黄棕壤镉污染的电动修复及肥力的提升

Effect of electrokinetic remediation on fertility of soil contaminated by cadmium

近些年来,有关施加电场以去除土壤中污染物的报道较多,但是关于电动力学对土壤肥力的影响方面的报道很少。文章研究了电动力学(1V·cm-1)对土壤肥力的影响。修复前后测量的指标有土壤有机质(SOM)、pH、电导率(EC)、氧化还原电位(ORP)、有效氮、速效磷、速效钾。镉质量分数约为100mg·kg-1的模拟污染土壤经电动力学处理60h后,镉的平均去除效率为71%。土壤中的有效氮、速效磷和速效钾分别平均增加38.49%、47.55%和26.81%,同时TOC也增加了7.96%。总之,电动力学修复后,土壤的肥力有了明显的提升。研究结果表明,电动力学在有效去除土壤中镉的同时还能提升土壤的肥力,是一种可行的土壤修复技术。

In recent years, the application of electric field for the remediation of polluted soil has been increasingly concerned. However, little is known about the impact of this method on soil fertility. The effects of electrokinetics （1 V.cm^-1） on soil fertility were investigated in this study. The synthetic polluted sample was made by spiking 100 mg.kg^-1 of cadmium （Cd） to the soil. Soil organic matter （SOM）, pH, electrical conductivity （EC）, Oxidation Reduction Potential （ ORP ） , available nitrogen （ N ） , available phosphorus （P） and available potassium （K） were monitored before and after electric remediation. After 60 hours of electrokinetic treatment, the values ofpH and EC were increased gradually from the anode to the cathode. However, the values of ORP were slowly decreased. The average removal rate of Cd was about 71%. Meanwhile, the values of available N, P and K in soil were increased by 38.49%, 47.55% and 26.81% in average, respectively. TOC was also increased by 7.96%. The additional advantage of electrokinetic remediation has been achieved in terms of the enhancement of soil fertility. The results obtained in this study demonstrated that electrokinetic method is quite applicable for polluted soil remediation.