Climate control of aquatic microbial ecosystems

水生微生物生态系统的气候控制

• 批准号: RGPIN-2019-04195
• 负责人: Vincent, Warwick
• 金额: $ 6.87万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745035
• 关键词: Climate; control; aquatic; microbial; ecosystems

Global climate projections (including those presented in the 2018 IPCC Special Report) indicate that the greatest warming effects of greenhouse gas accumulation in the atmosphere will be at high northern latitudes, and consistent with these projections, the Arctic is warming at rates 2-3 times faster than the global mean. Our NSERC Discovery program is focused on aquatic ecosystems in the changing northern environment, specifically the interactions between physical aspects such as temperature, ice cover, light and mixing, and the structure and activity of microscopic communities that underpin the food webs in high-latitude lakes and rivers. Lakes and rivers are major features of northern landscapes that in many areas are now experiencing massive change as a result of permafrost thaw and erosion. We will investigate aquatic ecosystems at the southern margin of permafrost to examine how subarctic lakes and rivers respond to ongoing landscape thaw and associated organic carbon mobilisation, with emphasis on the production of greenhouse gases (methane and carbon dioxide) and microbial community structure. Additionally, by way of isolations and culture experiments, we will evaluate the hypotheses that thaw lakes contain distinct cyanobacterial communities that are responsive to warming and that include toxic species. We will build on our limnological studies and related climate observations based out of Ward Hunt Island near the northern limit of Canada (lat. 83.1°N). Our ongoing research at this site for >15 years means that we have been present to observe extreme events and abrupt changes in ecosystem processes, and can place our studies each summer in a longer term interannual context. This work will include high-resolution observations of oxygen dynamics in a coastal lake to test the hypothesis that ecosystem metabolism is controlled by summer snow and ice conditions, in turn linked to changes in Arctic Ocean sea ice. Thick biofilm communities (microbial mats) coat the base of many lake, pond and stream ecosystems in the polar regions, and recent observations suggest that they acquire carbon and energy in more diverse ways than previously thought. We aim to apply a suite of physiological and molecular approaches in experiments to determine the functional organization of mat communities and their responses to temperature and winter darkness. The information will improve our ability to monitor, understand and predict the responses of these ecosystems to ongoing climate change. Our research directly addresses Canada's environmental needs and responsibilities in polar research and reporting, and the results are likely to continue to attract wide public, policy maker and scientific interest. The work has been entirely formulated as research training projects, resulting in advanced expertise in aquatic microbiology, ecosystem science and climate change studies to meet the growing employment opportunities in these sectors.

全球气候预测（包括2018年IPCC特别报告中提出的预测）表明，大气中温室气体积累的最大变暖效应将出现在北方高纬度地区，与这些预测一致，北极的变暖速度比全球平均速度快2-3倍。我们的NSERC发现计划专注于变化的北方环境中的水生生态系统，特别是温度，冰盖，光照和混合等物理方面之间的相互作用，以及支撑高纬度湖泊和河流食物网的微观群落的结构和活动。 湖泊和河流是北方景观的主要特征，在许多地区，由于永久冻土的融化和侵蚀，这些景观正在经历巨大的变化。我们将调查永久冻土南缘的水生生态系统，研究亚北极湖泊和河流如何应对持续的景观解冻和相关的有机碳动员，重点是温室气体（甲烷和二氧化碳）的产生和微生物群落结构。此外，通过隔离和培养实验，我们将评估的假设，解冻湖包含不同的蓝藻群落，对变暖的反应，包括有毒物种。我们将建立在我们的湖沼学研究和相关的气候观测的基础上，基于沃德亨特岛附近的加拿大北方限制（lat。北纬83.1度）。我们在该地点进行了超过15年的研究，这意味着我们一直在观察极端事件和生态系统过程的突然变化，并且可以将我们的研究放在更长期的年际背景下。这项工作将包括对一个沿海湖泊的氧气动态进行高分辨率观测，以检验生态系统新陈代谢受夏季冰雪条件控制的假设，而夏季冰雪条件又与北冰洋海冰的变化有关。厚厚的生物膜群落（微生物垫）覆盖着极地地区许多湖泊，池塘和溪流生态系统的基础，最近的观察表明，它们以比以前认为的更多样化的方式获得碳和能量。我们的目标是在实验中应用一套生理和分子方法来确定垫社区的功能组织及其对温度和冬季黑暗的反应。这些信息将提高我们监测、理解和预测这些生态系统对持续气候变化的反应的能力。 我们的研究直接解决了加拿大在极地研究和报告中的环境需求和责任，其结果可能会继续吸引广大公众，政策制定者和科学界的兴趣。这项工作完全是作为研究培训项目制定的，在水生微生物学、生态系统科学和气候变化研究方面积累了先进的专门知识，以满足这些部门日益增长的就业机会。