-Jun.

PROJECT CONTACT:

Name: Selley, R. A.
Phone: 402-762-3535
Fax: 402-762-4422
Email: RSelley1@unl.edu