Challenges of the lumber production in the Amazon region: relation between sustainability of sawmills, process yield and logs quality

There has been an increasing global demand for more sustainable production systems, especially in what concerns goods produced from natural tropical forests. The lumber industry in the Brazilian Amazon region produces a significant volume of lumber, and as a consequence of frequent non-optimal procedures, considerable amounts of waste are generated. In order to optimize the timber production and to minimize the environmental damage associated with low yields of sawmills, two features are indispensable: the lumber yield and the quality of the logs. The aim of this research was to analyze the wood quality and lumber yield of logs of tree species harvested from natural stands in the Amazon rainforest. A total of 120 logs from 21 tree species were harvested from natural stands in the state of Para, Brazil, and analyzed for wood quality. Out of these, 60 logs were evaluated for lumber yield. The most common defects found in the logs were flattening, surface cracks, and eccentricity of the pith. By means of the principal component analysis, the Mezilaurus itauba, Protium decandrum, and Caryocar villosum species stood out. The average lumber yield was 45%. The Bowdichia nitida and C. villosum species presented the highest yield values (average of 63%). There was a trend of correlation between the lumber yield and the quality of the logs. Based on the methodology used to analyze the quality of the logs, inferences can be made on the yield of the logging and, consequently, the sustainability of the timber industries in the Brazilian Amazon.