Decoupling of Tree-Ring Cellulose δ¹⁸O and δ²H Highlighted by Their Contrasting Relationships to Climate and Tree Intrinsic Variables.

ABSTRACT: Oxygen (δ¹⁸O) and hydrogen (δ²H) stable isotope ratios are tightly coupled in precipitation and, albeit damped, in leaf water, but are often decoupled in tree-ring cellulose. The environmental and physiological conditions in which this decoupling occurs are not yet well understood. We investigated the relationships between δ¹⁸O and δ²H and tree-ring width (TRW), tree crown volume, tree age and climate in silver fir and Douglas-fir and found substantial differences between δ¹⁸O and δ²H. Overall, δ¹⁸O-δ²H correlations were weak to absent but became significantly negative under high summer vapour pressure deficit (VPD). δ¹⁸O and δ²H had positive and negative nonlinear relationships wi

SUBMITTER: Charlet de Sauvage J 

PROVIDER: S-EPMC11788974 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature