生态环境学报 ›› 2023, Vol. 32 ›› Issue (6): 1123-1132.DOI: 10.16258/j.cnki.1674-5906.2023.06.014

• 研究论文 • 上一篇    下一篇

旱区盐湖盆地土壤重金属空间变异及对土壤理化因子的响应

杜丹丹1,2(), 高瑞忠1,2,*(), 房丽晶1, 谢龙梅1   

  1. 1.内蒙古农业大学水利与土木建筑工程学院,内蒙 古呼和浩特 010018
    2.黄河流域内蒙段水资源与水环境综合治理自治区协同创新中心,内蒙古 呼和浩特 010018
  • 收稿日期:2022-12-16 出版日期:2023-06-18 发布日期:2023-09-01
  • 通讯作者: *高瑞忠(1977年生),男,教授,博士,主要从事水资源评价、生态水文过程模拟研究。E-mail: ruizhonggao@qq.com
  • 作者简介:杜丹丹(1968年生),女,高级实验师,硕士,主要从事土壤、水环境污染物的监测与分析评价的教学与研究。E-mail: duddpublic@163.com
  • 基金资助:
    国家自然科学基金项目(51969022);国家自然科学基金项目(52169004);内蒙古科技攻关项目(2019GG141)

Spatial Variation of Soil Heavy Metals and Their Responses to Physicochemical Factors of Salt Lake Basin in Arid Area

DU Dandan1,2(), GAO Ruizhong1,2,*(), FANG Lijing1, XIE Longmei1   

  1. 1. Institute of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Hohhot 010018, P. R. China
    2. Autonomous Region Collaborative Innovation Center for Integrated Management of Water Resources and Water Environment in the Inner Mongolia Reaches of the Yellow River, Hohhot 010018, P. R. China
  • Received:2022-12-16 Online:2023-06-18 Published:2023-09-01

摘要:

为探明盐湖盆地土壤重金属铬(Cr)、汞(Hg)、砷(As)的分布特征及在其理化因素影响下呈现的分异规律,以内蒙吉兰泰盐湖盆地为研究区,采集土壤表层、50 cm、100 cm等不同土层深度150个样本,对Cr、Hg、As和土壤理化指标进行测试,以地统计学解析不同剖面土壤重金属空间变异特征及分布规律,运用多元统计和冗余分析法解释土壤中各土层重金属与土壤pH、TDS、TN、θ、土壤分形维数D等理化指标的赋存相关性。结果表明,土壤重金属Cr、Hg、As含量分别介于2.90—63.5、0.002—0.602、0.02—21.8 mg·kg-1之间,变幅较大;Cr、Hg、As的内蒙古地区背景值均在各层最大值和最小值之间,存在Cr、Hg、As的超标点或局部超标区域;各层土壤的Cr、Hg、As含量均在国家土壤污染风险管控标准范围之内;各土层Cr、Hg和100 cm处As的空间分布特征具有强烈的空间自相关性,土壤母质、气候环境等自然因素是土壤Cr、Hg、As含量的主要影响因素;As在表层、50 cm层属中等程度的空间自相关,空间变异是自然因素和随机因素的协同作用驱动所致;各层土壤理化指标对重金属变异特征影响效应具有相同的规律,贡献率排序D>pH>TDS>TN>θ,其中土壤分形维数D对土壤重金属的影响起主导性作用;在所有土层中分形维数对Cr、As产生正向影响,对Hg产生负向影响,达到极显著水平0.002(P<0.01)。研究成果可为旱区盐湖盆地土壤污染修复提供技术支持,为保护区域生态环境安全提供理论依据。

关键词: 重金属, 土壤理化性质, 分形维数, 地统计学, 冗余分析, 盐湖盆地

Abstract:

In order to explore the distribution characteristics of heavy metals, chromium (Cr), mercury (Hg) and arsenic (As), in the soil of the salt lake basin and their differentiations under the influence of physicochemical factors, the Jilantai salt lake basin in Inner Mongolia was chosen as the study area, and 150 samples of different soil depths, such as the surface layer, 50 cm, 100 cm, were collected and the Cr, Hg, As and soil physicochemical indicators were tested. The spatial variation characteristics and distribution of heavy metals in different soil profiles were analyzed by geostatistics, and multivariate statistics and redundancy analysis were used to explain the relationships between heavy metals and pH, TDS, TN, θ, and soil fractal dimension (D). The results showed that the contents of Cr, Hg and As in soil were 2.90-63.5 mg·kg-1, 0.002-0.602 mg·kg-1 and 0.02-21.8 mg·kg-1, respectively, with large variations; the background values of Cr, Hg and As in Inner Mongolia were between the maximum and minimum values of each layer content, so there were over-standard points or local areas; the contents of Cr, Hg and As in each layer of soil were within the scope of National Soil Pollution Risk Control Standards; the spatial distribution characteristics of Cr and Hg in each soil layer and As at 100 cm showed strong spatial autocorrelations; the natural factors such as soil parent material and climate environment were the main influencing factors for soil Cr, Hg and As content; As in the surface layer and 50 cm layer showed medium spatial autocorrelations, and the spatial variation was driven by the synergy of natural factors and random factors; the effect of soil physicochemical indexes on the variation characteristics of heavy metals followed the same rule, and the contribution rate was ranked as D>pH>TDS>TN>θ, in which the D played the main role; in all soil layers, D showed positive impact on Cr and As and negative impact on Hg, and the effects were highly significant (P=0.002). This study can provide technical support for the soil pollution remediation of the salt lake basin and theoretical basis for the protection of regional ecological environment security in arid areas.

Key words: heavy metals, physicochemical properties of soil, fractal dimension, geostatistics, redundancy analysis, salt lake basin

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