Watershed-Scale Impact of Land-use changes for Bioenergy Production

摘要

USDA goals for meeting renewable fuels standards by 2022 indicate that 50% of the advanced biofuels to be produced in the U.S. are expected to come from the Southeastern U.S. High net primary productivity of the region from a favorable climate and productive soils make these goals attainable. Meeting these goals will require conversion of row-crops to high-yielding biomass crops. Changes in water resources, both quantity and quality, are anticipated with these changes. Biomass crops provide excellentground cover, are believed to have lower water use requirements, and have high nitrogen use efficiency. The Soil and Water Assessment Tool (SWAT) was used to examine the long-term impacts of land-cover changes associated with bioenergy production. Simulations indicate conversion of existing production land into grass and forest bioenergy crops will result in: 1) decreased evapotranspiration; 2) increased streamflow; 3) decreased sediment loading; and 4) seasonal shifts in streamflow.