Floristic and phytosociology of a grazed grassland at Fazenda Experimental da Ressacada, Florianópolis, Santa Catarina, southern Brazil

Abstract

The Brazilian coastal grasslands are a relatively recent vegetation located in lowland areas with hydromorphic soils in the country seaside. This plant formation is predominantly composed of prostrate, stoloniferous and/or rhizomatous species of families Poaceae, Cyperaceae, Asteraceae, and Fabaceae. We performed a phytosociological and floristic survey on a grazed area of the coastal grasslands, located at Fazenda Experimental da Ressacada, Florianópolis municipality, aiming to record the frequent, rare, exotic, endemic and threatened species therein. In the floristic survey, we adopted the “walking” method. We found 91 species from 23 families, Cyperaceae being one of the most representative families in the plant formation. No endangered and/or endemic species were found, yet eight exotic species were recorded. In the phytosociological study, we adopted the surface method, randomly distributing 30 plots of 1 m². We recorded 76 species from 23 families. The species with highest importance value index was Ischaemum minus J.Presl, as previously reported by studies conducted on coastal grasslands of Rio Grande do Sul state, southern Brazil. In the study area, native species had high frequency and high soil cover, which shows that although the area has undergone changes due to anthropic activity (such as introduction of exotic species), the plant formation is still dominated by native species, thus revealing the great regeneration capacity of the coastal grasslands.