Divergent allometric strategies and biomass allocation patterns of four key tree taxa in subtropical China.

Introduction: Accurate forest biomass estimation must simultaneously satisfy the statistical additivity of components and resolve the resource-allocation trade-offs that unfold during tree ontogeny, yet conventional models often fail on both counts and overlook bark as a distinct functional component. Methods: Using destructive-sampling data from 498 trees of Results: Incorporating D²H improved the stem-wood fit, and the additive system explained 93.6-98.4% of the variance in total aboveground biomass. Allometric trajectories revealed divergent strategies. Discussion: Because hardwood bark scales near-isometrically rather than as a constant fraction, ignoring its allometry systematically underestimates carbon stocks in mature broadleaved forests. The resulting taxon- and component-specific equation system provides a directly applicable tool for reducing systematic bias in regional carbon assessment, indicating that carbon accounting should move beyond a purely volumetric perspective toward a component-resolved framework that incorporates life-history allocation strategies.