Avaliações físico-químicas, anatômicas e energéticas do lenho das espécies Poincianella pyramidalis Tul.L.P. Queiroz e Handroanthus impertiginosus (Mart. ex DC.) Mattos. de ocorrência no Semiárido Brasileiro.

Abstract

The native vegetation of Northeast Brazil has been explored and used intensively and inadequately as a source of energy and material for rural constructions. Now, it is recognized how important it is to know the characteristic of the wood produced by this vegetation. Thus, this study provides information on the physicochemical, anatomical and energetic characteristics of Poincianella pyramidalis Tul. L.P.Queiroz and Handroanthus impertiginosus (Mart. ex DC.) Mattos wood, so that these species can be better used and protected. Thirty cm sections were removed from each tree at 0 (base), 25, 50, 75 and 100% height of the commercial trunk (trunk diameter > 5 cm). A 2.5 cm thick disc was removed from the median part of each 30 cm section, and each disc was subdivided in four wedge pieces passing through the trunk pith. The first and third wedge pieces were used to determine the basic density of wood, ant the other two pieces to collect data on wood anatomy and chemistry. In general, the wood of these two species showed similar anatomical and physical characteristics. Handroanthus impertiginosus wood showed a higher lignin content, and no significant difference among species was detected for holocellulose content. Poincianella pyramidalis wood and charcoal showed lower values to the superior calorific power. Handroanthus impertiginosus charcoal had the highest fixed carbon content. These species showed similar charcoal true density and fixed carbon production. For Poincianella pyramidalis, the gravimetric yield showed positive significant correlations with the total extractive content and fixed carbon production, and negative significant correlation with charcoal true density. For Handroanthus impertiginosus, the total lignin content correlated positive and significantly with the calorific value of wood, and negative and significantly with the holocellulose content. The basic wood density had significant and negative correlations with fiber lumen diameter and fiber width. Handroanthus impertiginosus showed the best properties for energy use.