大亚湾及邻近海域重金属污染的研究进展

A review on heavy metals contamination in Daya Bay and adjacent waters

综述了大亚湾及其邻近海域的海水、沉积物以及生物体中重金属的浓度水平、赋存形态、时空分布以及潜在生态风险等的研究进展。现有的研究表明,大亚湾海域海水中重金属污染程度较轻,但部分海域的Cu、Pb、Zn有超标现象;沉积物中重金属主要为残渣态,污染程度较轻,重金属含量呈增加的趋势,尤其是Hg、Cd的潜在危害较高;海产品中重金属浓度水平较低,但底栖生物中Cd含量水平存在一定的生态风险。综合现有研究资料,大亚湾海域有机重金属化合物的污染状况研究,同位素示踪技术分析重金属来源以及膜扩散梯度技术等在大亚湾重金属污染调查中的应用等方面仍需要进一步开展。

The characteristics of heavy metals contamination, such as the contents and forms, spatio-temporal distribution, and ecological risks were reviewed in the Daya Bay and its adjacent waters. Data on the levels of heavy metals in seawater, surface sediments and organisms have been summarized to evaluate the current pollution status of the Daya Bay. Results of studies indicated that heavy metals contamination in the Daya Bay was mild, with a slight pollution of Cu, Pb and Zn in certain sea waters. The major form of heavy metals in surface sediments was residual form. The contents of heavy metals were increased with time, while the main factors caused ecological hazard were Hg and Cd. The contamination level of heavy metals in organisms was safe, but content of Cd in benthos showed a potential ecological risk. Based on the current studies, further studies should be conducted on the investigation of the contamination of organic metal compounds, the sources of heavy metals using isotope tracer technique, and the forms of heavy metals using diffusive gradients in thin-films.