Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coccolithophore blooms in the southwest Atlantic

22.10.2010
A study led by Dr Stuart Painter of the National Oceanography Centre helps explain the formation of huge phytoplankton blooms off the southeast coast of South America during the austral summer (December-January). The region supports the highly productive Patagonian Shelf marine ecosystem, which includes a globally important fishery.

Coccolithophores are key members of the marine phytoplankton community. They are abundant in the sunlit upper layer of the world’s oceans, often forming vast blooms that can be seen from space.

“Coccolithophores are a complex group of plankton and in many areas of the World Ocean satellite-based observations provide the only information we have. We often have little direct knowledge of the environmental factors coincident with these blooms,” explained Painter.

To understand the environmental factors controlling the development of coccolithophore blooms, Painter and his coauthors joined a cruise led by Dr William Balch of the Bigelow Laboratory (Maine, USA) and measured the salinity, chemistry and nutrient levels of the waters overlying the Patagonian Shelfand the shelf break, where the seafloor dips down to the deep seabed.

They also took measurements at the Brazil/Falklands Confluence to the northeast, where two major currents collide. These are the Brazil Current, which carries warm, saline subtropical waters southwards, and the Falklands Current, which brings cold, fresh and nutrient-rich water up from the sub-Antarctic region.

The continental shelf itself experiences strong tides and inputs from large rivers. And to complicate matters further, low-salinity water also enters the Patagonian Shelf region from the Pacific Ocean through the Magellan Strait in the south.

“The marine environment of the Patagonian Shelf region is well known for its complexity but what has been less clear until now is how this relates to the large blooms of coccolithophores in this region,” said Painter.

He and his collaborators identified five distinct water masses, each having different characteristics, such as temperature and nutrient concentration. These water masses also varied in the amount of chlorophyll in their surface waters, indicating different levels of phytoplankton production.

During the research cruise, a large bloom of the globally ubiquitous coccolthophore species Emiliania huxleyiformed in the sub-Antarctic Shelf Water (SSW), north of the Falkland Islands. The bloom extended north along the shelf break and coincided with the distribution of reflective calcite detected from space, which was otherwise diffusely distributed. Calcite is a carbonate mineral and a common constituent of limestone. It also forms the microscopic plates – ‘coccoliths’ – that surround coccolithophores, possibly for protection.

Chemical and nutrient measurements confirmed that conditions within the SSW were especially conducive for coccolithophore bloom formation, with the right cocktail of nutrients and seawater temperature.

However, the distribution of the SSW is strongly influenced by the shelf break front, which is the focus of intense biological production. It can vary from 20 to 200 kilometres in width determining exactly where conditions are right for coccolithophore blooms.

“The complex interaction of large currents and different water masses clearly exerts strong controls over the position of coccolithophore blooms in this region,”said Painter.

The research was carried out 2008, during the period of peak coccolithophore abundance (December), while aboard the America research vessel Roger Revelle. Remote sensing data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument the Aqua satellite was acquired from NASA.

The researchers were Stuart Painter, Alex Poulton and John Allen of the National Oceanography Centre, Rosalind Pidcock of the University of Southampton’s School of Ocean and Earth Science, and William Balch of the Bigelow Laboratory for Ocean Sciences, Maine, USA.

The Coccolithophores of the Patagonian Shelf (COPAS) research cruise was funded by the US National Science Foundation. Further financial support was provided by the US Defence Science and Technology Laboratory and the Natural Environment Research Council.

Publication:
Publication: Painter, S. C., Poulton, A. H., Allen, J. T., Pidcock, R. & Balch, W. M. The COPAS’08 expedition to the Patagonian Shelf: Physical and environmental conditions during the 2008 coccolithophore bloom. Continental Shelf Research (published online, 2010). doi:10.1016/j.csr.2010.08.013

Dr. Rory Howlett | EurekAlert!
Further information:
http://www.soton.ac.uk
http://noc.ac.uk/news/coccolithophore-blooms-southwest-atlantic

More articles from Ecology, The Environment and Conservation:

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>