Jump to main content
Jump to site search

Issue 2, 2013
Previous Article Next Article

Changes in macroinvertebrate community structure provide evidence of neutral mine drainage impacts

Author affiliations

Abstract

Contamination of aquatic environments as a consequence of metal mining is an international issue. Most historic studies have considered the impact of acid mine drainage (pH < 6) on instream communities and comparatively little attention has been given to sites where drainage is typically circum-neutral (6 > pH < 8). Here, the impacts of historic mining activities on the benthic macroinvertebrate community of a circum-neutral river in Central Wales are assessed. Biotic and diversity indices, widely used for biomonitoring purposes, indicate aquatic macroinvertebrate assemblages within the Afon Twymyn to be in a good condition, despite severe metal contamination of bed sediments and river water. However, Canonical Correspondence Analysis identifies differences in community structure between mining impacted and unimpacted reaches of the river associated with chalcophile (Zn, Pb, Cu, Cd) and common (Fe and Mn) metals. Stream pH was not a significant factor structuring the macroinvertebrate community. Widely utilised macroinvertebrate indices failed to identify impacts at the community level because they either seek to identify impacts of a specific contaminant or are dependent on a model community response to a given stress. The nature of metal mine discharges is temporally complex, having highly variable chemical signatures and as a result, care is advised when interpreting and modelling community impacts. The use of standard macroinvertebrate biotic and diversity indices in the context of the EU Water Framework Directive could lead to erroneous classifications of aquatic ecosystem health when used for bio-monitoring rivers affected by neutral mine drainage where other indicators are unavailable.

Graphical abstract: Changes in macroinvertebrate community structure provide evidence of neutral mine drainage impacts

Back to tab navigation

Publication details

The article was received on 08 Jun 2012, accepted on 14 Nov 2012 and first published on 05 Dec 2012


Article type: Paper
DOI: 10.1039/C2EM30447C
Citation: Environ. Sci.: Processes Impacts, 2013,15, 393-404

  •   Request permissions

    Changes in macroinvertebrate community structure provide evidence of neutral mine drainage impacts

    P. Byrne, I. Reid and P. J. Wood, Environ. Sci.: Processes Impacts, 2013, 15, 393
    DOI: 10.1039/C2EM30447C

Search articles by author

Spotlight

Advertisements