Spatial distribution and estimation of soil erosion in the gonghe basin of qinghai-tibetan plateau (China)

In the study, we traced the ¹³⁷Cs isotopes in many soil samples from the Gonghe Basin, and combined the results with TM remote sensing data, geological data, topographic data and other multi-source information synthesis. We then took the ¹³⁷Cs massic activity and area activity in the soil as the major data, formed the area activity distribution diagram by means of interpolation, made use of the vegetation coverage map (NDVI value), land use and cover maps, and surface composition map, and conducted spatial overlay operation of four layers to obtain the spatial distribution diagram of soil erosion of the Gonghe Basin. Most areas of the Gonghe Basin were involved in micro and slight erosion, accounting for 57.0% of the total area of the Gonghe Basin, the area with moderate erosion accounted for 31.1% of the total area, the area with severe erosion accounted for, and the water area accounted for 2.5%. The central part of the basin was involved in the most severe erosion, the degree of erosion successively decreased toward the outside and reached the minimum in the surrounding mountainous region, and the part with relatively severe soil erosion occurred on the both sides of the Shazhuyu River as the axis, and extended in the northwest-southeast direction toward Taaras Beach and Muge Beach. As seen from the above, the soil erosion of Gonghe Basin has a relatively high potential risk and the land with moderate erosion accounted for 1/3 of the total basin area, therefore it is further required to strengthen environmental construction and protection, increase the scale and degree of vegetation coverage, reduce original surface vegetation deterioration and soil loss, and protect sand vegetation, especially fragile vegetation such as sand bush and halophyte bush. We must restrain the rapid extension of the soil area with moderate erosion, continually protect micro and slight soil erosion area, and prevent the Gonghe Basin from accumulating large areas of severe and high soil erosion.