Dinâmica de uma Floresta Atlântica Semidecídua

Abstract

The present study aimed to analyze if the dynamics confirms the influence of environmental heterogeneity in the structure of the tree component, in an area of Semideciduous Atlantic Forest in Parque Ecológico Quedas do Rio Bonito, Lavras, southern of Minas Gerais state. The study was conducted in two transects sampled placed in 26 and 38 plots, respectively, of 10m x 30m. The transect B was inventoried in 2000, 2005 and 2011, and C in 2001, 2006 and 2011. In both forest sections (transects B and C) predominated among the 10 most abundant species, but also between species of low abundance who entered and left the community, the presence of climax trees (shade-tolerant and light demanding), which is indicative of advanced successional stage. The advancement of succession was also indicated by the thinning trend of smaller individuals (5 to 10 cm in diameter), and regeneration of individuals greater than 10 cm for the 10 most abundant species in both transects. However, transection C showed a greater growth of trees greater than 10cm diameter. The average annual rates of mortality, recruitment, net change in density and basal area, and rates of gain in basal area in transect B demonstrated for the two intervals analyzed (2000 to 2005 and 2005 to 2011) that this part of the forest is advancing in succession, which is characterized by thinning out the tree component, especially for smaller trees. The thinning out is characterized by reducing the number of individuals and increased basal area. Turnover rates in basal area for both transects that there is a rapid accumulation of biomass. In transect C in the interval from 2001 to 2006 his patch of forest analysis showed that passed through a stage of equilibrium, characterized by the simultaneous increase of basal area and number of individuals. However, in the range of 2006 to 2011, the tree component in C transect showed a transition to a regeneration process after thinning of the trees. The results of this study showed that the heterogeneity of the two parts of the rainforest is probably the main factor that influences the dynamic tree, forming distinct forest mosaics over the time