气候变化领域集成服务门户

Based on the satellite image of Caohai river watershed in 2017, the land use types of Caohai river watershed were determined by field investigation, which were divided into six categories: farmland, forest land, grassland, water area, construction land and unused land. Based on SWAT model, the non-point source pollution of four regulation projects in Caohai watershed was simulated, and the runoff, sediment, nitrogen and phosphorus of non-point source pollution were analyzed in detail. The results showed that the non-point source pollution in Caohai watershed was light under the four regulation projects. The non-point source pollution is the least under the mode of conversion from farmland to forest land, grassland, water area, construction land and unused land.