Dynamics behind Arctic ecosystems revealed

Species such as the musk ox, Arctic fox and lemming live in the harsh, cold and deserted tundra environment. However, they have often been in the spotlight when researchers have studied the impact of a warmer climate on the countryside in the north. Until now, the focus has been concentrated on individual species, but an international team of biologists has now published an important study of entire food-web dynamics in the journal Nature Climate Change. Field studies covering three continents show that temperature has an unexpectedly important effect on food-web structure, while the relationship between predator and prey is crucial for the food-web dynamics and thereby the entire ecosystem.Temperature is decisive’We have gathered data on all animals and plants characterising the arctic tundra in seven different areas. This has allowed us to generate a picture of how food chains vary over a very large geographical (and, with it, climatic) gradient. Therefore, and for the first time, we can offer an explanation of the factors governing the tundra as an ecosystem,’ says Niels Martin Schmidt from Aarhus University, Denmark, one of the researchers behind the study. The researchers have evidenced that temperature is of decisive importance for which elements form part of the food chain, thus permitting them to predict how climate changes may impact whole food chains — and not just the conditions for the individual species.The largest avoids being eatenTemperature regulates which organisms interact with each other in the far north arctic nature. However, the present study also shows that predation, i.e. the interactions between predators and prey, is the factor regulating the energy flows in ecosystems and, with that, the function of the ecosystem.’Our results show that predators are the most important items of the tundra food chains, except in the High Arctic. The intensity varies with the body size of the herbivores (plant eaters) of the chains. …

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Seal teeth offer glimpse into the environmental past of Russia’s Lake Baikal

March 21 marks World Water Day — and a fitting time to consider one of the most unique mammals in Earth’s waters.The nerpa, also known as the Baikal seal, is the only seal that lives exclusively in fresh water. This earless seal can be found in just one place, Russia’s Lake Baikal, where it is at the top of the food web. And now, Wellesley scientists have found that the teeth of this particular seal may hold the strongest evidence of the effects of decades of environmental pollution, nuclear testing, and climate change on Lake Baikal — the deepest, oldest, and most bio-diverse lake in the world.”The Baikal seal teeth are a chemical record of the lake,” said Marianne Moore, Wellesley Professor of Biological Sciences. By analyzing the chemical composition of hundreds of seal teeth, Professor Moore and her co-researchers, post-doctoral fellow Ted Ozersky and Wellesley student Xiu Ying (Annie) Deng ’15, are working to reconstruct the Baikal seal’s diet and contaminant burdens over the last 80 years. The teeth were collected from ice harvested in the area by fellow scientists in Russia.Baikal seals can live up to 40 and 50 years, and much like the rings of a tree trunk, the layers of dentine within their teeth can be studied and linked to environmental patterns and changes over a period of time. Moore, Ozersky, and Deng are looking for evidence of toxic metals such as uranium, mercury, cadmium, and zinc inside the teeth samples, which date back to the period before industrialization in the region.Why not just measure these toxic elements in the water? Professor Moore explained that these metals show up at extremely low levels in the water. The teeth of the nerpa are actually better indicators due to biomagnification, the process by which the concentration of a substance increases with each level of the food chain. Because the Baikal seal is at the top of its food web, their teeth hold the best clues into the lake’s environmental past.”Ultimately, the goal of our project is to study contamination levels in Lake Baikal as reflected by the seals, and to tie these patterns to changes in the watershed, such as the introduction of mining in the area, an increase in coal burning, and other environmental events,” said Dr. Ozersky.Still early in the project, the Wellesley researchers have already made a surprising discovery: levels of some toxic metals such as uranium were higher in the mid 1970’s than in seals today. …

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World Nations Deny Dangers of Chrysotile Asbestos

Seven nations won out against 143 others in the debate over whether chrysotile asbestos should be added to the United Nation’s Prior Informed Consent (PIC) list of hazardous substances in the Rotterdam Convention. India, Kazakhstan, Kyrgyzstan, Russia, Ukraine, Vietnam, and Zimbabwe all objected to the addition at the sixth meeting of the Rotterdam Convention which took place April 28 – May 10,2013, in Geneva Switzerland. It comes as no surprise that the countries which objected to the listing are home to a booming asbestos industry. Russia alone mines an estimated 1,000,000 tons of asbestos annually and is the supplier for half of the world’s chrysotile production.In September of 2012, Canada, which was the sole objector to the addition at the 2011 conference, announced it would no longer object to the listing. Russia, …

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Asbestos is The Way of Life for Russian Mountain Population

It is unbelievable that there is a place in today’s world where a person’s daily routine could involve shaking asbestos dust off laundry hanging on a clothesline or sweeping asbestos dust out of a window sill to let in the morning light. In the eastern slopes of Russia’s Ural Mountains, such a place does in fact exist.In the recent New York Times article, City in Russia Unable to Kick Asbestos Habit, author Andrew Kramer gives a detailed description of life in the mountain city of Asbest. With a population of 70,000, Asbest is home to the largest open pit asbestos mine in the world. The mine it is about half the size of Manhattan and descends about 1,000 feet down into the earth. The city’s anthem is, “Asbestos, …

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Beware: Flesh Rotting Street Drug "Krokodil"

Krokodil Drug – May Have Come From Russia to the US Over a year ago the nation was shocked by the synthetic drug known as bath salts that was suspected in a horrific act of violence in Miami, Florida. Since then there have been national crackdowns on head shops and gas stations that sold the synthetic drug and news reports of it have dwindled. Last week a new drug, that proves just as, if not more, horrifying than bath salts may have hit the streets in the US.The drug is called “krokodil” because it causes users to break out in scaly sores like a crocodile. These sores aren’t a result of picking, as with meth addicts but from contaminants in the drug that cause human flesh to…

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New superheavy elements can be uniquely identified

Aug. 30, 2013 — An international team of researchers presents fresh evidence that confirms the existence of the superheavy chemical element 115. The experiment was conducted at the GSI Helmholtz Center for Heavy Ion Research, an accelerator laboratory located in Darmstadt. Under the lead of physicists from Lund University in Sweden, the group, which included researchers from Johannes Gutenberg University Mainz (JGU) and the Helmholtz Institute Mainz (HIM), was able to present a way to directly identify new superheavy elements.Share This:Elements beyond atomic number 104 are referred to as superheavy elements. They are produced at accelerator laboratories and generally decay after a short time. Initial reports about the discovery of an element with atomic number 115 were released from a research center in Russia in 2004. The then presented indirect evidence for the new element, however, was insufficient for an official discovery.For the new experiment, scientists at the Institute of Nuclear Chemistry at Mainz University took a sample of the exotic element americium. They deposited an americium layer on a thin foil, which was subsequently bombarded with calcium ions at the GSI facility. For the first time, the exploitation of a new detector system allowed registering photons along with the alpha-decay of the new element and its daughter products. Measured photon energies correspond to those expected for X-rays from these products and thus serve as the element’s fingerprint.”This can be regarded as one of the most important experiments in the field in recent years, because at last it is clear that even the heaviest elements’ fingerprints can be taken”, agreed Professor Dirk Rudolph from Lund University in Sweden and Professor Christoph Düllmann, professor at Mainz University and leading scientist at GSI Darmstadt and HIM. …

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Existence of new element confirmed

Aug. 27, 2013 — An international team of researchers, led by physicists from Lund University, has confirmed the existence of what is considered a new element with atomic number 115. The experiment was conducted at the GSI research facility in Germany. The results confirm earlier measurements performed by research groups in Russia.Share This:“This was a very successful experiment and is one of the most important in the field in recent years”, said Dirk Rudolph, Professor at the Division of Atomic Physics at Lund University.Besides the observations of the new chemical element, the researchers have also gained access to data that gives them a deeper insight into the structure and properties of super-heavy atomic nuclei.By bombarding a thin film of americium with calcium ions, the research team was able to measure photons in connection with the new element’s alpha decay. Certain energies of the photons agreed with the expected energies for X-ray radiation, which is a ‘fingerprint’ of a given element.The new super-heavy element has yet to be named. A committee comprising members of the international unions of pure and applied physics and chemistry will review the new findings to decide whether to recommend further experiments before the discovery of the new element is acknowledged.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by Lund University. Note: Materials may be edited for content and length. For further information, please contact the source cited above. Need to cite this story in your essay, paper, or report? Use one of the following formats: APA MLA Note: If no author is given, the source is cited instead.

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Sea ice decline spurs the greening of the Arctic

Aug. 23, 2013 — Sea ice decline and warming trends are changing the vegetation in nearby arctic coastal areas, according to two University of Alaska Fairbanks scientists.Uma Bhatt, an associate professor with UAF’s Geophysical Institute, and Skip Walker, a professor at UAF’s Institute of Arctic Biology, contributed to a recent review of research on the response of plants, marine life and animals to declining sea ice in the Arctic.”Our thought was to see if sea ice decline contributed to greening of the tundra along the coastal areas,” Bhatt said. “It’s a relatively new idea.”The review appeared in a recent issue of Science magazine. It is a close, comprehensive look at how the losses of northern sea ice affect surrounding areas. Bhatt and Walker were two of ten authors.The review team analyzed 10 years worth of data and research on the subject. The findings show that sea ice loss is changing marine and terrestrial food chains. Sea-ice disappearance means a loss of sea-ice algae, the underpinning of the marine food web. Larger plankton is thriving, replacing smaller, but more nutrient dense plankton. What that means exactly is not yet understood.Above water, loss of sea ice has destroyed old pathways of animal migration across sea ice while opening new pathways for marine animals in others. Some animals and plants will become more isolated. …

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Huge owls need huge trees

Aug. 15, 2013 — A study spearheaded by the Wildlife Conservation Society and the University of Minnesota has shown that the world’s largest owl — and one of the rarest — is also a key indicator of the health of some of the last great primary forests of Russia’s Far East.The study found that Blakiston’s fish owl relies on old-growth forests along streams for both breeding and to support healthy populations of their favorite prey: salmon. The large trees provide breeding cavities for the enormous bird, which has a two-meter (six-foot) wingspan. And when these dead, massive trees topple into adjacent streams, they disrupt water flow, forcing the gushing river around, over, and under these new obstacles. The result is stream channel complexity: a combination of deep, slow-moving backwaters and shallow, fast-moving channels that provide important microhabitats critical to salmon in different developmental stages.The study appears in the August issue of the journal Oryx. Authors include Jonathan Slaght of the Wildlife Conservation Society, R. J. Gutiérrez of the University of Minnesota, and Sergei Surmach of the Institute of Biology and Soils (Russian Academy of Sciences).The authors studied the foraging and nesting characteristics of Blakiston’s fish owl in Primorye, Russia, where they looked at nesting habitat over 20,213 square kilometers (7,804 square miles). They found that large old trees and riparian old-growth forest were the primary distinguishing characteristics of both nest and foraging sites.The authors say that management and conservation of old-growth forests is essential for sustaining this species because they are central to the owls’ nesting and foraging behavior. Moreover, conservation of Primorye’s forests and rivers sustains habitat for many other species: including eight salmon and trout species that spawn there; some of the 12 other owl species found in Primorye; and mammals like the endangered Amur (or Siberian) tiger, Asiatic black bear, and wild boar. …

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Ancient viruses that function in early human development may play role in cancer

July 31, 2013 — The St. Laurent Institute, a non-profit medical research institute focused on the systems biology of disease, today announced in a study published in the July edition of Genome Biology, that genetic matter, previously ignored by the scientific community, may play an important role in cancer. The study, “VlincRNAs controlled by retroviral elements are a hallmark of pluripotency and cancer” found that novel non-coding parts of the human genome known as vlincRNAs (very long intergenic, non-coding RNAs) triggered by ancient viruses, participate in the biology of stem cells, and in the development of cancer. Importantly, the group of researchers from U.S., Europe and Russia found that the elimination of these vlincRNAs caused the death of cancer cells.Share This:”Understanding this previously ignored part of the human genome, its role in human development, and how it may be taken over by disease, opens a new frontier in science with important implications for medical advances,” said Philipp Kapranov, Ph.D., lead researcher at the St. Laurent Institute. “Future research into the role and function of vlincRNAs holds promise for both highly targeted diagnostic tests and more precise cancer treatments.Up to 98 percent of human genomic matter is known as “junk” or “dark matter” non-coding DNA, and had for years attracted little interest among scientists who doubted its role in human health and disease. Recent research has begun to identify that part of that non-coding DNA is used by the cell to make RNA such as vlincRNA, highly tissue-specific RNA chains of unusually large lengths, many of which are only found in embryonic or cancerous cells. VlincRNAs found in these two types of cells tend to be expressed based upon genetic signals from ancient viruses that invaded our ancestors’ genome millions of years ago and were gradually “domesticated” over evolutionary time. The number of vlincRNAs expressed by these domesticated viral sequences correlates with both embryonic development and malignant cancers.”St. Laurent Institute has adapted true single-molecule sequencing technology to global transcriptome analysis, providing state-of-the-art technology for the measurement of the output of the human genome,” said Georges St. …

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Egg donation in European clinics: Why do women do it?

July 8, 2013 — Egg donation is now one of the major reasons why couples travel abroad for fertility treatment. Because this growing trend may circumvent regulations at home or raise concerns about financial inducement, it has also become one of the most controversial. Yet little is known about the women who provide the donor eggs in overseas clinics — their characteristics, their motivation and their compensation.A study performed by ESHRE, which surveyed (by questionnaire) 1423 egg donors at 60 clinics in 11 European countries, has now found that the majority of donors are keen to help infertile couples for altruistic reasons, but a large proportion also expect a personal benefit, usually financial.(1,2)The study was performed during 2011 and 2012 by ESHRE’s Task Force on Cross-border Reproductive Care and European IVF Monitoring Consortium, with the results presented today by the chairman of the Task Force, Professor Guido Pennings of the Bioethics Institute Ghent, Belgium. The donor’s age proved an important factor in her motivation to donate. While the overall average age of the donors in this study was relatively young (27.4 years, ranging from 25.6 in Spain to 31 years in France), there was a significant effect of age on altruistic motives: 46% of the donors under 25 noted altruism alone as their motive compared to 79% of those over 35; 12% of those under 25 were purely financially motivated compared to 1% of those older than 35. The younger you are, apparently, the more is money a motivation.Among the donor groups identified in the study population were:Students (18% in Spain, 16% Finland, 13% Czech Republic) Unemployed (24% in Spain, 22% Ukraine, 17% Greece) Fully employed (75% in Belgium, 70% Poland, 28% Spain) Single women (50%+ in Spain and Portugal, 30% Greece) Other findings showed that around one-third of all study donors had a university degree, and around one half all donors had a child of their own. Why do donors go through a demanding IVF treatment cycle to donate eggs? The study firstly found that, while altruism was the principal motive overall, the majority of donors did receive financial compensation. “The fact that a person receives compensation or money does not mean that she is motivated by that money,” said Professor Pennings. However, the study made it clear that financial compensation is still an important motivation for many donors, especially in certain countries. …

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Rocket-launched camera reveals highways and sparkles in the solar atmosphere

June 30, 2013 — Using an innovative new camera on board a sounding rocket, an international team of scientists have captured the sharpest images yet of the Sun’s outer atmosphere. The team discovered fast-track ‘highways’ and intriguing ‘sparkles’ that may help answer a long-standing solar mystery. Prof. Robert Walsh of the University of Central Lancashire (UCLan) will present the new results on Monday 1 July at the RAS National Astronomy Meeting in St Andrews, Scotland.With partners in the United States and Russia, the UCLan team used a sounding rocket to launch the NASA High Resolution Coronal Imager (Hi-C) from the White Sands Missile Range in New Mexico, USA. During its short flight, the Hi-C team obtained images of the solar atmosphere (the solar corona) five times sharper than anything seen before and acquired data at a rate of about one image every five seconds.The new camera observed the Sun in extreme ultraviolet light and focused on a large, magnetically-active sunspot region. Images from Hi-C reveal a number of new features in the corona, including ‘blobs’ of gas ricocheting along ‘highways’ and bright dots that switch on and off rapidly which the group call ‘sparkles’.In the new images, small clumps of electrified gas (plasma) at a temperature of about one million degrees Celsius are seen racing along highways shaped by the Sun’s magnetic field. These blobs travel at around 80 km per second (the equivalent of 235 times the speed of sound on Earth), fast enough to travel the distance from Glasgow to London in 7 seconds. The highways are 450 km across, roughly the length of Ireland from north to south.The flows of material are inside a so-called solar filament, a region of dense plasma that can erupt outwards from the Sun. These eruptions, known as coronal mass ejections (CMEs), carry billions of tonnes of plasma into space. If a CME travels in the right direction it can interact with Earth, disturbing the terrestrial magnetic field in a ‘space weather’ event that can have a range of destructive consequences from damaging satellite electronics to overloading power grids on the ground. …

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As climate changes, boreal forests to shift north and relinquish more carbon than expected

May 5, 2013 — It’s difficult to imagine how a degree or two of warming will affect a location. Will it rain less? What will happen to the area’s vegetation?

New Berkeley Lab research offers a way to envision a warmer future. It maps how Earth’s myriad climates — and the ecosystems that depend on them — will move from one area to another as global temperatures rise.

The approach foresees big changes for one of the planet’s great carbon sponges. Boreal forests will likely shift north at a steady clip this century. Along the way, the vegetation will relinquish more trapped carbon than most current climate models predict.

The research is published online May 5 in the journal Nature Geoscience.

Boreal ecosystems encircle the planet’s high latitudes, covering swaths of Canada, Europe, and Russia in coniferous trees and wetlands. This vegetation stores vast amounts of carbon, keeping it out of the atmosphere where it can contribute to climate change.

Scientists use incredibly complex computer simulations called Earth system models to predict the interactions between climate change and ecosystems such as boreal forests. These models show that boreal habitat will expand poleward in the coming decades as regions to their north become warmer and wetter. This means that boreal ecosystems are expected to store even more carbon than they do today.

But the Berkeley Lab research tells a different story. The planet’s boreal forests won’t expand poleward. Instead, they’ll shift poleward. The difference lies in the prediction that as boreal ecosystems follow the warming climate northward, their southern boundaries will be overtaken by even warmer and drier climates better suited for grassland.

And that’s a key difference. Grassland stores a lot of carbon in its soil, but it accumulates at a much slower rate than is lost from diminishing forests.

“I found that the boreal ecosystems ringing the globe will be pushed north and replaced in their current location by what’s currently to their south. In some places, that will be forest, but in other places it will be grassland,” says Charles Koven, a scientist in Berkeley Lab’s Earth Sciences Division who conducted the research.

“Most Earth system models don’t predict this, which means they overestimate the amount of carbon that high-latitude vegetation will store in the future,” he adds.

Koven’s results come from a new way of tracking global warming’s impact on Earth’s mosaic of climates. The method is based on the premise that as temperatures rise, a location’s climate will be replaced by a similar but slightly warmer climate from a nearby area. The displaced climate will in turn shift to another nearby location with a slightly cooler climate. It’s as if climate change forces warmer climates to flow toward cooler areas, making everywhere warmer over time.

This approach can help determine where a given climate is going to in the future, and where a given climate will come from.

Koven applied this approach to 21 climate models. He used simulations that depict a middle-of-the-road climate change scenario, meaning the range of warming by the end of this century is 1.0°C to 2.6°C above a 1986 to 2005 baseline.

Climate models divide the planet into gridcells that cover tens or hundreds of square kilometers. In each model, Koven identified which gridcells in a warmer climate have a nearby gridcell with a similar climate in terms of average monthly temperature and precipitation. A good match, for example, is a neighboring gridcell that has similar rainfall patterns but is slightly warmer in the summer and winter.

Koven then calculated the speed at which a gridcell’s climate will shift toward its matching gridcell over the next 80 years. He also investigated how this shift will transport the carbon stored in the vegetation that grows in the gridcell’s climate.

In general, he found that climates move toward the poles and up mountain slopes. In parts of South America, warmer climates march westward up the Andes. In the southern latitudes, warmer climates head south.

But the most dramatic changes occur in the higher latitudes. Here, boreal ecosystems will have to race poleward in order to keep up with their climates. They’ll also be encroached by warmer climates from the south. By the end of this century, a forest near Alberta, Canada will have to move 100 miles north in order to maintain its climate. And it will gain a climate that is now located 100 miles to the south.

Forests can’t adapt this quickly, however, meaning that in the short-term they’ll be stressed. And in the long-term they’ll be forced to move north and give up their southern regions to grassland.

Only one of the Earth system models shows this precipitous loss of carbon in southern boreal forests. Koven says that’s because most models don’t account for random events such as fire, drought, and insects that kill already-stressed trees. His “climate analogue” approach does account for these events because they’re implicit in the spatial distribution of ecosystems.

In addition, Earth system models predict carbon loss by placing vegetation at a given point, and then changing various climate properties above it.

“But this approach misses the fact that the whole forest might shift to a different place,” says Koven.

This research was supported by the U.S. Department of Energy’s Office of Science.

Explore the “Climate Analog Tracker,” an online tool that enables users to see how climates may shift in the decades to come.

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