我国是一个水资源较缺乏的国家.目前灌溉用水量约占全国总用水量的80%,由于工业、城镇生活用水和农业用水间的争水局面已经形成,加之水源污染日趋严重,致使灌溉用水量和用水比例逐年下降.目前在占全国总耕地面积48%的灌溉面积上,生产了占总产量2/3的粮食和农副产品,到本世纪末,为使我国粮食总产量达到5000亿公斤,还需增加灌溉面积3000万亩,即全国灌溉面积达到8亿亩.为此,需要开发新的水资源,需要发展节水灌溉.目前我国农业灌溉用水浪费十分严重,不少灌区尤其是北方灌区,自流灌区灌溉水利用系数不到0.4,井灌区一般也只有0.6左右,同发达国家相比要低 China is a country that lacks water resources.At present, the amount of irrigation water accounts for about 80% of the total water consumption in the country. As the water dispute between industrial and urban domestic and agricultural water has taken shape and water pollution has become increasingly serious, resulting in irrigation water The proportion of water and water has been declining year by year.At present, grain and agricultural by-products account for 2/3 of the total irrigated area, accounting for 48% of the country’s total cultivated area. By the end of this century, in order to make China’s total grain output reach 500 billion kilograms, But also need to increase the irrigated area of ​​30 million mu, that is, the national irrigated area reaches 800 million mu.Therefore, it is necessary to develop new water resources and need to develop water-saving irrigation.At present, the waste of agricultural irrigation water in our country is very serious, and many irrigation districts, especially the Northern Irrigation District , Gravity irrigation district irrigation water utilization coefficient of less than 0.4, well irrigation area generally only about 0.6, compared with the developed countries to be low