HR: 11:50h
AN: B42B-05    [Abstracts]
TI: West Siberian peatlands: A global methane source since the early Holocene
AU: * Smith, L C
EM: lsmith@geog.ucla.edu
AF: UCLA Dept. Geography, 1255 Bunche Hall, Box 951524, Los Angeles, CA 90095 United States
AU: MacDonald, G M
EM: macdonal@geog.ucla.edu
AF: UCLA Dept. Geography, 1255 Bunche Hall, Box 951524, Los Angeles, CA 90095 United States
AU: Velichko, A A
EM: paleo@glasnet.ru
AF: Russian Academy of Sciences, Institute of Geography, Moscow, 109017 Russian Federation
AU: Beilman, D W
EM: dbeilman@ucla.edu
AF: UCLA Dept. Geography, 1255 Bunche Hall, Box 951524, Los Angeles, CA 90095 United States
AU: Borisova, O K
EM: paleo@glasnet.ru
AF: Russian Academy of Sciences, Institute of Geography, Moscow, 109017 Russian Federation
AU: Frey, K E
EM: frey@ucla.edu
AF: UCLA Dept. Geography, 1255 Bunche Hall, Box 951524, Los Angeles, CA 90095 United States
AU: Kremenetski, K V
EM: costya@geog.ucla.edu
AF: UCLA Dept. Geography, 1255 Bunche Hall, Box 951524, Los Angeles, CA 90095 United States
AU: Sheng, Y
EM: sheng@geog.ucla.edu
AF: UCLA Dept. Geography, 1255 Bunche Hall, Box 951524, Los Angeles, CA 90095 United States
AB: Tropical wetlands are thought to have been a major driver of early Holocene fluctuations in atmospheric methane, in part because high-latitude peatlands were not extensively developed in North America by ~11 ka, a period of peak methane concentration. However, the timing of peatland expansion in Russia, which contains nearly half of the world's peat, is virtually unknown. We determine the age, spatial evolution, and carbon stock of the world's largest peatland complex, the West Siberian Lowland (WSL). Radiocarbon dates taken throughout the region reveal broad and rapid peatland expansion 11.5 - 9 ka, significantly pre-dating comparable development in North America. This same period coincides with peak atmospheric methane concentrations and high interpolar gradient as recorded in Greenland and Antarctic ice cores. GIS inventory of ~30,000 unpublished measurements, satellite imagery and field data finds that WSL carbon stocks are larger than previously thought (70.2 Pg), representing up to ~26% of all terrestrial carbon accumulated since the Last Glacial Maximum. No evidence for catastrophic oxidation is found, suggesting the region has behaved primarily as a net carbon sink and global source of atmospheric methane since the early Holocene.
UR: http://lena.sscnet.ucla.edu
DE: 1890 Wetlands
DE: 1600 GLOBAL CHANGE (New category)
DE: 1610 Atmosphere (0315, 0325)
DE: 1615 Biogeochemical processes (4805)
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting