Investigating microbial carbon transformations in the ultramafic biosphere and carbon fluxes through serpentine spring portals

研究超镁铁质生物圈中的微生物碳转化和通过蛇纹泉入口的碳通量

• 批准号: RGPIN-2015-06047
• 负责人: Morrill, Penny
• 金额: $ 1.97万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613907
• 关键词: Investigating; microbial; carbon; transformations; ultramafic

The 2014 IPCC report states with high confidence that “Total anthropogenic GHG emissions have continued to increase over 1970 to 2010 with larger absolute decadal increases toward the end of this period”. One proposed method of climate change mitigation is to sequester the carbon dioxide (CO2) in the ultramafic subsurface. However, the biogeochemical carbon cycling and the deep biosphere in the ultramafic subsurface are poorly understood. For example, this CO2 storage method may result in the production of methane (CH4) another powerful greenhouse gas. Pure research in tracing the carbon substrates, transformations, and products in this ultramafic system is required. My ongoing research program contributes to this need with long-term goals of 1) determining biogeochemical processing of carbon in the deep ultramafic biosphere and 2) determining carbon source and flux through portals that connect the deep biosphere and the atmosphere. Funds are requested to study the microbial processes in the high pH (>11) groundwaters associated with serpentinization - a set of reactions between water and ultramafic rock. My 1st set of research questions ask what do the microbes eat, what do they produce, and how do they survive in the ultramafic subsurface. My 2nd set of research questions ask, how do these systems exchange carbon with the atmosphere and what are the mechanisms that form the CH4 that is released from these systems. Canada will benefit from this research through the production of 10 highly qualified personnel - 2 PhD, 3 MSc, and 5 Undergraduate theses. Canadians will also benefit from the advancement in knowledge into carbon substrates, microbial transformations, and inorganic and organic carbon exchanges with the surface, as well as new biological discoveries in how life survives and thrives in high pH (>11) environments. These results could have a huge impact on how we view carbon transformations between short-term and long-term carbon cycles. For example, the use of carbonate rock as a carbon source by Serpentinomonas, a microbe recently discovered to be adapted to the high pH of serpentinized groundwater. This carbon transformation could have large implications on our understanding of the global carbon cycle, because this organism can move carbon out of the long-term carbon cycle to the short-term carbon cycle. Quantifying the flux of powerful greenhouse gases, CH4 and CO2, in and out of portals between the atmosphere and the deep biosphere must be considered, especially since the deep biosphere may house the majority of biomass on the planet and if CO2 sequestration is deployed in these systems.

2014年IPCC报告非常有信心地指出，“从1970年到2010年，人为温室气体排放总量继续增加，在这一时期结束时，绝对十年增长幅度更大”。减缓气候变化的一个拟议方法是将二氧化碳（CO2）封存在超镁铁质地下。然而，地球化学碳循环和超镁铁质地下深部生物圈的了解甚少。例如，这种二氧化碳储存方法可能会导致甲烷（CH 4）的产生，这是另一种强大的温室气体。在这个超镁铁质系统中，需要对碳基质、转化和产物进行纯研究。我正在进行的研究计划有助于这一需求的长期目标1）确定碳在深超镁铁质生物圈和2）确定碳源和通量通过连接深生物圈和大气的门户。要求提供资金，以研究与蛇纹化有关的高pH值（>11）地下水中的微生物过程-蛇纹化是水与超镁铁岩之间的一系列反应。我的第一组研究问题是微生物吃什么，它们生产什么，以及它们如何在超镁铁质地下生存。我的第二组研究问题是，这些系统如何与大气交换碳，以及形成这些系统释放的CH 4的机制是什么。加拿大将受益于这项研究，通过生产10个高素质的人员- 2博士，3硕士，和5个本科论文。加拿大人还将受益于碳基质、微生物转化、无机和有机碳与地表交换的知识进步，以及关于生命如何在高pH值（>11）环境中生存和繁荣的新生物学发现。这些结果可能会对我们如何看待短期和长期碳循环之间的碳转化产生巨大影响。例如，使用碳酸盐岩作为蛇形单胞菌（Serpentinomonas）的碳源，这是一种最近发现的适应蛇形地下水高pH值的微生物。这种碳转化可能对我们对全球碳循环的理解产生重大影响，因为这种生物可以将碳从长期碳循环转移到短期碳循环。必须考虑对大气层和深层生物圈之间的入口和出口的强大温室气体甲烷和二氧化碳的流量进行量化，特别是因为深层生物圈可能容纳地球上的大部分生物质，如果在这些系统中部署二氧化碳固存。