Composição florística e estrutura do estrato inferior de floresta de várzea estuarina na área de proteção ambiental Ilha do Combu, BelémPA, Brasil.

Abstract

The low layer is formed by the regeneration of tree species, shrub, herbs, lianas and epiphytes forming in ecological niche of vital importance to the establishment and development of the species that will represent ali strata of the forest. In order to analyze the florístic composition and structure of the lower stratum of the lowland forests of the island Combu, city of Belém-PA, were arranged alternately on a sytematic 50 plots of 50 x 4m, and divided into 25 plots of 2 x 2m. Have been identified, quantified and estimated the percentage of coverage of the species based on height and or in diameter at breast height (DBH) ^ lOcm. It was calculated to sample sufficiency, diversity, density, frequency, rate of natural regeneration, cluster analysis, analysis of the species, amount of coverage and the index value of coverage. Trough analysis of the sample sufficiency noted that the subplots were sufficient to represent the florístic composition, showing good representation of wealth. We found 67 families, 160 generas, 223 species; Euterpe oleracea, Virola surinamensis, Inga alba, Inga edulis e Symphonia globulifera, showed the highest rates of natural regeneration (RN%), and Pariana radiciflora e Philodendron sp. The highest rates of IVC%. It was observed that about 40% of the species accurred in ali size classes, 35% in two and 25% in just one. The species of tree habit had more individuais, followed by the authorities, herbaceous, shrubby, hemiepiphytes and epiphytes. The cluster analysis separated the community with distinction in nine groups, and the analysis of species, from 223 species recorded, six were highly significant, 21 major and 196 non-significant. The florístic composition showed the dominance of a few species with a large number of individuais, the diversity was relatively high, few species were considered as indicators.