Linking microbial ecology and biogeochemistry in the St. Lawrence Estuary through functional genomics.

通过功能基因组学将圣劳伦斯河口的微生物生态学和生物地球化学联系起来。

• 批准号: 420049-2012
• 负责人: Walsh, David
• 金额: $ 7.57万
• 依托单位: Concordia University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Ship Time
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=515821
• 关键词: Linking; microbial; ecology; biogeochemistry; St.

Coastal aquatic environments, such as the St. Lawrence Estuary (SLE) in Eastern Canada, are productive ecosystems that support diverse biological communities, including commercially important marine life. In many respects, these ecosystems are sustained by the activity of microorganisms. For example, microbes are involved in the production and transformation of organic matter (OM), which influences global carbon (C) and nitrogen (N) cycles and controls the flow of energy and nutrients through marine ecosystems. Presently, the chemistry of the oceans is changing at a global scale due to human activity, which can lead to ocean acidification and hypoxia both globally and locally in the SLE. Understanding the factors controlling theses processes in relation to the C and N cycles requires a characterization of the structure and function of different bacterial communities thriving throughout the water column and the sediments. Here, we seek financial support to build upon several years of foundational research with an overall objective of expanding our time series work on the linkages between microbial community dynamics and C and N transformations in the SLE. We will combine novel sampling techniques, with functional genomics, microbiological, as well as organic and inorganic geochemical methods to better constrain the links between bacterial diversity/dynamics, OM cycling and oxygen concentrations along the fresh-salt water transition in SLE. We will collect samples for taxonomic and genomic studies. Moreover, we are building on our previous work by including an experimental functional genomics component, where we will manipulate the C and nutrient availability and track microbial responses in order to further characterize the microbial groups and metabolic pathways that underlie C and N cycling in the estuary. Our sampling effort is modest but critical as it will allow collecting live material to look at present-day dynamics of bacterial diversity, activity and dynamics. This information is pivotal to our understanding of bacterial dynamics along the salinity and oxygen gradients, and on how bacteria are affected by and affect OM chemical composition, reactivity and recycling in coastal systems.

沿海水生环境，如加拿大东部的圣劳伦斯河口，是支持包括具有重要商业价值的海洋生物在内的各种生物群落的生产性生态系统。在许多方面，这些生态系统是由微生物的活动维持的。例如，微生物参与有机物的生产和转化，而有机物影响全球碳（C）和氮（N）循环，并控制海洋生态系统中能量和营养物质的流动。目前，由于人类活动，海洋的化学性质正在全球范围内发生变化，这可能导致全球和局部SLE的海洋酸化和缺氧。了解控制这些过程中的C和N循环的因素，需要在整个水柱和沉积物中茁壮成长的不同细菌群落的结构和功能的表征。在这里，我们寻求财政支持，以建立在几年的基础研究，扩大我们的时间序列工作的微生物群落动态和C和N之间的联系在SLE的转换的总体目标。我们将结合联合收割机新的采样技术，功能基因组学，微生物，以及有机和无机地球化学方法，以更好地限制细菌多样性/动态，OM循环和氧气浓度之间的联系沿着淡水-咸水转换在SLE。我们将收集样本用于分类学和基因组学研究。此外，我们正在建立在我们以前的工作，包括实验功能基因组学组件，在那里我们将操纵C和营养物质的可用性和跟踪微生物的反应，以进一步表征微生物组和代谢途径，在河口C和N循环的基础。我们的采样工作是适度的，但至关重要，因为它将允许收集活的材料，看看当今的细菌多样性，活性和动态的动态。这一信息是至关重要的，我们的细菌动力学的理解沿着盐度和氧气梯度，以及细菌是如何影响和影响OM的化学成分，反应性和回收沿海系统。