Classification of Principal Wood Species in China Based on the Physiomechanical Properties

Abstract

Many tree species are planted in China with variable properties and usage. Toward exploring the structure-properties relationships of wood and classifying the species more reasonably, the physiomechanical properties of the domestic wood species in China were analyzed statistically. According to the correlation analysis, the mechanical properties were closely related to the wood density. Except impact toughness and cleavage strength, the correlation coefficients between mechanical properties and densities were more than 0.8. However, shrinkage properties showed fewer correlations with densities, and the coefficient was no more than 0.7. Primary component analysis was proved to be feasible to explore the information of the physiomechanical properties. Two principal components (PC1 and PC2) could account for most of the information. PC1 and PC2 were designated as density-dominated and shrinkage-associated factors, respectively. The domestic wood species in China could be classified into 4 clusters based on their physiomechanical properties. According to the cluster results, reasonable grading was proposed for air-dried density, volume shrinkage, modulus of rupture, compression strength parallel to grain and hardness in cross section. The statistical results brought insights into analyzing the physiomechanical properties of domestic Chinese wood species, which was helpful for developing strategies of tree breeding and technologies of wood processing.