Evaluation on paper making potential of nine Eucalyptus species based on wood anatomical features.

摘要

Eucalypt wood is known worldwide as a raw-material for pulping but only a few species are used by the industry. One of the important features for pulping is the wood structure and anatomy, including cell biometry and cell type proportion. This work makes a prospective study of nine eucalypt species aiming at a pulping use by an early assessment of wood anatomical features. Young 50-month-old trees grown in the same environment of Eucalyptus camaldulensis, Eucalyptus globulus, Eucalyptus maculata, Eucalyptus melliodora, Eucalyptus ovata, Eucalyptus propinqua, Eucalyptus sideroxylon, Eucalyptus tereticornis and Eucalyptus viminalis were studied in relation to wood anatomy, cell biometry and proportion, and morphological fibre ratios. The nine species are structurally similar with typical eucalypt wood features, e.g. diffuse porosity with predominantly solitary vessels and simple perforations plates, and most anatomical differences between species related to rays and axial parenchyma. The wood is in general uniform and the radial variation of cellular dimensions is of small magnitude. The species showed a higher diversity regarding proportion of fibres (15-50%) and morphological characteristics e.g. slenderness ratio (39-48) and flexibility coefficient (0.37-0.65). The eucalypt species position themselves differently as regards the combination of morphological parameters, therefore allowing species targeting for specific paper properties. By considering these indicators, and the relative species growth, it seems promising to further study E. maculata, E. ovata and E. sideroxylon as potential new paper making eucalypt species, in parallel to the prized E. globulus and the already used E. camaldulensis.