title: Using bacterial bioluminescence to evaluate the impact of biofilm on porous media hydraulic properties.
abstract: Biofilm formation in natural and engineered porous systems can significantly impact hydrodynamics by reducing porosity and permeability. To better understand and characterize how biofilms influence hydrodynamic properties in porous systems, the genetically engineered bioluminescent bacterial strain Pseudomonas fluorescens HK44 was used to quantify microbial population characteristics and biofilm properties in a translucent porous medium. Power law relationships were found to exist between bacterial bioluminescence and cell density, fraction of void space occupied by biofilm (i.e. biofilm saturation), and hydraulic conductivity. The simultaneous evaluation of biofilm saturation and porous medium hydraulic conductivity in real time using a non-destructive approach enabled the construction of relative hydraulic conductivity curves. Such information can facilitate simulation studies related to biological activity in porous structures, and support the development of new models to describe the dynamic behavior of biofilm and fluid flow in porous media. The bioluminescence based approach described here will allow for improved understanding and control of industrially relevant processes such as biofiltration and bioremediation.
authors.affiliation: Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
authors.forename: Ali
authors.initials: A
authors.lastname: Bozorg
authors.affiliation: Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
authors.forename: Ian D
authors.initials: ID
authors.lastname: Gates
authors.affiliation: Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada. Electronic address: asen@ucalgary.ca.
authors.forename: Arindom
authors.initials: A
authors.lastname: Sen
mesh_terms: D001431:Bacteriological Techniques / Q000379:methods*; D018441:Biofilms / Q000254:growth & development*; D006874:Hydrostatic Pressure; D008163:Luminescent Measurements / Q000379:methods*; D011551:Pseudomonas fluorescens / Q000737:chemistry / Q000502:physiology*; D012212:Rheology / Q000379:methods*
keywords: Biofilm; Biofilm saturation; Bioluminescence; Porous medium; Relative hydraulic conductivity curve