Effects of ocean acidification on microbial community composition of, and oxygen fluxes through, biofilms from the Great Barrier Reef

Ocean acidification triggers rapid shifts in microbial communities within biofilms of the Great Barrier Reef, with specific bacterial groups showing sensitivity to increased CO₂ levels. Research found that elevated pCO₂ (560–1140 ppm) reduced Alphaproteobacteria while increasing Flavobacteriales, indicating a pH-driven reorganization. Despite these changes, oxygen production in biofilms remained stable, suggesting adaptability in microbial activity. The study exposed natural biofilms to controlled CO₂ scenarios—pre-industrial, present-day, mid-century, and late-century levels—and analyzed bacterial composition using molecular techniques. Findings highlight the resilience of biofilm ecosystems but underscore potential long-term impacts on reef health.

Witt, V., Wild, C., Anthony, K. R. N., Diaz‐Pulido, G., & Uthicke, S. (2011). Effects of ocean acidification on microbial community composition of, and oxygen fluxes through, biofilms from the Great Barrier Reef. Environmental Microbiology, 13(11), 2976–2989. Portico. https://doi.org/10.1111/j.1462-2920.2011.02571.x