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.