摘要
选取安宁河谷平原矿区周边受Cd和Zn复合污染紫色土为研究对象,采用老化试验,探索添加羟基磷灰石对土壤中重金属生物有效性以及形态分布的影响,羟基磷灰石添加比例(w/w)设置为0%(CK)、1%(P1)、3%(P3)和5%(P5)。结果表明:①添加羟基磷灰石能够显著提高土壤p H值,P1、P3和P5的p H值分别比CK升高了0.13、0.18、0.21个p H单位;②添加羟基磷灰石能够显著降低土壤有效态Cd和Zn (0.025 M HCl提取),相较于CK,P1、P3和P5的有效态Cd含量可分别降低36.0%、78.8%、90.2%,有效态Zn含量可分别降低25.4%、67.4%、84.5%;③添加羟基磷灰石能够明显降低土壤中活性较高的可交换态和碳酸盐结合态Cd和Zn的比例(P<0.05),明显升高了活性较低的铁锰结合态、有机结合态以及残渣态Cd和Zn的比例(P<0.05),从而促进Cd和Zn向非活性态转化。本研究证明了羟基磷灰石在安宁河谷平原土壤重金属污染修复中有较大的应用潜力。
The purple soil contaminated by Cd and zinc surrounding the mining area in An’ning River vally plain was selected as the research object.The effect of nano-hydroxyapatite addition on the bioaccessibility and speciation of Cd and Zn in Purple Soil from Anning valley plain was investigated by aging test.Additive ratios of nano-hydroxyapatite were set as 0%(CK),1%(weight ratio,P1),3%(P3)and 5%(P5).The result showed that:(1)The addition of Nano-hydroxyapatite could significantly increase pH value of soil,the pH values of P1,P3 and P5 were 0.13,0.18 and 0.21 pH units higher than those of CK,respectively.(2)The addition of Nano-hydroxyapatite could significantly reduce the available Cd and Zn in soil(extracted from 0.025 M HCl).Compared with the CK,the available Cd contents of P1,P3 and P5 can be reduced by 36.0%,78.8%and 90.2%,respectively,while the available Zn contents can be reduced by 25.4%,67.4%and 84.5%,respectively;(3)The addition of Nano-hydroxyapatite could significantly reduce the ratio of Cd to Zn in the highly active exchangeable state and carbonate binding state in the soil(P<0.05),and significantly increase the ratio of Cd to Zn in the less active iron-manganese binding state,organic binding state and residue state(P<0.05),thus promoting the conversion of Cd and Zn to the inactive state.These findings indicated that nano-hydroxyapatite could effectively decrease the heavy metals risk in the soil and had good application prospect in the remediation of Cd and Zn contaminated soil in Anning valley plain.
作者
毛志强
杨在文
孙璐
吴扬
施泽明
杨放
MAO Zhi-qiang;YANG Zai-wen;SUN Lu;WU Yang;SHI Ze-ming;YANG Fang(Sichuan Tianshengyuan Environmental Services Co.,Ltd,Chengdu 610072,China;Sichuan Institution of Geological Engineering Investigation Group Co.,Ltd,Chengdu 610072,China;College of Earth Science,Chengdu University of Technology,Chengdu 610059,China)
出处
《四川环境》
2020年第3期1-5,共5页
Sichuan Environment
基金
四川省科技厅计划项目(重点)(18YYJC1029)
四川省国土资源厅科研项目(KJ-2019-3)。
