HR: 14:10h
AN: H13I-03    [Abstracts]
TI: Use of Bioluminescence to Study Reactive Solute Transport and Biofilm Growth and Activity in Porous Media
AU: Sharp, R R
EM: Robert.sharp@manhattan.edu
AF: Manhattan College Department of Civil and Environmental Engineering, Leo Engineering Hall, Bronx, NY 10471 United States
AU: * Gerlach, R
EM: robin_g@erc.montana.edu
AF: Montana State University Center for Biofilm Engineering, 366 EPS Building, Bozeman, MT 59717 United States
AU: Al, C B
EM: al_c@erc.montana.edu
AF: Montana State University Center for Biofilm Engineering, 366 EPS Building, Bozeman, MT 59717 United States
AB: Using a meso-scale porous media flat plate reactor we utilized a naturally bioluminescent biofilm (V. fischeri) and tracer studies to obtain information on the interactions between biofilms and reactive flow in porous media. The growth and development of the V. fischeri biofilm in a porous media geometry was studied using digital time lapse images of the bioluminescent signal given off by the developing biofilm. The effect of biofilm development on porous media hydrodynamics was examined using dye tracer studies and image analysis. The natural bioluminescence of the V. fischeri allowed real-time, in-situ study of biofilm development in porous media, without destruction of the biofilm. Dye studies and image analysis enabled the study of effects of biofilm accumulation on porous media hydraulics, with comparisons to plug flow and completely mixed systems with varying degrees of biofilm accumulation. The hydraulic conductivity of the porous media/biofilm system was continuously monitored showing a 1 to 4 order of magnitude decrease in hydraulic conductivity as a function of biofilm thickness and accumulation. The real-time nature of the study permitted us to visualize dynamic flow channel formation within the biofilm/porous media system. In addition, the sensitivity of the V. fischeri biofilm to dissolved oxygen allowed us to capture real-time images of reactive transport within the system. Using bioluminescent imaging, the location of active biomass, as well as the relative degree of biological activity, could be visualized and monitored over time. This work is the first meso-scale visualization of the interactions between biofilm and flow in porous media.
DE: 1899 General or miscellaneous
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting