Tuesday, June 10, 2014

Warming climates intensify greenhouse gas given out by oceans

Date:
June 8, 2014 - SCIENCE DAILY 
Source:
University of Edinburgh
Summary:
Rising global temperatures could increase the amount of carbon dioxide naturally released by the world's oceans, fueling further climate change, a study suggests. Scientists studied a 26,000-year-old sediment core to find out how the ocean's ability to take up atmospheric CO2 has changed over time, and found that when silicon was least abundant in ocean waters corresponded with relatively warm climates, low levels of atmospheric iron, and reduced CO2 uptake by the oceans' plankton.

Rising global temperatures could increase the amount of carbon dioxide naturally released by the world's oceans, fuelling further climate change, a study suggests.

Fresh insight into how the oceans can affect CO2 levels in the atmosphere shows that rising temperatures can indirectly increase the amount of the greenhouse gas emitted by the oceans.
Scientists studied a 26,000-year-old sediment core taken from the Gulf of California to find out how the ocean's ability to take up atmospheric CO2 has changed over time.
They tracked the abundance of the key elements silicon and iron in the fossils of tiny marine organisms, known as plankton, in the sediment core. Plankton absorb CO2 from the atmosphere at the ocean surface, and can lock away vast quantities of carbon.
Researchers found that those periods when silicon was least abundant in ocean waters corresponded with relatively warm climates, low levels of atmospheric iron, and reduced CO2 uptake by the oceans' plankton. Scientists had suspected that iron might have a role in enabling plankton to absorb CO2. However, this latest study shows that a lack of iron at the ocean surface can limit the effect of other key elements in helping plankton take up carbon.
This effect is magnified in the southern ocean and equatorial Pacific and coastal areas, which are known to play a crucial role in influencing levels of CO2 in the global atmosphere.
Researchers from the University of Edinburgh say their findings are the first to pinpoint the complex link between iron and other key marine elements involved in regulating atmospheric CO2 by the oceans. Their findings were verified with a global calculation for all oceans. The study, published in Nature Geoscience, was supported by Scottish Alliance for Geoscience Environment Society and the Natural Environment Research Council.
Dr Laetitia Pichevin, of the University of Edinburgh's School of GeoSciences, who led the study, said: "Iron is known to be a key nutrient for plankton, but we were surprised by the many ways in which iron affects the CO2 given off by the oceans. If warming climates lower iron levels at the sea surface, as occurred in the past, this is bad news for the environment."
Story Source:
The above story is based on materials provided by University of Edinburgh. Note: Materials may be edited for content and length.
Journal Reference:
  1. L. E. Pichevin, R. S. Ganeshram, W. Geibert, R. Thunell, R. Hinton. Silica burial enhanced by iron limitation in oceanic upwelling margins. Nature Geoscience, 2014; DOI: 10.1038/ngeo2181
Cite This Page:
University of Edinburgh. "Warming climates intensify greenhouse gas given out by oceans." ScienceDaily. ScienceDaily, 8 June 2014. .
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Streaming video more 'green' than DVDs? Billions of kilograms of carbon dioxide could be saved by scrapping discs, study shows

Date:
May 28, 2014 - SCIENCE DAILY
Source:
Institute of Physics
Summary:
A new study has shown that streaming can be much better for the environment, requiring less energy and emitting less carbon dioxide, than some traditional methods of DVD renting, buying and viewing. The study's authors cite modern devices such as laptops and tablets as the reason for this improvement, as they are much more efficient than older, energy-sapping DVD players.

A trip down to the local DVD store has slowly become a thing of the past thanks to the rise of video streaming services, which allow viewers to indulge in back-to-back episodes of hit TV series like House of Cards and Breaking Bad at the click of a button.

Now, a new study has shown that streaming can be much better for the environment, requiring less energy and emitting less carbon dioxide (CO2), than some traditional methods of DVD renting, buying and viewing.

The researchers, who have published their study today, 29 May, in IOP Publishing's journal Environmental Research Letters, cite modern devices such as laptops and tablets as the reason for this improvement, as they are much more efficient than older, energy-sapping DVD players.
Furthermore, the driving that is required to go and buy, or rent, DVDs makes this method much more energy- and carbon-intensive.
A significant proportion of the energy consumption and carbon emissions for streaming comes from the transmission of data, which increases drastically when more complex, high-definition content is streamed.
In their study, the researchers, from Lawrence Berkley National Laboratory and Northwestern University, estimated that if all DVD viewing in the US was shifted to streaming services in 2011, around 2 billion kg of CO2 emissions could have been avoided and around 30 petajoules (PJ) of energy saved -- the equivalent of the amount of electricity needed to meet the demands of 200,000 US households.
They estimated that in 2011, 192 PJ of energy was used, and 10.4 billion kg of CO2 emitted, for all methods of DVD consumption and streaming in the US.
From this, they calculated that one hour of video streaming requires 7.9 megajoules (MJ) of energy, compared to as much as 12 MJ for traditional DVD viewing, and emits 0.4 kg of CO2, compared to as much as 0.71 kg of CO2 for DVD viewing.
To arrive at their results, the researchers compared video streaming with four different types of DVD consumerism: DVDs that are rented from online mailers; DVDs that are rented from a store; DVDs that are purchased online; and DVDs that are bought from a store.
Video streaming was limited to TV and movies and did not include shorter videos that are streamed online through YouTube etc.
They found that video streaming and the online rental of DVDs required similar amounts of energy; however, the renting and purchasing of DVDs from a store were much more energy intensive, due to the impact of driving.
  • stimated at 20%, 77%, and 3%, respectively
Story Source:
The above story is based on materials provided by Institute of Physics. Note: Materials may be edited for content and length.
Journal Reference:
  1. Arman Shehabi, Ben Walker, Eric Masanet. The energy and greenhouse-gas implications of internet video streaming in the United States. Environmental Research Letters, 2014; 9 (5): 054007 DOI: 10.1088/1748-9326/9/5/054007
  2. Cite This Page:
    Institute of Physics. "Streaming video more 'green' than DVDs? Billions of kilograms of carbon dioxide could be saved by scrapping discs, study shows." ScienceDaily. ScienceDaily, 28 May 2014. .
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Drop in global malnutrition depends on agricultural productivity, climate change

Date:
May 29, 2014 -SCIENCE DAILY 
Source:
Purdue University
Summary:
Global malnutrition could fall 84 percent by the year 2050 as incomes in developing countries grow -- but only if agricultural productivity continues to improve and climate change does not severely damage agriculture, researchers say. According to the researchers' models, income growth coupled with projected increases in agricultural productivity could raise more than half a billion people out of extreme hunger by mid-century.

Global malnutrition could fall 84 percent by the year 2050 as incomes in developing countries grow -- but only if agricultural productivity continues to improve and climate change does not severely damage agriculture, Purdue University researchers say.

"The prevalence and severity of global malnutrition could drop significantly by 2050, particularly in the poorest regions of the world," said Thomas Hertel, Distinguished Professor of Agricultural Economics. "But if productivity does not grow, global malnutrition will worsen even if incomes increase. Climate change also adds a good deal of uncertainty to these projections."
Hertel and doctoral student Uris Baldos developed a combination of economic models -- one that captures the main drivers of crop supply and demand and another that assesses food security based on caloric consumption -- to predict how global food security from 2006 to 2050 could be affected by changes in population, income, bioenergy, agricultural productivity and climate.
According to the models, income growth coupled with projected increases in agricultural productivity could raise more than half a billion people out of extreme hunger by mid-century.
Income is also set to eclipse population as the dominant driver of food security, a "historical first," said Baldos.
"We expect that the population driver will diminish relative to per capita income in the coming decades, especially in the developing world," he said.
Growth in income will allow people to increase the amount of food they consume and "upgrade" their diets by adding more meat and processed foods to staples such as crops and starches. The shift toward a diet higher in calories and richer in protein could lift many in hunger-stricken regions such as sub-Saharan Africa, South Asia, China and Mongolia above the malnutrition line.
Globally, the volume of food consumed per capita could increase by about 31 percent. In developing regions with strong growth in income and population, consumption could rise by about 56 to 75 percent.
But these projections depend heavily on corresponding increases in agricultural productivity, Hertel said. Productivity is a measure of crop yields relative to the inputs used in producing them such as land, labor and fertilizers. Increased global productivity improved the availability of food over the last 50 years, but this trend must continue between now and 2050 to buttress food security.
"There is a clear lin. "Boosting productivity tends to lower food prices, and declines in the cost of food in turn can allok between productivity growth in agriculture and the number of malnourished people," Hertel saidw for better nutrition. Income growth alone will not be enough to solve the malnutrition problem."
Historically, agricultural productivity has been driven by investments in agricultural research and development. The researchers said improvements in food security depend on increasing research spending, especially over the next two decades.
"The decisions we make now about funding for agricultural research will have implications for a number of malnourished people in 2050," Hertel said. "If agricultural productivity stagnates, there will be far more malnourished people in the future, particularly in regions where chronic hunger is already present."
The researchers also cautioned that the impacts of a changing climate on crop yields remain uncertain.
Rising temperatures could extend the growing season in northern latitudes, and an increase in carbon dioxide in the atmosphere could benefit some crops by improving water efficiency. But climate change is complicated, Hertel said.
"Up to 2050, there could be some pluses for agriculture," he said. "But in the longer run, adverse temperatures will likely become overwhelming, and rising carbon dioxide concentrations won't help after a certain point. Eventually, you drop off a cliff."
The models show that climate change is a less influential driver of global food security than income, population and productivity -- but it could still pose a significant risk to the nutrition levels of people living in the world's poorest regions, Baldos said.
"People living in the most hunger-stricken areas will be the most vulnerable to climate change."
Story Source:
The above story is based on materials provided by Purdue University. The original article was written by Natalie van Hoose. Note: Materials may be edited for content and length.
Journal Reference:
  1. Uris Lantz C. Baldos, Thomas W. Hertel. Global food security in 2050: the role of agricultural productivity and climate change. Australian Journal of Agricultural and Resource Economics, 2014; DOI: 10.1111/1467-8489.12048
Cite This Page:
Purdue University. "Drop in global malnutrition depends on agricultural productivity, climate change." ScienceDaily. ScienceDaily, 29 May 2014. .
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A more Earth-friendly way to make bright white cotton fabrics

Date:
May 28, 2014 -SCIENCE DAILY 
Source:
American Chemical Society
Summary:
With a growing number of consumers demanding more Earth-friendly practices from the fashion world, scientists are developing new ways to produce textiles that could help meet rising expectations. One such method can dramatically reduce the amount of energy it takes to bleach cotton while improving the quality of the popular material.

With a growing number of consumers demanding more Earth-friendly practices from the fashion world, scientists are developing new ways to produce textiles that could help meet rising expectations. They report in the ACS journal Industrial & Engineering Chemistry Researchone such method that can dramatically reduce the amount of energy it takes to bleach cotton while improving the quality of the popular material.

Quan Zu and colleagues point out that the cotton industry's current whitening techniques require bleaching the natural fiber at very high temperatures with hydrogen peroxide. Although this method results in the bright white material consumers have grown so fond of, it also lowers the quality of the material and takes a lot of energy to carry out. Multiply that by the 7.3 billion pounds of cotton produced in the U.S. alone, and the energy needs soar. To cut down on the energy the textile industry uses to make cotton, Zu's team targeted its efforts toward lowering the bleaching technique's high temperatures.
They developed a novel compound that, when used with hydrogen peroxide, drops the bleaching temperature down to 140 degrees Fahrenheit from 200 degrees. The authors estimated that 60 degree difference would result in a process requiring less than half the energy as the commercial technique. It also produced less wastewater, improved the weight of the material and performed its original function -- whitening the cotton. Since many materials destined to become clothing eventually take on various hues, the scientists also tested dyes and found the cotton bleached at the lower temperature could be made just as vibrant as its high-heat counterpart. They successfully showed the treatment's effectiveness on knitted cotton fabric in commercial scale trials.
Story Source:
The above story is based on materials provided by American Chemical Society.Note: Materials may be edited for content and length.
ournal Reference:
  1. Shenxi Wang, Shiqi Li, Quan Zhu, Charles Q. Yang. A Novel Low Temperature Approach for Simultaneous Scouring and Bleaching of Knitted Cotton Fabric at 60°C. Industrial & Engineering Chemistry Research, 2014; 140517132116006 DOI: 10.1021/ie500062f
Cite This Page:
American Chemical Society. "A more Earth-friendly way to make bright white cotton fabrics." ScienceDaily. ScienceDaily, 28 May 2014. .
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Climate change now a mainstream part of city planning: Global survey

Date:
May 29, 2014
Source:
Massachusetts Institute of Technology
Summary:
Cities are planning for climate change, research shows, but are still searching for links to economic growth. The report underscores the extent to which city leaders recognize climate change as a major challenge -- even as they are trying to figure out how their responses can create jobs, growth, and cost savings in areas ranging from cities' transportation networks to their distribution of businesses.

An increasing number of cities around the world now include preparations for climate change in their basic urban planning -- but only a small portion of them have been able to make such plans part of their economic development priorities, according to a unique global survey of cities released today.The Urban Climate Change Governance Survey (UCGS), based on responses from 350 cities worldwide, underscores the extent to which city leaders recognize climate change as a major challenge -- even as they are trying to figure out how their responses can create jobs, growth, and cost savings in areas ranging from cities' transportation networks to their distribution of businesses.
"Climate change isn't an isolated issue," says Alexander Aylett, a postdoc in MIT's Department of Urban Studies and Planning (DUSP), and the lead author of today's report. "It has large implications for all other aspects of urban life. What we are seeing is cities starting to build it into the DNA of how they approach urban planning."
According to the findings, 75 percent of cities worldwide now tackle climate-change issues as a mainstream part of their planning, and 73 percent of cities are attempting both climate mitigation and climate adaptation -- that is, they are trying both to reduce emissions of greenhouse gases and to adapt to long-term changes that are already in motion. But only 21 percent of cities report tangible connections between the response to climate change and achieving other local development goals.
Aylett calls it a "cliché" that environmental and economic progress cannot coexist, citing a number of cities where jobs and growth have derived from climate-change efforts. Portland, Ore., he observes, developed incentives, training, and regulations to help sustainable construction firms grow, while a pilot program called Clean Energy Works Portland employed 400 workers to reduce home energy use, reducing carbon emissions by 1,400 metric tons annually.
Urban planners in Alberta, as Aylett notes, have studied the cost savings associated with limiting metropolitan sprawl and concluded that denser development could save $11 billion in capital costs over the next 60 years, and $130 million in annual maintenance. But most cities, he suggests, have simply not yet identified ways to link climate planning and economic development in the first place.
"It isn't so much that it's hard to reconcile economic and environmental priorities," Aylett says. "It's that we're not trying."
Regional differences remain
The new report is a companion to a survey conducted in 2012. This year's results revealed continuing regional disparities in urban climate planning. Compared with the global average of 75 percent, U.S. cities lag in planning for both mitigation and adaptation, with just 58 percent of cities addressing both. This echoes the 2012 survey, which revealed that a smaller portion of U.S. cities were doing basic climate-change planning, compared with those in other regions -- 59 percent in the U.S., for instance, compared with 95 percent in Latin America.
Globally, 63 percent of cities say they have between one and five employees dedicated to climate-change planning; North American cities are most likely to have just one staff member focused on the topic. As the report's executive summary notes, "A lack of funding to hire sufficient staff to work on climate change is a significant challenge for 67 percent of cities."
On a different note, about 85 percent of cities have conducted an inventory of local greenhouse-gas emissions, and 15 percent, as part of that effort, have tried to track the emissions that stem from goods and services consumed within that city. As Aylett points out, "Beginning to address these upstream emissions is crucial if cities are really going to help bring down global emissions."
The results also reveal that local industries and businesses are relatively disengaged with urban responses to climate change: About 25 percent of cities say that local businesses have been crucial to creating and implementing their climate mitigation plans, whereas 48 percent of cities report that local civil-society groups, such as nonprofits or other organizations, have been involved in climate planning.
The full report can be found at www.urbanclimatesurvey.com.
Story Source:
The above story is based on materials provided by Massachusetts Institute of Technology. The original article was written by Peter Dizikes. Note: Materials may be edited for content and length.
Cite This Page:
Massachusetts Institute of Technology. "Climate change now a mainstream part of city planning: Global survey." ScienceDaily. ScienceDaily, 29 May 2014. .
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Ecosystem services: Looking forward to mid-century

Date:
May 29, 2014
Source:
University of California - Santa Barbara
Summary:
As population grows, society needs more -- more energy, more food, more paper, more housing, more of nearly everything. Meeting those needs can lead to changes in how land is used. Native grasslands, forests and wetlands may be converted into croplands, tree plantations, residential areas and commercial developments. Those conversions can, in turn, diminish the health of natural ecosystems and their ability to provide an array of valuable services, such as clean air and water, wildlife and opportunities for recreation, to name a few.

As  population grows, society needs more -- more energy, more food, more paper, more housing, more of nearly everything. Meeting those needs can lead to changes in how land is used.

Native grasslands, forests and wetlands may be converted into croplands, tree plantations, residential areas and commercial developments. Those conversions can, in turn, diminish the health of natural ecosystems and their ability to provide an array of valuable services, such as clean air and water, wildlife and opportunities for recreation, to name a few.
In two papers published in the Proceedings of the National Academy of Sciences, UC Santa Barbara's Andrew Plantinga addresses how to strike a balance between providing for humanity's growing needs and preserving the natural systems that make it possible to meet those needs. In one paper, Plantinga, a professor at the Bren School of Environmental Science & Management, and colleagues model the future of land-use change in the United States under various scenarios and possible effects on the provision of some important ecosystem services. In a related publication, the researchers develop incentive structures to best encourage landowners to provide ecosystem services.
The work of the first paper explains a new land-use model for the contiguous U.S., which forecasts trends from 2001-2051 using two baseline scenarios and three policy alternatives designed to encourage forest cover and the preservation of natural landscapes as well as the reduction of urban expansion.
"The 1990s Trend" baseline scenario assumes land-use trends will continue as they did during the 1990s, resulting in less cropland, pasture and rangeland and more forests and urbanization. The "High Crop Demand" model accounts for significant growth in the demand for agricultural commodities as well as related pressures to expand agricultural lands. The researchers used these scenarios as alternative baselines against which they analyzed the effects of the three alternative land-use policies: forest incentives, natural habitats and urban containment.
The first policy provides incentives for reduced deforestation and for afforestation -- moving land into forest, whether by converting cropland to natural forest or by establishing commercial timber operations. The second provides incentives for conserving natural habitats, and the third restricts urban land expansion.
The key takeaway, Plantinga explained, is that there are tradeoffs for every policy regardless of which baseline scenario is applied. "Projected land-use changes by 2051 will likely enhance the provision of some ecosystem services and decrease the provision of others," he said. In this application, ecosystem services are defined as the goods and services provided by nature that are of value to people.
In the end, land use is not the most important component, according to Plantinga. "The point is to identify which types of ecosystem services are provided as land use changes," he concluded. "Food and carbon sequestrations are fine and may even rise under the various scenarios, but you may need strong incentives to limit declines in the provision of other ecosystem services."
Incentive Structures for Landowners
Plantinga collaborated with many of the same co-authors on another paper which identifies the best auction structure for securing ecosystem services, particularly those provided by private landowners. Building on established auction theory, the paper breaks new ground in structuring an auction that addresses three key challenges to inducing private landowners to provide optimal levels of ecosystem services.
These include the spatial component of ecosystem services. For example, adjoining parcels of land may be more valuable from the perspective of providing habitat than three fragmented parcels adding up to the same size. Additional challenges include asymmetric information, which refers to the fact that landowners know the opportunity cost of their land while the government agency does not, and the requirement to use voluntary incentives or what are often called payments for ecosystem services.
Because forests, clean rivers, climate regulation and other ecosystem services are freely available to everyone, landowners often receive nothing for actions they take on their own land that contribute to the pool of ecosystem services. Those services may be underprovided due to a lack of price incentives for private activities taken for the public good.
The researchers designed an auction that would elicit the optimal enrollment of lands -- and the optimal provision of ecosystem services -- in situations defined by asymmetric information and spatially dependent benefits.
Story Source:
The above story is based on materials provided by University of California - Santa Barbara. The original article was written by James Badham. Note: Materials may be edited for content and length.
Journal Reference:
  1. J. J. Lawler, D. J. Lewis, E. Nelson, A. J. Plantinga, S. Polasky, J. C. Withey, D. P. Helmers, S. Martinuzzi, D. Pennington, V. C. Radeloff. Projected land-use change impacts on ecosystem services in the United States. Proceedings of the National Academy of Sciences, 2014; 111 (20): 7492 DOI:10.1073/pnas.1405557111
Cite This Page:
University of California - Santa Barbara. "Ecosystem services: Looking forward to mid-century." ScienceDaily. ScienceDaily, 29 May 2014. .
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New global maps of livestock distribution

Date:
May 30, 2014 - SCIENCE DAILY 
Source:
Libre de Bruxelles, Université
Summary:
New global maps of livestock distribution have been established by an international team of researchers. This study should help to measure the socio-economic, public health and environmental impacts of livestock and poultry, worldwide. The evaluation of multiple socio-economic, environmental and public health around the livestock sector requires accurate accessible and comprehensive spatial data on the distribution and abundance of livestock.

Led  by Marius Gilbert -- Interfaculty School of Bioengineering , Université libre de Bruxelles -- and Tim Robinson (ILRI, Kenya), an international researcher team established new global maps of livestock distribution. This study should help to measure the socio-economic, public health and environmental impacts of livestock and poultry, worldwide .

The evaluation of multiple socio- economic, environmental and public health around the livestock sector requires accurate accessible and comprehensive spatial data on the distribution and abundance of livestock.
A team of researchers led by Marius Gilbert, Research Associate of the FNRS -- Laboratory of Biological Control and Spatial Ecology ( LUBIES ) , Interfaculty School of Bioengineering ( EIB , Université libre de Bruxelles) and Tim Robinson (International Livestock Research Institute, Nairobi, Kenya)publishes this week in PLoS ONE new global maps of livestock and poultry.
The map data that accompany this publication are distributed in open access under " Creative Commons " license, and can be viewed or downloaded via the platform "Livestock Geo- wiki" (http://www.livestock.geo-wiki.org / ). This platform will also be used to distribute updates that will regularly be generated as new census data becomes available.
These data should help quantifying different types of impact of the livestock sector and contribute to the development of policies to promote a safe, sustainable and equitable sector development in the coming decades .
Livestock now represents the largest biomass among terrestrial vertebrates, ahead of that of the human population and far ahead of that of wild animals. In Belgium, for example, the density of pigs and poultry per km2 is one of the highest in the world . At the global scale, the growth in demand for livestock products has never been greater than today.
In developing countries, production of milk and meat have grown, from 1970 to today, at an average yearly rates of 5.1 and 3.6 percent respectively and the Food and Agriculture Organization (FAO) forecasts that the demand for these commodities will increase by 73 % and 58 % between 2010 and 2030.
The growing livestock sector places ever greater pressure on our natural resources and the environment. It contributes significantly to global environmental change with a recently estimated 14.5% of anthropogenic greenhouse gas emissions attributable to the sector, as well as through environmental problems associated with manure management and disruption of the nitrogen cycle in the soil, water and air.
Also of concern are the public health implications of livestock intensification. The widespread use of antibiotics in livestock, for preventive or curative purposes or as growth promoters directly contributes to the increasing prevalence of resistant strains of bacteria to antibiotics both at local and global levels . In many countries, the pressure on the land available for agriculture and livestock farmers pushes people and their livestock into ever-close proximity to natural areas that constitute the habitat of wildlife, which increases the chances of emergence and spread of zoonotic infectious agents originating in wild animals. Finally, it is estimated today that one in three human in the world -- 1.46 billion -- is obese or overweight, a problem to which of over-consumption of processed products of animal origin contributes significantly .
But livestock are also a source of livelihoods and food security for almost a billion people. As well as the actual economic benefits that livestock already confers on the economies and rural development in poor countries , and potential improvements in food security and nutrition, some 766 million poor farmers living with an income < $ 2 U.S. per day could directly benefit from improvements in this sector. This is particularly the case in mixed farming systems that combine crops and livestock , where livestock serves many functions in terms of animal traction and renewal of soil fertility.
Moreover , livestock grazing systems are also used to produce meat and milk in areas unsuitable for crop production. Today, nearly 800 million people are affected by food insecurity and the number of children affected by stunting due to malnutrition is estimated at 165 million. There has never been a greater need to ensure equitable, efficient and sustainable food production; the livestock sector plays an essential role in achieving this objective . The new global mapping of livestock and poultry will facilitate the assessment of impacts of livestock and to contribute to the development of appropriate policies.
This study is the result of a partnership between the Laboratory of Biological Control and Spatial Ecology (ULB , LUBIES ) , the International Livestock Research Institute ( ILRI , Nairobi , Kenya) , the Food and Agricultural Organization of the united Nations (FAO , Rome, Italy ) and the University of Oxford (United Kingdom). The platform release has been established by our collaborators at the International Institute for Applied Systems Analysis (IIASA) .
Story Source:
The above story is based on materials provided by Libre de Bruxelles, Université.Note: Materials may be edited for content and length.
Journal Reference:
  1. Timothy P. Robinson, G. R. William Wint, Giulia Conchedda, Thomas P. Van Boeckel, Valentina Ercoli, Elisa Palamara, Giuseppina Cinardi, Laura D'Aietti, Simon I. Hay, Marius Gilbert. Mapping the Global Distribution of Livestock.PLoS ONE, 2014; 9 (5): e96084 DOI: 10.1371/journal.pone.0096084
Cite This Page:
Libre de Bruxelles, Université. "New global maps of livestock distribution." ScienceDaily. ScienceDaily, 30 May 2014. .
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New evidence links air pollution to autism, schizophrenia

 Date:
June 5, 2014 - SCIENCE DAILY 
Source:
University of Rochester Medical Center
Summary:
A new study describes how exposure to air pollution early in life produces harmful changes in the brains of mice, including an enlargement of part of the brain that is seen in humans who have autism and schizophrenia. The mice performed poorly in tests of short-term memory, learning ability, and impulsivity. Study authors say the findings are very suggestive that air pollution may play a role in autism, as well as in other neurodevelopmental disorders.

A new study published in the journal Environmental Health Perspectivesdescribes how exposure to air pollution early in life produces harmful changes in the brains of mice, including an enlargement of part of the brain that is seen in humans who have autism and schizophrenia.

As in autism and schizophrenia, the changes occurred predominately in males. The mice also performed poorly in tests of short-term memory, learning ability, and impulsivity.
The new findings are consistent with several recent studies that have shown a link between air pollution and autism in children. Most notably, a 2013 study in JAMA Psychiatry reported that children who lived in areas with high levels of traffic-related air pollution during their first year of life were three times as likely to develop autism. "Our findings add to the growing body of evidence that air pollution may play a role in autism, as well as in other neurodevelopmental disorders," said Deborah Cory-Slechta, Ph.D., professor of Environmental Medicine at the University of Rochester and lead author of the study.
In three sets of experiments, Cory-Slechta and her colleagues exposed mice to levels of air pollution typically found in mid-sized U.S. cities during rush hour. The exposures were conducted during the first two weeks after birth, a critical time in the brain's development. The mice were exposed to polluted air for four hours each day for two four-day periods.
In one group of mice, the brains were examined 24 hours after the final pollution exposure. In all of those mice, inflammation was rampant throughout the brain, and the lateral ventricles -- chambers on each side of the brain that contain cerebrospinal fluid -- were enlarged two-to-three times their normal size.
"When we looked closely at the ventricles, we could see that the white matter that normally surrounds them hadn't fully developed," said Cory-Slechta. "It appears that inflammation had damaged those brain cells and prevented that region of the brain from developing, and the ventricles simply expanded to fill the space."
The problems were also observed in a second group of mice 40 days after exposure and in another group 270 days after exposure, indicating that the damage to the brain was permanent. Brains of mice in all three groups also had elevated levels of glutamate, a neurotransmitter, which is also seen in humans with autism and schizophrenia.
Most air pollution is made up mainly of carbon particles that are produced when fuel is burned by power plants, factories, and cars. For decades, research on the health effects of air pollution has focused on the part of the body where its effects are most obvious -- the lungs. That research began to show that different-sized particles produce different effects. Larger particles -- the ones regulated by the Environmental Protection Agency (EPA) -- are actually the least harmful because they are coughed up and expelled. But many researchers believe that smaller particles known as ultrafine particles -- which are not regulated by the EPA -- are more dangerous, because they are small enough to travel deep into the lungs and be absorbed into the bloodstream, where they can produce toxic effects throughout the body.
That assumption led Cory-Slechta to design a set of experiments that would show whether ultrafine particles have a damaging effect on effect on the brain, and if so, to reveal the mechanism by which they inflict harm. Her study published today is the first scientific work to do both.
"I think these findings are going to raise new questions about whether the current regulatory standards for air quality are sufficient to protect our children," said Cory-Slechta.
Story Source:
The above story is based on materials provided by University of Rochester Medical Center. Note: Materials may be edited for content and length.
Journal Reference:
  1. Joshua L. Allen, Xiufang Liu, Sean Pelkowski, Brian Palmer, Katherine Conrad, Günter Oberdörster, Douglas Weston, Margot Mayer-Pröschel, Deborah A. Cory-Slechta. Early Postnatal Exposure to Ultrafine Particulate Matter Air Pollution: Persistent Ventriculomegaly, Neurochemical Disruption, and Glial Activation Preferentially in Male Mice. Environmental Health Perspectives, 2014; DOI: 10.1289/ehp.1307984
Cite This Page:
University of Rochester Medical Center. "New evidence links air pollution to autism, schizophrenia." ScienceDaily. ScienceDaily, 5 June 2014. .


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Saving trees in tropics could cut emissions by one-fifth, study shows

Date:
June 6, 2014 - SCIENCE DAILY
Source:
University of Edinburgh
Summary:
Reducing deforestation in the tropics would significantly cut the amount of carbon dioxide emitted into the atmosphere -- by as much as one-fifth -- research shows. In the first study of its kind, scientists have calculated the amount of carbon absorbed by the world's tropical forests and the amounts of greenhouse gas emissions created by loss of trees, as a result of human activity.

In the first study of its kind, scientists have calculated the amount of carbon absorbed by the world's tropical forests and the amounts of greenhouse gas emissions created by loss of trees, as a result of human activity.
They found that tropical forests absorb almost two billion tonnes of carbon each year, equivalent to one-fifth of the world's carbon emissions, by storing it in their bark, leaves and soil. However, an equivalent amount is lost through logging, clearing of land for grazing, and growing biofuel crops such as palm oil, soya bean and sugar. Peat fires in forests add significantly to the greenhouse gas emissions.
Researchers estimate that if all human-related deforestation of the tropics were to stop, the forests could absorb more carbon than at present, equivalent to one-fifth of global emissions.
Researchers say carbon emissions from tropical forests will increase as the climate warms, as rising temperatures accelerate the decay of dead plants and trees, giving off more CO2. Global temperatures are forecast to rise by two degrees by the year 2099, which is predicted to increase annual carbon emissions from the forest by three-quarters of a billion tonnes.
Scientists from the Universities of Edinburgh and Leeds analysed data from multiple previous studies, including satellite studies, to determine the amount of carbon absorbed and emitted by the world's tropical forests in South and Central America, equatorial Africa and Asia.
Their study, published in Global Change Biology, was supported by the Natural Environment Research Council.
Professor John Grace of the University of Edinburgh's School of GeoSciences, who led the study, said: "If we limit human activity in the tropical forests of the world, this could play a valuable role in helping to curb the rise in carbon dioxide in the atmosphere. Preventing further losses of carbon from our tropical forests must remain a high priority."
Story Source:
The above story is based on materials provided by University of Edinburgh. Note: Materials may be edited for content and length.
Journal Reference:
  1. John Grace, Edward Mitchard, Emanuel Gloor. Perturbations in the carbon budget of the tropics. Global Change Biology, 2014; DOI: 10.1111/gcb.12600
Cite This Page:
University of Edinburgh. "Saving trees in tropics could cut emissions by one-fifth, study shows." ScienceDaily. ScienceDaily, 6 June 2014. .
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Saturday, June 7, 2014

Close-up of coral bleaching event

Date:
June 3, 2014 - SCIENCE DAILY
Source:
University of Georgia
Summary:
Ecologists have shed light on exactly what happens to coral during periods of excessively high water temperatures. Their study documents a coral bleaching event in the Caribbean in minute detail and sheds light on how it changed a coral's community of algae -- a change that could have long-term consequences for coral health, as bleaching is predicted to occur more frequently in the future.

New research by University of Georgia ecologists sheds light on exactly what happens to coral during periods of excessively high water temperatures. Their study, published in the journal Limnology and Oceanography, documents a coral bleaching event in the Caribbean in minute detail and sheds light on how it changed a coral's community of algae—a change that could have long-term consequences for coral health, as bleaching is predicted to occur more frequently in the future.

Millions of people around the world depend on coral reefs and the services they provide. While coral reefs make up less than 0.1 percent of the sea floor, they serve as habitats for about 25 percent to 35 percent of all the oceans' fishes, roughly 500 million people worldwide rely on them as a source of protein and for coastal protection, and they are responsible for billions of dollars in tourism and fisheries revenue.
Corals, in turn, depend upon single-celled algae that inhabit them, providing most of their food and giving them their color. But many species of these algae are highly sensitive to temperature, and are unable to survive as ocean waters warm. The coral can expel these algae when the water temperature grows too high, a phenomenon known as coral bleaching.
Lead author Dustin Kemp, a postdoctoral associate in the UGA Odum School of Ecology, had the opportunity to study a bleaching event while conducting research at a reef off Puerto Morelos, Mexico. He and his colleagues had been working there since 2007, taking samples seasonally from six colonies of Orbicella faveolata, also known as mountainous star coral, and their associated symbiotic algae.
Orbicella is the major reef-building coral in most of the Caribbean, but although common, it has an unusual trait. While most species of coral associate with just one dominant type of symbiotic algae, O. faveolata is able to associate with up to four co-dominant types at once—some of which are heat-tolerant and some of which are not—making it a particularly interesting coral to study.
In October 2009, the researchers' sampling trip coincided with a period of unusually high temperatures, allowing them the rare opportunity to collect samples while a bleaching event was taking place.
"We were able to follow this coral at a very high precision and document how diverse assemblages of symbiotic algae are differently affected by the bleaching phenomenon," Kemp said. "This was probably the first study ever to look at it under natural conditions this closely."
Kemp took hundreds of samples approximately every 12 inches along established transects—a narrow section where measurements are taken—across all six coral colonies. He made sure to include samples from areas that appeared bleached as well as from those that still retained color. Because they had been collecting at the site for two years, and continued collecting after this event, the researchers were able to compare the communities of symbiotic algae before, during and after bleaching.
They observed that before the bleaching event, these particular corals contained three different types of algae, two of which were somewhat tolerant of the warm-water bleaching perturbation.
During the bleaching event, heat-sensitive algae were found to be much less prevalent while the heat-tolerant algae remained. Two months later, heat-tolerant algae had taken over the parts of the coral formerly occupied by the heat-sensitive algae.
"The corals didn't die after this bleaching event, they recovered—and that's good, that's important—but there could be potential tradeoffs associated with the shift to heat-tolerant algae," said Kemp, adding that, for example, some heat-tolerant algae may provide less food than those they might replace. "That question of tradeoffs is what we're working on now."
Kemp is currently conducting research at reefs in the Caribbean and Pacific, looking at how heat-tolerant algae affect corals in areas where corals have been documented to have stable, long-term associations with heat-tolerant algae.
"In the Caribbean, we've lost 80 percent of the corals just in my lifetime," Kemp said. "We know that increased ocean temperatures are one of the major threats to coral reefs worldwide. So understanding coral-algae dynamics, and how different algae can handle increased temperature, is important to see how the whole ecosystem will be affected by this environmental perturbation."
Story Source:
The above story is based on materials provided by University of Georgia. The original article was written by Beth Gavrilles. Note: Materials may be edited for content and length.
Cite This Page:
University of Georgia. "Close-up of coral bleaching event." ScienceDaily. ScienceDaily, 3 June 2014. .

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