Mechanical properties of spruce and beech wood grown in elevated CO2

Abstract

Biomechanical responses of stems of 6-to 7-year-old spruce [Picea abies (L.) Karst.] and beech (Fagus sylvatica L) trees were studied after 4 years of growth in elevated atmospheric CO 2 in combination with a nitrogen treatment and on two different soil types. At the end of the treatment, stems were harvested and tested in fresh and air-dried status. Bending characteristics of juvenile wood (modulus of elasticity, termed rigidity) were determined by bending tests. Fracture characteristics (termed toughness) were determined by stroke-pendulum tests. From the base disk of each stem densitometric data were obtained. In spruce, wood produced under elevated CO 2 was tougher on both soil types; enhanced N deposition made wood less rigid only on acidic soils. In contrast, beech wood samples showed no significant reaction to CO 2 but were significantly tougher under high nitrogen depositions on acidic soil. Effects on wood density of both CO 2 and N treatments were not significant, but wood density was higher on acidic soil and so were rigidity and toughness (soil effect). Different genotypes of spruce and beech reacted significantly differently to the treatments. Some genotypes reacted strongly to CO 2 or N, whereas others did not react or showed interactions between CO 2 and N. This underlines the importance of genetic diversity in tree communities.

Windthrow damage in Picea abies is associated with physical and chemical stem wood properties

“…Spruce grown under N 9 CO 2 -enrichment with two different soil types (an acidic, silty and a calcareous, sandy soil) produced less rigid wood when receiving more nutrients on acidic soil, but not on the naturally more fertile calcareous soil (Beismann et al 2002). The soil type itself influenced elasticity and density of wood, independently of the CO 2 and N-treatment (neither CO 2 nor N-enrichment showed any effect on wood density).…”

Influence of stand density, thinning and elevated CO₂ on stem wood density of spruce

“…Furthermore, elevated atmospheric CO 2 concentration increase wood toughness of spruce seedlings grown on acidic soils by 12 and 18% under low and high levels of nitrogen deposition, respectively. Elevated atmospheric CO 2 also increase the same mechanical wood properties in spruce seedlings grown on calcareous soils by about 17 and 14% under low and high levels of nitrogen deposition (Beismann et al 2002).…”

“…Furthermore, elevated atmospheric CO 2 concentration increase wood toughness of spruce seedlings grown on acidic soils by 12 and 18% under low and high levels of nitrogen deposition, respectively. Elevated atmospheric CO 2 also increase the same mechanical wood properties in spruce seedlings grown on calcareous soils by about 17 and 14% under low and high levels of nitrogen deposition (Beismann et al 2002).The objectives of this study were: (a) to evaluate an influence of elevated atmospheric CO 2 concentration on SWD, (b) to describe the changes of SWD values along the stem vertical profile, (c) to investigate changes of SWD with respect to stand density and thinning. , and in the one tenth of tree height (Ht 1/10 ) ( Table 1).…”

“…Compared to natural growing conditions, a doubling of air's CO 2 concentration would increase wood density of Norway spruce trees about 2-5% (Makinen et al 2002). Kilpelainen et al (2003) For example, at ambient temperatures, approximately 60% increase of the air's CO 2 concentration significantly enhance latewood density (by 27%) and maximum wood density (by 11%), while elevatedtemperature conditions enhance less significantly latewood density (by 25%) and, in contrary, more significantly maximum wood density (by 15%) (Beismann et al 2002). These changes lead to mean overall CO 2 -induced wood density increases of 2.8% at the ambient-temperature and 5.6% at the elevated-temperature (Beismann et al 2002).…”

“…Kilpelainen et al (2003) For example, at ambient temperatures, approximately 60% increase of the air's CO 2 concentration significantly enhance latewood density (by 27%) and maximum wood density (by 11%), while elevatedtemperature conditions enhance less significantly latewood density (by 25%) and, in contrary, more significantly maximum wood density (by 15%) (Beismann et al 2002). These changes lead to mean overall CO 2 -induced wood density increases of 2.8% at the ambient-temperature and 5.6% at the elevated-temperature (Beismann et al 2002). Furthermore, elevated atmospheric CO 2 concentration increase wood toughness of spruce seedlings grown on acidic soils by 12 and 18% under low and high levels of nitrogen deposition, respectively.…”