Author
Sharpley, Andrew | |
Weld, Jennifer |
Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only Publication Acceptance Date: 7/23/2003 Publication Date: 11/4/2003 Citation: Sharpley, A.N., Weld, J.L. 2003. Using and interpreting manure phosphorus analysis for nutrient management planning [Abstract]. American Society of Agronomy Meetings. Paper No. 285030. Interpretive Summary: Technical Abstract: In response to water quality degradation associated with increased P runoff from agricultural land, EPA and USDA have implemented Comprehensive Nutrient Management Planning (CNMP) for Confined Animal Feeding Operations. The plans now require the loss of P to be addressed by three options; agronomic soil test P, environmental soil test P, and the P Index. Most states (47 of 50) have adopted the P Indexing approach in the planning process to identify areas at greatest risk for P loss and to suggest management alternatives to minimize these losses. The P Index addresses both transport (runoff, erosion and stream proximity) and source (soil test P and P applied as fertilizer or manure) factors controlling P loss. As research has shown the type of manure affects P loss, manure P solubility testing has been incorporated into the Indices to account for these variations. Due to a paucity of information on manure P solubility effects in some regions of the U.S., several states use book values, while others have developed simple tests that yield inputs to Indices. We will discuss how states are using this information in CNMP's and suggest ways in which more widespread adoption of these techniques may give a more reliable risk assessment of P loss. |