Tree community structure in a Cerrado stricto sensu area, municipality of Porto Nacional, Tocantins, Brazil

Abstract

The present work had the objective of carrying out a survey of the floristic composition and tree diversity on a rural property located in the municipality of Porto Nacional, state of Tocantins, through a forest inventory with simple random sampling. Five 20x50 meter plots were allocated and the height and HCV (>10cm) of the plants were measured. For each sampled species phytosociological parameters regarding frequency, density and dominance were calculated, in addition to the importance value index (IVI), using the FITOPAC program. The similarity between the plots was investigated using the cluster grouping analysis of the R statistical program. The survey resulted in 1,061 individuals, belonging to 35 families and 81 species, among which the most important was Qualea grandiflora, known as pau-terra-da-folha-larga. The Fabaceae family was the most representative with 21 species. The cluster analysis inferred that there is a division into three large groups. One group shows the proximity between areas 1 and 2, the other the similarity between areas 4 and 5, and the last group contains only plot 3, and indicates a greater similarity with plots 4 and 5. The results obtained show the great wealth and diversity of the Cerrado vegetation, demonstrating the real need for more phytosociological studies, so that, based on these, actions can be taken to develop conservationist policies that prioritize the rational use of resources, ensuring the maintenance of this great diversity of plants and environments.