Acta Facultatis Ecologiae - Technická univerzita vo Zvolene

11ACTA FACULTATIS ECOLOGIAE, 16: Suppl. 1, 11– 15 Zvolen (Slovakia), 2007HEAVY METALS IN SOILS IN THE REGIONSWITH ENVIRONMENTAL LOAD IN MIDDLE SPIŠViliam Carach − Monika Vaľková – Ľubica KozákováTechnická univerzita v Košiciach, Fakulta BERG, Letná 9, 042 00 Košice, e-mail: viliam.carach@tuke.sk, monika.valkova@tuke.sk, lubica.kozakova@tuke.skABSTRACTCarach V., Vaľková M. & Kozáková Ľ. Heavy Metals in Soils in the Regions with EnvironmentalLoad in Middle SpišThe soil samples from middle Spiš were collected and analyzed for releasable, mobilizable and mobileforms. Contents of heavy metals were judged according to determination of the MP SR no. 531/1994– 540. Heavy metal contents were increased in comparison with highest acceptable concentration (A 1) andin a few samples indication values (B). Mobile fraction for lead was increased in comparison with copperand zinc in order: Pb > Zn > Cu. In the case of mobilizable forms there was the following order: Cu >> Zn > Pb.Key words: contamination of soils, bioavailable form of heavy metals, copper, lead, zincINTRODUCTIONHeavy metals in soils are important problem.They are situated in the old environmentally loadareas which used to be mining ones. Heavy metalscan exist in variable forms. These forms have animpact on mobility and accessibility of plants. It isimportant to know the content of accessible formson the part of advisement potentional treath. Theseforms determine risk of mobilization and transferin other components.Heavy metals in plants and their transfer to thefood web will influence their bioavailability whichdepends on properties of soils, pH, cationexchangeablecapacity and redox potential. Bioavailabilityof Zn, Pb, Cd decreases if pH of soils increases.Reduction of availability of metals is influenced byhigher adsorption and precipitation in neutral andalkaline environment [1, 2].Wang found out 30–60 multiple increase of Cu,Cd, Pb and Zn contents in soils and plants in coppermining area in compare with control [3]. This increasewas found with studies of chemical forms ofheavy metals in soils. Contents of heavy metals inclover hint as a positive signification of correlationwith their exchangeable and organic forms in soils.Also these contents hint as a negative significationof correlation with Fe and Mn oxides and carbonateforms and they hint as no correlation with residualforms.The region of middle Spiš was classified asthe loaded region and hygienically badly followingenvironmental regionalization. Dominant contaminantsare heavy metals in this classification ofcomponents of the environment. Mining operationswith following processing of complex metals andcopper ores left negative effects in this region [4].The region has three general locations of contamination:the industrial locality Rudňany, Krompachyand Spišská Nová Ves. Overload of limiting valuesof Hg, Cu, Zn, As, Cd and Pb was found in soils.Heavy metals in soilsLead in soils belongs to less mobile elements,especially when is bounded to carbonates and disulphates.Hydrosulphide is introduced as an indissoluiableform whose occurence is little likely(except soils over ores) [5].