Biodiversity and vertical segmentation of microbial communities and gene expression in cold ocean ecosystems

冷海在全球碳通量中发挥着重要作用，是加拿大周围海洋环境的主要类型。这些水域通常被认为是不稳定的，表层混合良好，浮游生物群落同质，多样性低。微生物包括来自所有主要生命分支的代表：细菌、古生菌和真核生物。这三个区域相互作用，在任何给定的水域中形成复杂的食物网。微生物食物网支持依赖北冰洋的所有较大生物，并负责全球范围内的生物地球化学循环。大多数自由生活的微生物从未被培养过，我们才开始通过应用分子生物学技术来调查海洋来了解群落结构的复杂性。我们的工作重点是确定北冰洋微生物和几种关键酶的多样性和丰富性。最近的报告表明，微生物多样性比之前认为的要大10到1000倍，我们的数据证实了北冰洋不同区域和周围海域不同深度的不同复杂群落。由于全球变暖，北极目前面临着冰盖消失的威胁，这正在影响影响微生物物种分布的循环模式。我们的目标是确定哪些物种和生物地球化学途径可能在变化的北极中占据主导地位，为下游建模和管理提供关键信息。

Cold oceans play a major role in global carbon fluxes and are the dominant type of marine environments around Canada. These waters were typically thought of as unstable with well-mixed surface layers and homogeneous, low-diversity plankton communities. Microbes include representatives from all major branches of life: Bacteria, Archaea and Eukaryota. These three domains interact to form complex food webs in any given parcel of water. Microbial food webs support all larger organisms dependent on Arctic Seas and are responsible for biogeochemical cycling on a global scale. The majority of free living microbes have never been cultured, we have only begun to understand the complexity of community structure by applying molecular biological techniques to investigate the ocean. Our work focuses on identifying the diversity and abundance of microbes and several key enzymes in Arctic Seas. Recent reports suggests that microbial diversity is 10 to 1000 times greater than previously thought and our data has confirmed diverse complex communities at different depths over different regions of the Arctic Ocean and surrounding seas. The Arctic is currently threatened with loss of ice cover due to global warming, which is impacting circulation patterns that influence microbial species distributions. Our objective is determine what species and biogeochemical pathways are likely to dominate in a changing arctic, providing key information for downstream modelling and management.