The heavy metal availability in long-term polluted soils as affected by EDTA and alfalfa meal treatments

Abstract

A 38-day incubation experiment was carried out in order to evaluate the response of plant-available portions of heavy metals in long-term contaminated arable and grassland soils on addition of ethylenediaminetetraacetic acid (EDTA) and alfalfa (Medicago sativa L.) meal. Soils with different soil management (arable and grassland) from the vicinity of a lead smelter were used in the experiment. Readily available heavy metal fractions of Cd, Pb, Zn and Cu increased in the presence of EDTA at the beginning of experiment. The increase of heavy metal availability was higher in the arable soil with lower content of soil organic carbon than in the grassland soil. Addition of EDTA increased content of K 2 SO 4 -extractable carbon which remained higher throughout the overall time of experiment. During the first part of the experiment, the alfalfa meal addition decreased the available metal concentrations in the EDTA-treated grassland soil whereas no effect of alfalfa meal was observed in EDTA-treated arable soil.

Phytoremediation potential of wild plants growing on soil contaminated with heavy metals

“…It also showed a higher gross calorific value (19,735 kJ kg -1 ) than ragweed (16,469 kJ kg -1 ).The results of this study suggest that mullein has a great potential for phytoextraction and for biomass generation, and that ragweed could be an effective tool of phytostabilisation. KEY WORDS: arsenic; bioconcentration factor; biomass; cadmium; chromium; copper; hyperaccumulator; lead; mullein; nickel; phytoextraction; phytostabilisation; ragweed; rhizosphere; translocation factor; zinc Heavy metals from various sources, including old smelters, could seriously affect the surrounding environment, enter the food chain, and affect human health (1,2). The most severe cases of pollution have been associated with mining, processing, and dumping of heavy metals (3)(4)(5).…”