Canadian Forest Service Publications

Fire regime zonation under current and future climate over eastern Canada. 2013. Boulanger, Y.; Gauthier, S.; Gray, D.R.; Le Goff, H.; Lefort, P.; Morissette, J. Ecol. Appl. 23:904-923.

Year: 2013

Issued by: Laurentian Forestry Centre

Catalog ID: 34717

Language: English

Availability: PDF (request by e-mail)

Mark record

Abstract

Fire is a major disturbance in Canadian forests. Along with fuel and ignition characteristics, climatic conditions are seen as one of the main drivers of fire regimes. Projected changes in climate are expected to significantly influence fire regimes in Canada. As fire regime greatly shapes large-scale patterns in biodiversity, carbon, and vegetation, as well as forest and fire management strategies, it becomes necessary to define regions where current and future fire regimes are homogeneous. Random Forests (RF) modeling was used to relate fire regime attributes prevailing between 1961 and 1990 in eastern Canada with climatic/fire-weather and environmental variables. Using climatic normals outputs from the Canadian Regional Climate Model (CRCM), we delineated current (1961–1990) and future (2011–2040, 2040–2070, 2071–2100) homogeneous fire regime (HFR) zones. Heterogeneous response of fire regime to climate changes is projected for eastern Canada with some areas (e.g., western Quebec) experiencing very small alterations while others (e.g., southeastern Ontario) are facing great shifts. Overall, models predicted a 2.2- and 2.4-fold increase in the number of fires and the annual area burned respectively mostly as a result of an increase in extreme fire-weather normals and mean drought code. As extreme fire danger would occur later in the fire season on average, the fire season would shift slightly later (5–20 days) in the summer for much of the study area while remaining relatively stable elsewhere. Although fire regime values would change significantly over time, most zone boundaries would remain relatively stable. The information resulting from HFR zonations is clearly of interest for forest and fire management agencies as it reveals zones with peculiar fire regimes that would have been hidden otherwise using predefined administrative or ecological stratifications.

Plain Language Summary

A fire regime can be characterized by area burned, and the severity, recurrence and abundance of fires within a given territory. Different fire regimes exist in Eastern Canada. Researchers sought to determine if climate change will have an effect on fire regimes.

To this end, they developed a prediction model using the Canadian database for fire regimes. This model uses fire regimes during the period from 1961 to 1990 as a reference. Using variables relating to climate, topography, vegetation and human presence within the territory, the researchers projected how fire regimes could develop from now to 2100.

They found that there will be little change in the delineation of fire regime zones, but that the fire regimes themselves will vary greatly within these zones.

According to the model, between now and the end of the 21st century the area burned and the number of fires will more than double compared with the reference period, in Ontario, northern Quebec and southern New Brunswick. This will affect the commercial forest zone and a segment of non-commercial forests further north. Also, the majority of fires will occur slightly later in the season.