基于水土流失风险的流域景观格局识别方法研究

运用"源、汇"景观理论,利用洛伦兹曲线,考虑了植被覆盖因素,基于景观坡度指数,构建了景观空间负荷对比指数,定量分析了丹江流域9个子流域的景观空间格局。结果表明:丹江流域北部各子流域主要以水土流失的"源"景观为主,景观坡度指数大,空间负荷指数小,水土流失风险大;流域南部各子流域上游以"汇"景观为主,坡度指数大,中下游以"源"景观为主,景观空间分布不均衡,存在一定的水土流失风险。

Method of Watershed Landscape Pattern Analysis Based on the Risk of Soil and Water Loss

Based on Source-sink principle and Lorentzian curve,this paper analyzed the landscape pattern of nine watersheds in Danjiang River Basin and constructed landscape slope index and location-weighted landscape contrast index.The results showed that the landscape in the watersheds of the northern basin was dominated by soil water loss ’source’ landscape with bigger landscape slope index and smaller location-weighted landscape contrast index.The risk of soil water loss in those watersheds was very high.The landscape of the upper watersheds in the southern basin was dominated by ’sink’ landscape with bigger landscape slope index,while ’source’ landscape was dominated in the down reach.The distributions of ’source’ and ’sink’ landscapes were uneven in the watersheds,which made a higher risk of soil water loss.