Dinâmica de uma floresta de terra firme, durante 12 anos de avaliação após exploração de impacto reduzido, no município de Moju, Pará.

Abstract

The knowledge of dynamics on floristic composition and forest structural levels is extremely important to make a better planning of logging activities aiming sustainable timber production. Thus, in the present study the dynamics of floristic composition and forest structure of a forest logged applying reduced impact techniques were evaluate. Also, the recovery of logged species was evaluated during a 12-year-period. The plots were selected starting in gaps caused by logging. In each gap 10x50 m plots were installed, starting in the gap’s edge going into the forest, in north, south, east and west directions. Individuals were divided in two strata: I (DAP < 5 cm; H ≥ 10 cm) and II (DAP ≥ 5 cm). Individuals from stratum II were measured in the 10x50 m plots that have been divided into five 10x10 m plots. Individuals from stratum I were measured in 2x2m plots allocated at the beginning of the plots 1, 3 and 5 in each plot, and in the center of each gap. Strata I and II had a significant difference in their total abundance in each measurement (p = 0.000). Abundance of logged species decreased over the study period, while the mortality rate increased in the end of the period, as well as the recruitment rate reduced during the study period. Floristic diversity remained stable, but with few changes over the 12-year-period, however, with significant changes in the number of individuals. Inthis way, it is necessary to apply the right techniques into the species of commercial interest for having successiving logging, in order to facilitate the growth of individuals of the these species on field. Logged species individuals founded difficulty for stabilization, with increase in mortality rates, therefore activities are needed to benefit these individuals, in order to recover the removed stock.