The effect of intensive traffic on soil and vegetation risk element contents as affected by the distance from a highway

The potential effect of intensive traffic on detrimental element contents in soil and vegetation was investigated in the vicinity of a selected section (1 km) of a highly frequented highway as affected by the distance from the roadway (1 m, 35 m, and 70 m). Aqua regia and 0.11 mol/L acetic acid soluble contents of As, Cd, Cr, Cu, Mo, Ni, Pb, and Zn in soils and total contents of these elements in the aboveground biomass of Achillea millefolium L. (Asteraceae) and Vicia cracca L. (Fabaceae) were determined. The main physicochemical parameters of the soils were determined, as well. The element contents did not exceed the maximum permissible limits for both soils and plants (evaluated as fodder crops). Moreover, high variability of element contents in soils and plants, and soil characteristics did not allow us to estimate the rate of potential effect of road traffic. Some of the elements however tightly related to atmos pheric deposition caused by traffic such as Pb and Zn tended to decrease in soils with increasing distance from the roadway.