Functional and morphological traits of epiphytic lichens in the Western Carpathian oak forests reflect the influence of air quality and forest history

We analysed a dataset composed by the frequency of 79 epiphytic lichens recorded on 243 oaks distributed in 29 oak dominated stands of the Western Carpathians, representing areas with high environmental quality up to disturbed environments. Lichen diversity indices (based on total frequencies and on functional and morphological groups) were used as indicators of the response to air quality and forest management. The level of air quality in these categories was a function of NOx, SO2 and particulate matter. From management viewpoint the units were classified as managed (areas subjected to periodic logging) and semi-natural (which currently have the status of National Nature Reserve and where eventual management practices date back to the history). The results showed that higher environmental levels of pollution were associated to the decrease of fruticose and in general pollution sensitive species, while low environmental levels of pollution were associated to the diffusion of common nitrophilous lichens as well as to a higher share of fruticose and in general pollution sensitive species. As far as forest management is concerned, a higher share of fruticose and sensitive species was associated to semi-natural and natural stands, whereas a higher share of foliose (pioneer and tolerant) species was associated to the managed stands.