TABLE 2.
Maximum endogenous formation rates of methane and MT determined from slurries prepared from various sediments and incubated under different conditions
| Sediment origin | Rate of formation of:
|
CH4 from MTa (%) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| CH4 (nmol/ml of sediment slurry/h) after addition ofb:
|
MT (pmol/ml of sediment slurry/h) after addition ofb:
|
||||||||
| Nothing (control) | BES | BES + tungstate | BES + syringate | Nothing (control) | BES | BES + tungstate | BES + syringate | ||
| Zegveld I | 19.1 | 4.5 | 4.1 | 4.4 | 1.0 | 19.9 | 24 | 80.1 | 0.11 |
| Zegveld II | 27.5 | 2.8 | 2.8 | 2.0 | 1.8 | 46.3 | 52.4 | 57.1 | 0.15 |
| Hatertse Vennen | 9.1 | 1.0 | 0.5 | 0.5 | <1.0 | 11.5 | 11.2 | 14.5 | 0.11 |
| Bruuk I | 54.4 | 3.2 | 2.9 | 2.9 | <1.0 | 13.7 | 14.7 | 17.9 | 0.02 |
| Bruuk II | 27.2 | 2.3 | 1.6 | 1.6 | 4.7 | 38.1 | 33.1 | 53.9 | 0.10 |
| Dekkerswald | 84.9 | 4.0 | 3.2 | 4.1 | <1.0 | 306 | 328 | 315 | 0.30 |
| Breukelen | 13.0 | 3.1 | 2.9 | 3.1 | <1.0 | 44.3 | 51.7 | 181 | 0.38 |
| Tienhoven I | 7.5 | 0.2 | 0.1 | 0.1 | <1.0 | 7.1 | 7.7 | 8.2 | 0.08 |
| Tienhoven II | 9.1 | 0.6 | 0.5 | 0.5 | <1.0 | 12.8 | 16.1 | 16.2 | 0.14 |
| Maarssen | 12.7 | 0.6 | 0.6 | 0.3 | <1.0 | 35.3 | 31.1 | 28.5 | 0.22 |
a
The percentage was calculated from known stoichiometry using the amounts of MT formed in the presence of BES and CH4 produced (control values minus BES values).
b
BES (2.5 mM) was used to inhibit methanogenesis, and tungstate (2 mM) was used to inhibit sulfate-reducing bacteria.