中国沿海地区海水入侵现状与分析

THE SITUATION AND ANALYSIS OF SALINITY INTRUSION IN COASTAL AREAS,CHINA

首先介绍了我国存在着严重海水入侵灾害的三大河三角洲——长江三角洲、珠江三角洲、老黄河三角洲(莱州湾地区)海水入侵现状。长江口和珠江口海水入侵主要受河流入海径流量和河口潮汐影响,莱州湾地区海水入侵的产生则主要是人类过量开采地下淡水所致。地下淡水和咸水之间存在着一个动态平衡的混合界面,淡水储存一旦减少,平衡状态被打破,该界面便会向陆移动,最终产生海水入侵。海水入侵的发生受着诸多因素制约。在中国沿海地区,地下淡水的储备与人类的用水需求之间存在着矛盾,人类过量开采地下淡水是产生海水入侵的主导因素。因而开源节流、人工回灌地下淡水、阻隔水流等措施在防治海水入侵方面是行之有效的。

This paper sets forth the present situation of salinity intrusion in areas of Yangtze Delta, Zhujiang Delta and Huanghe Delta (Laizhou Bay). The salinity intrusion in the former two areas is under the control of runoff and tide. But the main reason of the salinity intrusion in Laizhou Bay is the excessive drawing of underground fresh water. There is a dynamic equilibrium interface between underground fresh water and salt water. If the storage of fresh water decreases and the equilibrium is lost, the salinity intrusion occurs. This is controlled by several factors. There is a conflict between the storage of underground fresh water and the demand of human being for it. Excessive underground water drawing is the main factor that results in salinity intrusion. So, looking for new source of fresh water, water saving, recharging fresh water artificially, separating fresh water and salt water are useful to prevent the generation and development of this hazard.