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1 地面灌溉技术概述地面灌溉是世袭的古老灌溉技术。就世界范围看 ,无论在什么情况下 ,地面灌溉都占灌溉面积的绝对优势。全世界地面灌溉的面积约占世界灌溉总面积的 90 % ;我国现有地面灌溉面积约 0 .467亿ｈｍ2 (2 0 0 0年 ) ,占全国总灌溉面积 0 5 47亿ｈｍ2的 85 %以上 ,
An overview of surface irrigation technology Surface irrigation is a hereditary ancient irrigation technology. As far as the world is concerned, surface irrigation accounts for the absolute advantage of irrigated area no matter under what circumstances. The area of surface irrigation around the world accounts for about 90% of the total irrigated area in the world. In China, the existing surface irrigation area is 0.4667 billion hm2 (2000), accounting for more than 85% of the country’s total irrigation area of 57.7 billion hm2 ,