Projects

Object Modeling and Scaling of Landscape Processes and Conservation Effects in Agricultural Systems Appropriated (D)   Accession Number: 411543

Enhanced System Models and Decision Support Tools to Optimize Water Limited Agriculture Appropriated (D)   Accession Number: 414564

The Object Modeling System (Oms): An Advanced Computer Framework for Natural Resources Technology Models and Tools Reimbursable (R)   Accession Number: 409370

Develop Knowledge Base and Quantitative Tools for Optimal Crops and Mgmt Practices for Variable Ltd Water Conditions in the Great Plains Specific Cooperative Agreement (S)   Accession Number: 413422

Application of System Models to Evaluate and Extend Cropping Systems Studies at Different Great Plains/northwest Locations Specific Cooperative Agreement (S)   Accession Number: 412167

Publications

A Step by Step Procedure for Parameterization, Calibration, Validation, and Application of a System Model in Field Research - (Abstract) - (05-Aug-09)

Use of a Cropping System Model for Soil-Specific Optimization of Limited Water - (Proceedings/Symposium)

Ahuja, L.R., Anapalli, S.S., Ma, L., Nielsen, D.C., Trout, T.J., Andales, A.A., Hansen, N.C. 2009. Use of a Cropping System Model for Soil-Specific Optimization of Limited Water. International Conference on Precision Agriculture Abstracts & Proceedings.

Space-Time Dynamics of Soil Water and Process Interactions in Semi-Arid Terrain, Colorado, USA - (Proceedings/Symposium)

Green, T.R., Erskine, R.H., Murphy, M.R., Ma, L., Ascough II, J.C., Mcmaster, G.S., Dunn, G.H., Ahuja, L.R. 2009. Space-Time Dynamics of Soil Water and Process Interactions in Semi-Arid Terrain, Colorado, USA. International Congress on Modeling and Simulation Proceedings. p. 1851-1857.

Modeling Responses of Dryland Spring Triticale, Proso Millet and Foxtail Millet to Initial Soil Water in the High Plains - (Peer Reviewed Journal)

Anapalli, S.S., Nielsen, D.C., Lyon, D.J., Ma, L., Felter, D.G., Baltensperger, D.D., Hoogenboom, G., Ahuja, L.R. 2009. Modeling Responses of Dryland Spring Triticale, Proso Millet and Foxtail Millet to Initial Soil Water in the High Plains. Field Crops Research 113:48-63.

Quasi-Biennial Corn Yield Cycles - (Peer Reviewed Journal)

Malone, R.W., Meek, D.W., Hatfield, J.L., Mann, M., Jaquis, R.J., Ma, L. 2009. Quasi-Biennial Corn Yield Cycles. Agricultural and Forest Meteorology. 149(6&7):1087-1094.

Effects of Estimating Soil Hydraulic Properties and Root Growth Factor on Soil Water Balance and Crop Production - (Peer Reviewed Journal)

Ma, L., Hoogenboom, G., Saseendran, S.A., Bartling, P.N., Ahuja, L.R., Green, T.R. 2009. Effects of Estimating Soil Hydraulic Properties and Root Growth Factor on Soil Water Balance and Crop Production. Agronomy Journal. 101:572-583.

Soil Nitrogen Balance Under Wastewater Management: Field Measurements and Simulation Results - (Peer Reviewed Journal)

Sophocleous, M., Townsend, M.A., Vocasek, F., Ma, L., Ashok, K.C. 2009. Soil Nitrogen Balance Under Wastewater Management: Field Measurements and Simulation Results. Journal of Environmental Quality. 38:1286-1301.

Evaluating the Crop Water Stress Index and its Correlation with Latent Heat and CO2 Fluxes Over Winter Wheat and Maize in the North China Plain - (Peer Reviewed Journal)

Li, L., Nielsen, D.C., Yu, Q., Ma, L., Ahuja, L.R. 2008. Evaluating the Crop Water Stress Index and its Correlation with Latent Heat and CO2 Fluxes Over Winter Wheat and Maize in the North China Plain. Agricultural Water Management.doi:10.1016/j.agwat.2008.09.015.

Winter Cover Crop Effects on Nitrate Leaching in Subsurface Drainage as Simulated by RZWQM-DSSAT - (Peer Reviewed Journal)

Li, L., Malone, R.W., Ma, L., Kaspar, T.C., Jaynes, D.B., Saseendran, S.A., Thorp, K.R., Yu, Q., Ahuja, L.R. 2008. Winter Cover Crop Effects on Nitrate Leaching in Subsurface Drainage as Simulated by RZWQM-DSSAT. Transactions of the ASABE. 51:1575-1583.

Drainmod-N Ii: Evaluated for An Agricultural System in Iowa and Compared to Rzwqm-Dssat - (Peer Reviewed Journal)

Thorp, K.R., Youssef, M.A., Jaynes, D.B., Malone, R.W., Ma, L. 2009. DRAINMOD-N II: Evaluated for an agricultural system in Iowa and compared to RZWQM-DSSAT. Transactions of the ASABE. 52(5):1557-1573.

Current Water Deficit Stress Simulations in Selected Agricultural System Simulation Models - (Book/Chapter)

Anapalli, S.S., Ahuja, L.R., Ma, L., Timlin, D.J., Stockle, C.O., Boote, K.J., Hoogenboom, G. 2008. Current Water Deficit Stress Simulations in Selected Agricultural System Simulation Models. In: Ahuja, L.R., Reddy, V.R., Saseendran, S.A., Yu, Q., editors. Response of Crops to Limited Water: Understanding and Modeling Water Stress Effects on Plant Growth Processes. Madison, WI, American Society of Agronomy, Crop Science Society of America, Soil Science Society of America. p. 1-38.

Modeling Nitrogen and Water Management Effects in a Wheat-Maize Double-Cropping System - (Peer Reviewed Journal)

Fang, Q., Ma, L., Yu, Q., Malone, R.W., Saseendran, S.A., Ahuja, L.R. 2008. Modeling Nitrogen and Water Management Effects in a Wheat-Maize Double-Cropping System. Journal of Environmental Quality. 37:2232-2242.

Spatial Features, Scaling and Simulation in Semi-Arid Agricultural Terrain - (Abstract)

Green, T.R., Erskine, R.H., Ma, L. 2008. Spatial Features, Scaling and Simulation in Semi-Arid Agricultural Terrain. American Society of Agronomy Meetings. Paper No. 257-9.

Simulated Effects of Nitrogen Management and Soil Microbes on Soil Nitrogen Balance and Crop Production - (Peer Reviewed Journal)

Ma, L., Malone, R.W., Jaynes, D.B., Thorp, K.R., Ahuja, L.R. 2008. Simulated Effects of Nitrogen Management and Soil Microbes on Soil Nitrogen Balance and Crop Production. Soil Science Society of America Journal. 72:1594-1603.

Simulated Corn Stover Removal Effects on Soil Organic Carbon and Nitrogen Dynamics - (Abstract)

Ma, L., Malone, R.W., Ahuja, L.R., Karlen, D.L., Saseendran, S.A. 2009. Simulated Corn Stover Removal Effects on Soil Organic Carbon and Nitrogen Dynamics. American Society of Agronomy Meetings, Houston, TX, October 5, 2009.

Modeling Crop Responses to Initial Soil Water in the High Plains - (Abstract)

Saseendran, S.A., Nielsen, D.C., Lyon, D.J., Ma, L., Ahuja, L.R. 2008. Modeling Crop Responses to Initial Soil Water in the High Plains. Agronomy Abstract. Presented at the International American Society of Agronomy meetings, Crop Science Society of America and Soil Science Society of America (ASA/CSSA/SSSA) annual meetings. oct. 5-9, 2008. Houston, TX.

Use of Crop Simulation Models to Evaluate Limited Irrigation Management Options for Corn in Semi-Arid Environment - (Peer Reviewed Journal)

Anapalli, S.S., Ahuja, L.R., Nielsen, D.C., Trout, T.J., Ma, L. 2008. Use of Crop Simulation Models to Evaluate Limited Irrigation Management Options for Corn in Semi-Arid Environment. Water Resources Research. Water Resources Research, 44,W00E02, doi10.1029/2007WR006181.

N uptake effects on N loss in tile drainage as estimated by RZWQM - (Book/Chapter)

Malone, R.W., Ma, L. 2008. N uptake effects on N loss in tile drainage as estimated by RZWQM. In: Ma, L., Bruulsema, T., Ahuja, L., editors. New Advances in Understanding and Quantification of Plant N Uptake. Boca Raton, FL. CRC Press. p. 259-275.

Ecological Models: Agricultural Models - (Book/Chapter)

Ascough Ii, J.C., Ahuja, L.R., Mcmaster, G.S., Ma, L., Andales, A.A. 2008. Agricultural Models. In: Jorgensen, S.E., Faith, B.D.editors. Ecological Models. Vol. (1) Encyclopedia of Ecology., 5 vols. Oxford, Elsevier. p. 85-95.

Simulated Corn Yield Responses to Limited-Water Irrigation Under Varying Soil and Climate Conditions - (Abstract)

Anapalli, S.S., Ahuja, L.R., Ma, L., Nielsen, D.C., Trout, T.J., Hansen, N., Andales, A.A. 2007. Simulated Corn Yield Responses to Limited-Water Irrigation Under Varying Soil and Climate Conditions. ASA-CSSA-SSSA Annual Meeting Abstracts, New Orleans, LA. November 5,2007, 33-2.

Spatial Variability and Scaling of Infiltration on Undulating Agricultural Terrain - (Abstract)

Green, T.R., Ahuja, L.R., Dunn, G.H., Ascough Ii, J.C., Mcmaster, G.S., Ma, L., Erskine, R.H., Salas, J.D., Palic, D.B., Murphy, M.R. 2007. Spatial Variability and Scaling of Infiltration on Undulating Agricultural Terrain. American Society of Agronomy Meetings New Orleans, November 7,2007 (282-3).

Scaling Parameters of the Lewis-Kostiakov Water Infiltration Equation Across Soil Textural Classes and Extension to Rain Infiltration - (Peer Reviewed Journal)

Ahuja, L.R., Kozak, J.A., Andales, A.A., Ma, L. 2006. Scaling Parameters of the Lewis-Kostiakov Water Infiltration Equation Across Soil Textural Classes and Extension to Rain Infiltration. Transactions of the ASABE. Vol.50(5): 1525-1541.2007.

System Modeling for Soil and Water Research and Management: Current Status and Needs for the 21st Century - (Peer Reviewed Journal)

Ma, L., Ahuja, L.R., Malone, R.W. 2007. System Modeling for Soil and Water Research and Management: Current Status and Needs for the 21st Century. Transactions of the ASABE. 50(5):1705-1713.

Simulated N Management Effects on Corn Yield and Tile-Drainage Nitrate Loss - (Peer Reviewed Journal)

Malone, R.W., Ma, L., Heilman, P., Karlen, D.L., Kanwar, R.S., Hatfield, J.L. 2007. Simulated N Management Effects on Corn Yield and Tile-Drainage Nitrate Loss. Geoderma. 140:272-283.

Empirical Analysis and Prediction of Nitrate Loading and Crop Yield for a Corn-Soybean Rotations - (Peer Reviewed Journal)

Malone, R.W., Ma, L., Karlen, D.L., Meade, T.G., Meek, D.W., Heilman, P., Kanwar, R.S., Hatfield, J.L. 2007. Empirical analysis and prediction of nitrate loading and crop yield for a corn-soybean rotations. Geoderma. 140:223-234.

Evaluating and predicting agricultural management effects under tile-drainage using modified APSIM - (Peer Reviewed Journal)

Malone, R.W., Huth, N., Carberry, P.S., Ma, L., Kaspar, T.C., Karlen, D.L., Meade, T.G., Kanwar, R.S., Heilman, P. 2007. Evaluating and predicting agricultural management effects under tile-drainage using modified APSIM. Geoderma. 140:310-322.

Using the RZWQM to Simulate the Fate of Nitrogen in Field Soil - Crop Environment in the Mediterranean Region - (Peer Reviewed Journal)

Cameira, M.R., Fernando, R.M., Ahuja, L.R., Ma, L. 2007. Using the RZWQM to Simulate the Fate of Nitrogen in Field Soil - Crop Environment in the Mediterranean Region. Agricultural Water Management. 90:121-136. 2007.

Whole System Integration and Modeling Essential to Agricultural Science and Technology for the 21st Century - (Peer Reviewed Journal)

Ahuja, L.R., Andales, A.A., Ma, L., Saseendran, S.A. 2007. Whole System Integration and Modeling Essential to Agricultural Science and Technology for the 21st Century. Crop Management. Vol.19, No 1/2, April 2007.

Modeling Pesticide Fate and Nonideal Transport From A Slow Release, Pesticide Treated Seed - (Peer Reviewed Journal)

Sabbagh, G.J., Fox, G.A., Ma, L., Malone, R.W., Arthur, E.L., Dyer, D.G. 2007. Modeling Pesticide Fate and Nonideal Transport From A Slow Release, Pesticide Treated Seed. Transactions of the ASABE 50(2):523-532, 2007.

Comparision of modeling approaches to quantify residue architecture effects on soil temperature and water - (Peer Reviewed Journal)

Kozak, J.A., Aiken, R.M., Flerchinger, G.N., Nielsen, D.C., Ma, L., and Ahuja, L.R. 2007, Comparison of modeling approaches to quantify residue architecture effects on soil temperature and water. International Journal of Soil and Tillage Research.95:84-96.

Rzwqm Simulation of Long-Term Crop Production, Water and Nitrogen Balances in Northeast Iowa - (Peer Reviewed Journal)

Ma, L., Malone, R.W., Heilman, P., Karlen, D.L., Kanwar, R., Cambardella, C.A., Ahuja, L.R. 2007. RZWQM simulation of long-term crop production, water and nitrogen balances in northeast Iowa. Geoderma 140(3):247-259. doi: 10.1016/j.geoderma.2007.04.009.

Simulating Management Effects on Crop Production, Tile Drainage, and Water Quality Using Rzwqm-Dssat - (Peer Reviewed Journal)

Anapalli, S., Ma, L., Malone, R.W., Heilman, P., Ahuja, L.R., Kanwar, R., Karlen, D.L., Hoogenboom, G. 2007. Simulating management effects on crop production, tile drainage, and water quality using RZWQM-DSSAT. Geoderma 140:3 (2007)297-309. Published on-line 5/23/2007. doi:10.1016/j.geoderma.2007.04.013.

Evaluation of Crop Water Stress Based On Soil Moisture, Evapotranspiration, and Canopy Temperature - (Abstract)

Yu, Q., Xu, S., Ma, L., Ahuja, L.R. 2006. Evaluation of Crop Water Stress Based On Soil Moisture, Evapotranspiration, and Canopy Temperature. ASA-CSSA-SSSA Annual Meeting Abstracts. Indianapolis, IN. November 13, 2006.

Simulations of Limited-Water Irrigation Management Options for Corn in Dryland Agriculture - (Abstract)

Saseendran, A., Ahuja, L.R., Ma, L., Nielsen, D.C., Dunn, G.H. 2006. Simulations of Limited-Water Irrigation Management Options for Corn in Dryland Agriculture. ASA-CSSA-SSSA Annual Meeting Abstracts. Indianapolis, IN. November 13, 2006.

Applications of Agricultural System Models in Assessing and Managing Contamination of the Soil-Water-Atmosphere Continuum in Agriculture - (Proceedings/Symposium)

Ahuja, L.R., Ma, L., Saseendran, A., Malone, R.W. 2006. Applications of agricultural system models in assessing and managing contamination of the soil-water-atmosphere continuum in agriculture. International Symposium for the Agricultural Environment. International Symposium for the Agricultural Environment.

Soil Organic Carbon Pool Changes under Long-Term No-Till and Cropping Intensity Regimes Across An Evapotranspiration Gradient in Eastern Colorado, Usa - (Abstract)

Ma, L., Sherrod, L.A., Peterson, G., Hansen, N., Ahuja, L.R. 2006. Soil organic carbon pool changes under long-term no-till and cropping intensity regimes across an evapotranspiration gradient in Eastern Colorado, USA. International Soil Tillage Research Organization Proceedings. KIel, Germany. 8/28 - 9/3/2006. (Abstract)

Modeling Effects of Till/no-Till and Surface Crop Residues on Soil Water, Temperature and Energy Balance - (Abstract)

Ahuja, L.R., Anapalli, S.S., Ma, L., Kozak, J.A., Aiken, R.M., Flerchinger, G.N. 2006. Modeling effects of till/no-till and surface crop residues on soil water, temperature and energy balance. International Soil Tillage Research Organization. Kiel, Germany, August 28-September 3, 2006.

Sensitivity of Tile Drainage Flow and Crop Yield on Measured and Calibrated Soil Hydraulic Properties - (Peer Reviewed Journal)

Ma, L., Malone, R.W., Heilman, P., Ahuja, L.R., Meade, T.G., Anapalli, S.S., Ascough Ii, J.C., Kanwar, R.S. 2007. Sensitivity of tile drainage flow and crop yield on measured and calibrated soil hydraulic properties. Geoderma 140:3(2007) 284-296. Published on-line 5/16/2007. doi:10.1016/j.geoderma.2007.04.012

Rzwqm Simulated Effects of Crop Rotation, Tillage, and Controlled Drainage on Crop Yield and Nitrate-N Loss in Drain Flow. - (Peer Reviewed Journal)

Ma, L., Malone, R.W., Heilman, P., Jaynes, D.B., Ahuja, L.R., Saseendran, S.A., Kanwar, R.S., Ascough II, J.C. 2007. RZWQM simulated effects of crop rotation, tillage, and controlled drainage on crop yield and nitrate-n loss in drain flow. Geoderma 140(3):260-271. doi:10/1016/j/geoderma.2007.04.010.

Decision Support for Nitrogen Management in Tile-Drained Agriculture 1825 - (Proceedings/Symposium)

Heilman, P., Malone, R.W., Ma, L., Hatfield, J.L., Ahuja, L.R., Ayen, J., Boyle, K., Kanwar, R. 2006. Decision support for nitrogen management in tile-drained agriculture. In: Voinov, A., Jakeman, A.J., Rizzoli, A.E. (eds). Proceedings of the iEMSs Third Biennial Meeting: "Summit on Environmental Modelling and Software". International Environmental Modelling and Software Society, Burlington, USA, July 2006. CD ROM.

Application of Agricultural System Models in Assessing and Managing Contamination of Soil-Water-Atmosphere Continuum in Agriculture - (Abstract)

Ahuja, L.R., Ma, L., Anapalli, S., Malone, R.W. 2006. Application of Agricultural System Models in Assessing and Managing Contamination of Soil-Water-Atmosphere Continuum in Agriculture. International Symposium for the Agricultural Environment. Ghent, Belgium. September 4-6, 2006. (Abstract).

Empirical Modeling of Nitrate Loading and Crop Yield for Corn-Soybean Rotations in Iowa - (Abstract) - (11-May-06)

Evaluating Various Water Stress Calculations in RZWQM and RZ-SHAW for Corn and Soybean Production - (Peer Reviewed Journal)

Kozak, J.A., Ma, L., Ahuja, L.R., Flerchinger, G.N., Nielsen, D.C. 2006. Evaluating Various Water Stress Calculations in RZWQM and RZ-SHAW for Corn and Soybean Production. Agronomy Journal 98:1146-1155.

Decision Support for Nitrogen Management in Tile Drained Agriculture 1811 - (Proceedings/Symposium)

Heilman, P., Malone, R.W., Ma, L., Hatfield, J.L., Ahuja, L.R., Ayen, J., Boyle, K., Kanwar, R. 2006. Decision support for nitrogen management in tile drained agriculture. In: Jakeman, A., Rizzoli, A. (eds). Proceedings of the IEMSs Third Biennial Meeting: "Summit on Environmental Modelling and Software". International Environmental Modelling and Software Society, Burlington, USA, July 2006. CD ROM.

An Improved Agricultural System Model for Space-Time Simulation of Agricultural Landscape Variability - (Abstract)

Ascough II, J.C., Ma, L., Green, T.R., Flerchinger, G.N., Mcmaster, G.S., Ahuja, L.R., Vandenberg, B.C. 2006. An improved agricultural system model for space-time simulation of agricultural landscape variability. World Congress of Soil Science. July 9-15,2006.

Applications of Rzwqm in Agricultural Research for Soil and Water Management - (Abstract)

Ma, L., Ahuja, L.R., Saseendran, S.A. 2006. Applications of rzwqm in agricultural research for soil and water management. World Congress of Soil Science. Philadelphia, PA. 7/09/-7/14/2006.(Abstract).

Key Criteria and Selection of Sensitivity Analysis Methods Applied to Natural Resource Models - (Proceedings/Symposium)

Ascough Ii, J.C., Green, T.R., Ma, L., Ahuja, L.R. 2005. Key criteria and selection of sensitivity analysis methods applied to natural resource models. Modsim 2005 International Congress on Modeling and Simulation, Modeling and Simulation Society of Australia and New Zealand, Melbourne, Australia. December 12-15, 2005. p2463-2469.

Key Criteria and Selection of Sensitivity Analysis Methods Applied to Natural Resource Models - (Proceedings/Symposium)

Ascough Ii, J.C., Green, T.R., Ma, L., Ahuja, L.R. 2005. Key criteria and selection of sensitivity analysis methods applied to natural resource models. International Congress on Modeling and Simulation Proceedings. Salt Lake City, UT, November 6-11,2005.

Crop Canopy and Residue Rainfall Interception Effects on Water and Crop Growth - (Peer Reviewed Journal)

Kozak, J.A., Ahuja, L.R., Green, T.R., Ma, L. 2007. Crop canopy and residue rainfall interception effects on water and crop growth. Hydrological Processes. 21:229-241, March 2007.

Crop Canopy and Residue Rainfall Interception Effects on Water and Crop Growth - (Peer Reviewed Journal) - (01-Nov-05)

Modeling a Wheat-Maize Double Cropping System in China Using Two Plant Growth Modules with Rzwqm - (Peer Reviewed Journal)

Yu, Q., Saseendran, S.A., Ma, L., Flerchinger, G.N., Green, T.R., Ahuja, L.R. 2006. Modeling a wheat-maize double cropping system in china using two plant growth modules with rzwqm. Agricultural Systems. 89(2-3):457-477.2006.

Evaluating Nitrogen and Water Management of a Double Cropping System in China - (Peer Reviewed Journal)

Hu, C., Saseendran, S.A., Green, T.R., Ma, L., Li, X., Ahuja, L.R. 2006. Evaluating nitrogen and water management of a double cropping system in china. Vadose Zone Journal. 5:493-505.2006.

Trans-Disciplianry Soil Physics Research Critical to Synthesis and Modeling of Agricultural Systems - (Peer Reviewed Journal)

Ahuja, L.R., Ma, L., Timlin, D.J. 2006. Trans-disciplianry soil physics research critical to synthesis and modeling of agricultural systems. Soil Science Society of America Journal.70:311-326.2006.

Field Scale Water Quality Management in the Us: State of the Art 2005 1814 - (Abstract)

Heilman, P., Ma, L., Malone, R.W. 2005. Field scale water quality management in the us: state of the art 2005. American Water Resources Association Summer Specialty Conference, Institutions for Sustainable Watershed Management: Reconciling Physical and Management Ecology in the Asia-Pacific, Honolulu, Hawaii, June 29, 2005.

Energy Balance and Water and Heat Transfer Simulated by Shaw and Rz-Shaw - (Abstract)

Yu, Q., Kozak, J.A., Xu, S., Flerchinger, G.N., Ma, L., Ahuja, L.R. 2005. Energy balance and water and heat transfer simulated by shaw and rz-shaw. ASA-CSSA-SSSA Annual 2005 Meeting Abstracts. Salt Lake City, UT. Nov. 6-10, 2005.

Spatial Water Quality Modeling Framework Development Using Arcgis9 - (Proceedings/Symposium)

Ascough II, J.C., Green, T.R., Ahuja, L.R., Ma, L., Vandenberg, B.C. 2005. Spatial water quality modeling framework development using ArcGIS9. Proceedings 05-2082. 2005 ASAE Annual International Meeting, Tampa, FL. July 17-20. http://asae/frymulti.com/techpapers.asp?confid=tfl2005.

A New Soil C/n Module to Simulate Denitrification for Groundwater Remediation - (Abstract)

Ma, L., Hunter, W.J., Ahuja, L.R. 2005. A new soil C/N module to simulate denitrification for groundwater remediation. ASA-CSSA-SSSA Annual Meeting Abstracts. Nov. 6-10, 2005. Salt Lake City, UT.

Modeling Impacts of Crop Rotations, Tillage and N Management on Crop Productivity and Water Quality Using the Rzwqm-Dssat Hybrid Model - (Abstract)

Anapalli, S.S., Ma, L., Malone, R.W., Heilman, P., Ahuja, L.R., Kanwar, R.S., Meade, T.G. 2005. Modeling impacts of crop rotations, tillage and N management on crop productivity and water quality using the RZWQM-DSSAT hybrid model. ASA-CSSA-SSSA Annual Meeting, Salt Lake City, UT. Nov. 6-10, 2005.

Development and Evaluation of the Rzwqm-Cropgro Hybrid Model for Soybean Production - (Peer Reviewed Journal)

Ma, L., Hoogenboom, G., Ahuja, L.R., Nielsen, D.C., Ascough II, J.C. 2005.Development and evaluation of the RZWQM-CROPGRO hybrid model for soybean production. Agronomy Journal. 97:1172-1182.

Effectiveness of Rzwqm for Simulating Alternative Great Plains Cropping Systems - (Peer Reviewed Journal)

Saseendran, S.A., Nielsen, D.C., Ma, L., Ahuja, L.R., Vigil, M.F., Benjamin, J.G., Halvorson, A.D. 2005. Effectiveness of RZWQM for simulating alternative Great Plains cropping systems. Agronomy Journal 97:1183-1193.

Effectiveness of Rzwqm for Simulating Alternative Great Plains Cropping Systems - (Proceedings/Symposium)

Anapalli, S.A., Nielsen, D.C., Ma, L., Ahuja, L.R., Vigil, M.F., Benjamin, J.G., Halvorson, A.D. 2005. Effectiveness of RZWQM for simulating alternative great plains cropping systems. Proceedings from the 35th Biological Systems Simulation Conference. April 19-21, 2005. Phoenix, AZ. P. 37-38.

Nitrate Losses in Subsurface Tile Drainage As Affected by Tillage, Crop Rotations, and Fertilizer Management - (Abstract)

Ma, L., Malone, R.W., Saseendran, S.A., Ahuja, L.R., Heilman, P., Kanwar, R.S. 2006. Nitrate losses in subsurface tile drainage as affected by tillage, crop rotations, and fertilizer management. Biological Systems Simulation Group Proceedings. Fort Collins, CO. April 11-13, 2006.

Development and Evaluation of the Rzwqm-Ceres-Maize Hybrid Model for Maize Production - (Peer Reviewed Journal)

Ma, L., Hoogenboom, G., Ahuja, L.R., Ascough Ii, J.C., Saseendran, S.A. 2006. Evaluation of the rzwqm-ceres-maize hybrid model for maize production. Agricultural Systems. 87(3): 274-295.

Assessment of Groundwater Use by Wheat (Triticum Acestivum L.) in the Luancheng Xian Region and Potential Implications for Water Conservation in the Northwestern North China Plain - (Peer Reviewed Journal)

Chunsheng, H., Delgado, J.A., Xiying, Z., Ma, L. 2005. Assessment of groundwater use by wheat (triticum acestivum l.) in the luancheng xian region and potential implications for water conservation in the northwestern north china plain. Journal of Soil and Water Conservation. 60:80-88.

Scaling and Estimation of Evaporation and Transpiration of Water Across Soil Textures - (Peer Reviewed Journal)

Kozak, J.A., Ahuja, L.R., Ma, L., Green, T.R. 2005. Scaling and estimation of evaporation and transpiration of water across soil textures. Vadose Zone Journal. 4:418-427. 2005.

Modeling Spatial Variability in Agriculture: the Agsimsgis Water Quality Tool - (Abstract)

Ascough Ii, J.C., Green, T.R., Ahuja, L.R., Vandenberg, B.C., Ma, L. 2004. Modeling spatial variability in agriculture: the agsimsgis water quality tool. Meeting Abstract. ESRI Southwest Users Group 2004 conference, Telleride, CO, October 20-22, 2004. www.swuggis.org/swug_2004/abstracts.shtml.

Practical Application of Sensitivity and Uncertainty Analysis Techniques: Lessons Learned with Two Agricultural System Models - (Abstract)

Ascough Ii, J.C., Ma, L. 2004. Practical application of sensitivity and uncertainty analysis techniques: lessons learned with two agricultural system models. ASA-CSSA-SSSA Annual Meeting Abstracts. Oct. 31 - Nov. 4 2004.

Practical Application of Sensitivity and Uncertainty Analysis Techniques: Lessons Learned with Two Agricultural System Models - (Abstract)

Ascough Ii, J.C., Ma, L. 2004. Practical application of sensitivity and uncertainty analysis techniques: lessons learned with two agricultural system models. Meeting Abstract. www.asa-cssa-ssa.org/anmeet. Seattle, WA. Oct.31-11/4/2004.

Simulating Planting Date Effects on Corn Production Using Rzwqm and Ceres-Maize - (Peer Reviewed Journal)

Saseendran, S.A., Ma, L., Nielsen, D.C., Vigil, M.F., Ahuja, L.R. 2005. Simulating planting date effects on corn production using RZWQM and CERES-Maize Models. Agronomy Journal. 97:58-71 (2005).

Predicting Pesticide Transport in Mulch Amended Soils: a Two-Compartment Model - (Peer Reviewed Journal)

Ma, L., Selim, H.M. 2005. Predicting pesticide transport in mulch amended soils: a two-compartment model. Soil Science Society of America Journal. 69:318-327. 2005.

Model Parameters for Agricultural Systems with Nonlinear Process Interations and Spatial Variability - (Abstract)

Green, T.R., Ahuja, L.R., Ascough II, J.C., Ma, L., Erskine, R.H., McMaster, G.S. 2004. Model parameters for agricultural systems with nonlinear process interations and spatial variability. Agronomy Abstracts a04-5627. (CD-ROM). 2004.

A Graphical Tool for Water Quality Conservation Planning 1718 - (Proceedings/Symposium)

Heilman, P., Armendariz, G.A., Ma, L., Malone, R.W. 2004. A graphical tool for water quality conservation planning. Proc. 13th Internat'l. Soil Conservation Org. Conf., Conserving Soil and Water for Soc.: Sharing Solutions, July 2004, Brisbane, Australia, 6 p.

Role of Macropores in Pesticide Transport to Groundwater - (Proceedings/Symposium)

Malone, R.W., Shipitalo, M.J., Ma, L., Ahuja, L.R., Rojas, K.W., Logsdon, S.D., Weatherington-Rice, J. 2004. Role of macropores in pesticide transport to groundwater. International Workshop on Applications, Enhancements, and Collaborations of ARS RZWQM and GPFARM Models. p. 39-40.

Agricultural Management Effects on Crop Production and N Losses to Tile Drainage in the Nashua Study: Simulation Results with Rzwqm - (Abstract)

Ma, L., Malone, R.W., Heilman, P., Anapalli, S., Ahuja, L.R., Kanwar, R.S. 2004. Agricultural management effects on crop production and n losses to tile drainage in the nashua study: simulation results with rzwqm. International Workshop on applications, enhancements and collaborations of ARS RZWQM and GPFARM. April 20-22, 2004. Fort Collins. pp. 14-15.

Using Rzwqm to Simulate Water, Nitrogen, and Planting Date Effects on Corn, Soybean, and Winter Wheat Production in Northeast Colorado - (Proceedings/Symposium)

Nielsen, D.C., Ma, L., Anapalli, S., Ahuja, L.R. 2004. Using RZWQM to simulate water, nitrogen, and planting date effects on corn, soybean, and winter wheat production in Northeast Colorado. International Workshop on Application, Enhancements and Collaborations of ARS RZQWM Models, Fort Collins, CO, April 20-22, 2004. p. 24-25.

Agricultural System Models in Field Research and Technology Transfer - (Proceedings/Symposium)

Ahuja, L.R., Ma, L., Andales, A.A., Saseendran, S.A. 2004. Agricultural system models in field research and technology transfer. Second International Agronomy Congress Proceedings. Punjab Singh, I.P.S. Ahlawat and R.C. Gautam (eds.) Indian Society of Agronomy. pp. 226-233.

Modeling Alternative Cropping Systems for Central Great Plains Using Rzwqm - (Proceedings/Symposium)

Anapalli, S.S., Nielsen, D.C., Ma, L., Ahuja, L.R., Vigil, M.F., Benjamin, J.G. 2004. Modeling alternative cropping systems for central great plains using RZWQM. Proceedings of the International Workshop on Applications, Enhancements and Collaborations of ARS RZWQM and GPFARM Models. April 20-22, 2004. p.22-23.

Model Parameterization at Different Scales: How Do We Estimate and Incorporate Spatial Information? - (Abstract)

Green, T.R., Ascough Ii, J.C., Ahuja, L.R., Ma, L., Erskine, R.H. 2004. Model parameterization at different scales: how do we estimate and incorporate spatial information?. Intl. Workshop on Applications, Enhancements and Collaboration of ARS RZWQM and GPFARM Models, April 20-22, 2004, Fort Collins, CO.

The Future of Spatial Modeling at Gpsru - (Abstract)

Ascough Ii, J.C., Green, T.R., Ahuja, L.R., Mcmaster, G.S., Ma, L. 2004. The future of spatial modeling at GPSRU. Workshop Proceedings. Intl. Workshop on Applications, Enhancements, and Collaboration of ARS RZWQM and GPSFARM Models, April 20 - 22, 2004, Fort Collins, CO.

Space-Time Modeling of Agricultural Landscape Variability Using Agsimgis - (Proceedings/Symposium)

Ascough Ii, J.C., Green, T.R., Cipra, J.E., Ahuja, L.R., Ma, L. 2004. Space-time modeling of agricultural landscape variability using agsimgis. Annual Hydrology Days Conference Proceedings. March 10-12, 2004. Fort Collins, CO. pp. 10-21.

Book Review: Mathematical Modeling for System Analysis in Agricultural Research by Karel D. Vohnout - (Literature)

Ma, L., Ahuja, L.R. 2004. Book review: mathematical modeling for system analysis in agricultural research by karel d. vohnout. Agricultural Systems. Vol 81, pp. 273-274.

Using Rzwqm to Predict Herbicide Leaching Losses in Subsurface Drainage Water - (Peer Reviewed Journal)

Bakhsh, A., Ma, L., Ahuja, L.R., Hatfield, J.L., Kanwar, R.S. 2004. Using rzwqm to predict herbicide leaching losses in subsurface drainage water. Agricultural Systems. Vol 47(5):1415-1426. 2004.

Simulating Swine Manure Effects on N Leaching and Crop Production - (Abstract)

MA, L., MALONE, R.W., ANAPALLI, S.A., MEADE, T.G., KANWAR, R.S., KARLEN, D.L., HATFIELD, J.L., AHUJA, L.R. SIMULATING SWINE MANURE EFFECTS ON N LEACHING AND CROP PRODUCTION. CD-ROM. MADISON, WI. AMERICAN SOCIETY OF AGRONOMY MEETINGS. 2003.

Simulating Late Spring Nitrogen Test Effects on N Leaching and Crop Production - (Abstract)

MALONE, R.W., MEADE, T.G., MA, L., ANAPALLI, S.A., KANWAR, R.S., KARLEN, D.L., HATFIELD, J.L., AHUJA, L.R. SIMULATING LATE SPRING NITROGEN TEST EFFECTS ON N LEACHING AND CROP PRODUCTION. CD-ROM. MADISON, WI. AMERICAN SOCIETY OF AGRONOMY MEETINGS. 2003.

Test of the Root Zone Water Quality Model (Rzwqm) for Predicting Runoff of Atrazine, Alachlor and Fenamiphos Species from Conventional-Tillage Corn Mesoplots - (Peer Reviewed Journal)

Ma, Q.L., Wauchope, R.D., Ma, L., Rojas, K.W., Malone, R.W., Ahuja, L.R. 2004. Test of the root zone water quality model (rzwqm) for predicting runoff of atrazine, alachlor and fenamiphos species from conventional-tillage corn mesoplots. Pest Management Science 60:267-276(2004).

Herbicide Leaching As Affected by Macropore Flow and Within-Storm Rainfall Intensity Variation: a Rzwqm Simulation - (Peer Reviewed Journal)

Malone, R.W., Weatherington-Ric, J., Shipitalo, M.J., Fausey, N.R., Ma, L., Ahuja, L.R., Wauchope, R.D., Ma, Q. 2004. Herbicide leaching as affected by macropore flow and within-storm rainfall intensity variation: a RZWQM simulation. Pest Management Science. 60:277-285.

Modeling Hydrology, Metribuzin Degradation, and Metribuzin Transport in Macroporous Tilled and No-Till Silt Loam Soil Using Rzwqm - (Peer Reviewed Journal)

Malone, R.W., Ma, L., Wauchope, R.D., Ahuja, L.R., Rojas, K.W., Ma, Q., Warner, R., Byers, M. 2004. Modeling hydrology, metribuzin degradation, and metribuzin transport in macroporous tilled and no-till silt loam soil using RZWQM. Pest Management Science. 60:253-266.

Book Review: Crop-Soil Simulation Models: Applications in Developing Countries - (Literature)

Saseendran, S.A., Ahuja, L.R., Ma, L. 2003. Book review: crop-soil simulation models: applications in developing countries. Journal of Environmental Quality. Vol 32, pp. 2445-2446.

Modeling Nitrogen Management Effects on Winter Wheat Production Using Rzwqm and Ceres-Wheat - (Peer Reviewed Journal)

Saseendran, S.A., Nielsen, D.C., Ma, L., Ahuja, L.R., Halvorson, A.D. 2003. Modeling nitrogen management effects on winter wheat production using RZWQM and CERES-Wheat. Agronomy Journal 96:615-630.

Evaluation of Rzwqm under Varying Irrigation Levels in Eastern Colorado - (Peer Reviewed Journal)

MA, L., NIELSEN, D.C., AHUJA, L.R., MALONE, R.W., ANAPALLI, S.S., ROJAS, K.W., HANSON, J.D., BENJAMIN, J.G. EVALUATION OF RZWQM UNDER VARYING IRRIGATION LEVELS IN EASTERN COLORADO. TRANSACTIONS OF THE AMERICAN SOCIETY OF AGRICULTURAL ENGINEERS. 2002. v. 46. p. 39-49.

Predicting the Effects of Agricultural Management Practices on Subsurface Drainage: Nitrate - (Abstract)

MA, L., MALONE, R.W., AHUJA, L.R., KANWAR, R.S. PREDICTING THE EFFECTS OF AGRICULTURAL MANAGEMENT PRACTICES ON SUBSURFACE DRAINAGE: NITRATE. AMERICAN SOCIETY OF AGRONOMY MEETINGS. 2002. CD-ROM. MADISON, WI.

Predicting the Effects of Agricultural Management Practices on Subsurface Drainage: Tile Flow - (Abstract)

MALONE, R.W., MA, L., AHUJA, L.R., KANWAR, R.S. PREDICTING THE EFFECTS OF AGRICULTURAL MANAGEMENT PRACTICES ON SUBSURFACE DRAINAGE: TILE FLOW. AMERICAN SOCIETY OF AGRONOMY MEETINGS. 2002. CD-ROM. MADISON, WI.

Use of Limited Soil Property Data and Modeling to Estimate Root Zone Soil Water Content. - (Peer Reviewed Journal)

STARKS, P.J., HEATHMAN, G.C., AHUJA, L.R., MA, L. USE OF LIMITED SOIL PROPERTY DATA AND MODELING TO ESTIMATE ROOT ZONE SOIL WATER CONTENT.. JOURNAL OF HYDROLOGY. 2003. v. 272 p. 131-147.

Topographic Analysis, Scaling and Models to Evaluate Spatial/temporal Variability of Landscape Processes and Management - (Book/Chapter)

Ahuja, L.R., Green, T.R., Erskine, R.H., Ma, L., Ascough Ii, J.C., Dunn, G.H., Shaffer, M.J., Martinez, A. 2002. Topographic analysis, scaling and models to evaluate spatial/temporal variability of landscape processes and management. CRC Book: Agricultural Sys Models in Field Research and Technology Transfer. April 2002. Chapter 13, pp 265-272.

Evaluation of Root Zone Water Quality Model for Simulation of Nonpoint Source Pollution from Agricultural Lands - (Proceedings/Symposium)

BAKHSH, A., HATFIELD, J.L., KANWAR, R.S., MA, L., AHUJA, L.R. EVALUATION OF ROOT ZONE WATER QUALITY MODEL FOR SIMULATION OF NONPOINT SOURCE POLLUTION FROM AGRICULTURAL LANDS. ASAE ANNUAL INTERNATIONAL MEETING. 2001. CD-ROM. MADISON, WI.