青岛崂山湾海域营养盐时空特征及年际变化规律

Temporal-spatial Characteristics and Inter-annual Variation of Nutrients in Laoshan Bay,Qingdao

根据2012年5月至2015年3月对青岛崂山湾12个航次的调查资料,分析了DIN、PO4-P和COD的时空特征及年际变化规律。运用单因子指数、富营养化指数和海水有机污染状况指数等方法评价了该海域富营养化状况。结果显示：NO3-N为DIN的主要存在形式,DIN为崂山湾的主要污染因子,12个航次平均DIN浓度66.67%。符合一类海水水质标准;PO4-P及COD浓度均符合一类海水水质标准。N/P近20年总体呈上升趋势,该海域已由氮限制水体转变为磷限制水体,营养盐结构发生了根本性变化。富营养化指数均值为0.42,海水有机污染指数变化区间为-0.35-1.50,较富营养化指数法、海水有机污染指数法结论更为客观。

According to twelve investigations in the Laoshan Bay,Qingdao,in May 2012 to March 2015,including DIN、PO4-P and COD,Temporal-Spatial Characteristics and inter-annual variation of nutrients were studied,and the eutrophication degree of the Laoshan Bay was assessed by single factor index,eutrophication index andorganic pollution comprehensive index. The results showed that NO3-N was the chief form of DIN,and DIN was the principal contamination parameter for water quality of the Laoshan Bay. The average concentration of DIN in66. 67% met the grade Ⅰ of Seawater Quality Standard,PO4-P and COD in 100% met the grade Ⅰ of Seawater Quality Standard oftwelve investigations. The N： P ratio increases in the last twenty years,and the limitation factor of the Laoshan Bay was phosphorus rather than nitrogen,the nutrient structure was changed greatly. The eutrophication index in average rate of twelve investigations is 0. 42,and the organic pollution comprehensive index in change interval of twelve investigations is- 0. 35 - 1. 50. The results of organic pollution comprehensive index is more objective than eutrophication index.