This study was developed in the Mata do Paraíso Reserve from the Viçosa Federal University. Ten natural gaps of different sizes were selected. Digital hemispherical photographs were obtained from the middle of the gaps, in a 5 m understorey area (surroundings) and neighboring areas. These hemispherical photographs allowed calculating areas corresponding to gaps and their respective canopy openness and surroundings. Inside the gaps and surroundings, all individuals with height > 1.00 m and diameter in height of 1.30 m from the soil (DAP) below 5.00 m were sampled. The predominance of small gaps with areas below 100 m2 and with small canopy openness was verified, as well as the predominance of the same shade-tolerant species typical of the final succession stadiums, which are abundant in the understorey around these gaps. In the set of gaps, 759 individuals were sampled and distributed into 69 species belonging to 28 botanical families. The Shannon diversity index (H') of gaps ranged from 1.026 to 3.011. Coffea arabica and Picramnia regnelli were the most abundant species both in the set of gaps and in the set of surroundings (understorey). The floristic similarity between both sets was high (Ij = 69%), indicating that the same species that regenerate in the sub-wood also regenerate in the gaps environment. At long term, the ecological dominance of Coffea arabica in both environments may impair the conservation of autoctone species in this part of the forest.
Gaps; forest canopy; understorey; Semideciduous Forest
