Speciation of elements in lake sediments investigated using x-ray fluorescence and inductively coupled plasma atomic emission spectrometry

Radioisotope-excited energy-dispersive x-ray fluorescence (EDXRF) analysis and inductively coupled plasma atomic emission spectrometry (ICP-AES) mere used to investigate the speciation of elements in sediment samples collected from a peat bog in Hungary. Lake and bog sediments are a mixture of allogenic material (clastic mineral particles resulting from erosion of the catchment soils or from dust) and authigenic components (deposited directly from aquatic solution through biological uptake or chemical sorption, biochemically precipitated carbonate minerals, Fe and Mn oxides, oxyhydroxides, sulphides, sulphates, phosphates, etc.). After removing the authigenic fraction by wet digestion, element concentrations in the acid insoluble residue were determined by XRF and those in the authigenic part by ICP-AES. On the basis of chemical composition, the sediment sequence was divided into three zones reflecting different environmental regimes during sediment accumulation. Allogenic and authigenic species of elements provided relevant information on environmental processes which changed the soil and vegetation in NE Hungary during the early postglacial. (C) 1988 John Wiley & Sons, Ltd.