Collaborative Research: Biogeochemistry and Geomicrobiology of Taylor Glacier Basal Ice

摘要这项研究将解决冰冻圈生物学中一个新出现的令人兴奋的问题：微生物是否能够在冰川冰中代谢？拟议的研究将通过实地测量和实验室实验相结合的方式，对泰勒冰川（南极洲麦克默多干谷）基底冰的地球化学和地球微生物学进行全面评估。我们的整体方法将提供数据，将营养物质的可用性，地球化学成分和气体成分与基底冰序列中的微生物细胞密度，多样性和代谢状态联系起来。对同一冰相进行多样本分析将有助于评估基底冰中的化学和微生物联系，以及微生物原位改变气体成分的方式。拟议的方法将解决国家研究理事会的“基因组时代的极地生物学前沿”（2003年）概述的两个关键问题：（一）“微生物在这种（冷冻）环境中能否繁殖？“和（ii）“在不同的零度以下环境中微生物之间有什么相似之处和不同之处？“证明微生物活动在-17摄氏度的冰川冰中原位发生，将代表冰冻圈生物学的重大进步，并显着扩大生物圈的已知边界。这些信息与冰芯古气候社区高度相关，因为它将为一些冰芯气体记录的不一致性提供可行的解释。极地冰川的基底冰区与火星北方冰帽边缘区的分层沉积物有相似之处。因此，我们的研究也将对有关火星冰中微生物持久性和生存的讨论产生影响。本研究将支持2名新研究者，并为2名博士提供培训。学生和2名本科生。来自科学和工程领域无人代表社区的学生将被积极招募担任这些职位。基于网络的工具，以目标学生有兴趣追求科学事业将保持和扩大后，将我们的结果纳入NSF资助（DERMEED-1）在密歇根州立大学正在建设的图书馆，作为国家（SMETE）数字图书馆的一部分。

AbstractThe 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.