Supervisors info:
Ευστράτιος Κελεπερτζής, Επίκουρος Καθηγητής, Τμήμα Γεωλογίας και Γεωπεριβάλλοντος, Εθνικό Καποδιστριακό Πανεπιστήμιο Αθηνών
Summary:
In the present study, the source of the contamination of potentially toxic trace
elements in the Greek soils of some areas through the Enrichment Factor (EF)
was investigated. Specifically, using the concentrations of Cu, Pb, Zn, Mn, Ni,
Cr, but also of Fe, Al (that will be used as reference elements in the calculation
of Enrichment Factor), where all of them are gathered from the following 6
Greek cities: Athens, Argos, Volos, Grevena, Thebes, Nemea, we achieved the
calculation of the Enrichment Factor. Our goal was to distinguish the human
and natural sources of trace element contamination in the soils of these cities.
The concentrations of the chemical elements were used from surveys that
have taken place in each area and as a background in the calculation of
Enrichment Factor were placed two different concentration groups, which
means it was calculated with two different methods. In the first case, the
background concentrations of the data that have been calculated in the Earth’s
upper crust were placed and in the second case the median concentration
values of the data that have been calculated by the GEMAS survey in Greek
soils were placed. In the GEMAS study were involved 34 European countries,
from which scientists collected samples from lowland (Gr) and cultivated
soils (Ap) in order to map the geology of the Greek territories. In a general
way, the graphs of the EF following the GEMAS method give safe results for
the urban and rural areas, while the graphs of the EF that have been
calculated based on the composition of the upper continental crust give
incorrect and false results. Also, the charts that use Fe as background
chemical element give safe results in most cases, compared to those that use
Al as background chemical element in the process of both methods (Earth’s
Upper Crust & GEMAS). It turns out that the Enrichment Factor can be used
successfully in soils where geology doesn’t play a major role in regulating the
concentrations of chemical elements, but only human activities (urbanization,
industries, crops) have a significant influence. However, in soils where
geology has a significant presence, especially when ultramafic rocks are
present, the values of EF for Cr, Mn, Ni are in many cases higher than the
value of 2, which is the limit for distinguishing natural (<2) from human
factors (>2), so we think that the source of potentially toxic trace elements is
due to the human factor, while it is almost purely due to the geological factor,
because of the rocks that occur in each area.
Keywords:
Enrichment factor, potentially toxic trace elements, environmental contamination, urban and agricultural soils, ultramafic rocks.
