From the tropics to the eternal ice: Research expeditions to study the microalgae that make life in the ocean possible

Georg Pohnert

Institute for Inorganic and Analytical Chemistry, FSU Jena

Phytoplankton—tiny algae that float freely in the sea—form the invisible basis of life in the ocean. Through photosynthesis, they use sunlight to generate energy, thereby supplying the entire marine food web. In doing so, they produce almost as much oxygen as all land plants combined.
Despite their enormous importance, we still know surprisingly little about these microalgae. To study them, we have to go where they live – in the middle of the ocean. This often means undertaking costly expeditions with research vessels or mobile stations to remote and extreme regions of the world's oceans.
In this lecture, we take you on a scientific journey: aboard the Tara Polar Station, drifting through the Arctic sea ice, we investigate how microorganisms survive the months of darkness of the polar night. In the Amazon delta, we search for chemical traces of microalgae that migrate from freshwater to the sea.
Our research combines data from very different habitats on Earth – from tropical seas to eternal ice – to better understand how microalgae make life in the oceans possible.