Details
Original language | English |
---|---|
Article number | 176196 |
Journal | Science of the Total Environment |
Volume | 954 |
Early online date | 13 Sept 2024 |
Publication status | E-pub ahead of print - 13 Sept 2024 |
Abstract
The mechanisms governing bacteria transport and fate rely on their hydrophobicity and the wettability of porous media across a wide range of soil moisture conditions, extending from extreme dryness to highly saturated states. However, it largely remains unknown how transport, retention, and release mechanisms change in natural soil systems in such conditions. We thus optimized our previously published unique transport data for hydrophilic Escherichia coli (E. coli) and hydrophobic Rhodococcus erythropolis (R. erythropolis) bacteria, and bromide (Br−) in two distinct wettable and water-repellent soils at column scale. The soils were initially dry, followed by injecting influents in two pulses followed by a flushing step under saturated flow conditions for six pore volumes. We conducted simulations for each pulse separately and simultaneously for soils. There were differences in hydraulic properties of the soils due to their contrasting wetting characteristic in separate and simultaneously modeling of each pulse affecting Br− and bacteria transport fate. Bacteria attachment was the dominant retention mechanism in both soils in these conditions. Notably, the 82.4 min−1 attachment rate in wettable soil was almost 10× greater than in the water-repellent soil and it governed optimization of bacteria die-off. Physicochemical detachment and physical release unraveled the effect of bacteria size and hydrophobicity interacting with soil wettability. The smaller and hydrophobic R. erythropolis detached more easily while hydrophilic E. coli released; the rates were enhanced by soil water repellency. Further research is needed to reveal the effects of surface wettability properties on bacteria survival especially at the nanoscale.
Keywords
- Attachment, Bacteria, Straining, Transport processes, Water repellency, Wettability
ASJC Scopus subject areas
- Environmental Science(all)
- Environmental Engineering
- Environmental Science(all)
- Environmental Chemistry
- Environmental Science(all)
- Waste Management and Disposal
- Environmental Science(all)
- Pollution
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In: Science of the Total Environment, Vol. 954, 176196, 01.12.2024.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Modeling bacterial transport and fate
T2 - Insight into the cascading consequences of soil water repellency and contrasting hydraulic conditions
AU - Sepehrnia, Nasrollah
AU - Teshnizi, Forough Abbasi
AU - Hallett, Paul
AU - Coyne, Mark
AU - Shokri, Nima
AU - Peth, Stephan
N1 - Publisher Copyright: © 2024 The Authors
PY - 2024/9/13
Y1 - 2024/9/13
N2 - The mechanisms governing bacteria transport and fate rely on their hydrophobicity and the wettability of porous media across a wide range of soil moisture conditions, extending from extreme dryness to highly saturated states. However, it largely remains unknown how transport, retention, and release mechanisms change in natural soil systems in such conditions. We thus optimized our previously published unique transport data for hydrophilic Escherichia coli (E. coli) and hydrophobic Rhodococcus erythropolis (R. erythropolis) bacteria, and bromide (Br−) in two distinct wettable and water-repellent soils at column scale. The soils were initially dry, followed by injecting influents in two pulses followed by a flushing step under saturated flow conditions for six pore volumes. We conducted simulations for each pulse separately and simultaneously for soils. There were differences in hydraulic properties of the soils due to their contrasting wetting characteristic in separate and simultaneously modeling of each pulse affecting Br− and bacteria transport fate. Bacteria attachment was the dominant retention mechanism in both soils in these conditions. Notably, the 82.4 min−1 attachment rate in wettable soil was almost 10× greater than in the water-repellent soil and it governed optimization of bacteria die-off. Physicochemical detachment and physical release unraveled the effect of bacteria size and hydrophobicity interacting with soil wettability. The smaller and hydrophobic R. erythropolis detached more easily while hydrophilic E. coli released; the rates were enhanced by soil water repellency. Further research is needed to reveal the effects of surface wettability properties on bacteria survival especially at the nanoscale.
AB - The mechanisms governing bacteria transport and fate rely on their hydrophobicity and the wettability of porous media across a wide range of soil moisture conditions, extending from extreme dryness to highly saturated states. However, it largely remains unknown how transport, retention, and release mechanisms change in natural soil systems in such conditions. We thus optimized our previously published unique transport data for hydrophilic Escherichia coli (E. coli) and hydrophobic Rhodococcus erythropolis (R. erythropolis) bacteria, and bromide (Br−) in two distinct wettable and water-repellent soils at column scale. The soils were initially dry, followed by injecting influents in two pulses followed by a flushing step under saturated flow conditions for six pore volumes. We conducted simulations for each pulse separately and simultaneously for soils. There were differences in hydraulic properties of the soils due to their contrasting wetting characteristic in separate and simultaneously modeling of each pulse affecting Br− and bacteria transport fate. Bacteria attachment was the dominant retention mechanism in both soils in these conditions. Notably, the 82.4 min−1 attachment rate in wettable soil was almost 10× greater than in the water-repellent soil and it governed optimization of bacteria die-off. Physicochemical detachment and physical release unraveled the effect of bacteria size and hydrophobicity interacting with soil wettability. The smaller and hydrophobic R. erythropolis detached more easily while hydrophilic E. coli released; the rates were enhanced by soil water repellency. Further research is needed to reveal the effects of surface wettability properties on bacteria survival especially at the nanoscale.
KW - Attachment
KW - Bacteria
KW - Straining
KW - Transport processes
KW - Water repellency
KW - Wettability
UR - http://www.scopus.com/inward/record.url?scp=85203872637&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2024.176196
DO - 10.1016/j.scitotenv.2024.176196
M3 - Article
C2 - 39278475
AN - SCOPUS:85203872637
VL - 954
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
M1 - 176196
ER -