Surveying soil erosion condition in Loess Plateau using soil erosion model

Soil erosion survey is important for land resources protection and natural disasters prevention. A new soil erosion survey method was proposed and Wuqi county in Shaanxi province was taken as a research object. 39 units were sampled by 1% uniform sampling ratio. Chinese soil loss equation (CSLE) was used to calculate soil loss, which was compared with soil loss estimated by “standards for classification and gradation of soil erosion”. Average soil erosion modulus by two methods was 4 571 t/(km2×a) and 5 504 t/(km2×a) respectively, but the area and spatial distribution of soil loss in each grade were obviously different between them. More information was obtained on land use/land cover, soil conservation practices and soil properties by uniform sampling survey than that obtained by remote sensing and the information was properly representative of the whole survey region. Compared to “Standards for Classification and Gradation of Soil Erosion”, soil erosion effecting factors include else factors such as soil erodibility, slope length and soil conservation practices were considered in CSLE. Therefore, survey results based on sampling and soil loss prediction model are more reliable than those based on remote sensing and “standards for classification and gradation of soil erosion”.