01276nas a2200169   4500008003900000245007500039210006900114300001200183490000800195520074100203100001400944700001500958700001600973700001500989700001601004856008601020       2007                          d00aDiversity and sensitivity of epiphytes to oxides of nitrogen in London0 aDiversity and sensitivity of epiphytes to oxides of nitrogen in   a299-3100 v1463 aThis 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.1 aDavies, L1 aBates, J W1 aBell, J N B1 aJames, P W1 aPurvis, O W  uhttps://www.apis.ac.uk/diversity-and-sensitivity-epiphytes-oxides-nitrogen-london