TY - JOUR
T1 - Linking Spectral Induced Polarization (SIP) and Subsurface Microbial Processes
T2 - Results from Sand Column Incubation Experiments
AU - Mellage, Adrian
AU - Smeaton, Christina M.
AU - Furman, Alex
AU - Atekwana, Estella A.
AU - Rezanezhad, Fereidoun
AU - Van Cappellen, Philippe
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/2/20
Y1 - 2018/2/20
N2 - Geophysical techniques, such as spectral induced polarization (SIP), offer potentially powerful approaches for in situ monitoring of subsurface biogeochemistry. The successful implementation of these techniques as monitoring tools for reactive transport phenomena, however, requires the deconvolution of multiple contributions to measured signals. Here, we present SIP spectra and complementary biogeochemical data obtained in saturated columns packed with alternating layers of ferrihydrite-coated and pure quartz sand, and inoculated with Shewanella oneidensis supplemented with lactate and nitrate. A biomass-explicit diffusion-reaction model is fitted to the experimental biogeochemical data. Overall, the results highlight that (1) the temporal response of the measured imaginary conductivity peaks parallels the microbial growth and decay dynamics in the columns, and (2) SIP is sensitive to changes in microbial abundance and cell surface charging properties, even at relatively low cell densities (<108 cells mL-1). Relaxation times (τ) derived using the Cole-Cole model vary with the dominant electron accepting process, nitrate or ferric iron reduction. The observed range of τ values, 0.012-0.107 s, yields effective polarization diameters in the range 1-3 μm, that is, 2 orders of magnitude smaller than the smallest quartz grains in the columns, suggesting that polarization of the bacterial cells controls the observed chargeability and relaxation dynamics in the experiments.
AB - Geophysical techniques, such as spectral induced polarization (SIP), offer potentially powerful approaches for in situ monitoring of subsurface biogeochemistry. The successful implementation of these techniques as monitoring tools for reactive transport phenomena, however, requires the deconvolution of multiple contributions to measured signals. Here, we present SIP spectra and complementary biogeochemical data obtained in saturated columns packed with alternating layers of ferrihydrite-coated and pure quartz sand, and inoculated with Shewanella oneidensis supplemented with lactate and nitrate. A biomass-explicit diffusion-reaction model is fitted to the experimental biogeochemical data. Overall, the results highlight that (1) the temporal response of the measured imaginary conductivity peaks parallels the microbial growth and decay dynamics in the columns, and (2) SIP is sensitive to changes in microbial abundance and cell surface charging properties, even at relatively low cell densities (<108 cells mL-1). Relaxation times (τ) derived using the Cole-Cole model vary with the dominant electron accepting process, nitrate or ferric iron reduction. The observed range of τ values, 0.012-0.107 s, yields effective polarization diameters in the range 1-3 μm, that is, 2 orders of magnitude smaller than the smallest quartz grains in the columns, suggesting that polarization of the bacterial cells controls the observed chargeability and relaxation dynamics in the experiments.
UR - http://www.scopus.com/inward/record.url?scp=85042315024&partnerID=8YFLogxK
U2 - 10.1021/acs.est.7b04420
DO - 10.1021/acs.est.7b04420
M3 - 文章
C2 - 29336556
AN - SCOPUS:85042315024
SN - 0013-936X
VL - 52
SP - 2081
EP - 2090
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 4
ER -