title: Diversity and sensitivity of epiphytes to oxides of nitrogen in London.
abstract: This study investigated the distribution and diversity of epiphytes in London in relation to NO(x) using fine-scale atmospheric dispersion modelling. The survey recorded over 3000 epiphytes from 334 trees (Fraxinus excelsior) representing 74 lichen, 14 moss, 7 fungal and 3 algal species. There was a significant inverse relationship between diversity and NO(x). Diversity declined where NO(x) exceeded 70 microg m(-3) and NO2 exceeded 40 microg m(-3), suggesting a phytotoxic effect. However, there was a significant positive relationship between NO(x) and lichen abundance due to the ubiquitous distribution of pollution tolerant species, mainly associated with eutrophication. A scale of lichen sensitivity to NO(x) has been derived.
authors.affiliation: Centre for Environmental Policy, South Kensington Campus, Imperial College London, London SW7 2AZ, UK. linda.davies@imperial.ac.uk
authors.forename: L
authors.initials: L
authors.lastname: Davies
authors.forename: J W
authors.initials: JW
authors.lastname: Bates
authors.forename: J N B
authors.initials: JN
authors.lastname: Bell
authors.forename: P W
authors.initials: PW
authors.lastname: James
authors.forename: O W
authors.initials: OW
authors.lastname: Purvis
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D044822:Biodiversity; D044002:Bryophyta / Q000502:physiology; D004784:Environmental Monitoring / Q000379:methods; D005658:Fungi / Q000502:physiology; D008011:Lichens / Q000502:physiology*; D008131:London; D009569:Nitric Oxide / Q000633:toxicity; D009585:Nitrogen Dioxide / Q000633:toxicity; D009589:Nitrogen Oxides / Q000633:toxicity*; D052638:Particulate Matter / Q000633:toxicity; D011891:Rain; D013696:Temperature; D014197:Trees / Q000469:parasitology; D014507:Urbanization
chemical_list: D000393:Air Pollutants; D009589:Nitrogen Oxides; D052638:Particulate Matter; D009569:Nitric Oxide; D009585:Nitrogen Dioxide