Fitossociologia do estrato arbustivo-arbóreo em gradiente sucessional em área de Caatinga, Baixio-CE.

Abstract

The Caatinga is one of the most degraded ecosystems from an environmental point of view and the least known with regard to the dynamics of vegetation and ecological processes that occur. Aiming at contributing to the knowledge of the structure and composition of the plant community successional gradient Caatinga, this work was developed in backlands depression area in regeneration, located in the community of Sítio Cigano, Baixio-CE. The data collections were carried out in three distance gradients, corresponding to the early, intermediate and late stage phase of ecological succession. They were plotted three fixed plots of 10 x 10 m for each gradient and included all individuals of shrub-arboreal species with CAP (circumference at breast height) ≥ 10 cm and height ≥ 1,5 m. 64 individuals were sampled distributed in four families, five genera and five species for the initial stage; 77 individuals in four families, eight genera and eight species to the intermediate stage; and 49 individuals distributed nine families, 13 genera and 13 species for late stage. Fabaceae was the family with greater wealth and abundance of species in the three gradients. The most abundant species with largest importance value were Croton sp. for the gradient I, Bauhinia cheilantha for the gradient II and Poincianella pyramidalis for the gradient III. The diversity index for the total area H'= 2.069. It was registered a greater diversity to the gradient III. The predominance of initial secondary species in the whole area indicates a slow regeneration.