Toxic metal pollution of aquatic ecosystems of European Union nature protection areas in a region of intensive agriculture (Lake Gopło, Poland)

Abstract The paper presents the results of research into toxic metal concentrations in surface layer bottom sediments Lake Gopło. objectives were to identify levels and spatial variability Cu, Pb, Cd, Zn, Ni, Cr, As Hg concentrations, their potential sources determinants pollution levels. Metal contamination was assessed using geoaccumulation index (Igeo), load (PLI) ecological risk (RI). Chemometric methods (Pearson correlation, principal component analysis (PCA) cluster (CA) used determine relationship between sampling sites metals, thereby identifying contamination. found that grain-size composition, carbonate content organic matter Gopło are all characterised by low diversity. Therefore, lithological features not a major factor metals. It great majority samples above regional geochemical background indices (Igeo, PLI, RI) indicate degree is slight central southern parts lake high northern part. chemical showed differ little shares individual This provides evidence that, as well geogenic sources, presence can be associated with non-point related agricultural activities atmospheric (mainly products fossil fuel combustion). higher metals (especially Cr Hg) part influenced supply industrial communal pollutants from lakeside town Kruszwica. A limiting migration towards south lake’s morphology lake, which hinders water exchange rest lake.