Characterization of Silver fir Wood Decay Classes Using Sugar Metabolites Detected with Ion Chromatography

Hunter’s classification is the most adopted method for describing coarse woody debris (CWD) decay stages; however, wood chemical characterization is often lacking. This study explores the sugar profiles of living silver fir (Abies alba Mill.) trees and CWD samples in Hunter’s five-decay stages, evaluating the trends and variability in sugar content in CWD samples during decomposition. Wood cores from living trees and CWD samples from two different forest sites in Trentino (Italy) were analyzed after extraction using ion-exchange chromatography, equipped with pulsed amperometric and charge aerosol detectors (IC-PAD-CAD). Detailed monosaccharides, disaccharides, and sugar alcohol profiles of living wood and CWD samples were described. Cellobiose, arabinose, maltose, and trehalose showed similar trend in both the sites. Principal component analysis (PCA) highlighted the good capability of sugar profiles to well characterize and discriminate silver fir wood samples among Hunter’s categories of wood decomposition.