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水,孕育和维持着地球上的全部生命。如果没有水,人类社会就无法存在。我国是严重缺水大国,水资源危机日趋加剧。它,已向中国亮出以下五个方面的“黄牌”! 一、总量大,人均少且将进一步下降 我国的水资源主要来源于降水。全国多年平均降水量640mm,全年降水总量约6×10~(12)m~3,其中44％形成径流,多年平均河川径流总量为2.7×10~(12)m~3,多年平均地下水量约
Water engenders and sustains all life on Earth. Without water, human society cannot exist. China is a major country with severe water shortages and the water crisis is increasing. It has already revealed to China the following “Yellow Cards” in five aspects: First, the total volume is large, and per capita is small and will further decline. China’s water resources mainly come from precipitation. The average annual precipitation in the country is 640mm, and the total annual precipitation is about 6×10~12m~3. 44% of the annual precipitation is runoff. The average annual total runoff of the river is 2.7×10~12m~3. The amount of groundwater is about