This work was carried out at Viçosa (20 º45'S, 42 º07'W) in the Southeastern region of Minas Gerais. The study examed the changes occurred in the stand between surveys done in 1984 and 1998. Species were then classified as pioneers, early secondary and late secondary. Changes in diametric distribution and absolute density were also investigated. Means were compared through student's t and square-chi (chi2) tests. The stand showed to be constituted of nine pioneers, 56 early secondary, and 29 late secondary. Except for Plinia glomerata Berg.) Amshoff and Sorocea bonplandii (Daill.) Burger. Lanjow & Boer, no increase in absolute density could be detected for the individuals from the group of early secondary. The same trend was observed with in the pioneer species, without exceptions. These findings point out a tendency for decreasing importance of these ecological groups. Protium warmingianum March., the only late secondary to be analyzed, showed a significant increase in its absolute density. Overall, these facts suggested an improvement in the conditions of the area for the support of more advanced ecological groups in the successional scale.
ecological succession; semideciduous seasonal forest; ecological groups
