在白银市白银区大田条件下，以苦荞麦为指示作物，以凹凸棒石粉和纳米超微功能材料为试材，研究了凹凸棒石粉复配纳米超微功能材料对土壤重金属钝化效果。结果表明，试验农田空白土壤中，Pb和Cd含量分别为300.7 mg/kg 、24.36 mg/kg；施加凹凸棒石粉3 000 kg/hm2复配纳米超微功能材料3 000 kg/hm2时，土壤中重金属的有效态降低幅度最大，对重金属的钝化效果明显，Pb的降低率达到了50.0%。施加凹凸棒石粉复配纳米超微功能材料或单独施加凹凸棒石粉后，荞麦中重金属的吸收量均明显少于对照不添加任何材料，且凹凸棒石粉复配纳米超微功能材料对重金属的钝化效果明显优于单独施加凹凸棒石粉。

With tartary buckwheat as the indicator crop and attapulgite powder and nanometer ultramicro functional materials as the test materials， the passivation effect of attapulgite powder combined with nanometer and ultrafine functional materials on soil heavy metals was studied in baiyin district of Baiyin City. The results showed that the contents of Pb and Cd in the blank soil of the test farmland were 300.7 mg/kg and 24.36 mg/kg respectively；when attapulgite 3 000 kg/hm2， composite nano ultra functional material 3 000 kg/hm2 was applied， the effective state of heavy metals in the soil decreased the most， the passivation effect on heavy metals was obvious， and the reduction rate of Pb reached 50.0%. After applying attapulgite combined with nanometer and ultramicro functional materials or applying attapulgite alone， the absorption of heavy metals in buckwheat was significantly lower than that of the control without adding any materials， and the passivation effect of attapulgite combined with nanometer and ultramicro functional materials was obviously better than that of attapulgite applied alone and the control.

S156

2019年中央土壤污染防治专项资金投资计划项目“农用地土壤污染治理与修复试点项目”。