结合多种高分辨率现场技术,了解淹水工业土壤中无氧-氧接口的金属动员情况
Danxing Yang1, Hao Zhang2, Wen Fang1
1State Key Laboratory of Water Pollution Control and Green Resource Recycling, School of Environment, Nanjing University, Jiangsu 210023, China.
Journal of hazardous materials
|July 11, 2025
概括
气候变化影响沿海工业土壤,改变了氧化还原条件和重金属 (HM) 的可用性. 土壤的特性极大地影响了HM在无氧-氧接口的动员,这对现场修复至关重要.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 地质化学 地质化学
背景情况:
- 沿海地区的工业场所由于气候变化而面临着波动性的氧化还原条件.
- 这些氧化还原转移会产生无氧-氧接口,影响重金属 (HM) 的可用性.
- 了解受氧和土壤特性影响的HM动员对于管理受污染的地点至关重要.
研究的目的:
- 研究工业土壤中无氧氧接口的重金属 (Fe,Mn,Cu,Ni,Zn) 调动机制.
- 确定不同氧气水平和土壤物理化学特性如何影响不同土壤深度的HM行为.
- 阐明微观氧化还原动力学在受污染的工业土壤中的HM流动性中的作用.
主要方法:
- 利用高分辨率的现场技术:平面 optodes (PO) 用于 O2 和 pH 映射,以及薄膜扩散梯度 (DGT) 用于 HM 分析.
- 在表面泥土土壤中比较O2扩散和HM调动模式,与深层泥土土壤中的泥土土壤相比.
- 相关联观察到的HM动员与在无氧-氧接口上测量的O2和pH梯度.
主要成果:
- 平面 optodes 揭示了与深层土壤相比,表面土壤中的 O2 扩散更大.
- 表面土壤呈现出快速的Fe (II) /Mn (II) 氧化,由于高污染和溶解有机碳 (DOC),Cu,Ni和Zn保持稳定.
- 深层土壤在无氧-氧接口处表现出显著的Cu,Ni和Zn动员,与O2和pH波动直接相关.
结论:
- 土壤特性和微尺度氧化还原动力学是工业土壤中重金属行为的关键决定因素.
- 在表面和深层土壤之间观察到的明显的HM动员模式突显了深度依赖分析的重要性.
- 调查结果为污染工业场所的有效管理和整治策略提供了必要的见解.
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