Table 1.
Description of the location and oceanographic properties of sampling sites
| Peak-1 | Declining-1b | Declining-2 | Peak-2b | Sea iceb | |
|---|---|---|---|---|---|
| Sampling date | 2010/2011 cruise; 07 Jan 2011 | 2011/2012 cruise; 14 Feb 2012 | 2011/2012 cruise; 29 Feb 2012 | 2013/2014 cruise; 03 Jan 2014 | 2010/2011 cruise; 05 Jan 2011 |
| Sampling pointa (depth) | Polynya (30 m) | Polynya (20 m) | Polynya (25 m) | Polynya (20 m) | Under sea ice (2 m) |
| Abundance of bacteria (×106 16S rRNA gene copies/mL) | 2 | 25 | 9.7 | 7.2 | 1.4 |
| NO2- + NO3- (μmol/L) | 15.0 | 9.6 | 16.6 | 14.9 | 26.6 |
| NH4+ (μmol/L) | 0.5 | 0.3 | 0.6 | 0.03 | 1.6 |
| PO42- (μmol/L) | N/D | 1.0 | 1.4 | 1.4 | N/D |
| SiO2 (μmol/L) | 79.4 | 74.7 | 77.4 | 84.8 | 76.7 |
| Chl-a (mg/L) | 9.5 | 5.9 | 2.4 | 5.8 | 1.0 |
| Phytoplankton composition (μg C/L) | |||||
| Phaeocystis antarctica | 279.8 | 174.0 | 38.5 | 255.3 | 6.0 |
| Autotrophic picoplankton | 2.4 | 10.0 | 1.7 | 0.02 | 3.7 |
| Autotrophic flagellates | 6.7 | 2.8 | 4.4 | 3.6 | 0.9 |
| Diatom | 83.0 | 16.6 | 15.6 | 7.9 | 67.0 |
| Total carbon (μg C/L) | 367.6 | 203.3 | 60.1 | 266.8 | 77.6 |
| Carbon to Chl-a | 38.69 | 34.6 | 25.09 | 46 | 81.7 |
aGPS position: polynya center station, 73.30 (LAT) -113.02 (LONG); sea ice station 72.30 (LAT), -112.44 (LONG)
bUsed for metagenomics and metatranscriptomic analyses