New Research Reveals Diatoms' Surprising Carbon Accumulation Methods

New research suggests that diatoms, a type of microscopic algae living in the ocean, have multiple methods of accumulating carbon. Aside from relying on photosynthesis, these single-celled plankton also increase their biomass by directly consuming organic carbon from the ocean. This discovery has the potential to revise scientists' estimates of how much carbon dioxide diatoms absorb from the atmosphere through photosynthesis. Consequently, our understanding of the global carbon cycle, especially in the context of climate change, may undergo significant changes.

The University of California, San Diego, led the study, which involved bioengineers, bioinformatics experts, and genomics researchers. The recent findings were published in the scientific journal Science Advances.

The researchers focused on a specific algae species called Cylindrotheca closterium, which is widely distributed in oceans worldwide. They discovered that this algae species often engages in a process known as mixotrophy, which involves a combination of photosynthesis and heterotrophic intake of organic carbon from sources like plankton. In over 70% of the water samples analyzed from oceans around the globe, Cylindrotheca closterium exhibited signs of both photosynthesis and direct consumption of organic carbon. Additionally, this diatom can grow at an accelerated rate when consuming organic carbon. The preliminary findings of the study also suggest the intriguing possibility that certain bacteria species directly supply organic carbon to the majority of diatoms inhabiting the world's oceans.