Fe-Al改性硅藻土与CaO配施改良Cd污染土壤

Improvement of Cd-contaminated soil by Fe-Al modified diatomite combined with CaO

以人工模拟Cd污染土壤为研究对象,以Fe-Al改性硅藻土和CaO为原料制备组配改良剂,通过土壤培养试验研究了Fe-Al改性硅藻土与CaO不同配比对组配改良剂改良Cd污染土壤效果的影响.结果表明,向Cd污染土壤施加Fe-Al改性硅藻土与CaO以不同配比所制得组配改良剂对土壤Cd形态、pH值、CEC值、OM值、含水率、有效氮、速效磷、有效钾均产生了积极的影响.当Fe-Al改性硅藻土与CaO的配比为1:6时,土壤可交换态Cd含量较空白对照降低了74.67%,较单一施加Fe-Al改性硅藻土和CaO分别降低了64.63%和7.87%,与对照相比,土壤pH值提升了0.45,土壤CEC提升了69.78%,土壤有效氮、速效磷分别提升了28.57%、70.85%.Fe-Al改性硅藻土与CaO配施能有效控制土壤Cd污染,同时还可有效改善土壤耕作性能.

The artificially simulated Cd contaminated soil was used as the research object.The Fe-Al modified diatomite and CaO were used as raw materials to prepare the modifier.The soil-culture experiment was used to study the effect of Cd-contaminated soil was improved by adding the different ratios of Fe-Al modified diatomite and CaO.The results showed that by applying Fe-Al modified diatomite and CaO to Cd contaminated soil with different ratios,the Cd forms,pH value,CEC value,OM value,water content,available nitrogen,available phosphorus and available potassium all have positive effects.When the ratio of Fe-Al modified diatomite to CaO is 1:6,the soil exchangeable Cd content was reduced by 74.67%compared with the blank control,and compared with single application of Fe-Al modified diatomite and CaO,which decreased by 64.63%and 7.87%,respectively.The soil pH value increased by 0.45,the soil CEC increased by 69.78%and the available nitrogen and phosphorus increased by 28.57%and 70.85%respectively compared with the blank control.Fe-Al modified diatomite combined with CaO can effectively control soil Cd pollution and improve soil tillage performance.