SGER: Microorganisms in Sub-ice Sediments from The Western Antarctic Ice Sheet, Ice Stream C

University Of California-Riverside, Riverside CA

Investigators

Abstract

Ice streams of the Western Antarctic Ice Sheet (WAIS) are thought to have unfrozen, water-saturated sediments at their base. Similar water-rock-ice interfaces beneath Arctic and alpine glaciers have been demonstrated to house abundant microbial communities which, through their metabolic activities, affect the geochemistry of these environments. If microbial communities are present in the sediments beneath the WAIS ice streams, they will have been isolated from outside environmental influences for a minimum of 20,000 years. This projectwill focus on the molecular characterization of microbes in a unique sediment core collected from beneath Ice Stream C, WAIS (WAISC) with two main hypotheses: 1) There is a unique microbial community present in the WAISC sediments, and 2) The WAISC sediment microbial community is active at near in situ conditions. The WAISC sediment microbes will be compared to microbes from other subglacial and marine sedimentary systems and microbes with geochemically-relevant metabolic activitie will be isolated. Work will be coordinated with other laboratories for pore water chemistry and sediment physical parameters to define this unique habitat. Resulting data should provide insight into microbial population dynamics and survival mechanisms in this cold, dark, and isolated environment. Furthermore, this study will expand our knowledge of microbial community structure and function to include Antarctic subglacial environments and may provide insights into possible roles of microbes during extreme "Snowball Earth" events and astrobiology. This project will support the training of a postdoctoral scholar and an undergraduate student in an interdisciplinary research project. The PI will use concepts from this project in both an introductory undergraduate course and a graduate level course. Data, images, and other materials will be made available through a publicly available web site.