Tratamento silvicultural e incremento diamétrico de platonia insignis mart. (clusiaceae) "bacurizeiro" em duas florestas secundárias em bragança, Pa, Brasil

Abstract

The objective of this paper was to describe the effect of silvicultural treatments on diameter increment of Platonia insignis, in two secondary forests, for two years of monitoring (2005/2007). Each forest was denominated of Agrarian Unit (AU) where four plots were installed with 70 m x 105 m (AU1) and 35 m x 100 m (AU2). Two treatments were applied with two replications, T0-no intervention; and T1-silvicultural treatment that consisted of thinning by felling and girdling, crowning of 2 m and cutting of lianas. All P. insignis individuals were measured with DBH > 10 cm. To compare the means, Student t test and Mann Whitney test were used. The average annual increment in diameter in T1 was significantly higher in both secondary forests. AU1 presented 0.14 cm.year-1 for T0 and 0.25 cm.year-1 for T1. In AU2, the average was 0.53 cm.year-1 for T0 and 0.93 cm.year-1 for T1. Therefore, the positive effect of silvicultural treatments in the diameter increase can serve as subsidy for activities of sustainable management and application in secondary forests as growth inductor.