Comportamento da regeneração natural das palmeiras em uma floresta tropical sob manejo florestal no município de Moju, Pará.

Abstract

The objective of the present study was to evaluate the dynamics of palms population in a primary forest during 12 years after reduced impact logging. The experiment was carried out in the Experimental Station of Embrapa Eastern Amazon in the municipality of Moju in the State of Para. In a 200 ha sample area, nine gaps caused by logging with size ranging from 231m2 to 748m2 were selected and classified as small, medium and big gaps. Four 10 m x 50m transects were established from the center of each gap to each cardinal direction (north, east, south and west). sub-divided into plots of 10m square side are numbered from 1 to 5 of the edge of the canopy into the forest.Each transect (10m x 50m) was divided in five plots that were numbered from 1 to 5, where individuals with diameter equal or higher than 5cm were measured. Sample plots of 2m x 2m were established in the plots 1, 3 and 5, and in the center of the gap in which the palms natural regeneration (individuals with height equal or higher than 10 cm and diameter lower than 5 cm) were measured. A total of 122 individuals of palms, including young plants (105) and mature plants (17) was sampled. These individuals were distributed among Euterpe oleracea Mart, Oenocarpus bacaba Mart., Attalea maripa (Aubl) Mart., Astrocaryum gynacanthum Mart. and Syagrus inajai (Spruce) Becc. The most common species in the study area was Astrocaryum gynacanthum Mart. Natural regeneration rate (TR%) was calculated using the SAS v.10 software. The evaluation of the behavior of palm trees showed a positive TR throughout the monitoring period. There were significant differences in the East-West direction and in the large clearings, suggesting that the palm species belong to the light-demanding ecological group of species.