Die hard: timberline conifers survive annual winter embolism - INRA - Institut national de la recherche agronomique Accéder directement au contenu
Article Dans Une Revue New Phytologist Année : 2019

Die hard: timberline conifers survive annual winter embolism

Résumé

During winter, timberline trees are exposed to drought and frost, factors known to induce embolism. Studies indicated that conifers cope with winter embolism by xylem refilling. We analysed the loss of hydraulic conductivity (LC) in Picea abies branch xylem over 10 years, and correlated winter embolism to climate parameters. LC was investigated by direct X-ray micro-computer tomography (micro-CT) observations and potential cavitation fatigue by Cavitron measurements. Trees showed up to 100% winter embolism, whereby LC was highest, when climate variables indicated frost drought and likely freeze-thaw stress further increased LC. During summer, LC never exceeded 16%, due to hydraulic recovery. Micro-CT revealed homogenous embolism during winter and that recovery was based on xylem refilling. Summer samples exhibited lower LC in outermost compared to older tree rings, although no cavitation fatigue was detected. Long-term data and micro-CT observations demonstrate that timberline trees can survive annual cycles of pronounced winter-embolism followed by xylem refilling. Only a small portion of the xylem conductivity cannot be restored during the first year, while remaining conduits are refilled without fatigue during consecutive years. We identify important research topics to better understand the complex induction and repair of embolism at the timberline and its relevance to general plant hydraulics.
Fichier principal
Vignette du fichier
2019_Mayr_New_Phytol.pdf (928.27 Ko) Télécharger le fichier
Origine : Accord explicite pour ce dépôt
Loading...

Dates et versions

hal-02394658 , version 1 (04-12-2019)

Licence

Paternité

Identifiants

Citer

Eric Badel, Barbara Beikircher, Feng Feng, Stefan Mayr. Die hard: timberline conifers survive annual winter embolism. New Phytologist, 2019, 8 p. ⟨10.1111/nph.16304⟩. ⟨hal-02394658⟩
48 Consultations
101 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More