Title: Permafrost degradation stimulates carbon loss from experimentally warmed tundra
Author: Natali, S.M.; Schuur, E.A.G.; Webb, E.; Hicks Pries, C.E.; Crummer, K.G.;
Source: Ecology and Society
Publication Series: Scientific Journal (JRNL)
Description: A large pool of organic carbon (C) has been accumulating in the Arctic for thousands of years because cold and waterlogged conditions have protected soil organic material from microbial decomposition. As the climate warms this vast and frozen C pool is at risk of being thawed, decomposed, and released to the atmosphere as greenhouse gasses. At the same time, some C losses may be offset by warming-mediated increases in plant productivity. Plant and microbial responses to warming ultimately determine net C exchange from ecosystems, but the timing and magnitude of these responses remain uncertain. Here we show that experimental warming and permafrost (ground that remains below 08C for two or more consecutive years) degradation led to a two-fold increase in net ecosystem C uptake during the growing season. However, warming also enhanced winter respiration, which entirely offset growing-season C gains. Winter C losses may be even higher in response to actual climate warming than to our experimental manipulations, and, in that scenario, could be expected to more than double overall net C losses from tundra to the atmosphere. Our results highlight the importance of winter processes in determining whether tundra acts as a C source or sink, and demonstrate the potential magnitude of C release from the permafrost zone that might be expected in a warmer climate.
Keywords: Arctic tundra, carbon, climate change, Eight Mile Lake, Alaska, USA, net ecosystem exchange, permafrost.
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
XML: View XML
Natali, S.M.; Schuur, E.A.G. ; Webb, E. ; Hicks Pries, C.E. ; Crummer, K.G. 2014. Permafrost degradation stimulates carbon loss from experimentally warmed tundra. Ecology and Society. 95(3): 602-608.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility