Floristic and structure of the arboreal community of an Ombrophilous Dense Forest at 800 m above sea level, in Ubatuba/SP, Brazil

Ana Cláudia Oliveira De Souza,Luís Benacci,Carlos Alfredo Joly

doi:10.1590/1676-0611-bn-2018-0590

Abstract

Abstract: Undoubtedly, the publication of floristic lists and phytosociological studies are important tools for metadata generation, quantification and characterization of the megadiversity of Brazilian forests. In this sense, this work had the objective of describing the composition and the structure of the tree community of one hectare of Dense Atlantic Rainforest, at an altitude of 800 m. All individuals, including trees, palm trees, arborescent ferns and dead and standing stems, with a diameter at breast height (DBH) of ≥ 4.8 cm were sampled. After the identification of the botanical material, we proceeded to calculate the usual phytosociological parameters, besides the Shannon diversity index (H') and Pielou equability index (J). A total of 1.791 individuals were sampled, of which 1.729 were alive, belonging to 185 species, 100 genera and 46 families. The results obtained showed a strong similarity of structure and floristic composition with plots of both Montana and Sub Montana Ombrophilous Dense Forest studied in the same region. This reinforces the hypothesis that the transition between the phytophysiognomies of the Atlantic Ombrophylous Dense Forest is gradual, and that the boundaries between them cannot be clearly established.

Highlights

The Atlantic Forest, classified by Myers et al (2000) among the five most threatened hotspots in the world, originally covered about 82% of the state of São Paulo (Joly et al 1999), especially due to the coffee economic cycle, was reduced to about 5% of its original area (Kronka et al 2005)
The three richest families at 800 m (Myrtaceae, Rubiaceae and Fabaceae) were the same as those observed by Ramos et al (2011) and Gomes et al (2011) in stretches of Sub Montana Ombrophilous Dense Forest, respective to those of 200 and 350 m of altitude, located in the same region
In another area of the same region (350 m of altitude), Lauraceae occupied the second position among the richest families (Rochelle et al 2011), as in the Montana Ombrophilous Dense (Montane) Forest (Padgurschi et al 2011 - 1000 m altitude)

Summary

Introduction

The Atlantic Forest, classified by Myers et al (2000) among the five most threatened hotspots in the world, originally covered about 82% of the state of São Paulo (Joly et al 1999), especially due to the coffee economic cycle, was reduced to about 5% of its original area (Kronka et al 2005). This biome, which is classified as the second largest tropical rainforest on the American continent (Morellato & Haddad 2000), is composed of a mosaic of ecosystems with specific ecological processes (Campanili & Schaffer 2010). Between the elevations of 400 and 1000 m altitude, a large information gap persisted, because there was no floristic or phytosociological study with expressive representativeness of the arboreal vegetation in these intermediate levels

Methods

Results

Conclusion