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.

永久冻土融化产生的温室气体（GHG）排放是对全球变暖的一个主要潜在正反馈，但我们对控制这些排放的生物、地球化学和水文机制的了解仍然有限。最近的研究指出水生环境（湖泊和池塘）是温室气体排放的热点，但永久冻土土壤碳导致水生温室气体排放的途径仍不清楚。目前，缺乏将永久冻土景观土壤和水生环境中的微生物、生物地球化学和水文过程整合起来的研究，而这个跨学科项目旨在解决这一问题。我们将研究加拿大东部代表连续和不连续永久冻土的生态系统中的这些过程。我们的 FRQNT 资助的研究项目侧重于 (1) 通过现场采样表征微生物群落、有机物 (OM) 和从土壤到水生环境梯度的温室气体通量之间的关系，以及 (2) 通过孵化实验确定控制微生物群落和温室气体通量之间联系的机制。我们的团队拥有碳循环生物地球化学（Peter Douglas- McGill）、北极水生生态学（Isabelle Laurion-INRS）、土壤微生物学（Cynthia Kallenbach- McGill）、微生物基因组学（Jérôme Comte- INRS）和营养物生物地球化学（Roxane Maranger- Université de）等方面的丰富专业知识。 蒙特利尔）。 NSERC NOVA 项目的新资金将促进与水文学家（Melissa Lafrenière-Queens）的合作，扩大研究项目，重点关注有机物、微生物和养分从土壤到池塘的水文输送的具体机制。这将包括检查夏季降雨和不同大小类别的有机质在控制土壤-池塘碳通量中的作用。 它还将有助于对快速侵蚀的沟壑与永久冻土融化池进行比较分析，以了解其调动永久冻土碳库的潜力。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制联系提供重要见解。