Size, Ecology, and Seasonality Affect the Monthly Diametric Growth of Trees in a Secondary Forest

This work aimed to evaluate the monthly growth rate of 100 trees spread in different diametric classes and ecological groups of a secondary forest in the municipality of Igarapé-Açu, Pará, Brazil. These were selected randomly from 30 permanent plots and classified into 5 diametrical classes and separated into two ecological groups: Pioneers and Non-Pioneers. The monthly periodic increment (MPI) in diameter was measured for 11 months by means of diametric bands using digital calipers. The MPI means were evaluated by an analysis of variance (ANOVA) and Tukey’s mean comparison test. Individuals from both ecological groups had similar increments in the DBH IV diameter class and different in the others. There were mean increments in the diametric classes that did not differ within the ecological groups. The trees analyzed differed in the diametric growth rate according to the diametric classes, ecological groups and the month of analysis.