Lichen (Xanthoria parientina) biomonitoring of trace element contaminationand air quality assessment in Livorno Province (Tuscany, Italy)

This paper deals with the biomonitoring of air in Livorno Province (Tuscany , Italy) using lichens for both quantitative monitoring of airborn metals a nd air quality assessment. On the basis of the possible sources of metal po llution in the study area, the following elements were analyzed: As, Cd, Cr , Ni, Pb, V, Zn and Hg. The small number of lichen species, the often stunt ed appearance of the specimens, and metal analysis revealed widespread atmo spheric pollution in the study area. The results indicate extensive anthrop ic impact. The highest levels of contamination were recorded for Hg, Cd, Pb , and V concentrations. Good agreement was found between bioindication and metal concentrations in lichens. The impact of anthropic activities is part icularly due to steelworks and chemical plants, combustion processes relate d to energy production and vehicle emissions. In addition to air pollution, some natural factors, such as climate, rocky shores or ozone, were assumed to affect lichen occurrence. Comparison with the Lake Orta area in norther n Italy showed Livorno Province was more contaminated by trace elements. Si milar contamination levels were found in another area of Tuscany, probably due to the geological characteristics of this region. (C) 1999 Elsevier Sci ence B.V. All rights reserved.