M. Weisz et al., Fractionation of elements in sediment samples collected in rivers and harbors at Lake Balaton and its catchment area, MICROCHEM J, 67(1-3), 2000, pp. 207-217
A monitoring system has been developed to characterize the water quality of
Lake Balaton. Sediment samples were collected in rivers and harbors around
the lake and its catchment area. A modified four-step sequential leaching
procedure was applied for determination of the distribution of elements. Th
e fractions were: (1) exchangeable/bound to carbonate; (2) bound to Fe/Mn o
xide; (3) bound to organic matter/sulfides; and (4) acid-soluble residue. S
amples were taken in three seasons and the average concentration of the ele
ments was calculated. Concentrations of elements were mostly well below the
Hungarian standards set for soils and geochemical background values. Most
of the elements were found in the acid-soluble residue and bound to organic
matter/sulfide fractions, characterizing stable compounds in sediments. Th
ere was a difference on the elemental composition of sediments collected at
rivers in the catchment area and harbors with relatively small boat traffi
c. Depending upon the nature of element and local pollution sources the con
centration of Pb and Cu ions was found higher in sediments taken at harbors
than that of small rivers. Generally, it can be stated that elemental conc
entration of sediments inside of the lake is smaller than at the catchment
area, so the pollution from emission sources has not reached the lake yet.
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