三峡库区腹地土壤侵蚀动态演变研究

以三峡库区腹地5个区县为研究区，以1988、2000、2010和2015年4期遥感数据为数据源，借助RS和GIS技术，得到研究区土壤侵蚀数据，采用土壤侵蚀综合指数，从区域尺度、乡镇尺度分析三峡库区腹地土壤侵蚀时空演变规律及其差异性。结果表明：（1）在27a间，区域尺度的土壤侵蚀状况呈现波动性演变，2000年以前研究区土壤侵蚀状况在恶化，而2000年以后侵蚀状况逐渐好转并趋于稳定;（2）在乡镇尺度上，进一步分异，出现4种演变类型：持续性变好、持续性变差、波动性变好、波动性变差；主体演变类型与整体大体一致，但在云阳县和长江沿岸存在与整体相反的演变类型；（3）侵蚀状况始终严重或持续性变差的12个乡镇为治理重点区域，而波动性变差的24个乡镇为治理的次重点区域。研究结果有助于该区域水土流失的精准治理。 关键词： 土壤侵蚀演变；土壤侵蚀综合指数；多尺度研究；三峡库区腹地

Temporal-Changes in Hinterland Soil Erosions Within Three Gorges Reservoir Area

This study includes five county-based hinterland locations located within Three Gorges Reservoir Area (TGRA).Based on the Remote Sensing Imagines in the years of 1988,2000,2010 and 2015,the GIS and RS techniques were applied for data extraction of the soil erosion integrated index to analyze temporal variations of hinterland soil erosion at the regional and local scales within the TGRA.The two results were found as follows:(1) at the regional scale (i.e.Entire study area),the hinterland soil erosion fluctuated dramatically to be worsened until the year of 2000,and then improved gradually to be in stable;(2) at the local scale,the hinterland soil erosion evolved in temporal trend with four different types (i.e.Continuously-improved,Continuously-worsen,Fluctuating-improved,and Fluctuating-worsen).Temporal trend of soil erosion was found with the same type among most of local areas in this study,except for the Yunyang County and areas which are located nearly by the reservoir;(3) the priority of governance and management should be emphasized on the 12 towns which were identified as the continuously-worsen type,and followed by other 24 towns which were classified as the fluctuating-worsen type.All aspects of the study findings will have important implications specified to the governance and management of TGRA.