桂林毛村岩溶地下河流域水土流失遥感动态监测研究

RS monitoring soil erosion regime in the Maocun underground river basin,Guilin

为了给西南岩溶地区石漠化发展演变的研究工作提供一定的科学依据和决策支持,选择桂林毛村岩溶地下河流域作为研究区,利用两期遥感影像对该区影响水土流失的三个主要自然要素,即地形坡度、植被覆盖度和土地利用方式进行信息提取,并以地理信息系统为分析平台,参考水土流失强度分级标准,对该区两个时期的水土流失状况进行对比分析。调查监测结果显示,研究区随着坡度的增大,水土越容易流失,而且水土流失强度级别增大;植被覆盖度对水土流失强度起着控制性作用,为抑制并缩减水土流失面积,应保护植被,退耕还林;研究区土地利用变化比较缓慢,导致水土流失面积变化幅度不大。上述结果表明,利用遥感技术手段,可为当地的经济发展和水土流失的监测、评价、预测及治理提供参考。

In order to provide certain scientific basis and decisive support to the study of rock desertification development and evolution in southwest China karst area, this paper takes the Maoeun karst underground river basin in Guilin as the study area and uses RS image of two different periods to extract information from three main natural factors that affect soil erosion - slope gradient, vegetation coverage rate and land-use type. Furthermore, GIS is used as the analysis platform to compare the soil erosion condition in two periods in the study area ,making reference to classification standard of soil erosion intensity. The result shows that the steeper the slope the easier and more intense the soil erosion and the vegetation coverage rate also controls soil erosion intensity. In order to restrain and diminish soil erosion area, the vegetation must be protected and turn more arable land back to woods. As to the land-use type, because it changes slowly, so it doesn＇t make great effect to the soil erosion intensity. It is proved that the study on RS can provide reference for the local economic development, supervision,evaluation and forecast as well as administration of soil erosion.