Abstract:
Effects of different pollution sources,simulated with different carriers of heavy metals such as contaminated soil,mine tailings,and sewage sludge,on growth of rice and transfer of nutrients and heavy metals in the soil paddy rice(Oryza sativa L.) system were studied with pot experiment in greenhouse. Results showed that effects on plant growth varied with sources and were in the order of contaminated soil>mine tailings>sewage sludge>tailing+sewage sludge. The concentrations of Cu,Zn,Pb and Cd were higher in the plants growing in soil treated with contaminated soil due to higher extractability and toxicity of the heavy metals therein. Rice growing in the soil applied with sewage sludge and tailing+sludge had lower concentrations of Zn,Pb and Cd because of lower extractability and bioavailability of the heavy metals,which might get complexed with organic matter in the sewage sludge. Meanwhile plant growth was also related to nutrient uptake of the plants. It was also demonstrated that by adding chemical agents into soil to determine heavy metal loading capacity of the soil was feasible and safe,for under lab conditions response of the test plants would be the most apparent.