title: Biogenic volatile organic compound emissions along a high arctic soil moisture gradient.
abstract: Emissions of biogenic volatile organic compounds (BVOCs) from terrestrial ecosystems are important for the atmospheric chemistry and the formation of secondary organic aerosols, and may therefore influence the climate. Global warming is predicted to change patterns in precipitation and plant species compositions, especially in arctic regions where the temperature increase will be most pronounced. These changes are potentially highly important for the BVOC emissions but studies investigating the effects are lacking. The aim of this study was to investigate the quality and quantity of BVOC emissions from a high arctic soil moisture gradient extending from dry tundra to a wet fen. Ecosystem BVOC emissions were sampled five times in the July-August period using a push-pull enclosure technique, and BVOCs trapped in absorbent cartridges were analyzed using gas chromatography-mass spectrometry. Plant species compositions were estimated using the point intercept method. In order to take into account important underlying ecosystem processes, gross ecosystem production, ecosystem respiration and net ecosystem production were measured in connection with chamber-based BVOC measurements. Highest emissions of BVOCs were found from vegetation communities dominated by Salix arctica and Cassiope tetragona, which had emission profiles dominated by isoprene and monoterpenes, respectively. These results show that emissions of BVOCs are highly dependent on the plant cover supported by the varying soil moisture, suggesting that high arctic BVOC emissions may affect the climate differently if soil water content and plant cover change.
authors.affiliation: Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Universitetsparken 15, DK -2100 Copenhagen E, Denmark; Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK -1350 Copenhagen K, Denmark.
authors.forename: Sarah Hagel
authors.initials: SH
authors.lastname: Svendsen
authors.affiliation: Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Universitetsparken 15, DK -2100 Copenhagen E, Denmark; Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK -1350 Copenhagen K, Denmark.
authors.forename: Frida
authors.initials: F
authors.lastname: Lindwall
authors.affiliation: Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Universitetsparken 15, DK -2100 Copenhagen E, Denmark; Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK -1350 Copenhagen K, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Michelsen
authors.affiliation: Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Universitetsparken 15, DK -2100 Copenhagen E, Denmark; Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK -1350 Copenhagen K, Denmark. Electronic address: riikkar@bio.ku.dk.
authors.forename: Riikka
authors.initials: R
authors.lastname: Rinnan
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001110:Arctic Regions; D057231:Climate Change; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D029791:Ericaceae / Q000254:growth & development; D006116:Greenland; D027824:Rosaceae / Q000254:growth & development; D032108:Salix / Q000254:growth & development; D012987:Soil / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000032:analysis*; D014867:Water / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D012987:Soil; D055549:Volatile Organic Compounds; D014867:Water
keywords: BVOC; CO(2) exchange; Greenland; isoprene; tundra; vegetation composition