长江下游干流水环境现状及对策

Current situation of water environment of Yangtze River downstream and countermeasures

长江下游干流不仅要为区域内的经济发展提供必要的水资源 ,而且担负着提供南水北调东线工程水源的任务 ,其水环境的好坏 ,不仅制约着本区域的社会稳定和经济发展 ,也影响着全国的可持续发展。采用单因子水质类别法 ,对长江下游干流 11a的水质实测资料进行了分析和评价。得出如下结论 :(1)整个长江下游干流水环境质量多年来总体变化不大 ,尤其是中泓主流的水质常年基本能保持在Ⅱ类、Ⅲ类水质 ,但有恶化趋势 ;(2 )水环境污染主要集中在距江两岸约百米范围内的近岸水域 ,其水质常年在Ⅲ类甚至Ⅳ类、Ⅴ类以下。

The downstream of Yangtze River is not only used to provide neccessary water resources for economy development of the vicinity regions,but also it will take charge of a task of water supply for the East Line of Water Diversion project from South to North China. So, the water quality of downstream Yangtze River would affect the sustainable development of our country. Monitoring data of Yangtze River water quality in past 11 years were analyzed and assessed by single factor exponent mothed. It is concluded that:(1) the water quality of Yangtze River downstream is insignificantly changed as a whole, yet it has the tendency of deterioration. The water quality degree at middle threads of stream belongs to Ⅱ to Ⅲ. (2) the main pollution zones are in water field of about 100 m from banks, the degree belongs to Ⅲ,Ⅳ or Ⅴ. Based on above analyses,the countermeasures are presented for treating pollution and improving water quality.