Linking microbial community composition, metabolic functions and ecology in terrestrial subsurface and surface habitats

将陆地地下和地表栖息地的微生物群落组成、代谢功能和生态联系起来

• 批准号: RGPIN-2019-06670
• 负责人: Lazar, Cassandre
• 金额: $ 2.19万
• 依托单位: Université du Québec à Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=716242
• 关键词: Linking; microbial; community; composition; metabolic

The terrestrial subsurface lies beneath our feet in the landmasses of continents and islands. These underground habitats contain a major portion of the microorganisms on Earth, who participate in the cycling and storage of key elements such as carbon, nitrogen or phosphorus, particularly in aquifer ecosystems. These aquifers, which provide most of our drinking water, are composed of groundwater flowing through layers of saturated and unsaturated rocks. Thus, subsurface microorganisms can be found either in a free-living planktonic state in the water, or in a sessile state attached to solid surfaces. Understanding the essential biogeochemical processes occurring in the subsurface is based on investigations of community composition and activities of microbial populations inhabiting these environments. Because aquifers are sustained by water seeping from the surface, they show various degrees of connectivity to the surface and are vulnerable to changes in surface conditions. However, links between surface and subsurface microbial ecology have rarely been addressed, and will be a central axis in this research program. The long-term objective of this research program is to understand the microbial ecology and functioning of subsurface environments by studying them as open systems with links to and from surface aquatic ecosystems. The short-term objectives are to 1) establish the succession in planktonic microbial community composition and associated functional capacities that develop between surface recharge areas, subsurface groundwaters, and surface discharge regions; 2) determine the composition and metabolic activities of the groundwater planktonic communities and the environmental factors influencing this microbial activity; and 3) identify the composition, abundance and metabolic characteristics of the microbiota living on rock surfaces. To address these objectives, we will apply a combination of state-of-the-art omics and culture-based approaches, based on three distinct aquifer systems in Quebec. Application of these cutting-edge methods, and collaborations with other researchers (e.g. working on aquatic habitats, hydrogeologists), will allow training of highly qualified graduate students. The proposed research will expand our knowledge on the origin of microorganisms in subsurface aquifer systems, and on the metabolic activities employed by these microbes to survive in the challenging fluctuating conditions encountered in the subsurface. Our original approach of studying the subsurface as an open system will provide key insights into the elusive overall composition of subsurface microbial populations. This approach will allow bringing together researchers working on surface and subsurface microbial ecology. These findings will be crucial in predicting responses of these habitats to surface perturbations.

地表下的陆地位于我们脚下的大陆和岛屿的陆块中。这些地下生境包含地球上大部分微生物，它们参与碳、氮或磷等关键元素的循环和储存，特别是在含水层生态系统中。这些含水层提供了我们大部分的饮用水，由流经饱和和非饱和岩石层的地下水组成。因此，地下微生物可以在水中以自由生活的浮游状态存在，或者以附着于固体表面的固着状态存在。了解地下发生的基本生物地球化学过程是基于对这些环境中微生物群落组成和活动的调查。由于含水层靠地表渗出的水维持，它们与地表的连通程度各不相同，容易受到地表条件变化的影响。然而，表面和地下微生物生态学之间的联系很少得到解决，将是本研究计划的中心轴线。 该研究计划的长期目标是通过研究与地表水生生态系统有联系的开放系统来了解地下环境的微生物生态学和功能。短期目标是：1）确定地表补给区、地下水和地表排泄区之间的浮游微生物群落组成和相关功能能力的演替; 2）确定地下水浮游微生物群落的组成和代谢活动以及影响这种微生物活动的环境因素;以及3）鉴定生活在岩石表面的微生物群的组成、丰度和代谢特征。 为了实现这些目标，我们将采用最先进的组学和文化为基础的方法相结合，在魁北克三个不同的含水层系统的基础上。这些尖端方法的应用，以及与其他研究人员的合作（例如从事水生栖息地，水文地质学家），将允许高素质的研究生的培训。拟议的研究将扩大我们对地下含水层系统中微生物起源的了解，以及这些微生物在地下遇到的具有挑战性的波动条件下生存的代谢活动。我们最初的研究地下作为一个开放的系统的方法将提供关键的见解难以捉摸的地下微生物种群的整体组成。这种方法将允许汇集研究表面和地下微生物生态学的研究人员。这些研究结果将是至关重要的，在预测这些生境的表面扰动的反应。