Related Experiment Video
Updated: May 28, 2026
12:32
Combining Fluidic Devices with Microscopy and Flow Cytometry to Study Microbial Transport in Porous Media Across Spatial Scales
Published on: November 25, 2020
Spatial Organization of Biomass Controls Intrinsic Permeability of Porous Systems.
Wenqiao Jiao1,2, David Scheidweiler1,3, Nolwenn Delouche1
1Institute of Earth Science, University of Lausanne, Lausanne 1015, Switzerland.
Environmental Science & Technology
|May 27, 2026
Summary
Biofilm spatial organization, not just amount, controls porous media permeability. Motile bacteria confined biomass upstream, reducing permeability less than nonmotile bacteria, which colonized evenly.
Area of Science:
- Environmental microbiology
- Fluid dynamics
- Biogeochemistry
Background:
- Biofilms significantly alter porous media hydraulics, affecting groundwater remediation and industrial filtration.
- Existing knowledge links biomass accumulation to reduced permeability, but the role of spatial organization is unclear.
Purpose of the Study:
- To investigate the quantitative link between biofilm spatial organization and hydraulic property changes in porous media.
- To determine if biomass distribution, rather than total biomass, is the primary driver of permeability reduction.
Main Methods:
- Microfluidic experiments to visualize biofilm formation in a controlled porous environment.
- Time-lapse microscopy to track biofilm development and spatial distribution over time.
- Development and application of a novel mechanistic model to predict permeability changes based on biofilm structure.
Main Results:
- Motile *Pseudomonas putida* biofilms caused a 78% permeability reduction, while nonmotile mutant biofilms caused a 94% reduction, despite similar total biomass.
- Motile cells, by escaping nutrient-poor zones, formed upstream-confined biofilms, whereas nonmotile cells distributed homogeneously.
- The mechanistic model accurately predicted the observed permeability declines based on spatial biomass distribution.
Conclusions:
- Biofilm spatial distribution is the critical factor controlling permeability decline in porous media, not solely biomass abundance.
- Understanding biofilm spatial dynamics offers a new predictive framework for managing clogging in environmental and engineered systems.
- Differential colonization patterns of motile versus nonmotile bacteria highlight the importance of microbial behavior in system-scale hydraulic impacts.
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