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Soil crosion in karst region of south China is one of the major environmental problems, beryllium-7, produced by energetic cosmic rays, has been used to trace the geochemical process of the soil erosion. The study has shown that 7Be activity profiles present a decreasing logarithmic pattern with soil depth. The maximum permeable depth of 7Be is 2 5mm in different seasons and locations, which is deeper in autumn than in spring. On the contrary, its apparent activity on boundary soil is higher in spring than in autumn The 7Be inventories in soil cores are higher in accumulative locations than in eroded one Upper hills in the karsl region are seriously eroded, Erosive intensity is higher in rainy periods than in dry ones Influenced by the micromorphology and precipitation, the eroded particles accumulated in shallow basin after a short-distance transportation in winter and spring However, in summer and autumn, they might be transported into drainage systems
The study has shown that 7Be activity profiles present a decreasing logarithmic pattern with soil depth. The maximum permeable depth of 7Be is 2 5mm in different seasons and locations, which is deeper in autumn than in spring. On the contrary, its apparent activity on boundary soil is higher in spring than in autumn The 7Be inventories in soil cores are higher in accumulative locations than in eroded one Upper hills in the karsl region are seriously eroded, Erosive intensity is higher in rainy periods than in dry ones Influenced by the micromorphology and precipitation, the eroded particles accumulated in shallow basin after a short -distance transportation in winter and spring However, in summer and autumn, they might be driven into drainage systems