Relationships between lichen community composition and concentrations of NO2 and NH3.

The relationship between different features of lichen communities in Quercus robur canopies and environmental variables, including concentrations of NO(2) and NH(3) was investigated. NO(2) concentration was the most significant variable, it was positively correlated with the proportion of lichen cover comprising nitrophytes and negatively correlated with total lichen cover. None of the lichen community features were correlated with NH(3) concentrations, which were relatively low across the site.