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一、我国水土流失概况 1.黄土高原水土流失黄土高原是我国水土流失最严重的地区,也是全世界水土流失最严重的地区,总面积约43万平方公里(共189个县旗)。其中水土流失极严重的面积为28万平方公里(共120个县旗)。每年平均向三门峡以下的黄河下游倾泻泥沙16亿吨,最多竟超过30亿吨。每年经过河口三角洲输送入海的泥沙平均约12亿吨。径流中多年
I. General Situation of Soil and Water Loss in China 1. Loess Plateau Soil and Water Loss The Loess Plateau is the most seriously affected area of soil and water loss in China. It is also the area with the most serious soil erosion in the world with a total area of about 430,000 square kilometers (a total of 189 county flags). Among them, the area with extremely serious soil and water loss is 280,000 square kilometers (a total of 120 county flags). The average annual discharge to the lower reaches of the Yellow River Sanmenxia 1.6 billion tons of sediment, up to more than 3.0 billion tons. The annual sediment transport to the sea through the estuarine delta is about 1.2 billion tons on average. Runoff in many years