Biogeochemistry and ecohydrology of northern peatlands

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Canada, along with 196 other parties, committed at the United National Framework Convention of Climate Change (UNFCC) Paris' 21st Conference of Parties (COP 21) to limit greenhouse gas emissions (GHGs) to levels that would achieve no more than 2oC increase from pre-industrial global temperature. This means the increase in GHGs in the atmosphere cannot exceed ~450 to 500 ppm CO2 equivalents 2016 is the first year that CO2 concentrations will exceeded 400 ppm! Unlike most of the other parties to COP 21, Canada contains a disproportionate amount of the world's terrestrial carbon in its living vegetation and soils. This has huge implications for how we manage our carbon landscape it makes no sense to reduce fossil fuel emissions to have them only replaced by emissions from land-use change or inadvertent biospheric feedbacks. My research program focusses on the highest density carbon ecosystem in Canada and the world peatlands. Northern peatlands cover ~ 6% of the world's land area (~12% of Canada), contain somewhere between 500 and 700 Gt C (150 Gt C in Canadian peatlands), and annually emit 40 to 50 Tg of methane (10% of global emissions and > 20% of natural sources). Yet our outstanding of peatlands and how they might respond to environmental change is much poorer than almost all other major ecosystems. This is troubling as peatlands have been identified as ecosystems that, if disturbed, could be contribute to tipping points in the Earth System. Peatlands are unique because their structure and function is strongly regulated by hydrological feedbacks. Hence, they are complex ecosystems they show a range of resilience to changes in external stressors but can change catastrophically beyond their limits of stability. My research program's objectives are to understand the complexity of peatlands so we can project the sensitivity to environmental change. My short-term objectives are to further explore the feedbacks between the hydrology and ecosystem processes and patterns across scales because they are an emergent property of peatland's stability; to examine how nutrients whose input is increasing due to long range transport and land-use change, along with climate change, influence their carbon cycle and carbon exchanges with the atmosphere; and to improve our ability to simulate peatlands biogeochemical processes. I will attain my objectives through a combination of empirical and theoretical studies and apply the advances in knowledge to improving our ability to project the consequences of future environmental change on peatlands, and the consequences of changes in peatlands on the earth system. Through this research program I will train several undergraduates, a M.Sc. and five PhDs in the interdisciplinary biogeosciences of biogeochemistry and ecohydrology. They will learn to become independent scientists preparing them for research careers in the academia, government and/or the private sector.