Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists discover new reef system at mouth of Amazon River

25.04.2016

A new reef system has been found at the mouth of the Amazon River, the largest river by discharge of water in the world. As large rivers empty into the world's oceans in areas known as plumes, they typically create gaps in the reef distribution along the tropical shelves--something that makes finding a reef in the Amazon plume an unexpected discovery.

An international team--including scientists from the University of Georgia and the Federal University of Rio de Janeiro--documented their findings in an April 22 study published in the journal Science Advances.


The Amazon River meets the Atlantic Ocean and creates a plume where freshwater and salt water mix. The plume affects a broad area of the tropical North Atlantic Ocean in terms of salinity, pH, light penetration and sedimentation, conditions that usually correlate to a major gap in Western Atlantic reefs.

Credit: Lance Willis

Scientists on a recent expedition to investigate the Amazon River plume included a Brazilian research team looking for evidence of a reef system along the continental shelf.

The Amazon plume--an area where freshwater from the river mixes with the salty Atlantic Ocean--affects a broad area of the tropical North Atlantic Ocean in terms of salinity, pH, light penetration and sedimentation, conditions that usually correlate to a major gap in Western Atlantic reefs.

Carlos Rezende from the State University of North Fluminense, Fabiano Thompson from the Federal University of Rio de Janeiro and Rodrigo Moura, a reef ecologist from UFRJ who has written extensively about richness of reef corals south of the Amazon River mouth, led the reef discovery team.

"Our expedition into the Brazil Exclusive Economic Zone was primarily focused on sampling the mouth of the Amazon," said Patricia Yager, an associate professor of marine sciences in UGA's Franklin College of Arts and Sciences and principal investigator of the River-Ocean Continuum of the Amazon project.

"But Dr. Moura had an article from the 1970s that mentioned catching reef fish along the continental shelf and said he wanted to try to locate these reefs."

The difficulty of finding the old map coordinates with modern GPS notwithstanding, the team used multibeam acoustic sampling of the ocean bottom to find the reef and then dredged up samples to confirm the discovery.

"We brought up the most amazing and colorful animals I had ever seen on an expedition," Yager said.

The Brazilian researchers then organized a full team and took a Brazilian Navy research vessel back to the site in 2014, when they were able to collect and fully describe the findings for the study.

The Amazon River plume and its effects on the global carbon budget converged with the discovery of the reef system to provide scientists a wider view of the reef community, its variation and changes. Microorganisms thriving in the dark waters beneath the river plume may provide the trophic connection between the river and the reef.

"The paper is not just about the reef itself, but about how the reef community changes as you travel north along the shelf break, in response to how much light it gets seasonally by the movement of the plume," said Yager, who spent two months in Brazil as a Science Without Borders visiting professor.

"In the far south, it gets more light exposure, so many of the animals are more typical reef corals and things that photosynthesize for food. But as you move north, many of those become less abundant, and the reef transitions to sponges and other reef builders that are likely growing on the food that the river plume delivers. So the two systems are intricately linked."

But the reefs may already be threatened.

"From ocean acidification and ocean warming to plans for offshore oil exploration right on top of these new discoveries, the whole system is at risk from human impacts," she said.

###

The research is supported by grants from the National Science Foundation and the Gordon and Betty Moore Foundation, as well as support from Brazilian agencies and foundations including CNPq, the Brazilian National Council for Scientific and Technological Development; CAPES, a foundation for the Coordination for the Improvement of Higher Education Personnel; FAPERJ, the research support foundation of the State of Rio de Janeiro; FAPESP, the São Paulo Research Foundation; Brasoil; MCTI, the Brazilian Ministry of Science, Technology and Innovation; and the Brazilian Navy.

The study, "An extensive reef system at the Amazon River mouth," is available at http://advances.sciencemag.org/content/advances/2/4/e1501252.full.

Media Contact

Stephanie Schupska
schupska@uga.edu
706-542-6927

 @universityofga

http://www.uga.edu 

Stephanie Schupska | EurekAlert!

Further reports about: Amazon Atlantic continental shelf marine sciences reef corals

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>