title: Stem respiration of Populus species in the third year of free-air CO2 enrichment.
abstract: Carbon cycling in ecosystems, and especially in forests, is intensively studied to predict the effects of global climate change, and the role which forests may play in 'changing climate change'. One of the questions is whether the carbon balance of forests will be affected by increasing atmospheric CO2 concentrations. Regarding this question, effects of elevated [CO2] on woody-tissue respiration have frequently been neglected. Stem respiration of three Populus species (P. alba L. (Clone 2AS-11), P. nigra L. (Clone Jean Pourtet), and P. x euramericana (Clone I-214)) was measured in a managed, high-density forest plantation exposed to free-air CO2 enrichment (POPFACE). During the period of measurements, in May of the third year, stem respiration rates were not affected by the FACE treatment. Moreover, FACE did not influence the relationships between respiration rate and both stem temperature and relative growth rate. The results were supported by the reported absence of a FACE-effect on growth and stem wood density.
authors.affiliation: University of Antwerp, Department of Biology, Research Group of Plant and Vegetation Ecology, Universiteitsplein 1, B-2610 Wilrijk, Belgium Università degli Studi della Tuscia, Department of Forest Environment and Resources (DISAFRI), Via S. Camillo de Lellis, I-01100 Viterbo, Italy.
authors.forename: Birgit
authors.initials: B
authors.lastname: Gielen
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Scarascia-Mugnozza
authors.forename: Reinhart
authors.initials: R
authors.lastname: Ceulemans