Floristic and structural characterization of forest communities in different physiographic units, El Dorado - Tumeremo, Bolívar – Venezuela

The objective of this work was to identify forest communities in the different physiographic units in the El Dorado-Tumeremo Forest, to evaluate its structure and its floristic composition. Nine 1 ha plots (three for each forest type) were selected and established according to a restricted random design. In each plot, all individuals of tree species with diameter at breast height (DBH ≥ 10 cm) were measured. Several diversity indexes were used to estimate the alpha and beta diversities, as well as the Importance Value Index (IVI). A cluster analysis was carried out to find out if there were floristic similitudes among the forest types. 5462 individuals were surveyed, 38 families, 77 genera and 95 species. The highest values of Fisher alpha (17,77), Shannon (3,44) and Simpson (0,95) index. The average forest density was 606 ind/ha The family Fabaceae was the most represented. In all physiographic units were identified Lepidocordia punctata, Peltogyne venosa and Spondias mombin. Comments about floristic and ecological aspects are included, and information where these species were found is also presented.