Rising carbon dioxide in the atmosphere and the consequent changes created through ocean acidification will cause severe ecosystem effects, impacting reef-forming habitats and the associated fish, according to new research.
Using submerged natural CO2 seeps off the Japanese Island of Shikine, an international team of marine biologists showed that even slightly higher CO2 concentrations than those existing today may cause profound changes in marine habitats and the fish that rely on them.
Writing in Science of The Total Environment, researchers from the Universities of Palermo (Italy), Tsukuba (Japan) and Plymouth showed that under elevated dissolved CO2 conditions, habitats are dominated by few ephemeral algae.
In such conditions, species such as complex corals and canopy-forming macroalgae mostly disappeared. This shift from complex reefs to habitats dominated by opportunistic low-profile algae led to a 45% decrease of fish diversity, with a loss of coral-associated species and a rearrangement of feeding behaviour.
Read more at University Of Plymouth
Image: A boxfish swimming above dense mats of diatoms in the high CO2 site along the Shikine volcanic gradient. Credit Nicolas Floc’h