Floristic composition and community structure of a seasonally deciduous forest on limestone outcrops in Central Brazil

Abstract

The objective of this study was to analyze the floristic composition and structure of the tree component in a seasonally deciduous forest on limestone outcrops, located in the northeast region of Goias State, Brazil. A sample composed of 25 randomly sampled plots of 20 x 20 m (400 m2) within a 50 ha forest, was measured. All woody individuals > 5 cm diameter at breast height (DBH) had their diameter and height measured. The tree community was composed of 39 species with a density of 734 individuals ha-1; the richest families were Leguminosae (11 species), Bignoniaceae (4 species) and Apocynaceae (4 species). The forest had a basal area of 16.37 m2 ha-1, with the most important species Cavanillesia arborea (3.26 m2 ha-1), Pseudobombax tomentosum (2.35 m2 ha-1), Dilodendron bipinnatum (1.84 m2 ha-1), Tabebuia impetiginosa (1.36 m2 ha-1) and Myracrodruon urundeuva (1.26 m2 ha-1) occupying 61.5% of the total basal area of the forest. Several species grew on rocks, or in rock fissures or in places with a shallow layer of soil or even in litter over rocky layers. The floristic composition showed links with the Caatinga flora, with other patches of seasonal forests in Central Brazil and in the Pantanal, and with the Chiquitano forests of Bolivia too, containing even two species considered as endemic to the Caatinga.