MONITORING OF AUTO EXHAUST POLLUTION BY ROADSIDE PLANTS

The changing levels of SO2 and Pb in the air and vegetation, along ten road transections of Lucknow city (having varying traffic densities) have been investigated, with a view to authenticate a possible correla tion between SO2 and Pb concentration in air and sulphate and lead acc umulation in the foliage of avenue trees. The study showed that the ro ad transection at Alambagh (traffic density 4835 for 2h) revealed the highest level of pollutants (SO2, 202 mu g m(-3); SPM, 1080 mu g m(-3) ; and lead, 2.96 mu g m(-3), 2 h average) in air, as well as in the fo liage of plants, whereas the road stretches with less traffic density correspondingly showed lower levels of pollutants. Pb and sulphate in leaves were found to be positively correlated with Pb and SO2 pollutio n in the air. Results suggest that Dalbergia sissoo and Calotropis pro cera are the ideal plant species to monitor as indications of Pb and S O2, respectively, in the air.