Monitoring Networks for Testing Model-Based Scenarios of Climate Change Impact on Mountain Plant Distribution

Abstract

In recent years, predictive modelling of plant species' distribution has been shown to be a powerful method for obtaining preliminary assessments of potential ecological impact of rapid climatic change (e.g. Brzeziecki et al. 1995; Kienast et al. 1996; Saetersdal and Birks 1997; Iverson and Prasad 1998; Lischke et al. 1998; Gottfried et al. 1999; Guisan and Theurillat 2000; 2001; Bakkenes et al. 2002). Such models give static results: they reveal where suitable species' habitats might be located in a climatically changed future, but they do not explicitly consider all the processes leading to the predicted changes. A basic assumption behind their application is thus to consider present and future distributions of species to be in equilibrium, or at least in pseudo-equilibrium, with their environment (Guisan and Theurillat 2000). Although this assumption obviously does not hold in all ecological situations, scenarios obtained from these models nevertheless constitute an interesting spatially-explicit and quantitative basis for discussing how climate change might impact plant distribution. Examples of such discussions are provided in the next section.