A flora vascular endêmica do Quadrilátero Ferrífero, Minas Gerais, Brasil: levantamento das espécies e padrões de distribuição geográfica

Abstract

Endemic taxon are those with occurrence restricted to a specific area. The interest in these taxon has been assisting in the development of conservation measures throughout the world. The flora of Brazil, extremely rich, consists of approximately 41.215 species of vascular plants, of which about 18.080 are endemic. In the state of Minas Gerais there are about 2,158 endemic species. The Espinhaço Range, located in Minas Gerais, is classified as a center of endemism. Within the Espinhaço Range, in the far south portion, is inserted the Quadrilátero Ferrífero, a high value mining area that suffers with the increase of local anthropogenic activities in recent years. The Quadrilátero Ferrífero, is classified as a priority area for conservation and the knowledge of its endemic flora emphasizes the importance of conservation. So, the objectives of this study are: to know the endemic flora of the Quadrilátero Ferrífero, to evaluate patterns of endemism richness of the region and model the potential geographical distribution of endemic species. The survey of the endemic species was conducted from bibliography research, botanical collections and gathering in the field. The result is 27 botanic families, 50 gender and 95 species. Of these, 92 are angiosperms, two are monilophytas and only one is a lycophytes. The map of richness generated from the records of the species suggested the existence of 13 areas of endemism in the Quadrilátero Ferrífero. The analysis of floristic similarity between them, using the Jaccard coefficient, showed low similarity, presenting higher level among Itatiaiuçu (IA) and Sabará (SA) (0.50), with three species in common. The Potential Models of Species Distribution were generated by the algorithms Environmental Euclidean Distance, BIOCLIM and MaxEnt. Their results suggested areas potentially richer in endemic species, mainly associated with higher altitudes and therefore with greater interest by mining activities. This study highlights the necessity for conservation measures in the study area, which protects a large number of endemic species, few Units of Integral Protection Conservation and excessive human activities in recent years.