Padrão espacial de espécies arbóreas em fragmento de floresta estacional semidecidual

Abstract

Knowing the spatial distribution of forest species is important for understanding ecological processes in a given community. The aim of this study was to analyze the spatial distribution of four higher density species in a semidecidual seasonal forest fragment. Data of diameter at breast height (DBH), total height, and the geographical coordinates of all individual trees with DBH ≥ 10 cm were collected. The coordinates of the four most common species, taking into account the absolute density, were integrated into a geographic information system program (GIS) and the spatial distribution pattern was analyzed by Ripley’s K function in its univariate form. The relationship between pairs of events every 5 m up to a distance of 60 m was evaluated. The construction of confidence envelopes was performed using 499 Monte Carlo simulations. The four species of higher density in descending order were Callisthene major, Acrocomia aculeata, Luehea divaricata and Tapirira guianensis. The spatial patterns detected were completely random for Tapirira guianensis and aggregate for Acrocomia aculeata and Luehea divaricata. The species Callisthene major presented varied spatial pattern depending on the distance considered. Furthermore, differences on the spatial pattern of individuals of the same species were observed when these were separated into diametric groups; those with DBH ≤ 30 cm presented random pattern and those with DBH > 30 cm showed aggregate pattern. This indicates that older individuals grow singly in the forest.