School of Energy and Environment, Inner Mongolia University of Science and Technology, Baotou 014010, People's Republic of China; Inner Mongolia Engineering Research Center of Evaluation and Restoration in the Mining Ecological Environments, Baotou 014010, People's Republic of China.
Zhejiang University of Technology Zhejiang Univ Technol, Coll Environm, Key Lab Microbial Technol Ind Pollut Control Zhej, Hangzhou 310014, People's Republic of China.
J Hazard Mater. 2021 Jun 5;411:125103. doi: 10.1016/j.jhazmat.2021.125103. Epub 2021 Jan 12.
Soil structure is an important index to evaluate soil quality; however, previous researchers have only paid attention to the effect and economic benefits of soil heavy metal remediation. In this study, microbial-induced carbonate precipitation (MICP) technology was used to remediate soil Pb pollution, and its effect on soil structure was studied by sieving and X-ray computed tomography techniques. The results showed that the leaching amount of heavy metals in soil decreased by 76.34% after remediation. Interestingly, due to the addition of organic matter and microorganisms, the soil particle size changed from microaggregates to large aggregates, and the large soil particle size (diameter > 2 mm) increased significantly by 71.43%. The soil porosity increased by 73.78%, which enhanced the soil permeability and increased the soil hydraulic conductivity. Therefore, MICP bioremediation not only remediated soil heavy metal pollution but also promoted the soil aggregation structure, which has important significance for soil remediation and improvement.
土壤结构是评估土壤质量的重要指标；然而，以往的研究只关注土壤重金属修复的效果和经济效益。本研究采用微生物诱导碳酸钙沉淀（MICP）技术修复土壤 Pb 污染，并通过筛分和 X 射线计算机断层扫描技术研究其对土壤结构的影响。结果表明，修复后土壤中重金属的浸出量减少了 76.34%。有趣的是，由于添加了有机物和微生物，土壤颗粒大小从微团聚体变为大团聚体，大土壤颗粒尺寸（直径>2mm）显著增加了 71.43%。土壤孔隙度增加了 73.78%，增强了土壤的渗透性，提高了土壤水力传导率。因此，MICP 生物修复不仅修复了土壤重金属污染，还促进了土壤团聚结构的形成，这对土壤修复和改良具有重要意义。
