Lichen-bags as a biomonitoring technique in an urban area

Abstract

The suggested work presents the first application of the lichen-bags technique in the city of Plovdiv (Bulgaria). Plovdiv was pointed as one of the most polluted cities in Europe for 2008 by National Institute of Statistics of Italy (ISTAT, 2011). The study was carried out to estimate the air quality in the areas with high traffic activity, industrial and suburban zones by means of lichens. For this purpose, the concentrations of 21 chemical elements (Al, As, Ca, Cd, Cr, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, S, Sr, U, V and Zn) were investigated using Pseudevernia furfuracea (L.) Zopf. samples in bags, which were exposed at 4 different sites in the city of Plovdiv. The elements Na, Mn, Cu, Zn and Sr increased significantly their concentrations in the lichen-bags, whereas K, S and Cd decreased theirs in comparison with the unexposed lichenized fungi. Highest values of RAF (relative accumulation factor) were found for Na (3.49), Zn (2.92) and Cu (3.33).