Editor: Max Häggblom
Spatial heterogeneity of dechlorinating bacteria and limiting factors for in situ trichloroethene dechlorination revealed by analyses of sediment cores from a polluted field site
Article first published online: 26 NOV 2009
© 2009 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Ecology
Volume 71, Issue 3, pages 444–459, March 2010
How to Cite
Dowideit, K., Scholz-Muramatsu, H., Miethling-Graff, R., Vigelahn, L., Freygang, M., Dohrmann, A. B. and Tebbe, C. C. (2010), Spatial heterogeneity of dechlorinating bacteria and limiting factors for in situ trichloroethene dechlorination revealed by analyses of sediment cores from a polluted field site. FEMS Microbiology Ecology, 71: 444–459. doi: 10.1111/j.1574-6941.2009.00820.x
- Issue published online: 1 FEB 2010
- Article first published online: 26 NOV 2009
- Received 15 July 2009; revised 9 November 2009; accepted 9 November 2009.Final version published online 23 December 2009.
- in situ dechlorination;
- spatial heterogeneity;
- reductive dechlorination;
- natural attenuation
Microbiological analyses of sediment samples were conducted to explore potentials and limitations for bioremediation of field sites polluted with chlorinated ethenes. Intact sediment cores, collected by direct push probing from a 35-ha contaminated area, were analyzed in horizontal layers. Cultivation-independent PCR revealed Dehalococcoides to be the most abundant 16S rRNA gene phylotype with a suspected potential for reductive dechlorination of the major contaminant trichloroethene (TCE). In declining abundances, Desulfitobacterium, Desulfuromonas and Dehalobacter were also detected. In TCE-amended sediment slurry incubations, 66% of 121 sediment samples were dechlorinating, among them one-third completely and the rest incompletely (end product cis-1,2-dichloroethene; cDCE). Both PCR and slurry analyses revealed highly heterogeneous horizontal and vertical distributions of the dechlorination potentials in the sediments. Complete reductive TCE dechlorination correlated with the presence of Dehalococcoides, accompanied by Acetobacterium and a relative of Trichococcus pasteurii. Sediment incubations under close to in situ conditions showed that a low TCE dechlorination activity could be stimulated by 7 mg L−1 dissolved carbon for cDCE formation and by an additional 36 mg carbon (lactate) L−1 for further dechlorination. The study demonstrates that the highly heterogeneous distribution of TCE degraders and their specific requirements for carbon and electrons are key issues for TCE degradation in contaminated sites.