Table 1. Sampling site descriptions.
| Study sites | Coordinates | Sampling date | Sampling device | Water depth (m) | Average environmental temperature (°C) | Salinity (‰) | Wet density (g/cm3) | Porosity | C/N | TOC (%) | Sediment description |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Southern Ocean (Weddell Sea) | 65° 26′ S 61° 26′ W | Sep-07 | Multi core | 850 | 0a | 34a | 1.5 | 0.7 | 7 | 0.3 | Permanently cold sediment situated near a methane-venting cold seep, consisting of light-gray stiff clay |
| Arctic Ocean (Ymerbukta, Svalbard) | 78° 16′ N 14° 02′ E | Jul-05 | Push core | Subtidal | 0a | 27–30a | 1.5 | 0.6 | 13 | 2.9 | Seasonally freezing-thawing sediment located at the tidal-dominated fringe of a glacier moraine and consisting of black coarse-grained sand |
| Arctic Ocean (Smeerenburgfjord, Svalbard) | 79° 42′ N 11° 05′ E | Aug-07 | HAPS core | 215 | 0a | 33-34a | 1.7 | 0.6 | 11 | 1.6 | Permanently cold sediment with abundant worm burrows, soft brown clay grading to mottled dark gray-black at depth |
| North Sea (Wadden Sea, German Bight) | 53° 27′ N 08° 07′ E | May-07 | Push core | Intertidal | 12b | 22–30b | 1.3 | 0.7 | 13 | 3.0 | Estuary subjected to large seasonal temperature changes with abundant meio- and macrofauna, light-brown sandy mud changing to black at depth |
| Baltic Sea (Arkona Basin) | 54° 46′ N 13° 48′ E | Jun-07 | Multi core | 9 | 8b | 8–9b | 1.2 | 0.7 | 9 | 6.1 | Sediment subjected to small seasonal temperature changes, dark-brown and black mud |
| Arabian Sea (off the coast of Goa, India) | 15° 6′ N 73° 24′ E | Apr-07 | Multi core | 60 | 26a | 34–35a | 1.2 | 0.8 | 14 | 3.0 | Permanently warm sediment from an upwelling system, green soft fine-grained and watery mud |
| Arabian Sea (Sadeyat island, United Arab Emirates) | 24° 31′ N 54° 26′ E | Sep-07 | Push core | Intertidal | 30a | 200a | 1.4 | 0.7 | 106 | 1.4 | Permanently warm hypersaline sediment covered by a 0.5-cm-thick microbial mat, fine-grained sand, yellow with gray-black streaks |
| Andaman Sea (Phuket Island, Thailand) | 08° 03′ N 98° 25′ E | Aug-07 | Push core | Intertidal | 28a | 28–34a | 1.3 | 0.6 | 30 | 3.6 | Permanently warm tide-dominated mangrove forest, brown coarse-grained sand |
| South China Sea (Hainan Island, China) | 19° 35′ N 110° 48′ E | Sep-07 | Push core | Intertidal | 30a | 15–25a | 1.8 | 0.4 | 10 | 0.2 | Permanently warm sediment with abundant worm burrows, dark-brown sand |
Abbreviation: TOC, total organic carbon.
a
In situ measurements.
b
Measurements from closest automated monitoring station.