Aquatic export of young dissolved and gaseous carbon from a pristine boreal fen: implications for peat carbon stock stability

Campeau, A., Bishop, K. H., Billett, M. F., Garnett, M. H. , Laudon, H., Leach, J. A., Nilsson, M. B., Öquist, M. G. and Wallin, M. B. (2017) Aquatic export of young dissolved and gaseous carbon from a pristine boreal fen: implications for peat carbon stock stability. Global Change Biology, 23(12), pp. 5523-5536. (doi: 10.1111/gcb.13815) (PMID:28712133)

Abstract

The stability of northern peatland's carbon (C) store under changing climate is of major concern for the global C cycle. The aquatic export of C from boreal peatlands is recognized as both a critical pathway for the remobilization of peat C stocks as well as a major component of the net ecosystem C balance (NECB). Here, we present a full year characterization of radiocarbon content (14C) of dissolved organic carbon (DOC), carbon dioxide (CO2), and methane (CH4) exported from a boreal peatland catchment coupled with 14C characterization of the catchment's peat profile of the same C species. The age of aquatic C in runoff varied little throughout the year and appeared to be sustained by recently fixed C from the atmosphere (<60 years), despite stream DOC, CO2, and CH4 primarily being sourced from deep peat horizons (2–4 m) near the mire's outlet. In fact, the 14C content of DOC, CO2, and CH4 across the entire peat profile was considerably enriched with postbomb C compared with the solid peat material. Overall, our results demonstrate little to no mobilization of ancient C stocks from this boreal peatland and a relatively large resilience of the source of aquatic C export to forecasted hydroclimatic changes.

• Item Type: Articles
• Additional Information: This study was supported by the Swedish Research Council (contract: 2012–3919 to K. Bishop), the department of Earth Sciences at Uppsala University and the Knut and Alice Wallenberg foundation for financial support. This work was also supported by the Natural Environment Research Council (NERC) Radiocarbon Facility NRCF010001 (allocation number 15.1104 and 1947.1015)
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Garnett, Dr Mark
• Authors: Campeau, A., Bishop, K. H., Billett, M. F., Garnett, M. H., Laudon, H., Leach, J. A., Nilsson, M. B., Öquist, M. G., and Wallin, M. B.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Global Change Biology
• Publisher: Wiley
• ISSN: 1354-1013
• ISSN (Online): 1365-2486
• Published Online: 01 September 2017
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in Global Change Biology 23(12): 5523-5536
• Publisher Policy: Reproduced under a Creative Commons License