Geospatial distribution of heavy metals in sediments of water sources in the Drini i Bardhë river basin (Kosovo) using XRF technique

Heavy metals in sediments may have significant effects on environment and human health and can provide basic information for risk assessment of environmental health. The aim of the current work is to extend our first research on geochemical and contamination status of sediment fraction < 63 µm in Drini i Bardhë watershed and thus extend the overall knowledge about geochemistry of water sources sediments in Kosovo, which is up to now poorly investigated. The heavy metal concentrations were determined using X-ray fluorescence (XRF) technique. Spatial distribution maps were created and recorded, in terms of these heavy metals concentrations as contribution to heavy metal pollution in sediments through geographical information systems techniques. By comparing the concentrations of heavy metals in sediment of water sources with the existing criteria for sediment quality, it was found that eight samples in river basin of Drini i Bardhë were significantly polluted. These exceeded mass concentrations of some heavy metals in sediment in those areas were directly impacted from geological constitution of rocks: clastic, alluvium, proluvium, glacigene, calc tufa/travertine and lake sediments. The following elements showed concentrations in studied sediments above threshold causing toxic effects (maximal measured concentrations in parenthesis): Cd (79.4 ppm), Ag (54.4 ppm), As (74.03 ppm), Zn (3481.88 ppm), Cu (171.93 ppm), Ni (785.81 ppm), Co (695.94 ppm), Fe (17.06%), Mn (4208.84 ppm) and Cr (743.47 ppm). Some of those concentrations are very high according to existing standards. In statistical terms the mean concentrations of the studied heavy metals have decreased in order: Fe > Mn > Zn > Sb > Ni > Sn > Cu > Rb > Pb > Cd > Ag. In study period, Sb showed high significant positive relationship with Sn (0.90), Cd (0.78), Ag (0.70), and Fe (0.73). Sn showed high significant positive relationship with Cd (0.79). Cluster analysis of R-mode showed that Fe has the closest association with Mn. After that Mn has the closest association with Zn and they form one branch of the dendrogram. The geospatial distribution maps of heavy metals in sediment fraction < 63 µm from the studied region were constructed, which can serve as a baseline for planning of future monitoring and research, which are encouraged.