Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Arctic Survivalists

02.05.2018

Phytoplankton assemblages in coastal waters remain productive, despite variable environmental conditions

They form the basis of the Arctic food web – and are extremely tough: even when the water becomes more acidic and the available light or temperatures change, various phytoplankton assemblages in the Arctic demonstrate undiminished productivity and biodiversity.


Kongsfjord, Spitsbergen: Clara Hoppe (r.) & team

Photo: Alfred-Wegener-Institut/P. Versone

This was the main finding presented in a study by researchers at the Alfred Wegener Institute, which they jointly release with their Canadian colleagues advanced online in the journal Nature Climate Change. Yet the question of whether this source of food for seals, whales and commercially harvested fish species in the Arctic can ultimately cope with global climate change requires further research to answer.

Sometimes constant darkness under metre-thick ice, sometimes sunlight 24 hours a day; sometimes clear and salty seawater, sometimes murky freshwater from rivers; and all this at icy temperatures: phytoplankton living in the coastal waters of the Arctic have to cope with extreme and highly variable environmental conditions.

Though these aspects pose serious challenges, in an era characterised by global transformation they can also be advantageous – because they have helped Arctic phytoplankton adapt to variable environmental conditions in the course of their evolution.

That is one possible explanation for the fact that some phytoplankton assemblages can more successfully acclimate to global change than their counterparts from regions with more stable environmental conditions, as the first author of the study, biologist Dr Clara Hoppe from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) explains.

“We were able to demonstrate that some phytoplankton, the most important primary producers in the Arctic, are extremely robust. For instance, they demonstrate less sensitivity to ocean acidification than what we are used to seeing in assemblages from the Southern Ocean or the temperate latitudes,” says Clara Hoppe. In a range of experiments with naturally occurring phytoplankton assemblages, she varied the temperature, available light and pH value, and measured the phytoplankton’s productivity.

Our oceans are becoming more acidic because, due to the combustion of fossil fuels, more carbon dioxide is being released into the atmosphere. CO2 reacts with water to produce carbonic acid and reduces the water’s pH level, which, at the cellular level, can influence organisms’ metabolism, and with it, their productivity.

In nine out of ten experiments, the productivity remained unchanged; only in the experiment with the lowest temperature (1.8 degrees Celsius), increased acidification resulted in significantly decreased productivity; at the other temperatures tested (from 3 to 8 degrees Celsius), ocean acidification produced no measurable effects during the one to three week lasting experiments. As the authors conclude, “Phytoplankton are apparently capable of tolerating the higher proton levels that underlie sinking pH values, provided the temperature doesn’t drop below a certain threshold.”

The team attributes the general ability of phytoplankton from coastal regions to remain productive despite highly variable environmental conditions to a number of different mechanisms. Firstly, the individual phytoplankton seem capable of acclimating to a diverse range of conditions in a flexible way, as the AWI team was able to demonstrate in further laboratory experiments.

Secondly, many diatom species produce spores, which can survive for several years on the ocean floor. If the environmental conditions are advantageous for certain spores, they hatch and subsequently initiate phytoplankton blooms. As such, there is a “seed bank” which provides a high degree of inter- and intraspecific diversity, which allows those species and strain that are suited best for many combinations of environmental conditions to come up and thrive.

“Primary production in the Arctic is an essential ecosystem service, which the increasingly commercially important fishing grounds will also depend on. In our lab experiments, we were able to demonstrate that these producers are surprisingly resistant in terms of the ocean acidification levels we expect to see by the end of the century – and that’s good news!”, states AWI biologist Clara Hoppe. Nevertheless it is important to understand the limits and costs of this resistance, to which the study has made a valuable contribution. Whether the outcomes can also be used to draw conclusions regarding the complex food web in nature is something that only further research can tell us.

Original publication:
Clara J. M. Hoppe, Klara K. E. Wolf, Nina Schuback, Philippe D. Tortell and Björn Rost: Compensation of Ocean Acidification Effects in Arctic Phytoplankton Assemblages. DOI:10.1038/s41558-018-0142-9

EMBARGOED until 30 April 2018 at 1600 London time / 1100 US Eastern time / 1700 Central European Summertime

Notes for Editors:
Please observe the embargo. Printable images can be downloaded under the following link:
http://multimedia.awi.de/medien/pincollection.jspx?collectionName=%7B690a1917-37...

Your academic contact partner at the Alfred Wegener Institute is:
• Dr Clara Hoppe, currently working on Svalbard, please arrange appointments for phone calls via email: Clara.Hoppe(at)awi.de

At the AWI’s Communications and Media Relations department, Dr Folke Mehrtens (tel.: +49 471 4831-2007; e-mail: medien(at)awi.de) will be pleased to help you with any questions.

Follow the Alfred Wegener Institute on Twitter (https://twitter.com/AWI_Media) and Facebook (www.facebook.com/AlfredWegenerInstitute).

The Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) conducts research in the Arctic, Antarctic and oceans of the high and mid-latitudes. It coordinates polar research in Germany and provides major infrastructure to the international scientific community, such as the research icebreaker Polarstern and stations in the Arctic and Antarctica. The Alfred Wegener Institute is one of the 18 research centres of the Helmholtz Association, the largest scientific organisation in Germany.

Ralf Röchert | idw - Informationsdienst Wissenschaft
Further information:
http://www.awi.de/

More articles from Life Sciences:

nachricht Scientists first to develop rapid cell division in marine sponges
21.11.2019 | Florida Atlantic University

nachricht Machine learning microscope adapts lighting to improve diagnosis
21.11.2019 | Duke University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Machine learning microscope adapts lighting to improve diagnosis

Prototype microscope teaches itself the best illumination settings for diagnosing malaria

Engineers at Duke University have developed a microscope that adapts its lighting angles, colors and patterns while teaching itself the optimal...

Im Focus: Small particles, big effects: How graphene nanoparticles improve the resolution of microscopes

Conventional light microscopes cannot distinguish structures when they are separated by a distance smaller than, roughly, the wavelength of light. Superresolution microscopy, developed since the 1980s, lifts this limitation, using fluorescent moieties. Scientists at the Max Planck Institute for Polymer Research have now discovered that graphene nano-molecules can be used to improve this microscopy technique. These graphene nano-molecules offer a number of substantial advantages over the materials previously used, making superresolution microscopy even more versatile.

Microscopy is an important investigation method, in physics, biology, medicine, and many other sciences. However, it has one disadvantage: its resolution is...

Im Focus: Atoms don't like jumping rope

Nanooptical traps are a promising building block for quantum technologies. Austrian and German scientists have now removed an important obstacle to their practical use. They were able to show that a special form of mechanical vibration heats trapped particles in a very short time and knocks them out of the trap.

By controlling individual atoms, quantum properties can be investigated and made usable for technological applications. For about ten years, physicists have...

Im Focus: Images from NJIT's big bear solar observatory peel away layers of a stellar mystery

An international team of scientists, including three researchers from New Jersey Institute of Technology (NJIT), has shed new light on one of the central mysteries of solar physics: how energy from the Sun is transferred to the star's upper atmosphere, heating it to 1 million degrees Fahrenheit and higher in some regions, temperatures that are vastly hotter than the Sun's surface.

With new images from NJIT's Big Bear Solar Observatory (BBSO), the researchers have revealed in groundbreaking, granular detail what appears to be a likely...

Im Focus: New opportunities in additive manufacturing presented

Fraunhofer IFAM Dresden demonstrates manufacturing of copper components

The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM in Dresden has succeeded in using Selective Electron Beam Melting (SEBM) to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

High entropy alloys for hot turbines and tireless metal-forming presses

05.11.2019 | Event News

 
Latest News

Designer lens helps see the big picture

21.11.2019 | Interdisciplinary Research

Machine learning microscope adapts lighting to improve diagnosis

21.11.2019 | Life Sciences

Soft skin-like robots you can put in your pocket

21.11.2019 | Interdisciplinary Research

VideoLinks
Science & Research
Overview of more VideoLinks >>>