Table 1.
Origin and characteristics of the sediment used for sediment–water slurry incubations
| Sampling site | Water depth (m) | Sediment sample (cm) | Median grain size (μm) | Percentage of silt (<63 μm) | TOC content (%) | δ13C-OM | δ13C-Carbonate |
|---|---|---|---|---|---|---|---|
| Skagerrak 57°50 N, 10°01 E | Subtidal 59 m | Subtidal 0–2 | 41.2 (0.7) | 69.4 (0.5) | 0.86 (0.02) | −22 (−19) | +0.5 (0.0) |
| Subtidal 18–20 | 45.8 (0.2) | 65.5 (0.1) | 0.79 (0.01) | −22 (−19) | +0.6 (0.1) | ||
| Scheldt estuary 51°26 N, 3°57 E | Intertidal low tide | Intertidal 0–2 | 109 (0.8) | 19.4 (0.1) | 0.24 (0.10) | −19 (−16) | −0.17 (0.1) |
Average median grain size (μm), average percentage of silt (fraction smaller than 63 μm), average total organic carbon content (percentage of TOC; n = 2 and standard errors in brackets)
Also given is the measured stable carbon isotope signature (‰) of bulk sediment organic matter (OM) with in brackets the value of “reactive” OM (that of bacteria PLFA, see “Materials and methods”)
In the last column, measured δ13C of sediment bulk carbonate (SE)