Tratamentos silviculturais em clareiras após exploração Florestal

Abstract

The general objective of the work was to evaluate the medium-term effect of post-harvest silvicultural treatments on the survival, growth and structure of commercial species, both from planted trees and those from natural regeneration, both conducted in canopy logging gaps. These gaps were opened in 2004 and 2006, totalling 72 gaps under different types of treatments with assessment over 11 years in the forest management area of the company Jari Florestal SA, located in Monte Dourado, district of the city of Almerim, Eastern Amazon, Brazil. Was evaluated natural regeneration without any silvicultural treatment, so-called standard procedures of reduced impact-logging (SRIL); tending of natural established regeneration (TNER); tending of enrichment planted species with and without prior removal of residues from wood harvesting (EP’s). In the first article, survival and growth were evaluated. The results indicated greater survival and growth of trees with post-harvest silvicultural treatment when compared to the control treatment, which reflects the standard procedures of reduced impact-logging. Legally adopted in Brazil. In the second article, the effect of post-harvest silvicultural treatment for Dinizia excels specie, one of the most important commercial species in the Amazon and which has a low natural density, was evaluated. The survival and growth of D. excelsa trees in different gaps sizes, treatments and crown exposure classes were compared. It was found that there is no difference in the growth of individuals according to the gap sizes, but according to the crown exposure class. Despite the high mortality of planted individuals, they performed better in growth, especially those who received more sunlight. D. excelsa is a species that responds very well, whether for planting or conducting natural regeneration in gaps. The third article sought to evaluate the species Tachigali glauca, also an important commercial species in the Amazon. T. glauca is a specie that responded very well to silvicultural treatment, especially when sunlight is available throughout its crown. It obtained excellent results in survival and growth and this specie is recommended for enrichment planting in gaps. Gaps that have a minimum of 200 m2 are forest spaces with high productivity and /or conservation potential. It is recommended to use these spaces together with the silvicultural treatments for tending both planted individuals and natural regeneration, thus assisting a faster timber production associated with the conservation of commercial species.