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Animals And Social Distancing | Earth Wise

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As the spread of COVID-19 continues throughout the U.S. and around the world, health officials continue to ask people to keep physical space between themselves and others outside their homes.  It’s an important and effective way to slow down and prevent the spread of disease. 

But it’s not just humans who can benefit from social distancing.  It turns out that animals can, too.

Microorganisms living on or inside our bodies are important for both our health and for the development of disease.  Researchers from the University of Texas at San Antonio have found evidence for the importance of social distancing to minimize the spread of microbes among individuals.   The researchers studied wild monkeys to find out what role diet, genetics, social groupings, and distance in a social network play when it comes to the microbes found inside the gut.  The gut microbiome refers to all the microorganisms living in the digestive tract. 

The research team studied the fecal matter of 45 female colobus monkeys that congregated in eight different social groups in a small forest in Ghana.  The researchers observed major differences in gut microbiomes between the eight social groups.  But individual monkeys from different groups that were more closely connected to the population’s social network had more similar gut microbiomes.  The findings, recently published in the journal Animal Behaviour, indicate that microbes may be transmitted between monkeys during occasional encounters with other monkeys from different social groups.

Learning how microorganisms pass among monkeys can help researchers understand how diseases spread.  Understanding how diseases spread can help guide decision making during this pandemic and any future disease outbreaks. 

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Even animals benefit from social distance to prevent disease, research shows

Photo, posted January 10, 2007, courtesy of Silke Baron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Charleston Dry | Earth Wise

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Charleston, South Carolina is visited by millions of tourists each year.  The town is a glimpse into the past, showcasing antebellum mansions, row houses, historic African American churches and scenic harbor views from a Civil War-era promenade.

Charleston is also visited more and more by water from rising seas and increasingly powerful storms.  The city is essentially drowning in slow motion and may soon face an existential threat to its survival.

Charleston has a harbor and three rivers and water from all these sources leaks in at every bend and curve, fills streets, disrupts businesses, and rushes into homes during storms.  Million-dollar antebellum mansions, built on spongy marsh and old tidal creeks, flood repeatedly.

City officials have endorsed a plan by the U.S. Army Corps of Engineers to wall off the historic downtown with an 8-mile-long seawall that would cost nearly $2 billion.  The proposed barricade is just one of many proposed projects to build seawalls, surge gates, levees, and other barriers to defend U.S. coastal cities in an era of rising seas and climate-fueled floods and storms.  A proposed flood wall in Miami would cost federal taxpayers $8 billion.

Researchers generally agree that sea levels are likely to rise by at least 3 feet by the end of the century.  Some experts believe the rise will be much greater.  So, a key question is whether these barriers will actually keep out the water.  Critics of many of the proposed solutions contend that they are doomed to fail.

Flooding has caused nearly $1 trillion worth of damage along the East and Gulf coasts over the past 40 years.  And things are almost certain to get worse in Charleston and other coastal cities.

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Fortress Charleston: Will Walling Off the City Hold Back the Waters?

Photo, posted October 7, 2015, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic From Algae | Earth Wise

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Many researchers consider algae to be one of the best renewable resources for replacing fossil fuels and even as a food source.  The green microalgae Nannochloropsis salina is already a common source of omega-3 fatty acids that are sold as dietary supplements.  As a result, that algae strain is already grown on a large scale for the production of omega-3 products.

A group of researchers at UC San Diego has developed a way to make use of the waste stream from that production to create plastics and other useful products.  Currently, when the algae is processed to extract the omega-3 oil, leftover oils comprising more than 70% of the starting material are either thrown away or burned. 

The UCSD team has developed a process to purify and convert this waste stream into azelaic acid, which is a building block for flexible polyurethanes.   These materials have all kinds of commercial applications from flip-flops and running shoe soles to mattresses and yoga mats.

By analogy to the use of animals by native American tribes, the researchers wanted to “use the whole buffalo” in their solution for algae processing waste and therefore figured out how to convert heptanoic acid – another substance in the algae waste stream – into a food flavoring and fragrance.  The flavoring molecule is valued at over $500 per kilogram.

The work, published in the journal Green Chemistry, demonstrates that an algae-source waste stream has both the practical and economic potential to support production of polyurethanes.  The team is already working with shoe companies to commercialize the technology.  With mounting concern over petroleum-based plastic waste, renewable plastic made from algae is an attractive alternative.

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Researchers Turn Algae Leftovers into Renewable Products with Flare

Photo, posted November 8, 2006, courtesy of Adam Moore via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Fresh Produce | Earth Wise

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Fresh fruits and vegetables can sometimes become contaminated by microorganisms during their long journey from fields to restaurants and grocery stores.  Contaminated produce can spoil other produce, which increases the number of fruits and vegetables in the supply chain that can cause illnesses. 

In order to prevent this cross-contamination between produce, researchers from Texas A&M University have designed a coating that can be applied to food-contact surfaces, like buckets, rollers, and conveyor belts.  The newly-created dual-function coating is both water-repellent and germicidal.  In other words, it can both repel and kill.  Without water, the researchers say bacteria can’t stick or multiply on surfaces, drastically reducing contamination.

To make this dual-function coating, the researchers chemically-attached a thin layer of silica to an aluminum sheet.  They then added a mixture of silica and lysozyme, a naturally-occurring germicidal protein found in egg whites and tears.  Together, the silica-aluminum and the silica-lysozyme formed microscopic bumps and crevices.  According to the research team, this rough texture, albeit microscopic, is the key to the coating’s superhydrophobic properties.  

The researchers tested the coating’s effectiveness at curbing the growth of two strains of disease-causing bacteria:  Salmonella and Listeria.  Upon review, the number of bacteria found on the dual-coating surfaces was 99.99% less than what was found on the uncoated surfaces. 

Despite the success in preventing bacterial spread, the research team said more research needs to be done to see how well the coating works for mitigating viral cross-contamination.  Since the coating would need to be reapplied after a certain amount of use, the researchers also plan to develop more permanent, dual-function coatings. 

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New dual-action coating keeps bacteria from cross-contaminating fresh produce

Photo, posted April 14, 2012, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Small-Scale Climate Solutions | Earth Wise

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In order to meet international climate targets, we need to cut greenhouse gas emissions in half over the next decade and reach net-zero by mid-century.  Achieving this will require unprecedented and rapid changes in how energy is supplied, distributed and used.

Researchers at several European universities collected data on a wide variety of energy technologies at different scales and tested how well they performed in accomplishing an accelerated low-carbon transformation. 

Large-scale, costly, non-divisible or so-called lumpy technologies, such as utility-scale generation, nuclear power, carbon capture and storage, high-speed transportation, and whole-building retrofits are often seen as the most effective way to achieve emission-reduction goals. A key finding of their study is that low-carbon technologies that are smaller scale and can be mass deployed are more likely to enable a faster transition to net-zero emissions.

So-called granular options include solar panels, electricity storage batteries, heat pumps, smart thermostats, electric bikes, and ride-share services.  These options scale not by becoming larger but by replicating.

Small-scale options are quicker to deploy, their technologies have shorter lifespans and are less complex, so innovations and improvements can be brought to market more rapidly.  They are also more widely accessible and help create more jobs, giving governments a sound basis for strengthening climate policies.

However, smaller-scale technologies are not a panacea.  There are no small-scale replacements for industrial plants and other kinds of major infrastructure, but in many different contexts, they can outperform larger-scale alternatives as a means of accelerating the low-carbon transformation.

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Smaller scale solutions needed for rapid progress towards emissions targets

Photo, posted April 8, 2019, courtesy of the City of St Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plants Paying For Biofuels | Earth Wise

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Biofuels are an important element in broader strategies to replace petroleum in transportation fuels like gasoline, diesel, and jet fuel.  The idea is that biofuels recycle carbon by getting it from growing plants rather than from fossil sources.  The biggest problem with biofuels is that they cost more than conventional petroleum fuels, so there is economic incentive to keep burning the fossil fuels.

One strategy to make biofuels cost competitive is to have the plants provide additional economic benefits beyond being a feedstock for fuel.  This in principle can be done by engineering plants to produce valuable chemical compounds, or bioproducts, as they grow.  Bioproducts include such things as flavoring agents and fragrances as well as biodegradable plastic.  These bioproducts can be extracted from the plants and then the remaining plant material can be converted to fuel. 

Researchers at Lawrence Berkeley National Laboratory recently published a study to determine what quantities of bioproducts plants need to produce to result in cost-effective biofuel production.

The study looked at a compound called limonene, which is used for flavoring and fragrance.  They calculated that if this compound was accumulated at 0.6% of the biomass dry weight, it would offer net economic benefits to biorefineries.  This corresponds to recovering 130 pounds of limonene from 10 tons of sorghum on an acre of land.

Such quantities are completely practical but, on the other hand, none of these substances are needed in huge quantities. Just six refineries could supply the world with limonene.  So, fuel crops would need to be engineered to produce a broad range of bioproducts to enable a viable cost-effective biofuel industry.

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Making Biofuels Cheaper by Putting Plants to Work

Photo, posted September 28, 2019, courtesy of Michele Dorsey Walfred via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conservation In Vermont | Earth Wise

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In recent times, Vermont and neighboring states have been losing forest land to development at a rate of almost 1,500 acres per year.  With forest fragmentation gaining ground across New England, conserving land for future generations of people, wildlife, and plants has become both increasingly important and increasingly difficult.

According to a new study published by researchers at the University of Vermont, the state has already protected a third of the highest priority targeted lands needed to protect and connect valuable wildlife habitats and corridors.  The protected lands amount to 1.3 million acres.

Most of the currently conserved lands are forested.  However, there are high-priority targeted surface water and riparian areas – ponds, rivers, shorelines, and wetlands – and not nearly enough of these have been protected.  (Many animals require zones along waterways in which to travel between the habitats they need to survive).

The state of Vermont and a number of partners have laid out a comprehensive and thoughtful vision that would ensure that Vermont remains a good place for all forms of life in the future.  The new study provides a crucial benchmark of current levels of forest protection to help prioritize future conservation actions. 

Three groups dominate in responsibility for the state’s protected lands:  the federal government, the state government, and private non-profit organizations.  (Each of these account for roughly a third of existing protected lands).

Going forward, Vermont’s nonprofits will play an increasingly important role in land conservation, especially in continuing to protect those areas that are rich with species diversity.  Nonprofits are engaging more and more deeply in restoring wetlands that were previously degraded, planting new forests along river shores, and protecting unique natural communities while also protecting working forests and farmland.

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Vermont Has Conserved One Third of the Land Needed for an Ecologically Functional Future

Photo, posted June 15, 2014, courtesy of Wesley Carr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

American Robins And Climate Change | Earth Wise

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American robins are migratory songbirds that can be found throughout much of North America.  Named after European robins because of their reddish-orange breast, American robins are often found hopping across lawns and nesting on porches.  Their rich caroling is among the first pre-dawn bird songs heard in spring and summer.  

While some overwinter in northern parts of the United States and southern Canada, most American robins migrate south to overwinter in places like Florida and the Gulf Coast, as well as central Mexico and the Pacific Coast.  They typically head south by the end of August and return north sometime between February and March to their breeding grounds in Canada and Alaska.  They spend their short time there trying to find a mate, build a nest, raise a family, and consume enough food to sustain themselves on their long return journey south.

But climate change is making these seasonal rhythms less predictable.  According to a new study recently published in the journal Environmental Research Letters, American robin migration is kicking off earlier by about five days each decade.  The birds now migrate 12 days earlier than they did in 1994.  

For 25 years, researchers at Canada’s Slave Lake have been recording the timing of American robin spring migration.  They attached GPS devices to 55 robins, tracking their movements from April through June. The researchers linked the birds’ movement with weather data, including air temperature, snow depth, wind speed, and precipitation.  The results showed that robins start migrating north earlier when winters are warm and dry. 

Understanding the influence over the timing of migratory events is important because the timing of migration can influence reproductive success.

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A Migration Mystery

American robins now migrate 12 days earlier than in 1994

Photo, posted January 1, 2020, courtesy of Becky Matsubara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Extreme Wildfire Seasons | Earth Wise

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According to a new study led by researchers at Stanford University, autumn in California feels more like summer now as a result of climate change, and this hotter and drier weather increases the risk of longer and more dangerous wildfire seasons.

The research team, whose work was recently published in the journal Environmental Research Letters, found that the frequency of extreme fire weather conditions in the fall in California has doubled since the early 1980s.  Average temperatures during the season have increased by more than 2 degrees Fahrenheit, and rainfall has fallen by approximately 30%.  The most pronounced warming has occurred in the late summer and early fall.  That finding means that tinder-dry conditions coincide with the strong “Diablo” and “Santa Ana” winds that are typical in California at this time of year.     

In recent years, these conditions have fed large and fast-moving wildfires across California.  The state’s two largest wildfires, two most destructive wildfires, and the most deadly wildfire all occurred during 2017 and 2018, resulting in more than 150 deaths and $50 billion in damage.

Because summertime has typically been peak fire season, the recent spate of autumn fires is putting a strain on firefighting resources and funding.  The ongoing COVID-19 pandemic could further strain emergency resources.  Since fire-prone regions have historically shared  wildfire-fighting resources throughout the year, the consequences of California’s extended wildfire season could have a global impact.  (For example, California’s recent autumn wildfires have coincided with the beginning of wildfires in Australia). 

The researchers highlight some opportunities to manage the intensifying wildfire risk in California, including limiting the trajectory of global warming in keeping with the targets identified in the United Nations’ Paris agreement.

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Researchers forecast longer, more extreme wildfire seasons

Photo, posted September 12, 2019, courtesy of the California National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Hidden Source Of Arctic Carbon | Earth Wise

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Researchers from the University of Texas at Austin, the U.S. Fish and Wildlife Service, and Florida State University have published a paper presenting evidence of significant and previously undetected concentrations and fluxes of dissolved organic matter entering Arctic coastal waters.  The source of the organic matter is groundwater flow atop the frozen permafrost.  The groundwater moves from land to sea unseen, but the new research reveals that it carries significant concentrations of carbon and other nutrients to Arctic coastal food webs.

Globally, groundwater is important for delivering carbon and other nutrients to oceans, but in the Arctic, where much water is trapped in the permafrost, its role was thought to be minimal.  But the new research reveals that groundwater may be contributing an amount of dissolved organic matter to the Alaskan Beaufort Sea that is comparable to what comes from neighboring rivers during the summer.

The researchers found that shallow groundwater flows beneath the surface and picks up new, young organic carbon and nitrogen, but it also mixes with layers of deeper soils and thawing permafrost, picking up and transporting century-to-millennia old organic carbon and nitrogen.  This material is unique because it is directly transported to the ocean without seeing or being photodegraded by sunlight and may be valuable as a food source to bacteria and higher organisms that live in Arctic coastal waters.

The study concluded that the supply of leachable organic carbon from groundwater amounts to as much as 70% of the dissolved organic matter that enters the Beaufort Sea from rivers during the summer.  The role that groundwater inputs play in Arctic coastal ecosystems will be an area of active research for years to come.

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Hidden Source of Carbon Found at the Arctic Coast

Photo, posted June 14, 2015, courtesy of Eugen Marculesco via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Natural Habitats And Strawberry Farms | Earth Wise

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According to a new study led by researchers from the University of California – Davis, conserving natural habitat around strawberry fields can protect farmers’ yields, their bottom line, and the environment.  The study also suggests that conserving natural habitat in this way has no detectable threat to food safety. 

In this study, which was recently published in the journal Ecological Applications, the research team conducted surveys and experiments at 20 strawberry farms along California’s Central Coast.  This region is responsible for 43% of the nation’s strawberry production. 

The researchers found that strawberry farmers were better off with natural habitat, like forests, grasslands, wetlands, and shrubs, around their farms than without it.  According to the study’s models, adding natural habitat can reduce crop damage costs by 23%.  Removing natural habitat can increase costs by as much as 76%. 

Importantly, the strawberry farms with natural habitat surrounding them showed no signs of increased fecal contamination.  While bird feces were regularly encountered on the ground, only 2 of 10,000 strawberries examined show signs of direct fecal contamination.  Those contaminated berries would be discarded during the hand-harvesting process.   

These findings run contradictory to current best practice recommendations that support natural habitat removal around strawberry farms in order to decrease bird fecal contamination and crop damage.  These food safety requirements were a consequence of the deadly outbreak of E. coli in 2006, which was traced back to spinach grown in this region.   

It seems like our agricultural landscapes can both support and benefit from biodiversity. 

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Natural habitat around farms a win for strawberry growers, birds and consumers

Photo, posted June 16, 2011, courtesy of the USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Arctic Permafrost | Earth Wise

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Permafrost is frozen ground – a combination of soil, rock, sand, and ice – that remains at or below freezing for at least two consecutive years.  Approximately 25% of the land in the Northern Hemisphere meets this criterion, the majority of which can be found in northern Russia, Canada, Alaska, Iceland, and Scandinavia.

But as a result of the changing climate, these permafrost soils in the Arctic are beginning to thaw.  As they thaw, large quantities of greenhouse gases could be released, further accelerating climate change.  

A new study recently published in the journal Scientific Reports explores an unconventional countermeasure: resettling massive herds of large herbivores.  According to researchers from the University of Hamburg in Germany, herds of horses, bison, and reindeer could be used to significantly slow the loss of permafrost soils. 

During Arctic winters, the air temperature is often much colder than the permafrost.  Thick layers of snow can insulate the ground from the frigid air, keeping the permafrost warm (relatively speaking). But when the snow cover is scattered and compressed by the hooves of grazing animals, the insulating effect is reduced, which intensifies the freezing of the permafrost.

If climate change continues unchecked, the research team expects permafrost temperatures to rise 3.8-degrees Celsius.  This would result in half of the world’s permafrost thawing by the year 2100.  But in contrast, researchers found that the permafrost would only warm by 2.1 degrees Celsius with the resettled animals.  This 44% reduction in permafrost temperature would preserve 80% of the existing permafrost by 2100.

Natural manipulations of ecosystems could have tremendous results. 

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How horses can save the permafrost

Photo, posted July 17, 2012, courtesy of Kitty Terwolbeck via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Birdseed And Weeds | Earth Wise

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More than 55 million adult Americans feed wild birds and along the way spend more than three billion dollars a year on bird food as well as nearly a billion on bird feeders, bird baths, bird houses and other bird feeding accessories.  Feeding birds is a very popular hobby in both the United States and the United Kingdom.

Researchers at the University of Missouri in Columbia Missouri investigated the content of 98 commercially available bird feed mixes.  They uncovered several significant things.

The various mixes contained seeds from 29 weed species and almost all of the mixes contained seeds for pigweed, which can be a significant threat to agriculture.  One in ten of the mixes contained Palmer amaranth or waterhemp seeds that demonstrated a resistance to glyphosphate.   Other common weed species found in many of the mixes were kochia, common ragweed, foxtail species, and wild buckweed.

The overall collection of seed mixes contained an average of 363 amaranthus seeds in each kilogram of bird feed.  Based on this, it is possible that 105 million amaranthus seeds are transported in bird feed mixes each year.

According to the researchers, it is difficult to estimate the exact role that commercial bird seed plays in spreading troublesome weed species into new regions, but it is clear that the widespread use of these seed mixes is a contributing factor to the spread of weeds.

The researchers recommend careful weed management in crop fields designated for bird feed, as well as sieving during packaging to reduce weed seed contamination.  They also noted that regulatory measures adopted in Europe to limit weed seed content in bird seed have proven to be effective.

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Examination of commercially available bird feed for weed seed contaminants

Photo, posted August 18, 2013, courtesy of Emma Craig via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keep Track Of Your LEGOs | Earth Wise

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Plastics in the ocean are a global problem that has attracted a great deal of attention.  Most of the concern surrounds grocery bags, bottles, six-pack rings, and similar items.  Recent research looked at another source of plastic pollution:  LEGOs.

According to environmental scientists at the University of Plymouth in the United Kingdom, it can take more than a thousand years for LEGO bricks to break down in the ocean.  The iconic toys are made from a strong plastic called acrylonitrile butadiene styrene or ABS.  Pieces of LEGOs are commonly found in ocean trash hotspots and wash up on shores across the globe by the thousands.

LEGOs are one of the most popular children’s toys in history and part of what makes them so popular is their durability.  Barefooted parents stepping on one on the floor in a dark room can attest to that fact.  But the full extent of their durability came as a surprise to the researchers.

The scientists analyzed pieces of weathered LEGOs collected from beaches, confirmed their age, and compared them to unweathered LEGOs from the 70’s and 80’s.  They were able to determine the extent to which LEGOs had been worn down by ocean waves, sand, and salt over time.  And it was surprisingly little.

LEGO has acknowledged the environmental impact of its products and has launched a goal to make its bricks from more sustainable sources such as sugarcane-based polyethylene by 2030, as well as improve its efforts to recycle and reuse old LEGO plastic.

Meanwhile, we should all we careful of where our old LEGOs end up.

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LEGO Bricks Could Linger in the Ocean for 1,300 Years, Study Finds

Photo, posted August 24, 2015, courtesy of Juan Luis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lifestyle And Carbon Footprint | Earth Wise

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Many studies have shown, to no great surprise, that affluent lifestyles lead to larger carbon footprints. Households in Switzerland enjoy a high standard of living and a team of researchers there has been studying the consumption and travel habits of Swiss citizens to better understand the impact of various factors on carbon footprint. Key factors include household composition and income, and whether the households are in the city or the countryside – even though, in the end, people’s lifestyles do not differ greatly from one environment to another. 

A team of researchers at EPFL’s School of Architecture, Civil and Environmental Engineering analyzed data from Switzerland’s household budget survey for 2008, 2011 and 2014.  They combined that data with an environmentally extended input-output analysis to assess households’ carbon footprints by measuring their direct and indirect emissions.

Overall, households in the countryside have larger carbon footprints than those in the city, mainly because they travel more and use more energy in their homes. But urban households have larger carbon footprints than their rural counterparts when it comes to food, clothing, cultural activities and air travel.  

A household’s composition directly influences its carbon footprint. A two-person household has the largest per-capita carbon footprint, and it falls as the size of the family grows since many of the same resources are shared by more people. 

Income levels play an important role.  People consume without much thought because they can afford to and enjoy doing it. But there is a trend towards people becoming more conscious of their levels of consumption and trying to be more responsible in Switzerland.  Overall consumption has actually declined over the years studied.  

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Our carbon footprint is highly impacted by how we live

Photo, posted December 19, 2017, courtesy of Alexander Kozik via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Kind Of Antibiotic | Earth Wise

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Antimicrobial resistance is a serious and growing problem for public health.  Over time, more and more types of bacteria have become resistant to known antibiotics making it very difficult to treat various kinds of infections. 

A new group of antibiotics with a unique approach to attacking bacteria has been discovered at McMaster University in Canada, representing a promising new clinical approach in the fight against antimicrobial resistance. 

The newly found corbomycin and the lesser-known complestatin have a never-before-seen way to kill bacteria, namely, breaking the function of the bacterial cell wall. Bacteria have a wall around the outside of their cells that gives them shape and is a source of strength.  Antibiotics like penicillin kill bacteria by preventing building of the wall, but the new antibiotics work by doing the opposite – they prevent the wall from being broken down. Breaking down the cell wall is critical for cells to divide. In order for bacteria to grow and spread, they need to expand and divide. By completely blocking the breakdown of the wall, it is as if the bacterium is trapped in a prison and can’t expand or grow. 

The researchers demonstrated in mice that these new antibiotics can block infections caused by the drug resistant Staphylococcus aureus which is a group of bacteria that can cause many serious infections. 

The researchers believe this new approach can be applied to other antibiotics and lead to the discovery of new ones with different mechanisms of action. This study found one completely new antibiotic, but since then, they have found a few others in the same family that have this same new mechanism. 

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Antibiotics discovered that kill bacteria in a new way

Photo, posted March 15, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Safer Disposal Of Printed Circuit Boards | Earth Wise

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Printed circuit boards are key elements of modern electronic devices that support and connect all of their electronic components.  On average, they are composed of 30% metallic and 70% nonmetallic substances.

Once the circuit boards have served their purpose, they are often burned or buried in landfills, and can pollute the air, soil, and water.  The biggest problem is that they have brominated flame retardants added to them in order to keep them from catching fire.  Compounds in brominated flame retardants have been linked to endocrine disorders and fetal tissue damage.

Many circuit boards are recycled to recover valuable materials – generally the metals they contain.  But recycling has its own problems.  Metallic components can be recovered from crushed circuit boards by magnetic and high-voltage electrostatic separations.  When the metals are removed, what remains are resins, reinforcing materials, brominated flame retardants, and other additives, which are of little value and present various dangers.

Researchers at Sun Yat-sen University in China have developed a ball-milling method to break down these potentially harmful compounds, enabling safe disposal.  A ball mill is a rotating machine that uses small agate balls to grind up materials. The researchers also added iron powder, which helps remove bromine from organic compounds by breaking the carbon-bromine bonds in the flame retardants.  The result was particles with half of their bromine content removed as well as decomposition of phenolic resin compounds.

The ever-increasing proliferation of device technology had led to a new set of pollution and waste challenges facing society.  Research on ways to reduce the impact of high-tech garbage is an important need for society.

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Toward safer disposal of printed circuit boards

Photo, posted February 18, 2018, courtesy of Diego Torres Silvestre via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Blue Acceleration | Earth Wise

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The oil and gas sector is the largest ocean industry.  It’s responsible for about one third of the value of the ocean economy.  Sand and gravel, destined for the construction industry, are the most mined minerals in the ocean.  And during the past 50 years, approximately 16,000 desalination plants have popped up around the world to help supply people with an increasingly scarce commodity: freshwater. 

As a result of these and other human pressures, the world’s oceans have suffered a lot over time.  But according to a comprehensive new analysis on the state of the ocean, human pressure on the world’s oceans, driven by a combination of technological progress and declining land-based resources, sharply accelerated at the start of the 21st century.  Scientists have dubbed this dramatic increase, which shows no signs of slowing down, the “Blue Acceleration.”

A  research team from Stockholm University analyzed 50 years of data from aquaculture, bioprospecting, shipping, drilling, deep-sea mining, and more.  Their findings were recently published in the journal One Earth.

While claiming ocean resources and space is not new, lead author Jean-Baptiste Jouffray from the Stockholm Resilience Centre says “the extent, intensity, and diversity of today’s aspirations are unprecedented.”

The researchers also highlight how not all human impacts on the ocean are negative.  For example, offshore wind farm technology has reached commercial viability allowing the world to reduce reliance on fossil fuels.

But how can the Blue Acceleration be slowed?  Since only a handful of multinational companies dominate sectors like the seafood industry, oil and gas exploitation, and bioprospecting, one idea is to have banks and other investors adopt more stringent sustainability criteria for making ocean investments. 

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Human pressure on world’s ocean shows no sign of slowing

Photo, posted October 29, 2008, courtesy of Silke Baron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Immersion In Nature Is Good for You | Earth Wise

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There is a growing body of research that shows that getting outdoors in nature can be good for people’s health and well-being. There are so many studies supporting this idea that policymakers, employers, and healthcare providers are increasingly considering this need for nature in how they plan and operate.

A new study of 20,000 people by researchers at the University of Exeter in the UK actually looked at how much exposure to nature was enough to make people say they feel healthy and have a sense of well-being.   The answer turned out to be 2 hours a week.  And the correlation was strong.  People who didn’t meet that threshold did not report the benefits.

Studies have shown that time in nature – as long as people feel safe where they are – is an antidote for stress.  It can lower blood pressure and stress hormone levels, reduce nervous system arousal, enhance immune system function, increase self-esteem, reduce anxiety, and improve mood.  Most of these studies are correlational rather than causal, but the results tend to be robust.

Given all this, cities are adding or enhancing parks, and schools and other institutions are being designed with large windows and access to trees and green space.  The Scandinavian tradition of “forest schools” – where learning takes place in natural settings outdoors -.is finding a home in the US.   Japanese researchers study the effects of “forest bathing”, a poetic term for walking in the woods.

With two-thirds of humanity projected to be living in cities by 2050, we are awakening to the idea that we need to be able to spend time in nature for our own wellbeing, even if it’s just a walk in a park.

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Web Links

Ecopsychology: How Immersion in Nature Benefits Your Health

Photo, posted November 6, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Value Of Abandoned Agricultural Lands | Earth Wise

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It is perhaps surprising to learn that more land is now being abandoned by farming than converted to it. In fact, abandonment of rural lands has become one of the most dramatic planet-wide changes of the modern era, affecting millions of square miles of land.

In part, it is due to rural flight driven by the economic, social, and educational appeal of cities.  It is also a result of climate change and the globalization of the food supply chain.  The global footprint of agriculture has been decreasing over the past twenty years but the global food supply isn’t shrinking.  The lost land has generally been marginal and farming elsewhere has become more productive.

Many researchers see abandoned agricultural lands as a huge opportunity for ecological restoration and strengthening of biodiversity.   Others see these lands as an opportunity for a massive program to plant trees to reduce carbon dioxide in the atmosphere.  A recent study published in Science estimated that planting trees on abandoned agricultural lands could remove 25% of the carbon dioxide humans have added to the atmosphere.

There are strong criticisms to all of these ideas.  In most cases, the studies don’t incorporate the social context of why these lands are in transition, the potential effects on local populations, whether the lands are publicly or privately owned, and whether lands now suitable for regeneration will remain so as climate change advances.

Current government initiatives on degraded lands typically lack even rudimentary planning.  There are real opportunities presented by the vast amounts of abandoned agricultural lands, but there are many caveats and many issues to confront.  As a society, we have barely begun to even think about what to do.

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Web Links

Could Abandoned Agricultural Lands Help Save the Planet?

Photo, posted May 9, 2010. courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)