Linking microbial community structure to pollution : Biolog-substrate utilization in and near a landfill leachate plume

Previously, we observed that microbial community structure and functional diversity in aquifers might be enhanced by landfill leachate infiltration. To study this hypothesis, groundwater samples were taken near the Banisveld landfill, The Netherlands. Based on hydrochemical parameters, the samples clustered into two groups. One group corresponded to polluted samples from the plume of landfill leachate and the second group to clean samples from outside the plume. Most Probable Number-Biolog was used to select Eco Biolog plates with similar inoculum densities. Analysis of substrate utilization profiles of these plates revealed that anaerobic microbial communities in polluted samples clustered separately from those in clean samples. Especially substrates containing an aromatic nucleus were more utilized by microbial communities in the leachate plume. Both substrate richness and functional diversity were significantly enhanced in the plume of pollution. This study shows that community-level physiological profiling is a useful and simple tool to distinguish between anaerobic microbial communities in and near a landfill leachate plume.