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Area and Carbon Content of Sphagnum Since Last Glacial Maximum

DOI: 10.3334/CDIAC/vrc.001

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K. Gajewski, A. Viau, M. Sawada, D. Atkinson and S. Wilson
Laboratory for Paleoclimatology and Climatology, Department of Geography,
University of Ottawa,
165 Waller Street, Ottawa,
Ontario, K1N 6N5 Canada.

Period of Record

21000-0 years BP


The distribution and abundance of Sphagnum spores in North America and Eurasia are mapped for the past 21ka, as described in Gajewski et al. (2002). In summary, spore data were taken from existing pollen data bases, as were radiocarbon chronologies. The abundance of Sphagnum spores was mapped at 2000-year intervals beginning 21000 years BP (before present). The present-day distribution of abundant Sphagnum spores corresponds closely to areas with peatland development, with maximum Sphagnum abundance between 630 and 1300 mm annual precipitation and between -2° and 60°C mean annual air temperature. Carbon content of peatlands was generated from estimated peatland area, calculated values of peat thickness, and specified values of bulk density (112 × 103 g m-3) and fraction of carbon (51.7%).


During the Wisconsin glaciation, there were apparently not large areas of peatland in North America, except in Alaska. High Sphagnum spore percentages were found in eastern North America during deglaciation. Major peatland development occurred in boreal North America after 9000 years BP and there was a southward movement of high Sphagnum spore abundance after 5000 years BP in the western Great Lakes region. Major peatland development began after 9000 years BP in Europe and Asia. On the basis of maps of the area supporting peatlands, carbon accumulation in peatlands is estimated to be low prior to 11000 years BP, increased slightly between 11000 and 5000 years BP, and greatly increased during the past 5000 years. Global total area of 23 × 106 km2 was achieved at 1000 years BP, and total carbon has increased to the current value of 455 Pg (1 petagram = 1015 grams) of carbon.


  • Gajewski, K., A. Viau, M. Sawada, D. Atkinson and S. Wilson. 2001. Sphagnum peatland distribution in North America and Eurasia during the past 21,000 years. Global Biogeochemical Cycles 15:297-310.

CITE AS: Gajewski, K., A. Viau, M. Sawada, D. Atkinson and S. Wilson. 2002. Area and Carbon Content of Sphagnum Since Last Glacial Maximum. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. doi: 10.3334/CDIAC/vrc.001