Length determination of vessel elements in tree trunks used for water and nutrient transport by Fourier transform Raman spectroscopy

Length analysis of vessel elements in tree trunks used for water and nutrient transport is a lengthy, multistep procedure although it reflects environmental stresses on a tree. The feasibility of using FT-Raman spectroscopy for rapid determination of vessel element length in a tree was examined using wood powders of two Eucalyptus species, including samples of various ages and colors. The first-derivative transformation followed by the multiplicative scatter correction of Raman spectroscopic data and the partial least-squares regression revealed highly significant correlation between conventionally measured and Raman-predicted vessel element length with correlation coefficients (r) of 0.843 and 0.826, respectively, in the calibration (for known samples, n=186) and in the prediction (for unknown samples, n= 40). FT-Raman spectroscopy coupled with multivariate data analysis will contribute to solving the interactions between emerging environmental issues and the anatomical structure of wood, which allow efficient management practices in growing forests to fix atmospheric CO₂ effectively.