published variant
Systems Ecology Report:
Fischlin, A. & Bugmann, H. (1993): Comparing the Behaviour of Mountainous Forest Succession Models in a Changing Climate Systems Ecology Report No. 16, Institute of Terrestrial Ecology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland, 14 pp.
Abstract:
The temporal behaviour of three forest gap models built to simulate species succession in central Europe is compared in the current as well as future climates. The first model, FORECE, represents a conventional forest gap model, the second, FORCLIM 1.1, is an ecologically simplified descendant of the first, and the third model, FORCLIM 1.3, was derived from the second by avoiding any implicit climate dependencies. The species compositions produced by the three models were studied along an altitudinal gradient in the European Alps while manipulating climatic parameters. First, the equilibrium states of the models were calculated for the present climate. Second, starting from the equilibrium states, the step responses of the models were explored by imposing an instantaneous climatic change based on regional projections, which have been statistically downscaled from transient GCM simulations for the next century. According to similarity coefficients all three models produce similar equilibrium species compositions in the present climate. In a changed climate the results suggest that central European forests at high altitudes are more susceptible to temperature changes and that lower forests are more susceptible to precipitation changes. However, some models produce a markedly differing behaviour in a changed climate. Hence, contrary to wide-held expectations, this type of models needs to be thoroughly revised before forest gap models may be applied to assess in details the impacts of climatic change impacts on forests.