三峡水库蓄水前后长江部分江段水质变化

Water Quality of Different Sectors of Yangtse River Before and After Three Gorges Reservoir Keeps 135 m Water Level

目的了解三峡工程135m水位蓄水后长江部分江段水质的变化情况。方法以长江丰都至巫山段的6个城市的8个水质断面作为监测点,按照水质采样方案设计技术规定(GB12997-1991)进行布点,在平水期和丰水期共采集水样96份,分别按照相应的国家标准方法进行pH、溶解氧、生化需氧量、化学耗氧量、挥发酚、总氰化物、砷、汞、六价铬、石油类、铅、镉、氨氮、高锰酸盐指数、总磷、总氮等16项水质指标的检测,将监测结果与往年同期总体水质和背景浓度进行比较。结果三峡水库135m蓄水前后总体水质仍属II、III类无明显变化。影响库区总体水质的主要污染因子是总磷、总氮。结论三峡水库135m蓄水未对库区长江水质造成显著的负面影响。

Objective To know water quality of different sectors of Yangtse River after the Three Gorges reservoir kept 135 m water level. Methods Eight locations in six cities sectors(Fengdu,Wushan) of Yangtse River were selected as the monitor point and water samples were collected according to the related national standard (GB12997,1991). 96 samples were collected in May and August, 16 parameters (pH, DO, BOD5, CODCr, Ar,OH, TCN,As, Hg, Cr6+, oil, Pb, Cd, NH3,N, TP, TN, CODMn) of every sample were detected based on the methods documented in the related national standards and compared the results with the results of past years. Results 135 m water level had no significant influence on the water quality of different sectors of Yangtse River(II, III grade). Water quality had no significant change before and after 135 m water level emerged the primary contaminations which effect water quality were total nitrogen and total phosphors. Conclusion No significant change of water quality of Yangtse River has been seen after the Three Gorges reservoir kept 135 m water level.