Assessing the Impact of Land Management Practices On Watershed Runoff Using MIKE SHE.

Agricultural runoff and associated non-point source pollutants have led to extensive impairment of water bodies in the U.S. Corn Belt region. Land management practices have demonstrated the potential for improving water quality in rowcrop agricultural system. To enhance our understanding of the hydrologic footprint of land management practices, a coupled MIKE SHE/MIKE 11 model was used to simulate the major hydrological processes in a 5000-ha agricultural watershed in central Iowa. Monitored 5-year daily flow was used to calibrate and validate the model. The results showed that the model had a good performance simulating flow discharge from late spring to fall but underestimated the flow in winter and early spring. The impact of land use change in the study watershed on flow discharge was then assessed using the MIKE SHE model.