EGU22-9657
https://doi.org/10.5194/egusphere-egu22-9657
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Particulate organic carbon composition and landscape characteristics in the Peel River Watershed, Canada

Kirsi Keskitalo1, Niek Speetjens1, Paul Overduin2, Sebastian Westermann3, Frederieke Miesner2, Torsten Sachs4, Ingmar Nitze2, Lisa Bröder5, Negar Haghipour5,6, Timothy Eglinton5, and Jorien Vonk1
Kirsi Keskitalo et al.
  • 1Department of Earth Sciences Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
  • 2Alfred Wegener Insitute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
  • 3Department of Geosciences University of Oslo, Oslo, Norway
  • 4German Research Centre for Geosciences, Potsdam, Germany
  • 5Department of Earth Sciences Swiss Federal Institute of Technology, Zürich, Switzerland
  • 6Laboratory of Ion Beam Physics Swiss Federal Institute of Technology, Zürich, Switzerland

Rapid warming of the Arctic is accelerating thaw of permafrost, which mobilizes organic carbon (OC). Remineralization of this carbon can contribute to further climate warming. The Peel River watershed is underlain by continuous and discontinuous permafrost and covers a diverse set of landscapes from wetlands to barren mountainous areas. Part of the watershed undergoes abrupt permafrost thaw that releases particulate OC (POC) to the fluvial system. In this study, we couple landscape characteristics to river POC to better understand its spatial variability and the changes imposed on the watershed by permafrost thaw. We sampled POC in July-August 2019 in the Peel River main stem and its tributaries (total n=~120) and used carbon isotopes and lipid biomarkers to characterize its composition and trace its sources. Our first results indicate a compositional diversity within the watershed as POC ranges between <0.1 and 2.1 mg L-1, δ13C-POC from -36.7 to -26.5‰ and Δ14C-POC from -906.4 to -43.5‰. Ongoing changes in the watershed can be traced within its waters, and may help us to decipher how it is changing and may change in the future.

How to cite: Keskitalo, K., Speetjens, N., Overduin, P., Westermann, S., Miesner, F., Sachs, T., Nitze, I., Bröder, L., Haghipour, N., Eglinton, T., and Vonk, J.: Particulate organic carbon composition and landscape characteristics in the Peel River Watershed, Canada, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9657, https://doi.org/10.5194/egusphere-egu22-9657, 2022.