Submitted to: Environmental Modelling & Software
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/17/2010
Publication Date: 10/1/2010
Citation: White, M.J., Storm, D.E., Busteed, P.R., Smolen, M.D., Zhang, H., Fox, G.A. 2010. A quantitative phosphorus loss assessment tool for agricultural fields. Environmental Modeling & Software. 25(10):1121-1129.
Interpretive Summary: Conservation planners need a simple yet accurate tool to predict phosphorus losses from agricultural fields. Pasture Phosphorus Management (PPM) Plus is a vastly simplified interface for the Soil and Water Assessment Tool (SWAT), which predicts runoff, sediment, and phosphorus losses from fields under a variety of management scenarios and conservation practices. PPM Plus uses a modified version of SWAT which includes numerous updates, and databases supporting it’s usage throughout the state of Oklahoma. PPM Plus was developed for use in state and federally sponsored water quality improvement programs to assist in the selection of optimal conservation practices, and evaluate the resulting pollutant reductions.
Technical Abstract: Conservation and nutrient management planners need an assessment tool to accurately predict phosphorus (P) loss from agricultural lands. Available tools are either qualitative indices with limited capability to quantify offsite water quality impacts or prohibitively complex quantitative process-based models. Pasture Phosphorus Management (PPM) Plus was developed as a user-friendly P loss prediction tool based on the Soil and Water Assessment Tool (SWAT), a popular comprehensive hydrologic and water quality model. It is simple enough for use by farmers and conservation planners, applicable for both cultivated fields and pastures, and predicts P loss using a wide variety of management options and conservation practices. SWAT hydrologic components were calibrated, and databases were developed to allow application anywhere in the State of Oklahoma. PPM Plus uses a modified SWAT model that includes a number of soil P algorithm updates and improved representation of several conservation practices. This tool was successfully validated using 283 field years of measured data by White (2007). PPM Plus allows the generation of more effective conservation plans by allowing planners to evaluate P and sediment losses resulting from a particular management strategy prior to implementation.