A recently published study on how natural and man-made sources of nitrogen are recycled through the Lake Tahoe ecosystem provides new information on how global change may affect the iconic blue lake.

“High-elevation lakes, such as Lake Tahoe, are sentinels of climate change,” said Lihini Aluwihare, associate professor of geosciences at Scripps Institution of Oceanography (SIO) at UC San Diego and co-author of the study. “Small changes in the lake's chemistry can have big impacts on the entire ecosystem.”

Lake Tahoe's nitrogen concentration is one of several factors that helps maintain its crystal clear waters. To keep Tahoe blue in the future, the researchers say it's important to keep a close eye on the nitrogen balance in the ecosystem over time.

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La restauración de los humedales puede reducir las emisiones de gases de efecto invernadero. Esto se muestra en un informe que se ha escrito en parte por investigadores de la Universidad de Gotemburgo.

Los antiguos humedales que han sido drenados y que se utilizan actualmente para la silvicultura y la agricultura emiten 11,4 millones de toneladas de dióxido de carbono equivalente. Esto se puede comparar con el total de emisiones de Suecia de 57,6 millones de toneladas. Pero en el informe de Suecia a la Convención del Clima, las emisiones de turba desecada no son visibles ya que se incluyen con el crecimiento de los bosques.

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Harvesting fire-killed trees is an effective way to reduce woody fuels for up to four decades following wildfire in dry coniferous forests, a U.S. Forest Service study has found.

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When a 7.9-magnitude earthquake struck central China's Sichuan province in 2008, seismic waves rippled through the region, toppling apartment houses in the city of Chengdu and swaying office buildings 1,000 miles away in Shanghai.

Though destructive, earthquakes provide benefit in one respect: they help researchers learn about the structure of the Earth, which in turn could lead to more accurate predictions of damage from future quakes and volcanic activity. By eavesdropping on the seismic vibrations of quakes as they rumble through the Earth, researchers can detect the existence of structures such as mineral deposits, subterranean lakes, and upwellings of magma. Thanks to a growing earthquake detection network and superfast computers, geoscientists are now able to explore the Earth's interior, a region that has been more inaccessible than the deepest ocean or the farthest planet in our solar system. 

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The first 3D reconstruction of the skull of a 360 million-year-old near-ancestor of land vertebrates has been created by scientists from the Universities of Bristol and Cambridge. 

The 3D skull, which differs from earlier 2D reconstructions, suggests such creatures, which lived their lives primarily in shallow water environments, were more like modern crocodiles than previously thought. 

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High social status has its privileges ­­when it comes to aging – even in wild animals.

In a first-of-its-kind study involving a wild species, Michigan State University researchers have shown that social and ecological factors affect animal health. The results, published in the current issue of Biology Letters, focused on spotted hyenas in Kenya.

“High-ranking members in hyena clans reproduce more, they live longer and appear to be in better overall health,” said Nora Lewin, MSU doctoral student of zoology and co-lead author. “If you want to see the hierarchy of spotted hyenas, throw down some fresh meat near them. It’s quickly apparent who’s dominant and who’s not.”

But Lewin wondered if long-accepted biological markers would support what she was seeing in the field. Thanks to working with fellow lead author Kay Holekamp, MSU zoologist, and her long-running hyena experiment, Lewin had access to more than 25 years of data and was able to spend a summer afield in Kenya, observing hyenas’ social structure firsthand.

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