The EPIC Model and Spatial Modeling Approaches for Modeling Carbon Dynamics, Climate Impacts, and Biofuels.

The EPIC (Erosion Productivity Impact Calculator) model is a terrestrial ecosystem model developed in the early 1980s as a tool for evaluating the status of natural resources and, specifically, for quantifying reductions in crop productivity due to soil erosion. The original model included modules for simulating weather, hydrology, erosion - sedimentation, nutrient cycling, plant growth, tillage, soil temperature, and management. Its first major application was during the 1985 Resource Conservation Act national appraisal of soil erosion impacts. Subsequently, the EPIC model has undergone many enhancements thanks to the adoption and feedback of a large, worldwide, user community. Salient enhancements have included submodels on pesticide application and fate, nitrification - volatilization, salinity, CO₂ fertilization effects on crop growth and water use, coupled C - N cycling, and denitritication. All of these capabilities have rendered an EPIC model capable of simulating a full suite of terrestrial ecosystem processes in both managed and non-managed lands for producing results relevant to science and policy applications. Recent modeling studies using EPIC have included topics such as soil carbon sequestration, net ecosystem carbon balance, climate impacts, and biofuels. High-resolution geospatial techniques and advanced computational methods have been developed to conduct regional studies on these topics. A description of the latest advancement on EPIC and examples of its application will be presented.