Collaborative Research: Microbial Ecology of Ocean Basement Aquifers: ODP Borehole Observatories

合作研究：海洋基底含水层微生物生态学：ODP 钻孔观测站

• 批准号: 0604203
• 负责人: Jan Amend
• 金额: $ 10万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0604203&HistoricalAwards=false
• 关键词: Collaborative; Research; Microbial; Ecology; Ocean

The ocean crust consists of basement rock formed at the mid-ocean ridges (MOR) plus the overlying sediments that accumulate over time as the basement rock ages and moves away from the MORs. There is growing evidence that a substantial biosphere exists throughout the immense volume of aging, sediment-buried basement underlying the global system of MOR flanks and ocean basins. The current project will exploit the unprecedented opportunities provided by long-term Ocean Drilling Program borehole observatories (CORKs) to collect uncontaminated samples of basement fluids for geochemical, microbiological and ecological characterization. Because water-rock reactions and associated microbial habitats vary with basement temperature and age, the geochemistry and molecular (genetic) diversity will be examined in basement fluids from multiple borehole observatories on the flanks of the Juan de Fuca Ridge (JFR), ranging in basement age (ca.1.24 to 3.5 million years) and in basement temperature (38 to 65degrees centigrade). The synergy between water-rock and aqueous (e.g., oxidation-reduction) reactions and the organisms living in proximity to them demands an interdisciplinary approach to research. In this project, the microbial community and metabolic diversity will be studied in close conjunction with geochemical processes. In situ, real-time analyses will simultaneously measure key dissolved reduction-oxidation (redox) species; such measurements will help to elucidate the metabolic climate of the basement fluids (e.g., how the microbes gain energy and fix carbon) and guide culturing portions of this study. These geochemical and biological studies will provide input data for thermodynamic calculations of numerous potential metabolic reactions (e.g., a sort of energy 'road map'), which will provide a 'reality-check' for the occurrence of certain metabolisms. Geochemical measurements and energetic calculations will provide a much-needed environmental context for realistic modeling of microbial community synergy. The principal investigators and students from the participating institutions will interact closely with hydrogeologists, geochemists and technologists from numerous other institutions, as well as with staff of the International Ocean Drilling Program (IDOP) to both exploit existing CORK observatories and to influence development of new borehole observatories that are optimal for ocean basement microbial community studies. Multiple undergraduate, graduate and post-doctoral students will be intimately involved in all stages of the project, and will benefit from cross-institutional informal education and training. The project will actively interact with UH's NASA Astrobiology Institute (NAI), for which subseafloor biosphere studies is an increasingly significant component. Students and PIs will participate in educational outreach projects to K-12 schools and the general public, especially including continuation of the very successful ship-to-classroom and "Teacher at Sea" outreach programs; the latter will involve integrating K-12 science teachers directly into all aspects of the project from initial planning to field and laboratory work.

洋壳由形成于大洋中脊（莫尔）的基底岩石加上随着基底岩石年龄增长和远离MOR而积累的上覆沉积物组成。 越来越多的证据表明，在莫尔侧翼和海洋盆地的全球系统之下，在大量老化的沉积物掩埋的基底中存在着大量的生物圈。 目前的项目将利用长期大洋钻探计划钻孔观测站提供的前所未有的机会，收集未受污染的基底流体样品，用于地球化学、微生物和生态特征分析。由于水岩反应和相关的微生物栖息地随基底温度和年龄而变化，因此将在胡安德富卡脊（JFR）两侧的多个钻孔观测站的基底流体中检查地球化学和分子（遗传）多样性，基底年龄（约124至350万年）和基底温度（38至65摄氏度）。 水岩和水岩之间的协同作用（例如，氧化-还原）反应和生活在它们附近的生物体需要跨学科的研究方法。在本项目中，微生物群落和代谢多样性将与地球化学过程密切结合进行研究。原位实时分析将同时测量关键的溶解还原-氧化（氧化还原）物质;这种测量将有助于阐明基底流体的代谢气候（例如，微生物如何获得能量和固定碳）并指导本研究的培养部分。这些地球化学和生物学研究将为许多潜在代谢反应的热力学计算提供输入数据（例如，一种能量“路线图”），这将为某些新陈代谢的发生提供“现实检查”。地球化学测量和能量计算将为微生物群落协同作用的现实建模提供急需的环境背景。来自参与机构的主要研究人员和学生将与来自许多其他机构的水文地质学家，地球化学家和技术专家以及国际大洋钻探计划（IDOP）的工作人员密切互动，以利用现有的CORK观测站，并影响新的钻孔观测站的发展，这些观测站是海洋基底微生物群落研究的最佳选择。 多名本科生、研究生和博士后学生将密切参与该项目的各个阶段，并将受益于跨机构的非正式教育和培训。该项目将积极与UH的NASA天体生物学研究所（NAI）互动，其中海底生物圈研究是一个越来越重要的组成部分。学生和PI将参与教育推广项目，以K-12学校和公众，特别是包括非常成功的船到教室和“海上教师”推广计划的延续;后者将涉及将K-12科学教师直接融入项目的各个方面，从最初的规划到实地和实验室工作。