ntegrated geochemical assessment of sediments from Plungė Municipal sewage outfall and sediments from Mažoji Sruoja Stream, Lithuania

Modern river sediments are complex systems of mechanical, mineral and chemical composition that are sensitive to changes in the physical and chemical conditions of the surrounding environment. Thus, more complex studies on the organic matter, grain-size fractions, chemical and mineralogical composition of the surrounding soil and sediments are necessary for the reliable interpretation of results. The composite samples from the Plungė town sewage outlet and the Mažoji Sruoja River of topsoil and stream sediments were studied. The major goal of the study was to evaluate the contamination of topsoil and stream sediments. The mineralogical, grain-size fraction, organic matter and chemical composition of topsoil and stream sediments were determined. The results obtained have revealed that none of the topsoil samples were contaminated. Some of the elements like Cu, Pb, Zn, Cr, As and Mo in stream sediments have values of the coefficient of concentration exceeding 1 and could be considered as potential contaminants. However, there was no any strong relationship between organic matter, clay, silt particles and chemical composition.