Expected impacts of climate change on tree ferns distribution and diversity patterns in subtropical Atlantic Forest

Abstract Tree ferns are common elements in the Atlantic Forest domain, sometimes reaching more than half of total dominance at forest sites. Just as in most groups, climate change might impact the distribution and diversity of tree ferns. To investigate the extent of these impacts in the subtropical Atlantic Rainforest, we measured the changes in species distribution, α- and β-diversity between current climate and future climatic scenarios for 2050. Most tree ferns species tend to have their area reduced. Hence, species richness tends to decrease in the future, especially in the Rainforest sites. In general, β-diversity tend to not change on the regional scale, but some sites can have their relative singularity in composition affected. Protected Areas (PAs) in subtropical Atlantic Forest harbor more α-diversity than sites outside PAs — the same applies to β-diversity. Our study offers new insights on the effects of climate change in tree ferns by integrating the evaluation of its impacts on distribution, α-, and β-diversity in all study areas and inside PAs.