以水盐平衡理论为指导防治景泰灌区土壤次生盐渍化

对甘肃景泰灌区土壤次生盐渍化的发生机理进行了分析，认为次生盐渍化从本质上来说是一个诸多自然因素和人为因素共同作用下所造成的水盐不平衡问题，要防止和治理土壤次生盐渍化，就必须建立一种新的水盐平衡。在此基础上结合国内外盐渍化防治及盐渍土改良利用方面的发展趋势，笔者提出应该以水盐平衡理论为指导，以节水灌溉为前提，以地面覆盖和土壤培肥为基础，以井排系统与引黄灌水系统并网，井渠混灌，降低地下水位为突破口，通过对水分和肥力的调控和管理达到对盐分的调控和管理，使盐分在土体或灌区实现动态平衡，从而达到土壤盐渍化的预防和治理。

Policy of Secondary Salinization Prevention and Reclamation in Jingtai Irrigated Region under the Concept of Water-salts Balance

The mechanism of secondary soil salinization and the policy of prevention and reclamation in Jingtai irrigated area of Gansu province were discussed. It is believed that the salinization in the area is intrinsically the problem of water-salts unbalance, and its prevention and reclamation, therefore, should be under the guidance of the concept of water-salts balance. It is suggested that policy should be on the basis of minimum irrigation, soil mulching and straw and manure utilization, and the leading one of its measures should be to use high-salined groundwater as an accompaniment of river water, by the integration of the power-pumped-Yellow-River irrigation system and well-water irrigation system, to lower the watertable and reduce the irrigation cost. Thus the dynamic balance of salts, as well as the prevention and reclamation of salinization, will have been kept through the management of water and soil organic matter