Andreas Persson

Andreas Persson

Senior lecturer

Andreas Persson

Total waterborne carbon export and DOC composition from ten nested subarctic peatland catchments—importance of peatland cover, groundwater influence, and inter-annual variability of precipitation patterns

Author

  • David Olefeldt
  • Nigel Roulet
  • Reiner Giesler
  • Andreas Persson

Summary, in English

Waterborne carbon (C) export from terrestrial ecosystems is a potentially important flux for the net catchment C balance and links the biogeochemical C cycling of terrestrial ecosystems to their downstream aquatic ecosystems. We have monitored hydrology and stream chemistry over 3 years in ten nested catchments (0.6–15.1 km2) with variable peatland cover (0%–22%) and groundwater influence in subarctic Sweden. Total waterborne C export, including dissolved and particulate organic carbon (DOC and POC) and dissolved inorganic carbon (DIC), ranged between 2.8 and 7.3 g m–2 year–1, representing ~10%–30% of catchment net ecosystem exchange of CO2. Several characteristics of catchment waterborne C export were affected by interacting effects of peatland cover and groundwater influence, including magnitude and timing, partitioning into DOC, POC, and DIC and chemical composition of the exported DOC. Waterborne C export was greater during the wetter years, equivalent to an average change in export of ~2 g m–2 year–1 per 100 mm of precipitation. Wetter years led to a greater relative increase in DIC export than DOC export due to an inferred relative shift in dominance from shallow organic flow pathways to groundwater sources. Indices of DOC composition (SUVA254 and a250/a365) indicated that DOC aromaticity and average molecular weight increased with catchment peatland cover and decreased with increased groundwater influence. Our results provide examples on how waterborne C export and DOC composition might be affected by climate change. Copyright © 2012 John Wiley & Sons, Ltd.

Department/s

  • Dept of Physical Geography and Ecosystem Science

Publishing year

2013

Language

English

Pages

2280-2294

Publication/Series

Hydrological Processes

Volume

27

Issue

16

Document type

Journal article

Publisher

John Wiley and Sons

Topic

  • Physical Geography

Keywords

  • dissolved organic carbon (DOC)
  • peatlands
  • discontinuous permafrost
  • dissolved inorganic carbon (DIC)
  • subarctic
  • groundwater

Status

Published

ISBN/ISSN/Other

  • ISSN: 1099-1085