Ecology, Environment and Conservation Paper

HIGHER PLANTS A.S J)ORNON ITORS OF AUTOMOBILE POLLUTION

H. Ramakrishnaiah and R.K. Somashekar

Abstract

This paper describes air pollution tolerance among roadside plants exposed to varying degrees of traffic pollution. Parameters such as chlorophyll, ascorbic acid, pH of the leaf extract and relative water content were used to obtain air pollution tolerance index (APTI).The observed significant reduction in total chlorophyll, ascorbic acid and relative water content showed inverse relationship with traffic density.Similarly, the pH followed an exponential decrease with increase in traffic pollution and drifted towards the acidic range. Due to higher reduction in APTI over control coun- terparts, Vernonia rinerea, Lagoscea mollis,Tridax procumbens,Vinca rose°, Euphorbia hirta,Amaranthus spinosus and Ageratum conyzoides are considered as sensitive species to automobile emission. Conversely Pongamia pinnata, Polyalthia longifolia, Bauhinia purp urea, Portulaca oleracea and Cornphrena celosioides are regarded as relatively resistant species.The utility of APTI bio analysis is discussed.