title: How closely does stem growth of adult beech (Fagus sylvatica) relate to net carbon gain under experimentally enhanced ozone stress?
abstract: The hypothesis was tested that O(3)-induced changes in leaf-level photosynthetic parameters have the capacity of limiting the seasonal photosynthetic carbon gain of adult beech trees. To this end, canopy-level photosynthetic carbon gain and respiratory carbon loss were assessed in European beech (Fagus sylvatica) by using a physiologically based model, integrating environmental and photosynthetic parameters. The latter were derived from leaves at various canopy positions under the ambient O(3) regime, as prevailing at the forest site (control), or under an experimental twice-ambient O(3) regime (elevated O(3)), as released through a free-air canopy O(3) fumigation system. Gross carbon gain at the canopy-level declined by 1.7%, while respiratory carbon loss increased by 4.6% under elevated O(3). As this outcome only partly accounts for the decline in stem growth, O(3)-induced changes in allocation are referred to and discussed as crucial in quantitatively linking carbon gain with stem growth.
authors.affiliation: Department of Plant Ecology, Forestry and Forest Products Research Institute, Tsukuba 305-8687, Japan. kitao@ffpri.affrc.go.jp
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Kitao
authors.forename: J Barbro
authors.initials: JB
authors.lastname: Winkler
authors.forename: Markus
authors.initials: M
authors.lastname: Löw
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Nunn
authors.forename: Daniel
authors.initials: D
authors.lastname: Kuptz
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Häberle
authors.forename: Ilja M
authors.initials: IM
authors.lastname: Reiter
authors.forename: Rainer
authors.initials: R
authors.lastname: Matyssek
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D002244:Carbon / Q000378:metabolism*; D029964:Fagus / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology; D008954:Models, Biological; D010126:Ozone / Q000633:toxicity*; D010788:Photosynthesis / Q000187:drug effects; D018547:Plant Stems / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology; D013312:Stress, Physiological
chemical_list: D000393:Air Pollutants; D010126:Ozone; D002244:Carbon