铅稳定同位素在土壤污染物源解析中的应用

[Application of Pb stable isotope in source identification of soil pollutants].

作者信息

Wu Long-hua, Zhang Chang-bo, Zhang Hai-bo, Luo Yong-ming

机构信息

State Key Laboratory of Soil and Sustainable Agriculture, Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.

出版信息

Huan Jing Ke Xue. 2009 Jan;30(1):227-30.

PMID:19353885

Abstract

Stable isotopes are key importance for tracing the source of heavy metals in soils. 11 surface soil samples were collected in a contaminated site according to geostatistical results, which had a series of concentrations from almost background value of Pb to more than 2 000 microg x g(-1). Pb stable isotope composition of the soil samples was analyzed to imply the sources. The results showed that 206Pb/207Pb, 208Pb/204Pb and 206Pb/204Pb of soil samples were all remarkably correlated linearly with reciprocals of Pb concentration, and 206Pb/204Pb had a significant positive linear correlation with 208Pb/204Pb, which was consistent with binary mixing model. It can be inferred that soil Pb mainly came from two sources, an anthropogenic source and soil parent material.

摘要

稳定同位素对于追踪土壤中重金属的来源至关重要。根据地质统计学结果，在一个污染场地采集了11个表层土壤样本，这些样本中铅的浓度范围从几乎背景值到超过2000微克×克⁻¹。分析了土壤样本的铅稳定同位素组成以推断其来源。结果表明，土壤样本的²⁰⁶Pb/²⁰⁷Pb、²⁰⁸Pb/²⁰⁴Pb和²⁰⁶Pb/²⁰⁴Pb均与铅浓度的倒数呈显著线性相关，且²⁰⁶Pb/²⁰⁴Pb与²⁰⁸Pb/²⁰⁴Pb呈显著正线性相关，这与二元混合模型一致。可以推断，土壤中的铅主要来自两个来源：一个是人为来源，另一个是土壤母质。