TABLE 3.
Comparison of virus counts and virus-to-bacterium ratios in sediments from different locations
| Study area | Depth (m) | Total virus no. (109 viruses g−1) | Virus-to-bacterium ratio | Methodd | Reference |
|---|---|---|---|---|---|
| Freshwater sediments | |||||
| Lake Gilbert (Canada) | 2-14 | 0.65-2.90 (1.53)a,b | 1-4 | TEM | 19 |
| Mahoning River (Ohio) | <1 | 0.67 | 0.7-1.2 | YO-PRO | 18 |
| Marine sediments | |||||
| Key Largo (Florida) | 1-10 | 0.13-0.50 (0.4)a | NDc | TEM | 22 |
| Bering Sea | ND | 0.027a | 12.8 | TEM | 25 |
| Chesapeake Bay | ND | 0.22-0.44 (0.36)a | 30.1-71.0 | YO-PRO | 11 |
| Sporades (eastern Mediterranean) | 1,232 | 1.22-3.22 (2.38) | 1.7-2.7 | SYBR-TEM | 7 |
| Cretan Sea (eastern Mediterranean) | 1,840 | 2.03 (2.02) | 5.2-5.7 | SYBR-TEM | 7 |
| Ierapetra Trench (eastern Mediterranean) | 4,235 | 0.51-1.51 (1.21) | 1.9-3.7 | SYBR-TEM | 7 |
| Porcupine Abyssal Plain (northeast Atlantic Ocean) | 4,800 | 10.05-11.71 (11.12) | ND | SYBR | 8 |
| Falconara (Adriatic Sea) | 0.5 | 1.08-1.20 (1.13) | ND | SYBR-TEM | 8 |
| Deep Mediterranean (western stations) | 1,290-4,000 | 0.05-0.12 (0.08) | 0.11-0.47 (0.24) | SYBR | This study |
| Deep Mediterranean (eastern stations) | 2,100-3,870 | 0.04-0.08 (0.06) | 0.11-0.19 (0.13) | SYBR | This study |
a
Number of viruses per milliliter of sediment. The values in parentheses are averages.
b
The value obtained at a depth of 4 m was not included.
c
ND, not determined.
d
TEM, transmission electron microscopy; YO-PRO, YO-PRO fluorochrome stain; SYBR, SYBR Green I fluorochrome stain.