三峡库区土壤侵蚀遥感定量监测——基于GIS和修正通用土壤流失方程的研究

Remote sensing quantitative monitoring of soil erosion in Three Gorges Reservoir area:a GIS/RUSLE-based research

在GIS技术的支持下,通过遥感技术和野外调查进行信息采集,选用修正的通用土壤流失方程(RUSLE)估算了整个三峡库区的年均土壤侵蚀量,分析了土壤侵蚀的空间分布特征,计算了不同土地利用类型的土壤保持能力,并对库区进行了防治强度预报。结果表明,三峡库区年均土壤侵蚀量为18476.27×104t/a,平均土壤侵蚀模数为3316.53 t/(km2.a),属于中度侵蚀。库区年均土壤保持量为48427633×104t/a,其中有林地、其他林地和高中覆盖度草地的年均土壤保持量最大,水田保持土壤能力最强,旱地保持土壤能力最小。库区预防强度预报结果为2005年三峡库区需要治理和急需治理的面积占总面积的25.67%,所占比例较大,预防和治理土壤侵蚀的任务比较艰巨。

Based on geographic information system（ GIS）, remote sensing（ RS）, field information gathering and revised universal soil loss equation（RUSLE） ,the mean annual soil erosion amount in whole Three Gorges Reservoir area was estimated, the spatial distribution characteristics of soil erosion was analyzed, the soil conservation capacity of diffevent land use types was calculated and the soil erosion prevention and control forecast was carried out for the reservoir area. The results show that the mean soil erosion amount and the soil erosion modulus were 18476.27×10^4t/a and 3316.53 t/（km^2·a）, respectively. The annual soil conservation amount was 48427633×10^4t/a. Among the land use types, the soil conservation capacity of paddy field is the strongest, and that of dry land is the smallest. The area to be controlled and controlled rapidly in 2005 occupied 25.67% of the Three Gorges Reservoir area. The integrated approach presented in this study allows relatively easy, fast and cost- effective estimation of spatially distributed soil erosion. It thus orovides a useful and efficient tool for predicting long-term soil erosion potential and assessing erosion impacts on soil conservation practice.