1. Introduction
The distribution of heavy metals in soil fractions, so-called chemical
fractionation, is an important aspect of soil geochemistry as it governs
the behaviour of these elements in soil and plays a relevant rule in determining
their availability for soil biota. Availability is considered an essential
parameter for effective uptake and accumulation of heavymetals
in soil organisms, and therefore an important tool in assessment of environmental
risk. A number of physicochemical and biological processes
influence the bioavailability of heavy metals in soil, indicating that
their transfer from soil to biota is as a very complex phenomenon.