Oceans' microscopic plants—diatoms—capture carbon dioxide via biophysical pathways

Diatoms are tiny unicellular plants—no bigger than half a millimeter—which inhabit the surface water of the world's oceans where sunlight penetration is plenty. Despite their modest size, they are one of the world's most powerful resources for removing carbon dioxide (CO2) from the atmosphere. They currently remove, or "fix," 10-20 billion metric tons of CO2 every year by the process of photosynthesis. But not much is known about which biological mechanisms diatoms use, and whether these processes might become less effective with rising ocean acidity, temperatures, and, in particular, CO2 concentrations. A new study in Frontiers in Plant Science shows that diatoms predominantly use one pathway to concentrate CO2 at the vicinity of carbon fixing enzyme and that this continues to operate even at higher CO2 concentrations.