Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Stem cycle analyses help decipher the nonlinear response of trees to concurrent warming and drought

Balducci Lorena, Deslauriers Annie, Rossi Sergio et Giovannelli Alessio. (2019). Stem cycle analyses help decipher the nonlinear response of trees to concurrent warming and drought. Annals of Forest Science, 76, e88.

[thumbnail of s13595-019-0870-7.pdf]
PDF - Version publiée
Disponible sous licence Creative Commons (CC-BY 2.5).


URL officielle:


Key message High-resolution analysis of stem radius variation can quantify the impact of warming and drought on stem water balance and stem growth in black spruce [ Picea mariana (Mill.) B.S.P.)]. Drought affected plant water status and stem growth. However, warming affects the components of the circadian stem cycle differently if the impacts occur in the daytime or nighttime. The interactive effect of abiotic stresses had less impact on the circadian stem cycle than when the stresses occurred independently.

Context Warming and recent droughts in boreal regions reflect the multiple dimensions of climate change. How these climate-related stresses will affect the stem growth of trees remains to be described. Plant water relations can detect the dynamics of stem depletion and replenishment under conditions of climate-forced stress.

Aims This study aimed to verify the impacts of a combination of asynchronous warming (nighttime versus daytime warming) and drought on stem water balance and stem growth in black spruce [Picea mariana (Mill.) B.S.P.)].

Methods We investigated the water status and variations in stem radius of black spruce saplings growing in a controlled environment from May through August. We grew four-year-old saplings in warmer conditions either during the day (DW) or night (NW) at temperatures ca. 6 °C warmer than the ambient air temperature (CT). We then simulated a one-month drought in June. Automatic point dendrometers provided a high-resolution analysis of variations in stem radius, and we also monitored leaf water potentials and volumetric soil water content during the entire experimental period.

Results We detected significant reductions in stem radius variation under water deficit conditions. In the daytime warming scenario, we observed a significant increase in the duration of contraction and a decrease in expansion of the stems. The amplitude of this contraction and expansion was reduced under the nighttime warming conditions. The main effect of warming was to enhance drought stress by accelerating soil water depletion. Changes in predawn water potential drove the duration of stem circadian cycles under conditions of daytime warming, whereas irreversible growth dynamics drove these cycles under nighttime warming conditions due to the midday water potential. The interaction of night/daytime asynchronous warming and drought reduced the amplitude rather than the duration of stem contraction and expansion.

Conclusion Water deficit decreased stem growth during the growing season. Asymmetric warming (as a single independent treatment) affected the timing and magnitude of stem circadian cycles. Under daytime warming scenarios, the duration of contraction and expansion were regulated mainly by predawn water potential, inducing longer (shorter) durations of contraction (expansion). Under nighttime warming, the smaller amplitudes of stem contraction and expansion were associated with midday water potential. Therefore, the interaction of abiotic stresses had less of an impact on the circadian stem cycle components than when these stresses were applied independently.

Type de document:Article publié dans une revue avec comité d'évaluation
Version évaluée par les pairs:Oui
Date:22 Août 2019
Identifiant unique:10.1007/s13595-019-0870-7
Sujets:Sciences naturelles et génie > Sciences appliquées > Climatologie et météorologie
Sciences naturelles et génie > Sciences appliquées > Foresterie et sciences du bois
Sciences naturelles et génie > Sciences naturelles > Biologie et autres sciences connexes
Département, module, service et unité de recherche:Unités de recherche > Centre de recherche sur la Boréalie (CREB)
Départements et modules > Département des sciences fondamentales
Mots-clés:asynchronous warming, water deficit, point dendrometer, water status, aplings, black spruce
Déposé le:24 mai 2023 15:17
Dernière modification:24 mai 2023 15:17
Afficher les statistiques de telechargements

Éditer le document (administrateurs uniquement)

Creative Commons LicenseSauf indication contraire, les documents archivés dans Constellation sont rendus disponibles selon les termes de la licence Creative Commons "Paternité, pas d'utilisation commerciale, pas de modification" 2.5 Canada.

Bibliothèque Paul-Émile-Boulet, UQAC
555, boulevard de l'Université
Chicoutimi (Québec)  CANADA G7H 2B1
418 545-5011, poste 5630