Coordinated Site Network for Studying the Impacts of 4R Nutrient Management on Crop Production and Nutrient Loss

Crops: Corn for grain, Corn for silage
4R Practices: Source, Rate, Time, Place

Project Summary

Currently, there is a concerted effort from industry, universities, and state and federal action agencies to promote the 4R nutrient management approach on-farm– considering the Right source, Right rate, Right time, and Right place– for managing nutrient additions from commercial fertilizer and organic materials. With its massive acreage and intensive nutrient use, corn production systems are an important focus of the 4R program. To convince farmers to adopt the 4R approach, and to ensure that production, soil health, and environmental goals are realized, there is a critical need for field research that measures responses to 4R management systems across a range of soils and agro-ecosystems within the main corn producing areas of North America. Limited research data linking agronomic and environmental performance of 4R practices across a wide variety of conditions is a critical research gap leading to high uncertainty regarding practice efficacy for both farmers and environmental program and policy decision makers. Along with production and soil health effects, full accounting of the multiple forms and pathways of nitrogen (N) and phosphorus (P) is essential to understand the environmental consequences of current and advanced best nutrient practices. A thorough accounting of the N balance could also serve as an early warning for practices that are improving or reducing soil carbon and thus soil health because soil carbon-nitrogen interactions dramatically impact soil organic matter accumulation and carbon sequestration. Further, potassium (K) nutrition of crops has attracted renewed attention, and although not of environmental concern, K requirements of crops are nearly the same as those of N, and cannot be ignored. We propose the creation of a coordinated field site network strategically distributed across the cornbelt with unique infrastructure that would collect similar agronomic and environmental measures thereby enabling for the first time knowledge synthesis across varied soils, climates, and management systems. Quantification of the impacts of 4R management on crop yield, P, K, and nitrate (NO3) losses in water, N losses to the atmosphere, and changes in soil health at the same location under a range of management practices is severely lacking. In addition, we are aware of no studies explicitly aimed at understanding the interactions between 4R management strategies and soil health.

Project Goals:

• Quantify the impact of 4R Nutrient Stewardship on crop yield, soil health, nutrient use efficiencies, nutrient losses with leaching, and gaseous nitrogen losses across a network of coordinated studies in the major corn producing area of North America.

Project Results:

• Preliminary nitrogen balance assessments indicated a -15 to -17 lb N/ac balance while optimizing corn yields when injecting N fertilizer for one study year averaged across all sites.
• Corn-soybean rotations in the study resulted in a 10 to 24 lb N/ac lower nitrogen balance than a continuous corn system.
• Conventional tillage resulted in greater corn yield with a reduced nitrogen balance of 4 to 7 lb N/ac compared to reduced tillage, however, the amount of nitrate loss in tile drainage was 9 to 13 lb N/ac greater with more intensive tillage.

Reports

2017 – Annual Report

Final Report

Publications

• Andino LF, Gentry LE, Fraterrigo JM. Closed depressions and soil phosphorus influence subsurface phosphorus losses in a tile-drained field in Illinois. J. Environ. Qual. 2020; 49: 1273–1285. https://doi.org/10.1002/jeq2.20120
• Gentry, L. E., Green, J. M., Mitchell, C. A., Andino, L. F., Rolf, M. K., Schaefer, D., & Nafziger, E. D. (2024). Split fertilizer nitrogen application with a cereal rye cover crop reduces tile nitrate loads in a corn–soybean rotation. Journal of Environmental Quality, 53, 90–100. https://doi.org/10.1002/jeq2.20530
• Alves de Oliveira, L., Muñoz Ventura, A., Preza-Fontes, G., Greer, K. D., Pittelkow, C. M., Bhattarai, R., Christianson, R., & Christianson, L. (2022). Assessing the concept of control points for dissolved reactive phosphorus losses in subsurface drainage. Journal of Environmental Quality, 51, 1155–1167. https://doi.org/10.1002/jeq2.20400
• Preza-Fontes, G., Christianson, L. E., & Pittelkow, C. M. (2023). Investigating tradeoffs in nitrogen loss pathways using an environmental damage cost framework. Agricultural & Environmental Letters, 8, e20103. https://doi.org/10.1002/ael2.20103
• Preza-Fontes, G., Pittelkow, C. M., Greer, K. D., Bhattarai, R., Christianson, L. E. (2021). Split-nitrogen application with cover cropping reduces subsurface nitrate losses while maintaining corn yields. J Environ Qual. 50: 1408–1418. https://doi.org/10.1002/jeq2.20283
• Preza-Fontes, G., Christianson, L. E., Greer, K., Bhattarai, R., & Pittelkow, C. M. (2022). In-season split nitrogen application and cover cropping effects on nitrous oxide emissions in rainfed maize. Agriculture, Ecosystems and Environment, 326. https://doi.org/10.1016/j.agee.2021.107813
• Preza Fontes, G., Bhattarai, R., Christianson, L. E., & Pittelkow, C. M. (2019). Combining Environmental Monitoring and Remote Sensing Technologies to Evaluate Cropping System Nitrogen Dynamics at the Field-Scale. Frontiers in Sustainable Food Systems, 3. https://doi.org/10.3389/fsufs.2019.00008
• Crespo, C., O’Brien, P. L., Nunes, M. R., Ruis, S. J., Emmett, B. D., Rogovska, N., Malone, R. W., Cambardella, C., & Kovar, J. L. (2024). Contrasting soil management systems had limited effects on soil health and crop yields in a North Central US Mollisol. Soil Science Society of America Journal, 88, 1723–1735. https://doi.org/10.1002/saj2.20716
• Emmett, B. D., O’Brien, P. L., Malone, R. W., Rogovska, N., Kovar, J. L., Kohler, K., Kaspar, T. C., Moorman, T. B., Jaynes, D. B., & Parkin, T. B. (2022). Nitrate losses in subsurface drainage and nitrous oxide emissions from a winter camelina relay cropping system reveal challenges to sustainable intensification. Agriculture, Ecosystems and Environment, 339. https://doi.org/10.1016/j.agee.2022.108136
• Kovar, J. L., Papanicolaou, A. N., Busch, D. L., Chatterjee, A., Cole, K. J., Dalzell, B. J., Emmett, B. D., Johnson, J. M. F., Malone, R. W., Morrow, A. J., Nowatzke, L. W., O’Brien, P. L., Prueger, J. H., Rogovska, N., Ruis, S. J., Todey, D. P., & Wacha, K. M. (2024). The LTAR Cropland Common Experiment at Upper Mississippi River Basin–Ames. Journal of Environmental Quality, 53, 978–988. https://doi.org/10.1002/jeq2.20646
• O’Brien, P. L., Emmett, B. D., Malone, R. W., Nunes, M. R., Kovar, J. L., Kaspar, T. C., Moorman, T. B., Jaynes, D. B., & Parkin, T. B. (2022). Nitrate losses and nitrous oxide emissions under contrasting tillage and cover crop management. Journal of Environmental Quality, 51, 683–695. https://doi.org/10.1002/jeq2.20361
• Rogovska, N., Kovar, J. L., Malone, R., O’Brien, P., Emmett, B., & Ruis, S. J. (2025). Impact of tillage, cover crop, and in situ bioreactors on nutrient loss from an artificially drained Midwestern Mollisol. Journal of Environmental Quality, 54, 590–604. https://doi.org/10.1002/jeq2.20668
• Rogovska, N., O’Brien, P. L., Malone, R., Emmett, B., Kovar, J. L., Jaynes, D., Kaspar, T., Moorman, T. B., & Kyveryga, P. (2023). Long-term conservation practices reduce nitrate leaching while maintaining yields in tile-drained Midwestern soils. Agricultural Water Management, 288, 108481. https://doi.org/10.1016/J.AGWAT.2023.108481
• Kaur, H., & Nelson, K. A. (2024). Subsurface Drainage and Nitrogen Fertilizer Management Affect Fertilizer Fate in Claypan Soils. Sustainability (Switzerland), 16(15). https://doi.org/10.3390/su16156477
• Kaur, H., Nelson, K. A., Singh, G., & Kaur, G. (2024). Subsurface drainage and nitrogen management affects corn and soybean yield in claypan soils in upstate Missouri. Agronomy Journal, 116, 153–169. https://doi.org/10.1002/agj2.21514
• Kaur, H., Nelson, K. A., Udawatta, R., & Kaur, G. (2024). Subsurface drainage and nitrogen management affects soil properties in upstate Missouri U.S. Geoderma Regional, 39, e00888. https://doi.org/10.1016/J.GEODRS.2024.E00888
• Waring, E. R., Sawyer, J., Pederson, C., & Helmers, M. (2022). Impact of nitrogen fertilizer timing on nitrate loss and crop production in northwest Iowa. Journal of Environmental Quality, 51, 696–707. https://doi.org/10.1002/jeq2.20366
• Sawyer, J., Helmers, M., Pederson, C. & Tuttle, T., (2019) “Impact of 4R Management on Crop Production and Nitrate-Nitrogen Loss in Tile Drainage”, Iowa State University Research and Demonstration Farms Progress Reports 2018(1). https://www.iastatedigitalpress.com/farmreports/article/id/502/
• Waring, E., Pederson, C. H., Helmers, M. J., Sawyer, J. E. & Tuttle, T., (2020) “Impact of 4R Management on Crop Production and Nitrate-Nitrogen Loss in Tile Drainage”, Iowa State University Research and Demonstration Farms Progress Reports 2019(1). https://www.iastatedigitalpress.com/farmreports/article/id/11366/
• Drury, C. F., Agomoh, I. V., Yang, X., Phillips, L. A., Reynolds, W. D., Helmers, M. J., Calder, W., & Hedge, T. (2024). Stacking nitrogen management practices: Combining double-slot fertilizer injection with urease and nitrification inhibitors improves yields and reduces ammonia and nitrous oxide emissions. Soil Science Society of America Journal, 88, 1309–1323. https://doi.org/10.1002/saj2.20677
• Preza-Fontes G, Nafziger ED, Christianson LE, Pittelkow CM. Relationship of in-season soil nitrogen concentration with corn yield and potential nitrogen losses. Soil Sci. Soc. Am. J. 2020; 84: 1296–1306. https://doi.org/10.1002/saj2.20117
• Menegaz, S.T., Fernández, F.G., Venterea, R.T., Helmers, M.J., Pagliari, P.H. (2025). Nitrate, Nitrous Oxide, and Ammonia Loss Mitigation with Optimum Rate of Enhanced Efficiency Nitrogen Fertilizer and Application Timing in Corn. In: Hatano, R., Baggs, E.M. (eds) Nitrogen Cycling and Soil Health. NCSH 2022. Progress in Soil Science. Springer, Singapore. https://doi.org/10.1007/978-981-96-1132-4_2
• Drury CF, Reynolds WD, Yang X, McLaughlin NB, Calder W, & Phillips LA. Diverse rotations impact microbial processes, seasonality and overall nitrous oxide emissions from soils. Soil Sci Soc Am J. 2021; 85: 1448–1464. https://doi.org/10.1002/saj2.20298
• Woodley, A.L., Drury, C.F., Reynolds, W.D., Tan, C.S., Yang, X.M. and Oloya, T.O. (2018), Long-term Cropping Effects on Partitioning of Water Flow and Nitrate Loss between Surface Runoff and Tile Drainage. J. Environ. Qual., 47: 820-829. https://doi.org/10.2134/jeq2017.07.0292
• Woodley AL, Drury CF, Yang XY, et al. Ammonia volatilization, nitrous oxide emissions and corn yields as influenced by nitrogen placement and enhanced efficiency fertilizers. Soil Sci. Soc. Am. J. 2020; 84: 1327–1341. https://doi.org/10.1002/saj2.20079