Distribuição vertical da diversidade de epífitas vasculares em uma área de manejo florestal na Amazônia central

Abstract

The diversity, abundance, biomass and vertical stratification of vascular epiphytes were studied in a forest management area of the Precious Woods company. The area is composed of dryland forests of the Ombrophilous Dense type in the region of Itapiranga, Amazonas, Brazil. A total of 118 phorophytes provided by the company at the time of logging were assessed. A total of 22 epiphytic vascular individuals were recorded, represented by the families Orchidaceae (12), Bromeliaceae (5), Araceae (3) and Polypodiaceae (2). The Shannon-Weaver diversity was H' = 2.69. The highest species richness was Orchidaceae, but the relative frequencies of all species were relatively small because of the low abundance of epiphytes in the region. The total fresh mass of epiphytes collected was 4283 grams with the moisture content ranging from 60% to 75%. Principal Component Analysis showed a positive correlation between tree size (DAP and height) and the richness and abundance of epiphytes, with the quantity of phorophytes in diameter classes lower than 40cm being more frequent in the forest. The zones of intermediate vertical stratification from the beginning of the crown to the top showed the highest occurrences of epiphytes in the studied area, showing the best adaptation of these species to microclimatic factors of shading or extreme luminosity.

Keywords: Diversity; phytosociology; epiphytism; biomass, management