Under the support of the GIS technique

the occurrence and distribution of soil erosion were studied in the plain before the mountain of the Heihe river

using the ~(137)Cs technique. And the spatial distributing rules of soil erosion under the different land use background were investigated quantificational. By the spatial analysis of the ~(137)Cs intensity

that the intensity and district difference of the soil erosion can be revealed. Furthermore

the correlation between the soil erosion and the LUCC of the region was to be discussed. Results show that it was belong to secondary erosion that in the plain before the mountain in the middle part of Heihe river

and the average soil erosion rates in the past 38 years of grassland

cultivated land and waste-land were increased in turn. Moreover

grassland cultivated in large acreage will accelerate the soil erosion. Secondly

the soil erosion capacity of the grassland

cultivated land and waste-land were about 0.4 hundred million tons

0.2 hundred million tons

1.2 hundred million tons respectively. Thirdly

the soil erosion of the region was presented increased trend in recently twenty years

the west area of it was eroded more strong

that the cosmically exploitation of the soil in the south

were made the land of current region deteriorated

therefore

the evolutive trend to the waste were accelerated in the lower reaches of the river.