USING THE 137CS TECHNIQUE TO ESTIMATE WIND EROSION IN GONGHE BASIN, QINGHAI PROVINCE, CHINA

Abstract

Wind erosion is an important key to aeolian processes and land desertification in arid and semiarid areas. Accurate measurement of wind erosion rates is urgent and essential. The complexity, randomness, and boundlessness of the wind erosion process make it difficult to measure wind erosion rates precisely. Current methods have numerous limitations in their practicability, cost, and accuracy. World fallout of 137Cs from nuclear weapons tests has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. Since its first introduction in the 1960s, the 137Cs technique has been used widely in water erosion research. It was not applied to wind erosion until the 1990s and remains insufficient in this respect. Choosing the Gonghe Basin in Qinghai Province as the study area, this paper uses the 137Cs method to study wind erosion. After field surveys and 137Cs sample analysis, the characteristics of 137Cs distribution throughout the entire study area and in the soil profile are determined. The 137Cs reference inventory of the area was calculated to be 2691.78 ± 196.08 Bq m−2. Using the 137Cs model, the rate of wind erosion on the four sampling plots was estimated; then, transforming the point erosion estimates into the whole area estimates, the rate of wind erosion in the Gonghe Basin averaged 12.56 t ha−1 yr−1.