Key Factor Recognition of Non-point Source Pollution in Water Catchment Based on GIS

Catchments in main water source reservoir in Shenzhen City were analyzed based on GIS and non-point source pollution SWAT.According to the gathered special data,under the support of GIS software,the actuality of the non-point source pollution in water catchment was evaluated from the soil erosion sensitivity and spatial distribution status of "source" and "sink" landscape.Key factors of non-point source pollution in water sources of six main reservoir in Shenzhen City were obtained.And the protection measures of ecological environment in water catchment were put forward.