Tundra landscape heterogeneity, not interannual variability, controls the decadal regional carbon balance in the Western Russian Arctic

Research output: Contribution to journalArticle

Abstract

Across the Arctic, the net ecosystem carbon (C) balance of tundra ecosystems is highly uncertain due to substantial temporal variability of C fluxes and to landscape heterogeneity. We modeled both carbon dioxide (CO2) and methane (CH4) fluxes for the dominant land cover types in a ~100-km2 sub-Arctic tundra region in northeast European Russia for the period of 2006–2015 using process-based biogeochemical models. Modeled net annual CO2 fluxes ranged from −300 g C m−2 year−1 [net uptake] in a willow fen to 3 g C m−2 year−1 [net source] in dry lichen tundra. Modeled annual CH4 emissions ranged from −0.2 to 22.3 g C m−2 year−1 at a peat plateau site and a willow fen site, respectively. Interannual variability over the decade was relatively small (20%–25%) in comparison with variability among the land cover types (150%). Using high-resolution land cover classification, the region was a net sink of atmospheric CO2 across most land cover types but a net source of CH4 to the atmosphere due to high emissions from permafrost-free fens. Using a lower resolution for land cover classification resulted in a 20%–65% underestimation of regional CH4 flux relative to high-resolution classification and smaller (10%) overestimation of regional CO2 uptake due to the underestimation of wetland area by 60%. The relative fraction of uplands versus wetlands was key to determining the net regional C balance at this and other Arctic tundra sites because wetlands were hot spots for C cycling in Arctic tundra ecosystems.

Details

Authors
  • Claire C. Treat
  • Maija E. Marushchak
  • Carolina Voigt
  • Yu Zhang
  • Zeli Tan
  • Qianlai Zhuang
  • Tarmo A. Virtanen
  • Aleksi Räsänen
  • Christina Biasi
  • Gustaf Hugelius
  • Dmitry Kaverin
  • Paul A. Miller
  • Martin Stendel
  • Vladimir Romanovsky
  • Felix Rivkin
  • Pertti J. Martikainen
  • Narasinha J. Shurpali
Organisations
External organisations
  • University of Eastern Finland
  • Pacific Northwest National Laboratory
  • Purdue University
  • University of Helsinki
  • Norwegian University of Science and Technology
  • Stockholm University
  • Danish Meteorological Institute
  • University of Alaska Fairbanks
  • Natural Resources Canada
  • Russian Academy of Sciences
  • Lomonosov Moscow State University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Geography

Keywords

  • ecosystem modeling, methane, net ecosystem CO exchange, peatland, permafrost, regional carbon balance, Russia, Tundra
Original languageEnglish
Pages (from-to)5188-5204
JournalGlobal Change Biology
Volume24
Issue number11
Publication statusPublished - 2018
Publication categoryResearch
Peer-reviewedYes