La vegetación dunícola en el frente costero de la Pampa Austral (Partido de Coronel Dorrego, Buenos Aires)

two groups of plant communities can be distinguished along the atlantic coast of buenos aires: the northern littoral associations and the austral coast associations. the coronel dorrego district (buenos aires province) exhibits a wide coastal fringe, representing the austral coast dunes flora. vegetation composition and structure, habitat types and the associated geoforms were characterized in the marine coastal fringe of the district. the fixed/semifixed dunes contain psammophytic grasslands and shrublands and high plant cover. in the dune slacks the familias juncaceae, poaceae and cyperaceae dominate. in the upper beach dominates spartina ciliata. the active dunes vegetation shows a mixed steppe physiognomy. the active and fixed/semifixed dunes gather floristic elements particular from the austral pampean district. the presence of regional endemisms (senecio bergii hieron, baccharis divaricata hauman) is verified. a qualitative comparison between this locality and other coastal localities of buenos aires is performed, suggesting that the observed changes in the floristic composition of the coastal dunes along the latitudinal gradient occur differentially in the different geomorphological sectors. finally, the high ecological value of the zone is remarked and its great potential to widen the representativeness of the austral coast floristic elements in the system of nature reserves is emphasised.