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水是生命之源,种庄稼离不开水。我国是水资源总量较丰富的国家,常年地表水总量(2.6万亿立方米)居世界第5位;我国又是人均水资源的穷国,人均占有水量只是世界平均数的1/4。我国水资源的分布又不均匀,南方水多、人多、地少,水量有余;北方地多、人多、水少,水资源紧张。南方与北方相比,人均水量为4.4倍,亩均水量为9.1倍。在自然灾害中,旱灾对农业生产威胁最大,目前我国1/2以上的耕地没有灌溉设施,每年经常受干旱威胁的耕地有3亿亩。每年受影响的粮食达100多亿公斤。一方面水资源不足,另一方面我国水资源利用率又不高,由于田间管理、
Water is the source of life, kind of crop can not do without water. China is a country rich in total water resources. Its annual total surface water volume (2.6 trillion cubic meters) ranks the 5th in the world. China is also a poor country with per capita water resources, and its per capita water consumption is only 1/4 of the world average . The distribution of water resources in our country is uneven. There are more water in the south, more people, less land and more water. There are many places in the north, with many people, less water and less water resources. Compared with the north in the south, the per capita water volume is 4.4 times and the average water volume per mu is 9.1 times. In natural disasters, the most threatening to agricultural production is drought. Currently, more than one-half of the cultivated land in our country has no irrigation facilities. There are 300 million mu of arable land that is threatened by drought every year. Each year the affected grain reaches more than 10 billion kilograms. On the one hand, inadequate water resources, on the other hand, China’s water resource utilization is not high, due to field management,