Collaborative Research: Geobiology of high pH springs in the Philippines - probing the deep biosphere

部分a.技术说明居住在地球上的微生物群落？地球的地下是一个科学上未知的领域。可居住的地下可能穿透地球？地壳深度为5？10公里，取决于地热梯度。 据估计，最近深地下栖息地可以容纳更多的生物量和生物多样性比地球上？s表面。然而，我们对碳循环、氮循环或任何其他发生在地下生物圈中的地球化学循环以及这些循环如何影响地表过程知之甚少。该项目将调查菲律宾蛇绿岩地区发现的高pH值流体中的这些过程，在那里，活跃的Sepentinization使H2和CH4与地层流体接触，为地下生物圈提供能量。这项拟议的研究将提供菲律宾两个蛇绿岩地区（赞巴莱和巴拉望）一套高pH值蛇纹化泉的基线地球化学数据。在一个为期两年的重点研究计划中，我们将阐明高pH值，深源流体中的微生物地球化学循环，并将微生物的作用直接与微生物地球化学过程联系起来。我们的三个平行研究链涉及（1）深层来源的蛇绿岩衍生流体是否为化能无机营养微生物群落提供了可居住的小生境，这些微生物群落可以通过系统的地球化学来预测，（2）基于核酸的分析和培养方法反映了功能性遗传能力，证实了预测的代谢策略，和（3）由于菲律宾高pH值流体中的CO2和碳酸氢盐含量较低，化学异养代谢和/或甲烷氧化菌在这些地下流体中主导于替代的化学自养代谢。该项目还包括对研究生和本科生进行实地、实验室和分析方法方面的有意指导，以及开发一个基于标本和网络的混合学习模块，将实地调查结果与大学和高中一级的科学教育举措联系起来，特别是考虑到地球科学素养举措的目标（网址：科学和社会更广泛的影响包括支持早期地球和其他行星体上的生命，因为有人提出蛇纹化（超镁铁质岩石的水蚀变，产生双原子氢，可能还有复杂的有机分子）可以为原始生态系统提供关键的能量和碳。这些过程可能会继续支持生命在？极端？现代地球的地下环境。蛇绿岩地区也是研究蛇纹岩长期碳储存的可能性的研究人员非常感兴趣，作为CO2的地质储存库。 由于次生矿物学类似于混凝土，蛇绿岩也作为潜在的放射性废物存放地而受到关注。 考虑到这些不同的影响，有必要更好地了解蛇绿岩流体中的地球化学循环概念，以了解这些应用的潜在影响。对项目的非技术性解释？的更广泛的意义和重要性微生物群落栖息在地球上？地球的地下是一个科学上未知的领域，可能会穿透地球？直到它太热而无法生存。据估计，最近深地下栖息地可以容纳更多的生物量和生物多样性比地球上？这一巨大的生物量储存库对地球上生物化学循环的影响是我们目前对地球系统的认识中的一个巨大漏洞。该项目将调查生命如何改变菲律宾两个地方（赞巴莱和巴拉望）高pH值泉水中的水和岩石，并使我们能够更多地了解关键的化学和生物联系，这些联系可能有助于科学（特别是在这些令人兴奋的环境中定义生物圈的未知边缘？包括微生物如何在低氧、低营养环境中生存）和社会（与正在进行的碳封存、有毒废物储存、采矿废物生物修复和微型医疗应用方面的实验有密切联系）。迈耶-董巴德博士Cardace博士的研究重点是陆地和浅海底热液系统的地球生物学，Cardace博士研究了构造边缘的地球生物学，并在海底和沿海环境中进行了实地研究。在这个合作研究项目中，他们打算了解地球如何与生命一起进化，从而影响碳和其他元素的储存。他们带来了对导师和研究培训的承诺，这里授予的资金将使更多的学生获得技能，包括定量推理，分析研究和科学写作，材料和研究结果将通过学校访问和互动，数据丰富的在线模块与在职教师和学生迅速分享。

Part A. Technical description Microbial communities inhabiting the Earth?s subsurface occupy a scientifically uncharted realm. The habitable subsurface may penetrate the Earth?s crust to depths of 5?10 km, depending on geothermal gradients. It has been estimated recently that the deep subsurface habitat could accommodate more biomass and biodiversity than on Earth?s surface. Yet, we know little about carbon cycling, nitrogen cycling, or any other biogeochemical cycling that takes place in this subsurface biosphere or how these may impact surface processes. This project will investigate these processes in high pH fluids found in ophiolite regions of the Philippines, where active sepentinization brings H2 and CH4 in contact with formation fluids, energizing the subsurface biosphere.This proposed research will deliver baseline biogeochemical data for a suite of high pH serpentinizing springs in two Philippines ophiolite localities (Zambales and Palawan). In a focused two-year research plan, we will elucidate biogeochemical cycling in high pH, deeply sourced fluids in our Philippines field locations, and tie the role of microorganisms directly to biogeochemical processes. Our three parallel research strands involve whether (1) deeply sourced, ophiolite-derived fluids afford habitable niches for chemolithotrophic microbial communities that can be predicted by the geochemistry of the system, (2) nucleic acid based analyses and culturing approaches reflect functional genetic competence that confirms the predicted metabolic strategies, and (3) chemoheterotrophic metabolisms and/or methanotrophs dominate over alternative chemoautotrophic metabolisms in these subsurface fluids, due to low CO2 and bicarbonate in the Philippine high pH fluids. This project also comprises intentional mentorship of graduate and undergraduate students in field, laboratory, and analytical methods, and the development of a blended specimen- and web-based learning module tying together field findings with science education initiatives at the collegiate and high school levels, particularly with the Earth Science Literacy Initiative goals in mind (http://www.earthscienceliteracy.org.Scientific and societal broader impacts include support for life on the Early Earth and other planetary bodies, as it has been proposed that serpentinization (the aqueous alteration of ultramafic rocks, yielding diatomic hydrogen, and possibly complex organic molecules) can provide critical energy, and carbon to primitive ecosystems. These processes likely continue to support life in ?extreme? subsurface settings on the modern Earth. Ophiolite regions are also of great interest to researchers investigating the possibilities of long term carbon storage in serpentinites, as geological repositories of CO2. Because secondary mineralogy resembles concrete, ophiolites are also gaining attention as potential radioactive waste depositories. With these diverse impacts in mind, a better concept of biogeochemical cycling in ophiolite-hosted fluids is necessary to understand potential impacts for these applications.Part B. Non-technical explanation of the project?s broader significance and importanceMicrobial communities inhabiting the Earth?s subsurface occupy a scientifically uncharted realm, and may penetrate the Earth?s crust to depths of 5 to 10 km--until it is too hot to survive. It has been estimated recently that the deep subsurface habitat could accommodate more biomass and biodiversity than on Earth?s surface, and the impact of this vast reservoir of biomass on biogeochemical cycling on Earth is a gaping hole in our current knowledge of Earth systems. This project will investigate how life transforms water and rock in high pH springs at two localities in the Philippines, at Zambales and Palawan, and allow us to learn more about critical chemical and biological connections in ways that may serve both science (particularly in defining the unknown edge of the biosphere in these exciting settings?including how microbes survive in low oxygen, low nutrient settings) and society (with strong links to ongoing experiments in carbon sequestration, toxic waste storage, bioremediation of mining wastes, and micro-scale medical applications). Dr. Meyer-Dombard?s research focus has been the geobiology of terrestrial and shallow submarine hydrothermal systems, and Dr. Cardace has studied the geobiology of tectonic margins, with field localities in the seabed and coastal settings. Together in this collaborative research project, they intend to learn how Earth is evolving in concert with life in ways that impact reservoirs of carbon and other elements. They bring a commitment to mentorship and training in research to the table also, and the funds granted here will allow more students to gain skills including quantitative reasoning, analytical research, and science writing, and materials and findings will be rapidly shared with in service teachers and their students through school visits and interactive, data-rich on-line modules.