Lionel Humbert

PhD student
Using tree rings to detect and understand inter-annual variations in the carbon balance of the boreal biome.
Université du Québec à Montréal
Director: Berninger Frank
Codirector: St-Onge Benoît

Personal website 

  • M.Sc. Biology, 2006 (Université du Québec à Montréal, Canada)
  • Predoctoral research in forest ecology, 2003 (Université Henry Poincaré, Nancy I, France)
  • Master's Degree in Population and Ecosystem Biology, 2002 (Université Henry Poincaré, Nancy I, France)

The aim of my dissertation research is to determine whether variation in boreal net primary productivity, as estimated from tree rings, is related to carbon exchange in the boreal biome. Specifically, we will test:

  • If high frequency variation (year-to-year) in growth is correlated with the size of the boreal carbon sink.
  • If growth data from the circumpolar tree line and other suitable sites in the boreal zone confirm whether a general growth increase exists and if the size of the increase in NPP accords with the size of a boreal carbon sink.
  • If the growth increase is in line with the presumed effects of increasing CO2, increasing growing season length or increasing nutrient availability.

I have developed some projects with several faculty during my Master’s at UQAM, regarding various aspects of plant ecology:

I also have been doing simulations with a new statistical approach based on blind source separation by Independent Component Analysis (ICA) to test its robustness with ecological data:

  • Bat species and individual recognition with high-energy sound wave records with François Fabianek and Daniel Gagnon.
  • Dambrine E., Dupouey J.-L., Laüt L., Humbert L., Thinon M., Beaufils T. and Richard H., 2007. Present forest biodiversity patterns in France related to former roman agriculture. Ecology 88(6): 1430-1439. Paper 
  • Humbert L., Gagnon D., Kneeshaw D., Messier C., 2007. A shade tolerance index for common understory species of northeastern North America. Ecological Indicators 7: 195-207. Paper , Abstract/Bibtex 
  • Tolerance and niche breadth of understory plant species for pH and light. M.Sc. Thesis, 2006. (in French)
  • Forest evolution since Gallo-Roman period in the oak forest of Tronçais (Allier, France): Pedo-anthracological approach. Predoctoral research report, 2003. (in French)
  • Humbert L., Berninger F., 2007. Recovering climatic components and aerosol effects in Nepalese and Russian tree ring width. ESA/SER joint meeting 07/08/07. San José, California, USA. Abstract 
  • Humbert L., Berninger F., 2006. Extracting growth and environmental patterns from tree ring series with independent component analysis. 7th International Conference on Dendrochronology 13/06/06. Beijing, China. ICD web site 
  • Humbert L., Gagnon D., Kneeshaw D., Messier C., 2005. Light suitability index for the most common understory plant species in Quebec. 5th North American Forest Ecology Workshop 13/06/05. Aylmer, Quebec.
  • Work T., Humbert L., 2005. Community Ecology with R. GREFi-CRBF workshop "Semin-R". 18/04/05. Montreal, Quebec.
  • Dambrine E., Dupouey J.L., Laüt L., Humbert L., , Thinon M., 2004. Pedologists, botanists, and archaeologists; a fertile ethnic relation to understand distribution of soils in the forest of Tronçais (France). 8th Journées Nationales d'Etude des Sols. 26/10/04. Bordeaux, France.
  • Dambrine E. et Dupouey J.L., Humbert L., Laffite J.D., Laüt L., Leroy M., Thinon M., 2004. The memory of forest ecosystems. Impact of former land use on soil properties and biodiversity in present forests. EUROSOIL 2004. 06/09/04. Freiburg, Germany.
  • Humbert L., Berninger F., 2007. Blind source separation of climatic components from Nepalese tree ring widths. 1st symposium of The Centre for Forest Research 29/03/07. Montreal, QC, Canada. Abstract 
  • Humbert L., Messier C., Kneeshaw D., Berninger F., 2007. Key characteristics of European plants invasiveness in North America. 1st symposium of The Centre for Forest Research 29/03/07. Montreal, QC, Canada. Abstract 
  • Statistics with R
  • Japanese (notions)
  • Photos (Some photos taken in the Abitibi and James Bay regions)

Duparquet lake, Abitibi (Summer 2006)

Waswanipi river, James Bay (Summer 2006)

See all CFR pictures... 

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