2025 Volume 27 Issue 1 Pages 47-61
We collected bubbles from the seafloor of coral reef areas to determine their quantity and chemical composition. The chemical composition was high in oxygen and low in carbon dioxide compared to that of the atmosphere. Oxygen fluxes to the atmosphere from coral reef waters are generally determined considering only dissolved oxygen in seawater, but accounting for bubbled oxygen increased such fluxes by about 70%. At the same time, the primary production rate in coral reefs is estimated only from the dissolved oxygen concentration in seawater, but accounting for bubbled oxygen increased it by about 20–30%. The composition of bubbled gases suggests that approximately 20% of the oxygen present may be derived from photosynthesis in the reef area. Global quantitative estimation of bubbled oxygen fluxes in tropical and subtropical coral reef waters remains critical for future research.