Forested peatlands and changing fire regimes: implications for peat resources and fire management

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Peatlands cover c. 170 million hectares of Canada's land surface and these extensive peat reserves make Canada one of the world's leaders in industrial peat resource extraction, use and export. However, northern peatlands are likely to become increasingly vulnerable to wildfire as climate change lowers water tables and exposes deeper peat to burning. Recent research in western Canada has shown that fire activity already plays an important role in peatland carbon cycling and regional fire emissions. Yet there continues to be uncertainty as to whether peatlands across Canada's boreal zone are vulnerable to burning, and whether the greater surface soil moisture deficits predicted for this region with climate change will increase the frequency and/or severity of peat fires. If fire activity increases, fire suppression costs likely will rise dramatically (Canada spends an average of $500 million a year on direct suppression costs). Additionally, fire management agencies operate with a narrow margin between success and failure, a disproportionate number of fires may escape initial attack under a warmer climate, resulting in an increase in area burned much greater than the corresponding increase in fire weather severity. Peat fires currently are problematic for fire management, as the occurrence and duration of smouldering consumption that dominates the burning of the peat resource is poorly understood. Additional information on peatland vulnerability and ecological consequences to wildfire is critical to both the peat resource and fire management communities. We will develop new quantitative fire danger and smoldering potential models for peatland fires that will guide environmental policy. We also will examine several ecological processes (peat accumulation, water balance, biodiversity) that are sensitive indicators of ecosystem health in these important ecosystems. Given that the smouldering of deep peat layers serves as a draw-down on firefighting resources and is likely to involve negative ecosystem and human health consequences, the development of these predictive tools will aid as a decision tool for fire and peat resource management and in the future could lead to public health warnings in advance of dangerous air quality linked to fire emissions.