New critical levels for ozone effects on young trees based on AOT40 and simulated cumulative leaf uptake of ozone

Responses of evergreen and deciduous Quercus species to enhanced ozone levels

“…For deciduous oaks, the parameterization by Karlsson et al (2004) was used, while for the evergreen oak, Q. ilex, a parameterization for this species included in the 2009 revision of the Mapping Manual (2004) was applied (Table 2). Meteorological data (from a meteorological tower placed at the experimental site) and hourly ozone concentrations covered from 1st April to 30th September.…”

“…As for European oaks, Q. petraea (Broadmeadow et al, 1999;Broadmeadow and Jackson, 2000;Karlsson et al, 2004), Q. robur (e.g. Broadmeadow et al, 1999;Broadmeadow and Jackson, 2000;Karlsson et al, 2004), Q. ilex (Inclán et al, 1999;Manes et al, 1998;Ribas et al, 2005aRibas et al, , 2005b and Q. coccifera have been exposed previously to enhanced ozone levels. Such studies focussed on one or two oak species, sometimes comparing them with species of other genera.…”

“…More recently, a range of flux-based CLe have been proposed for different types of vegetation: the Phytotoxic Ozone Dose above the threshold of Y nmol m À2 s À1 (POD Y ) (Harmens et al, 2010), previously known as accumulated stomatal flux of ozone above the threshold of Y, AF st Y (UNECE, 2004). In the dose-response functions between growth and AOT40 or POD Y from which such CLe were derived e including a CLe for deciduous Quercus species (Karlsson et al, 2004) e, the threshold for POD Y was Y ¼ 1.6 and a 5% growth reduction was regarded as relevant. However, in a very recent approach (Harmens et al, 2010), lower thresholds (Y ¼ 0 and Y ¼ 1) and percentages of biomass reductions (2% or 4%) have been proposed for Norway spruce, birch and beech, although not for Quercus.…”

“…However, in a very recent approach (Harmens et al, 2010), lower thresholds (Y ¼ 0 and Y ¼ 1) and percentages of biomass reductions (2% or 4%) have been proposed for Norway spruce, birch and beech, although not for Quercus. In the present paper, in order to facilitate comparability with previous studies (e.g., Karlsson et al, 2004), the discussion will be mainly based in POD 1.6 and a 5% growth reduction will be considered. However, accumulated ozone stomatal fluxes will also be reported for Y ¼ 1 and ¼ 0.…”

Implementation of a module for risk of ozone impacts assessment to vegetation in the Integrated Assessment Modelling system for the Iberian Peninsula. Evaluation for wheat and Holm oak

“…This work allows estimating and comparing the risk of ozone damage on vegetation in the Iberian Peninsula (IP) and Balearic Islands through concentration-based and flux-based approaches integrating both, modelled meteorological conditions and O3 levels. Such development establishes a framework for estimating the risk of ozone impacts on vegetation under different emission/ policy scenarios according to the concentration-response and flux-response relationships derived from experimental studies (Fuhrer et al, 1997;Karlsson et al, 2004;Mills et al, 2007aMills et al, , 2011aLRTAP Convention, 2010;Pleijel et al, 2004).…”