Enormous quantities of sediment are deposited in the flood-plains traversed by the Amazon and its tributaries in times of flooding. Scientists have hitherto considered the sedimentation rate to be generally constant with time.
Research conducted jointly by the IRD, the Universities of Washington1 and California2 and the Bolivian National Meteorology and Hydrology Service (SENAMHI) of La Paz, on two Bolivian rivers shows on the contrary that such events are irregular and less frequent than has been thought. These results, just published in Nature, emphasize that, in this Andean-Amazonian foreland, sedimentation is closely dependent on the flood amplitude, in turn linked to climatic variability, and particularly to La Niña, the cold phase of the ENSO (El Niño Southern Oscillation).
Continental-scale rivers can transport enormous sediment loads. In periods of flood, a proportion of these is deposited on flood-plains. In the Amazon Basin, crossed by the Earth’s largest river, great volumes of such sequestered sediment accumulations occur. This is especially so in the Llanos, the Bolivian lowland flood-plains which stretch from the foot of the Andes. An estimated 100 to 150 million tonnes of sediment are deposited each year respectively in the Rio Beni and the Rio Mamore flood-plains. These are the two Andean tributaries of the Rio Madeira, one of the Amazon’s main tributaries and source of more than half the sediment load transported by that river.
Marie Guillaume | alfa
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University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
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Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
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Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
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17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Interdisciplinary Research
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20.10.2017 | Earth Sciences