9408243 Stahl In this project the structure of microbial communities of Lake Michigan anoxic sediments is being characterized using molecular methods (RNA sequencing and DNA probes), culture-based techniques, and measurements of rates of reduction of alternative electron acceptors. This research will identify and quantify the most abundant microbial populations at different depths in the sediments and relate them to depth-associated changes in redox state and respiratory mode. This research will greatly improve our understanding of the relationship between microbial community structure and anoxic microbial biogeochemical activity, such as anoxic respiration, sulfate reduction, metal reduction, and methanogenisis. These studies should also contribute to establishing the connections between sediment and water column activities. The results of this study will have application in understanding aquatic ecosystem function and in aquatic pollution studies.
