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我国位于大陆性季风气候地带,旱灾频繁,降水分布不均,灌溉在农业生产中作用巨大。全国灌溉农田面积5466.7万hm2,占耕地总面积的43%,其余57%为雨养农田。正常年份农业缺水300多亿m3,约667万hm2灌溉农田得不到灌溉保障。近10年来,每年旱灾面积约2466.7万hm2,减产粮食约300亿kg,水
China is located in the continental monsoon climate zone with frequent droughts and uneven distribution of precipitation. Irrigation plays a significant role in agricultural production. The area of irrigated farmland in the whole country is 54.667 million ha, accounting for 43% of the total cultivated land area and the remaining 57% are rainfed farmland. In normal years, there are over 30 billion m3 of agricultural water shortages and about 6.67 million hm2 of irrigated farmland are not protected by irrigation. In the past 10 years, the annual drought area has reached 24,667,000 hm2, and the output of grain has reduced by 30 billion kg. The water