High biolability of ancient permafrost carbon upon thaw
Article first published online: 14 JUN 2013
©2013. American Geophysical Union. All Rights Reserved.
Geophysical Research Letters
Volume 40, Issue 11, pages 2689–2693, 16 June 2013
How to Cite
2013), High biolability of ancient permafrost carbon upon thaw, Geophys. Res. Lett., 40, 2689–2693, doi:10.1002/grl.50348., et al. (
- Issue published online: 3 JUL 2013
- Article first published online: 14 JUN 2013
- Accepted manuscript online: 15 MAR 2013 09:24AM EST
- Manuscript Accepted: 8 MAR 2013
- Manuscript Revised: 7 MAR 2013
- Manuscript Received: 11 JAN 2013
- dissolved organic carbon;
- Kolyma River
 Ongoing climate warming in the Arctic will thaw permafrost and remobilize substantial terrestrial organic carbon (OC) pools. Around a quarter of northern permafrost OC resides in Siberian Yedoma deposits, the oldest form of permafrost carbon. However, our understanding of the degradation and fate of this ancient OC in coastal and fluvial environments still remains rudimentary. Here, we show that ancient dissolved OC (DOC, >21,000 14C years), the oldest DOC ever reported, is mobilized in stream waters draining Yedoma outcrops. Furthermore, this DOC is highly biolabile: 34 ± 0.8% was lost during a 14 day incubation under dark, oxygenated conditions at ambient river temperatures. Mixtures of Yedoma stream DOC with mainstem river and ocean waters, mimicking in situ mixing processes, also showed high DOC losses (14 days; 17 ± 0.8% to 33 ± 1.0%). This suggests that this exceptionally old DOC is among the most biolabile DOC in any previously reported contemporary river or stream in the Arctic.