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E.S. Meier et al. 2010. Projections of shifts in species distributions
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Projections of shifts in species distributions: assessing the influence of
macro-climate and local processes
Eliane S. Meier * , Felix Kienast & Niklaus E. Zimmermann
Land Use Dynamics, Swiss Federal Research Institute WSL, Zürcherstrasse 111,
CH-8903 Birmensdorf, Switzerland
Abstract
It is currently unclear, whether tree species will be able to keep pace with the ongoing
and likely accelerating shift in climate. Here, we estimated the influence of changing
macro-climate and local processes on shifts in species distributions. First, we evaluated
tree co-occurrence patterns in climate space and estimated the influence of these
patterns on current and future species distributions using species distribution models.
Second, we combined these models with migration rates from a process-model and a
GIS path cost analysis, to estimate key processes influencing tree migration rates and to
predict more realistic shifts in large-scale tree re-distributions. Our results showed, that
biotic interactions mainly limited species distributions towards favorable growing
conditions, while climate was directly limiting primarily where biotic interactions were
low. Landscape fragmentation was further strongly limiting migration. In conclusion,
this may lead to considerable time lags in range shifts and re-adjustment to new
conditions during climate change, especially for late succession species.
Keywords: biotic interactions, macro-climate, Europe, niche-based model, stress-gradient
hypothesis.
1. Introduction
Macroclimate is hypothesized to play a key role in large-scale species distributions (Thuiller,
Araújo and Lavorel 2004, Woodward 1987, Whittaker, Willis and Field 2001), and thus, the
changing climate is expected to shift the distribution of suitable habitats for many species
considerably (Root et al. 2003, Parmesan and Yohe 2003). This expectation is consistent with
observations during Holocene climate changes, where species adapted their spatial distribution
more or less rapidly to the changing climate conditions (Davis and Shaw 2001). For on-going
and future climate change, however, it remains unclear whether species will be able to keep
pace with accelerating rates of change (Iverson, Schwartz and Prasad 2004). On the one hand,
new dispersal limitations emerge, such as anthropogenic landscape-fragmentation that may
cause the newly emerging suitable habitats to be insufficiently connected. On the other hand, the
expected global warming is predicted to be one or more orders of magnitude faster than past
climate change events (Solomon and Kirilenko 1997, Etterson and Shaw 2001) and the
influence on range shifts by small-scale processes limiting species establishment, survival and
dispersal, such as biotic interactions (e.g. inter-specific competition, facilitation) or disturbances
were so far often ignored in analysis on large-scale species responses to climate change (Caplat,
Anand and Bauch 2008, Brooker et al. 2007). According to the 'stress-gradient hypothesis',
* Corresponding author. Tel.: +41 44 7392 560 - Fax: +41 44 7392 215
Email address: eliane.meier@wsl.ch
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.