摘要
通过室内土壤培养实验,研究添加沸石、磷矿粉和石灰3种改良剂对污染土壤Pb、Zn化学形态和生物可给性的影响.结果表明,土壤Pb主要以Fe-Mn氧化物结合态为主,而Zn主要以残渣态为主.改良剂对土壤Pb、Zn化学形态的影响随着培养时间的不同而不同.培养1个月时,2%磷矿粉和2%石灰处理可分别导致土壤醋酸(HOAC)提取态Pb含量下降76.0%和25.6%,3种改良剂处理导致土壤HOAC提取态Zn含量比对照处理降低6.1%～17.0%.培养2个月时,磷矿粉和石灰处理分别导致土壤HOAC提取态Pb含量下降62.8%和39.0%,石灰处理导致土壤HOAC提取态Zn含量下降34.6%.3种改良剂对土壤Pb、Zn的生物可给性也有影响,也随着土壤重金属种类和培养时间的不同而异.培养1个月时,沸石和磷矿粉可分别导致土壤Zn的生物可给性降低15.9%和14.9%,但培养2个月后3种改良剂对Zn的生物可给性却没有影响.研究结果表明,在酸性Pb、Zn复合污染农田土壤中均可以选择这3种改良剂来进行土壤改良,减少重金属的污染风险.
Effects of zeolite, phosphate rock and limestone on the fractionation and bio-accessibility of lead （Pb） and zinc （Zn） in soil were studied by using soil culture experiment. The results showed that the fractionations of Pb mainly exist in Fe-Mn oxidation, and Zn exist in residual fractionation. The effect of amendments on the fractionation of Pb and Zn in soil differed with soil incubation time. After one month incubation, the treatment of adding 2% （W/W） phosphate rock and limestone lowered the concentration of HOAC-soluble Pb by 76.0% and 25.6% respectively, comparing with the control. Addition of zeolite, phosphate rock and limestone reduced HOAC-soluble Zn within soil from 6.1% to 17.0% in one month incubation. After two month incubation, the treatment of adding phosphate rock and limestone lowered HOAC-soluble Pb by 62.8% and 39.0% in soil, and a 34.6% reduction of HOAC-soluble Zn was found in limestone treatment. Though these three amendments all affected the bio-accessibility of Pb and Zn in soil, the effect differed with the type of heavy metals and incubation time. The bio-accessibility of Zn in zeolite and phosphate rock treatments decreased by 15.9% and 14.9% after one month incubation, but these three amendments showed less effects on the bio-accessibility of Zn after two month incubation. This study suggests that zeolite, phosphate rock and limestone can be used to remediate Pb- and Zn-contaminated soils.
出处
《环境化学》
CAS
CSCD
北大核心
2013年第9期1693-1699,共7页
Environmental Chemistry
基金
国家重金属污染治理专项"广西环江县大环江流域土壤重金属污染治理工程项目"
中国科学院院地合作项目"江西省典型矿区及周边土壤重金属污染特征及其联合修复技术研发"
国家水体污染控制与治理科技重大专项(2009ZX07212-001-05)资助
关键词
土壤
改良剂
铅
锌
化学形态
生物可给性
soil, amendments, lead, zinc, fractionation, bio-accessibility.
