The effects of chemical and organic manures on stabilization of Lead and Cadmium in polluted soils

The application of phosphate fertilizers and organic matter have been known as a stabilization (immobilization) technique to reduce solubility of heavy metals in contaminated soils. In this respect، the application of phosphate fertilizers and municipal solid waste compost on mobility of Pb and Cd and uptake of those metals studied by plant in a polluted loamy soil. The green house study was performed in complete randomized design with treatments of ammonium phosphate (75mg P2O5/kg)، triple superphosphate (75mg P2O5/kg) and municipal solid waste compost (2%) compared with control in three replicates. The results showed that the availability of lead was significantly reduced with increased phosphate fertilizers in comparison with control. The applied various P fertilizers decreased uptake of Cd and Pb significantly whereas compost did not affect significantly by aerial part of Gladiola. Also the applied P fertilizers decreased soluble and exchangeable Cd and Pb fractions، compared with control، but compost had not affected. It is therefore concluded that the application of P fertilizers within agricultural fields may be prevented entering heavy metals into the food chain.