Written By: Kylie-Anne Grube
A segment highlighting the unique, intricate, and surprising complexities of our natural systems.
One out of every five breaths you take are brought to you by a perhaps surprising source: diatoms. These teeny tiny single-celled algae live throughout the world’s oceans, lakes, rivers, and ponds; however, diatoms can thrive wherever light, carbon dioxide, moisture, and nutrients exist! Harnessing energy from the sun, diatoms turn carbon into a sugar fuel, and, in the process, release 20% of the world’s oxygen into the atmosphere. From oxygen production, carbon storage, controlling marine ecosystem productivity, to both making and fertilizing the Earth, the life cycle of diatoms form one of the most important biological processes on the planet!
Diatoms form the foundation of the marine food-chain
Diatoms, along with other members of the phytoplankton community bloom in large numbers, particularly in the spring and summer, providing an essential food source for our waters. Zooplankton, aquatic insects, fish, and even whales depend on diatoms – without them, places such as the Arctic Ocean, where diatoms are the greatest contributor to primary production, would lose much of its biodiversity.

Credit: NASA Earth Observatory
They help us understand our climate
Diatoms are extremely sensitive to climactic changes and this means they can tell us a lot about environment over time. As diatoms die, they become fossils in the sedimentary rock record. When studied by scientists, called paleolimnologists, diatoms provide a plethora of information about past temperatures, pH levels, and carbon concentrations. So far, we have diatoms dating back to 185 million years ago – now that’s a lot of data!

Diatoms help us breathe and store away that pesky CO2
Throughout their lives diatoms produce 20% of the world’s oxygen and store 40% of atmospheric carbon dioxide. At the end of their life, they deposit this carbon as sediment, storing it away for up to 100 years.

Despite being smaller than a millimetre each, diatoms are well travelled micro-organisms
Diatoms use silica to build transparent cell walls with beautiful and intricate patterns. In fact, they are the only organism on Earth to construct their cell walls with this transparent, opaline silica. At the end of their life, the diatom dies, but their silica walls, often referred to as shells, remain intact. These shells pile up over thousands and thousands of years, transforming aquatic landscapes into deserts and the nutrient rich sediment they create becomes the fertilizer of new life.
Take the Sahara desert for instance. 7000 years ago, this land mass was actually made up of large lakes filled with – you guessed it – diatoms. When the lakes began to dissipate, they left behind diatom rich desert sand. During the winter, winds from the mountains of Saharan Africa sweep this dust high into the sky, forming a diatom procession that travels across the Atlantic Ocean before finally reaching the moisture laden air of the Amazon Basin. Here, the vapour condenses onto the dust particles, forming a mineral rich diatom rain that pours upon the forest. In alignment with the seasonal wind patterns of Saharan African, annual floods in Amazon wash the previous year’s fertilizer from the soil and carry it back to various water bodies, where it provides food for new diatoms to bloom. And so the cycle continues.
_________________________________________________________________________
These tiny little algae cells play an integral role in the flourishing of life all around the globe. The diatom is a symbol of the unimaginable and complex processes required to sustain our planet and an important reminder of our responsibility to preserve the balance of these delicate natural cycles. Pretty neat, huh?
