Farkas E, Lőkös L, Verseghy K: Lichens as indicators of ... (1985)

Farkas Edit, Lőkös László, Verseghy Klára
1985
Lichens as indicators of air pollution in the Budapest Agglomeration. I. Air pollution map based on floristic data and heavy metal concentration measurements.
Acta Bot. Hung. 31: 45-68.
Summary: 

The recent distribution of lichens in Budapest was examined and heavy metal concentrations in two lichen species were measured to indicate air pollution zones of Budapest. A lichen zone map was drawn according to the distribution of epiphytic lichen species. This map was compared to a sulphur dioxide zone map, to the distribution map of lichens compiled about 70 years ago and to old and recent maps of the built-up areas. The effect of climate and substrate type upon lichens was also investigated. Because of the abscence of epiphytic lichens in the extensive desert zone (downtown Budapest), transplanted Hypogymnia physodes and Cladonia convoluta samples were taken at 50 points in order to determine the concentration of accumulated heavy metals (Pb, Cd, Mn, Zn).