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过去关于水土保持措施影响的研究多侧重于减水减沙的影响，对泥沙组成影响的研究则相对较少。本文以大量的实测资料为依据，以河口至龙门间区域自然与水土保持条件为背景，将水保措施类型、河道水流泥沙条件与流域地貌条件结合考虑，借助统计分析方法对采用水保措施前后该区域（尤其是与黄河中游水土流失密切相关的黄土高原与沙砾丘陵区域）的泥沙粒径分布变化进行了探讨。分析表明，泥沙粒径分布变化极其复杂，对应于不同地貌类型条件的泥沙组成遵循不同的分布规律。黄土丘陵区河流中的悬移质泥沙级配服从正态分布规律，而沙砾丘陵区河流中的泥沙级配则服从皮Ⅲ型分布规律。当分布函数的类型确定后，泥沙粒径分布由该分布函数的几个参数共同决定，这些参数分别反映了泥沙从流域表层搬运到对应级别河流的过程中地貌形态及水土保持措施的影响。文中由多学科综合研究得到的结论，对黄河中游水土保持效益研究具有重要意义。
In the past, studies on the impacts of soil and water conservation measures focused on the impact of water and sediment reduction, while relatively few studies on the impact of sediment composition. In this paper, based on a large number of measured data, taking the natural and soil and water conservation conditions as the background between estuary and gantry, taking the types of water and soil conservation measures, the conditions of river flow and sediment and the basin topography into account, The changes of sediment particle size distribution in the area around the Yellow River, especially in the loess plateau and gravel hilly area, which are closely related to soil erosion in the middle reaches of the Yellow River, are discussed. The analysis shows that the distribution of sediment particle size is extremely complicated. The sediment composition corresponding to different types of landforms follows different distribution rules. The suspended sediment distribution in rivers in the Loess Hilly region obeys the normal distribution, whereas the sediment distribution in the gravel hilly region obeys the distribution of skin type Ⅲ. When the type of distribution function is determined, the distribution of sediment particle size is determined by several parameters of the distribution function, which respectively reflect the influence of topography and soil and water conservation measures during sediment transport from the surface to the corresponding river . The conclusion drawn from multidisciplinary comprehensive study in this paper is of great significance for the study of benefits of soil and water conservation in the middle reaches of the Yellow River.