Abstract

ALVARADO, Hipólito  . Structural and floristic aspects of four riparian forests in the Aroa river basin, Yaracuy State, Venezuela. Acta Bot. Venez. [online]. 2008, vol.31, n.1, pp.273-290. ISSN 0084-5906.

Four riparian forests of the basin of the Aroa river neighboring area of the Yuribí National Park in the Aroa mountainous region were studied in western Venezuela, on the purpose of showing the importance of forests in biodiversity conservation. Quantitative data were recorded on the floristic composition, structure and diversity of four 0.1 ha plots. All the individuals with DBH ≥ 2.5 cm were recorded. In this study 789 individuals, 94 species, 78  genera and 38 families of vascular plants were sampled. Among the registered individuals, 40% belong to the families Euphorbiaceae (96 individuals), Piperaceae (53), Annonaceae (38), Mimosaceae (32), Lecythidaceae (31), Myristicaceae (28), Lacistemataceae (23) and Araliaceae (19). The family with the highest number of species was Rubiaceae (10), followed by Euphorbiaceae (7), Mimosaceae (7), Caesalpiniaceae (4), Myristicaceae (4), Araliaceae and Moraceae (3). The riparian forests studied showed an heterogeneous dominance of at least six species, although the riparian forest El Tigre showed a strong dominance of candelo (Gyranthera caribensis) with 19% of Importance Value Index (IVI). The structural characteristics of the studied plots reveal that these riparian forests present a canopy that can reach 8 m of height and that the diametric classes between 2.5 and 10 cm of DBH prevail. However, 49% of the individuals from the riparian forest El Tigre belong to diameter class ≥ 10 cm of DBH and 52% have heights ≥ 8 m.

Keywords : Aroa river; diversity; floristics; riparian forest; Yaracuy; Venezuela.