Authors: Xinyuan Wei*, University of Maine, Daniel Hayes, University of Maine, Shawn Fraver, University of Maine
Topics: Physical Geography, Canada, Earth Science
Keywords: Boreal forest, Canopy fire, Carbon recovery
Session Type: Paper
Start / End Time: 8:00 AM / 9:40 AM
Room: Napoleon B3, Sheraton 3rd Floor
Presentation File: No File Uploaded
Crown fire represents a dominant, stand-replacing disturbance in boreal forests. Modeling and inventory studies point to short fire cycles in this region, ranging from 40 to 140 years. As a result of these short cycles, fires significantly drive their carbon storage and fluxes through direct carbon release but also legacy effects of resetting succession. A better description of boreal forest carbon recovery patterns following crown fires, including gross primary productivity (GPP) and net primary productivity (NPP), is crucial to understand the overall forest carbon cycle. In this study, we used historical fire records, Landsat images, and land cover data in the period of 1950-2015 from Wood Buffalo National Park (WBNP), a 44,807 km2 area of boreal forest in Alberta and the Northwest Territories, Canada, to digitize individual canopy fire perimeters and obtain time-since-last-fire (TSLF) maps for the 2000 to 2015 time period. Satellite-based estimates of GPP and NPP modeled from MODIS data over this time period were normalized using Pseudo Invariant Features to eliminate anomalies introduced by climate change. By combining extracted post-fire GPP and NPP patterns with TSLF maps, we developed post-fire time-series dynamics in annual time steps for each burned area. Through this analysis, (1) we described the post-fire trajectories for GPP and NPP; (2) we explored the years required for GPP and NPP to recover to their before-fire status, and (3) by normalizing the GPP and NPP to the years having the highest and lowest growing season temperatures, we assessed the climate-warming influence on post-fire carbon recovery.