Titre
Earthquake impacts in old-growth Nothofagus forests in New Zealand
Type
article
Institution
UNIL/CHUV/Unisanté + institutions partenaires
Auteur(s)
Vittoz, P.
Auteure/Auteur
Stewart, G.H.
Auteure/Auteur
Duncan, R.P.
Auteure/Auteur
Liens vers les personnes
Liens vers les unités
ISSN
1100-9233
Statut éditorial
Publié
Date de publication
2001
Volume
12
Numéro
3
Première page
417
Dernière page/numéro d’article
426
Langue
anglais
Résumé
Six stands located on different land forms in mixed old-growth Nothofagus forests in the Matiri Valley (northwest of South Island. New Zealand) were sampled to examine the effects of two recent large earthquakes on tree establishment and tree-ring growth, and how these varied across land forms. 50 trees were cor ed in each stand to determine age structure and the cores were cross-dated to precisely date unusual periods of radial growth. The 1968 earthquake (M = 7.1, epicentre 35 km from the study area) had no discernible impact on the sampled stands. The impact of the 1929 earthquake (M = 7.7, epicentre 20 kin from the study area) varied between stands, depending on whether or not they had been damaged by soil or rock movement. In all stands, the age structures showed a pulse of N. fusca establishment following the 1929 earthquake, with this species dominating establishment in large gaps created by landslides. Smaller gaps, created by branch or tree death, were closed by both N. fusca and N. menziesii. The long period of releases (1929-1945) indicates that direct earthquake damage was not the only cause of tree death, and that many trees died subsequently most likely of pathogen attack or a drought in the early 1930s. The impacts of the 1929 earthquake are compared to a storm in 1905 and a drought in 1974-1978 which also affected forests in the region. Our results confirm that earthquakes are an important factor driving forest dynamics in this tectonically active region, and that the diversity of earthquake impacts is a major source of heterogeneity in forest structure and regeneration.
PID Serval
serval:BIB_696C5D38CC95
Date de création
2008-01-20T14:33:14.263Z
Date de création dans IRIS
2025-05-20T22:23:19Z