How the function of carbon sequestration in boreal forests changes by permafrost table subside and re-rising process after forest fire

(USA side)

International Arctic Research Center, University of Alaska, Fairbanks.

(Canadian side)

Wood Buffalo National Park, Parks Canada

Aurora Research Institute, Northwest Territories, Canada

(Japan side)

Niigata University

Shinshu University

FY 2022-2024 Grant-in-Aid for Scientific Research (KAKENHI)

MATSUURA, Yojiro

Permafrost exists under ca. 70 percent of boreal forest region. Most of former researches were performed within permafrost-free boreal forests. Recent years, frequent large forest fires in boreal region reduce not only biomass storage in forests but affect stand structure of regenerated forests due to permafrost table subside and re-rising process. That basic knowledge of specific in permafrost-affected forests is necessary to predict carbon storage of boreal forests under changing climate.

We clarify the forest regeneration process with measurements of biomass accumulation, stand structure, and permafrost table depth. We also clarify the inflection point with growth shifting events and speculate the trajectory of carbon sequestration function.

We set up a couple of intensive research sites in Caribou-Poker Creek Research Watershed and Poker Flat Research Range, near Fairbanks, Interior Alaska. Additional sites will be set up in Wood Buffalo National Park, NWT, Canada. Permafrost condition of these two regions are different. Stand ages of those research sites vary from 4-year to ca. 100-yr after fires. Biomass accumulation, T/R ratio, permafrost depth will be measured. Stress-affected tree growth stage will be detected using stable isotope measurements.