陇东黄土高原土壤侵蚀变化定量遥感监测——以黄土高原水保二期世行贷款庆城项目区为例

基于SPOT和TM融合遥感影像和GIS技术,采用通用土壤流失方程RUSLE作为评价模型,计算了庆城项目区土壤侵蚀量,并结合土壤侵蚀强度分级标准,生成流域土壤侵蚀强度等级图。结果表明,项目区年平均输沙模数为7058 t/km~2,侵蚀级别属强度。研究区62．2%的泥沙来自于占流域面积仅24．8%的极强度和剧烈侵蚀区域。经分析,项目区25°以上的坡度土壤平均侵蚀量大于10168t/km~2,是水土流失治理的关键。

Quantitative Study of Soil Erosion on the Longdong Loess Plateau Using GIS and RS——A Case Study of the Qingcheng Project Area

The amount of soil erosion in the Qingcheng project area was predicted using remote sensing(RS) im- ages,Geographical information system(GIS) technology and the revised universal soil loss equation (RUSLE). The annual average amount of soil erosion in the Qingeheng project area was estimated to be about 7 058 t/km~2, belonging to intense erosion.Soil erosion degree map was obtained through soil erosion degree classification.The seriously eroded area(greater than 10 000 t/km~2) accounted for 24.8 % of the total area,but contributed 62.2 % of sediment of the whole watershed.The amount of soil loss on the land greater than 25 degree of slope was greater than 10 168 t/km~2.Therefore,control of soil loss on the land is the key to the solution of soil erosion in the area. The method of soil erosion investigation will provide quick,quantitative and scientific data for strategies of both soil erosion prevention and soil protection.