DIAMETER STRUCTURE AND PHYTOSOCIOLOGICAL FREQUENCY OF A “TERRA FIRME ” AMAZON FOREST, BEFORE AND AFTER SELECTIVE CUTTING

This article aims to characterize horizontal and diameter structure of a managed forest using graphic expression techniques. Data for this research is result of complete forest inventory (census) carried out from a block of 800 hectares, before and after selective cutting, inside Tapajós National Forest, located in the Municipality of Belterra, State of Pará, Brazil. The analysis revealed that, in relation to horizontal structure, intense cutting resulted in changes of different levels mainly to phytosociological frequency of some species, such as, Manilkara huberi, Carapa guianensis and Tabebuia serratifolia. The diameter structure of some species, such as Sextonia rubra and Dipteryx odorata, revealed changes after selective cutting under technically acceptable rates, because the stock levels of some diameter classes surpassed the limits of balance observed for polycyclic systems with silviculture based on natural regeneration. The inclusion of graphics in the harvest operating plan for the 10 most important species listed in forest management, that is, before and after selective cutting, would lead to the desirable structure maintenance