The aim of this research was to determine how fast the level of heavy metal concentrations in the air decreases in relation to increasing distance from the source of pollution and what the influence ...area is of the zinc smelting plant which existed for 100 years in Celje. In that period it produced approximately 580,000 tons of raw Zn from sphalerite ore by the pyrometallurgical process. The production left behind a heavily contaminated area, where the concentrations of Pb and Zn in the soil can be expressed as a percentage. A model has been made on the basis of the data of concentrations of Zn and Cd in the soil and attic dust regarding the distance and direction from the source of the pollution. Because Celje lies in a basin we chose a linear model, which describes the decreasing of the concentrations of Zn and Cd only in one direction. Sampling has been conducted on the four river valleys which stretch from the source of the pollution in all four directions: north, west, south and east, up to 13 km from the source. The power function with a negative exponent was used. With the solution to the calculated functions according to the distance, we can estimate the theoretical distance when the concentrations drop to the natural background level. The range of influence of the zinc smelting plant has been estimated to be between 14 and 52 km for the presence of anthropogenic Zn in attic dust and between 9 and 14 km for the presence of anthropogenic Zn in the soil, depending on the direction from the plant. Correlations between the measured values and the ones from the model are high: from 0.75 up to 0.98.
The research shows that in the Celje area (Slovenia), the historical anthropogenical emissions are 1,712 tons of Zn and 9.1 tons of Cd. For Zn, this value represents approximately 0.3% of the total ...Zn production in that area. Close to the former zinc smelting plant, the “Zn precipitation” has been estimated to be up to 0.036 mm. The 100-year Zn production left behind a heavily contaminated area with maximum concentrations of Zn of up to 5.6% in attic dust and 0.85% in the soil, and 456 mg/kg of Cd in attic dust and 59.1 mg/kg in the soil. The calculation of historical emissions is based on the data of heavy metals concentration in the attic dust at 98 sampling points and on the data from 19 measurement sites of the weight of total monthly air deposit. The main idea behind determining past emissions is that when the weight of the deposited dust on a small area is multiplied by the concentration of the element in that area, the mass of the polluter which has been transported to the place of interest by air can be calculated. If we sum up all the weight over the whole geochemical anomaly, we get the quantity of historical emissions.
Soil samples (0 to 5 cm) from 30 locations in the Celje region, Slovenia, an area that has been subjected to severe industrial emissions of Pb and Zn, were analyzed for selected soil properties and ...subjected to a six-step sequential extraction of Pb and Zn. Phyto-available forms of heavy metals: soluble in soil solution and exchangeable from soil colloids to soil solution together accounted for 0 to 1.68% of Pb and 0 to 40.8% of total soil Zn. Most of the Pb and Zn was found to reside in less labile forms bound to carbonate (2.04 to 43.5% Pb, 3.9 to 35.1% Zn), bound to Fe and Mn oxides (0 to 16.1% Pb, 1.4 to 25.4% Zn), bound to organic matter (35.8 to 71.1% Pb, 14.8 to 56.2% Zn), and in the residual fraction (10.4 to 53.4% Pb, 14.2 to 75.3% Zn). Factor analysis and stepwise multiple regression revealed that the concentration of Pb in the proposed indicator plant, narrow leaf plantain (Plantago lanceolata) did not correlate with the measured soil properties, Pb fractionation in soil, and total soil Pb. Plant uptake of Zn, however, significantly correlated with soil pH and with the share of phyto-available forms of Zn in the soil (R
2
= 86.9). A statistically significant correlation (P<0.01) was found between the fractions of Pb and Zn carbonates and soil organic matter content (R
2
= 90.6 and 90.9, respectively); the fraction of Pb bound to organic matter and soil organic matter content (R
2
= 90.6); the residual fraction of Pb and total Pb content in soil (R
2
= 95.7); the fraction of Zn bound to Fe an Mn oxides, the fraction of Zn bound to organic matter, the residual fraction of Zn and total Zn content in soil (R
2
= 75.9, 93.2, and 87.4, respectively). Soil texture, pH, and cation exchange capacity did not affect the relative proportions of Pb and Zn forms in soil.
maps
Tyt. a whole based on sources. Tyt. Map parts in the lower left corner in the frame.
Landscape sculpture: hatching.
On the map 2 tables: in the upper left corner with a list of selected objects; ...in the lower right part with legend and text.
Verso: blanco.
mapy
Tyt. całości ustalony na podstawie źródeł. Tyt. części z mapy w lewym dolnym rogu w ramce.
Rzeźba terenu: kreskowanie.
Na mapie 2 tabele: w lewym górnym rogu z wykazem wybranych obiektów; w prawej dolnej cz. z legendą i tekstem inform.
Nad górną ramką z prawej s.: N.o 4.
Verso: blanco.
