地学前缘 ›› 2023, Vol. 30 ›› Issue (2): 514-525.DOI: 10.13745/j.esf.sf.2022.2.77

• 表层地球系统与生态环境效应 • 上一篇    下一篇

广东省汕头市土壤铬的空间分布特征、来源解析及影响因素研究

蒋兴超1,2(), 许静1,*(), 李如意1, 贾一凡1, 杨盼1, 罗杰1,2   

  1. 1.长江大学 油气资源与勘探技术教育部重点实验室, 湖北 武汉, 430100
    2.长江大学 油气地球化学与环境湖北省重点实验室, 湖北 武汉, 430100
  • 收稿日期:2022-02-10 修回日期:2022-04-04 出版日期:2023-03-25 发布日期:2023-01-05
  • 通讯作者: 许静
  • 作者简介:蒋兴超(1980—),男,博士,讲师,硕士生导师,主要从事地球化学方面的研究工作。E-mail: cjdx_jxc@163.com
  • 基金资助:
    国家自然科学基金项目(21876014);长江大学油气资源与勘探技术教育部重点实验室开放基金资助项目(PI2021-05)

Soil chromium in Shantou City, Guangdong Province: Spatial distribution characteristics, source apportionment and influencing factors

JIANG Xingchao1,2(), XU Jing1,*(), LI Ruyi1, JIA Yifan1, YANG Pan1, LUO Jie1,2   

  1. 1. Ministry of Education Key Laboratory of Exploration Technologies for Oil and Gas Resources, Yangtze University, Wuhan 430100, China
    2. Hubei Key Laboratory of Petroleum Geochemistry and Environment (Yangtze University), Wuhan 430100, China
  • Received:2022-02-10 Revised:2022-04-04 Online:2023-03-25 Published:2023-01-05
  • Contact: XU Jing

摘要:

汕头市是广东省的经济特区之一,是潮汕地区的政治、经济中心,拥有较高的工业化和城市化水平。以往对广东省的土壤环境质量研究主要集中在珠江三角洲,缺乏对韩江三角洲的土壤环境元素分布、来源的系统性调查和研究。为全面了解广东省汕头市土壤重金属Cr的污染状况,本文依照标准格网采集511个表层(0~20 cm)土壤样和139个深层(>150 cm)土壤样进行Cr含量检测,根据富集因子法分析表层土壤中Cr的污染情况,运用PCA分析表层土壤Cr的来源,克里金插值法及方差分析法对Cr的空间分布及其控制因素进行了分析。结果显示,Cr在浅层土壤的几何含量均值为32.40 mg·kg-1,低于汕头市土壤背景值39.52 mg·kg-1,远远低于《土壤环境质量 农用地土壤污染风险管控标准(试行)》(GB 15618—2018)中的Cr风险筛选值(300 mg·kg-1,6.5<pH≤7.5)。研究区大部分土壤为无富集和轻微富集,分别占66.34%和33.66%,无显著污染状况。汕头市潮南区的北部、潮阳区的北部及西南部为主要土壤Cr高值区,低值区分布于潮南区东部和濠江区东南沿海地区。通过PCA以及Pearson相关分析,推断汕头市内土壤Cr的来源是一种人为和自然的混合污染源,主要受成土母质影响。成土母质中三叠系砂岩的Cr含量比较高,白垩纪花岗岩的Cr含量较低;不同土壤类型中水稻土的Cr含量高,滨海砂土的Cr含量较低;不同土地利用类型中Cr含量差异不明显,人类活动对土壤Cr含量无明显影响。文中提供了汕头市土壤Cr的地球化学背景值,为后续相关研究奠定基础;同时综合多项指标推断Cr的物质来源及其占比,分析其影响因素,为后续判断是否出现Cr污染及制定相应防治对策提供参考。

关键词: 土壤铬, 污染, 空间分布特征, 影响因素, 汕头市

Abstract:

Shantou City, one of the special economic zones of Guangdong Province, is the economic and political center of Chaoshan area, with high level of industrialization and urbanization. In the past, soil environmental quality researches in Guangdong were mainly concentrated in the Pearl River Delta, while they lacked systemic investigation on the distribution and source apportionment of environmental soil elements in the Han River Delta. This study sought to assess the soil chromium (Cr) pollution status of Shantou City to aid prevention and control of Cr pollution in the area. According to the standard grid, 511 surface soil samples (0-20 cm) and 138 deep soil samples (>15 cm) were collected to determine the soil Cr contents. The Cr pollution status of surface soil was analyzed by the enrichment factor method, and the source of soil Cr was identified using PAC analysis; through Kriging interpolation and ANOVA, the spatial distribution characteristics of soil Cr and the influencing factors were explored. According to the results, the geometric mean content of Cr in the surface soil was 32.40 mg·kg-1, which is lower than the Cr background value for Shantou City (39.52 mg·kg-1) and much lower than the national Cr risk control standard (300 mg·kg-1, 6.5<pH≤7.5). Most of the soil samples showed no (66.34% samples) or slight (34.66% samples) Cr accumulation, with no obvious Cr contamination. The areas with high soil Cr values were mainly in the northern Chaonan District and northern and southwestern Chanyang District, and the lowest value areas were in the eastern Chaonan District and the coastal area of southeastern Haojiang District. PAC and Pearson’s correlation analysis results indicate the source of soil Cr in Shantou City is a combination of human activities and natural sources, mainly influenced by the soil parent material, with relatively high Cr in Triassic sandstone and low Cr in cretaceous granite. Cr content in paddy soil was higher than other soil types and relatively low in coastal sand soil, but there were no obvious differences between different land-use types; and human activities had no significant influence on soil Cr. The soil Cr background value obtained by this study laid a foundation for subsequent researches. Meanwhile by integrating multiple indicators this study accurately determined the source apportionment of soil Cr and analyzed its influencing factors, which provides an important reference for assessing Cr pollution and formulating the corresponding prevention measures.

Key words: soil Cr, pollution, spatial distribution characteristics, influencing factor, Shantou City

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