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

Spatiotemporal dynamics of 20th-century spruce budworm outbreaks in eastern Canada : three distinct patterns of outbreak severity

Berguet Cassy, Martin Maxence, Arseneault Dominique et Morin Hubert. (2021). Spatiotemporal dynamics of 20th-century spruce budworm outbreaks in eastern Canada : three distinct patterns of outbreak severity. Frontiers in Ecology and Evolution, 8, e544088.

[thumbnail of fevo-08-544088.pdf]
Prévisualisation
PDF - Version publiée
Disponible sous licence Creative Commons Attribution (CC-BY 2.5).

2MB

URL officielle: http://dx.doi.org/doi:10.3389/fevo.2020.544088

Résumé

Spruce budworm (SBW) outbreaks are a major disturbance in North American forests. In Quebec, Canada, the recent history of SBW outbreaks at the local scale is well-known. Studies at the Québec scale nonetheless remain rare despite the need to better understand the dynamics of SBW outbreaks at a larger scale. This study aimed to reconstruct the spatiotemporal dynamics of SBW outbreaks during the 20th century across the insect's range in southern Quebec. To this end, we sampled 83 stands throughout southern Quebec. These stands were selected according to their age and the presence of black, white, and red spruce. In fact, spruce, unlike balsam fir, survives the SBW outbreaks and can record them in these growth rings. In each stand, cores were taken from 20 spruce trees. The dendrochronological series of more than 1,600 trees were analyzed, and we identified, through the k-means grouping of stands, the spatial patterns of tree growth for the three previously documented 20th century SBW outbreaks. The outbreaks were not homogeneous across the distribution range of the insect. Two groups of stands showed early- (1905–1930) and late-century (1968–1988) outbreaks of high severity and a mid-century (1935–1965) outbreak of moderate severity. This pattern is explained mainly by the presence of the insect within the balsam fir–yellow birch and balsam fir–white birch bioclimatic domains, areas where outbreaks tend to be most severe because of the abundance of balsam fir, the main SBW host species. However, these two models differ in terms of the duration of outbreaks. A third, more northern, cluster of stands experienced lower severity outbreaks over the 20th century, a pattern explained by a lower proportion of balsam fir trees in these landscapes. Our study shows that, on the one hand, these three groups of stands are defined by outbreaks of specific duration (an outbreak period beginning when more than 20% of the trees are affected and ending when <20% of the trees are affected) and severity (in terms of percentage of affected trees), and on the other hand they are spatially distinct and subject to different climatic conditions.

Type de document:Article publié dans une revue avec comité d'évaluation
ISSN:2296-701X
Volume:8
Pages:e544088
Version évaluée par les pairs:Oui
Date:7 Janvier 2021
Identifiant unique:10.3389/fevo.2020.544088
Sujets: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:insect outbreaks, spatiotemporal dynamics, disturbance severity, dendrochronology, multiscale interactions, climatic conditions, Choristoneura fumiferana (Clem.)
Déposé le:06 juill. 2023 14:35
Dernière modification:06 juill. 2023 14:35
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