title: Sources of errors in assessing ozone visible symptoms on native vegetation.
abstract: This paper aims to identify the problems regarding the evaluation of ozone (and ozone-like) symptoms, by examining the results of the 4th UN/ECE ICP-Forests Intercalibration Course for the assessment of ozone-induced visible symptoms. Trees, shrubs and herbaceous species were evaluated in a tree nursery, at Lattecaldo (Switzerland) and under open field conditions at Moggio (Italy). The main findings were: (i) the most expert surveyors tended to be grouped in the same cluster and, during the field exercises, they tended to assess in a more conservative manner compared to the less trained participants; (ii) the agreement was greater in assessing the absence rather than the presence of symptoms; (iii) typical interveinal stippling on the upper leaf surface was more accurately evaluated than discoloration; (iv) uncertainties resulted mainly for species which showed greater variability in their symptom manifestation, and for certain herbaceous species.
authors.affiliation: Department of Plant Biology, University of Florence, Piazzale delle Cascine 28, 50144 Florence, Italy. filippo.bussotti@unifi.it
authors.forename: Filippo
authors.initials: F
authors.lastname: Bussotti
authors.forename: Marcus
authors.initials: M
authors.lastname: Schaub
authors.forename: Alberto
authors.initials: A
authors.lastname: Cozzi
authors.forename: Giacomo
authors.initials: G
authors.lastname: Gerosa
authors.forename: Kristopher
authors.initials: K
authors.lastname: Novak
authors.forename: Christian
authors.initials: C
authors.lastname: Hug
mesh_terms: D017753:Ecosystem; D004777:Environment; D004784:Environmental Monitoring / Q000379:methods; D015588:Observer Variation; D010083:Oxidants, Photochemical / Q000633:toxicity*; D010126:Ozone / Q000633:toxicity*; D010641:Phenotype; D010935:Plant Diseases / Q000139:chemically induced; D018515:Plant Leaves / Q000187:drug effects; D010944:Plants / Q000187:drug effects*; D011361:Professional Competence; D011786:Quality Control; D012621:Seasons; D014197:Trees / Q000187:drug effects
chemical_list: D010083:Oxidants, Photochemical; D010126:Ozone