Forecasting wildfire-induced declines in potential forest harvest levels across Québec

Abstract

Wildfires are increasing in importance in many regions of the Canadian boreal forest and are an ongoing risk for forest management activities. We simulated the effects of fires on long-term harvest levels on the 59 forest management units of the province of Québec, Canada, for the 2020-2100 period. Different climate change pathways (stable, RCP 4.5 or 8.5) and salvage logging rates (20% or 70% of mature burned stands) were simulated. Changes in forest flammability due to climate change, species migration and forest management were also considered. Under stable climatic conditions, the decline in potential harvest levels due to fire, based on 50 simulations per scenario, ranged between 3 - 36% (mean = 12%) when high salvage logging rates were simulated, compared to 4 - 59% (mean = 21%) for low salvage rates. Climate change caused increases in burn rates between -3 and 39% for RCP 4.5, and between 33 and 69% for RCP 8.5 at the end of the 21st century. However, the effects of these modified burn rates on harvest levels did not differ substantially from those of baseline burn rates, probably because the projected burn rates were comparatively greater during the later part of the simulations (2070-2100), when their impacts on harvest rate calculations were limited. This study indicates that potential harvest levels calculated without considering wildfires are likely to be non-sustainable.

Under what circumstances can the forest sector contribute to 2050 climate change mitigation targets? A study from forest ecosystems to landfill methane emissions for the province of Quebec, Canada

“…Yet, uncertainty regarding the net carbon sink potential of mature and old‐growth stands should not overshadow their role as carbon reservoirs (Harel et al, 2021). On the other hand, expected changes in natural disturbance regimes could negatively impact the productivity and regeneration capacity of forest ecosystems (Boulanger et al, 2017) and thus jeopardize the sustainability of wood production (Bouchard et al, 2022; Boucher et al, 2018; Brecka et al, 2020). Changes in natural disturbance regimes could become a major issue beyond the period covered by our study (2018–2050) and result in additional future uncertainty.…”

Assessing Spatial Patterns of Burn Severity for Guiding Post-Fire Salvage Logging in Boreal Forests of Eastern Canada

“…In the eastern Canadian boreal forest, the proportion of salvage logging in burned forests is generally less than 20% of total annual burned areas and never exceeds more than 50% for individual fires (see for ex. ; Bouchard et al, 2023;Leduc et al, 2015;. This is mostly due to three additive constraints: the abundance of mature forests in the pre-fire landscape, the rapid loss of wood economic value due to wood-boring insects (Gervais et al, 2012) and the absence of a pre-existing road network in many boreal forest landscapes.…”