The President¿s Biofuel Initiative of 2006 mandates a 15% replacement of current gasoline consumption with biofuels by 2017. Critical issues surrounding this Initiative include knowing the current and future amount of available biomass feedstocks, the sustainability of producing bioenergy crops, the impact of this production on the carbon cycle, and the economics associated with adoption of bioenergy crops. An agricultural economics model, POLYSYS, has historically been funded and used by DOE to predict adoption rates of bioenergy crops, and by USDA to predict changes in land management. Incentives for adopting alternative cropping practices and bioenergy crops can have a substantial impact on carbon sources, sinks, and net carbon-equivalent emissions in the US. With previous funding from NASA, we integrated data sets and modeling components on land use, soil carbon, energy use, and greenhouse gas emissions with changes in land management predicted by POLYSYS. The newly integrated Decision Support System (DSS) is a spatially explicit framework capable of comprehensive full carbon accounting (FCA) for agricultural lands and is referred to as POLYSYS-FCA. Under this solicitation, we propose to (a) improve specific components of POLYSYS-FCA, and (b) partner with DOE and USDA to provide decision support for issues involving bioenergy crop production, carbon management, energy use, land-use change, and net carbon emissions. We specifically propose to employ a method for error propagation; integrate carbon dynamics associated with bioenergy crops; integrate an existing soil erosion model; improve on our use of NASA research results; and complete estimates of net carbon-equivalent emissions from agricultural lands in the North American Carbon Program¿s Mid-Continent Intensive region. NASA-related remote sensing products will be used in several components of the DSS.