A retrospective study using epiphytic lichens as biomonitors of air quality: 1980 and 1996 (Tuscany, central Italy)

The results of a retrospective study (data of 1980 and 1996) performed in the Chianti Region (Tuscany, central Italy) using epiphytic lichens both as sensitive indicators and accumulative monitors are presented. Floristic data, particularly the presence of numerous species known to be sensitive to air pollutants, indicated that air quality in the study area remained fairly good throughout this 16-year period, and may even have improved. Accumulation of trace elements in Parmelia caperata thalli collected in 1980 and 1996 supported this conclusion, with concentrations similar or even lower than those previously reported in other unpolluted areas of Tuscany. Most elements showed a marked decline from 1980 to 1996, suggesting that in the last years, the study area was subjected to a lower load of metal air pollution. Sulphur was the only element showing higher concentrations in 1996, probably due to the increased use of S-based pesticides in vineyards.