The role of Fe- and Mn-oxides during EDTA-enhanced phytoextraction of heavy metals
M. Komárek, P. Tlustoš, J. Száková, V. Chrastný, J. Balíkhttps://doi.org/10.17221/2203-PSECitation:Komárek M., Tlustoš P., Száková J., Chrastný V., Balík J. (2007): The role of Fe- and Mn-oxides during EDTA-enhanced phytoextraction of heavy metals. Plant Soil Environ., 53: 216-224.
In several cases ethylenediaminetetraacetic acid (EDTA) proved to be an efficient mobilising amendment during chemically enhanced phytoextraction of heavy metals. The presence of Fe-(hydr)oxides and their dissolution after the addition of EDTA can limit the phytoextraction of the targeted heavy metals due to the high stability of the formed Fe(III)EDTA complexes. This study has focused on the influence of Fe- and Mn-oxides and hydroxides dissolution on heavy metal uptake by Zea mays in a two-year EDTA-enhanced phytoextraction process. Incubation experiments and speciation modelling proved the increased concentrations of Mn and Fe through the dissolution of Mn-and Fe-(hydr)oxides. Furthermore, increased Fe and Mn accumulation was observed in maize plants after the second year of the phytoextraction process. Therefore, the presence of Mn- and especially Fe-(hydr)oxides proved to be a limiting factor during EDTA-enhanced phytoextraction of heavy metals from contaminated soils.Keywords:EDTA; phytoextraction; Fe oxides; Mn oxides; heavy metals; Zea mays