Dinâmica de Eschweilera amazonica R. Knuth (Matamata-CI) em uma área de floresta de terra firme na Amazônia Oriental.

Abstract

Eschweilera amazonica R. Knuth is a species with high potential for commercialization. However, little used due to lack of knowledge about its population. In order to improve the knowledge of the species, the dynamics of E. amazonica was evaluated in an experimental area at km 114 of the BR 163, Tapajós National Forest (03º 18'32'' S - 03º 19' 21'' S and 54º 56 ' 28'' W - 54º 56' 15'' W), where logging and silvicultural treatments were carried out. Data were collected in 60 permanent plots of 0.25 ha located in logged and unlogged areas, over a 31-year period. During this period, the population structure of the species, mortality, recruitment and growth rates of individuals with DBH ≥ 5.0 cm were evaluated. The results of the study revealed that the species presents a J-reverse diameter distribution that was not altered by the logging, although it was not balanced, according to De Liocourt's "q" quotient. Logging did not significantly affect the population structure, with a density of 11.08 ind. ha-1 after 31 years of monitoring. On the other hand, the species does not exceed the minimum cut diameter of 50 cm as established by current legislation. Thus, for the species to be harvested, special approval from the environmental licensing agency is required for its extraction. E. amazonica showed stability between mortality and recruitment, however with the highest mortality rate (6.1% year-1 ) right after logging, which may be due not only to the removal of wood, but also to the damage caused by the activity in remaining vegetation. The diameter increment was significant only at seven years after logging, remaining similar between the logged and unlogged area in the other periods. It is concluded that the species does not need large gaps for establishment and growth, however it benefits from the opening of the forest canopy, confirming the ecological nature of shade-tolerant species.