Table 2. Comparisons of the δ15N of materials associated with native and palm forests. Differences in zooplankton δ15N were evaluated using paired comparisons (pooled by date; indicated with *) owing to their rapid turnover. All other parameters were compared using unpaired tests. Na represents the total number of measurements conducted. Nb (zooplankton only) denotes the number of temporal comparisons conducted. Sampling was evenly split between native and palm forest sites.
| Native forests Mean (± SE) | Palm forests Mean (± SE) | t (df) | P | Na; Nb | |
|---|---|---|---|---|---|
| Soils | 16.6 (± 0.9) | 10.4 (± 1.1) | 4.4 (16) | <0.001 | 18 |
| Tree leaves (T. argentea) | 15.4 (± 1.3) | 8.3 (± 2.3) | 2.6 (12) | 0.01 | 14 |
| Intertidal clams (Macoma dispar) | 11.0 (± 0.9) | 5.9 (± 0.6) | 4.6 (11) | 0.01 | 13 |
| Subtidal sponges (Spirastrella sp.) | 11.0 (± 0.1) | 10.4 (± 0.2) | 2.4 (31) | 0.02 | 46 |
| Zooplankton* | 11.3 (± 0.2) | 10.9 (± 0.2) | 3.0 (5) | 0.03 | 46; 6 |