High floristic richness revealed in grasslands of quartzitic hills in Southern Brazil

Resumen

Abstract Southern Brazilian highland grasslands harbor a highly diverse and unique flora, a result of millions of years of local adaptations. These grasslands are drastically threatened by land-use conversion, biological invasion, modified disturbance regime and overgrazing. The grasslands of the First Paraná Plateau are one of the three priority areas for conservation in Southern Brazilian highlands, thanks to their exceptional diversity and endemism. Nevertheless, they remain poorly documented and largely neglected by conservation policies. Seeking to expand knowledge about these grasslands, we carried out a floristic survey, similarity analysis and characterization of vegetation physiognomies, within highland grassland remnants of quartzitic hills, situated in the metropolitan region of Curitiba, State of Paraná, Southern Brazil. Six grasslands were selected for the similarity analysis: one from Pampa biome, one from Cerrado biome, and the others associated with Atlantic Forest biome. We recorded 493 taxa (478 native) in three physiognomies: herbaceous, shrubby and rocky grassland. Significant records were obtained, including threatened and very rare taxa, in addition to a new species of Iridaceae. Little similarity was found between evaluated sites, and 145 taxa (31%), including five threatened, were recorded exclusively in our study. We hope our study improves the database for further research into highland grasslands, as well as contributes to conservation and management strategies.