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国内外曾研究出不同类型的坡面侵蚀计算模型，但还没有一个成熟的流域侵蚀计算模型，至今流域侵蚀量仍以输沙量替代。本文充分利用黄河中游不同区域具有大量淤地坝的条件，再通过侵蚀影响因素机理的分析、在侵蚀形态类型区的划分等基础上探讨侵蚀变权模型的建设。首先选择了１５５个“闷葫芦”淤地坝，采集每个坝的年均淤积量，以及相应流域的侵蚀影响因素：植被盖度、降雨量、沟谷密度、切割深度、地表组成物质、＞１５°的坡耕地面积比等资料，采用变权形式，建立侵蚀强度宏观估算模型。最后用年降水量与年输沙量的关系对模型进行改进。得到如下适用于多沙粗沙区的侵蚀量计算模型：ｌｏｇ（Ｔｍ）＝２１．３／（３／Ｇｍ＋５５／Ｑｓｄ＋９／Ｚｘ＋１０／Ｗｘ）＋（０．９２－１．６９／（３／Ｇｍ＋７０／Ｑｓｄ＋８／Ｚｘ＋９／Ｗｘ））＊ｌｎ（Ｐｓ＊Ｐｄ）＋０．６７＊Ｒｄ－６．８５
At home and abroad have studied different types of slope erosion calculation model, but there is not a mature calculation model of the basin erosion, so far the basin erosion is still replaced by sediment discharge. This paper makes full use of the conditions of a large number of check dam in different areas of the middle reaches of the Yellow River, and then discusses the mechanism of eroded variable weight based on the analysis of the mechanism of factors affecting the erosion. First of all, 155 “silt gourd” silt dams were selected to collect the average annual siltation of each dam and the erosion factors of the corresponding basins: vegetation cover, rainfall, ditch density, cutting depth, surface composition,> 15 ° Slope area and other information, the use of variable weight form, the establishment of a macroeconomic erosion erosion model. Finally, the model is improved by the relationship between annual precipitation and annual sediment discharge. The following calculation model for the erosion rate for the coarse sediment area is obtained: log (Tm) = 21.3 / (3 / Gm + 55 / Qsd + 9 / Zx + 10 / Wx) + (0.92-1.69 / (3 / Gm + Qsd + 8 / Zx + 9 / Wx)) * ln (Ps * Pd) + 0.67 * Rd-6.85