Evidence for Permafrost Thaw and Transport from an Alaskan North Slope Watershed

Kathryn M. Schreiner, Thomas S. Bianchi, Brad E. Rosenheim

Research output: Contribution to journalArticlepeer-review

Abstract

Burial of organic carbon (OC) in marine sediments is one of the most important linkages between the short-term biologic carbon cycle and the long-term geologic carbon cycle. Yet much is still unknown about the fate of terrigenous OC in marine coastal margins. Here the delivery of particulate OC (POC) to the Colville River deltaic region in the Alaskan Beaufort Sea by particulates of varying densities is studied through the use of ramped temperature pyrolysis and radiocarbon analyses. The Colville River is the largest river in North America whose watershed is underlain completely by high Arctic permafrost tundra. A variety of sources of POC are considered, including terrestrial soils, Pleistocene-aged yedoma-like sediments, coastal peat erosion, and marine POC. We provide the first evidence that riverine POC from the Colville River contains old (Pleistocene-sourced) OC, suggesting ongoing thaw and mobilization of yedoma-like permafrost OC from this northern Alaskan watershed. Additionally, much of this OC appears to be fairly labile and therefore could be readily oxidized and returned to the atmosphere.

Original languageAmerican English
JournalGeophysical Research Letters
Volume41
DOIs
StatePublished - Jan 1 2014
Externally publishedYes

Keywords

  • POC
  • Colville River
  • Beaufort Sea
  • permafrost thaw
  • radiocarbon
  • ramped-temperature pyrolysis

Disciplines

  • Life Sciences

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