【摘要】 [目的]探讨氮磷肥施用对保水剂钝化土壤重金属铅镉效果的影响,为揭示土壤水肥保持和重金属污染治理的协调性机制,制定SAP应用技术规程等提供参考。[方法]采用土柱淋溶试验方法,比较添加氮肥和磷肥对SAP钝化土壤铅(Pb)、镉(Cd)效果的影响。[结果]在Pb,Cd复合污染土壤中SAP用量为1.0g/kg时,控氮释磷效果较好,相比无SAP的对照处理,Pb累积淋失量减少5.1%,Cd累积淋失量增加13.6%;氮磷肥添加试验表明,添加氮肥的SAP处理Pb累积淋失量增加76.7%,Cd累积淋失量增加47.6%,添加磷肥的SAP处理Pb累积淋失量减少26.0%,Cd累积淋失量减少20.5%;添加复合氮、磷肥的SAP处理Pb累积淋失量减少2.3%,Cd累积淋失量增加8.3%。[结论]保水剂具有控氮释磷效应,且对土壤中的Pb,Cd有一定钝化作用;氮肥降低SAP钝化Pb,Cd的效果,而磷肥增强SAP钝化Pb,Cd的效果;氮、磷肥复合对SAP钝化Pb的效果影响不显著,但会降低SAP钝化Cd的效果。更多还原

【Abstract】 [Objective] The effects of the adoption of nitrogen and phosphorus fertilizer on the passivation effectiveness of super absorbent polymer(SAP) on heavy metal Pb and Cd in soil are studied in order to reveal the coordination mechanism of moisture and fertilizer conservation and heavy metal pollution control, and provide reference for SAP application rules. [Methods] We adopted the soil column leaching method, testing the impact of nitrogen and phosphorus fertilizer on SAP’s passivation effectiveness on Pb and Cd in the contaminated soil. [Results] When SAP dosage was 1.0 g/kg in lead and cadmium contaminated soil, the effect of nitrogen conservation and phosphorus activation synergism was better. Pb accumulative leaching loss amount was reduced by 5.1% compared with comparison group without SAP, and Cd was 13.6% higher than the contrasting group. In the comparison experiment of adding nitrogen and phosphorus fertilizer in the soil, it showed that the accumulative leaching loss of Pb was increased by 76.7% when soil with SAP treatment was added with nitrogen fertilizer, the cumulative leaching loss of Cd increased by 47.6%, and the cumulative leaching loss of Pb was reduced by 26% when adding with phosphate fertilizer, and the cumulative leaching loss of Cd decreased by 20.5%; Besides, the cumulative leaching loss amount of Pb decreased by 2.3% when adding nitrogen and phosphate fertilizer compound in the soil treated with SAP, and that of Cd increased by 8.3%. [Conclusion] SAP has the effect of conserving nitrogen and activating phosphorus, and has passivation effect on Pb and Cd in soil; nitrogen fertilizer inhibites SAP’s passivation effect on Pb and Cd, and phosphate fertilizer promotes the work. Nitrogen and phosphate fertilizer compound on SAP’s passivation impacts on Pb was not significant, and it inhibited the SAP’s work on Cd.更多还原