Table 2. Photosynthetic performance of two filmy ferns with contrasting vertical distribution on tree trunks: Hymenoglossum cruentum and Hymenophyllum dentatum.
Parameters were obtained from gas exchange measurements: Rd, dark respiration; Amax, maximum CO2 assimilation rate; Ic, light compensation point; Is, light saturation point. Data are shown as mean values ± SE (n = 6).
| H. cruentum | H. dentatum | |
|---|---|---|
| Rd (μmol CO2 m-2 s-1) | 0.02 ± 0.01 | 0.08 ± 0.01*** |
| Amax (μmol CO2 m-2 s-1) | 1.16 ± 0.02 | 0.54 ± 0.01*** |
| Ic (μmol photons m-2 s-1) | 1.45 ± 0.07 | 4.9 ± 0.15*** |
| Is (μmol photons m-2 s-1) | 24.6 ± 0.07 | 40.5 ± 1.4** |
Levels of significance:
**, P <0.001;
***, P <0.0001.