Microorganisms in a Changing Climate: community response and effect on biogeochemical cycling

点击翻译按钮获取中文摘要

My research program focuses on the microbial ecology of permafrost in polar environments, examining how microbial activity and dormancy relate to diversity, evolution and biogeochemical cycling on Earth. I employ a variety of in situ and laboratory tools, combining molecular sequencing with microbial physiology and activity assays. While less than 1% of known microorganisms can be cultivated in the lab and thus are known to us solely through molecular analyses, this approach results in a more holistic understanding of microbial ecology than genomic analyses alone. A comprehensive understanding of how microbial diversity, activity, adaptation, and dormancy affect biogeochemical cycling is increasingly relevant in the face of climate change, where microbial communities in thawing permafrost are making the shift from dormancy to activity. Permafrost contains the world's largest reservoir of carbon (C), and accounts for 34% of the world's coasts. Warming can accelerate the microbial degradation of stored permafrost C, resulting in the release of the GHGs (eg.CO2, CH4). This release can result in a feedback leading to accelerated climate change, but the magnitude and timing of GHG emissions and their impact on climate change remain uncertain. Measuring the quantities and fate of degrading permafrost C, and on what timescales it is processed terrestrially and in nearshore environments is crucial to understanding how C flux (GHG emissions) will impact climate change in the future. Microorganisms are the drivers of such biogeochemical cycling, and thus the microbial diversity, metabolic activity, and potential for adaptation in response to changing climate are a critical piece of missing data.  The long-term objectives of my research program are to contribute to knowledge of the microbial mechanisms responsible for biochemical cycling in polar environments undergoing change. Towards this vision, my short-term objectives investigate permafrost systems currently experiencing (or poised to experience) rapidly changing conditions:  1. Determine the microbial activity and inhabitants driving GHG flux in eroding coastal permafrost.  2. Determine microbial cell state in thawing permafrost and assess if these states may evolve over time.  3. Determine if dry permafrost globally is prohibitive to active microbial life, or if that is limited to the only dry permafrost region studied to date.  The proposed program will train 3-5 HQP per year in polar microbiology, molecular techniques, bioinformatics, GHG measurements, conducting field work in the North, and cutting-edge techniques such as single cell genomic sequencing. Through international collaborators, this innovative program will facilitate HQP access to state-of-the-art instrumentation not yet available in Canada (eg. single cell sorting, NanoSIMS).  HQP will be poised for a broad range of careers nationally and internationally in northern research, microbiology and biotechnology, among others.