engleski

Mercury in the stream and overbank sediments of the Žumberak area (Northwestern Croatia)

Mercury together with other trace elements were analysed in stream and overbank sediments of low- to medium-order drainage basins from Žumberak and Samoborsko Gorje region. The mean regional geochemical background level for mercury concentration in stream sediments and overbank sediments is 40 ng/g and 62, 5 ng/g, respectively. The extreme mercury concentration values are estimated in stream and overbank samples of Rudarska Gradna catchment. The analyses of the samples from the overbank profiles in this catchment show large vertical and lateral variations in chemical composition. The high concentrations of Hg in the profiles samples correlate with high concentrations of Cu, Pb, Ba, As, Cr and Fe and are a consequence of sulphide-barite mineralisation and historical copper and iron ore mining. The lack of correlation between Hg and organic carbon or phyllosilicates indicates physical weathering mechanisms and mechanical dispersion of mercury that contributes to the total flux of mercury in this region. Highly contaminated sediments might become an important source of Hg.

mercury; soil; overbank and stream sediments; pollution; Žumberak

Rad je kao poster prezentiran na skupu 7th International Conference on Mercury as a Global Pollutant, održanom od 27.06.-02.07.2004., Ljubljana, Slovenija.