陆源污染物对龙江入海口水域环境质量的影响评价

福清龙江近几年水质严重恶化,携带大量污染物进入福清湾。本文利用2004~2005年对龙江入海口及其邻近水域的监测结果进行陆源污染物对龙江入海口环境质量的影响评价。结果表明,龙江入海口海水中的粪大肠菌群、磷酸盐、石油类、BOD5、无机氮、COD的含量均超过第二类海水水质标准,磷酸盐、无机氮、COD、BOD5甚至超过第四类海水水质标准。水中的重金属汞和铅阶段性的超标。龙江水经过邻近海域的海水稀释之后污染物浓度虽有所降低,但是到了福清湾顶平均污染指数仍然高达3.2。表层沉积物的几种污染物中只有邻近海域的石油类的含量超标,其他项目均符合海洋沉积物质量标准的要求。由于龙江入海口海域与福清湾是水产养殖区,受到污染的养殖环境会影响该养殖区水产品的质量,龙江污染的治理势在必行。

Evaluation on the Effect of Pollutant from Land on the Environment Quality in the Longjiang River Mouth

Longjiang-river in Fuqing was polluted seriously in the resent years.It brings large amount of pollutant into Fuqing bay.The influence of land source pollutant to the environment quality at the Longjiang-river mouth was evaluated by employing the monitoring result of 2004~2005.The results show that the contents of fecal coliform,phosphate,petroleum hydrocarbon,BOD_5,inorganic nitrogen and COD are gone beyond the second seawater standard.The contents of phosphate,inorganic nitrogen,COD,BOD_5 even gone beyond the fourth seawater quality standard.The content of heavy metal Hg and Pb in water gone beyond the second seawater quality standard periodically.Even though the content of pollutant in the water of Longjiang-river was diluted by seawater,the average water pollution index to the inlet of Fuqing bay is still as high as 3.2.The content of most of the pollutant in the sediment of Longjiang-river mouth accord with the first marine sediment quality standard,except petroleum hydrocarbon in the sediment of neighboring area gone beyond the standard.Since the Longjiang-river mouth and Fuqing bay are used for aquaculture,the polluted environment may lower the quality of aquatic products cultured in the area.It is necessary to control the pollution of Longjiang-river.