Effect of air pollution on photosynthesis-A study of its effect on oxygen evolution

Abstract

This paper deals with the effect of urban air pollution on oxygen evolution by common tropical avenue tree species growing along three important traffic corridors in the capital city of Delhi. Oxygen evolution was measured using Clark-type Hansatech oxygen electrode (U.K.) A marked reduction in oxygen evolution was observed in five species of tropical avenue trees, viz., Azadirachta indica A.Juss, Alstonis scholaris R.Br. Ficus religiosa Linn., Ficus benghalensis Linn. and Morus alba Linn. growing along three important traffic corridors in the capital city of Delhi. Reduction in oxygen evolution was found to be related to the intensity of air pollution resulting from growing automobile traffic. In respect of oxygen evolution, Ficus religiosa was found to be the most sensitive, while Alstonia scholaris was relatively tolerant to roadside automobile pollution. The results of this study suggest that sensitivity of oxygen evolution to air pollution can be an important criteria for selecting avenue trees for road side plantation along high traffic corridors in urban areas and for raising green belts in and around industrial complexes.