Table 1.
Rates of microbiological processes as determined by radioisotopic methods
| Gas in headspace, sample | Sample typea | Incubation temp (°C) | Mean rate (ng C cm−3 day−1)b ± SD of: |
Mean rate of sulfate reduction (μg S cm−3 day−1)b ± SD | ||
|---|---|---|---|---|---|---|
| Inorganic carbon assimilation | Lithotrophic methanogenesis | Acetate oxidationc | ||||
| N2 | ||||||
| AM-05 | F | 65 | 0 | 0 | 1.4 ± 0.3 | 0 |
| AM-06 | F | 80 | 0 | 0 | 0.87 ± 0.2 | 0 |
| AM-12 | F | 80 | 0 | 0 | 0 | 0 |
| AM-03 | F+S | 65 | 2.8 ± 0.4 | 4.5 ± 0.8 | 2.4 ± 0.5 | 0 |
| AM-03 | F+S | 80 | 10.5 ± 2.4 | 0.97 ± 0.2 | 4.9 ± 0.8 | 0 |
| AM-05 | F+S | 80 | 0.18 ± 0.03 | 0 | — | 0 |
| AM-15 | F+S | 80 | 1.4 ± 0.3 | 0 | 2.8 ± 0.5 | 0 |
| AM-15 | F+S | 90 | 1.9 ± 0.2 | 0.16 ± 0.03 | 1.5 ± 0.3 | 0 |
| AM-15 | F+S | 100 | 2.0 ± 0.2 | 1.4 ± 0.2 | 1.2 ± 0.2 | 0 |
| AM-16 | F+A | 80 | 0.30 ± 0.05 | 0.09 ± 0.02 | 35.0 ± 6 | 0 |
| AM-17 | F+A | 80 | 5.4 ± 1.0 | 0.11 ± 0.02 | 25.0 ± 5 | 0 |
| H2 | ||||||
| AM-03 | F+S | 65 | — | 13.1 ± 2 | — | 250 ± 45 |
| AM-03 | F+S | 80 | 1.0 ± 0.2 | 22.1 ± 4 | — | 0 |
| AM-05 | F+S | 80 | 0.12 ± 0.02 | 22.6 ± 4.5 | — | 135 ± 30 |
| AM-06 | F | 80 | 0 | 0 | — | 0 |
| AM-16 | F+A | 80 | 1.7 ± 0.3 | 3.1 ± 0.6 | — | 200 ± 30 |
| AM-17 | F+A | 80 | 0.24 ± 0.05 | 0.8 ± 0.2 | — | 0 |
a
F, fluid; S, sulfidic structure; A, sheaths of Alvinella.
b
0, background level; —, not determined.
c
Potential rate of acetate transformation.