© 2005 Heron Publishing—Victoria, Canada
Scots pine responses to elevated temperature and carbon dioxide concentration: growth and wood properties
Antti Kilpeläinen (1, 2), Heli Peltola (1), Aija Ryyppö (1) and Seppo Kellomäki (1)
1. University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland / 2. Corresponding author (antti.kilpelainen@joensuu.fi) / Received January 19, 2004; accepted June 20, 2004; published online November 1, 2004
Summary
Growth and wood properties of 20-year-old Scots pine (Pinus sylvestris L.) trees were studied for 6 years in 16 closed chambers providing a factorial combination of two temperature regimes (ambient
and elevated) and two carbon dioxide concentrations ([CO2]) (ambient and twice ambient). The elevation of temperature corresponded to the predicted effect at the site of a doubling
in atmospheric [CO2]. Annual height and radial growth and wood properties were analyzed during 1997–2002. Physical wood properties analyzed included
early- and latewood widths and their proportions, intra-ring wood densities, early- and latewood density and mean fiber length.
Chemical wood properties analyzed included concentrations of acetone-soluble extractives, lignin, cellulose and hemicellulose.
There were no significant treatment effects on height growth during the 6-year study. Elevated [CO2] increased ring width by 66 and 47% at ambient and elevated temperatures, respectively. At ambient [CO2], elevated temperature increased ring width by 19%. Increased ring width in response to elevated [CO2] resulted from increases in both early- and latewood width; however, there was no effect of the treatments on early- and
latewood proportions. Mean wood density, earlywood density and fiber length increased in response to elevated temperature.
The chemical composition of wood was affected by elevated [CO2], which reduced the cellulose concentration, and by elevated temperature, which reduced the concentration of acetone-soluble
extractives. Thus, over the 6-year period, radial growth was significantly increased by elevated [CO2], and some wood properties were significantly affected by elevated temperature or elevated [CO2], or both, indicating that climate change may affect the material properties of wood.
Keywords:
chemical composition of wood, climate change, earlywood, fiber length, height growth, latewood, radial growth, ring width,
wood density.
