Does the traffic flow affect the lichen diversity? A case study from the Novohradské hory Mts, Czech Republic
Abstrakt
Diversity of epiphytic lichens growing on trees with high (European ash, Norway maple) and low (sycamore) bark buffer capacity against acidification was assessed along motorways with different traffic intensities in the Novohradské Mountains, Czech Republic, to test the effect of traffic flow on the lichen richness. Twenty five plots were classified into four classes with low, moderate and moderate to high diversity according to the lichen diversity index.
Lichen frequency was significantly correlated with five factors (CCA, CANOCO). Main factors influencing lichen diversity were climatic, microclimatic, geographical, and substrate conditions rather than traffic intensity.
Nevertheless, the traffic flow influenced significantly and positively the richness of lichens growing on trunks towards roads for European ashes. Probably, bark pH increased due to vehicle-related compounds and supported the progress of neutrophytic and nitrophytic lichens.
The occurrence of acidophytic lichens in all plots indicated a decreased bark pH in relation to the previous acid regime. However, neutrophytic and nitrophytic species prevailed in these plots.
Parmelia sulcata and Amandinea punctata were the commonest species. Therefore, the lichen community studied reflects contemporary conditions of eutrophication, which is indicated by an increasing number of nitrophytic lichens, rather than by acidification.