The Alpine Meadow Soil Erosion And The Space Distribution Features In Xinghai Basin

Soil erosion was an environmental issue that been people high attention in the world. The soil erosion has brought serious impact to ecology and human sustainable development. Xinghai basin is located in high altitude areas, its ecological environment status significantly vulnerable and the position significantly, with the freeze-thaw erosion, water erosion and wind erosion. Xinghai basin are mainly composed of alpine meadow, but if alpine meadow is damaged by natural disasters or humans, it is hard to recovery immediately, and we must protection the alpine meadow. Because of the warm global climate and the unreasonable development of humans,the destruction process of alpine meadow speed up and the soil erosion will also increase.It is convince and fast to using nuclide ¹³⁷Cs tracer technology to reflect the strength of soil erosion and the erosion rate, Quantitative analysis of the typical erosion resistance of alpine meadow.We get the green south plateau Xinghai basin Zi ke-tan as the study area, Using the nuclide ¹³⁷Cs tracer technology principle, We collected total of 72 sample, 39 soil profile samples, 32 density samples. Test samples using gamma spectrometer. Its relative detection efficiency is 50.2%, A single sample test time of 43200 s, Test error control within 10% as far as possible, Samples of ¹³⁷Cs activity value in the study area are obtained.The areas is located in high altitude, temperature change obvious and the rainfall is large, temperature changes usually, Temperature, daily range of 12 ℃-16 ℃, In less than 25 ℃, 34 ℃. The areas mainly composed of alpine meadow, The roots to soil particles caking and conservation of water higher, Meadow thick skin can reduce the erosion of the surface soil by the heavy rain, and the soil erosion is smaller. T Research area as the typical non-agricultural of cultivated land, ¹³⁷Cs activity with depth exponentially decreasing trend, Combining with the exponential equation, Research area of nuclide ¹³⁷Cs exponentially reducing distribution in alpine meadow soil layer, ¹³⁷Cs activity peak appeared in the surface layer 1-2 cm, the following 5-6cm almost no ¹³⁷Cs distribution, Soil erosion change range of 151.39t·km-2·a-1 to 359.10 t·km-2·a-1, with an average of 317.08 t·km-2·a-1. In soil bulk density between 0.939 g·cm-3 to 1.309 g·cm-3, with an average of 1.140 g·cm-3. Erosion rate changes ranging from 0.16 mm to 0.33 mm a year, the mean value of 0.28mm·a-1. Accumulation rate varied from 0.26 mm·a-1 to 0.77 mm·a-1, Accumulation amount range from 291.03t·km-2·a-1 to 801.33 t·km-2·a-1.By the space, The occurrence of the largest erosion is the regional Xinghai County surrounding area, And the amount of erosion from the edge of the study area to Xinghai County gradually increased, Zi ke-tan eastern erosion is more serious than the western region, erosion size from the edge of the study area showing an increasing trend tward the center of Xinghai country area. Zi ke-tan vegetation cover eastern region lower than the western region, soil erosion is lighter. Vegetation cover and soil erosion distribution of the same trend in the space.