Investigating the role of soil microbial processes in aquatic greenhouse gas emissions in Eastern Canadian permafrost landscapes

研究土壤微生物过程在加拿大东部永久冻土景观水生温室气体排放中的作用

• 批准号: 560895-2020
• 负责人: Douglas, Peter
• 金额: $ 2.19万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=706993
• 关键词: Investigating; role; soil; microbial; processes

Greenhouse gas (GHG) emissions from thawing permafrost represent a major potential positive feedback to global warming, but our understanding of the biological, geochemical, and hydrological mechanisms controlling these emissions remains limited. Recent research points to aquatic environments (lakes and ponds) as hotspots of GHG emissions, but the pathways through which permafrost soil carbon contributes to aquatic GHG emissions remain unclear. Currently there is a lack of research integrating microbiological, biogeochemical, and hydrological processes in soils and aquatic environments in permafrost landscapes, which this interdisciplinary project aims to address. We will study these processes in ecosystems in Eastern Canada representing both continuous and discontinuous permafrost. Our FRQNT-funded research project focuses on (1) characterizing relationships between microbial communities, organic matter (OM), and GHG fluxes across soil to aquatic environmental gradients through field sampling and (2) identifying the mechanisms controlling linkages between microbial communities and GHG fluxes using incubation experiments. Our team comprises strong expertise in carbon cycle biogeochemistry (Peter Douglas- McGill), Arctic aquatic ecology (Isabelle Laurion-INRS), soil microbiology (Cynthia Kallenbach- McGill), microbial genomics (Jérôme Comte- INRS), and nutrient biogeochemistry (Roxane Maranger- Université de Montréal). New funding from the NSERC NOVA program will facilitate collaboration with a hydrologist (Melissa Lafrenière-Queens), broadening the research program to focus on specific mechanisms of hydrological transport of organic matter, microbes, and nutrients from soils to ponds. This will include examination of the role of summer rainfall and different size classes of organic matter in controlling soil-pond carbon fluxes. It will also facilitate a comparative analysis of rapidly eroding gullies with permafrost thaw ponds in terms of their potential for mobilizing permafrost carbon reservoirs. This new funding study will provide key insights into mechanistic linkages between soil microbiology, hydrology, and permafrost GHG emissions.

温室气体（GHG）的排放从融化的冻土代表了一个主要的潜在的积极反馈，全球变暖，但我们的了解控制这些排放的生物，地球化学和水文机制仍然有限。最近的研究指出，水生环境（湖泊和池塘）的温室气体排放的热点，但通过永久冻土土壤碳有助于水生温室气体排放的途径仍然不清楚。目前，缺乏研究整合微生物，生物地球化学和水文过程中的土壤和水环境中的永久冻土景观，这一跨学科的项目旨在解决。我们将研究这些过程中的生态系统在加拿大东部代表连续和不连续的永久冻土。我们的FRQNT资助的研究项目的重点是（1）通过实地采样表征微生物群落，有机质（OM）和温室气体通量之间的关系，通过土壤到水环境梯度和（2）确定控制微生物群落和温室气体通量之间的联系的机制使用孵育实验。我们的团队包括碳循环地球化学（Peter道格拉斯-麦吉尔），北极水生生态学（Isabelle Laurion-INRS），土壤微生物学（Cynthia Kallenbach-麦吉尔），微生物基因组学（Jérôme Comte- INRS）和营养物地球化学（Roxane Maranger-蒙特利尔大学）的强大专业知识。NSERC NOVA计划的新资金将促进与水文学家（Melissa Lafrenière-Queens）的合作，扩大研究计划，重点关注有机物，微生物和营养物质从土壤到池塘的水文运输的具体机制。这将包括检查夏季降雨和不同大小的有机物在控制土壤池塘碳通量的作用。 它还将有助于比较分析快速侵蚀的冲沟和永久冻土解冻池在调动永久冻土碳库方面的潜力。这项新的资助研究将为土壤微生物学，水文学和永久冻土温室气体排放之间的机械联系提供关键见解。