Abstract:
Soil is an important natural resource for human survival and development. However, the threat of soil heavy metal contamination in China is becoming increasingly serious. Six remediation agents for soil heavy metal contamination in this study, including phosphorus-containing material, calcium carbonate, biochar, shell powder and natural sulfhydryl minerals, were added to paddy soil contaminated with cadmium (Cd) at varied rates in a pot experiment to investigate their effects on soil properties, bio-availability of Cd and Cd content in crops. Three evaluation factors were selected by the method of principal component analysis (PCA), and ranked based on the comprehensive scores after determining their weights. The results showed that the six remediation agents significantly reduced the bio-availability of Cd in paddy soil and the content of Cd in rice. Thecalcium carbonate had the best remediation effects on the heavy metal contaminated soil, following by the biochar and the phosphorous-containing material, while the natural sulfhydryl mineral was presented the worst remediation effect.