A challenging study to address the complexity of extreme and threatened habitats: the BioAlpEC project (Biodiversity of Alpine Ecosystems in a Changing world)

Alpine ecosystems are unique in their extreme heterogeneity due to topography, geomorphology, geophysics, and microclimatic conditions. They are particularly exposed to climate change, with the regression of the snowline and thawing of glaciers inducing profound modifications to all habitats. While the timber line shifts upslope, freshwater bodies undergo radical changes in water regime and persistence. Forests exposed to extreme climatic events experience outbreaks of plant or animal invasive species and parasites, taking advantage of weakened communities. This scenario is made additionally complex by other forms of anthropogenic pressure; for example, although the abandonment of traditional landuse has made habitats available to an expanding large mammal community, the denser network of roads and trails and their increased used for outdoor activities have enhanced the potential for human-wildlife conflict. Here we used a multiscale, multi-level approach to assess how these cascading effects have impacted biodiversity, pooling an ensemble of techniques and methodologies. From metagenomics of bioaerosol, ecto- and endo- microbial communities, and freshwater protists and metazoans to comparative genomics of flora and population genomics of endemic vertebrate species; from population demography of invertebrates and mammals to remote sensing of forest, grassland, and mammals’ occurrence, and bio-logging of free-ranging ungulates, the BioAlpEC project is unravelling a gradient of biodiversity threats, but also of species’ resilience and responses that are rapidly re-shaping the dynamics and functions of Alpine ecosystems.