Influence of edaphic factors on the floristic composition of an area of cerradão in the brazilian central-west

Abstract

This study describes the influence of edaphic factors on the floristic composition of an area of cerradão (woodland savanna) in the city of Campo Grande, located in the Brazilian central-west. In 10 plots (5 × 20 m each), we evaluated all trees with a diameter at breast height ≥ 4.77 cm. Soil samples were analyzed for each plot in order to determine edaphic variables correlated with species composition. We sampled 1180 individuals of 61 species. The evenness index was 0.74, which indicates uneven distribution of species, which was explained by a high abundance of Qualea parviflora, Curatella americana, Qualea grandiflora, Terminalia argentea and Astronium fraxinifolium. We registered more trees in the smallest diameter class and in the middle layer of the vertical structure. The soil was dystrophic with a clay texture, which explains the higher abundance of species related to dystrophic cerradão. However, we also found some trees typical of mesotrophic cerradão and deciduous forests, which could be attributable to the presence of patches of fertile soil within the dystrophic cerradão or could indicate that those mesotrophic species are tolerant of lower levels of soil nutrients.