ScienceDaily: Earth & Climate News

Full-annual-cycle models track migratory bird populations throughout the year Posted: 04 Mar 2015 04:02 PM PST Many birds spend only a few months of the year in their breeding range before leaving to spend the winter in another region or even on another continent, and models that only make use of data from one season may not paint a complete picture. For this reason, researchers have written the first comprehensive review of the different types of full-annual-cycle modeling approaches available to ecologists.

Metabolic path to improved biofuel production Posted: 04 Mar 2015 12:26 PM PST Researchers have found a way to increase the production of fuels and other chemicals from biomass fermented by yeast without the need of environmentally harsh pre-treatments or expensive enzyme cocktails.

Direct evidence that drought-weakened Amazonian forests 'inhale less carbon' Posted: 04 Mar 2015 11:14 AM PST Direct evidence of the rate at which individual trees in the Amazonian basin 'inhale' carbon from the atmosphere during severe drought has been provided by an international research team. Researchers found that while the rate of photosynthesis was constant among trees on plots unaffected by drought, rates on the six drought-affected plots dropped significantly (as compared with before the 2010 drought). They also discovered that while the growth rates of drought-affected plots were unchanged, levels of tissue maintenance and the general health of trees were reduced.

Advancing multiple approaches for characterizing permafrost microbes in a changing climate Posted: 04 Mar 2015 10:08 AM PST To better characterize the microbial activities in the thawing permafrost, scientists have reported on the application of multiple molecular technologies: "omics."

Scientists question rush to build Nicaragua canal Posted: 04 Mar 2015 09:41 AM PST A consortium of environmental scientists has expressed strong concern about the impact of a controversial Central American canal across Nicaragua. The path of the Nicaragua Interoceanic Grand Canal to connect the Atlantic and Pacific oceans will cut through Lake Cocibolca (aka Lake Nicaragua), Central America's main freshwater reservoir and the largest tropical freshwater lake of the Americas; this plan will force the relocation of indigenous populations and impact a fragile ecosystem, including species at risk of extinction, they warn.

New models yield clearer picture of emissions' true costs Posted: 04 Mar 2015 08:04 AM PST New models calculate and compare the true costs of various fuels to health, climate and the environment. Viewed this way, a gallon of gas costs $3.80 more than the pump price. The social cost of a gallon of diesel is about $4.80 more than the pump price; the price of natural gas more than doubles; and coal-fired electricity more than quadruples. Solar and wind power, on the other hand, become cheaper than they initially seem.

Experiments support conductivity claims for microbial nanowires Posted: 04 Mar 2015 08:03 AM PST Scientific debate has been hot lately about whether microbial nanowires, the specialized electrical pili of the mud-dwelling anaerobic bacterium Geobacter sulfurreducens, truly possess metallic-like conductivity as its discoverers claim. But now scientists say they have settled the dispute between theoretical and experimental scientists by devising a combination of new experiments and better theoretical modeling.

Reducing greenhouse gas emissions with a more effective carbon capture method Posted: 04 Mar 2015 08:03 AM PST Trapping carbon dioxide (CO2) emissions from power plants and various industries could play a significant role in reducing greenhouse gas emissions in the future. But current materials that can collect CO2 -- from smokestacks, for example -- have low capacities or require very high temperatures to work. Scientists are making progress toward a more efficient alternative that could help make carbon capture less energy intensive.

Traditional beliefs promote sustainability in West Africa Posted: 04 Mar 2015 08:02 AM PST Sacred forests and traditional beliefs are shaping sustainable farming practices in communities in West Africa, according to new research. Scientists carried out a unique 18-month study in Liberia, examining the traditional agriculture of the Loma people where farmers do not use industrial farming practices or artificial fertilizers. They found sacred forests and ancestral lands were valued more than short-term economic gain through increasing food production.

Basis for cadmium toxicity uncovered Posted: 04 Mar 2015 07:43 AM PST Research has uncovered how the metal cadmium, which is accumulating in the food chain, causes toxicity in living cells. "Cadmium is a very important industrial metal, but exposure to it results in accumulation in the food chain, leading to toxicity in animals and humans," says the project. "Exposure to cadmium can occur due to poor disposal of industrial or electronics waste, and also through cigarette smoke and ingestion of contaminated food. While the toxicity of cadmium has been known for a long time, how it causes toxicity and damages cells hasn't been understood."

Where you live could mean 'greener' alternatives do more harm than good Posted: 04 Mar 2015 07:43 AM PST Engineers propose a new 600-ton threshold that could indicate when switching to 'low carbon' alternatives may actually increase emissions. Although regions may welcome "green" technology like electric vehicles, high-speed rail and geothermal heating, they aren't green if the electricity to power them creates even more carbon emissions than their oil-driven counterparts, researchers say.

Amazon deforestation 'threshold' causes species loss to accelerate Posted: 04 Mar 2015 07:42 AM PST One of the first studies to map the impact of deforestation on biodiversity across entire regions of the Amazon has found a clear 'threshold' for forest cover below which species loss becomes more rapid and widespread. By measuring the loss of a core tranche of dominant species of large and medium-sized mammals and birds, and using the results as a bellwether, the researchers found that for every 10% of forest loss, one to two major species are wiped out. This is until the threshold of 43% of forest cover is reached, beyond which the rate of biodiversity loss jumps from between two to up to eight major species gone per 10% of disappeared forest.

Genetic data can help predict how pine forests will cope with climate change Posted: 04 Mar 2015 07:41 AM PST Data from only a small number of gene variants can predict which maritime pine trees are most vulnerable to climate change, scientists report. The results will improve computer models designed to forecast where forests will grow as the climate changes, and promises to help forestry managers decide where to focus reforestation efforts. The results will also guide the choice of tree stocks.

Hurricanes helped accelerate spread of lionfish Posted: 04 Mar 2015 07:40 AM PST Just when you thought hurricanes couldn't get any scarier, think again. Their names roll of the tongue like a rogues' gallery: Floyd, Frances, Irene, Wilma and Andrew. But these aren't the names of notorious criminals; rather, they are just a few of the hurricanes since 1992 that have helped spread invasive marine species throughout the Florida Straits. Researchers have discovered that storms don't only have a dramatic impact on land; they have an equally dramatic effect on ocean currents, which helps the spread of marine invasive species throughout a region.

Wild yaks: Shaggy barometers of climate change Posted: 04 Mar 2015 07:40 AM PST A new study finds that climate change and past hunting in the remote Tibetan Plateau is forcing female wild yaks onto steeper and steeper terrain.

Usual prey gone, a fish survives by changing predictably Posted: 04 Mar 2015 07:40 AM PST Without the Bahamas mosquitofish to eat, bigmouth sleepers slide down the food chain and survive on insects, snails and crustaceans. And, in so doing, sleepers' behaviors, ratio of males to females and physical appearance change, too.

NASA Ames reproduces the building blocks of life in laboratory Posted: 04 Mar 2015 06:35 AM PST NASA scientists studying the origin of life have reproduced uracil, cytosine, and thymine, three key components of our hereditary material, in the laboratory. They discovered that an ice sample containing pyrimidine exposed to ultraviolet radiation under space-like conditions produces these essential ingredients of life.

'No take zones' in English Channel would benefit marine wildlife, fishing industry Posted: 04 Mar 2015 04:54 AM PST Marine conservationists are increasingly pinning their hopes on marine protected areas (MPAs) to save threatened species and reduce over-fishing. However, while most people agree that stopping some types of fishing in MPAs would benefit wildlife and fisheries, working out which fishing activities should be banned is often complicated and controversial.

Grand tree of life study shows a clock-like trend in new species emergence and diversity Posted: 04 Mar 2015 04:54 AM PST Researchers have assembled the largest and most accurate tree of life calibrated to time, and surprisingly, it reveals that life has been expanding at a constant rate. The study also challenges the conventional view of adaptation being the principal force driving species diversification, but rather, underscores the importance of random genetic events and geographic isolation in speciation, taking about 2 million years on average for a new species to emerge onto the scene.

Animal functional diversity started out poor, became richer over time Posted: 04 Mar 2015 04:54 AM PST The finding refutes a hypothesis by the famed evolutionary biologist Stephen J. Gould that marine creatures underwent an 'early burst' of functional diversity during the dawn of animal life.

Why many similar species coexist within complex ecosystems, such as Amazon rainforest or coral reefs Posted: 04 Mar 2015 04:53 AM PST Scientists suggest one possible answer for the enigma of stability in complex ecosystems like the Amazon rainforest or coral reefs. Many similar species coexist in these complex ecosystems without one of them prevailing above all the rest and displacing them.

Vampire bats: Who bit whom? Posted: 04 Mar 2015 04:53 AM PST Scientists discovered a new retrovirus “fossil” found in the common vampire bat which is homologous to retroviruses in rodents and primates. The results suggest the recent circulation of an active infectious retrovirus and cross-species transmission. Vampire bat (Desmodus rotundus) samples from Mexico and from the Berlin Zoological Garden revealed a new endogenous retrovirus (named DrERV after Desmodus rotundus endogenous retrovirus) that is also present in rodents and primates but is absent in other closely related bat species. The results suggest that this virus historically jumped more than once among different species.

New data provided by seabed sediments on the climate within the Mediterranean basin over the course of the last 20,000 years Posted: 04 Mar 2015 04:53 AM PST Scientists have found new data on the weather in the Mediterranean basin over the course of the past 20.000 years thanks to the chemical composition of sediments deposited in its seabed.

Solar cells to get growth boost, price cut Posted: 04 Mar 2015 04:52 AM PST Researchers have found that growing a type of film used to manufacture solar cells in ambient air gives it a growth boost. The finding could make manufacturing solar cells significantly cheaper.

What happens if we all drive electrical vehicles? Posted: 04 Mar 2015 04:52 AM PST The technology behind the design of electric vehicles is ever improving and the EU predicts that these vehicles could be in mass production by 2020. By developing a completely new way of using information from GPS and location data shown by GSM, the EU DATA SIM project simulated the consequences of a massive switch to electric vehicles, and studied the impact on mobility and electricity distribution networks.

Researchers discover new material to produce clean energy Posted: 03 Mar 2015 11:17 AM PST Researchers have created a new thermoelectric material, intended to generate electric power from waste heat -- from a vehicle tailpipe, for example, or an industrial smokestack -- with greater efficiency and higher output power than currently available materials.