钦州湾春季水质营养状况分析与评价

Status Analysis and Evaluation on Nutrients in Qinzhou Bay in spring

根据2010年4月对钦州湾海域调查结果,分析并评价了该海域春季的营养状况。结果表明,表层海水中DIN和SiO3-Si都为茅尾海钦江入海口含量较高,PO4-P为茅尾海西南部沿岸增养殖区含量较高,DIN、PO4-P和SiO3-Si水平分布上均表现为湾内含量高于湾外。从营养结构看,与Justic等提出的营养盐化学计量限制标准比较,符合P限制条件,PO4-P可能成为浮游植物生长的潜在限制因子。根据营养状态指数评价模式和有机污染评价指数计算结果显示,2010年春季钦州湾海域营养水平属于中营养水平,有机污染程度属4级,表明钦州湾表层海水水质已达到中度污染。

The nutrient status was analyzed in Qinzhou Bay in spring according to the investigation result in April,2010.The results shown that the contents of inorganic nitrogen and silicate in surface seawater were relatively high in the Qinjiang River estuary of Maowei sea,the content of phosphate was relatively high in the alongshore waters of southwest of Maowei sea,which was aquatic culture area.The horizontal distributions of inorganic nitrogen,phosphate and silicate were higher in the inner Qinzhou Bay than in the outer Qinzhou bay.From the nutrition structure,the phosphate might become a potential factor to limit phytoplankton growth,and compared with limit standard of chemical measure for the nutrients,it is accorded with the limit condition of phosphate.According to the evaluation mode of eutrophication and the organic pollution index,the water quality was mesotropher in spring 2010,and the organic pollution degree was the fourth level in surface,which indicated the surface water quality of Qinzhou Bay had reached moderate pollution.