5种调理剂对水田土壤中镉赋存形态的影响及其钝化效果评价  

Effects of Five Conditioners on Speciation of Cadmium in Paddy Soil and Evaluation of Their Passivation Efficacy

作　　者：刘辽源 LIU Liaoyuan(Hua’an County Bureau of Agriculture and Rural Affairs,Zhangzhou,Fujian 363800)

机构地区：[1]华安县农业农村局,福建漳州363800

出　　处：《中国农学通报》2024年第24期79-86,共8页Chinese Agricultural Science Bulletin

基　　金：2021年福建省生态农业专项资金项目“华安县受污染耕地重金属联合阻控技术研究及示范区建设”(闽财农指〔2020〕105号)。

摘　　要：本研究旨在评估5种不同调理剂——石灰(SCⅠ)、白云石粉(SCⅡ)、牡蛎壳粉(SCⅢ)、泥炭土(SCⅣ)和硅钙镁钾肥(SCⅤ)对水田土壤中镉(Cd)污染的钝化修复效果。采用受Cd污染的弱酸性水田土壤为材料,通过盆栽模拟试验,分析了这5种调理剂对土壤pH、土壤中Cd赋存形态分布特征及生物有效性的影响。试验结果显示,供试土壤分别添加SCⅠ、SCⅡ、SCⅢ、SCⅣ、SCⅤ0.6 g/盆(2.0 kg土壤)处理60 d后,土壤pH分别提高了1.81、1.49、1.17、0.48、0.60个单位;土壤中水溶态、弱酸提取态、可还原态、可氧化态、残渣态Cd分布特征发生了不同程度的变化。具体而言,水溶态Cd分布系数分别下降了0.70%、0.54%、0.63%、0.21%和0.24%,弱酸提取态Cd分布系数分别下降了17.68%、8.39%、11.52%、18.13%和15.95%,而残渣态Cd分布系数分别上升了14.27%、5.33%、11.54%、17.70%和14.34%(P<0.05)。这些变化表明,5种调理剂均能有效降低土壤中有效态Cd含量,并增加不可利用态Cd含量(P<0.05)。SCⅠ、SCⅡ、SCⅢ、SCⅣ和SCⅤ对土壤中Cd污染的钝化效果分别为38.98%、18.42%、25.33%、39.98%和35.12%。因此,这5种调理剂钝化修复酸性水田土壤中Cd污染均显示出良好的潜力,为安全利用受Cd污染的酸性水田提供了新的技术方案,并值得进一步的田间验证和示范应用。To assess the efficacy of five conditioning agents of lime powder(SCⅠ),dolomite powder(SCⅡ),oyster shell powder(SCⅢ),peat soil(SCⅣ)and silicate-calcium-magnesium-potassium fertilizer(SCⅤ)on passivation repair cadmium(Cd)pollution in paddy soils,this study conducted pot experiments using slightly acidic paddy soil with Cd pollution,and the effects of these conditioners on soil pH,the distribution characteristics of Cd speciation in the soil,and its bioavailability were monitored and analyzed.The results showed that after 60 days of each treatment,the soil pH increased by 1.81,1.49,1.17,0.48 and 0.60 units,respectively.The distribution characteristics of water-soluble fraction,mild acido-soluble fraction,reducible fraction,oxidizable fraction and residue fraction Cd in the soil had changed in different degrees.Specifically,the distribution coefficient of water-soluble fraction Cd was reduced by 0.70%,0.54%,0.63%,0.21%,and 0.24%,respectively;mild acido-soluble fraction Cd was reduced by 17.68%,8.39%,11.52%,18.13%,and 15.95%;and the distribution coefficient of residual fraction Cd was increased by 14.27%,5.33%,11.54%,17.70%,and 14.34%(P<0.05).This indicated that SCⅠ,SCⅡ,SCⅢ,SCⅣand SCⅤreduced the bioavailable Cd and increased the non-bioavailable Cd in the soil to varying degrees(P<0.05),and the passivation effects were 38.98%,18.42%,25.33%,39.98%and 35.12%for Cd pollution in soils respectively.Therefore,all five conditioners demonstrated certain effectiveness in passivation repair Cd pollution in acidic paddy soils,warranting further test and verification demonstration application in safe utilization production technologies of Cd polluted acid paddy fields.

关 键 词：土壤调理剂 水田土壤 镉 生物有效性 钝化效果 镉污染 土壤修复 

分 类 号：S511.062[农业科学—作物学]