Spatial distribution of labile and total forms of copper and zinc in sediments from the Port of Gdansk

Sediment cores were collected from a number of sites in the Port of Gdansk in 1997 and 1998. The samples were segregated by depth then dried, homogenised and sieved into four grain size fractions (>2.00 mm, 2.00 - 0.063 mm, 0.063 - 0.032 mm, and 0.032 mm) Small-grained sand with a low admixture of silt predominated in all samples, whilst the amount of organie matter and water varied between samples. The 2.00 - 0.063 mm size fraction was the most abundant; and also showed the highest accumulation of trace metals. In the <2.00 mm size fraction the mean concentration of labile forms of copper was 9.06 mg kg"1 DW, while the concentration of total forms was 12.73 mg kg'1 DW. The mean concentrations of labile and total forms of zinc in this fraction were 31.79 and 46.27 mg kg"1 DW, respectively. The widest ranges of concentrations for both labile and total forms of the metals were found in the near-surface sediment layers (0-20 cm). Sediments collected from highly industrialized locations contained the highest concentrations of metals.