Chelators effect on soil Cu extractability and uptake by Elsholtzia splendens.
Phytoremediation is emerging as a potential cost-effective solution for remediation of contaminated soils, and bioavailability of metal in the soil for plant uptake is an important factor for successful phytoremediation. This study aimed at investigating the ability of EDTA and citric acid for enhancing soil bioavailability of Cu and phytoremediation by Elsholtzia splendens in two types of soils contaminated with heavy metals [i.e. mined soil from copper mining area (MS), and paddy soil (PS) polluted by copper refining]. The results showed that addition of 2.5 mmol/kg EDTA significantly increased the H(2)O extractable Cu concentration from 1.20 to 15.78 mg/kg in MS and from 0.26 to 15.72 mg/kg in PS, and that shoot Cu concentration increased 4-fold and 8-fold as compared to the control. There was no significant difference between the treatment with 5.0 mmol/kg EDTA and that with 2.5 mmol/kg EDTA, probably because that 2.5 mmol/kg EDTA was enough for elevating Cu bioavailability to the maximum level. As compared with the control, citric acid had no marked effect on both soil extractable Cu and shoot Cu concentration or accumulation. The results indicated that EDTA addition can increase the potential and efficiency of Cu phytoextraction by E. splendens in polluted soils.
College of Natural Resources and Environmental Science, Zhejiang University, Hangzhou 310029, China. jiangly111311@sina.com
Li-ying
LY
Jiang
Xiao-e
XE
Yang
D001673:Biodegradation, Environmental; D001693:Biological Transport, Active; D002614:Chelating Agents; D019343:Citric Acid; D003300:Copper / Q000302:isolation & purification / Q000378:metabolism*; D004492:Edetic Acid; D019686:Lamiaceae / Q000254:growth & development / Q000378:metabolism*; D012989:Soil Pollutants / Q000302:isolation & purification / Q000378:metabolism*; D014867:Water
D002614:Chelating Agents; D012989:Soil Pollutants; D014867:Water; D019343:Citric Acid; D003300:Copper; D004492:Edetic Acid