The bulk of a plant hotspot: composition, species richness and conservation status of the Cerrado herbaceous–subshrub flora

Abstract

The Cerrado is a Neotropical savanna with the highest plant species richness among tropical savannas. Most of these species are herbs and subshrubs, although woody species have been studied much more extensively. We built a database of species constituting the herbaceous–subshrub flora of the Cerrado to provide an in-depth view of its conservation status and reduce knowledge gaps. Our objectives were to (1) gather information on the herbaceous–subshrub flora of the Cerrado, (2) determine the importance of the most common families, genera and species making up this flora, (3) map areas with great species richness in the Cerrado, and (4) assess the status of protected areas in relation to this flora and the conservation status of its species. We have created the ‘CerrHerb’ database with information about herbaceous–subshrub species. We identified 6,492 species distributed across 769 genera belonging to 97 families. We compiled 65,535 occurrences of 4,354 species and mapped two main hotspot clusters of species richness: the Central Cerrado and the Espinhaço Range, with a third, less pronounced hotspot cluster further west in the Eastern Mato Grosso. The richest families were the Asteraceae (742 species), Poaceae (681 species) and Fabaceae (584 species). Of the species, 2,398 (55%) occur in protected areas, while 1,956 species (45%) do not. Additionally, 2,235 species are endemic, with no information available on their conservation status. There is a significant knowledge gap regarding the herbaceous–subshrub flora, which can lead to conservation and ecological problems caused by poor management of Cerrado reserves. There is a need to reassess conservation policies for the Cerrado and adapt the management of conservation units to reflect the actual importance of the herbaceous–subshrub flora.