With the development of industry, agriculture, mining and transport, the
anthropogenic impact on the environment has increased. Thus, urban sediments or
road sediments can be found within cities. They represent an important source of
information for various potential pollutions within the urban environment. In my
master's thesis, I focused on the content of PTE in road sediments in the city of Ptuj
in the northeastern part of Slovenia. The nine most suitable locations were selected.
Samples in the grain size range from 250 μm to 125 μm, from 125 μm to 63 μm and
< 63 μm were used for the analyses. I selected three samples for detailed
mineralogical analysis of clay minerals. XRD results showed that the mineral
composition of all locations is very similar (all locations have a high proportion of
dolomite and quartz, this is followed by plagiclase, muscovite and calcite). The latter
differ slightly only in the proportion of minerals present. The results of mineralogical
and geochemical analyzes confirm the geological background of the researched
area, and I compared the obtained data with the values of the natural geological
background of the Slovenian Pannonian Basin. I divided the elemental composition
data of the samples into four groups: major elements, potentially toxic elements
(PTE), rare earth elements (REE) and platinum group elements (PGE). The
contents of the main elements, except for Ca, Na and Mg, range within the
expected values of the natural geological background. Elements with problematic
contents are: Ag, Bi, Cr, Cu, Mo, Ni, Sb and Zn. All the listed elements occur within
one or more locations with contents that are much above the expected natural
values. The calculated enrichment factor shows us the enrichment of road sediment
with Bi, Cr, Mo, Cu, Sb and Zn. SEM/EDS results showed that road sediment
samples (mineral and elemental composition) are very similar to each other. Based
on the results we obtained, I conclude that the city of Ptuj is anthropogenically
polluted, mostly by traffic.
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