Effects Of Water-soluble Thiourea-formaldehyde Resin For Repairing Cadmium And Copper Contaminated On Microecology In Soil

Cadmium and Copper pollution has become an important soil pollution problem,and various soil amendments have been widely used in immobilization of cadmium and copper.Previous studies have reported that WTF as a novel resin material could reduce the availability of heavy metals,and the heavy metal in the soil can be transformed exchangeable state into stable state.However,the effect of soil microecology responding to the application of WTF is little studied.The aim of this study is to investigate the effects of three soil amendments,WTF resin,hydroxyapatite（HAP）,and Na₂S,on soil heavy metal passivation effect,enzyme activity,and soil microecology under pot experiment.The application of WTF resin can effectively reduce the content of effective cadmium and available copper in soil.After 14 days of WTF resin stabilization treatment of Cd and Cu contaminated soil,the passivation rate of WTF resin to different concentrations of cadmium contaminated soil exceeds 70.57%,the passivation rate of different concentrations of copper contaminated soil exceeded 85.35%.Compared with the control,WTF significantly changed the soil organic matter and increased soil organic matter.Compared with HAP and Na₂S treatments,WTF showed the highest dcreasing effects on the activities of urease.The MBC content in the soil repaired by WTF resin was significantly higher than that of the other two passivators.The soil microbial community structure changed significantly in the soil after WTF resin restoration.These results suggested that these soil microecology with significant changes may be regarded as the biomarkers for the recovery of soil ecological environment,which provides a theoretical basis for the ecological evaluation of WTF.