生态环境学报 ›› 2021, Vol. 30 ›› Issue (11): 2232-2243.DOI: 10.16258/j.cnki.1674-5906.2021.11.014

• 研究论文 • 上一篇    下一篇

广西露天铝土矿区复垦地土壤重金属空间分布特征及风险评价

崔丽蓉1(), 叶丽丽1, 陈永山2, 闫超凡1, 蒋金平1,3,*()   

  1. 1.广西环境污染控制理论与技术重点实验室,广西 桂林 541004
    2.泉州师范学院资源与环境科学学院,福建 泉州 362000
    3.广西岩溶地区水污染控制用水安全保障协同创新中心,广西 桂林 541004
  • 收稿日期:2021-06-16 出版日期:2021-11-18 发布日期:2021-12-29
  • 通讯作者: * 蒋金平(1972年生),男,研究员,博士,主要从事土壤环境与污染修复研究工作。E-mail: jiangjinping74@163.com
  • 作者简介:崔丽蓉(1996年生),女,硕士研究生,主要从事土壤环境与污染修复研究工作。E-mail: 296079239@qq.com
  • 基金资助:
    国家自然科学基金项目(41661097);广西自然科学基金项目(2020GXNSFAA297124)

Spatial Distribution Characteristics and Pollution Assessment of Heavy Metals in Reclaimed Land of A Bauxite Mine Region in Guangxi

CUI Lirong1(), YE Lili1, CHEN Yongshan2, YAN Chaofan1, JIANG Jinping1,3,*()   

  1. 1. Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin 541004, China
    2. School of Resources and Environmental Science, Quanzhou Normal University, Quanzhou 362000, China
    3. Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin 541004, China
  • Received:2021-06-16 Online:2021-11-18 Published:2021-12-29

摘要:

有色金属矿开采后复垦土地污染状况评估对其安全利用具有重要意义。为了查明广西典型露天铝土矿复垦土壤的环境质量状况,对平果铝矿采空区不同时期复垦土壤(A区1998年复垦;B区2003年复垦;C区2013年复垦)的肥力因子、重金属含量、空间分布、污染程度及生态风险进行研究。结果表明,铝土矿区复垦土壤肥力较低,与C区土壤养分相比,A区和B区土壤有不同程度的提高。不同复垦区土壤Hg、Cd、Cr、Pb、As平均含量均超过了广西土壤背景值,且Cd、As是农用地筛选值的6.67—16.03、2.42—4.10倍,重金属存在高度的空间变异。复垦土壤中Al含量较高,是广西背景值的1.51、1.65、1.36倍。活性Al质量分数最小,为4722.65 mg∙kg-1,已超过部分植物的铝毒临界值,对植物产生了一定的影响。污染负荷指数结果表明,铝土矿复垦区土壤均属于重度污染。潜在生态风险评价结果显示,B区处于中等环境风险水平,而A区和C区仍处于较强生态风险水平。健康风险评价结果表明,通过摄食途径重金属对儿童健康危害程度比成人高;致癌重金属As对人群危害大于Cd。平果铝矿复垦土壤受到重金属的污染,对周边环境及人群产生一定的危害。因此,该铝土矿复垦地在安全利用的过程中,需要不断改良以降低复垦土壤的生态风险。

关键词: 复垦土壤, 铝土矿, 空间分布, 重金属, 风险评价

Abstract:

The assessment of pollution status of reclaimed land after non-ferrous metal mining is of great significance to its safe utilization. In order to find out the environmental quality of reclaimed soil of typical open-pit bauxite mines in Guangxi, the fertility factors, heavy metal content, spatial distribution, pollution degree and ecological risk of reclaimed soil in different periods in mined-out areas of Pingguo aluminum mine (area A: reclaimed in 1998; area B: reclaimed in 2003; area C: reclaimed in 2013) were studied. The results show that the soil fertility in reclamation area is low. Compared with the soil fertility in C area, the soil in area A and B has been improved to different extents. The average content of soil Hg, Cd, Cr, Pb and As in the reclaimed area exceeds the background values of Guangxi, and Cd and As are 6.67?16.03 times, 2.42-4.10 times of the screening values of agricultural land. There is a high degree of spatial variation of metals in the reclaimed soil. The content of Al in reclaimed soil is high, which is 1.51 times, 1.65 times and 1.36 times of the background value of Guangxi. The minimum content of active Al is 4722.65 mg∙kg-1, which has exceeded the toxicity threshold of some plants and has a certain impact on plants. The pollution load index results show that the soil in bauxite reclamation area is heavy pollution. The potential ecological risk assessment shows that the area B belongs to medium environmental risk, while the area A and area C is still at a strong level of ecological risk. The results of health risk assessment show that heavy metals are more harmful to children’s health than adults through feeding, and carcinogenic heavy metal As is more harmful to people than Cd. The reclaimed soil of Pingguo aluminum mine is polluted by heavy metal, which causes some harm to the surrounding environment and people. Therefore, in the process of safe utilization, the bauxite reclamation land needs continuous improvement to reduce the ecological risk of the reclaimed soil.

Key words: reclamation land, bauxite, spatial differentiation, heavy metal, risk assessment

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