Numéro |
J. Phys. IV France
Volume 107, May 2003
|
|
---|---|---|
Page(s) | 1103 - 1106 | |
DOI | https://doi.org/10.1051/jp4:20030493 |
J. Phys. IV France 107 (2003) 1103
DOI: 10.1051/jp4:20030493
Heavy metals partioning in three French forest soils by sequential extraction procedure
A. Probst, L. Hernandez and J.L. ProbstLMTG, Université Paul Sabatier, UMR-IRD 5563 du CNRS, 38 rue des 36 Ponts, 31400 Toulouse, France
Abstract
To know the concentration of heavy metal associated to chemical compounds is important to evaluate the environmental risks
on soils, particularly regarding ion bioavailability. The relative mobility and strength of binding of
heavy metals to the soil components can be studied using a sequential extraction procedure which provides a meaningful comparison
between different soil profiles. The heavy metals partitioning has been identified in three different French forest soils:
one cambic podzol, one calcaric cambisol and one mollic andosol, using a new sequential extraction method.
Results show that metal fractionation is metal and site specific. The water leaching phase does not contain any metals.
The proportion of heavy metal leached in the exchangeable and the acid-soluble phase is significant for Cd. The residual phase
is important for Cr, Pb, and to a lesser extend for Ni. The organic matter fraction is dominant for Zn and Cu. Thus, the considered
heavy metals are mainly bounded to iron oxides, to the organic matter and to the mineral residue. The order of heavy metals
availability in the three soils would be:
. Lead isotopes in some extracts of the extraction procedure corroborate the anthropogenic inputs for two soils. These both
infomations allow to trace the
origin, the mobility and the distribution of Pb in the soil.
© EDP Sciences 2003