DRAINMOD-DSSAT Simulation of the Hydrology, Nitrogen Dynamics, and Plant Growth of a Drained Corn Field in Indiana

DRAINMOD-DSSAT is an integrated model recently developed to simulate the hydrology, water quality, and crop growth for artificially drained croplands. DRAINMOD-DSSAT is an advanced research tool that contributes to increasing productivity, reducing cost, and enhancing sustainability of crop production on high water table soils with artificial drainage. In this study, the performance of the model was evaluated using a six-year data set (1985–1990) collected from a subsurface drained agricultural research site in Indiana in the United States. Subsurface drains were installed at three different spacings (5, 10, and 20 m). During the simulation period, all treatments were planted to corn receiving high preplant N-fertilization rates. Rainfall patterns varied significantly among the years. DRAINMOD-DSSAT predictions of monthly and annual drainage flow, and nitrate losses, were in good agreement with measured values. Similarly, variations in corn yield patterns were well captured by the model across different treatments. Other crop growth-related variables and soil-N process rates were reasonably predicted compared with values reported in the literature. These results demonstrated the potential of DRAINMOD-DSSAT to simulate different components of an agricultural system involving different management practices and subjected to variable climatic conditions.