Hydraulic plasticity and water use regulation act to maintain the hydraulic safety margins of Mediterranean trees in rainfall exclusion experiments
BADEL, Eric
Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant [PIAF]
Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant [PIAF]
COCHARD, Hervé
Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant [PIAF]
Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant [PIAF]
ORMEÑO, Elena
Centre National de la Recherche Scientifique [CNRS]
Institut méditerranéen de biodiversité et d'écologie marine et continentale [IMBE]
Centre National de la Recherche Scientifique [CNRS]
Institut méditerranéen de biodiversité et d'écologie marine et continentale [IMBE]
FERNANDEZ, Catherine
Institut méditerranéen de biodiversité et d'écologie marine et continentale [IMBE]
< Réduire
Institut méditerranéen de biodiversité et d'écologie marine et continentale [IMBE]
Langue
en
Article de revue
Ce document a été publié dans
Plant, Cell and Environment. 2024-07-30, vol. 47, n° 12, p. 4741-4753
Wiley
Résumé en anglais
Hydraulic failure due to xylem embolism has been identified as one of the main mechanisms involved in drought‐induced forest decline. Trees vulnerability to hydraulic failure depends on their hydraulic safety margin (HSM). ...Lire la suite >
Hydraulic failure due to xylem embolism has been identified as one of the main mechanisms involved in drought‐induced forest decline. Trees vulnerability to hydraulic failure depends on their hydraulic safety margin (HSM). While it has been shown that HSM globally converges between tree species and biomes, there is still limited knowledge regarding how HSM can adjust locally to varying drought conditions within species. In this study, we relied on three long‐term partial rainfall exclusion experiments to investigate the plasticity of hydraulic traits and HSM for three Mediterranean tree species ( Quercus ilex L., Quercus pubescens Willd ., and Pinus halepensis Mill .). For all species, a homeostasis of HSM in response to rainfall reduction was found, achieved through different mechanisms. For Q. ilex , the convergence in HSM is attributed to the adjustment of both the turgor loss point (Ψtlp) and the water potential at which 50% of xylem conductivity is lost due to embolism (P50). In contrast, the maintenance of HSM for P. halepensis and Q. pubescens is related to its isohydric behavior for the first and leaf area adjustment for the latter. It remains to be seen whether this HSM homeostasis can be generalized and if it will be sufficient to withstand extreme droughts expected in the Mediterranean region.< Réduire
Mots clés en anglais
cuticular conductance
evergreen and deciduous trees
hydraulic adjustment
hydraulic failure
phenotypic plasticity
stomatal control
throughfall exclusion
turgo
Origine
Importé de halUnités de recherche