Open Access Green möglich sobald Postprint bei der ZB eingereicht worden ist.
Within-canopy and ozone fumigation effects on δ¹³C and Δ¹⁸O in adult beech (Fagus sylvatica) trees: Relation to meteorological and gas exchange parameters.
Tree Physiol. 29, 1349-1365 (2009)
In this study, the effects of different light intensities either in direct sunlight or in the shade crown of adult beech (Fagus sylvatica L.) trees on delta C-13 and Delta O-18 were determined under ambient (1 x O-3) and twice-ambient (2 x O-3) atmospheric ozone concentrations during two consecutive years (2003 and 2004). We analysed the isotopic composition in leaf bulk, leaf cellulose, phloem and xylem material and related the results to (a) meteorological data (air temperature, T and relative humidity, RH), (b) leaf gas exchange measurements (stomatal conductance, g(s); transpiration rate, E; and maximum photosynthetic activity, A(max)) and (c) the outcome of a steady-state evaporative enrichment model. delta C-13 was significantly lower in the shade than in the sun crown in all plant materials, whilst Delta O-18 was increased significantly in the shade than in the sun crown in bulk material and cellulose. Elevated ozone had no effect on delta C-13, although Delta O-18 was influenced by ozone to varied degrees during single months. We observed significant seasonal changes for both parameters, especially in 2004, and also significant differences between the study years. Relating the findings to meteorological data and gas exchange parameters, we conclude that the differences in Delta O-18 between the sun and the shade crown were predominantly caused by the Peclet effect. This assumption was supported by the modelled Delta O-18 values for leaf cellulose. It was demonstrated that independent of RH, light-dependent reduction of stomatal conductance (and thus transpiration) and of A(max) can drive the pattern of Delta O-18 increase with the concomitant decrease of delta C-13 in the shade crown. The effect of doubling ozone levels on time-integrated stomatal conductance and transpiration as indicated by the combined analysis of Delta O-18 and delta C-13 was much lower than the influence caused by the light exposure.
Altmetric
Weitere Metriken?
Zusatzinfos bearbeiten
[➜Einloggen]
Publikationstyp
Artikel: Journalartikel
Dokumenttyp
Wissenschaftlicher Artikel
Schlagwörter
evaporative enrichment; light exposure; peclet effect; seasonal and inter-annual differences; carbon-isotope discrimination; air exposure system; spruce picea-abies; organic-matter; leaf water; stomatal conductance; environmental-conditions; physiological
ISSN (print) / ISBN
0829-318X
e-ISSN
1758-4469
Zeitschrift
Tree Physiology
Quellenangaben
Band: 29,
Heft: 11,
Seiten: 1349-1365
Verlag
Oxford University Press
Verlagsort
Oxford
Nichtpatentliteratur
Publikationen
Begutachtungsstatus
Peer reviewed
Institut(e)
Institute of Biochemical Plant Pathology (BIOP)