Just as cooking helps people digest food, pretreating polycarbonate plastic -- source of a huge environmental headache because of its bisphenol A (BPA) content -- may be the key to disposing of the waste in an eco-friendly way, scientists have found. Their new study is in ACS' Biomacromolecules.
Mukesh Doble and Trishul Artham note that manufacturers produce about 2.7 million tons of plastic containing BPA each year. Polycarbonate is an extremely recalcitrant plastic, used in everything from screwdriver handles to eyeglass lenses, DVDs, and CDs. Some studies have suggested that the BPA may have a range of adverse health effects, sparking the search for an environmentally safe way of disposing of waste plastic to avoid release of BPA.
The scientists pretreated polycarbonate with ultraviolet light and heat and exposed it to three kinds of fungi -- including the fabled white-rot fungus, used commercially for environmental remediation of the toughest pollutants. The scientists found that fungi grew better on pretreated plastic, using its BPA and other ingredients as a source of energy and breaking down the plastic. After 12 months, there was almost no decomposition of the untreated plastic, compared to substantial decomposition of the pretreated plastic, with no release of BPA.
Source: http://www.sciencedaily.com/releases/2010/01/100127113753.htm
Wednesday, February 3, 2010
Greenhouse Gas Carbon Dioxide Ramps Up Aspen Growth
That is the finding of a new study of natural stands of quaking aspen, one of North America's most important and widespread deciduous trees. The study, by scientists from the University of Wisconsin-Madison and the University of Minnesota at Morris (UMM) and published December 4 in the journal Global Change Biology, shows that elevated levels of atmospheric carbon dioxide during the past 50 years have boosted aspen growth rates by an astonishing 50 percent."Trees are already responding to a relatively nominal increase in atmospheric carbon dioxide over the past 50 years," says Rick Lindroth, a UW-Madison professor of ecology and an expert on plant responses to climate change. Lindroth, UW-Madison colleague Don Waller, and professors Christopher Cole and Jon Anderson of UMM conducted the new study.
The study's findings are important as the world's forests, which cover about 30 percent of the Earth's land surface, play an important role in regulating climate and sequestering greenhouses gases. The forests of the Northern Hemisphere, in particular, act as sinks for carbon dioxide, helping to offset the increase in levels of the greenhouse gas, widely viewed as a threat to global climate stability.
What's more, according to the study's authors, the accelerated growth rates of aspen could have widespread unknown ecological consequences. Aspen is a dominant tree in mountainous and northern forested regions of North America, including 42 million acres of Canadian forest and up to 6.5 million acres in Wisconsin and Minnesota. Aspen and their poplar cousins are considered "foundation species," meaning they exert a strong influence on the plant and animal communities and dynamics of the forest ecosystems where they reside.
"We can't forecast ecological change. It's a complicated business," explains Waller, a UW-Madison professor of botany. "For all we know, this could have very serious effects on slower growing plants and their ability to persist."
Carbon dioxide, scientists know, is food for plants, which extract it from the air and through the process of photosynthesis convert it to sugar, plant food.
Previously, scientists have shown that plants and trees in growth chambers respond to levels of carbon dioxide well above levels in the atmosphere. The new study is the first to show that aspen in their native forest environments are already growing at accelerated rates due to rising ambient levels of carbon dioxide in the atmosphere.
"It's a change hiding right in front of us," says Cole, a biologist at UMM. "Aspens respond to all sorts of things we had to account for -- water, genetics and other factors -- but the strong response to carbon dioxide surprised all of us."
The study measured the growth rates of 919 trees from Wisconsin forests dominated by aspen and birch. Trees ranging in age from 5 to 76 years old were sampled and subjected to tree-ring analysis. Comparing the tree-ring data, a measure of annual tree growth, with records of atmospheric carbon dioxide, the researchers were able to correlate increased rates of growth with changes in the chemistry of the air.
The surprising increase in growth rates for the trees sampled in the study is coupled, the authors note, with moist conditions. By contrast, aspen in the western United States do not seem to grow as fast as those in the American Midwest, most likely due to recent extended periods of drought. Also, while the researchers found that aspen grow much faster in response to elevated carbon dioxide, similar effects have not been observed in other trees species, notably oak and pine.
Findings from the new study, the authors note, could augur revisions of the estimates of how much carbon northern temperate northern forests can sequester.
"Forests will continue to be important to soak up anthropogenic carbon dioxide," says Waller. "But we can't conclude that aspen forests are going to soak up excess carbon dioxide. This is going to plateau."
"Aspens are already doing their best to mitigate our inputs," agrees Cole. "The existing trees are going to max out in a couple of decades."
The new study was funded by the National Science Foundation and UMM.
Source: http://www.sciencedaily.com/releases/2009/12/091204092445.htm
Marine Lab Hunts Subtle Clues to Environmental Threats to Blue Crabs
Science Daily: The Atlantic blue crab, Callinectes sapidus, long prized as a savory meal at a summer party or seafood restaurant, is a multi-million dollar source of income for those who harvest, process and market the crustacean along the U.S. Atlantic and Gulf coasts.
Unfortunately, the blue crab population has been declining in recent years under the assault of viruses, bacteria and man-made contaminants. The signs of the attack often are subtle, so researchers from the National Institute of Standards and Technology (NIST) and the College of Charleston (CofC) are at work trying to identify the clues that will finger specific, yet elusive, culprits.Pathogens and pollutants impair the blue crab’s metabolic processes, the chemical reactions that produce energy for cells. These stresses should cause tell-tale changes in the levels of metabolites, small chemical compounds created during metabolism. Working at the Hollings Marine Laboratory (HML) in Charleston, S.C., the NIST/CofC research team is using a technology similar to magnetic resonance imaging (MRI) to identify and quantify the metabolites that increase in quantity under common environmental stresses to blue crabs — metabolites that could be used as biomarkers to identify the specific sources.
In a recent paper in Metabolomics, the HML research team describes how it used nuclear magnetic resonance (NMR) spectroscopy to study challenges to one specific metabolic process in blue crabs: oxygen uptake. First, the researchers simulated an environmentally acquired bacterial infection by injecting crabs with the bacterium Vibrio campbellii. This pathogen impairs the crab's ability to incorporate oxygen during metabolism. Using NMR spectroscopy to observe the impact on metabolite levels, the researchers found that the yield of glucose, considered a reliable indicator of mild oxygen starvation in crustaceans, was raised.
In a second experiment, the HML team mimicked a chemical pollutant challenge by injecting blue crabs with a chemical (2,4-dinitrophenol (DNP)) known to inhibit oxidative phosphorylation, a metabolic process that manufactures energy. This time, the metabolite showing up in response to stress was lactate, the same compound seen when our muscles need energy and must take in oxygen to get more produced. A rise in the amount of lactate proved that the crabs were increasing their oxygen uptake in response to the chemical exposure.
"Having the glucose and lactate biomarkers -- and the NMR spectroscopy technique to accurately detect them -- is important because the blue crab's responses to mild, non-lethal metabolic stresses are often so subtle that they can be missed by traditional analyses," says Dan Bearden, corresponding author on the HML paper.
The research was supported in part by the National Science Foundation.
The HML is a partnership of governmental and academic agencies including NIST, NOAA's National Ocean Service, the South Carolina Department of Natural Resources, the College of Charleston and the Medical University of South Carolina.
Source: http://www.earthportal.org/news/?p=3104
Monday, January 18, 2010
World's least known bird" found breeding in Afghanistan
NEW YORK (Reuters Life!) – Researchers have found in Afghanistan the first known breeding area of the large-billed reed warbler, which was dubbed in 2007 as "the world's least known bird species."
Researchers for the Wildlife Conservation Society and Sweden's Gothenburg University said they had found the breeding area in the remote and rugged Wakhan Corridor of north-eastern Afghanistan that has escaped the worst effects of war.
They used field observations, museum specimens, DNA sequencing, and the first known audio recording of the species to find the birds and verified the discovery by capturing and releasing almost 20 birds, the largest number ever recorded.
A preliminary paper on the finding appears in BirdingASIA, describing the discovery in Afghanistan as "a watershed moment" in the study of this bird.
The first specimen of the large-billed reed warbler was discovered in India in 1867 but the second find was not until 2006 in Thailand.
"Practically nothing is known about this species, so this discovery of the breeding area represents a flood of new information on the large-billed reed warbler," said Colin Poole of WCS's Asia Program, in a statement.
"This new knowledge of the bird also indicates that the Wakhan Corridor still holds biological secrets and is critically important for future conservation efforts in Afghanistan."
The find came after Robert Timmins from the WCS was conducting a survey of bird communities in the area.
The Wakhan Corridor has escaped the worst effects of the long years of war suffered elsewhere in Afghanistan since the December 1979 invasion by the Soviet Union. The corridor, populated primarily by Wakhi farmers and yurt-dwelling Kyrghyz herders, is also home to snow leopards and wild Marco Polo sheep.
Timmins heard a distinctive song coming from a small, olive-brown bird with a long bill which he taped and later discovered to be a large-billed reed warbler.
The following summer WCS researchers returned to the same area and used a recording of the song to bring out others and catch almost 20 birds for examination.
The WCS said it is currently the only organization conducting scientific conservation studies in Afghanistan, the first such efforts in over 30 years, and it has contributed to a number of conservation initiatives in tandem with the Afghan government.
It helped produce Afghanistan's first list of protected species, an action that has led to a ban on hunting snow leopards, wolves, brown bears, and other species.
(Reporting by Belinda Goldsmith, Editing by Miral Fahmy)
Source: http://news.yahoo.com/s/nm/20100118/lf_nm_life/us_bird_afghanistan
Saturday, January 2, 2010
Mayon folk head home; alert level lowered to 3
GUINOBATAN, ALBAY—Residents who had fled their homes in fear of an eruption of Mayon Volcano were overjoyed to learn early Saturday that the alert level had been lowered from four to three on a five-point scale.
“Definitely it is over... for now,” Albay Gov. Joey Salceda was quoted by wire reports as saying.
He said he had allowed most evacuees to go home but that those living in two barangays near the volcano—or the 6-kilometer permanent danger zone—would have to remain in evacuation centers.
Salceda said all families leaving the temporary shelters would be provided food rations for three days and cash for home repairs.
“Wow! We can go home after half a month here,” Nora Apuyan exclaimed, adding that she and her family would pack their stuff while awaiting confirmation and a go-signal from Mayor Juaning Garcia.
Apuyan, 42, was among the residents of Barangay Maninila who were sheltered at the newly built permanent evacuation center donated by an agency of Spain.
In its latest bulletin issued Saturday morning, the Philippine Institute of Volcanology and Seismology (Phivolcs) lowered Mayon’s alert level from four (meaning a hazardous eruption was possible in days) to three (meaning there was less probability of a hazardous eruption).
Phivolcs said an overall gradual decrease in volcanic activities had prompted it to lower the alert level.
“However, [this] should not be interpreted that the unrest of the volcano has ceased,” it added.
At the peak of the alert, close to 50,000 people were being sheltered in public schools and other evacuation centers in Albay.
Homeward bound
The Joint Task Force Mayon (JTFM) started transporting the evacuees back to their homes Saturday morning.
The evacuees were given relief goods including 15 kilos of rice and P1,400 “cash for work” from President Macapagal-Arroyo through the Department of Social Welfare and Development.
A P15-million fund for farm rehabilitation (including two tractors from the Department of Agriculture) that was originally secured by the provincial government for upland areas is to be realigned to barangays around Mayon.
Capt. Razaleigh G. Bansawan, the JTFM spokesperson, said 25 military vehicles composed of 15 six-by-six trucks and 10 Korean-made KM450 vehicles had been dispatched to various shelters in Albay as of noon Saturday to transport the evacuees.
Roads within the 8-km extended danger zone were ordered opened for the passage of the evacuees.
The Bureau of Fire and Protection was also ordered to clean up the schools vacated by the evacuees in preparation for the resumption of classes on Monday.
The Phivolcs reminded the public that the 6-km permanent danger zone around Mayon and the 7-km extended danger zone on its southeast sector are off-limits to human activities because of “sudden explosions that may generate hazardous volcanic flows.”
As well, it reminded residents near the danger zones to be wary of “post-eruption activity, such as rock falls, pyroclastic flows and ash fallout, which can also occur any time due to the instability of lava deposited on steep slopes.”
Bansawan said checkpoints would be “repositioned” to prevent people, particularly farmers and tourists, from entering the restricted areas.
‘Miracle’
Vilma Ostria said she and her family had been staying with other Maninila residents at the evacuation center since Dec. 15, and constantly worrying over their household and farm.
“We want so much to go home,” the 45-year-old mother of seven told the Inquirer.
Ostria said she and her husband had been praying that their farm produce would not be wasted.
“Our tomatoes, which we will start harvesting by the end of this month, were spared by the ashfall. That’s a miracle, and that’s because of our strong faith in God,” Ostria said.
She said they had feared the loss of more than P50,000 in possible earnings from their half-hectare tomato farm, aside from the root crops that made up their daily food consumption along with rice and vegetables.
Ostria said no one would give them that kind of money if they lost the crops to thieves. “That’s why heads of families can’t just abandon their farms and stay in evacuation centers,” she said.
Widow Solidad Osila, 70, said she was happy to be told to prepare to decamp. “The sleepless nights are over. We sleep late at night here at the evacuation center, unlike at home where we sleep as early as 7 or 8 p.m.,” she said.
Like an island
Maninila is like an island whenever it is swamped by lahar (or volcanic mudflow) because it is surrounded by two rivers.
Mayon’s eruption in August 2006 caused no immediate deaths, but the following December, a passing typhoon unleashed an avalanche of lahar from its slopes that left about 1,000 dead.
Rosito Padua, a member of Maninila’s barangay council, said the disruption of the people’s livelihood was one of the worst effects of Mayon’s current unrest.
“We really don’t trust Mayon even if it is already slowing down, and as barangay officials, we will continue to be vigilant,” he said.
Padua said the evacuation had taken a toll on the earning capacity of the farmers, who should have made a number of harvests.
He said some farmers were able to make just one harvest, thus barely earning capital for the next planting season.
Padua recalled that during Mayon’s eruption in 1993, the residents of Maninila and of the adjacent Barangay Tandarora had to flee under a cloud of ash that billowed and settled on their rice farms.
“Thank God no one was killed,” he said.
Marieta Lacza, a mother of four who owns a sari-sari store in Maninila, brought her small business to the evacuation center in Barangay Travesia so that she could continue paying for her loan.
“Sales at the evacuation center are better because there are many buyers. But it is still the comfort of our home that we prefer because we can do other things, such as farming and other jobs.” said Lacza, 44.
Preemptive evacuation
The residents evacuated from the 6-km permanent danger zone totaled 12,803 (or 2,728 families) from 20 barangays in the cities of Ligao, Tabaco and Legazpi and the towns of Guinobatan, Camalig, Daraga, Sto. Domingo and Malilipot.
They were evacuated as early as the night of Dec. 14, when alert level three was declared.
The number rose to 47,285 (or 9,946 families) when the alert level was raised to four at 12 noon on Dec. 20, after 34,482 (or 7,218 additional families) were evacuated from the extended danger zones.
But many evacuees complained that the temporary shelters, mainly public schools, had inadequate facilities and food supplies.
Elba Bana, 60, said she was happy to go home.
But she added: “We are always afraid, especially when the rain is strong and there may be lahar. If there is strong rain, then we may be evacuated again.”
Governor Salceda said the preemptive evacuation had shown that the Philippines was well prepared in the case of a future eruption.
“We have proven already that we can easily bring [the people] back to the evacuation centers,” he said.
Prayer and plea
Salceda thanked everyone who had assisted the provincial government in the preemptive evacuation of residents.
“Thank you for the prayers,” he said, adding that it was the 12th time Albay had implemented a preemptive evacuation.
Salceda said a preemptive evacuation was “a community prayer in humility to God’s will and respect for nature, and similarly, a collective plea to preempt the disaster from materializing
Source: http://newsinfo.inquirer.net/inquirerheadlines/nation/view/20100102-245202/Definitely-over-for-now
“Definitely it is over... for now,” Albay Gov. Joey Salceda was quoted by wire reports as saying.
He said he had allowed most evacuees to go home but that those living in two barangays near the volcano—or the 6-kilometer permanent danger zone—would have to remain in evacuation centers.
Salceda said all families leaving the temporary shelters would be provided food rations for three days and cash for home repairs.
“Wow! We can go home after half a month here,” Nora Apuyan exclaimed, adding that she and her family would pack their stuff while awaiting confirmation and a go-signal from Mayor Juaning Garcia.
Apuyan, 42, was among the residents of Barangay Maninila who were sheltered at the newly built permanent evacuation center donated by an agency of Spain.
In its latest bulletin issued Saturday morning, the Philippine Institute of Volcanology and Seismology (Phivolcs) lowered Mayon’s alert level from four (meaning a hazardous eruption was possible in days) to three (meaning there was less probability of a hazardous eruption).
Phivolcs said an overall gradual decrease in volcanic activities had prompted it to lower the alert level.
“However, [this] should not be interpreted that the unrest of the volcano has ceased,” it added.
At the peak of the alert, close to 50,000 people were being sheltered in public schools and other evacuation centers in Albay.
Homeward bound
The Joint Task Force Mayon (JTFM) started transporting the evacuees back to their homes Saturday morning.
The evacuees were given relief goods including 15 kilos of rice and P1,400 “cash for work” from President Macapagal-Arroyo through the Department of Social Welfare and Development.
A P15-million fund for farm rehabilitation (including two tractors from the Department of Agriculture) that was originally secured by the provincial government for upland areas is to be realigned to barangays around Mayon.
Capt. Razaleigh G. Bansawan, the JTFM spokesperson, said 25 military vehicles composed of 15 six-by-six trucks and 10 Korean-made KM450 vehicles had been dispatched to various shelters in Albay as of noon Saturday to transport the evacuees.
Roads within the 8-km extended danger zone were ordered opened for the passage of the evacuees.
The Bureau of Fire and Protection was also ordered to clean up the schools vacated by the evacuees in preparation for the resumption of classes on Monday.
The Phivolcs reminded the public that the 6-km permanent danger zone around Mayon and the 7-km extended danger zone on its southeast sector are off-limits to human activities because of “sudden explosions that may generate hazardous volcanic flows.”
As well, it reminded residents near the danger zones to be wary of “post-eruption activity, such as rock falls, pyroclastic flows and ash fallout, which can also occur any time due to the instability of lava deposited on steep slopes.”
Bansawan said checkpoints would be “repositioned” to prevent people, particularly farmers and tourists, from entering the restricted areas.
‘Miracle’
Vilma Ostria said she and her family had been staying with other Maninila residents at the evacuation center since Dec. 15, and constantly worrying over their household and farm.
“We want so much to go home,” the 45-year-old mother of seven told the Inquirer.
Ostria said she and her husband had been praying that their farm produce would not be wasted.
“Our tomatoes, which we will start harvesting by the end of this month, were spared by the ashfall. That’s a miracle, and that’s because of our strong faith in God,” Ostria said.
She said they had feared the loss of more than P50,000 in possible earnings from their half-hectare tomato farm, aside from the root crops that made up their daily food consumption along with rice and vegetables.
Ostria said no one would give them that kind of money if they lost the crops to thieves. “That’s why heads of families can’t just abandon their farms and stay in evacuation centers,” she said.
Widow Solidad Osila, 70, said she was happy to be told to prepare to decamp. “The sleepless nights are over. We sleep late at night here at the evacuation center, unlike at home where we sleep as early as 7 or 8 p.m.,” she said.
Like an island
Maninila is like an island whenever it is swamped by lahar (or volcanic mudflow) because it is surrounded by two rivers.
Mayon’s eruption in August 2006 caused no immediate deaths, but the following December, a passing typhoon unleashed an avalanche of lahar from its slopes that left about 1,000 dead.
Rosito Padua, a member of Maninila’s barangay council, said the disruption of the people’s livelihood was one of the worst effects of Mayon’s current unrest.
“We really don’t trust Mayon even if it is already slowing down, and as barangay officials, we will continue to be vigilant,” he said.
Padua said the evacuation had taken a toll on the earning capacity of the farmers, who should have made a number of harvests.
He said some farmers were able to make just one harvest, thus barely earning capital for the next planting season.
Padua recalled that during Mayon’s eruption in 1993, the residents of Maninila and of the adjacent Barangay Tandarora had to flee under a cloud of ash that billowed and settled on their rice farms.
“Thank God no one was killed,” he said.
Marieta Lacza, a mother of four who owns a sari-sari store in Maninila, brought her small business to the evacuation center in Barangay Travesia so that she could continue paying for her loan.
“Sales at the evacuation center are better because there are many buyers. But it is still the comfort of our home that we prefer because we can do other things, such as farming and other jobs.” said Lacza, 44.
Preemptive evacuation
The residents evacuated from the 6-km permanent danger zone totaled 12,803 (or 2,728 families) from 20 barangays in the cities of Ligao, Tabaco and Legazpi and the towns of Guinobatan, Camalig, Daraga, Sto. Domingo and Malilipot.
They were evacuated as early as the night of Dec. 14, when alert level three was declared.
The number rose to 47,285 (or 9,946 families) when the alert level was raised to four at 12 noon on Dec. 20, after 34,482 (or 7,218 additional families) were evacuated from the extended danger zones.
But many evacuees complained that the temporary shelters, mainly public schools, had inadequate facilities and food supplies.
Elba Bana, 60, said she was happy to go home.
But she added: “We are always afraid, especially when the rain is strong and there may be lahar. If there is strong rain, then we may be evacuated again.”
Governor Salceda said the preemptive evacuation had shown that the Philippines was well prepared in the case of a future eruption.
“We have proven already that we can easily bring [the people] back to the evacuation centers,” he said.
Prayer and plea
Salceda thanked everyone who had assisted the provincial government in the preemptive evacuation of residents.
“Thank you for the prayers,” he said, adding that it was the 12th time Albay had implemented a preemptive evacuation.
Salceda said a preemptive evacuation was “a community prayer in humility to God’s will and respect for nature, and similarly, a collective plea to preempt the disaster from materializing
Source: http://newsinfo.inquirer.net/inquirerheadlines/nation/view/20100102-245202/Definitely-over-for-now
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