PAM与粉煤灰改良沙土中重金属的迁移和富集规律

Metal Transportation and Accumulation in Sandy Soil Amended by Fly Ash and PAM

探讨复合施用聚丙烯酰胺(PAM)和粉煤灰改良沙土时,重金属(以Cr、As、Ni为例)在土壤、植物当中的运移规律,以及PAM在粉煤灰改良土壤中对重金属运移规律的影响。采取田间小区试验的方法,设计3种PAM施用量(0、60和120 mg/kg)和4种粉煤灰施用量(0、5%、10%和15%),其中不添加PAM和粉煤灰的处理为对照。试验结果表明:添加粉煤灰后,表层沙土当中Cr、Ni元素含量增加,而粉煤灰施用量为15%时As元素含量减少。在粉煤灰改良土壤中添加PAM能够将更多重金属固定在土壤表层,从而抑制重金属的淋洗,同时减少玉米对Cr、As、Ni的吸收。

Polyacrylamide （PAM） was added to fly ash to amend sandy soil. The migration of heavy metals, such as Cr, As and Ni in soil-plant system and the influence of PAM on it were investigated, respectively. The experimental design included three PAM application rates （0, 60 mg/kg and 120 mg/kg） and four fly ash application rates （0, 5% , 10% and 15% ）. The treatment without fly ash and PAM was prepared as a control. The results showed that the addition of fly ash increased the concentrations of Cr and Ni in the surface sandy soil, while there was a decline in As concentration at high fly ash application rates （ 15% ）. The addition of PAM could stabilize a large quantity of heavy metals within topsoil to control their leaching risk as well as reduce the amounts of Cr, As and Ni absorbed by corn.