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我国是世界上从事农业、兴修水利最早的国家,早在5000年前的大禹时代就有“尽力乎沟洫”、“陂障九泽、丰殖九薮”等农田水利的内容,在夏商时期就有在井田中布置沟渠,进行灌溉排水的设施,西周时在黄河中游的关中地区已经有较多的小型灌溉工程。春秋战国时期灌溉排水相有了较大发展。著名的如魏国西门豹在邺郡(现河北省临漳)修引漳十二渠灌溉农田和改良盐碱地,楚国在今安徽寿县兴建蓄水灌溉工程芍陂,秦国蜀郡守李冰主持修建都江堰使成都平原成为“沃野千里,水旱从人”的“天府之国”。但随着科技的发展以及水资源的日益紧张,现代农业和园林对节水灌溉提出越来越高的要求。目前,现有灌溉设施的灌水器大多布置在地表,一方面棵间蒸发不可避免,另一方面如果灌水器流量过大,短时间内超过田间持水量还会出现渗漏现象。因此国内外公认的理想的灌溉方式应该是由地表向地下转移,将灌水器埋在土
Our country is the earliest country engaged in agriculture and water conservation in the world. As early as 5000 years ago, the content of water conservancy in farmland such as “try our best to make dilettante”, “defeat Jiuze” and “breed” In the Xia and Shang dynasties, there were facilities for ditching and drainage in the minefield and there were more small-scale irrigation projects in the Guanzhong area in the middle reaches of the Yellow River in the Western Zhou Dynasty. During the Spring and Autumn and the Warring States period, irrigation and drainage had a great development. Well-known such as the Wei Guoxian Ximen Bao (now Linzhang, Hebei Province) Zhang Zhang irrigation drainage farmland and the improvement of saline land, Chu State in Shui County, Anhui Province to build water-saving irrigation project Shaoguan, Qin Shuguishou Li Bing presided over the construction Dujiangyan makes Chengdu Plain become “fertile land, water and drought from people ” “land of abundance ”. However, with the development of science and technology and the increasing tenseness of water resources, modern agriculture and gardens put forward higher and higher requirements on water-saving irrigation. At present, most of the existing irrigation devices are arranged on the surface of the emitter. On the one hand, it is inevitable to evaporate between the trees. On the other hand, if the flow of the emitter is too large, leakage will occur more than the field capacity in a short time. Therefore, the domestic and international recognized the ideal irrigation method should be transferred from the surface to the ground, the emitter buried in the soil