Fitossociologia do estrato lenhoso de uma floresta estacional semidecidual montana na Paraíba, Brasil

Abstract

This study aimed to compare floristic composition and the phytosociological structure between two fragments of stricto sensu cerrado in Grão Mogol, North of Minas Gerais, Brazil. The tree communities were evaluated using the quarter point method. In each fragment, points were distributed equidistant 10 m among them along six transects of 70 m, totaling 48 points per fragment. It was measured, in each point, the height, CBH of four plants to the corresponding quarters in relation to central point. It was considered the individual trees sampled with DHB ≥ 3 cm and height ≥ 1.5 m. It was sampled a total of 73 species in the two fragments, being 48 species in fragment 1, distributed in 41 genera and 24 families, while 54 species were found in fragment 2, distributed in 47 genera and 28 families. The most representative families were Fabaceae and Vochysiaceae. The total density estimated for the fragment 1 was 1275.51 ind. ha-1 and 1580.58 ind. ha-1 to the fragment 2. In both fragments, Qualea parviflora and Eriotheca pubescens showed the highest importance value (IVI). The diversity (H‘) and equability (J) values were 3.13 and 0.87 for fragment 1, and 3.27 and 0.84 for fragment 2, respectively. The Sorensen’s similarity index was 0.68. The diameter and height distribution of the study communities presented inverted-J form, indicating a positive balance between recruitment and mortality, coming from the secondary sucessional process of the communities. The study areas showed woody species richness pattern of the sensu stricto cerrado, however, the area 2 showed higher floristic and structural values, indicating more advanced sucessional stage.