Avaliação da madeira de espécies exóticas invasoras em Unidade de Conservação

Abstract

Invasive trees species proliferate without control and cause several problems to the local biota. This fact decreases the species richness index, causing a threat to biodiversity and the balance of ecosystems in Conservation Units. To reverse this situation, it is necessary to remove these trees from protected areas, an expensive and difficult process. It is importance to restore the balance of the ecosystem and remove these trees. However, after their removal, an outbreak or impasse regarding the destruction of this material. The lack of knowledge about the characteristics of the wood makes it difficult to indicate more appropriate uses, which makes the added value of the material lower. The study of these properties made to show an alternative raw material for the wood sector is essential. General objective was to subsidize alternatives for the use of invasive species, by assessing their properties and indicating their potential for the timber sector. Three invasive species of the Atlantic Forest were studied: Artocarpus heterophyllus Lamarck (Jackfruit), Syzygium cumini (L.) Skeels (Java plum) and Clitoria fairchildiana R.A. Howard (Sombreiro). The study started with the dendrometric characteristics of the trees (diameter and commercial height). The trees were felled, as the logs were evaluated for the quality of their shape and the yield of the breakdown was determined. After the breakdown of the logs, the drying schedule was developed by species. The physical, chemical, mechanical and anatomical properties of the wood were evaluated and differences in the pith-bark direction were verified. The quality of the machined surface was also analyzed, in addition to its relationship with wood resources, allowing the manufacture of furniture. The invasive species evaluated have good quality logs, with satisfactory breakdown performance, characteristics favorable for use as sawn wood. Regarding drying, the analyzed woods showed a low tendency to warp and a moderate incidence of top and surface cracks, in addition to not having collapse, the three species can be plowed in a single drying schedule. Java plum wood has adequate mechanical strength for use in civil construction such as beams, rafters and fences. The Jackfruit and Java plum wood showed good workability, satisfactory surface quality and low contractions, which make them suitable for products with greater added value, such as furniture, frames, ceilings, in addition to presenting adequate hardness to be used with floors. Among the three species studied, Sombreiro wood showed the least mechanical resistance and surface quality (regular), limiting the use of wood to products of lower added value for temporary use, such as concrete forms used in civil construction. It was found that several wood products can be generated from the woody material of invasive species. Thus, this material cannot be seen as waste, but as an alternative raw material for timber purposes.