小洋山码头潮间带地区海水及生物体内重金属污染特征的分析与评价

Evaluation and Analysis on Pollution Characteristic of Heavy Metal in Seawater and Intertidal Marine Animals from Xiaoyangshan

为探明洋山港运行对周边海域的环境影响,本文对洋山港码头所在地小洋山港潮间带地区表层海水及生物体内重金属的污染程度进行深入分析与评价。结果表明,表层海水中重金属以Zn和Hg的污染为主;生物体内主要累积重金属为Cu和Zn,其中小结节滨螺体内重金属含量最高,富集系数最大,可作为小洋山码头地区海水重金属生物可利用性的指示物种;生物体内重金属形态和组织分布的结果表明,Cu、Pb、Cd和Zn以水溶态存在的比例较小,且主要存在于肌肉组织中,而As和Hg主要以不溶态的形式存在于非肌肉组织中;重金属在不同生物种类体内分布的差异显著,粗糙滨螺体内重金属以水溶态存在的比例最大,海蟑螂的重金属大多都存在于其肌肉组织中。食用僧帽牡蛎肌肉部分的日限制量(265.80g)明显高于食用其全部软组织(46.74g),且前者还与背景海水的重金属污染特征有较好的一致性,能较准确的反映海水重金属的污染程度。

In order to investigate the environmental impacts caused by the operation of the Yangshan Port on surrounding waters, heavy metals in surface seawater and intertidal marine animals was ana lyzed and evaluated in detail in this study. The results indicated that Zn and Hg were the dominated pollution elements, meanwhile Cu and Zn were the main heavy metals accumulated in the marine ani- mals. The content and enrichment factor of heavy metals in Nodilittorina exigua was the highest, therefore it can be adopted as the biological indicator of heavy metal in Yangshan port. The results of chemical speciation and tissue distribution in marine animals showed that water soluble proportion of Cu, Cd, Zn, and Pb were low and mainly found in mussel tissues, however As and Hg were mainly found in non-mussel part in the form of insoluble one. The differences of distributions and speciations of heavy metals among all animals were significant, and heavy metals in Littoraria scabra and Ligia ex- otica were in the presence of water soluble and mainly found in the mussel tissues. The daily limit amount of Ostrea cucullata mussel （265.80g） was significantly higher than that of soft tissue （46.74g）, and the former can more accurately reflect the heavy metals pollution degrees of sea water in Yangshan Port.