The influence of elevated CO2 on growth parameters of various provenances of European beech (Fagus sylvatica L.) at different irradiance.

摘要

In a greenhouse experiment one-year-old seedlings of seven provenances of beech (Fagus sylvatica) were grown under controlled conditions at two CO2 concentrations (350 ppm and 650 ppm) and different light intensities (2%, 17% and 100% relative irradiance). The response of the plants to the various treatments was investigated by means of the leaf development during the growing season. At the end of the vegetation period leaf area and leaf dry weight per single leaf and per plant were measured. At the beginning of the growing period the provenances differed significantly in height and at the end of the vegetation period also in the mean leaf number, leaf area and leaf dry weight per plant. The area per single leaf was - in contrast to leaf dry weight and the specific leaf area - similar among all seven provenances. Light had an effect on all measured leaf parameters. In full light leaf development started very early. Leaf number, leaf area, and leaf dry weight per single leaf and per plant decreased and specific leaf area increased under low light conditions. In the treatment 'increased CO2 environment and full irradiance' leaf number, leaf area and leaf dry weight per single leaf and per plant also increased. At reduced irradiance a higher CO2 concentration did not influence the measured leaf parameters..