Composição florística de florestas em diferentes estágios de regeneração no Rio Grande do Sul.

This study aimed to describe and compare the floristic composition and structure of tree and shrub vegetation, as well as identifying trends in the dynamics of species in forest fragments with different stages of regeneration. An inventory was conducted in the forest fragments, adopting the method of systematic sampling with sampling units (SUs) of fixed area, with dimensions of 20 x 10 m, distributed throughout the area. 23 SUs were allocated in the secondary forest fragment and 10 SUs in the capoeira fragment, which was held the vegetation survey three classes of inclusion: R1 (seedlings regeneration): h and ≥ 50cm DBH < 2 cm; R2 (established regeneration): DBH between 2 and 5 cm, and A (arboreal stratum): DBH ≥ 5 cm. 87 species were found belonging to 36 families. The floristic composition was similar in the arboreal stratum, showing Lithrea molleoides as the species most important in both fragments. The natural regeneration of forest was characterized by Psychotria leiocarpa and regeneration of capoeira by Myrcia oblongata. The differences observed between forests showed trends of changes in the woody component according to the natural dynamics of the species in the process of secondary succession. [ABSTRACT FROM AUTHOR]