Volume XV |

Floristic composition and functional zones pattern of the beach-dune system along the Danube Delta coast – Romania

Abstract: This paper presents the floristic composition of vegetation for each feature on a beach-dune system sector from the western Black Sea coast, Romania. The studied site is a relatively small fragment of the 10 km shore on the southern part of the Danube Delta Biosphere Reserve (DDBR) that may be susceptible to anthropogenic pressure in the coming years. Out of the 38 identified species, ten are threatened species according to the national Red List of endangered plant species. Compositae and Poaceae are the families with the highest number of species. The analysis of floristic spectrum shows a mixture of elements of plant communities, but Pontic and Ponto-Caspian elements are prevalent.
Physiognomically, the foredunes in the Danube delta coast have a typical morphology, with a smooth profile and do not exceed 2 m high. They are vegetated by herbaceous annual and perennial plants, but in terms of abundance the native dune builder rhizomatous grasses are rare.
The fore dunes from this Black Sea coast sector serve as vital habitat and refuge for Convolvulus persicus L. within the western limit of its geographical range. This endemic Ponto-Caspian element defines a particular habitat type within the Black Sea biogeographic region: “Pontic shore dunes with Convolvulus persicus L.” Currently, the main threats of this habitat are cattle grazing and the increasing touristic activities (human trampling, horse riding and all-terrain vehicle riding).