title: Influences of elevated ozone and carbon dioxide in growth responses of lowland hay meadow mesocosms.
abstract: We studied the effects of relatively low levels of O(3) (40-50 ppb) and CO(2)-enrichment (+100 ppm) on a northern European lowland hay meadow during the summers 2002-2004 using open-top chambers (OTCs) and ground-planted mesocosms. Ozone reduced the aboveground biomass of the community (up to 40%), and four out of seven species (Campanula rotundifolia, Fragaria vesca, Trifolium medium, Vicia cracca) showed either significant growth reduction and/or visible injuries under elevated O(3). However, the reductions in aboveground biomass were not reflected as changes in the dominance of different functional groups or in the total community root biomass. Elevated CO(2) did not amend the detrimental effects of O(3) on aboveground biomass. Elevated CO(2) alone had only minor effects. An O(3)-induced reduction in the aboveground biomass and N pool of the community are likely to have important consequences in the nutrient cycling of the ecosystem.
authors.affiliation: Department of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1, P.O. Box 65, 00014 Helsinki, Finland. kaisa.koivisto@helsinki.fi <kaisa.koivisto@helsinki.fi>
authors.forename: Kaisa
authors.initials: K
authors.lastname: Rämö
authors.forename: Teri
authors.initials: T
authors.lastname: Kanerva
authors.forename: Suvi
authors.initials: S
authors.lastname: Nikula
authors.forename: Katinka
authors.initials: K
authors.lastname: Ojanperä
authors.forename: Sirkku
authors.initials: S
authors.lastname: Manninen
mesh_terms: D000383:Agriculture; D000393:Air Pollutants / Q000009:adverse effects*; D018533:Biomass; D002245:Carbon Dioxide / Q000633:toxicity*; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D005387:Finland; D017752:Greenhouse Effect; D009584:Nitrogen / Q000378:metabolism; D010126:Ozone / Q000633:toxicity*; D063245:Plant Development; D010944:Plants / Q000378:metabolism; D006109:Poaceae / Q000254:growth & development / Q000378:metabolism
chemical_list: D000393:Air Pollutants; D002245:Carbon Dioxide; D010126:Ozone; D009584:Nitrogen