Is the rock cover a good predictor of the variations in species richness and structure of the arboreal and shrubby vegetation in Cerrado Rupestre areas?

Abstract

Rocky outcrops are regarded as limiting factors for plant establishment in rupestrian environments. In this study, we tested whether the rock cover is associated with variations in species richness and density, height, and diameter of trees and shrubs in six Cerrado Rupestre sites in Central Brazil. On each site, we sampled vegetation and visually estimated the rock cover in ten 20 × 50 m plots divided in 10 × 10 m subplots. We analyzed the association between the rock cover and vegetation parameters by Spearman correlation. The number of individuals and mean plant height were negatively associated with the rock cover, but these associations were weak (rs ~ -0.1). Neither species richness nor mean plant diameter were associated with the rock cover. We concluded that the rock cover is a good predictor of variations in neither species richness nor structure of the arboreal and shrubby vegetation on Cerrado Rupestre areas in Central Brazil.