江苏湖泊富营养化特征、成因及解决途径

CHARACTERISTICS AND CAUSE OF LAKE EUTROPHICATION IN JIANGSU PROVINCE WITH SUGGESTIONS ON ITS CONTROL MEASURES

应用湖泊营养类型评价标准对江苏省主要湖泊富营养化进行了评价,以区域环境特征对苏南和苏北湖群及城郊湖泊富营养化现状、发生原因及对策进行了探讨。分析表明:城郊湖泊全部为富营养和重富营养水平,苏北湖群营养程度已接近苏南湖群,呈中富营养中期,太湖东部营养程度较之太湖西部高出一个营养级别以上。苏北湖群多为过水性湖泊,易受高浓度工农业污水脉冲式入湖影响;苏南湖群污染成因则相对较复杂,主要受城镇生活和工农业生产高污染负荷的氮磷排放影响。严格控制流域内各类污染源的源头污染物排放量、充分利用河网湿地净化功能、适度进行湖内污染底泥疏浚和生态重建工程,对控制江苏湖泊富营养化将是较有效的途径。

On the basis of the trophic evaluation criterion of lakes,the eutrophication status of most lakes in Jiangsu Province were estimated,with the analysis on the cause of formation and controlling ways in south area and north area in Jiangsu, as well as in outskirts of cities. It is indicated that all outskirt lakes were eutrophic or hyper-eutrophic; the lakes in north Jiangsu were meso-eutrophic, and similar to the lakes in south Jiangsu. The trophic degree of lakes in east Lake Taihu was one grade higher than those in the west. The majority of lakes in the north in Jiangsu are water-carrying, liable to suffer from industrial and agricultural waste water in pulse discharge. The cause of lake eutrophication in south Jiangsu is more complex and they were mainly impacted by town effluent and industrial and agricultural waste water which hold nitrogen and phosphorus in high concentration. The efficient ways to control eutrophic lakes in Jiangsu Province is to strictly controlling headstream discharge of the pollutants from the various pollution sources in catchments, adequate application in wetland purification function of the net-rivers and to perform some environmental engineering of sludge dredging and ecological reconstruction in moderation.