Effect of Salinity and Sewage Sludge on Heavy Metal Availability And Uptake by Barley Plant

The objective of this study was to evaluate the effect of soil salinity on the availability and uptake of cadmium (Cd)، lead (Pb)، nickel (Ni)، zinc (Zn) and copper (Cu) in a soil treated with municipal sewage sludge (MSS). Soil was salinized (2، 4، 8 and 12 dSm-1 soil paste extract) with NaCl + CaCl2 (1:1ratio)، and incubated at soil field capacity (FC) for 1 month. The soil was treated with a 1. 5 percent of MSS and incubated again at FC for 1 month. Before planting،soluble and DTPA-TEA extractable of heavy metals and soluble Chloride (Cl-) were determined. Then barley seeds were planted and، plants were harvested 10 weeks after germination. The plant indices (dry weight، heavy metal concentration and heavy metal uptake) were measured. The results showed that all salinity levels significantly increased soluble and availability of Cd، Pb، Ni، Zn and Cu. Soil salinity had a significant effect on concentrations and absorption of Cd and Pb in plant (P)