Siberian Peatlands a Net Carbon Sink and Global Methane Source since the Early Holocene

L. C. Smith, University of California, Los Angeles
G. M. MacDonald, University of California, Los Angeles
A. A. Velichko, Russian Academy of Sciences
D. W. Beilman, University of California, Los Angeles
O. K. Borisova, Russian Academy of Sciences
K. E. Frey, University of California, Los Angeles
K. V. Kremenetski, University of California, Los Angeles
Y. Sheng, University of California, Los Angeles

Abstract

Interpolar methane gradient (IPG) data from ice cores suggest the "switching on" of a major Northern Hemisphere methane source in the early Holocene. Extensive data from Russia's West Siberian Lowland show (i) explosive, widespread peatland establishment between 11.5 and 9 thousand years ago, predating comparable development in North America and synchronous with increased atmospheric methane concentrations and IPGs, (ii) larger carbon stocks than previously thought (70.2 Petagrams, up to ∼26% of all terrestrial carbon accumulated since the Last Glacial Maximum), and (iii) little evidence for catastrophic oxidation, suggesting the region represents a long-term carbon dioxide sink and global methane source since the early Holocene.