Biogeosciences, 15, 1969–1985, 2018 https://doi.org/10.5194/bg-15-1969-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 3.0 License. Substrate potential of last interglacial to Holocene permafrost organic matter for future microbial greenhouse gas production Janina G. Stapel1, Georg Schwamborn2, Lutz Schirrmeister2, Brian Horsfield1, and Kai Mangelsdorf1 1GFZ, German Research Centre for Geoscience, Helmholtz Centre Potsdam, Organic Geochemistry, Telegrafenberg, 14473 Potsdam, Germany 2Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Department of Periglacial Research, Telegrafenberg, A43, 14473 Potsdam, Germany Correspondence: Kai Mangelsdorf (
[email protected]) Received: 14 March 2017 – Discussion started: 17 March 2017 Revised: 2 February 2018 – Accepted: 6 February 2018 – Published: 4 April 2018 Abstract. In this study the organic matter (OM) in sev- 1 Introduction eral permafrost cores from Bol’shoy Lyakhovsky Island in NE Siberia was investigated. In the context of the observed The northern areas of the Eurasian landmass are under- global warming the aim was to evaluate the potential of lain by permafrost, which is defined as ground that remains freeze-locked OM from different depositional ages to act as colder than 0 ◦C for at least 2 consecutive years (Washburn, a substrate provider for microbial production of greenhouse 1980). These areas contain a large reservoir of organic car- gases from thawing permafrost. To assess this potential, the bon freeze-locked in the permafrost deposits (French, 2007; concentrations of free and bound acetate, which form an Zimov et al., 2009). Hugelius et al. (2014) estimated that appropriate substrate for methanogenesis, were determined.