Assessing the impacts of crop-rotation and tillage on crop yields and sediment yield using a modeling approach

a b s t r a c t This study was conducted in the Big Sunflower River Watershed (BSRW), north-west, Mississippi. The watershed has been identified as "impaired waters" under Section 303(d) of the Federal Clean Water Act due to high levels of sediment and total phosphorus. This excess is then transported to the Gulf of Mexico via the Yazoo River, further damaging the nation's water resources. The specific objectives of this study were to assess the impact of corn (Zea mays L.), soybean (Glycine max (L.) Merr., and rice (Oryza sativa, L.) crop-rotations (corn after soybean, soybean after rice, continuous soybean) and tillage practices (conventional, conservation, no-till) on crop yields and sediment yield using the Soil and Water Assessment Tool (SWAT) model.