Structure and Successional Classification of the Shrub-Arboreal Component in a Remnant of Atlantic Forest, Northeastern Brazil

Abstract

Aims: We aimed to evaluate the structure and successional classification of component shrub-arboreal in the edge and interior environments in a remnant of Tropical Forest in Pernambuco, Brazil.
 Place and Duration of Study: The study was conducted in a remnant of the Lowland Ombrophilous Dense Forest categorized as Urban Forest Reserve named Mata of Manassu, with an area approximately 264.24 ha and located in Jaboatao dos Guararapes, Pernambuco. The data were registered between March 2017 and September 2017.
 Methodology: The data were collected in 40 100 m2 plots, 20 plots in each environment: edge and forest interior. The ‘‘edge’’ was considered to comprise a 100-m strip at the border of the forest and the ‘‘interior’’ at least 300 m in from this strip. In all plots, were cataloged, identified and measured the circumferences at height of the base at 30 cm from the soil of all shrub-arboreal individuals whose height were equal or greater than 1.0 meter and circumference at breast height at 1.30 m of soil, less than 15.0 cm. For the communities on the edge and forest interior were estimated: total density (TD), absolute density (AD), relative density (RD), total frequency (TF), absolute frequency (AF), relative frequency (RF), total dominance (TDo), absolute dominance (ADo), relative dominance (RDo), relative natural regeneration by height class (RNRij), total natural regeneration by height class (TNR), importance value index (IVI) and was performed the distribution analysis of individuals in three height classes using the Chi-square test with 95% significance. The sampled individuals were classified into family, genus, and species, and the species classified for the successional group (pioneers, initial secondary, late secondary or uncharacterized).
 Results: The environment of the edge showed the highest absolute density (10.240 ind.haˉ¹) to the forest interior (9.805 ind.haˉ¹). In both environments, it was found the high representativity of initial and late secondary species. The structural distributions of individuals by height class at the edge and interior environments showed curves shaped as inverted "J" indicating "dynamic balance" of the forest.
 Conclusion: The higher representativity of initial and late secondary species probably is due to the forest being in an advanced successional stage, having a structure with well-defined stratum. Among the shrub-arboreal species sampled which presented higher total natural regeneration per height class to both in the edge and forest interior and that can be used for the enrichment of areas in the recovery process of Atlantic Forest are Miconia prasina e Eschweilera ovata.