Analyse des communautés lichéniques de deux parcelles différemment dépérissantes d'une érablière des environs de Québec, Canada
[Analysis of the lichen communities of two differently die back-affected plots in a maple forest stand near Québec city, Canada]
Bastien, D.; Villeneuve, N.; Grandtner, M. M.; Gervais, C.
The lichen communities of two differently dieback-affected plots in a maple forest stand at Duchesnay, near Québec city (Canada), were identified and compared together. Cluster analysis of the 44 species found on 17 maple trees (Acer saccharum Marsh.) revealed the presence of two types of lichen communities composed of six different groups. Ordination in reduced space of both communities showed a significant correlation between the dieback rate of trees and the species composition of their lichen communities. Moreover, the lichen diversity was more important in the most dieback-affected plot where some heliophilous and many acidophilous species, usually absent on healthy maple trees, were present. The canopy breakdown, associated with the dieback, could be responsible for the establishment of these species following the increase of light and the loss of the foliage buffer action.