Wildfire return intervals: impacts of diminishing fire return intervals on boreal peatlands using combined field/lidar approaches

Abstract

This thesis investigates the influence of increasing fire frequency on the soil characteristics, vegetation structural characteristics, and rate of growth, in peatlands in Single Burn, SB (2011 fire areas), and Double Burn, DB (1956 + 2011 fires) areas within the Boreal Plains Ecozones of Canada. Field data were acquired in July 2019 at the Utikuma Region Study Area (URSA) and were used in combination with a multi-temporal lidar dataset that spanned 17 years. Soil characteristics, such as bulk density, pH, and depth of burn were found to be significantly different in DBs than in SB areas. DB areas were found to have greater heights and greater rates of growth than SB Peatlands. Results suggest increasing shrub encroachment into peatlands under conditions of increased burning which has implications on the trajectory of peatland succession, and changes to fire fuels, which may impact future peatland resiliency.