Forests below rocky cliffs often play a very important role in protecting settlements against rockfall. The structure and development of these forests are expected to be substantially affected by the disturbance of the falling rocks. Knowing about this effect is important to predict the development of protection forests and consider potential effects of the falling blocks in management strategies. The goal of this study is to...

Ongoing rapid climate change is predicted to cause local extinction of plant species in mountain regions. However, some plant species could have persisted during Quaternary climate oscillations without shifting their range, despite the limited evidence from fossils. Here, we tested two candidate mechanisms of persistence by comparing the macrorefugia and microrefugia ( MR ) hypotheses. We used the rare and endemic Saxifraga fl...

Aim The aim of this study was to test, based on biological theory, which facet of temperature is most closely associated with the elevational and latitudinal low‐temperature limits of seven European broad‐leaved tree species. We compared three temperature‐related potential constraints across three study regions: (1) absolute minimum temperature within 100 years; (2) lowest temperatures during the period of bud‐break; and (3) l...

Aim We compared the upper limits of 18 deciduous tree species with respect to elevation in S witzerland and latitude in E urope. We hypothesized that species would exhibit the same relative positions along elevation and latitude, which can be expected if species have reached their thermal cold limit along both gradients. Location E urope and S witzerland. Methods We developed a method to identify a least biased estimate of the...

Aim Understanding the stability of realized niches is crucial for predicting the responses of species to climate change. One approach is to evaluate the niche differences of populations of the same species that occupy regions that are geographically disconnected. Here, we assess niche conservatism along thermal gradients for 26 plant species with a disjunct distribution between the A lps and the A rctic. Location E uropean A l...

Aim Climatic niche modelling of species and community distributions implicitly assumes strong and constant climatic determinism across geographical space. We tested this assumption by assessing how stacked‐species distribution models ( S ‐ SDMs ) perform for predicting plant species assemblages along elevation gradients. Location The western S wiss A lps. Methods Using robust presence–absence data, we first assessed the abilit...

Aim The physical and physiological mechanisms that determine tree‐line position are reasonably well understood, but explanations for tree species‐specific upper elevational limits below the tree line are still lacking. In addition, once these uppermost positions have been identified, questions arise over whether they reflect past expansion events or active ongoing recruitment or even upslope migration. The aims of this study w...

Mountain ecosystems will likely be affected by global warming during the 21st century, with substantial biodiversity loss predicted by species distribution models (SDMs). Depending on the geographic extent, elevation range, and spatial resolution of data used in making these models, different rates of habitat loss have been predicted, with associated risk of species extinction. Few coordinated across‐scale comparisons have bee...

The usefulness of species distribution models (SDMs) in predicting impacts of climate change on biodiversity is difficult to assess because changes in species ranges may take decades or centuries to occur. One alternative way to evaluate the predictive ability of SDMs across time is to compare their predictions with data on past species distributions. We use data on plant distributions, fossil pollen and current and mid‐Holoce...

Aim To assess the geographical transferability of niche‐based species distribution models fitted with two modelling techniques. Location Two distinct geographical study areas in Switzerland and Austria, in the subalpine and alpine belts. Methods Generalized linear and generalized additive models (GLM and GAM) with a binomial probability distribution and a logit link were fitted for 54 plant species, based on topoclimatic predi...