wAbstract
@Urban roadside soils are the grecipientsh of large amounts of
heavy metals from a variety of sources including vehicle emissions,
coal burning waste and other activities. The behavior of heavy
metals in urban roadside soils depends on the occurrence as well
as the total amount. Accordingly, knowledge of the interactions
between heavy metals and other constituents in the soil is required
to judge their environmental impact. In this study, correlations
of heavy metal concentrations (Pb, Zn, Cu, Ag, Se, Ni, Cr and
Ba) to iron extracted using dithionite-citrate-bicarbonate (DCB)
buffer (FeDCB), fulvic acids and particle
size fractions were examined from the Xuzhou urban roadside soils.
Heavy metals except for Cr and fulvic acids had a positive significant
correlation with FeDCB, indicating these
metals and fulvic acids are principally associated with the surfaces
of iron oxides of the soils. Significant positive correlations
were also found between the contents of fulvic acids and heavy
metals, showing these heavy metals (especially for Cu, Ni and
Cr) form stable complexes with fulvic acids. Such finding is of
importance with regard to the increased mobilization of heavy
metals, e.g., into freshwater ecosystems. Ag, Se and Cr are independent
of particle size fractions because of their low concentrations
of Ag and Se in the studied soils. Pb, Zn, Cu, Ba and Ag are mainly
enriched in the finer soil particles (especially ƒ16ƒÊm).
Keywords: Dithionite-citrate-bicarbonate buffer extraction; Iron
oxides; Fulvic acids; Particle size fraction; Urban roadside soils;
Xuzhou; Chinax
Introduction
Materials and methods
@Study area
@Sampling and analysis
Results and discussion
@Relationship between iron and heavy metals
@Relationship between fulvic acids and heavy metals
@Relationship between particle size fractions and heavy metals
Conclusions
References