The impact of permafrost thaw on ecosystem carbon balance: net ecosystem exchange of a heterogenous landscape undergoing permafrost thaw

• Other Authors: EdwardSchuur
• Format: Dataset
• Language: unknown
• Published: Bonanza Creek LTERBoreal Ecology Cooperative Research Unit University of Alaska FairbanksP.O. Box 756780 FairbanksAK99775USA907-474-6364907-474-6251 2010
• Subjects: climate; eddy covariance; net ecosystem exchange; permafrost; carbon; landscape; Arctic; alaska range; Thermokarst; Tundra; Alaska
• Online Access: http://hdl.handle.net/10255/dryad.16342; http://metacat.lternet.edu/knb/metacat/knb-lter-bnz.447.4/xml

In this larger study, we are asking the question: Is old carbon that comprises the bulk of the soil organic matter pool released in response to thawing of permafrost? We are answering this question by using a combination of field and laboratory experiments to measure radiocarbon isotope ratios in soil organic matter, soil respiration, and dissolved organic carbon, in tundra ecosystems. The objective of these proposed measurements is to develop a mechanistic understanding of the SOM sources contributing to C losses following permafrost thawing. We are making these measurements at an established tundra field site near Healy, Alaska in the foothills of the Alaska Range. Field measurements center on a natural experiment where permafrost has been observed to warm and thaw over the past several decades. This area represents a gradient of sites each with a different degree of change due to permafrost thawing. As such, this area is unique for addressing questions at the time and spatial scales relevant for change in arctic ecosystems. Understanding how landscape level physical and biological changes effect carbon cycling is important for estimating the carbon balance of an ecosystem undergoing permafrost thaw.