地理学报 ›› 2017, Vol. 72 ›› Issue (5): 892-905.doi: 10.11821/dlxb201705010

• 土地利用与环境变化 • 上一篇    下一篇

开封古城不同朝代文化层重金属积累与污染分析

陈彦芳1(), 马建华1,2(), 刘德新1, 谷蕾1   

  1. 1. 河南大学资源与环境研究所,开封 475004
    2. 黄河文明河南省协同创新中心暨河南大学黄河文明与可持续发展研究中心,开封 475001
  • 收稿日期:2016-09-26 修回日期:2017-02-08 出版日期:2017-05-20 发布日期:2017-07-13
  • 作者简介:

    作者简介:陈彦芳(1990-), 女, 河南新郑人, 博士生, 主要从事土壤环境污染与防治研究。E-mail: yfchen0428@163.com

  • 基金资助:
    国家自然科学基金项目(41171409);教育部人文社会科学重点研究基地重大项目(12JJD790023);教育部和河南省共建河南大学项目(SBGJ090101)

Heavy metal enrichment and pollution of historical cultural layers in Kaifeng City, Henan Province

Yanfang CHEN1(), Jianhua MA1,2(), Dexin LIU1, Lei GU1   

  1. 1. Institute of Natural Resources and Environment, Henan University, Kaifeng 475004, Henan, China
    2. Collaborative Innovation Center on Yellow River Civilization of Henan Province & Key Research Institute of Yellow River Civilization and Sustainable Development, Henan University, Kaifeng 475001, Henan, China;
  • Received:2016-09-26 Revised:2017-02-08 Online:2017-05-20 Published:2017-07-13
  • Supported by:
    National Natural Science Foundation of China, No.41171409;Major Project of the Key Research Base of Human Science, National Educational Ministry of China, No.12JJD790023;Joint Project of the Ministry of Education of China and Henan Province for Developing Henan University, No.SBGJ090101

摘要:

开封古城黄泛沉积形成的“城摞城”奇观为文化层重金属积累与污染分析提供难得的材料。在开封市城区(师专钻孔和医专钻孔)和郊区(金明钻孔)分别获取25 m连续岩芯,大部分按10 cm间隔分样,共获得657个沉积物样品。用ICP-MS和AFS方法测定样品Pb、Cd、Cu、Zn、Hg、As、Ni、Cr和Co含量。结合地层14C年代数据、考古发掘及历史文献记载,建立不同朝代文化层年代框架,开展文化层重金属积累与污染分析。结果表明:师专、医专和金明钻孔均存在战国、宋金、明早期、明中期、明晚期和清代6个文化层。文化层大部分重金属发生不同程度富集,以Hg富集最为明显,城区钻孔明早期以前文化层达到强富集至极强富集水平。绝大多数文化层发生了重金属轻度至中度污染,中度污染发生在城区钻孔的宋金文化层。城区钻孔的最主要污染重金属是Hg,其次是Cu、Pb和Zn;郊区钻孔的主要污染重金属是Cd、Cr、Hg和Pb。不同朝代文化层重金属污染程度与其人口密度呈正相关。明早、中、晚期文化层污染程度逐渐减轻的现象可能与明朝开封城复兴与频繁的黄河泛滥有关。

关键词: 开封古城, 文化层, 重金属, 富集系数, 污染评价

Abstract:

Several dynasty palaces in Kaifeng City were buried by flood sediments of the Yellow River, forming the unique spectacle of city overlapping city, which were taken as excellent and rare samples to assess heavy metal enrichment and pollution of historical cultural layers. Three sedimentary cores with a length of 25 m were drilled in April, 2012, of which two were located in the urban area of Kaifeng City (ZKsz and ZKyz), and the other one was located in the western suburbs of the city (ZKjm). Each core was split into 10 cm intervals mostly, for a total of 657 soil samples. Concentrations of Pb, Cd, Cu, Zn, Ni, Cr and Co in samples were measured by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), while Hg and As were analyzed with Atomic Fluorescence Spectrometer (AFS). The dating frameworks of all the cultural layers in different dynasties were established according to AMS14C dates, archaeological explorations and historical documents. The results showed that six cultural layers were found in all the three sedimentary cores, including the Warring States, Song-Jin Dynasty, early Ming Dynasty, mid-Ming Dynasty, late Ming Dynasty and Qing Dynasty. Enrichment factors (EF) were calculated to assess the enrichment of heavy metals in cultural layers. Enrichment of most heavy metals occurred in the cultural layers, and Hg contributed to the highest enrichment level. Enrichment levels of Hg in the cultural layers of the two urban cores (ZKsz and ZKyz) before the early Ming Dynasty were from significant to extremely high. Pollution load index (PLI) was used to identify pollution levels of heavy metals in cultural layers. Most cultural layers showed slight to moderate pollution, while Song-Jin cultural layers of the two urban cores were considered as moderate pollution. Mercury was the main pollutant of the two urban cores while Cu, Pb and Zn had minor effects on the pollution, due to the wide use of cinnabar with high Hg contents in the history. As for the cultural layers of ZKjm core, Cd, Cr, Hg and Pb made more contributions to the pollution. The results also showed the positive linear relationships between metal PLI of cultural layers and their corresponding population densities. The decreasing PLI values from the early Ming to late Ming Dynasty were influenced probably by the frequent floods of the Yellow River.

Key words: Kaifeng City, cultural layer, heavy metal, enrichment factor, pollution assessment