The Influence of Time since Fire & Repeated Fire on Organic Carbon Storage


Fernanda Santos and Amy Breen visited burned and unburned areas at the Kougarok fire site to evaluate the impact of wildfires on soil carbon storage.


Between June 14 and 21, 2022, NGEE Arctic scientists visited the Kougarok fire site near Nome, Alaska. One of the objectives of the fieldwork was to test whether soil carbon storage in the carbon-rich organic horizon of tussock tundra is affected by time since the last fire and repeated fires. To accomplish this, the thickness of the active layer and organic horizon was measured in unburned sites and sites that had burned once (one site in 1971 and another in 2002), twice (i.e., one site in 2002 and 2019), three times (one site in 1971, 2022, and 2019), and four times (one site in 1971, 1997, 2002, and 2015). Information on organic horizons was also collected at those sites. Samples were brought to Oak Ridge National Laboratory for elemental organic carbon analysis and quantification of carbon stocks. The results reported from this study will generate data on the amount of organic matter stored tussock tundra that can serve as fuel for fire and provide critical data needed on the influence of wildfires on carbon stored in tundra ecosystem. 

Fernanda Santos, Oak Ridge National Laboratory, 

Project Phase(s)