Modeling the impacts of sugarbeet for biofuel production on soil and water quality using the Root Zone Water Quality Model (RZWQM)

Abstract. Sugarbeets are being considered as one of the most viable feedstock alternatives to corn for biofuel production since herbicide resistant energy beets were deregulated by USDA in 2012. Growing sugarbeets for biofuel production may have significant impacts on soil health and water quality in the north-central regions of the US where 50% of the nation‘s total sugarbeets were produced in 2015. Little or no research has been done to study the water quality impact of growing sugarbeets for biofuel production. The Root Zone Water Quality Model (RZWQM) is a widely used model that can simulate crop yield, water flow, and transport of salts and nitrogen in crop fields. RZWQM is linked to 23 specific crop models in the Decision Support System for Agrotechnology Transfer (DSSAT), not including a sugarbeet model. In this research, Crop and Environment REsource Synthesis (CERES) Beet model was incorporated into DSSAT, which was in turn linked with RZWQM to model the soil and water quality impact of growing sugarbeet for biofuel production. The RZWQM was then tested against field data collected at the Carrington Research and Extension Center (North Dakota) in 2014 and 2015. PEST (Parameter Estimation) was used for sensitivity analysis and parameter estimation.