STRUCTURE AND DYNAMICS OF THE SHRUBBY-ARBOREOUS COMPONENT IN A SEASONALLY DRY TROPICAL FOREST UNDER FOREST MANAGEMENT, IN MACAU, RN
cutting cycle; natural regeneration; phytosociology
Considering the importance of evaluating the compatibility between the exploitation system usually used in the Caatinga and the vegetation regeneration process, identifying the growth dynamics and investigating the loss of floristic diversity, this study aims to characterize the adult and regenerative shrub-tree component, in four stands with ages of 9-, 12-, 16-, 20- and 26-years post-exploitation, submitted to clear and selective cutting regimes. For the adult component, individuals with CAP ≥ 6 cm and total height greater than 1.0 m were measured, in permanent plots of 20 x 20 m, and subplots of 5 x 5 m were used to evaluate the regenerative stratum, measuring the individuals with total height greater than 0.5 m and CAP < 6.0 cm. Data analysis was performed by estimating phytosociological parameters (absolute and relative), such as: frequency, density and dominance, as well as the importance value index, diversity index, basal area and volumetry. Ten species were inventoried, distributed in four families, among them, the following stand out: Croton blanchetianus, Pityrocarpa moniliformis, Cenostigma pyramidale and Piptadenia retusa, due to their high density. Data analysis made it possible to observe a distinction between treatments, especially in the structural parameters of density (CS3 – 1,867 ind ha-1; CS1 – 1,742 ind ha-1; CS2 – 1,575 ind ha-1; CR – 1,550 ind ha-1), dominance (CS3 – 5.05 m² ha-1; CS2 – 4.51 m² ha-1; CR – 4.17 m² ha-1; CS1 – 3.45 m² ha-1), vertical stratification and forest dynamics. Management systems CS2 and CS3 stood out in relation to CR and CS1 in terms of the recovery of the original stock in basal area and volume, presenting values higher than those of 1995 and indicating that the initial data did not correspond to the maximum potential for woody biomass. The forest dynamics of the evaluated area points to the insufficiency of the 15-year cutting cycle, common in PMFS in Rio Grande do Norte, regarding the recovery of forest composition and structure in this region.