Speaker
Description
The increasing accumulation of microplastics (MPs) in soils has raised concern about their potential to alter subsurface transport processes [1,2] that regulate nutrient and contaminant mobility. This study investigates how microplastic contamination influences solute transport dynamics in sandy soils by integrating laboratory soil column experiments with pore-scale microfluidic observations [3]. Polyethylene (PE) and polyvinylchloride (PVC) MPs were thoroughly mixed with soil at 2% and 5% (mass basis) to quantify their effects on solute breakthrough behavior. Tracer transport experiments using NaCl revealed that MP contamination led to early solute breakthrough and delayed peak concentrations relative to pure sand samples. Averaged across all samples, the mean diffusion-dispersion coefficient increased from approximately 0.0097 cm2/s in pure sand to 0.0223 cm2/s at 2% and 0.0358 cm2/s at 5% MP concentrations, indicating 2.3- and 3.7-fold increases, respectively. Confocal and fluorescence microscopy of synthesized porous media showed accumulation of MPs and clogging of pore spaces which increased pore-scale flow heterogeneity. These microstructural changes enhanced solute dispersion and promoted the development of preferential flow paths, providing mechanistic insight into the observed macroscopic transport processes in MP-contaminated soils.
References
[1] Jannesarahmadi, S.; Aminzadeh, M., Raga, R., Shokri, N. (2023). Effects of microplastics on evaporation dynamics in porous media, Chemosphere, 311, 137023, https://doi.org/10.1016/j.chemosphere.2022.137023
[2] Aminzadeh, M., Kokate, T., Shokri, N. (2025). Microplastics in Sandy Soils: Alterations in Thermal Conductivity, Surface Albedo, and Temperature, Environmental Pollution, 372, 125956, https://doi.org/10.1016/j.envpol.2025.125956
[3] Aminzadeh, M., Kokate, T., Chaudhry, A.U., Rabbani, H., Bijeljic, B., Blunt, M.J., Shokri, N. (2025). Microplastic-induced alterations in water flow and solute transport dynamics in soil. Scientific Reports, 15, 42941, https://doi.org/10.1038/s41598-025-30476-6
| Country | Germany |
|---|---|
| Acceptance of the Terms & Conditions | Click here to agree |
