Biodegradation Kinetics of Benzene and Naphthalene in the Vadose and Saturated Zones of a (Semi)-arid Saline Coastal Soil Environment
Table 3
Mass balance between oxygen and nitrate consumption and petroleum hydrocarbon degradation.
Compound
Soil and environmental condition
Electron acceptor
Observed lowest concentration of an electron acceptor in biotic samples (mmol L-1)
Observed maximum consumption of an electron acceptor (mmol L-1)
Maximum concentration of PHCs biodegraded based on maximum electron acceptor consumed# (mmol L-1)
Observed actual maximum concentration of PHCs biodegraded in the experiment including an assumed contribution of SRB (mmol L-1)
Benzene
A1 (low salinity)
O2
0.005
0.053
0.007
0.051
NO3-
0
0.083
0.006
A2 (low salinity)
O2
0.009
0.049
0.007
0.062
NO3-
0
0
0
A3 (low salinity)
O2
0.020
0.038
0.005
0.050
NO3-
0
0.068
0.005
A3 (high salinity)
O2
0.011
0.048
0.006
—
0.046
NO3-
No data
No data
No data
Naphthalene
A1 (low salinity)
O2
0
0.058
0.005
0.009
NO3-
0
0.068
0.003
A2 (low salinity)
O2
0.037
0.022
0.002
0.025
NO3-
0
0.037
0.002
A3 (low salinity)
O2
0.004
0.054
0.005
0.019
NO3-
0
0.073
0.003
A3 (high salinity)
O2
0.025
0.033
0.003
—
0.012
NO3-
No data
No data
No data
The evaluation was performed with the mean concentrations of triplicate biotic samples and duplicate controls. The consumption or losses of O2 and NO3- are reductions from the initial concentration of O2 and concentrations of NO3- in controls, respectively. #The calculations were based on the stoichiometry ratios in Equations (1) and (2) and (5) and (6).
