地理科学 ›› 2015, Vol. 35 ›› Issue (3): 380-386.doi: 10.13249/j.cnki.sgs.2015.03.380

• 论文 • 上一篇    

长江北支口门圆陀角附近潮滩沉积物重金属来源及污染评价

谢丽1, 张振克2   

  1. 1. 广东财经大学地理与旅游学院, 广东广州510320;
    2. 南京大学地理与海洋科学学院南京大学海岸与海岛开发教育部重点实验室, 江苏南京210093
  • 收稿日期:2014-08-18 修回日期:2014-10-17 出版日期:2015-03-20 发布日期:2015-03-20
  • 作者简介:谢丽(1978-),女,安徽六安人,博士,讲师,主要从事海岸带沉积环境研究。E-mail:Li_xie361@126.com
  • 基金资助:

    国家自然科学基金(41371024,41230751,41071006)、广东省自然科学基金(S2013040015299)、国家科技支撑计划项目(2012BAC07B01)、高等学校博士点基金项目(20100091110011)资助。

Sources and Pollution Assessment of Heavy Metals in the Sediments of the Tidal Flat at the Yuantuojiao Point, the North Branch, Changjiang River

XIE Li1, ZHANG Zhen-ke2   

  1. 1. School of Geography and Tourism, Guangdong University of Finance & Economics, Guangzhou, Guangdong 510320, China;
    2. School of Geographic and Oceanographic Sciences, Key Laboratory of Ministry of State Education for Coast and Island Development, Nanjing University, Nanjing, Jiangsu 210093, China
  • Received:2014-08-18 Revised:2014-10-17 Online:2015-03-20 Published:2015-03-20

摘要:

:基于圆陀角附近潮滩YY孔岩芯重金属(Co、Cr、Cu、Mn、Ni、V、Zn)富集系数和人为贡献率、地累积指数和潜在生态风险系数,讨论了圆陀角附近潮滩重金属来源及污染。结果表明,重金属Co、V平均含量显著高于背景值。除Cr 是自然来源外,其它6 种重金属受自然和人为来源的影响,且以自然来源为主。7 种重金属总体无污染,仅Co、Cu、V和Zn在岩芯132 cm处出现无污染至中度污染。7 种重金属潜在生态危害属轻微水平。值得关注的是,1997 年之后,重金属Co、Cr、Mn、V、Zn地累积指数和潜在生态风险系数均有增加的趋势。

关键词: 重金属来源, 地累积指数, 圆陀角, 潮滩, 潜在生态风险系数

Abstract:

The North Branch, separated by the Chongming Island, was once the main channel in the estuary of the Changjiang River. The human reclamation and the south migration of the main channel led to the narrowing and shallowing of the North Branch. Yuantuojiao Point is the intersecting point of the North Branch of the Changjiang River with the South Yellow Sea coastal line. The specific geographic location and the complexity of regional morphological dynamics developed a typical silt-mud tidal flat. Heavy metals contents of the tidal- flat sediments recorded rich information of the coastal environmental changes near the Yuantuojiao Point. In this study, the heavy metals sources and pollution evolution were discussed according to the heavy metals contents within the tidal-flat sediments at the Yuantuojiao Point. A drilling core of 218 cm was collected on the salt marsh at the Yuantuojiao Point. The grain size and 7 heavy metals (Co, Cr, Cu, Mn, Ni, V, Zn) of the YY core were measured. The chronology of this core was built by using the 137Cs dating. The correlation analysis, enrichment coefficient, human contribution rate, geo-accumulation index, and potential ecological risk coefficient of the heavy metals from the YY core were calculated. The results show the contents of heavy metals were lower after 1960, but were higher before 1960. The average content of V was significantly higher than the background and the content of Co is higher than the background for more than 100%. The average content of 7 heavy metals was most obviously higher than the background value at the depths of 132 cm of the YY core. The content of 7 heavy metals had a good relationship with grain size, indicating of the obvious"grain size control effect", and the heavy metals might have more coherent sources. The human contribution rates of 7 heavy metals from the sediments further proved that Cr was completely influenced by natural sources, the other 6 heavy metals contents were co-affected by the natural and artificial sources, but the natural source was still the main one. According to the environmental quality standard, the sediments are of no pollution for most heavy metals, but the sediments of the depths of 132 cm in the YY core were of free to moderate pollution for Co, Cu, V and Zn. The potential ecological risk level of 7 heavy metals was mild. However, the potential ecological risk coefficient and geo-accumulation index was higher before 1960 than that of after 1960. It is worthy to note that geo-accumulation index and potential ecological risk coefficient of 5 heavy metals (Co, Cr, Mn, V, and Zn) of the YY core show an increasing tendency after 1997. The accelerated accumulation of heavy metals at the Yuantuojiao Point should be paid attention. And the emission of heavy metals with larger toxicity coefficient should be reduced.

Key words: heavy metals sources, Yuantuojiao Point, tidal flat, geo-accumulation index, potential ecological risk coefficient

中图分类号: 

  • P951