Molecular and genomic insights into the microbial ecology of hypoxic marine ecosystems

加拿大是一个海洋国家，对地球海洋的生态健康具有重大的经济和社会利益。在很大程度上，海洋的生态是由微生物控制的。微生物构成了海洋生物多样性和生物量的大部分，在维持较大生命形式的存在方面发挥着核心的生物地球化学作用。目前，由于人为因素，包括气候变化和过量的养分输入，海洋正在发生根本性的变化。这些变化的一个重要结果是海洋生态系统中缺氧的增加。缺氧限制了动物的分布，导致了所谓的“死亡地带”，而生态系统的形成几乎完全由微生物物种组成。与死区相关的微生物群落在组成和代谢能力方面是独特的，并且可能通过产生温室气体和有毒的硫化氢来加剧缺氧对环境的影响。考虑到海洋缺氧的生态影响，以及微生物过程对氧敏感生物地球化学循环的贡献，进一步了解缺氧系统的微生物生态学具有重要意义。为此，研究目标是对缺氧系统进行长期、高频的时间序列分析，这将产生新的基于分子和基因组的微生物群落组成和活性描述。系统生物学方法将用于识别和跟踪与加拿大沿海水域缺氧加剧相关的微生物群落组成和活动的变化。这些信息将对微生物群落在导致海洋缺氧的物理和生物地球化学过程中的作用和反应的预测模型的后期发展至关重要。这项工作将通过揭示以前未被认识到的与海洋条件相关的微生物多样性和代谢模式，为微生物生态学和海洋学领域提供独特的新见解，这些模式可能在未来几年因人类活动而扩大。

Canada is a maritime nation with major economic and social interests in the ecological health of Earth's oceans. In large part, the ecology of the ocean is governed by microbial life. Microorganisms constitute the majority of biodiversity and biomass in oceans and play central biogeochemical roles that sustain the existence of larger life forms. Currently, the oceans are undergoing fundamental alterations due to anthropogenic factors, including climate change and excess nutrient inputs. One significant outcome of these alterations is an increase in oxygen-deficiency (hypoxia) in marine ecosystems. Hypoxia restricts animal distribution, leading to so-called "dead zones," and the formation of ecosystems comprised almost exclusively of microbial species. Microbial communities associated with dead zones are unique in composition and metabolic capabilities, and may exacerbate the environmental impact of hypoxia through production of green house gases and toxic hydrogen sulfide. Given the ecological impact of marine hypoxia, and the contribution of microbial processes to oxygen-sensitive biogeochemical cycles, it is important to further understand the microbial ecology of hypoxic systems. To this end, the research objective is to perform long term, high frequency time-series analysis of hypoxic systems that will generate novel molecular and genomic-based descriptions of microbial community composition and activity. Systems biology approaches will be used to identify and track changes in microbial community composition and activity associated with intensification of oxygen depletion in coastal Canadian waters. This information will be essential in the later development of predictive models of microbial community role and response in the physical and biogeochemical processes that result in marine hypoxia. This work will provide exceptional novel insight in the fields of microbial ecology and oceanography by revealing previously unrecognized patterns in microbial diversity and metabolism associated with ocean conditions that are likely to expand in coming years due to human activity.