LICHENS AS LONG-TERM BIOMONITORS OF AIR-QUALITY IN CENTRAL ITALY

The results of a long-term study (data of 1978 and 1993) performed in central Italy using epiphytic lichens both as indicators and monitors (accumulators) are presented. Floristic data showed that air quality i n the study area did not change markedly in this 15-year period and is currently fairly good. Similarly, the concentrations of trace element s in Parmelia caperata thalli showed no substantial change, with value s similar to those in lichens of unpolluted areas. The concentration o f Cs-137 in P. caperata and Lobaria pulmonaria thalli doubled after th e Chernobyl accident, but was low compared to other European areas.