Some physical and biochemical effects of automobile exhaust polution on common road-side plants in Karachi, Pakistan

The effects of vehicle exhaust pollution on leaf composition of some common road-side plants of Karachi were examined. Leaf samples from polluted locality were often chlorotic and with the deposited soot. Significantly higher frequencies of clogged and partially clogged stomata [with particulate matter] were found in the leaves from air-polluted locality as compared to those from unpolluted locality. Air pollution remarkably decreased the level of total chlorophyll, chlorophyll-a and ethanol soluble carbohydrate content as compared to the control. The lead content of leaf samples from the polluted locality was significantly higher