Sedimentation is impacting an entire ecosystem on the seafloor
Melting glaciers are causing a loss of species diversity among benthos in the coastal waters off the Antarctic Peninsula, impacting an entire seafloor ecosystem.
The glacier's meltwater (Potter Cove, King George Island, Antarctica)
Photo: Alfred Wegener Institute / Anders Torstensson
This has been verified in the course of repeated research dives, the results of which were recently published by experts from Argentina, Germany and Great Britain and the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) in a study in the journal Science Advances.
The scientists believe increased levels of suspended sediment in the water to be the cause of the dwindling biodiversity in the coastal region. This occurs when the effects of global warming lead glaciers near the coast to begin melting, as a result of which large quantities of sediment are carried into the seawater.
Over the past five decades, temperatures have risen nearly five times as rapidly on the western Antarctic Peninsula than the global average. Yet the impacts of the resulting retreat of glaciers on bottom-dwelling organisms (benthos) remain unclear.
In response, researchers at Dallmann Laboratory are now mapping and analysing the benthos in Potter Cove, located on King George Island off the western Antarctic Peninsula. Here the Alfred Wegener Institute and the Argentine Antarctic Institute (IAA) operate Dallmann Laboratory as part of the Argentinian Carlini Station. Research concerning benthic flora and fauna has been part of the laboratory’s long-term monitoring programme for more than two decades.
In 1998, 2004 and 2010 divers photographed the species communities at three different stations and at different water depths: the first, near the glacier’s edge; the second, an area less directly influenced by the glacier; and the third, in the cove’s minimally affected outer edge. They also recorded the sedimentation rates, water temperatures and other oceanographic parameters at the respective stations, so that they could correlate the biological data with these values.
Their findings: some species are extremely sensitive to higher sedimentation rates. “Particularly tall-growing ascidians like some previously dominant sea squirt species can’t adapt to the changed conditions and die out, while their shorter relatives can readily accommodate the cloudy water and sediment cover,” explains Dr Doris Abele, an AWI biologist and co-author of the study, adding, “The loss of important species is changing the coastal ecosystems and their highly productive food webs, and we still can’t predict the long-term consequences.”
“It was essential to have a basis of initial data, which we could use for comparison with the changes. In the Southern Ocean we began this work comparatively late,” says the study’s first author, marine ecologist Ricardo Sahade from the University of Cordoba and Argentina’s National Scientific and Technical Research Council CONICET, who is leading the benthic long-term series. “Combining this series of observations, accompanying ecological research on important Antarctic species, and mathematical modelling allows us to forecast the changes to the ecosystem in future scenarios,” adds co-author Fernando Momo from Argentina’s National University of General Sarmiento.
Dallmann Laboratory at Carlini Station (formerly Jubany Station) was first founded in 1994 as a joint facility by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and the Argentine Antarctic Institute (IAA). It has since established itself as a trusted research platform for numerous international and interdisciplinary network programmes, which were supported by the European Union and Argentinian funding organisations throughout the past decade.
“Sustainable long-term research and coordinated, interdisciplinary Antarctic research programmes are essential in order to explain the local changes in coastal ecosystems in connection with global warming,” says Doris Abele. She coordinates the ongoing EU project IMCONet (http://www.imconet.eu) at Dallmann Laboratory, just as she did for previous projects like IMCOAST (http://www.imcoast.org), in which the research underlying the current study was conducted. In addition to our Argentinian partners, researchers from the British Antarctic Survey and the University of Oldenburg also participated in the Science Advances Study.
Ricardo Sahade, Cristian Lagger, Luciana Torre, Fernando Momo, Patrick Monien, Irene Schloss, David K.A. Barnes, Natalia Servetto, Soledad Tarantelli, Marcos Tatián, Nadia Zamboni, Doris Abele: Climate change and glacier retreat drive shifts in an Antarctic benthic ecosystem. Science Advances 2015; DOI: 10.1126/sciadv.1500050
EMBARGOED until Friday, 13 November 2015, 8:00 pm CET, 7:00 London time, 2:00 pm US EST
Notes for Editors:
Printable images can be found following this link: http://multimedia.awi.de/medien/pincollection.jspx?collectionName=%7B6139386e-90...
Your contact partners are Dr Doris Abele (she is travelling at the moment, please send an email to: Doris.Abele(at)awi.de), and at the Department of Communications and Media Relations Dr Folke Mehrtens (phone 0049 471 4831-2007; e-mail: Folke.Mehrtens(at)awi.de).
The Alfred Wegener Institute conducts research in the Arctic, Antarctic and in the high and mid-latitude oceans. The Institute coordinates German polar research and provides important infrastructure such as the research icebreaker Polarstern and research stations in the Arctic and Antarctic to the national and international scientific world. The Alfred Wegener Institute is one of the 18 research centres of the Helmholtz Association, the largest scientific organisation in Germany.
Ralf Röchert | idw - Informationsdienst Wissenschaft
NASA examines Peru's deadly rainfall
24.03.2017 | NASA/Goddard Space Flight Center
Steep rise of the Bernese Alps
24.03.2017 | Universität Bern
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...
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...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy