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and institutions located mainly in the town center also appear as potential sources of
air pollution in the town. Household fireplaces which use wood and coal as firewood
are also present during the winter months. Car exhaust gases are also air pollutants,
because the bulk of the atmospheric releases of nitrogen oxides, carbon monoxides,
hydrocarbons, and lead compounds originate from cars.
4.5.3.3 Prolom Spа Cаse Study (Cаse 2)
The investigated area of Prolom Spa is located in the lichen “normal” zone of air
quality indication (Fig. 4.7). A more detailed presentation of the investigated area
shows the division of the “normal” zone into three subzones – А 1 , А 2 , and А 3 . The
first subzone (А 1 ) is characterized by points 3, 7, 9, 10, 11, 13, 14, and 15 which are
distinguished by the lowest values of IAP (from 40 to 45) in relation to other investigated points in this area. The second subzone (А 2 ) is characterized by points 1, 2,
Fig. 4.6 The spatial distribution of the different indication zones of air quality in Kuršumlija (A,
lichen “normal” zone; B, “struggle” zone (B 1 “outer struggle” zone and B 2 “inner struggle” zone);
and C, “lichen desert” zone)
4 Lichens as the Main Indicator in Biological Monitoring of Air Quality