Jianghuai watershed area is located in the transition zone between warm temperate zone and subtropical zone, with an average annual precipitation of 900 ~ 1000 mm and relatively abundant rainfall. Affected by the frequent intersection of cold and warm air, the temporal and spatial distribution of precipitation is uneven, with great intra-annual and inter-annual changes; Groundwater is deeply buried and has few reserves. It is only used as drinking water source for people and animals in some areas. The terrain in the area extends along the eastern foot of Dabie Mountain, with high in the west and low in the east, undulating hills, criss-crossing hills and gullies and broken terrain. Although the total amount of precipitation along the line and on both sides of the watershed ridge is abundant, it is difficult to store and use it in large quantities, and it is difficult to lose more by stagnation.