BIOGEOGRAFIA DA ESTEPE DOS CAMPOS GERAIS DO PARANÁ

Abstract

‘Souhtern Grasslands’ is the biogeographical term assigned by the Brazilian Governmentto the natural field extensions present in the Mata Atlântica and Pampa Domains that correspond to the biogeographical provinces ‘Paranaense’ and ‘Pampeana’, respectivelly. The spatial delineation of the Campos District in the Paranaense Province, within the southern portion of the Atlantic Forest Domain comprises the native grasslands of State of Parana (‘Campos Gerais’, ‘Campos de Guarapuava’ and ‘Campos de Palmas’) Santa Catarina (‘Campos de Palmas’ / ‘Água Doce’ and ‘Planalto de Lages’), and Rio Grande do Sul (‘Campos de Cima da Serra’). Despite their homogeneous appearance, ‘Souhtern Grasslands’ may show significant differences in their composition depending on the environmental conditions and the evolution of the flora in the two provinces involved. In this sense, to elucidate the biogeographic relationships of native grasslands of the ‘Campos Gerais’ in Paranaense Province means establish whether the plant communities comprise marginal areas of geographic scale or, conversely, compound species dispersal center, or even species routes from dispersion centers out of ‘Campos Gerais’. This study therefore aims to determine the biogeographical relationships among remnants of native grasslands in the Escarpa Devoniana Environmental Protection Area. For this, we used a presence/absence matrix composed by 414 species from phytosociological data, and 1,375 species from floristic surveys from nine plant communities: CPI - Piraí da Serra, EGU - Guartelá State Park, SJ – São João River, CPG - Pitangui Valley, CAP – Capão da Onça, FG / BP - Furnas Gêmeas and Buraco do Padre, CIA - IAPAR Model Farm, EVV - Vila Velha State Park, and CBN – Ponte dos Arcos. Just two of them are within protect areas. It were calculated the Biogeographycal Similarity Coefficient as well Harrison and Wilson & Schmida beta diversity indices. Once there was lack of spatial autocorrelation (Moran Correlogram), for the floristic similarity calculation we used multivariate statistical analysis. The contemporary vegetation is a confluence between marginal areas of the geographical range of southern grasslands and northern subtropical savannah (Cerrado Domain). There were no evidences of this region as a dispersion center nor corridor between other dispersion centers in the Mata Atlântica Domain. Ecotonal areas lead to biodiversity increase as well point out their extreme vulnerability to climate or anthropogenic disturbances.