Floristic composition and similarity of a Ferruginous complex within the Iron Quadrangle, Minas Gerais, Brazil

Resumo

Abstract The present study presents species richness for the flora in the ferruginous campo rupestre of the Serra do Pires, located south of the Iron Quadrangle in the state of Minas Gerais, a region under strong threat by mining exploration. The area is composed of a complex of submontane semideciduous seasonal forests and ferruginous fields with distinct vegetation types, where campo limpo and campo sujo are predominant, alongside itabirite boulders and cangas. We found 484 vascular plant species, distributed in 309 genera and 98 families. Eighteen species are endemic to the Iron Quadrangle, and 26 have some endangered status. Herbaceous habit is predominant, found in 257 species (49%), reflecting the expressiveness of ferruginous fields in the area. We also compared the floristic composition of the study area with five other areas with similar vegetation located in the Iron Quadrangle. Similarity analysis revealed a reduced sharing of species between the areas compared. The results point to a complex and unique floristic composition of the Serra do Pires, with many endemic species and taxa still unknown to science, spread over unique environments. Our discussion underlines the inadequacy of the current conservation strategies and suggests the urgent need for more robust and specific public policies for the protection of these environments, considering their high biological diversity and the imminent risk imposed by mining.