News: A study of a microscopic ancient marine algae (Coccolithophores) has found that there is a decrease in the concentration of oceanic calcium carbonate (CaCO3) in the southern Indian ocean.
- Coccolithophores: They are single-celled algae living in the upper layers of the world’s oceans.
- They play a key role in marine ecosystems as they calcify marine phytoplankton that produce upto 40% of ocean calcium carbonate and are responsible for 20% of the global net marine primary productivity.
- They also play an important role in the carbon cycle because they remove CO2 from the atmosphere.
- Threats: The coccolithophores are reducing due to an increase in the presence of diatom algae which occurs after sea ice breakdown with climate change and ocean acidification and increases the silicate concentration in the waters of the Southern Ocean.