Distribution of dissolved species and suspended particulate copper in an intertidal ecosystem affected by copper mine tailings in Northern Chile
Distribution of dissolved species and suspended particulate copper in an intertidal ecosystem affected by copper mine tailings in Northern Chile
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DOI：
10.1016/j.marchem.2006.03.002
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发表时间：
2006-10-05
期刊：
影响因子：
3
通讯作者：
Correa, Juan A.
中科院分区：
文献类型：
--
作者：
Andrade, Santiago;Moffett, James;Correa, Juan A.
智利北部Chanaral附近的海岸线是世界上铜污染最严重的地区之一，这是由于60多年来采矿活动排放的污染物造成的。研究Cu的形态是为了确定高污染地区有机络合的重要性，并评估Cu对海洋生物可能的生理影响。测量了高达500 nM的溶解Cu浓度，完全饱和有机配体并导致游离Cu2+浓度超过10(-8)m。这些值高于任何其他海洋环境中报道的值，并且由于它们发生在广泛的区域，为研究Cu对海洋生态系统的影响提供了独特的机会，并看到Cu在其主要形态为无机时的行为。我们发现，在Chauaral和邻近的低Cu地区之间，游离Cu2+有很强的梯度，在这些地区，物种形成主要是有机络合。在污染区域，铜在悬浮颗粒上的分配也显著增加，这与先前的研究结果一致，即有机配体在溶解相中稳定了铜，而“多余”的铜被迅速清除。尽管沿着这条开放的海洋海岸线存在固相分配和平流过程，但这些高溶解Cu浓度仍然存在，这表明Cu输入系统仍然非常大。测量采用阳极溶出伏安法，用涂有Nafion的薄汞膜进行，以前的工作人员已经证明，这可以减轻由于无意中减少有机络合物而引起的数据模糊。我们的研究结果表明，这是一个有用的方法污染系统。(c) 2006 Elsevier b.v.版权所有
The coastline near Chanaral in Northern Chile is one of the most highly Cu-contaminated zones in the world due to discharges from mining activities for more than 60 years. The speciation of Cu has been studied to determine the importance of organic complexation in highly contaminated areas, and to assess the likely physiological impacts of Cu on marine organisms. Dissolved Cu concentrations of up to 500 nM were measured, completely saturating organic ligands and leading to free Cu2+ concentrations in excess of 10(-8) M. These values are higher than those reported in any other marine environment, and because they occur over an extensive area, provide a unique opportunity to study the effects of Cu on marine ecosystems and to see how Cu behaves when its speciation is predominantly inorganic. We found strong gradients in free Cu2+ between Chauaral and adjacent areas with lower Cu, where speciation is dominated by organic complexation. There is also a significant increase in the partitioning of Cu onto suspended particles in the contaminated areas, consistent with previous studies that showed that organic ligands stabilize Cu in the dissolved phase, whilst "excess" Cu is rapidly scavenged. Those high dissolved Cu concentrations persist in spite of solid phase partitioning and advective processes along this open-ocean coastline, suggesting that Cu inputs into the system are still very large. Measurements were made using anodic stripping voltammetry with a thin mercury film coated with Nafion, which previous workers have shown can mitigate ambiguity in the data arising from inadvertent reduction of organic complexes. Our findings suggest that this is a useful methodology for contaminated systems. (c) 2006 Elsevier B.V All rights reserved.