Conservation and restoration strategies to preserve the variability of cork oak Quercus suber-a Mediterranean forest species-under global warming

Climate change effects on forest ecosystems are a matter of debate within the scientific community, given their implications for biodiversity conservation and management. Coupling environmental data and modelling techniques with new advances on species resistance to disturbances, resilience, and new potential colonization areas provides insights that can used in rehabilitation, reconstruction, reclamation, and replacement. Here, we investigated an economically relevant evergreen oak, Quercus suber L. that is naturally distributed in the central-western Mediterranean Basin. Ecological niche modeling (ENM) was applied to statistically forecast the suitability areas of 4 haplotypes, as detected in previous studies. Combining these results with past reconstructions of climatically favourable regions, we identified 22 putative refugia and their climate characteristics that could host cork oak haplotypes. Different responses were observed among haplotypes: some of them were foreseen to expand their range over the next century, others to retreat. Overall, coastal mountains appeared to play a crucial role in the species' conservation. Notably, future scenarios call for a differential type of management for cork oak, considering local conditions and human disturbances. For 3 examples (Apulia, Kabylie and Peloponnese), we analyzed conservation, enrichment, localized reforestation, and assisted migration as strategies to mitigate or prevent the loss of genetic diversity and the extinction risk driven by global warming. The implementation of advanced forest nursery technologies for high quality seedling production are factors recommended for the successful preservation and extension of cork oak presence in the Mediterranean under future climate change.