中国主要河口沉积物污染及潜在生态风险评价

Evaluation on potential ecological risk of sediment pollution in main estuaries of China.

采用单因子指数法和Hakanson生态风险指数法,通过分析长江口、珠江口、鸭绿江口和辽河口沉积物中典型污染要素PCB,Hg,Cd,Pb和As的含量,评价了上述河口沉积物的质量现状,定量确定了诸河口的潜在生态风险程度,结果表明,综合污染程度,长江口<鸭绿江口<珠江口<辽河口,长江口和鸭绿江口典型污染物的平均综合指数Cd分别为0.91和1.02,海域沉积物质量良好;而辽河口Cd污染程度较高(平均污染指数C if为3.38),珠江口As为中等污染参数(平均污染指数C if为1.57),潜在生态风险由低到高的排列顺序为鸭绿江口<长江口<珠江口<辽河口,Cd在辽河口具有较高的潜在生态风险(平均潜在风险参数E ir达101.53),而Hg在珠江口的局部海域具有中等潜在生态风险(潜在风险参数E ir达51.20).

Through analyzing the contents of typical pollutants (PCB, Hg, Cd, Pb and As) in sediments of Changjiang Estuary, Zhujiang Estuary, Yalujiang Estuary and Liaohe Estuary, with adopting the index number techniques of single factor and Hakanson ecological risk the quality status of these sediments were evaluated; and the potential ecological risks of these estuaries were determined quantitatively. The order of integrated pollution extents was Changjiang Estuary < Yalujiang Estuary <Zhujiang Estuary <Liaohe Estuary. The average integrated index number of typical pollutants Cd were 0.91 and 1.02 respectively, with rather good sediment quality in Changjiang Estuary and Yalujiang Estuary. However, Cd pollution extent was rather serious in Liaohe Estuary with average pollution index number of 3.38, and in Zhujiang Estuary As pollution was moderate with average pollution index number C if of 1.57. The sequence of potential ecological risk was Yalujiang Estuary < Changjiang Estuary < Zhujiang Estuary < Liaohe Estuary. Cd possessed rather high potential ecological risk in Liaohe Estuary (with an average potential risk parameter E ir of 101.53); while Hg possessed moderate potential ecological risk in partial sea-area of Zhujiang Estuary with the parameter E ir of 51.20.