Mercury in lagoons: An overview of the importance of the link between geochemistry and biology

Shallow-water lagoons, which are common features along coastlines, are important sites for elemental cycling in this environmentally-sensitive terrestrial–marine interface. Factors governing mercury (Hg) cycling in these lagoons are poorly characterized, but critical to understanding the links betwe...

Full description

Saved in:
Bibliographic Details
Published in:Estuarine, coastal and shelf science coastal and shelf science, 2012-11, Vol.113, p.126-132
Main Authors: Faganeli, Jadran, Hines, Mark E., Covelli, Stefano, Emili, Andrea, Giani, Michele
Format: Article
Language:English
Subjects:
Brackish
Cycles
Dynamical systems
Dynamics
Lagoons
Links
Mercury
methylation
methylmercury
Microorganisms
sediments
Sulfur
trophic transfer
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Shallow-water lagoons, which are common features along coastlines, are important sites for elemental cycling in this environmentally-sensitive terrestrial–marine interface. Factors governing mercury (Hg) cycling in these lagoons are poorly characterized, but critical to understanding the links between sources and higher trophic levels, that are ultimately vectors of human exposure in lagoon environments. This article discusses the processes controlling the fate of Hg from various sources, including methylation of Hg, demethylation of methylmercury, and benthic fluxes of Hg species in three of the most thoroughly studied lagoons worldwide, namely Thau (France), Venice (Italy) and Marano and Grado (Italy). Although each lagoon system experiences differences in sources of Hg and details of how Hg is transformed and transported, Hg in each system is strongly affected by biogeochemical transformations of other elements, especially redox sensitive, microbially important elements such as sulphur, iron and manganese, and their interaction with organic matter. The shallow nature of lagoons and the rapid rates of microbially mediated organic matter decomposition result in seasonally dynamic processes that influence Hg bioavailability. Despite considerable work to date, the current understanding of Hg dynamics in lagoon ecosystems, through Hg distribution, MeHg production and degradation, and trophic transfer, is still limited and more research is needed to link all subparts into a general coherent picture.
ISSN:0272-7714
1096-0015
DOI:10.1016/j.ecss.2012.08.021