Institute of Urban Environment, Chinese Academy of Science, Xiamen, 361021, China,
Environ Monit Assess. 2014 Nov;186(11):7023-33. doi: 10.1007/s10661-014-3907-2. Epub 2014 Jul 6.
Studies of heavy metal contamination and ecological risk in estuaries are an important emerging area of environmental science. However, there have been few detailed studies of heavy metal contamination that concern the spatial variation of heavy metal levels in water, sediment, and oyster tissue. Because of the effective uptake of heavy metals, cultured oysters are a cheap and effective subject for study. This study, conducts an experiment in the Er-Ren river to examine the biological uptake of heavy metals in farmed, cultured oysters. The distribution of copper, zinc, lead, cadmium, and arsenic concentrations in water, sediment, and oysters from the Er-Ren river is also evaluated. By sequential extraction of the sediments, the following order of mobilities is found for heavy metals Pb > Cd > As > Zn > Cu. The highest percentages of heavy metals are found in the residual phase. The mean uptake rates for young oysters are 7.24 mg kg(-1) day(-1) for Cu and 94.52 mg kg(-1) day(-1) for Zn, but that for adult oyster is 10.79 mg kg(-1) day(-1) for Cu and 137.24 mg kg(-1) day(-1) for Zn. With good policies and management, the establishment of cultured oyster frames in these contaminated tributaries and near shore environments is a potential method for removing Cu and Zn and protecting the coast.
河口重金属污染与生态风险研究是环境科学中一个新兴的重要领域。然而，对于水体、沉积物和牡蛎组织中重金属水平的空间变化等重金属污染问题，仅有少数详细研究。由于牡蛎对重金属具有较强的吸收能力，因此养殖牡蛎是一种廉价且有效的研究对象。本研究在二仁溪进行了一项实验，以检验养殖牡蛎对重金属的生物吸收情况。同时，还评估了二仁溪水体、沉积物和牡蛎中铜、锌、铅、镉和砷浓度的分布情况。通过对沉积物的连续提取，发现重金属的迁移顺序为 Pb > Cd > As > Zn > Cu。重金属的最大比例存在于残渣相中。幼牡蛎的平均摄取率分别为 Cu 为 7.24 mg kg(-1) day(-1)，Zn 为 94.52 mg kg(-1) day(-1)，而成牡蛎的摄取率分别为 Cu 为 10.79 mg kg(-1) day(-1)，Zn 为 137.24 mg kg(-1) day(-1)。通过良好的政策和管理，在这些受污染的支流和近岸环境中建立养殖牡蛎框架，是去除 Cu 和 Zn 并保护海岸的一种潜在方法。
