Profiling coral reef productivity and calcification using pH and oxygen electrodes

An instrument package carrying pH and oxygen electrodes and a thermister was floated across a reef flat. Using equations associated with the alkalinity anomaly technique, and by making certain assumptions, the productivity and calcification rates of the reef flat were calculated. At an average light intensity of 800 μE · m^?2 · s^?1, the average net oxygen production was 21.5 mmol O₂ · m^?2 · h^?1 and the average rate of calcification was 11.0 mmol CaCO₃ · m^?2 · h^?1. Results showed three metabolic zones within the transect which corresponded to zonation seen in an aerial photograph and confirmed by benthic surveys.