Analysis Of Soil Erosion And Its Influencing Factors In Shahe River Basin Of Upper Reaches Of Wangkuai Reservoir

Soil erosion is a serious natural and ecological disaster,which affects the survival and development of human beings.Researches on soil erosion have been highly valued by scholars at home and abroad.The Shahe River Basin in the upper reaches of Wangkuai Reservoir is located in Taihang Mountains,which is prone to soil erosion.At the same time,it is one of the water sources in the upper reaches of Baiyangdian Lake.The study of soil erosion can provide scientific basis for the construction of ecological environment and soil and water conservation in the region,effectively protect the water sources in the lower reaches,provide effective guarantee for the construction and development of the downstream areas,as well as for similar areas to provide reference for the research of soil erosion.Based on this,this paper uses GIS and RS technology,taking USLE as the basic framework,extracts and produces thematic maps of soil erosion factors,completes the calculation of soil erosion modulus;validates the model calculation results with the monitoring data of many years in the study area,and studies the soil erosion situation in the study area;uses correlation analysis and ArcGIS spatial superposition analysis method.The relationships between different influence factors and soil erosion were studied,and the conclusions were as follows:(1)The degree of soil erosion in the study area is mainly slight and mild,the total area of which is 3252.49 km~2,accounting for 83.1%of the total erosion area;the average annual soil erosion modulus in the study area is about 1268.32 t/km~2·a,resulting in soil erosion of about 496.26 million t/a;the higher the degree of soil erosion is,the smaller the corresponding soil erosion area is.(2)The annual average rainfall erosivity in the study area is about 192.77MJ·mm/hm~2·h·a,with maximum value of 778.09 MJ·mm/hm~2·h·a and minimum value of 37.03 MJ·mm/hm~2·h·a.Annual rainfall erosivity has obvious correlation with annual rainfall and annual rainfall in flood season,and the correlation between rainfall and rainfall erosivity in flood season is higher.(3)The annual average sediment transport in the study area is about 224,000 tons,which varies greatly from year to year.The correlation between sediment transport and rainfall erosivity in the basin is significant.The relationship between annual sediment transport and annual rainfall erosivity is power function.(4)The areas with the most serious soil erosion in the study area are mainly located in the areas with slopes above 25°and elevations between 1200~1600 meters,and the intensity of soil erosion on sunny slopes is higher than other slopes;from the distribution law,the area of soil erosion at the three levels of light,medium and strong increases first and then decreases with the increase of the slope,which is extremely intense.The soil erosion area of the two grades increased with the increase of slope.(5)The vegetation coverage in the study area is about 45%,and high vegetation coverage can enhance soil conservation ability and prevent soil erosion effectively;the water and soil conservation ability of shrubs and grasslands are higher than that of woodlands,which can reasonably increase their area to reduce soil erosion;the soil erosion degree of unused land and bare land are relatively high,so it is suggested that these regions be reasonably developed and harnessed.