Ecologia de ep?fitas vasculares em uma ?rea de Mata Atl?ntica do Parque Nacional da Serra dos ?rg?os, Teres?polis, RJ

• Autor(a) principal: Dias, Aline dos Santos
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/tede/476
• topic: ecologia do epifitismo; intera??o entre plantas; distribui??o espacial; Parque Nacional da Serra dos ?rg?os; Mata Montana; epiphytic ecology; plant interaction; spatial distribution; Serra dos ?rg?os National Park; montana forest; Ecologia

?The epiphytes are plants that use trees as support without being connected to the ground. The epiphytes have wide geographical distribution and could be finding basically in most tropical rain forest, representing 50% of the neotropical vascular flora. The families more representative are Orchidaceae, Bromeliaceae, Araceae and Polypodiaceae. Despite the increase in the number of studies on the epiphytism in Brazil, information on this guild in the remaining forests of Rio de Janeiro state are still scarce. Thus, this study aimed to analyze the composition, richness and guild structure on a forest situated between 500 and 1500 meters over sea level (montana forest) in the Serra do ?rg?os National Park (RJ). In the 60 plots of 100 m2 (0.6 ha), all trees with DBH > 10.0 cm had their diameter and total height measured. All epiphytes were identified and their abundances were estimated for each class of height stipulated for the host trees. The relative frequencies of occurrence of species were calculated for the area as a whole and for host trees as well as for the host trees classes of height, canopy and trunk, and your value of importance calculated. Each species was classified according to their ecological category. The horizontal distribution of species was analyzed using the Morisita index and vertical by ?2 test. Relationship between the morphometric characteristics of host trees and richness and abundance of epiphytes were performed by simple regression analysis. We identified 84 species of epiphytes, in 28 genera and 9 families. The most representative families were Bromeliaceae, Araceae and Polypodicaeae. In this area, the epiphytes richness is considered high when compared with several studies in Brazil. The most frequent species were Microgramma squamulosa, Pleopeltis pleopeltifolia and P. hirsutissimum and a high number were considered rare species. Pleopeltis pleopeltifolia was more frequent in host trees, followed by P. hirsutissimum and M. squamulosa. These species also occurred in high frequencies in other studies, showing its wide geographical distribution and its importance in the composition of this guild. The species with higher importance are epiphytics P. hirsutissimum, P. pleopeltifolia and M. squamulosa, showing the high capacity of these species to occupy the host trees. Most epiphytes in this area (56% of species) are classified as holoepiphytes, as shown in other similar studies. For the horizontal distribution, random distribution pattern were observed for basically all high abundance epiphytes, indicating that this area has a wide availability of resources for the establishment of these species. In vertical distribution, we observed a significant difference in the occupation of the different classes of height of host trees for 53 of 84 species sampled. The highest occurrence of epiphytes was observed in the canopy. There were significant and positive relationship between height and total host trees with the richness and abundance of epiphytes, as well as between DBH and richness and abundance of epiphytes. Thus, the epiphytes respond directly to the structure of the forest where they are found, varying its parameters under different ecological characteristics with structure of forest formation.