联结在移动式灌溉机械(见图)上的多孔的聚乙烯软拖管已设计出,以代替灌溉喷头,其孔距、孔径是根据与土壤吸水速率相对应的供水率来确定的,因而,地表径流得到了控制。管内工作压力为10～50kPa,这意谓着需要很低的能量。管中绝大部分水施于作物顶盖以下,这样,由于蒸发和风速引起的水量损失减少到了最小程度。 A porous polyethylene flexible pipe connected to a mobile irrigation machine (see picture) has been designed to replace the irrigation sprinkler and its hole pitch and aperture are determined on the basis of the water supply rate corresponding to the soil water absorption rate. Therefore, Surface runoff has been brought under control. Working pressure within the tube is 10 ~ 50kPa, which means that low energy is needed. Most of the water in the pipe is applied below the roof of the crop so that the loss of water due to evaporation and wind speed is reduced to a minimum.