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1973年世界性石油危机唤起了人们对节能的重视,而出现了许多新的灌水方法,1982年才崭露头角的拖管灌溉法就是其中一种。拖管灌溉法(frailfuhe irrigafion)也可简称为拖灌,是用打有孔的聚乙烯软管来代替通常的喷头,连接在时针式喷灌机或平移式喷灌机的移动支管上,软管从支管上悬挂下来,大部分长度拖在地下,当支管向前行走时就拖着这些软管向前移动,水在较低的压力(约150
The worldwide oil crisis in 1973 aroused people’s attention on energy conservation, and many new irrigation methods emerged. One of them was the draft pipe-pulling irrigation law that emerged in 1982. The frailfuhe irrigafion, also referred to as drafting, is a perforated polyethylene hose instead of a normal sprinkler attached to a moving branch of an hourglass or pan-type sprinkler. The hose from The branch pipe is suspended and most of the length is dragged underground. When the branch pipe is moved forward, the hose is dragged forward and the water is moved at a lower pressure (about 150