Effect of Elevated Carbon Dioxide Concentration on Carbon Assimilation under Fluctuating Light

0384364 - ÚVGZ 2013 RIV US eng J - Journal Article
Holišová, Petra - Zitová, Martina - Klem, Karel - Urban, Otmar
Effect of Elevated Carbon Dioxide Concentration on Carbon Assimilation under Fluctuating Light.
Journal of Environmental Quality. Roč. 41, č. 6 (2012), s. 1931-1938. ISSN 0047-2425. E-ISSN 1537-2537
R&D Projects: GA MŠMT(CZ) ED1.1.00/02.0073; GA ČR(CZ) GAP501/10/0340; GA MŠMT(CZ) LM2010007; GA AV ČR IAA600870701
Institutional support: RVO:67179843
Keywords : carbon * light * beech * spruce * carbon assimilation * elevate carbon * dioxide concentration * mol * photosynthetic * assimilation * carbon dioxide * dioxide * concentracion * leave * photosynthetic efficiency
Subject RIV: EH - Ecology, Behaviour
Impact factor: 2.353, year: 2012

Natural fluctuations in light intensity may significantly affect the amount of CO assimilated by plants and ecosystems. Little is known, however, about the interactive effect of dynamic light conditions and atmospheric CO concentrations. The hypothesis that elevated CO concentration (EC; 700 μmol CO mol) increases photosynthetic efficiency in dynamic light environments as compared to ambient CO concentration (AC; 385 μmol CO mol) was tested. Sun leaves of European beech ( L.) and current-year shoots of Norway spruce [ (L). Karst.] were exposed to five dynamic light regimes (LRs) occurring within forest canopies due to variable cloud cover or self-shading of leaves and to a steady-state LR. The LRs differed in the time course of incident irradiance, whereas the overall duration (600 s) and total amount of radiation (35.88 mmol photons m) were the same in all LRs. The EC treatment enhanced the amount of CO assimilated under all LRs tested. While the stimulation was only 37 to 50% in beech, it was 52 to 85% in spruce. The hypothesis that photosynthetic efficiency is stimulated by EC was confirmed in LRs when the leaves were pre-exposed to low light intensity and photosynthetic induction was required. By contrast, only a minor effect of EC treatment was found on the rate of induction loss and postillumination CO fixation in both species studied.
Permanent Link: http://hdl.handle.net/11104/0214046