, 40:683 | Cite as

Tree and Shrub Expansion Over the Past 34 Years at the Tree-Line Near Abisko, Sweden

  • Sara Rundqvist
  • Henrik Hedenås
  • Anneli Sandström
  • Urban Emanuelsson
  • Håkan Eriksson
  • Christer Jonasson
  • Terry V. Callaghan


Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic Sweden. We recorded the change in coverage of shrub and tree species over a 32– to 34-year period, in three 50 × 50 m plots; in the alpine-tree-line ecotone. The cover of shrubs and trees (<3.5 cm diameter at breast height) were estimated during 2009–2010 and compared with historical documentation from 1976 to 1977. Similarly, all tree stems (≥3.5 cm) were noted and positions determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory.


Vegetation change Tree-line Shrubs Sub-Arctic Herbivory Human impacts 



The authors would like to acknowledge Nils-Åke Andersson for providing them with unpublished data and photographs from 1976–1977, Craig Tweedie, and an anonymous reviewer for valuable comments. The authors also sincerely thank the staff on Abisko Arctic Scientific Research Station for their logistic support. The project was financed by a grant from the Swedish Research Council (Vetenskapsrådet) 327-2007-833.


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Copyright information

© Royal Swedish Academy of Sciences 2011

Authors and Affiliations

  • Sara Rundqvist
    • 1
  • Henrik Hedenås
    • 2
  • Anneli Sandström
    • 3
  • Urban Emanuelsson
    • 4
  • Håkan Eriksson
    • 1
  • Christer Jonasson
    • 2
  • Terry V. Callaghan
    • 5
    • 6
  1. 1.Umeå Univerity, EMGUmeåSweden
  2. 2.Abisko Scientific Research StationAbiskoSweden
  3. 3.GävleSweden
  4. 4.Swedish Biodiversity CenterUppsalaSweden
  5. 5.Royal Swedish Academy of SciencesStockholmSweden
  6. 6.Department of Animal and Plant SciencesUniversity of SheffieldWestern Bank, SheffieldUK

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