Policy Implications from Multi-scale Watershed Models of Biofuel Crop Adoption across the Corn Belt

The implications and value of Soil and Water Assessment Tool (SWAT)-based simulations of the productive potential and water quality impacts associated with switchgrass, Miscanthus, or corn stover removal biofuel cropping systems are discussed. Specifically, the three accompanying studies describe the water quality implications of adopting the three biofuel-cropping systems via large-scale conversion of cropland or targeting to marginal lands for three smaller watersheds located in the western or eastern Corn Belt, or across the Upper Mississippi and Ohio-Tennessee River Basins. Other results such as climate change related impacts for two eastern Corn Belt watersheds are also discussed. These studies are supported by the CenUSA Bioenergy coordinated agricultural project funded by the USDA to develop a regional system for producing cellulosic biofuels. A description of the evolving federal policy related to cellulosic biofuel production and consumption is provided as are other potential drivers for encouraging the adoption of stover removal, switchgrass, and Miscanthus as perennial feedstocks. Findings from the SWAT studies and their implications for environmental and economic performance in their respective agroecosystems are discussed, and commonalities and divergences in results are identified. The potential for policy design to improve the performance of these systems based on the findings of these modeling studies, and continuing research needs and directions for improved policy design are discussed. Editor's note: This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.