The Soil Erosion Distribution Characteristics and Ecological Background of Chinese Cultivated Land STUDY ON RELATIONSHIPS BETWEEN SLOPE GRADIENT AND SOIL LOSS USING ~(137)Cs TRACER Prediction of soil erosion intensity based on the land use structure—A case study from Sichuan Province Relationship between shallow landslide erosion and vegetation in the Ziwuling forest area: a case study of the “7·21” disaster in Fuxian County THE WAVELET ANALYSIS ON THE SOIL EROSION INTENSITY IN THE BLACK SOIL STRAIGHT CULTIVATED SLOPE