title: Differential anatomical responses to elevated CO2 in saplings of four hardwood species.
abstract: To determine whether an elevated carbon dioxide concentration ([CO(2)]) can induce changes in the wood structure and stem radial growth in forest trees, we investigated the anatomical features of conduit cells and cambial activity in 4-year-old saplings of four deciduous broadleaved tree species - two ring-porous (Quercus mongolica and Kalopanax septemlobus) and two diffuse-porous species (Betula maximowicziana and Acer mono) - grown for three growing seasons in a free-air CO(2) enrichment system. Elevated [CO(2)] had no effects on vessels, growth and physiological traits of Q. mongolica, whereas tree height, photosynthesis and vessel area tended to increase in K. septemlobus. No effects of [CO(2)] on growth, physiological traits and vessels were seen in the two diffuse-porous woods. Elevated [CO(2)] increased larger vessels in all species, except B. maximowicziana and number of cambial cells in two ring-porous species. Our results showed that the vessel anatomy and radial stem growth of Q. mongolica, B. maximowicziana and A. mono were not affected by elevated [CO(2)], although vessel size frequency and cambial activity in Q. mongolica were altered. In contrast, changes in vessel anatomy and cambial activity were induced by elevated [CO(2)] in K. septemlobus. The different responses to elevated [CO(2)] suggest that the sensitivity of forest trees to CO(2) is species dependent.
authors.affiliation: Hokkaido University Forests, FSC, Sapporo, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Takami
authors.initials: T
authors.lastname: Satomura
authors.forename: Kaichiro
authors.initials: K
authors.lastname: Sasa
authors.forename: Ryo
authors.initials: R
authors.lastname: Funada
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Koike
mesh_terms: D031002:Acer / Q000033:anatomy & histology / Q000254:growth & development; D029662:Betula / Q000033:anatomy & histology / Q000254:growth & development; D002245:Carbon Dioxide / Q000502:physiology*; D010788:Photosynthesis; D018547:Plant Stems / Q000033:anatomy & histology / Q000254:growth & development; D029963:Quercus / Q000033:anatomy & histology / Q000254:growth & development; D014197:Trees / Q000033:anatomy & histology / Q000254:growth & development* / Q000502:physiology*; D014867:Water / Q000502:physiology; D014934:Wood / Q000033:anatomy & histology* / Q000254:growth & development
chemical_list: D014867:Water; D002245:Carbon Dioxide