沈家门渔港营养盐现状及变化评价

Assessment on Nutrient Status and Changes in Shenjiamen Fishing Port

根据2006～2011年沈家门渔港海域水质监测结果,对氮磷营养盐的污染现状、年际变化进行了分析,并进行营养状态指数法和潜在性富营养化程度评价。结果表明:沈家门渔港海域无机氮和磷酸盐含量均呈逐年上升趋势,尤其是无机氮含量较高,为0.453～0.732 mg/dm3,已超国家第四类海水水质标准。营养指数E为3.73～13.10,水体处于富营养化状态且呈逐年加重趋势,其中,2008年和2010年属于富营养等级,其它年份均为磷中等限制潜在性营养等级(VP);N/P值为25.9～38.4,高于正常海水的Redfield比值,磷酸盐成为浮游植物生长繁殖的主要限制因子。

The nutrient status and change were evaluated in Shenjiamen Fishing Port,according to the investigation result from 2006 to 2011.The result showed that the concentration of inorganic nitrogen and phosphate raised year after year,especially the concentration of inorganic nitrogen was high,exceeded the fourth grade of sea water quality standard.The nutrition index（E） was 3.73～13.10,the sea area had been in eutrophication state and decreased gradually.The ratio of N/P in the water was 25.9～38.4,which was much higher than that of Redfield ratios,and the inorganic phosphate was to be limiting factor.