Microbial communities in a porphyry copper tailings impoundment and their impact on the geochemical dynamics of the mine waste

Détails

ID Serval
serval:BIB_DEBCCF46BF75
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Microbial communities in a porphyry copper tailings impoundment and their impact on the geochemical dynamics of the mine waste
Périodique
Environmental Microbiology
Auteur(s)
Diaby N., Dold B., Pfeifer H.R., Holliger C., Johnson D.B., Hallberg K.B.
ISSN-L
1462-2912
Statut éditorial
Publié
Date de publication
2007
Peer-reviewed
Oui
Volume
9
Pages
298-307
Langue
anglais
Résumé
The distribution and diversity of acidophilic bacteria of a tailings
impoundment at the La Andina copper mine, Chile, was examined. The
tailings have low sulfide (1.7% pyrite equivalent) and carbonate (1.4%
calcite equivalent) contents and are stratified into three distinct
zones: a surface (0-70-80 cm) `oxidation zone' characterized by low-pH
(2.5-4), a `neutralization zone' (70-80 to 300-400 cm) and an unaltered
`primary zone' below 400 cm. A combined cultivation-dependent and
biomolecular approach (terminal restriction enzyme fragment length
polymorphism and 16S rRNA clone library analysis) was used to
characterize the indigenous prokaryotic communities in the mine
tailings. Total cell counts showed that the microbial biomass was
greatest in the top 125 cm of the tailings. The largest numbers of
bacteria (10(9) g(-1) dry weight of tailings) were found at the
oxidation front (the junction between the oxidation and neutralization
zones), where sulfide minerals and oxygen were both present. The
dominant iron-/sulfur-oxidizing bacteria identified at the oxidation
front included bacteria of the genus Leptospirillum (detected by
molecular methods), and Gram-positive iron-oxidizing acidophiles related
to Sulfobacillus (identified both by molecular and cultivation methods).
Acidithiobacillus ferrooxidans was also detected, albeit in relatively
small numbers. Heterotrophic acidophiles related to Acidobacterium
capsulatum were found by molecular methods, while another
Acidobacterium-like bacterium and an Acidiphilium sp. were isolated from
oxidation zone samples. A conceptual model was developed, based on
microbiological and geochemical data derived from the tailings, to
account for the biogeochemical evolution of the Piuquenes tailings
impoundment.
Création de la notice
08/10/2012 17:09
Dernière modification de la notice
20/08/2019 17:03
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