Fuel and climate controls on peatland fire severity

Abstract

A series of experimental fires were conducted to investigate the effect of ground-fuel structure and fuel moisture content in controlling fire severity in a Calluna vulgaris dominated environment. Their influence on fire-induced temperature pulses into the soil (peat) was quantified. The effect of fire-related changes in fuel structure on peat microclimate was also examined. We found the moss and litter (M/L) layer to be important in insulating peat from fire-induced temperature pulses, especially at the peat surface. We recorded higher fire-induced peat temperatures and residence times in microplots where a drought had been simulated, with climatic conditions playing a key role. The removal of the heather canopy due to burning and the change in structure of the M/L layer were found to similarly increase both peat daily temperature fluctuation and peat mean temperature.