EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

The role of dispersal limitation in the post-glacial forest expansion of southern and central Europe

Deborah Zani1,2, Heike Lischke1, and Veiko Lehsten1,2
Deborah Zani et al.
  • 1Swiss Federal Institute for Forest, Snow and Landscape Research WSL
  • 2Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden

The global vegetation cover underwent strong changes during the past glacial cycle. These have been driven by climatic fluctuations but also by spatiotemporal vegetation dynamics, including migration to new climatologically suitable areas and interactions with other species. However, how much migration lag contributed to the vegetation change after the Last Glacial Maximum (LGM) is often not clear. We used the newly-implemented model LPJ-GM 2.0 to simulate the vegetation change of southern and central Europe from the end of the LGM (18.5 ka) to the preindustrial era (1.5 ka). The model couples a migration module to the dynamic global vegetation model LPJ-GUESS, thus allowing species to migrate simultaneously while interacting with each other. We compared two dispersal settings (free dispersal and dispersal limitation) against pollen data to test the reliability of the migration module to provide realistic paleo-vegetation reconstructions for biome and species distributions. Furthermore, we calculated range shifts of the leading edges and centroids to detect potential species-specific migration lags and range filling delays across simulation time. Our results show that the setting with dispersal limitation is better at capturing the initial post-glacial expansion of non-boreal forests in southern and central Europe than the scenario assuming free dispersal. Range shift analysis shows significant migration lags for most tree species at times of sudden temperature rise (start of the Bølling–Allerød warming event and following the Younger Dryas). Overall, our study suggests that it is necessary to include migration processes when simulating vegetation range expansion under rapid climate change, with implications for future vegetation projections.

How to cite: Zani, D., Lischke, H., and Lehsten, V.: The role of dispersal limitation in the post-glacial forest expansion of southern and central Europe, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-1311,, 2023.