Table 4.
Treatment | Methanogenic substrate | Well | Bottle | Substrate consumed inμmol | Measured methane | MCR |
---|---|---|---|---|---|---|
No substrate | Methanol | A3-11 | 1 | 725 (±40) | 407 | 1.8 |
2 | 712 (±70) | 341 | 2.1 | |||
C1-12 | 1 | 130 (±11) | 86 | 1.5 | ||
2 | 60 (±5) | 40 | 1.5 | |||
Methanol | Methanol | A3-11 | 1 | 3392 (±133) | 1858 | 1.8 |
2 | 3174 (±130) | 1361 | 2.3 | |||
B1-12 | 1 | 1620 (±165) | 418 | 3.9 | ||
2 | 4140 (±240) | 377 | 11.0 | |||
TMA* | TMA | A3-11 | 1 | 150 (±19) | 383 | 0.39 |
2 | 190 (±13.5) | 404 | 0.47 | |||
B1-12 | 1 | 181 (±5.1) | 365 | 0.50 | ||
2 | 144 (±15.4) | 409 | 0.35 | |||
Yeast extract* | Hydrogen | B1-12 | 1 | 15 | 39 | 0.38 |
2 | 16 | 45 | 0.36 | |||
C1-12 | 1 | 32 | 22 | 1.45 | ||
2 | 34 | 37 | 0.92 | |||
Formate* | Hydrogen | B1-12 | 1 | 211 | 74 | 2.90 |
2 | 311 | 85 | 3.66 |
Methane yields corrected for methane derived from methylotrophic methanogens after subtraction of the “no substrate” background. See Supplementary Figures S5, S6 for comparison. No MCRMeOH could be calculated for the B1-12 ”no substrate” and C1-12 “methanol” experiments. The low initial methanol concentration in the B1-12 well reached the detection limit at the time of sampling in the incubation experiment. The C1-12 well water incubated with methanol addition did not reach a methane plateau at the end of the experiments (see Figure 4). Error for the methane measurement was on average between 1.1 and 2.7 μmol and for hydrogen measurements 0.1 and 1.4 μmol in all incubations.