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水土流失问题是个世界性的问题,关系到一个国家的盛衰、民族的存亡。我国水土流失是全国性问题。我国丘陵、山区占总面积的2/3,水土流失现象很普遍,其中比较显著的水蚀面积150万平方公里,风蚀面积130万平方公里,二者共占国土面积的29.17％。全国丘陵、山区流失的泥沙每年约50亿吨,占世界水土流失总量的20％,每年因土壤流失的氮、磷、钾等植物营养物质,相当于全国一年的化肥生产总量。我国北方,特别是西北黄土高原,水土流失的严重性已被普遍认识;南方一
The problem of soil and water loss is a worldwide issue that concerns the rise and fall of a country and the survival of the nation. Soil and water loss in our country is a national problem. Hilly and mountainous regions in China account for 2/3 of the total area. Soil erosion is common. Among them, the water erosion area is more than 1.5 million square kilometers and the wind erosion area is 1.3 million square kilometers, accounting for 29.17% of the total land area. The annual loss of sediment in the hills and mountains in the country is about 5 billion tons, accounting for 20% of the total amount of soil and water loss in the world. Each year, due to soil erosion, plant nutrients such as nitrogen, phosphorus and potassium are equivalent to one year’s total fertilizer production in China. The severity of soil erosion has been generally recognized in northern China, especially in the Northwest Loess Plateau;