Because
soil pollutant inhomogeneity could not be overcome by homogenization procedures, common soil
sampling technique combined with ultrasonic extraction with organic solvents can
not mirror the proven dendroremediation effects in a sufficient
manner.
In
contrast to our leaching results, which
refer to the rain water extracts of the whole soil volume, extraction results of
a small percentage of the soil body are not representatively for
the total soil amount.
Despite our substantial quantitative expenditure,
"selective soil sampling" (soil cores) is not suitable for the assessment of the phytoremediation
potential of trees.
Conventional soil sampling can serve only for rough orientation
of the soil contamination degree. Phytoremediation
effects will not be provable in situ by "selected" soil samples, as long as the investigation periods
are restricted to only few years and lateral pollutant
migrations are not excludable.
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