Impacts of Talik Microbial Geochemistry on a Changing Permafrost Landscape

Talik 微生物地球化学对不断变化的永久冻土景观的影响

• 批准号: RGPIN-2021-04348
• 负责人: Omelon, Christopher
• 金额: $ 1.82万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=742898
• 关键词: Impacts; Talik; Microbial; Geochemistry; Changing

The proposed research program takes an interdisciplinary approach to investigate the hydrology, geochemistry, and microbiology of taliks under lakes and ponds, defined as a layer or body of unfrozen ground in permafrost regions. These taliks are hydrologically connected to surface waters but are poorly understood due to long periods of extensive ice cover and inherent difficulty in accessing them. While permafrost creates an effective barrier that can isolate microbial communities within taliks, climate warming in the Arctic at twice the global mean is contributing to decreases in both the distribution and thickness of permafrost that will diminish these barriers and lead to talik expansion, which is of great concern when considering the microbial respiration of vast reserves of soil organic carbon in permafrost and associated methane release from thermokarst lakes. The Arctic is also experiencing dramatic hydrological and hydrogeological changes leading to a rapidly evolving interrelationship between surface waters and groundwaters. This is affecting the partitioning of water stored above and below ground and connectivity of surface waters with subsurface environments due to changing hydrologic flowpaths, and physicochemical conditions. These climate-related impacts will strongly influence talik environments, but the degree and extent of these impacts on microbial diversity and biogeochemistry and their subsequent future interconnectivity with surface waters are unknown. HQP-led projects will generate new knowledge about the extent and composition of taliks under lakes and ponds at three field sites in continuous and discontinuous permafrost regions. It will identify and map these taliks and their interconnectedness with other subsurface feature, measure and compare the thermal, hydrogeochemical, and microbial properties of these taliks, and determine how talik properties influence adjacent aqueous and sedimentary environments such as overlying waters or nearshore settings. HQP will conduct extensive fieldwork at these sites and become proficient in techniques in geophysics, geochemistry, metagenomics, and microscopy. In addition to new knowledge generated through the scientific work of 19 HQP, this program will directly benefit northern communities that are concerned about the impacts of climate warming on freshwater environments. In addition, Canadian citizens will directly benefit by having a better understanding of the Arctic terrestrial landscape through these efforts. Their knowledge will help society understand how climate warming is impacting the Arctic and will guide present and future policymakers in their determination for how Canada addresses global climate change. Finally, through the development of HQP-led projects that include 5 northern community members, this work will help to empower these communities to understand and prepare for future hydrological and geochemical changes as a result of climate warming.

拟议的研究计划采取跨学科的方法来调查湖泊和池塘下的taliks的水文学，地球化学和微生物学，定义为永久冻土区未冻结地面的层或体。这些水库在水文上与地表沃茨相连，但由于长时间的大面积冰层覆盖和进入这些水域的固有困难，人们对它们的了解很少。虽然永久冻土形成了一个有效的屏障，可以隔离talik内的微生物群落，但北极的气候变暖是全球平均水平的两倍，这有助于永久冻土的分布和厚度减少，这将减少这些屏障并导致talik扩张，当考虑到永久冻土中大量土壤有机碳储量的微生物呼吸作用和相关的甲烷释放时，热喀斯特湖泊北极地区还正在经历巨大的水文和水文地质变化，导致地表水和地下水之间的相互关系迅速变化。沃茨和地下水之间的相互关系迅速变化。沃茨。由于水文流动路径和物理化学条件的变化，这影响了储存在地上和地下的水的分配以及地表沃茨与地下环境的连通性。这些与气候有关的影响将强烈影响talik环境，但这些影响对微生物多样性和生物地球化学的程度和范围及其随后与地表沃茨的未来相互联系尚不清楚。HQP领导的项目将产生新的知识，在连续和不连续的永久冻土区的三个现场的湖泊和池塘下的talks的范围和组成。它将识别和绘制这些talik及其与其他地下特征的相互联系，测量和比较这些talik的热，水文地球化学和微生物特性，并确定talik特性如何影响邻近的水和沉积环境，如覆盖沃茨或近岸环境。HQP将在这些地点进行广泛的实地考察，并精通生物物理学，地球化学，宏基因组学和显微镜技术。除了通过19名HQP的科学工作产生的新知识外，该计划还将直接使关注气候变暖对淡水环境影响的北方社区受益。此外，加拿大公民将通过这些努力更好地了解北极陆地景观而直接受益。他们的知识将帮助社会了解气候变暖如何影响北极，并将指导现在和未来的政策制定者决定加拿大如何应对全球气候变化。最后，通过制定由HQP牵头的项目，其中包括5个北方社区成员，这项工作将有助于增强这些社区的能力，使其能够了解气候变暖导致的未来水文和地球化学变化，并为此做好准备。