Floristic-structural relationships and functional characteristics of the tree and sapling strata in a rainforest

In secondary forests the identification of plant species and functional groups is an important tool to understand variations in structural parameters of several populations. Hence, the objective of the present study was to describe how the tree and sapling strata are structured in a 47-year old secondary forest, which recovered from agropastoral activities. We defined two strata: the tree stratum, which was defined according to the criterion of a minimum circumference at breast height (CBH) ≥ 15 cm, sampled at 15 10x20-m plots; and the sapling stratum, which comprised all tree species up to 100 cm in height, sampled at 90 1x1-m sub-plots. The results revealed the formation of two floristic-structural groups, separated according to the occupation of the vertical space of the forest. The analysis of functional groups showed that the differences in the proportion of species and individuals between strata were influenced by successional category, dispersal syndrome, and vertical stratification. In general, the floristic-structural pattern observed suggests that the forest fragment is under an intermediate successional stage, and can evolve to a mature forest, as long as the regeneration process is not altered by external factors.