磷酸二氢钾和羟基磷灰石对灌淤土壤中重金属的迁移影响

Effect of Potassium Dihydrogen Phosphate and Hydroxyapatite on the Transport of Heavy Metals in Silted Soil

通过模拟灌淤土壤重金属污染,以大蒜盆栽实验对比分析磷酸二氢钾和羟基磷灰石对土壤中重金属Pb、Ni、Cr的迁移影响.结果表明:添加0.8 g·kg^(-1)磷酸二氢钾和羟基磷灰石分别使土壤pH下降14.32%和增加5.31%.磷酸二氢钾和羟基磷灰石均显著提高了土壤中速效磷含量,降低了土壤中Pb、Ni、Cr交换态含量,且羟基磷灰石降低重金属交换态效果比磷酸二氢钾略好.磷酸二氢钾和羟基磷灰石明显降低了大蒜地上、地下部分重金属Pb、Ni、Cr的含量.与对照相比,磷酸二氢钾和羟基磷灰石分别使大蒜地上、地下部分Pb、Ni、Cr最多降低了22.93%、33.49%、26.73%、32.06%、25.88%、33.11%和31.35%、56.74%、30.45%、40.82%、35.59%、61.86%,磷酸二氢钾和羟基磷灰石能有效地稳定土壤中Pb、Ni、Cr,且羟基磷灰石稳定效果比磷酸二氢钾略好.

The pot experiment of the garlic was used to simulate heavy metal pollution in the silting soil,and the effects of potassium dihydrogen phosphate and hydroxyapatite on the migration of heavy metals Pb,Ni and Cr in the soil were compared and analyzed.The results showed that:the soil pH decreased by 14.32%and increased by 5.31%,respectively,adding 0.8 g·kg^(-1) potassium dihydrogen phosphate and hydroxyapatite.Both potassium dihydrogen phosphate and hydroxyapatite significantly increased the content of available phosphorus in the soil,and reduced the content of the exchangable state for Pb,Ni and Cr in the soil,where the reduction effect of the exchange state for hydroxyapatite was slightly better than that of potassium dihydrogen phosphate.The content of heavy metals Pb,Ni,Cr in garlics aboveground and underground were significantly reduced by potassium dihydrogen phosphate and hydroxyapatite.Potassium dihydrogen phosphate and hydroxyapatite make the content of Pb,Ni and Cr reduced by 22.93%,33.49%,26.73%,32.06%,25.88%,33.11%and 31.35%,56.74%,30.45%,40.82%,35.59%,61.86%,respectively in the aboveground and underground parts of garlics.Both potassium dihydrogen phosphate and hydroxyapatite can effectively enhance the stability of soil Pb,Ni,Cr,and hydroxyapatites stable effect is slightly better than that of potassium dihydrogen phosphate.