As part of a larger program aiming at assessing transfer and effects of metals in food webs, this work
studied the spatial distribution of Cd, Cr, Cu, Pb, and Zn in 101 sub-surface soils, systematically sampled
(1 1 km regular grid) over a large area around Annaba, the fourth most-populated city of Algeria. Cd
and Cr exhibited only one abnormally high value, with all other concentrations being close to pedogeological
background. Some places in the centre of the city were polluted by Pb (up to 823 mg kg1),
probably due to aerial deposition from gasoline exhausts. Zn never exceeded regulatory limits over the
whole sampling area. Cu was the only element for which a spatial autocorrelation occurred. A spatial
interpolation by cokriging allowed the identification of agricultural activities as the main Cu pollution
source. Our approach revealed various anthropogenic pollution sources, more efficiently for large-scale
patterns than for local abnormalities.
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