我国北方地区合理开发水源发展灌溉的基本途径

我国北方地区主要跨越了干旱、半干旱、半湿润三个自然地理带。它包括了黄淮海平原、松辽平原、天山南北山前平原、河西走廊以及黄河谷地、山间盆地等主要农业区。干旱,是这些地区发展农业生产最普遍的矛盾,同时又伴随着土壤盐碱化,在不少地区还有“内涝”和水土流失、泥沙淤积危害。本文主要以开发水源发展灌溉与改善生态环境——旱、涝、土壤盐碱化治理与减轻泥沙淤积等相协调的观点,分析了我国北方地区合理开发水源发展灌溉的基本途径和形式,提出一得之见,以供讨论。

BASIC WAYS OF RATIONAL EXPLOITATION AND IRRIGATION OF WATER RESOURCES IN THE NORTHERN AREA OF CHINA

In the northern area of China according to the ecological environment and the elementary characteristics of water resources and dynamics of water and salinity, and from the viewpoint of coordinating the exploiting water resources for developing irrigation with improving ecological environment, some expositions are given in this paper as follows.(1) The exploitation of water resources at most irrigation districts of the northern China plain must combine the surface water with groundwater as a whole in comprehensive utilization Above all, the shallow groundwater ought to be exploited enthusiastically. The surface water can only be channelled properly under the condition of the demands of reasonable regulation of the shallow groundwater.(2) A project of water and soil conservantion of the constrvction of reservoirs, water can be clear and sand can be drained are necessary to put into practice at hilly and mountain districts. and the stor age of loodwater at plain districts, lo channel muddy floodwater into the warping field and develop well irrigation of floodwater techarge are basic ways of harnessing a muddy and sandy river and regulating 'he runoff storage. From all of these measures, devoting major efforts to developing well irrigation of floodwater recharge is a key link in changing bane into boon and using the floodwater and sand resources fully.(3) Provided that shallow groundwater is exploited positively and managed scientifically, then the problems of combating alkalinity, eliminating drought and preventing waterlogging will be tackled in a comprehensive way of strong water to combat the drought. From the view point of metioned above to investigate the strategy of water control, it is important to transform the policy of drainage into storage or to combine the storage with the discharge.(4) The combination of wells with canals and the use of water in cycles for developing irrigation are effective methods of raising the utilization ratios of irrigation water and the ensuring degrees of water prorision. In the meanwhile, it is able to lighten the burden on the drainage in the irrigation area. These provide a precondition for the prevention and control of alkalinity, waterlogging and pollution of water sources caused by agricultural drainage. They seem to be some economic and rational water conservantion facilities. Also, the methods should be the most significant irrigation installations of the surface water use at most plain districts in northern China.