Flora da Serra da Pedra Branca, Caldas, Minas Gerais, Brasil

Abstract

Serra da Pedra Branca is located in the southwestern of Minas Gerais state, municipality of Caldas (21 ° 58 '- 55' S and 46 ° 24 '-22' W). Striking feature in the landscape, the region is part of the Atlantic Forest biome and is considered priority area for conservation the flora in Minas Gerais state. The aims of this paper were the elaboration of a floristic checklist of Serra da Pedra Branca with emphasis on the vegetation of Campos de Altitude, compare the flora of the Serra da Pedra Branca with the flora collected by Anders Fredrik Regnell in the nineteenth century in Caldas and analyse the floristic similarity between areas of rock outcrops. For that, monthly collections were made from March 2008 to February 2009. The floristic survey recorded 340 vascular plant species and 46 identified only up to genus level. The following families are important for their species richness among the angiosperms: Orchidaceae (27 spp.), Asteraceae and Rubiaceae (16 spp. each one), Piperaceae and Fabaceae (15 spp. each one), Bromeliaceae (14 spp.), Solanaceae (10 spp) and Poaceae (nine spp.), and among the ferns: Polypodiaceae (15 spp.) and Aspleniaceae (eight spp.). Herbs represent 56,5% of the flora, followed by trees (21,8%), shrubs (15,3%), climbers (5,9%) and arborescent (0,6%). Comparing the current floristic data with the data collected by Anders Fredrik Regnell in Caldas in the nineteenth century, indicates the presence of 90 species in common to both listings. In general, the diversity over the years did not differ despite the richness within some families have been quite different. The intense degradation and removal of vegetation occurred in the municipality of Caldas over the years to open pastures, agriculture and mining may have caused the disappearance of several species and the establishment of others. The analysis of floristic similarity between the flora of Campos de Altitude da Serra da Pedra Branca and other areas of rocky outcrops located in southeastern of Minas Gerais state and Rio de Janeiro, showed a greater proximity of the Serra da Pedra Branca with areas of Campos Rupestres which can be explained by the influence of the cerrado in the floristic of these environments. The vegetation of the Serra da Pedra Branca is considered an endangered environment since the presence of endangered species and / or endemic, associated with local environmental conditions with accelerated rate of destruction, highlight the need for urgent action to preserve local biodiversity.