共和盆地塔拉滩土壤侵蚀潜在危险度的分级研究

Gradation of potential soil erosion danger in Tala Shoal of Gong-he Basin

在ARCGIS 9.3地理信息系统支持下,实现了土壤侵蚀潜在危险度的分级及其空间分析。以青藏高原东北部的共和盆地塔拉滩草原为研究对象,首先采用地球化学放射性同位素-137Cs侵蚀模型估算土壤侵蚀量,再由土壤年均侵蚀量、土层厚度和土壤容重得到抗蚀年限图。参照水利部标准将土壤侵蚀潜在危险度分为5级,同时分析了不同坡度和不同土地利用类型上的土壤侵蚀潜在危险度。研究表明:共和盆地塔拉滩的土壤侵蚀潜在危险度以轻险型为主,从土壤侵蚀潜在危险指数(SEPDI)来看,属于轻度危险区域。

In this paper,tracer technique of geochemical radioisotopes-137Cs was used to estimate the soil erosion in tala shoal grassland of Gong-he Basin northeastern Tibetan Plateau;Field investigation and soil survey were adopted to establish the soil bulk density and soil thickness figure.According to the average annual amount of soil erosion,soil bulk density and soil thickness,we got the useful life figure of anti-erosion based on ARCGIS 9.3.And then the degrees of potential danger of soil erosion have been graded with the characteristics of soil erosion and referring water conservancy department standard.The results showed that in this region,mild type of soil erosion dominates the main area is 1692.98km2,accounting for 61.64% of the total area.