Specie vegetali esotiche negli ambienti costieri sabbiosi di alcune regioni dell'Italia centrale

Mediterranean coastal dunes are affected by high levels of human disturbance, particularly in the last years. Disturbance not only promotes a physical alteration that increase the invasibility of coastal dunes, but also allows the arrival of new alien plant propagules. This study examined the current distribution of the alien species growing on recent (Holocenic) coastal dunes in central Italy (Latium, Abruzzo and Molise regions), considering alien origin, invasive status and growth form strategies. The floristic sampling was carried out following the European Cartographic Project protocol and 91 quadrants were examined. Consistent numbers of non-native species and clear differences between the Tyrrhenian and the Adriatic coast were found. America represented the continent which provides the highest number of aliens species. However, higher values of alien species coming from the Tropical America and Africa were found in the Thyrrenian coast, while higher values of aliens coming from the Extra- Tropical America and Eurasia were found in the Adriatic coast. Most alien species were casuals while the number of invasive aliens was relatively much lower. Finally, the success of invasive aliens appeared to be related to both annual or perennial evergreen strategies.