The combined influence of SO2 and heavy metal-containing particulates on beans, carrots and parsley

The effects of various concentrations of air pollutants on crop losses were investigated. Parsley, bean and carrots were fumigated using SO2 in concentrations ranging from 0.35 mg m(-3) (0.13 ppm) to 4.5 mg m(-3) (1.7 ppm) with and without lead/zinc/cadmium-containing particulate matter. It was concluded that a long-term exposure to low levels of SO2, even without visible plant injuries, resulted in more significant crop losses than short-term, high concentrations.Measurements of root and leaf weight in carrot and parsley fumigated in exposure chambers with SO2 show that the ratio of root to leaf weight is dependent on the type and concentration of pollutants. This result leads to the conclusion that a mathematical model describing the above phenomena might be an useful tool in the assessment of crop losses due to known concentrations of air pollutants during the growth period.