Table 3. The effects of time of sampling (morning vs. afternoon) and treatment factors (light vs shade) on water chemistry in the laboratory experiment.
pH | DO | ALK | DIC | DOC | Si | SRP | ||||||||||
df | F | p | F | p | df | F | p | F | p | F | p | F | p | F | p | |
Irradiance | 1 | 66.2 | <0.0001 | 703 | <0.0001 | 1 | 29.7 | <0.0001 | 38.4 | <0.0001 | 0.418 | 0.5251 | 2.81 | 0.1092 | 0.056 | 0.8151 |
Time | 1 | 40.5 | <0.0001 | 162 | <0.0001 | 1 | 14.8 | 0.0010 | 16.5 | 0.0006 | 0.639 | 0.4336 | 0.477 | 0.4979 | 2.41 | 0.1360 |
Irradiance:Time | 1 | 19.2 | <0.0001 | 88.8 | <0.0001 | 1 | 2.44 | 0.1337 | 3.49 | 0.0765 | 0.009 | 0.9252 | 11.2 | 0.0033 | 0.017 | 0.8966 |
Residuals | 109 | 20 |
pH, dissolved oxygen saturation (DO, %), alkalinity (ALK, µEq/kg), concentrations of dissolved inorganic carbon (DIC, µM), dissolved organic carbon (DOC, mg L−1) silicic acid (Si, µM) and soluble reactive phosphorus (SRP, µM) in the treatment units. Results of linear mixed-effects models comparing controls only (no algal water added; treatment = light versus shade).