Our directory of things of interest

University Directory

Follow that phytoplankton: modelling the Antarctic

The journey to the seafloor can indicate where there might be life. Creatures such as sea squirts are ‘suspension feeders’, and with sacs that look like blown glass, they catch phytoplankton as it passes The journey to the seafloor can indicate where there might be life. Creatures such as sea squirts are ‘suspension feeders’, and with sacs that look like blown glass, they catch phytoplankton as it passes Jonny Stark
10 Feb
The biodiversity of the Antarctic seafloor has been modelled for the first time

Relatively little is known about life on the Antarctic seafloor. A combination of deep water, ice and inaccessibility means that the type and abundance of creatures living there have been almost impossible to guess – until now.

By crossing the movements of ocean currents with satellite images of phytoplankton, Jan Jansen, a PhD student at Institute for Marine and Antarctic Studies, has been able to create breakthrough predictions of life beneath the cold surface.

Why phytoplankton? ‘For most animals on the seafloor, food originating at the ocean surface is their only source,’ says Jansen. Light cannot reach depths below 200 metres, and no light means no photosynthesis, which in turn means no plants. Therefore, the whereabouts of life-giving phytoplankton can largely dictate the biodiversity on the seafloor. Luckily, it can be seen in swarms on the ocean surface from satellites.

‘That’s where it gets tricky,’ says Jansen, ‘because phytoplankton rarely lands directly on the bottom of where it began on the surface. It is shifted around by open water currents first, and then by currents close to the seafloor before it settles.’

Satellite data needed to be collated with maps of the ocean currents. This was then compared to the amount of phytoplankton collected in seafloor core samples. Curiously, Jansen found that the phytoplankton moved around most when in deep currents near the seafloor. ‘The strength and speed of these deep currents was by far the most important factor determining where the phytoplankton settled.’

The ability to predict biodiversity is especially useful for a region that is difficult for scientists to access. While the study was confined to eastern Antarctica, scientists hope the method could be used to generate maps of biodiversity all around the continent. 

This was published in the February 2018 edition of Geographical magazine.

red line


Geographical Week

Get the best of Geographical delivered straight to your inbox by signing up to our free weekly newsletter!

red line

Related items

Geographical Week

Get the best of Geographical delivered straight to your inbox every Friday.

Subscribe to Geographical!

Adventure Canada


Aberystwyth University University of Greenwich The University of Winchester




Travel the Unknown


Like longer reads? Try our in-depth dossiers that provide a comprehensive view of each topic

  • National Clean Air Day
    For National Clean Air Day, Geographical brings together stories about air pollution and the kind of solutions needed to tackle it ...
    The Air That We Breathe
    Cities the world over are struggling to improve air quality as scandals surrounding diesel car emissions come to light and the huge health costs of po...
    Diabetes: The World at Risk
    Diabetes is often thought of as a ‘western’ problem, one linked to the developed world’s overindulgence in fatty foods and chronic lack of physi...
    When the wind blows
    With 1,200 wind turbines due to be built in the UK this year, Mark Rowe explores the continuing controversy surrounding wind power and discusses the e...
    The true cost of meat
    As one of the world’s biggest methane emitters, the meat industry has a lot more to concern itself with than merely dietary issues ...


NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...


It takes a lot more than the latest research data…


NGOs shine a light on the underreporting of wildlife crime…


Pioneering laser photography is being used by scientists on the…


Annual competition looks to celebrate island life in all its…


Increasing interest in offshore aquaculture is dividing environmentalists


Well-meaning promises don’t always have positive outcomes. Marco Magrini finds…


The RSPB introduces a new hotline for reporting the unlawful…


With the death earlier this week of the world’s last…


The essence of street photography is its raw, unfiltered, unstaged…


For Marco Magrini, a tax on fossil fuels would be…


Half of animal species in world’s most biodiverse areas could…


Four-year project to reestablish safe breeding grounds for seabirds on…


First global atlas of soil bacteria reveals a small minority…


Scientists discover how shrubs are dominating the Arctic tundra


War and conservation have a complicated relationship, with two studies…


Why is Europe so cold right now? Marco Magrini suggests…


Threatened Californian owls are suffering from digesting rat poison administered…


With the majority of the ocean still remaining undiscovered, a…


Belize bans offshore oil extraction to protect the second longest…


With their horns still much-prized by poachers, will the revered…