A field-based experimental system for the evaluation of the effects of elevated temperature and CO2 on peatlands

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A field-based experimental system for the evaluation of the effects of elevated temperature and carbon dioxide on peatlands is proposed. In two different boreal peatland types (poor and intermediate fens) with ~10 years of historical climatological and hydrological monitoring data, we will install a system that comprises 16 clear polycarbonate open-top chambers, a carbon dioxide delivery system, a ground-heating system, and an off-grid power system. With this, we will implement a full factorial treatment of climate change factors, including elevated carbon dioxide, and soil warming, to simulate future climate and soil conditions. Clear polycarbonate chambers (~1m dia x 1m high) with a 0.2m deep rigid collar will contain each experimental treatment. In each of the experimental chambers, a ground-heating system will be installed to simulate the effects of prolonged atmospheric warming on the surface peats. Precision flow-controllers and a high-pressure carbon dioxide source will be used to increase carbon dioxide concentration in experimental chambers to 1000 ppm carbon dioxide to simulate future atmospheric concentrations. This globally unique infrastructure will facilitate the research of six principal investigators and their research groups asking fundamental questions about the effects of a changing climate on peatland ecosystems. A main goal of all investigators is to reduce the scientific uncertainty surrounding the fate of stored carbon in boreal peatlands, and the potential for carbon release back to the atmosphere, amplifying future climate change. This feedback has profound implications for ecosystem and climate modeling, as well as for national economic well-being in a future 'carbon economy'. In addition, the infrastructure will allow the researchers to deepen our understanding of the cycling of nitrogen, biodiversity and ecosystem function, below-ground microbial biogeochemical processes, and the physics of heat and moisture transfer in peatlands, all of which couple to the carbon cycle. All of this data will be used directly to improve models that will be used to forecast the trajectory of Canada's peatland carbon stores.