DISTRIBUTION OF CHEMICAL ELEMENTS IN SURFACE WATERS FROM THE CRNA RIVER BASIN, REPUBLIC OF MACEDONIA

An investigation of the distribution of 23 chemical elements (Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sr, V and Zn) in surface water samples from the entire basin of the Crna River, Republic of Macedonia, was carried out. In total 31 water samples were collected, from which 8 samples from the Crna River and 4 samples from four main tributaries of Crna River in the Pelagonia Valley (Blato, Prilepska Reka, Dragor and Jelaska Reka). Also, surface water samples were collected from 3 locations in the Tikves Lake, 8 locations from the Majdanska River and river of Blasnica before its inflow into the Tikves Lake and from 7 locations of the lower course of the Crna River after the dam of Tikves Lake until its inflow into the river of Vardar. Determination of the concen-tration of the investigated elements was performed by using atomic emission spectrometry with inductively coupled plasma (ICP-AES). All data obtained for the analyzed samples were statistically processed using software Stat Soft 11.0 where the descriptive statistical analysis of the value for the concentration of the elements was performed. The maps of spatial distribution of the concentration for each element and a histograms for the representation of elements with mean values of the concentrations by regions, were also prepared. The obtained results show that the concentration of investigated element are mainly followed the lithology of the region. However, higher concentrations of arsenic were found in the water samples from the river of Blasnica which is a result of anthropogenic influence from the abounded Allchar mine on the Kožuf Mountain. Also, the increased concentrations of nickel were found in the samples from the lower couse of the Crna River after the dam of Tikves Lake due to the anthropogenic influence from the ferronickel smelter plant Feni Industry, which can influence the quality parameters of surface waters.