The Simulation Research on Non-Point Source Pollution in Lianshui Watershed

Non-point source pollution (NPSP) is an important factor that affects water quality. To study the effect of the pollution on water quality, the Soil and Water Assessment Tool (SWAT) is applied to simulate runoff and nutrient concentrations in the Lianshui Watershed. In the monthly time step, the model’s Nash-Sutcliffe coefficient and the coefficient of determination indicated that the values of simulated runoff, nutrient concentrations are acceptably closer to the measured data. Then, the study concluded that NPSP is the dominant factor affecting the water quality of the Lianshui River. Finally, the study also explored the temporal and spatial distribution characteristics of NPSP in the watershed.