Heavy metal pollution of forest soils affected by the copper industry

The study was carried out on forest soils in the vicinity of a copper ore tailings facility and a copper smelter in Lower Silesia, Poland. Soil and litter samples were collected in the surroundings of the tailings facility under pine stands different in age (50, 18 and 11 years old) and under poplar stands (same age as the pine stands) located at an increasing distan-ce from the copper smelter (0.5 km, 1.5 km and 2.1 km). The purpose of the study was to describe the effect of copper mining and smelting on forest soils. The following were de-termined in the collected soil and litter samples: pH in distilled water electrometrically with a pH meter and total concentrations of Cu, Zn and Pb after digestion with perchloric acid (1:10) using the ICP-ES technique. Very high pH values were found in all organic hori-zons, which can evidence the alkalizing effect of dusts from the objects. In all the forest soils, the highest total concentrations of all the analyzed elements were found in humus layers, decreasing in deeper horizons of the soil profile. The total concentration of Cu, Pb and Zn was much higher in forest soils under poplar stands in the vicinity of the copper smelter. The concentration of all the elements decreased rapidly with the distance from the smelter. The concentration of Cu, Pb and Zn was higher than found in the vicinity of the objects on the arable soils. This can indicate a secondary rise in heavy metal concen-tration in the topsoil caused by the presence of a tree stand.