Emelyanov E.M., Gulbinskas S., Suzdalev, S.
Biogenic components and trace elements in the sediments of
river mouths and accumulation areas of the Curonian Lagoon (south-eastern
Baltic Sea)
Abstract. Contribution of the Neman (Nemunas) River
including the arms Atmata, Skirvytė and Razliv, as well as Matrosovka and Deima
rivers to the general enrichment of the Curonian Lagoon with biogenic
components and chemical elements is reflected in the composition of surface
sediments accumulating in the river mouths. Other part of chemical substances
are absorbed by the finest particles and reaches accumulation areas of the
lagoon in the south-western and central parts. Results from the study have
shown the prevalence of terrigenous and biogenic-terrigenous sediments in the
mouths of small rivers. Highest average values of biogenic components
(31.46–38.87% of CaCO3; 0.63–1.03% of N; 0.07–0.1% of P) are observed in the
accumulation areas of the coarse silt and fine silty mud. Same areas are
characterized by the increased amounts of potentially hazardous metals (Cd, Cr,
Cu, Ni, Pb, Zn). Results from this study have shown considerable enrichment of
sediments with arsenic. In most places average contents of this metalloid are
well above the geochemical background values, determined for the south-eastern
part of the Baltic Sea. Absolutely highest values of arsenic (91–93 mg/kg)
suggesting presence of serious contamination sources were determined in the
south-eastern part of the lagoon, adjoining the mouth of small Matrosovka
River.