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一、前言近几年来,低压管道输水灌溉系统在我国北方灌区得到很大发展。目前,全国管灌面积已达3000多万亩,其中绝大部分面积分布在山东、河北、河南、北京和天津。西北五省(区)管灌工作起步较晚,除甘肃省现有管灌面积5万多亩外,其余各省(区)只有零星试点。山东省管灌发展最为突出,1988年达到1288万亩,年增产粮食10亿公斤,节省地19.3万亩,节水10亿立方以上,经济效益显著。由于管道输水灌溉,减少了田间渗漏,生态效益也很明
I. Introduction In recent years, low-pressure pipelines have received great development in irrigation systems in northern China. At present, the area of pipe irrigation in China has reached more than 3,000 mu, of which the vast majority are in Shandong, Hebei, Henan, Beijing and Tianjin. The management of irrigation and irrigation in the five provinces (autonomous regions) in the northwest started relatively late. Except for the existing irrigation and irrigation area of Gansu Province of more than 50,000 mu, the rest of the provinces (autonomous regions) only carried out sporadic experiments. Shandong Province, the most prominent irrigation and pipe irrigation in 1988 reached 12.88 million mu, the annual increase of 1 billion kg of grain, saving 19.3 million mu, saving more than 1 billion cubic meters, significant economic benefits. As the pipeline irrigation, reducing field leakage, ecological benefits are also clear