Tree line shifts in the Swiss Alps: Climate change or land abandonment?

Détails

ID Serval
serval:BIB_503EC5F62EB9
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Tree line shifts in the Swiss Alps: Climate change or land abandonment?
Périodique
Journal of Vegetation Science
Auteur(s)
Gehrig-Fasel J., Guisan A., Zimmermann N. E.
ISSN
1100-9233
Statut éditorial
Publié
Date de publication
2007
Peer-reviewed
Oui
Volume
18
Numéro
4
Pages
571-582
Langue
anglais
Résumé
Questions: Did the forest area in the Swiss Alps increase between 1985 and 1997? Does the forest expansion near the tree line represent an invasion into abandoned grasslands (ingrowth) or a true upward shift of the local tree line? What land cover / land use classes did primarily regenerate to forest, and what forest structural types did primarily regenerate? And, what are possible drivers of forest regeneration in the tree line ecotone, climate and/or land use change?
Location: Swiss Alps.
Methods: Forest expansion was quantified using data from the repeated Swiss land use statistics GEOSTAT. A moving window algorithm was developed to distinguish between forest ingrowth and upward shift. To test a possible climate change influence, the resulting upward shifts were compared to a potential regional tree line.
Results: A significant increase of forest cover was found between 1650 to and 2450 m. Above 1650 m, 10% of the new forest areas were identified as true upward shifts whereas 90% represented ingrowth, and we identified both land use and climate change as likely drivers. Most upward shift activities were found to occur within a band of 300 m below the potential regional tree line, indicating land use as the most likely driver. Only 4% of the upward shifts were identified to rise above the potential regional tree line, thus indicating climate change.
Conclusions: Land abandonment was the most dominant driver for the establishment of new forest areas, even at the tree line ecotone. However, a small fraction of upwards shift can be attributed to the recent climate warming, a fraction that is likely to increase further if climate continues to warm, and with a longer time-span between warming and measurement of forest cover.
Mots-clé
climatic tree line, forest cover change, forest ingrowth, land use change, moving window analysis, upward shift
Web of science
Création de la notice
24/01/2008 20:06
Dernière modification de la notice
03/03/2018 17:08
Données d'usage