长江云阳段水质调查与评价

Survey and Assessment of the Water Quality in the Yunyang Section of Yangtze River

于2013年5月至2014年4月对长江云阳段水体的水温、p H值、溶解氧、高锰酸钾指数、氨氮和总磷共6项水质指标进行监测,依据《地表水环境质量标准(GB 3838-2002)》,选取溶解氧、高锰酸钾指数、氨氮和总磷作为水质参数,采用水质标识指数法进行综合水质评价。单因子水质标识指数评价结果表明,总磷为长江云阳段水体主要的水质污染指标,全年超标率为66.7%;溶解氧、氨氮和高锰酸钾指数全年达到Ⅱ类水质标准。综合水质标识指数评价结果表明,长江云阳段水质较稳定,综合水质全年为Ⅱ类,达到水环境功能区目标;平水期、枯水期水质总体优于丰水期。

Six water quality indicators, including water temperature, pH, dissolved oxygen, CODMn, ammonia nitrogen and total phosphorus, were monitored in the Yunyang section of Yangtze River from May 2013 to April 2014. Selecting dissolved oxygen, CODMn, ammonia nitrogen and total phosphorus as water quality parameters, the method of water quality identification index was used to assess the water quality status on the basis of environmental quality standards for surface water （GB 3838-2002）. The assessment results of single factor water quality identification index showed that total phosphorus was the main water pollution indicator and the rate that exceeded the national standard II was 66.7%, while dissolved oxygen, CODMn and ammonia nitrogen reached the water quality standard of II type water throughout the year. The assessment results of comprehensive water quality identification index showed that the water quality state of this water area was stable, the water quality throughout the year was Grade II, which achieved the goal of water environmental function, and the water quality of common and low water period was generally better than wet water period.