COMPARISON OF DUNE HABITATS OF NORTH MEDITERRANEAN COASTS - TUSCANY (IT) WITH THOSE OF BLACK SEA COASTS -DOBROGEA (RO, BG): SIMILARITIES AND DIFFERENCES

Data related to the floristic and phytocoenotic features of dune areas located in two European coastal areas are reported. These areas are very different by the biogeographical point of view: the coast of Tuscany (Italy, Mediterranean Region, Italo-Thyrrenian province), and the coast of Dobrogea, a cross-border coastal strip between Romania and Bulgaria on the Black Sea (Eurosiberian Region, Escitian province). Both coasts are about 300 km long, and include main habitats (sensu Directive 92/43/EEC) of European coastal dune environments (habitats 1210, 2110, 2120, 2130, 2160, 2210, 2230, 2240, 2250) (Tab. 1). Some habitats have been identified exclusively in a specific geographical area (H2210, H2230, H2240, H2250 only in Tuscan coast (T), H2130, H2160 only in Dobrogea (D), some common to both (H1210, H2110, H2120) (Fig.1) (1, 2). A gradual increase of stenomediterranean species (Tuscany) or eurimediterranean species (Dobrogea) proceeding from north to south was found; as well as a high floristic diversity between the two compared bioregions even within the same habitats. Finally the floristic difference tends to increase from foredune habitats to fixed dunes. This is related mainly to phytoclimatic, phytogeographical, ecological and geomorphological factors. In both study areas a discontinue presence of some foredune habitats (eg. H1210, H2110, H2120) due to anthropic alterations was found.