Impact of Historical Mining and Metallurgical Technologies on Soil and Sediment Composition Along the Ibar River

This study systematically investigates soil and stream sediment along the 165 km Ibar River to examine the origin and transfer of pollutants. The research focuses on the environmental impact of long-term mining and irregular waste management, as well as natural enrichment related to weathering processes. A comprehensive sampling campaign was conducted, collecting 70 samples from 14 locations. At each location, samples of river sediment, floodplain soil (0–5 cm and 20–30 cm depths), and river terrace soil (same depths) were collected. The contents of 21 elements (Ag, Al, As, B, Ba, Ca, Cd, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, V, and Zn) were determined using inductively coupled plasma atomic emission spectrometry (ICP-AES). Analysis of Variance (ANOVA) was performed to identify statistically significant differences in element contents between defined zones, sampled materials (river sediments, floodplain soils, and river terrace soils), and sampled soil horizons (topsoil, 0–5 cm, and subsoil, 20–30 cm). Multivariate analysis, including correlation coefficient, cluster analysis, and principal component analysis, revealed two distinct groups of elements with highly significant correlation coefficients (r > 0.7). The first group, comprising Ag, As, Cd, Cu, Mn, and Zn, indicates anthropogenic enrichment, likely resulting from mining and smelting activities in the middle flow of the Ibar River (The Mining and Metallurgical Complex Trepča). The second group, consisting of Cr, Mg, and Ni, suggests enrichment related to the weathering of elements from the ophiolite zone in the lower Ibar River. The study found high enrichment ratios of toxic elements like arsenic, cadmium, lead, and zinc, particularly in stream sediments and floodplains. Notably, arsenic contents exceeded European averages by up to 57 times in stream sediments, posing a significant environmental concern due to its high content.