Tree-ring Laboratory

A dendroecological approach is based on the principle that trees record past ecological events. Reconstruction techniques vary and include the analysis of the age structure of tree and shrub populations, of growth forms, of annual wood growth and morphological anomalies, in addition to anatomy and physical properties of annual rings. The originality of the laboratory work is expressed by the multidisciplinary study topics, which range from reconstruction of paleoclimates, tree line dynamics, analysis of geomorphological processes (landslides, river flooding, dune movements), to analysis of plant-herbivore relationships (migration of caribou populations and defoliating insect outbreaks).

The laboratory includes workshops for preparing wood samples for analysis (cutting and sanding). Several types of analyses can be conducted using the equipment in the lab:

  • Recognition of diagnostic rings and measurement of ring widths (binocular microscopes and micrometers)
  • Measurement of wood density (Dendrocut two-bladed saw, Soxhlet extractor, Balteau x-ray machine in an air-conditioned darkroom, and Walesch Electronics Dendro 2003 densitometer)
  • Measurement of anatomic structures (microtome and microscope fitted with an image analysis system)
  • Wood and charcoal identification (optical microscope and scanning electron microscope)

The laboratory has constructed several reference series (ring width and wood density) for different regions of Quebec (one series in the St. Lawrence Valley provides dates for archaeological wood from different periods in history) as well as a chronology of diagnostic rings (pale and frost rings) in subarctic Quebec. These series allow the reconstruction past events by dating dead trees. Events include fires, insect outbreaks, glacial activity, water level fluctuations, landslides, permafrost degradation, etc.


 

Contact : Ann Delwaide

 

Room 3131
Abitibi-Price Building
Université Laval
2405 rue de la Terrasse
Québec, Canada
G1V 0A6

Phone : (418) 656-2131 ext. 6937