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ARS Home » Midwest Area » West Lafayette, Indiana » National Soil Erosion Research Laboratory » Research » Publications at this Location » Publication #387603

Research Project: Conservation Practice Impacts on Water Quality at Field and Watershed Scales

Location: National Soil Erosion Research Laboratory

Title: Uncertainty in phosphorus fluxes and budgets across the U.S. long-term agroecosystem research network

item WELIKHE, PAULINE - Purdue University
item Williams, Mark
item King, Kevin
item Bos, Janae
item AKLAND, MARK - University Of Kentucky
item Baffaut, Claire
item BECK, GLYNN - University Of Kentucky
item Bierer, Andrew
item Bosch, David - Dave
item BROOKS, ERIN - University Of Idaho
item Buda, Anthony
item Cavigelli, Michel
item FAULKNER, JOSHUA - University Of Vermont
item Feyereisen, Gary
item Fortuna, Ann Marie
item Gamble, Joshua
item Hanrahan, Brittany
item HUSSAIN, MIR ZAMAN - Michigan State University
item Kovar, John
item LEE, BRAD - University Of Kentucky
item Leytem, April
item Liebig, Mark
item LINE, DANIEL - North Carolina State University
item MACRAE, MERRIN - University Of Waterloo
item Moorman, Thomas
item Moriasi, Daniel
item MUMBI, ROSE - Purdue University
item NELSON, NATHAN - Kansas State University
item ORTEGA-PIECK, ALINE - University Of Idaho
item OSMOND, DEANA - North Carolina State University
item Penn, Chad
item Pisani, Oliva
item Reba, Michele
item Smith, Douglas
item UNRINE, JASON - University Of Kentucky
item WEBB, PEARL - University Of Arkansas
item White, Kathryn
item WILSON, HENRY - Agriculture And Agri-Food Canada
item Witthaus, Lindsey

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/21/2023
Publication Date: 5/5/2023
Citation: Welikhe, P., Williams, M.R., King, K.W., Bos, J.H., Akland, M., Baffaut, C., Beck, G., Bierer, A.M., Bosch, D.D., Brooks, E., Buda, A.R., Cavigelli, M.A., Faulkner, J., Feyereisen, G.W., Fortuna, A., Gamble, J.D., Hanrahan, B.R., Hussain, M., Kovar, J.L., Lee, B., Leytem, A.B., Liebig, M.A., Line, D., Macrae, M., Moorman, T.B., Moriasi, D.N., Mumbi, R., Nelson, N., Ortega-Pieck, A., Osmond, D., Penn, C.J., Pisani, O., Reba, M.L., Smith, D.R., Unrine, J., Webb, P., White, K.E., Wilson, H., Witthaus, L.M. 2023. Uncertainty in phosphorus fluxes and budgets across the U.S. long-term agroecosystem research network. Journal of Environmental Quality. 52(4):837-885.

Interpretive Summary: Phosphorus is an essential nutrient for crop growth and is routinely applied to agricultural lands; however, small amounts of phosphorus entering surface waters can cause eutrophication and harmful algal blooms. In this study, we use data collected from 24 research locations across the U.S. and Canada to better understand phosphorus inputs and outputs to diverse agricultural production systems. Phosphorus inputs (fertilizer/manre application, atmospheric deposition, phosphorus applied in irrigation water) and phosphorus outputs (crop removal, losses in runoff and tile drainage) were used to calculate phosphorus budgets for 61 production systems including cropland, forage, rangeland, and bioenergy systems. Inputs, outputs, and budgets were highly variable across the production systems. Results indicate areas where improved data collection could further our understanding of phosphorus cycling and transport. Findings also highlight important steps such as efficient use of fertilizers, adoption of P-based manure management, and consideration crop rotation for improved phosphorus management.

Technical Abstract: Phosphorus (P) budgets can be useful tools for understanding nutrient cycling and quantifying the effectiveness of nutrient management planning and policies; however, uncertainties in agricultural nutrient budgets are not often quantitatively assessed. The objective of this study was to evaluate uncertainty in P fluxes (fertilizer/manure application, atmospheric deposition, irrigation, crop removal, surface runoff, leachate) and the propagation of these uncertainties to annual P budgets. Data from 56 cropping systems in the P-FLUX database, which spans diverse rotations and landscapes across the U.S. and Canada, were evaluated. Results showed that across cropping systems, average annual P budget was 22.4 kg P ha-1 (range = -32.7 to 340.6 kg P ha-1), with an average uncertainty of 13.1 kg P ha-1 (range = 1.0 to 87.1 kg P ha-1). Fertilizer/manure application and crop removal were the largest P fluxes across cropping systems and, as a result, accounted for the largest fraction of uncertainty in annual budgets (61 and 37%, respectively). Remaining fluxes individually accounted for <2% of the budget uncertainty. Uncertainties were large enough that determining whether P was increasing, decreasing, or not changing was inconclusive in 39% of the budgets evaluated. Findings indicate that more careful and/or direct measurements of inputs, outputs, and stocks are needed. Recommendations for minimizing uncertainty in P budgets based on the results of the study were developed. Quantifying, communicating, and constraining uncertainty in budgets among production systems and multiple geographies is critical for engaging stakeholders, developing local and national strategies for P reduction, and informing policy.