摘要
海洋沉积物中重金属的活性形态对于指示沉积物污染状况具有重要作用,为探寻简洁且能够有效提取重金属活性形态的浸提方法,实验研究了0.1mol/L和1mol/L盐酸的单级提取和欧共体标准局(European Community Bureau of Reference)提出的BCR分级提取法对胶州湾表层沉积物中重金属(Cr、Cu、Ni、Pb、Zn)和Al、Fe、Mn的浸取效果。结果显示,3种提取方法提取的金属含量呈显著正相关关系,两种浓度的稀盐酸对BCR方法中的酸可提取态和可还原态金属均具有较好浸提效果,但对可氧化态金属浸提能力相对较弱。不同提取方法的人为信号指数(ASI)计算结果表明,BCR浸取法提取结果的金属ASI值最大,表明其对沉积物中金属活性形态提取效率较高;1mol/L HCl提取结果的金属ASI值最低,可能是较高浓度强酸使沉积物较大颗粒内层中"惰性"金属被浸取出来,"增加"了金属活性组分的污染讯息信号;对沉积物中Cu、Pb和Zn而言,0.1mol/L HCl提取结果的ASI值与BCR方法接近。经过Al归一化后,0.1mol/L HCl浸提的重金属含量的空间分布与胶州湾的实际污染状况相吻合,表明0.1mol/L的HCl在一定程度上能够代替复杂的BCR浸取法,此方法可简化重金属活性形态的提取步骤,适合大范围沉积物重金属污染评价。
The speciation of heavy metals in marine sediments plays an important role in indicating the pollution status.To explore a concise and effective method to extract the labile fractions of heavy metals（Cr,Cu,Ni,Pb,Zn）and Al,Fe,Mn,we compared the extraction efficacy of 0.1mol/L HCl,1mol/L HCl and BCR procedure for the metals in surface sediments of the Jiaozhou Bay.The results showed that the contents of extracted metals by these three methods had significant positive correlations with each other.The two HCl methods both had high extraction efficiencies for acid-soluble and reducible forms,but lower extraction efficiencies for oxidizable forms.The metals extracted by the BCR procedure had the highest anthropogenic signal index（ASI）,indicating that the BCR procedure had the highest extraction efficiency for labile fractions of metals among the three methods.The ASI of metals extracted by 1mol/L HCl was the lowest,which may be due to that the non-labile fractions of heavy metals in the inner layer of large particles were leached out by the higher acidity,enhancing the pollution signal of heavy metals in sediments.The ASI of Cu,Pb and Zn extracted by 0.1mol/L HCl was similar to that extracted by the BCR procedure.Furthermore,after the Al normalized,the spatial distribution of labile fraction of heavy metals extracted by 0.1mol/L HCl were consistent with the actual contamination pattern,demonstrating that 0.1mol/L HCl extraction method could replace the complex BCR procedure to a certain extent.This method simplify the extraction procedure for labile fractions of heavy metals and is suitable for the large scale evaluation of heavy metal pollution.
出处
《海洋学报》
CAS
CSCD
北大核心
2016年第10期12-21,共10页
基金
国家973项目课题(2015CB452901)
国家自然科学基金与山东省联合资助项目课题(U1406403)
青岛海洋科学与技术国家实验室"鳌山人才"计划项目(2015ASTP-OS13)
中科院仪器设备功能开发项目(gyh201301)
关键词
重金属
活性组分
浸取方法
沉积物
胶州湾
heavy metals
labile fraction
extraction method
sediment
Jiaozhou Bay
