舟山群岛岩相潮间带日本笠藤壶重金属富集及其污染评价

Metal Content and Contamination Assessment in Tetraclita japonica from the Rocky Intertidal Zone of Zhoushan Islands

日本笠藤壶是舟山群岛岩相潮间带的广布种,对重金属具有较强的富集能力,是生物监测海洋重金属污染的良好指示种。为了探讨舟山海域重金属的污染状况及其在海洋生物体内的富集规律,本文分析了该种对Cu、Pb、Cd、Cr、As和Hg的富集能力。结果表明,日本笠藤壶体内Cu的含量显著高于Pb、Cd、Cr、As和Hg的含量,且Pb和Hg富集量之间呈显著的正相关关系。根据日本笠藤壶体内积累的重金属总量,在本研究的7个样点中,岱山和小洋的日本笠藤壶受重金属污染程度高。与海洋贝类生物质量标准相比,除Pb和Hg超过各自的第二类标准值外,日本笠藤壶体内Cu、Cd、Cr和As含量都没有超过各自的第二类标准值,这表明目前舟山群岛海域日本笠藤壶受Pb和Hg的污染较为严重,受Cu、Cr、Cd、As的污染较轻。

Tetraclita japonica is a good bio-monitor for the marine heavy metal pollution. Tetraclita japonica is a fouling organism and commonly distributes in the rocky intertidal zone of Zhoushan Islands, which has high accumulation abilities of heavy metal. In order to investigate heavy metal pollution in Zhoushan sea area and its enrichment regularity in marine organisms, the accumulation abilities of Cu, Pb, Cd, Cr, As, and Hg in Tetraclita japonica are analyzed. The results show that content of Cu are much higher than that of Pb, Cd, Cr, As, and Hg in Tetraclita japonica, and there is also a significantly positive correlation between Pb and Hg content. According to its total quantity of accumulated metals, it could be seen that Tetraclita japonica from Daishan and Xiaoyang Islands are most severely polluted by heavy metal among the seven sampling sites studied. In comparison with the biological quality criteria for marine bivalves, metal contents in Tetraclita japonica are almost below the second standard value except contents of Pb and Hg. By contrast to the heavy metals of Cu, Cr, Cd, and As, Tetraclita japonica in Zhoushan Islands is contaminated by Pb and Hg quite seriously.