title: Updated stomatal flux and flux-effect models for wheat for quantifying effects of ozone on grain yield, grain mass and protein yield.
abstract: Field measurements and open-top chamber experiments using nine current European winter wheat cultivars provided a data set that was used to revise and improve the parameterisation of a stomatal conductance model for wheat, including a revised value for maximum stomatal conductance and new functions for phenology and soil moisture. For the calculation of stomatal conductance for ozone a diffusivity ratio between O(3) and H(2)O in air of 0.663 was applied, based on a critical review of the literature. By applying the improved parameterisation for stomatal conductance, new flux-effect relationships for grain yield, grain mass and protein yield were developed for use in ozone risk assessments including effects on food security. An example of application of the flux model at the local scale in Germany shows that negative effects of ozone on wheat grain yield were likely each year and on protein yield in most years since the mid 1980s.
authors.affiliation: Department of Plant Ecology, Justus-Liebig University, Heinrich-Buff-Ring 26, D-35392 Giessen, Germany. Ludger.Gruenhage@bot2.bio.uni-giessen.de
authors.forename: Ludger
authors.initials: L
authors.lastname: Grünhage
authors.forename: Håkan
authors.initials: H
authors.lastname: Pleijel
authors.forename: Gina
authors.initials: G
authors.lastname: Mills
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bender
authors.forename: Helena
authors.initials: H
authors.lastname: Danielsson
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Lehmann
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Castell
authors.forename: Olivier
authors.initials: O
authors.lastname: Bethenod
mesh_terms: D000383:Agriculture; D000393:Air Pollutants / Q000633:toxicity*; D004784:Environmental Monitoring; D008954:Models, Biological; D010126:Ozone / Q000633:toxicity*; D010940:Plant Proteins / Q000378:metabolism; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological; D014908:Triticum / Q000187:drug effects / Q000502:physiology*
chemical_list: D000393:Air Pollutants; D010940:Plant Proteins; D010126:Ozone