MIKE-SHE与MUSLE耦合模拟小流域侵蚀产沙空间分布特征

为有效认识流域侵蚀产沙来源，并探讨MIKE-SHE在中国黄土高原区域侵蚀产沙模拟的适用性，该研究采用分布式流域水文模型MIKE-SHE与修正的土壤侵蚀模型MUSLE耦合，对黄土高原典型小流域侵蚀产沙进行了空间分布模拟与评价。研究结果表明：流域侵蚀产沙主要来自于坡耕地和村庄、厂矿及居民用地，二者对于流域次降雨侵蚀产沙贡献平均为44%和34%。对于不同地貌单元，沟坡是流域侵蚀产沙的重要来源，其侵蚀产沙贡献高达68%。总体来看，73%的流域面积无明显侵蚀特征，而约17%为强度、极强度以及剧烈侵蚀区，剧烈侵蚀区多分布于沟坡和部分斜梁坡，这与现实流域植被覆被特征及侵蚀特征基本相符。沟道重力侵蚀是影响MIKE-SHE与MUSLE耦合模拟流域出口侵蚀产沙总量精度的重要因素之一。

Evaluation of spatial distribution of soil erosion and sediment yield for a small watershed of the Loess Plateau by coupling MIKE-SHE with MUSLE

By making use of the runoff total and two-dimension discharge to estimate the rainfall-runoff factor of R, the coupling of MIKE-SHE with MUSLE was established, and the raster-based distribution of sediment yield for a small watershed was evaluated. It was found that both sloping field and residential area accounts for 44% and 34% of the total sediment yield, respectively. While, in terms of land forms, the gully slope contributes most of the total sediment yield, with the contribution as high as 68%. In general, it was indicated that 73% of the watershed could be classified as no rill erosion, whilst around 17% of area, especially for the area of gully slope, was of severe soil erosion rate. The identified pattern of erosion rate was generally agreed with the fact that the watershed was well vegetation covered, and the erosion on the gully slope was severe. It was suggested that, to estimate the total sediment yield of the watershed by coupling MIKE-SHE with MUSLE, it is necessary to take into account the procedure of mass erosion.