EVALUATION OF CHEMICAL-PARAMETERS IN ALIAKMON RIVER IN NORTHERN GREECE .2. DISSOLVED AND PARTICULATE HEAVY-METALS

A two-year survey on the water quality characteristics of Aliakmon riv er in northern Greece is described. Heavy metals (Pb, Cd, Cr, Cu, Mn a nd Fe) were determined in the dissolved fraction, as well as in two pa rticulate fractions, labile and residual, separated after a two-step s equential extraction procedure. The partitioning of metals between dif ferent fractions was examined at various sampling sites along the rive r. Variations observed were related to the geology of the transected a rea and the influence from anthropogenic sources (mainly municipal eff luents). Statistical analysis of variance of metal partition coefficie nt showed significant differences between sampling periods, while insi gnificant ones between sampling sites. Factor analysis of analytical d ata yielded four factors that were interpreted as natural, anthropogen ic, geological and run-off contributions.