Jump to main content
Jump to site search

Issue 3, 2011
Previous Article Next Article

Littoral diatoms as indicators of recent water and sediment contamination by metals in lakes

Author affiliations

Abstract

We studied the response of benthic diatoms to recent metal contamination in littoral cores collected at 25 sites in 11 lakes situated at different distances from a smelter in the Rouyn-Noranda mining region (Quebec). Diatom response was described in terms of density, diversity, and taxonomic composition of the entire assemblages and as abundance of individual indicator taxa. Metal concentrations were measured in sediment and in the overlying water (as total dissolved and as free-ions). Sediment metal contamination was significantly higher in lakes located <10 km from the smelters than in lakes farther away. Such difference was not significant when metal concentrations in the overlying water were considered. Metal contamination did not affect diatom density, which indeed was highest in the most contaminated lake. Diversity (either measured as number of taxa or as Shannon and evenness indices) was instead significantly higher in lakes close to the smelter than elsewhere. Redundancy analysis indicated that diatom composition changed along a gradient in alkalinity (CO3) and one in sediment metal contamination (Cd, Hg, Cu). We identified three diatom taxa (Fragilaria construens var. venter, F. construens var. pumila, and Brachysira vitrea) that increased in relative and absolute abundance with metal contamination. Benthic diatom responses at the community (density, diversity, assemblage composition) and population levels (abundance of selected benthic taxa) were stronger to the sediment metal contamination than to the contamination of overlying water. Comparisons with available literature indicated that, for monitoring recent sediment contamination, diatoms in littoral sediments are preferable to invertebrates that mostly respond to overlying water. Diatoms in littoral cores are therefore unique as tools for monitoring recent contamination of lake sediments.

Graphical abstract: Littoral diatoms as indicators of recent water and sediment contamination by metals in lakes

Back to tab navigation

Supplementary files

Article information


Submitted
01 Jul 2010
Accepted
26 Nov 2010
First published
24 Dec 2010

J. Environ. Monit., 2011,13, 572-582
Article type
Paper

Littoral diatoms as indicators of recent water and sediment contamination by metals in lakes

A. Cattaneo, Y. Couillard, S. Wunsam and C. Fortin, J. Environ. Monit., 2011, 13, 572
DOI: 10.1039/C0EM00328J

Search articles by author

Spotlight

Advertisements