Decadal vegetation changes in a northern peatland, greenhouse gas fluxes and net radiative forcing.
2006 (English)In: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 12, no 12, 2352-2369 p.Article in journal (Refereed) Published
Thawing permafrost in the sub-Arctic has implications for the physical stability and biological dynamics of peatland ecosystems. This study provides an analysis of how permafrost thawing and subsequent vegetation changes in a sub-Arctic Swedish mire have changed the net exchange of greenhouse gases, carbon dioxide (CO<sub>2</sub>) and CH<sub>4</sub> over the past three decades. Images of the mire (ca. 17 ha) and surroundings taken with film sensitive in the visible and the near infrared portion of the spectrum, [i.e. colour infrared (CIR) aerial photographs from 1970 and 2000] were used. The results show that during this period the area covered by hummock vegetation decreased by more than 11% and became replaced by wet-growing plant communities. The overall net uptake of C in the vegetation and the release of C by heterotrophic respiration might have increased resulting in increases in both the growing season atmospheric CO<sub>2</sub> sink function with about 16% and the CH<sub>4</sub> emissions with 22%. Calculating the flux as CO<sub>2</sub> equivalents show that the mire in 2000 has a 47% greater radiative forcing on the atmosphere using a 100-year time horizon. Northern peatlands in areas with thawing sporadic or discontinuous permafrost are likely to act as larger greenhouse gas sources over the growing season today than a few decades ago because of increased CH<sub>4</sub> emissions.
Place, publisher, year, edition, pages
2006. Vol. 12, no 12, 2352-2369 p.
IdentifiersURN: urn:nbn:se:su:diva-33990DOI: 10.1111/j.1365-2486.2006.01267.xOAI: oai:DiVA.org:su-33990DiVA: diva2:283929