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沟蚀是土壤侵蚀研究的主要内容之一,地形地貌是沟蚀的一个重要影响因子。本文以安塞纸坊沟流域作为研究区域,选择土地利用方式、土壤类型、坡度坡长因子、平面曲率、坡向和地形湿度指数6个因子,通过因子内切沟所占比重/整个研究区切沟所占比重计算各个因子的权重值,通过空间叠加分析土壤侵蚀敏感性,并通过重分类的方法把土壤侵蚀敏感性分为基本无侵蚀、轻度侵蚀、中度侵蚀、强度侵蚀、剧烈侵蚀5个等级,来研究切沟侵蚀与地形的关系。结果表明:切沟多发生在坡度坡长较大、地表湿度较高的林草地区域和更容易发生侵蚀的黄绵土区域,并且多分布在阴坡的凹面;对比分析切沟侵蚀和土壤侵蚀敏感性,切沟大多分布在中等侵蚀敏感性以上的区域,约占总切沟的90%;实验权重值对验证区冲沟的响应精度为82.43%(中度侵蚀及其以后阶段),与实际值90.53%相差不大,说明此种方法对黄土丘陵沟壑区具有一定适用性,对黄土丘陵沟壑区水土保持工作有重要意义。
Gully erosion is one of the main contents of soil erosion research. Topography is an important factor affecting gully erosion. In this paper, we take the Ansai-Zhifanggou Basin as the research area and choose six factors of land use pattern, soil type, slope slope length factor, plane curvature, aspect and topography humidity index, According to the proportion of ditches, the weight value of each factor is calculated, the sensitivity of soil erosion is analyzed by spatial superposition, and the sensitivity of soil erosion is divided into basic non-erosion, mild erosion, moderate erosion, intensive erosion and severe erosion 5 levels, to study the relationship between erosion and topography. The results show that the cutting ditches occur mostly in the grassland areas with steep slopes and high surface humidity and the loess areas prone to erosion, and are mostly distributed in the concave surface of the shady slopes. The sensitivity of the gully erosion and soil erosion is comparatively analyzed , And most of the ditches are distributed in the area above the medium erosion sensitivity, accounting for about 90% of the total ditch. The response accuracy of the experimental weight to the gully in the verification area is 82.43% (moderate erosion and later stages) 90.53%, showing that this method has certain applicability to the gully region of the Loess Plateau and is of great significance to soil and water conservation in the hilly and gully regions of the Loess Plateau.