Discount Trophic influences of metal accumulation in natural pollution laboratories at deep-sea hydrothermal vents of the Mid-Atlantic Ridge [An article from: Science of the Total Environment, The]

Sunday, November 13, 2011

Discount Trophic influences of metal accumulation in natural pollution laboratories at deep-sea hydrothermal vents of the Mid-Atlantic Ridge [An article from: Science of the Total Environment, The]

Trophic influences of metal accumulation in natural pollution laboratories at deep-sea hydrothermal vents of the Mid-Atlantic Ridge [An article from: Science of the Total Environment, The]

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Overview : This digital document is a journal article from Science of the Total Environment, The, published by Elsevier in 2007. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
This study reports on the concentration of both, toxic (Hg) and essential (Fe, Cu, Zn) metals in representative species, at four hydrothermal vents along the Mid-Atlantic Ridge (MAR) corresponding to the different exposure conditions that are the result of contrasted geological setting and different depths along the ridge axis. Macro fauna collected from these vent sites showed markedly different whole tissue concentration of metals reflecting exposure levels. Bio-transfer of metals within a typical hydrothermal food chain was investigated. There were trophic level-specific variations in essential metal accumulation showing a general trend within which the secondary consumers (predators/scavengers) and primary consumers (filter-feeder/symbiont reliant species like the mixotrophic mollusks and sponges all having metal concentrations above those in passive suspension-feeders such as echinoderms, gorgonians) accumulated highest concentrations of all elements followed by primary producers such as endosymbiont bacteria. Mercury accumulation followed a somewhat different sequence among the same taxonomic groups: top concentrations in the symbiont-bearing filter-feeder bivalves >crustaceans> sponges > bacteria > echinoderms, gorgonians and tunicates. There were no indications of biomagnification of Hg, Cu and Zn unlike Fe that showed positive transference factors (TF) along two trophic levels of a typical chain at Menez Gwen.