Influence of the porewater geochemistry on Fe and Mn assimilation in Laternula elliptica at King George Island (Antarctica)

A high input of lithogenic sediment from glaciers was assumed to be responsible for high Fe and Mn contents in the Antarctic soft shell clam Laternula elliptica at King George Island. Indeed, withdrawal experiments indicated a strong influence of environmental Fe concentrations on Fe contents in biv...

Full description

Bibliographic Details
Published in:Estuarine, Coastal and Shelf Science
Main Authors: Poigner, Harald, Monien, Patrick, Monien, Donata, Kriews, Michael, Brumsack, H.-J., Wilhelms-Dick, Dorothee, Abele, Doris
Format: Article in Journal/Newspaper
Language:unknown
Published: Elsevier 2013
Subjects:
Online Access:https://epic.awi.de/id/eprint/34389/
http://www.sciencedirect.com/science/article/pii/S0272771413004757
https://hdl.handle.net/10013/epic.42651
Description
Summary:A high input of lithogenic sediment from glaciers was assumed to be responsible for high Fe and Mn contents in the Antarctic soft shell clam Laternula elliptica at King George Island. Indeed, withdrawal experiments indicated a strong influence of environmental Fe concentrations on Fe contents in bivalve hemolymph, but no significant differences in hemolymph and tissue concentrations were found among two sites of high and lower input of lithogenic debris. Comparing Fe and Mn concentrations of porewater, bottom water, and hemolymph from sampling sites, Mn appears to be assimilated as dissolved species, whereas Fe apparently precipitates as ferrihydrite within the oxic sediment or bottom water layer prior to assimilation by the bivalve. Hence, we attribute the high variability of Fe and Mn accumulation in tissues of L. elliptica around Antarctica to differences in the geochemical environment of the sediment and the resulting Fe and Mn flux across the benthic boundary.