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 d iversity in aquifers might be enhanced by landfill leachate infiltration. T o study this hypothesis, groundwater samples were taken near the Banisveld landfill, The Netherlands. Based on hydrochemical parameters, the samples c lustered into two groups. One group corresponded to polluted samples from t he plume of landfill leachate and the second group to clean samples from ou tside the plume. Most Probable Number-Biolog was used to select Eco Biolog plates with similar inoculum densities. Analysis of substrate utilization p rofiles of these plates revealed that anaerobic microbial communities in po lluted 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 d iversity were significantly enhanced in the plume of pollution. This study shows that community-level physiological profiling is a useful and simple t ool to distinguish between anaerobic microbial communities in and near a la ndfill leachate plume.