Bioaccumulation of Trace Elements in the Organisms of Benthic Communities in the Reducing Environments of the Sea of Okhotsk

Sergey V Galkin,Liudmila L Demina

doi:10.5539/enrr.v8n3p182

Sergey V Galkin, Liudmila L Demina

Open Access

https://doi.org/10.5539/enrr.v8n3p182

Copy DOI

Abstract

A comparative study of the bioaccumulation of trace elements in benthic organisms inhabiting the area of methane seeps in the Deryugin Basin and nearby the Paramushir Island (Sea of Okhotsk) has been performed. The data pertain to both essential elements (Fe, Mn, Ni, Co, Cr, and Cu), which are necessary in certain concentrations for the metabolism of organisms, and nonessential heavy metals (Cd, Pb, and Hg), as well as As, a toxic metalloid. Dominating representatives of the bottom fauna from the Deryugin Basin (sea anemones, clams) were characterized by high bioaccumulation coefficients of most of the elements (&ge; n103), regardless of their biochemical properties. The use of the coefficient K, which characterizes the accumulation of trace elements in the soft tissues of bivalves relative to their shells, allowed us to detect differences in the bioaccumulation character. Symbiotrophic bivalves of the family Vesicomyidae from the Deryugin Basin were characterized by the accumulation of all of the trace elements mostly in soft tissues (gills, primarily) compared to the carbonate shells (coefficient K &gt; 1). We suppose that different effect of abiotic (biological availability of elements and water turbidity) and biotic (throphic strategy) factors of the habitats may probably be a reason of such phenomenon.

Highlights

Oceanic benthic communities perform various geochemical functions involving transformations of chemical elements
We have examined the principal bioaccumulation characteristics of heavy metals (Fe, Mn, Cu, Co, Cd, Ni, Cr, and Pb) and the metalloid As in the dominant taxa of macrobenthic communities at methane seeps in the Sea of Okhotsk
Most of these organisms are known to be trophically dependent on autochthonous organic matter, which is produced by chemoautotrophic bacteria in the course of chemosynthesis and methanotrophy (Jannasch & Wirsen, 1979; Roesijadi & Crecelius, 1984)

Summary

Introduction

Oceanic benthic communities perform various geochemical functions involving transformations of chemical elements. The recently launched development of Okhotsk Sea mineral resources (gas and oil mining and transportation) increases the probability of anthropogenic contamination of benthic Arctic marine ecosystems (Operation Report, 2011) This calls for studying the bioaccumulation of heavy metals and As (metalloid) and provides a basis for ecological monitoring. High iron concentrations were discovered at a distance of more than 3000 km from hydrothermal vents at the Central Indian Ridge and the East Pacific Rise. This element is stabilized via the synthesis of organic complexes and colloids in diluted hydrothermal solutions, and its precipitation is prevented (Bennet et al, 2011; Nishioka, Obata, & Tsumune, 2013)

Methods

Results

Conclusion