The assessment of lichens as bioindicator of heavy metal pollution from motor vehicles activites

Abstract

The contamination of heavy metals released by traffic activities on roadside soils and crops are important
problems in developed and developing countries for decades. An assessment of the extent of pollution in
roadside soils is a key procedure to protect their ecological function and sustainable agriculture. The objectives
of this study were to determine heavy metal contamination of roadside soils that originated from motor vehicles
through the use of eight different lichens species situated along D-950 motorway in Erzurum. The results showed
that the contamination of Pb, Cr, Cu, Cd, and Ni in roadside soils stemmed mainly from traffic activities, especially
for Pb and Cd in this study area judging by their distribution patterns and their enrichment factors. Some of the
lichen species such as Xanthoria candelaria (L.) Th. Fr., Lecanora muralis (Schreb.) Rabenh. and Xanthoria
elegans (Link) Th. Fr., present in the region can be used to monitor pollution of traffic origin and X. candelaria, in
particular, is a very good indicator of pollution of traffic origin. This kind of lichen could be an easy and costeffective
means of air pollution monitoring.