Collaborative Research: Biogeochemistry and Geomicrobiology of Taylor Glacier Basal Ice

摘要提出的研究将解决冰冻圈生物学中一个新兴的和令人兴奋的问题：微生物能够在冰川冰中代谢吗？拟议的研究将包括通过实地测量和实验室实验相结合，对泰勒冰川（南极洲麦克默多干谷）基冰的生物地球化学和地球微生物学进行综合评估。我们的整体方法将提供数据，将营养物质有效性、地球化学组成和气体组成与基冰序列中的微生物细胞密度、多样性和代谢状态联系起来。对相同冰相的多样本分析将有助于评估基冰中的化学和微生物联系，以及微生物可能改变原地气体成分的方式。拟议的方法将解决国家研究委员会在“基因组时代的极地生物学前沿”（2003）中概述的两个关键问题：(1)“微生物能在这种（冷冻）环境中繁殖吗？”(2)“不同零度以下环境中的微生物有什么异同？”确认微生物活动在零下17摄氏度的冰川冰中就地发生，将代表冰冻圈生物学的重大进展，并显著扩展生物圈的已知边界。这些信息与冰芯古气候群落高度相关，因为它将为某些冰芯气体记录的不一致提供可行的解释。极地冰川的基底冰带与火星北部冰盖边缘区域的图像中明显的分层沉积物相似。因此，我们的研究也将对火星冰中微生物的持久性和生存的讨论产生影响。本研究将支持2名新研究员，培养2名博士生和2名本科生。来自未被代表的科学和工程社区的学生将积极招聘这些职位。针对有兴趣从事科学事业的学生的基于网络的工具将被维护和扩展，并将我们的研究结果纳入正在密歇根州立大学建设的国家科学基金会资助的（dermed -1）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.