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一、总的认识黄河流域土壤的冲刷,影响了黄河的含沙量。因之促成了黄河为患的主要原因之一。所以要研究下游的水患就必须先研究黄河上中游的土壤冲刷。为了阻止这种土壤的冲刷,才举办田间土壤的保持和沟壑的治理等工作。又因为土地的不善利用,使土地变成沟壑,减少了耕作的面积,并增加了工作的困难,使表面的肥沃土壤,被雨水冲去,暴露了底土,减低了生产能力,黄河上中游的农产量因以减低。这个严重问题,早为西北的人
First, the general understanding of the Yellow River basin soil erosion, affecting the Yellow River sediment concentration. As a result of the Yellow River contributed to one of the main causes. So to study the floods downstream must first study the upper reaches of the Yellow River soil erosion. In order to prevent the erosion of this soil, soil conservation and gully management was conducted. Moreover, because of the poor use of land, the land becomes a gully, reducing the area of farming and increasing the difficulty of work, so that the fertile soil on the surface is washed away by rainwater, exposing the subsoil and reducing the production capacity. The upper and middle reaches of the Yellow River Agricultural production due to reduce. This serious problem, as early as the northwest