Claim · model-written summary
Elevated O3 caused disturbances in stomatal conductance of open-soil-grown birch trees.
- Taxon
- Betula pendula
Betula pendulae1 - Treatment
- 1.6x ambient (elevated) O3 concentratione3
- Outcome
- stomatal conductancee4
- Comparator
- ambient (control)e3
- Setting
- free air O3 exposure facilitye3
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleDirectionValueQualifier
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Physiological responses of 4-year-old potted saplings of an O3-tolerant clone of Betula pendula Roth to short-term ozone (O3) exposure (one growing season) were compared with those of 6-year-old open-soil-grown trees of the same clone fumigated with O3 for six growing seasons”
e3“both groups of plants were exposed to ambient (control) and 1.6x ambient (elevated) O3 concentration under similar microclimatic conditions in a free air O3 exposure facility”
e4“disturbances in stomatal conductance”
Title
E. Oksanen Tree Physiology 2003. doi:10.1093/treephys/23.9.603
Other claims from this paper (11)
- Intervention effect Potted saplings were unaffected by elevated O3 concentration.
- Intervention effect Open-soil-grown birch trees showed a 3-38% reduction in shoot growth under elevated O3.
- Intervention effect Open-soil-grown birch trees had 22% fewer overwintering buds under elevated O3.
- Intervention effect Open-soil-grown birch trees had a 26-65% decrease in autumnal net photosynthesis under elevated O3.
- Intervention effect Senescing leaves of open-soil-grown birch trees had 30% lower starch concentration under elevated O3.
- Intervention effect Senescing leaves of open-soil-grown birch trees had 20-23% lower nitrogen concentration under elevated O3.
- Mechanism The greater O3 sensitivity of open-soil-grown birch trees was a result of senescence-related physiological factors.
- Mechanism A lower net photosynthesis to stomatal conductance ratio in open-soil-grown trees promoted O3 uptake and led to visible foliar injuries.
- Mechanism Decreased carbohydrate reserves may have caused deleterious carry-over effects through reduced over-wintering bud formation.
- Mechanism Leaf-level O3 load was higher in open-soil-grown trees than in potted saplings because of slower leaf senescence in the trees.
- Association O3 sensitivity in European white birch increases with longer exposure time and larger tree size.