Biogeographical and Ecological Patterns of the Bryophytic Flora Inhabiting the Small Islands Surrounding the Italian Peninsula, Sicily and Sardinia

Bryophytes' adaptability and stress resistance make them excellent colonizers. Moreover, bryophytes are key components of almost all terrestrial ecosystems from aquatic to arid to freezing cold. Bryophytes are also unique models to study adaptation and stress resistance in plants. Bryological studies in the Mediterranean area are mainly floristic-oriented, and consequently, the knowledge of the autoecology of the species inhabiting Mediterranean islands and islets is very scarce. The aim of this study is to evaluate bryophyte diversity in a number of islands and islets surrounding the Italian peninsula, Sicily and Sardinia. Moreover, based on the geographical and environmental features available for the studied islands, we analyze the role of different ecological variables (such as the islands' area, insularity degree, altitude, and substratum type) in shaping bryophytic species richness and diversity. In the present study, ecological indicators adapted to Mediterranean bryophytes were also used to describe from an ecological and functional viewpoint the species inhabiting the studied islands and to explore to what extent the islands' features have had a role in shaping the ecological features of the bryophytic floras inhabiting them. Within this study, an updated overview on the floristic richness and diversity of the small islands surrounding the Italian peninsula, Sicily and Sardinia was presented. The subject of the discussion was the island-related floristic and ecological differences as well as the drivers of these differences.