GLACIAL SPECIALIST SPECIES ARE MORE VULNERABLE TO CLIMATE CHANGE THAN GENERALIST SPECIES (DRAWING PARELLELS BETWEEN EMPIRICAL AND ECOLOGICAL DISTINCTIONS)

A recent study has revealed that glacial specialist plant species are more susceptible to the impacts of climate change compared to generalist species. This is especially true in Switzerland, where glaciers are expected to diminish significantly by the end of the century. As the glaciers recede, glacial specialists face a lack of suitable habitats to relocate to, potentially leading to a decline in Swiss mountain floral biodiversity and the associated ecosystem services.

Researchers utilized Species Distribution Models (SDMs) of 369 plant species found in Swiss proglacial areas. These models were developed using various bioclimatic, lithological, and topographic variables. The study compared two methods for identifying glacial specialist species: empirical, based on the degree of persistence of species in proglacial areas, and ecological, utilizing Landolt values.

Both approaches yielded comparable results, with both generalist and glacial specialist species' distributions being predominantly influenced by bioclimatic variables. However, the dependence on bioclimatic variables was significantly stronger for glacial specialists.

Conversely, the distributions of generalist species were more strongly influenced by topographical and lithological factors. This suggests that glacial specialists are more vulnerable to climate change, as they have fewer available habitats to migrate to as their current habitats shrink due to glacier retreat. Consequently, preserving glacial specialist plant species and maintaining Swiss mountain floral biodiversity will be a major challenge in the face of climate change.