长沙市乔口镇土壤重金属地球化学基线值的厘定及应用

Geochemical baseline of heavy metals in the soils of Qiaokou town,Changsha city and its application

随着工业化和城市化等人类活动影响的加强,土壤表层重金属含量趋于上升.作为区分自然背景和人为影响的指标,土壤重金属地球化学基线为土壤的污染评价提供了重要的参考依据.本研究以湖南省长沙市乔口镇为研究区域,利用标准化方法和累积频率曲线法两种方法,计算了这一区域土壤重金属的地球化学基线值,并利用富集因子来评价当地的重金属污染状态.结果表明,除极少数样品外,这一区域绝大多数样品并未受到明显的人为污染.乔口镇地处湘江下游,其地球化学基线值可以为长沙-株洲-湘潭(简称长-株-潭)经济区的土壤重金属污染提供参考.

Elevated concentrations of heavy metals in top soils are found along with the development of industry and urbanization. Geochemical baseline of heavy metals in soil,an index of distinguishing natural background with anthropogenic activities,provides an important reference for assessment of soil contamination. In this study,the geochemical baseline of heavy metals in the soils of Qiaokou town,Changsha city,Hunan Province were obtained by methods of normalization and cumulative frequency curves,these baselines were then further used as the basic reference in enrichment factor( EF)analysis for assessment of heavy metal contamination in this area. The results showed that most of the samples were not contaminated. As Qiaokou is located in the downstream of Xiangjiang River,the geochemical baseline could be an important reference for assessing the heavy metal contamination in the Changsha-Zhuzhou-Xiangtan area.