Nutrients and water quality

Extension Publications

• Agricultural Nitrogen Management for Water Quality Protection in the Midwest
• Agricultural Phosphorus Management and Water Quality Protection in the Midwest
• CROP 3104 Answering common producer questions on cover crop use in Iowa
• SP 0435A Reducing Nutrient Loss: Science Shows What Works
• 4R Phosphorus Management Practices for Major Commodity Crops of North America

Presentations

• Environmental P management and the Iowa P Index. A.P. Mallarino. 2020. Soil fertility and nutrient management short course. Iowa State University Extension and Outreach, Ames.
• Nitrogen and water week

Newsletter Articles

View newsletter articles 2015 and earlier -- click here to expand

• Surface waters: ammonium is not ammonia - part 3 (5/2008)
• Surface waters: ammonium is not ammonia - part 2 (5/2008)
• Surface waters: ammonium is not ammonia - part 1 (4/2008)

Conference Proceedings and Reports

• Mallarino, A.P, M.U. Haq, and L.B. Thompson. 2023. Reducing dissolved and total phosphorus loss with surface runoff by using gypsum as a soil amendment. Final Project Report to Calcium Products Inc. and The Leopold Center for Sustainable Agriculture.
• Mallarino, A.P., M.U. Haq, and M.J. Helmers. 2022. Phosphorus placement and application time strategies to reduce dissolved phosphorus loss with surface runoff in no-till corn-soybean rotations. Final project report to the Iowa Nutrient Research Center.
• Mallarino, A.P., M.U. Haq, M.J. Helmers, et al. 2022. Impacts of cover crops on phosphorus and nitrogen loss with surface runoff: A six-year field-scale study. Final project report to the Iowa Nutrient Research Center.
• Mallarino, A.P., M.U. Haq, J.D. Jones, and M.J. Helmers. 2021. Management of fertilizer, manure, tillage, cover crop, and alum or gypsum soil amendments to minimize dissolved P loss from corn and soybean fields. p. 53-59. In 32nd Integrated Crop Management Conf. Proceedings. 1-2 Dec. Iowa State Univ. Extension.
• Gomez-Botero, M., A.P. Mallarino, M.U. Haq, M.L. Thompson, and J.E. Sawyer. 2020. Evaluation of plant-available phosphorus of dried residuals from wastewater processed for phosphorus reduction with aluminum or iron. In 50th North-Central Extension-Industry Soil Fertility Conf. Proceedings. Nov. 18-19.
• Dougherty, B., C. Pederson, M. Helmers, M. Soupir, D. Andersen, A.P. Mallarino, and J. Sawyer. 2020. Effect of manure application timing and cover crops on nitrogen and phosphorus leaching in 2016–2019. Iowa State Univ. Research and Demonstration Farms Progress Reports 2019. RFR-A1966.
• Mallarino, A.P., M.U. Haq, J. Sievers, and T. Tuttle. 2019. Soil and phosphorus losses with surface runoff from corn-soybean rotations as affected by tillage, cover crops, and phosphorus placement methods. Iowa State Univ. Research and Demonstration Farms Progress Reports 2018. RFR-A1868.
• Dougherty, B., C. Pederson, M. Helmers, M. Soupir, D. Andersen, A.P. Mallarino, and J. Sawyer. 2019. Partial nitrogen and phosphorus balance in drainage water quality plots, 2008–2015. Iowa State Univ. Research and Demonstration Farms Progress Reports 2018. RFR-A1895.
• Dougherty, B., C. Pedersen, D. Andersen, M. Helmers, and A.P. Mallarino. 2018. The impact of manure management and cover crops on drainage water quality and yields. p. 101-107. In 30th Integrated Crop Management Conf. Proceedings. Nov. 28-29, 2018. Iowa State Univ. Extension.
• Dougherty, B., C. Pederson, M. Helmers, M. Soupir, D. Andersen, A.P. Mallarino; and J. Sawyer. 2017. Drainage water quality impacts of agricultural management practices: effect of manure application timing and cover crops. Farm Progress Reports: Vol. 2016: Iss. 1, Article 65.
• Dougherty, B., C. Pederson, M. Helmers, M. Soupir, R. Kanwar, and A.P. Mallarino. 2017. Impact of liquid swine manure application and cover crops on dissolved phosphorus in subsurface drainage water. Farm Progress Reports: Vol. 2016: Iss. 1, Article 71.

View conference proceedings and reports 2016 and earlier -- click here to expand

• Mallarino, A.P., and M.U. Haq. 2016. How can fertilizer and manure management practices reduce dissolved phosphorus loss from fields and improve water quality? p. 179-184. In The Integrated Crop Management Conf. Proceedings. Nov. 30-Dec. 1, 2016. Iowa State Univ. Extension.
• Pederson, C., M. Helmers, R. Kanwar, and A.P. Mallarino, 2016. Impact of liquid swine manure application and cover crops on nitrate in subsurface drainage water. Northeast Research and Demonstration Farm Annual Reports. ISRF15-13, RFR-A1596. Iowa State Univ., Ames, IA.
• Pederson, C., M. Helmers, M. Soupir, R. Kanwar, and A.P. Mallarino. 2015. Impact of liquid swine manure application and cover crops on nitrate in subsurface drainage water. Northeast Research and Demonstration Farm Annual Reports. ISRF14-13, RFR-A1491. Iowa State Univ., Ames, IA.
• Mallarino, A.P., and M.U. Haq. 2015. Phosphorus loss with runoff after applying fertilizer or manure as affected by the timing of rainfall. p. 94-99. In 45th North-Central Extension-Industry Soil Fertility Conf. Proceedings. Nov. 4-5, 2015. Vol. 31. Des Moines, IA. International Plant Nutrition Institute, Brookings, SD.
• Mallarino, A.P. 2014. Using precision agriculture technologies for phosphorus, potassium, and lime management with lower grain prices and to improve water quality. p. 137-143. In The Integrated Crop Management Conf. Proceedings. Dec. 3-4, 2014. Iowa State Univ. Extension.
• Mallarino, A.P., M.U. Haq, M.J. Helmers, J. Sievers, and R. Rusk. 2013. Effects of tillage and phosphorus source on long-term phosphorus runoff loss and crop yield. Northwest Research Farm and Allee Demonstration Farm Annual Reports. ISRF12-29, 31. Iowa State Univ., Ames, IA.
• Mallarino, A.P. 2013. Optimizing yield while minimizing phosphorus water quality impacts: Some do’s and don’ts. p. 165-173. In The Integrated Crop Management Conf. Proceedings. Dec. 4-5, 2013. Iowa State Univ. Extension.
• Mallarino, A.P., and M.U. Haq. 2012. Alum and gypsum treated poultry manure and fertilizer phosphorus losses with runoff with or without incorporation into the soil. Final project report to the Iowa Egg Council.
• Helmers, M.J., R.D. Christianson, and J. Sawyer. 2011.  Nitrate loss in subsurface drainage as affected by nitrogen application rate and timing under a corn-soybean rotation. p. 123-128. In Proc. 23rd Annual Integrated Crop Manag. Conf., Ames, IA. 1 Nov-2 Dec. 2011. Iowa State Univ., Ames, IA.
• Mallarino, A.P., M.U. Haq, M.J. Helmers, A.A. Andrews, C.H. Pederson, and R.E. Rusk. 2010. Tillage, cropping, harvest, and nutrient management systems impacts on phosphorus loss with surface runoff: A research update. p. 171-180. In The Integrated Crop Management Conf. Proceedings. Dec. 1-2, 2010. Ames, IA. Iowa State Univ. Extension.
• Sawyer, J.E., and G.W. Randall. 2008. Nitrogen rates, p. 59-71. In G. Laing (ed.) Final Report: Gulf Hypoxia and Local Water Quality Concerns Workshop. Upper Mississippi Sub-basin Hypoxia Nutrient Committee, Ames, IA. 26-28 Sep. 2005. ASABE, St. Joseph, MI.
• Randall, G.W., and J.E. Sawyer. 2008. Nitrogen application timing, forms and additives.  p. 73-85. In G. Laing (ed.) Final Report: Gulf Hypoxia and Local Water Quality Concerns Workshop. Upper Mississippi Sub-basin Hypoxia Nutrient Committee, Ames, IA. 26-28 Sep. 2005. ASABE, St. Joseph, MI.
• Pedersen, P., J. Sawyer, D. Barker, D. Ruiz Diaz, and J. Stuart. 2008. Educating growers about living mulch systems for grain crop production. Final project report to the Iowa Department of Agriculture and Land Stewardship, Division of Soil Conservation, IFLM program.
• Mallarino, A.P., and M.U. Haq. 2007. On-farm demonstration of the impact of phosphorus soil-test levels and management on phosphorus loss with surface runoff. Final progress report for water quality project.
• Mallarino, A.P., J.E. Sawyer, D. Kaiser, D. Ruiz-Diaz, B. Allen, D. Barker, and D. Wittry. 2007. Demonstration of agronomic and environmentally sound utilization of nitrogen and phosphorus in poultry manure. Final project report to the Iowa Department of Agriculture and Land Stewardship, Division of Soil Conservation, IFLM program.
• Mallarino, A.P., and D. Wittry. Pilot implementation of an environmental phosphorus assessment tool for Iowa. Final project report to the Iowa Department of Natural Resources, 319 Program.
• Mallarino, A.P., B.L. Allen, and M.U. Haq. 2005. Manure management impacts on phosphorus loss with surface runoff and on-farm phosphorus index implementation. An overview of ongoing research. In Agriculture and the Environment Conf. Proceedings [CD-ROM]. March 8-9, 2005. Iowa State Univ. Extension, Ames, IA.
• Mallarino, A.P., M.U. Haq, and K. Pecinovsky. 2005. Runoff phosphorus loss as affected by tillage, fertilizer, and swine manure phosphorus management in corn-soybean production systems. p. 46-47. In Annual progress reports-2004. Northeast research and demonstration farm. ISRF04-13. Iowa State Univ., Ames, IA.
• Kanwar, R., J. Baker, C. Pederson, A.P. Mallarino, J. Sawyer, and K. Pecinovsky. 2004. Impact of swine manure applications on nitrate and phosphorus in subsurface drainage water. p. 26-27. In Annual progress reports-2003. Northeast research and demonstration farm. ISRF03-13. Iowa State Univ., Ames, IA.
• Baker, J.L. 2004. Limitations of improved nitrogen management to reduce leaching and increase use efficiency. In Proc. Optimizing Nitrogen Management in Food and Energy Production and Environmental Protection, 2nd International Nitrogen Conf. on Science and Policy. The Scientific World 1(S2), 10-16.
• Baker, J.L. 2004. In-field nutrient availability and balances, and potential implications on management systems to reduce losses. In Proc. Agriculture and the Environment Conf. 1-2 March. Iowa State Univ., Ames, IA
• Kanwar, R., C. Pederson, J. Baker, A.P. Mallarino, J. Sawyer, and K. Pecinovsky. 2003. Fertilizer and swine manure management systems: Impacts on crop production and nitrate-nitrogen leaching with subsurface drainage. Annual progress reports-2002. Northeast Research and Demonstration farm. ISRF02-13. Iowa State Univ., Ames, IA.
• Mallarino, A.P., J. Sawyer, J. Klatt, R. Kanwar, C. Pederson, J. Baker, and K. Pecinovsky. 2003. Fertilizer and swine manure management systems: impacts on agronomic and environmental soil phosphorus tests and on phosphorus loss with subsurface drainage. Annual progress reports-2002. Northeast Research and Demonstration farm. ISRF02-13. Iowa State Univ., Ames, IA.
• Mallarino, A.P. 2003. Using the Iowa phosphorus index for agronomic and environmental management of fertilizer and manure phosphorus. p. 121-126. In The Integrated Crop Management Conf. Proceedings. Dec. 3-4, Ames, IA. Iowa State Univ. Extension.
• Klatt, J.G., A.P. Mallarino, and B.L. Allen. 2002. Relationships between soil phosphorus and phosphorus in surface runoff and subsurface drainage. An overview of ongoing research. p. 183-189. In North-Central Extension-Industry Soil Fertility Conf. Proceedings. Vol. 18. Des Moines, IA.
• Wittry, D.J., and A.P. Mallarino. 2002. Use of variable-rate technology for agronomic and environmental phosphorus-based liquid swine manure management. In P.C. Robert et al. (ed.). Sixth Intl. Conf. on Site-Specific Management for Agricultural Systems. Proceedings. CD-ROM. July14-17. Minneapolis, MN. ASA, CSSA, SSSA, Madison, WI.
• Mallarino, A.P., D. Wittry, and J. Klatt. 2001. Using the Iowa phosphorus index and variable-rate technology for effective agronomic and environmental phosphorus management. p. 151-158. In The Integrated Crop Management Conf. Proceedings. Dec. 5-6, 2001, Ames, IA. Iowa State Univ. Extension.

Featured

Links

• Iowa NRCS Phosphorus Index
• Iowa Nutrient Reduction Strategy
• SERA 17 - Minimizing Phosphorus Losses from Agriculture
• Water Quality (Iowa State University)
• Questions and Answers Regarding Nitrogen and Water Quality

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