9617702 Reysenbach In order to better understand the chemical processes occurring in hydrothermal plumes and develop predictive models of hydrothermally-derived chemical fluxes, it is necessary to characterize the effects that microbial activity have on plume chemistry. The main objectives of this project are: 1. To characterize the diversity and define the structure of microbial communities associated with chemical fluxes within the hydrothermal plume environment, utilizing molecular phylogenetic techniques; 2. To map changes in the diversity and structure of the microbial community as the plume ages; 3. To examine the abundance and activity of specific members of the plume microbial community through the use of fluorescent rRNA probes. This research will provide significant new information about these poorly defined microbial effects which in turn will aid in the development of realistic models of chemical fluxes in hydrothermal systems. A fourth objective of this project is to provide an opportunity for the new Ph.D. (E. McLaughlin) to broaden her research experience as defined in the RIDGE program announcement. A postdoctoral position in Dr. Reysenbach's laboratory will allow E. McLaughlin to learn and utilize molecular phylogenetic techniques. Thus, fostering "cross-disciplinary fertilization" by combining the molecular phylogenetic expertise of the host laboratory with the geochemical knowledge obtained during the candidate's thesis work.
