In situ stabilization of metals (Cu, Cd, and Zn) in contaminated soils in the region of Bolnisi, Georgia

摘要: The topsoils of the Mashavera valley in SE Georgia are highly contaminated with Cu, Zn and Cd from mining activities upper reaches River. Previous laboratory experiments have shown that an situ immobilization these metals (M) by Fe-oxides would be adequate remediation technique for study area. A field experiment was thus initiated 2008 order to assess such a treatment under natural conditions. To verify results pot conducted growth chamber. Two experimental fields differing degrees M contamination were chosen close town Bolnisi, Georgia, divided into 8 (Field I, weakly contaminated) 16 II, heavily plots. Half plots at each remediation. 1% (w/w) zerovalent iron grit applied homogeneously mixed (to depth 0–20 cm) Composite samples all taken directly after March, June October again March 2009. Spinacia oleracea L. cultivated Mobile fractions topsoil, concentration L., contents amorphous Fe-oxides, changes soil pH plant available inorganic P then determined In topsoil Field II grit, incubated 4 weeks subsequently weeks. soil, also determined. mobile fraction Cu decreased significantly 48% 2009 treated soils I. control soils, 52%. 20% 51%, respectively, while no significant found. These confirmed data experiment. decrease concentrations is due formation application fixation innerspheric complexes. Nevertheless, uptake not affected Fe experiment, increased treatment. addition, No influence on detected. treatments, soil-P availability reduced as well This could traced back P-fixation freshly-formed Fe-oxides. levels still sufficiently high according German regulations. suitable only limited extent efficiency reduce sequence > Zn. higher if had portion total content. Soil marginally but Cd, most important criteria, reduced.