Hebrew University researchers surveyed a 5,000 km long strip of the sea and measured the calcification rates of coral reefs and open sea plankton over the whole Red Sea area
Following a 5,000 km long ocean survey, research published in the Proceedings of the National Academy of Sciences presents a new way to measure how the acidification of water is affecting marine ecosystems over an entire oceanic basin.
Figure 1: An aerial photo of a coral reef. Researchers developed a new tool to quantify the effect of ocean acidification on calcifying organisms. (Photo: Boaz Lazar, Hebrew University)
As a result of man-made emissions, the content of CO2 in the atmosphere and oceans has increased dramatically during recent decades. In the ocean, the accumulating CO2 is gradually acidifying the surface waters, making it harder for shelled organisms like corals (Figure 1) and certain open sea plankton to build their calcium carbonate skeletons.
Since this process impacts the functioning of many marine ecosystems, it has been intensively studied in recent years. However, getting an accurate measure is complicated because the effect of ocean acidification on the rates of calcium produced by marine organisms is highly variable and species specific.
Since scientists tend to use local and site-specific field measurements, treating reef environments and open sea environments separately, their measurements reflect the local response of individual organisms to elevated CO2 levels, and not the overall picture.
To get a clearer picture of how ocean acidification is affecting large marine areas, a group of Israeli researchers studied a 5,000 km long strip of ocean (Figure 2), from Eilat to the Seychelles crossing the Red Sea, the Gulf of Aden and the Western Indian Ocean.
The group was led by Profs. Boaz Lazar and Jonathan Erez and the Ph.D. student Zvi Steiner, together with Prof. Amitai Katz, all from the Fredy and Nadine Herrmann Institute of Earth Sciences at the Hebrew University of Jerusalem, together with Prof. Aldo Shemesh and Dr. Ruth Yam of the Weizmann Institute of Science.
The researchers developed a new method to simultaneously assess the overall calcification rates of coral reefs and pelagic (open sea) plankton over a whole oceanic basin, based on variations in surface water chemistry. These variations result from the tendency of organisms that precipitate calcium carbonate skeletons to replace some of the calcium in their skeletons with other elements (e.g. the element strontium).
These replacements depend on growth conditions and are typical for each group of organisms. Owing to this characteristic, corals produce calcium carbonate with a different chemistry than calcareous (composed largely of calcium carbonate) plankton, and their overall effect alters the chemistry of the ocean water. This is the first study that demonstrates the feasibility of quantifying this type of information on an oceanic basin scale.
The group estimated that pelagic plankton precipitate 80% of the Red Sea calcium carbonate, and coral reefs precipitate about 20%. This data is a crucial milestone if we wish to track the effect of anthropogenic activity originating from human actions, since it is not possible to quantify change without having objective baseline conditions.
Monitoring the variations in coral and plankton growth rates every few years can provide essential information regarding rates of environmental change in tropical and subtropical seas like the Red Sea, Caribbean and South China Sea.
The research was published in PNAS (Proceedings of the National Academy of Sciences of the United States of America) as ”Basin scale estimates of pelagic and coral reef calcification in the Red Sea and Western Indian Ocean”. The research was supported by the Israel Science Foundation, the Bill and Melinda Gates Foundation and the Israeli Ministry of Science and Technology.
For information or interviews, contact:
Hebrew University Foreign Press Liaison
02-5882844 / +972-54-8820860
Dov Smith | Hebrew University
New research calculates capacity of North American forests to sequester carbon
16.07.2018 | University of California - Santa Cruz
Scientists discover Earth's youngest banded iron formation in western China
12.07.2018 | University of Alberta
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences