The proposed research will address an emerging and exciting question in cryospheric biology: are microorganisms capable of metabolism in glacier ice? The proposed study will involve a comprehensive assessment of the biogeochemistry and geomicrobiology of Taylor Glacier (McMurdo Dry Valleys, Antarctica) basal ice via a combination of field measurements and laboratory experiments. Our holistic approach will provide data to connect nutrient availability, geochemical composition, and gas composition with microbial cell density, diversity and metabolic status in the basal ice sequence. Multi-sample analysis of the same ice facies will allow assessment of the chemical and microbial linkages in basal ice and the manner by which microbes may modify gas compositions in situ. The proposed approach will address two key questions outlined by the National Research Council's "Frontiers in Polar Biology in the Genomic Era" (2003): (i) "Can microorganisms in this (frozen) environment reproduce?" and (ii) "What are the similarities and differences among microorganisms in different subzero environments?" Confirming that microbial activity occurs in situ in glacier ice at temperatures of -17C would represent a significant advance in cryospheric biology and significantly expand the known boundaries of the biosphere. Such information is highly relevant to the ice core paleoclimatic community, as it would provide a viable explanation for inconsistencies in some ice-core gas records. The basal ice zones of polar glaciers show similarities with the layered deposits evident in images of the marginal zones of the northern ice cap on Mars. Thus, our research will also have implications relevant to discussions about microbial persistence and survival in ice on Mars. This research will support 2 new investigators, and provide training for 2 Ph.D. students and 2 undergraduate students. Students from unrepresented communities in science and engineering will be actively recruited for these positions. Web-based tools to target students interested in pursuing a career in science will be maintained and expanded upon by incorporating our results into the NSF funded (DERMEED-1) library under construction at MSU, as part of the national (SMETE) digital library.
