Excessive rates of carbon dioxide affect the health of key micro-organisms in the oceans, potentially undermining the base of critical marine food chains, according to new research by US scientists.

A team of researchers from the Scripps Institution of Oceanography and the J. Craig Venter Institute (JCVI) applied techniques from the emerging field of synthetic biology to understand how ocean acidification from the absorption of CO2 is affecting tiny plants known as phytoplankton.

Phytoplankton like these diatoms turn out to be sensitive to ocean acidification, according to new research. Credit:Scripps Institution/Nature

Phytoplankton are not only a key food source for global fisheries, they are also important to the removal of CO2, much like how trees absorb the greenhouse gas from the atmosphere.

In a paper published on Thursday in Nature, the team demonstrated how the microscopic plants require carbonate ions to acquire iron from the water to grow.