GEOCHEMICAL BACKGROUND HEAVY METALS AND SPATIAL DISTRIBUTION OF STREAM SEDIMENTS IN DUKAGJINI BASIN

Heavy metal concentrations of stream sediments from Dukagjini Basin were investigated to evaluate the geochemical distribution of selected elements. Dukagjini basin together with the Kosovo Basin represents the largest sedimentary basins in Kosovo. Tertiary basin of Dukagjin, with an area of 1700 km2 is located in the western part of Kosovo. The soils in this basin are used mainly for agriculture. The aim of this paper is to determine threshold values using statistical methods that can explain their spatial distribution. Stream sediment geochemistry can be used to quantify natural geochemical baselines and anthropogenic effects. A total of 574 stream sediment samples were analyzed for arsenic (As), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn). The mean concentrations of heavy metals are in decreasing order as follows: Mn > Cr > Ni > Zn > Cu > Pb > As. Analysis of samples has shown no evidence of Hg content. The results show that the elements Cr and Ni exceed the threshold values according to the method Median and Median Absolute Deviation (Median+2MAD) for 155 respectively 153 samples. Spatial distribution for Cr and Ni reflect the elevated geochemical background of the wider area due to the presence of ophiolites therefore it may be considered their geogenic origin. This work is important to register the current levels of metals so that any change in concentration can be monitored and managed.