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水土流失是我国一大环境问题。我国是世界上水土流失最为严重的国家之一,全国水土流失面积达4.92×10~6km~2,占国土面积的51%(见表1),其中水蚀面积1.79×10~6km~2,占国土面积的1/6左右。全国每年流失的土壤达5×10~9t。
Soil and water loss is a major environmental issue in our country. China is one of the countries with the most serious soil erosion in the world. The area of soil erosion in China reaches 4.92 × 10 ~ 6km ~ 2, accounting for 51% of the total land area (Table 1). The water erosion area is 1.79 × 10 ~ 6km ~ 2 About 1/6 of the land area. The country lost soil each year up to 5 × 10 ~ 9t.