Xylem Pit Anatomy and Minimum Leaf Conductance Drive Drought Mortality in Pinus pinaster.

ABSTRACT: Drought-triggered forest die-off events are commonly attributed to hydraulic failure, carbon starvation, or a combination of the two. Nevertheless, the anatomical and physiological traits that make trees vulnerable to drought in the field are often unknown, hindering predictive efforts. To identify these traits, we compared coexisting declining (D, heavily defoliated) and non-declining (ND, lightly defoliated) trees. We studied a recent die-off event affecting maritime pine (Pinus pinaster) in north-eastern Spain that started after the severe 2017 drought. We compared the depth of soil water uptake, estimated using δ¹⁸O and δ²H in soil and xylem water samples, as well as field measurements. We also measured anatomical and physiological wood and leaf variables, paying

SUBMITTER: Camarero JJ 

PROVIDER: S-EPMC12675989 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature