Ecología en Bolivia
versão impressa ISSN 1605-2528
VILLARROEL, Daniel et al. Structure, composition and tree diversity of two areas in the Cerrado sensu stricto in the Chiquitanía (Santa Cruz, Bolivia). Ecología en Bolivia [online]. 2010, vol.45, n.2, pp. 116-130. ISSN 1605-2528.
We studied two areas of the Cerrado sensu stricto, middle (Cacarachi) and south (Tucavaca) of Chiquitanía (western Bolivia), in order of compare the structure, composition and tree diversity. To this end, we installed a permanent sample plot of 1 ha for each area, registering all individuals ≥ 10 cm dbh. We analyzed the frequency, abundance, dominance and Importance Value Index by families and species. Diversity was calculated using the Shannon Wiener and Simpson index, and estimated species richness with models of CHAO 2 and BOOTSTRAP. The qualitative and quantitative similarity was calculated with the Jaccard and Sørensen index. The results indicated that families with more IVF in Cacarachi are Dilleniaceae, Anacardiaceae and Fabaceae, and Sapindaceae, while in Tucavaca are Bignoniaceae and Oleaceae. The species with the highest IVI in Cacarachi are Curatella americana and Astronium fraxinifolium, and in Tucavaca: Magonia pubescens, Tabebuia aurea, Linociera hassleriana and Astronium fraxinifolium, these two groups of species represent more than 70% of the total IVI of their respective areas, to be decisive for determining physiognomy in each vegetal community. In Cacarachi, the distribution of individuals per diameter class was normal and equilibrated, while in Tucavaca it was disproportionate, possibly due to annual burning to which it is subjected. The richness estimates indicated that there was more than 80% of species calculated for 1 ha for each site, with Tucavaca being the most diverse (H ‘= 1.8, λ = 4.3).
Palavras-chave : Cerrado sensu stricto; Chiquitania; Composition; Diversity; Structure.