Lichens as indicators of air pollution in urban and rural sites of Rieti (Central Italy).

The results of a research aimed to study the environmental quality in the a rea of the Rieti town (Central Italy) using the macrolichen vegetation as b ioindicator are reported. An estimation of SO, content in the atmosphere, b ased on the Hawsworth and Rose's biological scale, has been also given. The analysis of the distribution of the epiphytic lichens in five areas, from the town centre (400 m a.s.l.) to the near mountain area (1700 m a.s.l.), c onfirmed the efficiency of fruticose and foliose lichens as bioindicators a nd the low sensitivity of the crustose ones to the pollutants.