Heavy metal displacement in salt-water-irrigated soil during phytoremediation.
In regions where phytoremediation is carried out, brackish water must often be used. However, no information exists concerning the consequences of saline-water irrigation on the mobility of heavy metals in sludge applied to soil during phytoremediation. The purpose of this experiment was to determine the effect of NaCl irrigation on displacement of seven heavy metals in sludge (Cd, Cu, Fe, Mn, Ni, Pb, Zn) applied to the surface of soil columns containing barley plants. Half the columns received NaCl irrigation (10,000 mg L(-1)) and half the columns received tap-water irrigation. Half the columns were treated with the chelating agent EDTA. With no EDTA, irrigation with the NaCl solution increased the concentrations of Cd, Fe, Mn, and Pb in the drainage water above drinking-water standards. Irrigation of sludge farms with brackish water is not recommended, because saline water increased the mobility of the heavy metals and they polluted the drainage water.
Wahla
Intkhab Hazoor
IH
Department of Agronomy, 2004 Throckmorton Plant Sciences Center, Kansas State University, Manhattan, Kansas 66506-5501, USA.
Kirkham
M B
MB
D001673:Biodegradation, Environmental; D002614:Chelating Agents / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004784:Environmental Monitoring / Q000379:methods; D019216:Metals, Heavy / Q000032:analysis* / Q000633:toxicity; D063245:Plant Development; D012722:Sewage / Q000737:chemistry*; D012965:Sodium Chloride / Q000494:pharmacology*; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity; D013995:Time; D014872:Water Movements
D002614:Chelating Agents; D019216:Metals, Heavy; D012722:Sewage; D012987:Soil; D012989:Soil Pollutants; D012965:Sodium Chloride; D004492:Edetic Acid