Diagnóstico madeireiro de três mesorregiões do Estado da Paraíba.

Abstract

The work was carried out in three mesoregions (Sertao, Borborema, and Agreste) of the State of Paraiba and aimed to survey and identifies the wood potential of native species of the Brazilian Semi-Arid region to be used in rural building. These objectives were pursued to contribute, through detailed analyses of Diametrical Classes, for implementation of sustainable exploitation forms to optimise the efficient cutting of logs and valuation of forestry products and sub-products to be used in rural building. Forestry inventory records were carried out at five study areas, which were systematically sampled, being surveyed 102 plots of 400 m2 (20 x 20 m), at five rural properties situated in the municipalities of Sousa, Itaporanga, Sao Mamede, Sao Jose dos Cordeiros, and Caicara. The form factor used for calculating the real volume was 0.9; and the piled up volume was used 3.41. The trees were categorized according to their DBHs (diameter at breast height) comprising ranges of four classes, in order to evaluate the diametrical distribution and the quantification of sub-products to be used in rural buildings. Only the individuals with DBII > 2 cm were included in the inventory record. The DBH was measured and for all plants of this record, carried out at 1.30 m above ground and the diameter in the tree base at 0.30 m above the ground. The sampling areas 1 and 2 presented 84.48% and 86.23%, respectively, of individuals with immediate utilization potential only in Classes I and I I . The Diametrical Classes analyse by species indicated a quite reasonable occurrence of species that are widely used in buildings, with some possibility to reach Classes III and IV in a few years i f they are well preserved or utilized through selective forestry management. The most satisfactory results were obtained from the areas 2 and 3 with respect to volume per area and to volumetric percentage and species diversity to be used in buildings. High percentages of dead trees were generally observed, except in area 1.