Grant: Discovery Grants Program - Individual

Although only accounting for ~3% of the Earth's land surface, peatlands store about 30% of global soil carbon (C) and are a globally significant source of methane (CH4). Indeed, natural northern peatlands currently have low or neutral nitrous oxide (N2O) emission, but under climate change and increased nutrient (e.g. nitrogen (N) and phosphorus (P)) levels, will have the potential to become a hotspot of N2O emission. Still, how northern peatlands will function in terms of C sink and greenhouse gas (GHG) emissions with climate warming and increased nutrients is unclear. This significantly increases the uncertainty of Canada achieving net-zero emission by 2050. My research program will help address this question and reduce the uncertainties. The long-term objective of my research program aims to use empirical observation and process-based ecosystem modeling to examine how northern peatlands will function their C cycling and GHG emissions under climate change and human disturbances. Specifically, this NSERC-DG will employ field experiment and process-based peatland modeling to address the following objectives : examine how C cycling, GHG emissions and water use efficiency (WUE) in northern peatlands change under warming and N and P fertilization; investigate how microbial and vegetation composition changes in northern peatlands under warming and N and P fertilization; study how C cycling, GHG emissions and WUE in northern peatlands respond to the interactions of warming and reduced N addition level and how they are regulated by vegetation composition changes; determine how microbial compositions and Sphagnum coverage change in northern peatlands with different vegetation composition under warming and reduced N addition level; explore how these changes and interactive responses can be parametrized in the McGill Wetland Model to simulate carbon dioxide and CH4 cycling in northern peatlands. My research program will be of great value to global change science, especially peatland C cycling science. Specifically, this research program will improve our understanding of how northern peatlands respond to climate warming, increased nutrient availability and vegetation composition changes. This improved understanding and data collected from my research program will help us parameterize and evaluate peatland CH4 cycling models with inclusion of vegetation and microbial dynamics. Moreover, the outcomes of my research program have potential to go beyond the role of peatlands in C cycling and GHG emissions and could potentially have far-reaching implications on climate change and peatland conservation policy. My research program attempts to provide sound scientific evidence for promoting peatland conservation, and help evaluate a potential role of peatlands under conditions of warmer and increased N P availability as a natural solution in Canada to achieving net-zero emission by 2050.