Modeling tillage and manure application on soil phosphorous loss under climate change

Abstract Phosphorus (P) losses from non-point sources into receiving water bodies play a significant role in eutrophication. Given their failure to adequately control eutrophication the Lake Erie, conservation recommendations for agricultural watersheds should be reconsidered, particularly under climate change. Using Environmental Policy Integrated Climate model, potential impacts on crop yield, surface runoff, tile drainage, and relevant dissolved reactive phosphorus (DRP) manure-amended corn-soybean rotation plots Erie basin were estimated six tillage methods with different mixing efficiencies manure broadcast application. These investigated twelve regional global future simulations. Tillage alone proved have only minor impact mean corn yield (± 2%). change led large uncertainties single treatment. As result of combined effects biogeochemical processes (e.g., supply) hydrological transport), strong negative relationships (R 2 = 0.98) found between efficiency DRP loss total loss. The application (broadcast) flow volume similar as those alone. With respect losses, labile P content outweighed runoff or drainage (hydrologic). This resulted ranging ? 60% + 151%, being closely correlated decreasing 0.94) moldboard no-till. Therefore, rotational considered reduction energy saving.