The finding, based on research by University of North Carolina at Chapel Hill marine scientist Justin Ries, could have important implications for ocean food webs and the multi-billion dollar global market for shellfish and crustaceans.
Previous research has shown that ocean acidification – the term for falling pH levels in the Earth’s oceans as they absorb increasing amounts of carbon dioxide (CO2) from the atmosphere – is likely to slow the growth or even dissolve the shells of such creatures.
However, the new study, published in the December issue of the journal Geology, suggests that sediment-dwelling marine organisms may exhibit a wider range of responses to CO2-induced acidification than previously thought: some may get weaker while others become stronger.
Researchers also found that creatures whose shells grew the most, such as crabs, tend to prey on those whose shells weakened the most, such as clams.
Such changes could have serious ramifications for predator and prey relationships that have evolved over hundreds of millions of years, said Ries, Ph.D., assistant professor of marine sciences in the UNC College of Arts and Sciences.
“There is no magic formula to predict how different species will respond, but one thing you can be sure of is that ecosystems as a whole will change because of these varied individual responses,” Ries said.
Researchers grew 18 different species of economically and ecologically important marine calcifiers (creatures that make their shells out of calcium carbonate) at various levels of CO2 predicted to occur over the next several centuries. When CO2 combines with water, it produces carbonic acid, raising the overall amount of carbon in seawater but reducing the amount of the carbonate ion used by organisms in their calcification.
Seven species (crabs, lobsters, shrimp, red and green calcifying algae, limpets and temperate urchins) showed a positive response, meaning they calcified at a higher rate and increased in mass under elevated CO2. Ten types of organisms (including oysters, scallops, temperate corals and tube worms) had reduced calcification under elevated CO2, with several (hard and soft clams, conchs, periwinkles, whelks and tropical urchins) seeing their shells dissolve. One species (mussels) showed no response.
“Shelled marine organisms need carbonate ions to build their shells that protect them from the intense predation that defines everyday life on the shallow sea floor,” Ries said. “The organisms that responded positively to higher CO2 levels are apparently more adept at converting the elevated dissolved inorganic carbon in the seawater, which results from elevated atmospheric CO2, back into a form that they can use directly in their calcification. The others, however, appear to be less adept at manipulating dissolved inorganic carbon.”
Ries said the varied responses may reflect differences in organisms’ ability to regulate pH levels at their sites of calcification; their ability to generate a protective organic layer that limits their exposure to surrounding seawater; whether they use more soluble forms of calcium carbonate in their shells; and their ability to utilize CO2 directly via photosynthesis.
The co-authors of the Geology study are Anne L. Cohen and Daniel C. McCorkle from Woods Hole Oceanographic Institution, Woods Hole, Mass.Images:
To see the effect of different CO2 levels on a sea urchin, go to: http://uncnews.unc.edu/images/stories/news/science/2009/pencil%20urchin_credit%20justin%20ries.jpg
Ries’ Web page: http://www.unc.edu/~jries/
Media note: Ries can be reached at (919) 536-9070 or email@example.com.
Patric Lane | Newswise Science News
More than 100 years of flooding and erosion in 1 event
28.03.2017 | Geological Society of America
Satellites reveal bird habitat loss in California
28.03.2017 | Duke University
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...
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...
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...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
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...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Life Sciences
28.03.2017 | Information Technology
28.03.2017 | Physics and Astronomy