Effects of Wildfire
Fire is a dominant driver of carbon balance in the boreal forest, and the model can follow its aftermath.
Biome BGC reliably simulates observed changes in leaf area, net primary production, and carbon stocks for a boreal forest wildfire chronosequence, as well as for natural and harvested cold temperate forests. That capability is what makes the model useful for following a stand from the year of a fire toward the mature forest that may eventually replace it.
A fire removes vegetation and litter carbon and resets the stand structure. Leaf area index drops sharply, shortwave radiation is no longer intercepted by a full canopy, and net primary production falls. Over the following decades, the ecosystem slowly rebuilds leaf area and soil organic matter. Because the same model also carries the water cycle and the carbon and nitrogen cycles, the recovery can be examined in all three at once.
What the model tracks after fire
- Leaf area index as the canopy regrows from the disturbance.
- Net primary production as radiation capture recovers.
- Carbon stocks in vegetation, litter, and soil as succession proceeds.
- Water and nitrogen fluxes that constrain the pace of recovery.
The study by Bond Lamberty and colleagues describing fire as the dominant driver of central Canadian boreal forest carbon balance is listed on the model publications page. Broader context on fire and disturbance in forest carbon cycles appears in the Carbon Blog.