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榆林地区位于陕西北部,总面积44190平方公里。其中黄土覆盖面积32826平方公里,沙盖区11364平方公里。本区是黄河中游水土流失最严重的地区,平均每年通过皇甫川、窟野河、秃尾河、佳芦河、无定河等带入黄河的泥沙达5.16亿吨。在5.16亿吨泥沙中,粒径>0.025毫米的约占80%左右。这些泥沙成为黄河下游有害淤积泥沙的主要来源。
Yulin region is located in northern Shaanxi, with a total area of 44190 square kilometers. Loess which covers an area of 32,826 square kilometers, Shagai District, 11,364 square kilometers. This area is the most seriously affected area of soil erosion in the middle reaches of the Yellow River. On average, the volume of sediment brought into the Yellow River by Huangfuchuan River, Kuye River, Tuwei River, Jialu River and Wuding River reaches 516 million tons annually. In 516 million tons of sediment, particle size> 0.025 mm about 80%. These sediments have become the main source of harmful sediment in the lower Yellow River.