Does ground water affect how severe fires are in our peatlands? And does that fire severity affect the length of time it takes for bryophytes to regenerate? These are the two questions we seek to answer.
Previous studies have found peatlands to be critical for global carbon storage (Glaser, 1987), but when peat is dry it is also a good fuel for wildfires (Rein, 2013), releasing carbon into the atmosphere (Kettridge et al., 2015). It is for these reasons that we want to explore 1) if decreases in groundwater level in peatland will increase fire severity, and 2) if increases fire severity will decrease bryophyte regeneration. Our second objective is aimed to determine peatland's ability to recover from more severe fires.
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Data was collected from peatlands in the Northwest Territories and in Alberta 1, 2, and 5 years post a fire event. At each site 12 plots were measured, 6 were hummocks and 6 were hollows. The three variables that were measured in each plot were water table levels, depth of burn, and bryophyte regeneration. Depth of burn was measured as a proxy for fire severity, where deeper burn depths imply greater fire severities.
Through a preliminary analysis of boxplots and scatterplots, we have found no strong or consistent relationships for either of our objectives. For objective one, water table depths ranging from 0 to -60 cm did not appear to influence depth of burn. Therefore, the extraction of groundwater by industries near these peatlands is not likely to significantly increase local fire risks. For objective two, our measure of fire severity, depth of burn, did not have any consistent relationships with bryophyte cover. Therefore, the choice of fire managers to let severe peatland fires burn would likely not have long-term impacts on bryophyte regeneration. More exploration of these questions is needed to fully understand and inform fire managers on our confidence of these conclusions.
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