Habitat and island area and isolation as drivers of community assembly in an archipelago.

Aim of this paper is to investigate the spatial scaling patterns in the plant communities of the Tuscan archipelago, one of the most thoroughly investigated areas of the Mediterranean basin in terms of vascular flora and having been subject to intense vegetation sampling. The specific hypotheses that we wish to test are: 1) Habitat area predicts species richness within island as island area predicts total species richness; 2) habitat type and extent are more important than island identity in controlling species composition. The analyses of ISAR and HSAR highlighted the major role of habitat area in controlling species richness patterns within island and community composition, even if the island identity signal was also clear as predicted by island biogeography theories.