基于遥感和GIS的桑干河流域土壤侵蚀评价

Using Remote Sense and GIS Techniques to Assess Soil Erosion in Sanggan River Watershed

以桑干河流域Landsat 5 TM和DEM为数据源,依据水利部颁布的《土壤侵蚀分类分级标准》(SL 190-96),采用第二次全国土壤侵蚀遥感调查中的多因素综合法,选取土地利用类型、植被覆盖度和坡度3个因子,对桑干河流域土壤侵蚀强度进行了评价,发现桑干河流域平均侵蚀模数约为1655t/km2.a,总体上属轻度侵蚀,但侵蚀强度较高的斑块破碎化程度高,不利于集中治理,土壤侵蚀的防治有一定难度。

Soil erosion of Sanggan River watershed was assessed using RS and GIS techniques. Soil Erosion Classification Grade Criteria （SL 190-96） issued by the Ministry of Water Resources, Landsat TM images acquired in 2007, and DEM data acquired in 2001 were employed in the study. The multifactor compre- hensive method in the second national soil erosion investigation was adopted, and three factors of land use class, vegetation coverage and slope were selected as assessing indices. It is found that the average erosion modulus is about 1 655 t/kin2 a, representing a low-grade of soil erosion in Sanggan River watershed. However, soil and water conservation in this region might be difficult because the areas with intense soil erosion are usually fragmentized and not suitable to be managed uniformly.