Assessment of Hydrologic System Under Projected Future Large-Scale Biomass Production and Climate Change in Upper Mississippi River Basin

Future energy and water are closely interdependent and form complex, interacting processes. To ensure energy security, significant efforts have been made to explore renewable energy sources and broaden the energy portfolio. However, the uncertainty and regional impacts on hydrologic system associated with a new mix of energy resources for various regions under climate forcings are not well understood and fully explored in a systematic manner. We examine the water resource region of Upper Mississippi River Basin (UMRB), which plays a central role of biofuel production in United States, by using a soil and water assessment tool. The study is to evaluate potential impacts on water flows, nutrient cycles, and environmental integrity under projected biofuel growth, change in land use, and global climate change. The key elements of the water components (such as evapotranspiration, soil moisture, surface runoff, groundwater recharge, etc.) and land-use changes that alter balance of water flows are investigated to identify their responses to potential biofuel production and climate change. The resultant changes in nutrient loading in river water are predicted accordingly. Some of dynamic interrelationships among water, biofuel production, crop growth and management, and climate change are quantified and demonstrated to address future sustainability. The evaluation tool developed for the UMRB water resource region provides an opportunity for further optimize management of the large-scale biomass production by taking into account spatial and temporal dynamics of the complex hydrologic system.