在我国北方五十年代开始的修水库或自流引水灌溉为农田灌溉的第一次进展;六十年代后期的大规模机井建设为第二次进展。而现在面临着的第三次进展是以管道输水——“管灌”为标志。全面节水是缓解北方水资源供需矛盾最基础的一环,是北 The first progress of irrigation in reservoirs or gravity irrigation started in the 1950s in the northern part of our country. The second large-scale construction of the well in the late sixties was the second progress. The third progress now facing is based on pipeline water transport - “pipe irrigation” as a symbol. Comprehensive water-saving is to alleviate the contradiction between supply and demand of water resources in northern China is the most basic part of the North