Impacts of biofuel-based land-use change on water quality and sustainability in a Kansas watershed
Published in Agricultural Water Management, 2016
Recommended citation: Yasarer L.W., S. Sinnathamby, B. Sturm. (2016). "Impacts of biofuel-based land-use change on water quality and sustainability in a Kansas watershed." Agricultural Water Management. 175(2016). https://www.sciencedirect.com/science/article/pii/S0378377416301585
Abstract: The growth in ethanol production in the United States has sparked interest in potential land-use changeand the associated environmental impacts that may occur in order to accommodate the increasingdemand for grain feedstocks. In this study water quality and sustainability indicators are used to eval-uate the impacts of land-use change to increase corn and grain sorghum acreage for biofuel productionin the Perry Lake watershed in northeast Kansas. Water quality indicators include sediment loads perconverted land acreage and the relative increase of total nitrogen, total phosphorus and sediment loadscompared to the baseline conditions. Sustainability indicators include land-use, water use, and nutrientuse efficiencies. Hay, Conservation Reserve Program (CRP), and winter wheat were selected as targetedland-uses for conversion to biofuel feedstocks. The Soil and Water Assessment Tool (SWAT) was usedto evaluate 6 different scenarios, each at 10 land-use change increments, for a total of 60 simulations.Results demonstrate that increased corn production generates significantly greater sediment loads thanincreased grain sorghum production and larger relative increases in nutrient loads. Expansion of cornor grain sorghum cropland by replacing hay or CRP land-uses resulted in the highest sediment loadsand relative increases in nutrient loads. Expansion of corn or grain sorghum by replacing winter wheatcropland produced the lowest relative changes in nutrient and sediment loads and therefore may be amore sustainable land-use change. Corn had a higher yield potential per km2compared to grain sorghum,resulting in better land, nutrient and water use efficiencies.