Table 1. Summary of nanoSIMS analysis for the UCYN-A–haptophyte association from nutrient incubation experiments conducted on surface seawater samples collected from Cape Verde in May 2009.
| Experiment (treatment) | Na |
CO2
fixation or C transfer rate (fmol C cell–1 h–1) Mean±s.d. |
N2
fixation or N transfer rate (fmol N cell–1 h–1) Mean±s.d. |
||
|---|---|---|---|---|---|
| UCYN-A | Haptophyte | UCYN-A | Haptophyte | ||
| Ctr | 8 | 0.06±0.01 | 0.32±0.04b | 0.0031±0.0005 | 0.0158±0.0024 |
| N | 8 | 0.09±0.02 | 0.56±0.07b | 0.0020±0.0007 | 0.0127±0.0034 |
| Fe | 5 | 0.15±0.03b | 0.51±0.05b | 0.0072±0.0014b | 0.0326±0.0034b |
| NP | 5 | 0.19±0.04b | 0.84±0.09b | 0.0062±0.0017 | 0.0323±0.0089 |
| NFe | 4 | 0.09±0.03 | 0.69±0.16b | 0.0041±0.0014 | 0.0264±0.0088 |
| NPFe | 5 | 0.16±0.02b | 0.68±0.05b | 0.0044±0.0008 | 0.0231±0.0018 |
| Pfe | 1 | 0.16c | 0.89c | 0.0115c | 0.0789c |
| DI | 4 | 0.11±0.04 | 0.62±0.02b | 0.0069±0.0021b | 0.0475±0.0023b |
| DII | 4 | 0.13±0.04 | 0.45±0.10 | 0.0134±0.0042b | 0.0580±0.0144b |
Abbreviations: Ctr, controls; nanoSIMS, nanometer scale secondary ion mass spectrometry.
The mean and s.d. are listed for CO2 and N2 fixation and transfer rates for individual UCYN-A and partner haptophyte cells.
a
Number of cells measured in each treatment.
b
Significantly different from control measurements.
c
Based on one UCYN-A–haptophyte symbiosis.