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

The effects of throughfall exclusion on xylogenesis of balsam fir

D'Orangeville Loïc, Cote Benoît, Houle Daniel et Morin Hubert. (2013). The effects of throughfall exclusion on xylogenesis of balsam fir. Tree Physiology, 33, (5), p. 516-526.

Le texte intégral n'est pas disponible pour ce document.

URL officielle: http://dx.doi.org/doi:10.1093/treephys%2Ftpt027

Résumé

A 20-40% reduction in soil moisture is projected for the boreal forest of Eastern Canada for the period 2070-99 relative to 1971-2000. In order to better predict the effects of a reduced water supply on the growth of balsam fir (Abies balsamea (L.) Mill.), a dominant tree species of the boreal forest, we simulated 2 consecutive years of summer droughts (starting in July) by means of throughfall exclusion. Four 100-m2 plots were established in 2010 with polyethylene sheets maintained 1.3-2 m aboveground and redirecting the water outside the plots. Wood microcores were extracted weekly from mature trees from April to October 2011 to analyse the time dynamics of wood formation in that year. The number of tracheids formed during and before treatment and their anatomical characteristics were determined through microscopic analyses. The growth of lateral and terminal branches and the water potential of balsam fir seedlings were also monitored. Throughfall exclusion significantly reduced soil water content by 5.8% in 2010 and 10.5% in 2011. Xylogenesis was affected significantly by the treatment. Tracheids were 16.1% smaller in diameter and their cell wall was 14.1% thicker during both years. The treatment delayed by more than a week the start of the tracheid differentiation process in the second year with a concomitant decrease (26%) in the number of tracheids produced. The seedlings displayed a 32% reduction in growth and a 40% reduction in leaf water potential. Our results suggest that a future regime of increased frequency and intensity of droughts could have negative effects on the duration of xylogenesis and the production of xylem cells in balsam fir.

Type de document:Article publié dans une revue avec comité d'évaluation
ISSN:0829-318X
Volume:33
Numéro:5
Pages:p. 516-526
Version évaluée par les pairs:Oui
Date:2013
Identifiant unique:10.1093/treephys/tpt027
Sujets:Sciences naturelles et génie > Sciences naturelles > Biologie et autres sciences connexes
Département, module, service et unité de recherche:Départements et modules > Département des sciences fondamentales
Unités de recherche > Centre de recherche sur la Boréalie (CREB)
Mots-clés:Abies balsamea, climate change, drought, radial/secondary growth, tracheid, water stress
Déposé le:06 juin 2023 14:13
Dernière modification:06 juin 2023 14:15
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