鄱阳湖水环境演变特征研究

鄱阳湖水质安全是鄱阳湖生态经济区规划实施的重要物质基础，也是长江流域生态安全的重要组成。本文通过收集湖区主要水质监测断面2003-2008年逐月监测资料，采用单因子评价、湖泊富营养化评价、季节性肯达尔检验等分析主要河流、湖泊水环境演变特征。研究表明，鄱阳湖区现状水质较好，全年、汛期、非汛期的I-Ⅲ类水面积比例分别为63．9％、99．3％、40．8％，水体处于中营养一轻度富营养化状态。赣江、抚河、修河等人湖控制断面I一Ⅲ类水比例高于90％，乐安河、长江等控制断面I-Ⅲ类水质比例高于70％，湖口断面现状水质较差，Ⅳ类及以下水质比例高于30％。随着鄱阳湖流域社会、经济的发展，部分水质断面污染物浓度增加，湖泊I-Ⅱ类水面积比例呈下降趋势，需要采取有效措施，减少流域污染物排放量和人湖量，实现一湖清水的目标，为水利枢纽工程实施提供良好的水环境条件。

Characteristics of water environment in Poyang Lake

Poyang Lake water quality is an important material basis for Poyang Lake Ecological Economic Zone planning and implementation, and is an important component of the Yangtze River watershed ecological security. With the requirement of the Poyang Lake area of social and economic development, Jiangxi Province proposed the construction of water control projects in outlets of the lake, which would influence the water environment of the Poyang Lake. This article primarily collects the water quality monthly monitoring data （including major rivers, lakes） from 2003 to 2008, through single factor evaluation, lake eutrophi- cation and seasonal Kendall test methods to assess water environment characteristics. The results show that the water quality of the Poyang Lake area is in better situation. The average year, the flood season andnon-flood season of 1 -Ⅲtype of water area ratio are 63.9%, 99.3%, 40.8% respectively, and lake nutrients are in the nutrition-mild eutrophication. At the same time, Gan river, Fu river, Xiu river water quality status of control section are better, with I- Ⅲ class of water higher than 90%, and Le An River and the Yangtze River Grade I- Ⅲ higher than 70%. Hukou section is in poor water quality status, with IV class and below the water quality higher than 30%. With the Poyang Lake area of social and economic development, pollutant concentration of the rivers and lakes increasd, which resulted in I -II type water ar- ea ratio of the lake decreasing. This needs to take effective measures to reduce pollutant emissions to provide a good water environment for hydro project implementation.