title: Scots pine responses to elevated temperature and carbon dioxide concentration: growth and wood properties.
abstract: 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.
authors.affiliation: University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland. antti.kilpelainen@joensuu.fi
authors.forename: Antti
authors.initials: A
authors.lastname: Kilpeläinen
authors.forename: Heli
authors.initials: H
authors.lastname: Peltola
authors.forename: Aija
authors.initials: A
authors.lastname: Ryyppö
authors.forename: Seppo
authors.initials: S
authors.lastname: Kellomäki
mesh_terms: D002245:Carbon Dioxide; D008031:Lignin / Q000032:analysis; D041605:Pinus sylvestris / Q000254:growth & development* / Q000502:physiology; D018547:Plant Stems / Q000254:growth & development; D013696:Temperature; D014197:Trees / Q000254:growth & development* / Q000502:physiology; D014934:Wood / Q000737:chemistry / Q000254:growth & development
chemical_list: D002245:Carbon Dioxide; D008031:Lignin