Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ocean Warming May Increase the Abundance of Marine Consumers

26.08.2009
Warmer ocean temperatures could mean dramatic shifts in the structure of underwater food webs and the abundance of marine life, according to a new study by researchers at the University of North Carolina at Chapel Hill.

Until now, little has been known about how changes in temperatures might affect the total productivity and growth of all marine consumers (such as animals, fungi and bacteria) relative to their prey (including algae and plants).

The study, due to be published online Aug. 25, 2009 in the journal PLoS Biology, looked at a simple underwater food chain and how temperature changes affect organisms’ growth and metabolism. In warmer temperatures, these processes happen faster. As a result, demands for food and nutrients increase with temperature.

Researchers placed tiny zooplankton (consumers in the food chain) and phytoplankton (which are photosynthesizing producers) in small containers and incubated them at different temperatures and in two nutrient scenarios reflecting low and high resource supply conditions for phytoplankton.

The results suggest that higher temperatures could lead to an increase in the number of consumers in the ocean, such as zooxplankton or fish, but a reduction in the overall mass of living creatures in the sea.

Mary O’Connor, Ph.D., the study’s lead author, said the findings have implications for how marine and other ecosystems might respond to global warming.

“Small changes in ocean temperature, like those expected with climate change or even just a warmer summer, have fundamentally different effects on marine consumers and their food supply,” said O’Connor, who carried out the research while a graduate student at UNC and is now a postdoctoral fellow at the National Center for Ecological Analysis and Synthesis in Santa Barbara, Calif. “This means we may be able to understand some important consequences of ocean temperature change before we go out and study temperature effects on every single species.”

“The components of this theory have been around for decades, but I think we are just starting to comprehend the enormous range of processes and patterns in nature that are very strongly influenced by temperature,” said John Bruno, Ph.D., associate professor of marine sciences in the UNC College of Arts and Sciences and a co-author of the study.

Ocean temperature averages about 30 C (86 F) in the tropics and 2 C (35.6 F) in the polar regions, and varies between summer and winter. Climate models predict ocean temperatures will rise between 2 C and 7 C (or between 1 F and 11 F) in different parts of the world in the next 100 years, and increases of 1 C to 4 C (1 F - 9 F) have already been observed. All of these types of changes would affect the food chains of the ocean, O’Connor said.

Other study authors are Michael F. Piehler, Ph.D, assistant professor at the UNC Institute of Marine Sciences in Morehead City, N.C.; Dina M. Leech, Ph.D., formerly a postdoctoral researcher at the institute and now a research scientist at DePauw University; and Andrea Anton, a doctoral student in the UNC curriculum in ecology.

To see the article, visit: http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.1000178.

For a related synopsis in the journal, visit: http://www.plos.org/press/plbi-07-08-OConnorSynopsis.pdf.

Bruno can be reached at (919) 360-7651 or jbruno@unc.edu.
O’Connor can be reached at (805) 892-2522 or oconnor@nceas.ucsb.edu.
Images:
Dina Leech and Virginia Schutte collect zooplankton from Bogue Sound using a plankton tow net. Plankton from the net were rinsed into a sieve and then added to the experimental microcosms. Photo: M. O’Connor

http://uncnews.unc.edu/images/stories/news/science/2009/tfw2%20zoop%20collection.jpg

Mary O’Connor checks temperatures in the food web experiment. Eight water tables each contain five microcosms, which are shielded from UV and full sunlight by plexiglass and window screen. The water bath maintains the temperature, and air tubes going into each microcosm deliver oxygen. Photo: A. Anton

http://uncnews.unc.edu/images/stories/news/science/2009/tfw3%20whole%20expt.jpg

Final microcosm communities. Phyto- and zooplankton are microscopic, but high density of phytoplankton colors the water green. Low densities of phytoplankton, as a consequence of low productivity or heavy grazing by zooplankton, result in clear water. Top to bottom: cold to warm treatments (21 C, 23 C, 25C and 27 C); Left to right: Nutrient additions and nutrient controls. Photo: M. O’Connor

http://uncnews.unc.edu/images/stories/news/science/2009/tfw4final%20food%20webs.png

Concentrated phytoplankton at the end of the experiment. Phytoplankton from 50 mls (1/60) of each microcosm are filtered onto a white filter before the concentration of chlorophyll is measured. Higher density of phytoplankton results in deeper green color. Top to bottom: cold to warm treatments (21 C, 23 C, 25C and 27 C); Left to right: Nutrient additions and nutrient controls. Photo: M. O’Connor and W. Eaton

http://uncnews.unc.edu/images/stories/news/science/2009/tfw5%20plankton%20color.jpg

Patric Lane | Newswise Science News
Further information:
http://www.unc.edu

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: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

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...

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

NASA laser communications to provide Orion faster connections

30.03.2017 | Physics and Astronomy

Reusable carbon nanotubes could be the water filter of the future, says RIT study

30.03.2017 | Studies and Analyses

Unique genome architectures after fertilisation in single-cell embryos

30.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>