Caracterização da madeira e estoque de carbono em genótipos de Eucalyptus cultivados em sistema agrossilvipastoril no cerrado brasileiro

Abstract

This study aimed to characterize wood quality and carbon stocks in two Eucalyptus genotypes (E. cloeziana and E. urograndis) in an agroforestry system in the Brazilian Cerrado. To characterize the wood, discs were removed at positions of 2%, 10%, 30%, 50%, 70% of the commercial height, in addition to the diameter at the chest height of the eucalyptus trees. Rigorous cubing was carried out through continuous inventories and assessment of diameter distribution. There was no proportional relationship between diameter growth and shell thickness. E. urograndis showed better growth performance in diameter and height, producing lower shell content, as well as greater medullary eccentricity in all diameter classes and disc positions. Both genotypes showed a high heartwood/sapwood ratio, indicating high quality wood for sawmills purposes. E. urograndis and E. cloeziana presented wood density values of 0.637 and 0.724 g/cm³, respectively. The highest carbon stocks in wood were observed in E. urograndis, with average values of 62.90 Mg ha-¹. Our results showed that E. urograndis performed better when compared to E. cloeziana, being the most suitable genotype for sawmill purposes and to promote carbon sequestration in agroforestry systems in the Brazilian Cerrado.