Abstract:
In order to clarify the feasibility of chelate-induced-leaf beet (
Beta vulgaris var. cicla L., a hyperaccumulator for Cd) to the remediation of cadmium (Cd) and lead (Pb) contaminated soil, different concentrations of EDTA and citric acid (0, 2.5, 5, 7.5, 10 mmol kg
−1) were added to soil collected from farmland of Anxin, Xiong'an New District in a pot experiment. The results showed that: (1) Compared with the control, the addition of EDTA chelating agent inhibited plant growth and biomass, while the citric acid treatment at a certain concentration significantly promoted plant growth. The addition of 5 mmol kg
−1 citric acid increased plant height, stem diameter and biomass by 4.52%, 44.07% and 50% (2) The concentrations of available Cd and Pb in soil were increased by 108.61%-235.39% and 67.98%-224.16% after the addition of EDTA chelating agent, and by 180.07% and 186.01% after the addition of citric acid, respectively. The activation efficiency of EDTA on soil heavy metals was significantly higher than that of citric acid. (3) EDTA promoted the absorption of Pb, while citric acid with a certain concentration promoted the absorption of Cd by
Beta vulgaris var. cicla L. (4) Ammonium nitrogen, available phosphorus and available potassium were increased significantly after treatment with chelating agent, which showed that soil fertility was not negatively affected. Our study indicated that chelate-induced-
Beta vulgris var. cicla L. was practical in the remediation of Pb-Cd contaminated soil.