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Cleaning Up Forever Chemicals | Earth Wise

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PFAS, per- and polyfluoroalkyl substances, are chemical pollutants that threaten human health and ecosystem sustainability.  They are used in a wide range of applications including food wrappers and packaging, dental floss, firefighting foam, nonstick cookware, textiles, and electronics.  Over decades, these manufactured chemicals have leached into our soil, air, and water.  Chemical bonds in PFAS molecules are some of the strongest known, so the substances do not degrade easily in the environment.

Studies have shown that at certain levels, PFAS chemicals can be harmful to humans and wildlife and have been associated with a wide variety of health problems.

Currently, the primary way to dispose of PFAS chemicals is to burn them, which is an expensive multistep process.  Even trace levels are toxic, so when they occur in water in low amounts, they need to be concentrated in order to be destroyed.

Researchers at Texas A&M University have developed a novel bioremediation technology for cleaning up PFAS.  It uses a plant-derived material to absorb the PFAS which is then eliminated by microbial fungi that literally eat the forever chemicals.

The sustainable plant material serves as a framework to adsorb the PFAS.  That material containing the adsorbed PFAS serves as food for the fungus.  Once the fungus has eaten it, the PFAS is gone. 

The EPA has established a nationwide program to monitor the occurrence and levels of PFAS in public water systems and is considering adding PFAS threshold levels to drinking water standards.  If this happens, the technology developed at Texas A&M may become an essential part of municipal water systems.

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Texas A&M AgriLife develops new bioremediation material to clean up ‘forever chemicals’

Photo, posted August 10, 2013, courtesy of Mike Mozart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Marine Protected Areas | Earth Wise

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Marine protected areas are regions of seas, oceans, estuaries, and in the US, the Great Lakes, that are afforded special protections.  MPAs restrict human activity for conservation purposes, generally in order to protect natural or possibly cultural resources.   MPAs may limit such things as development, fishing practices, fishing seasons, catch limits, moorings, and removal or disruption of marine life.

A new study by the University of Plymouth in the UK looked at the effectiveness of MPAs in increasing the total abundance of reef species.  It looked at the MPAs in Lyme Bay, off the south coast of England, where two of them are co-located but governed by different constraints.

The study found that whole-site management of an MPA can increase the total abundance of reef species within its borders by up to 95%.  This is in contrast to the MPA where only known features are conserved and human activity is otherwise allowed to continue unchecked.  In that place, species abundance increased by only 15%.

The whole-site MPAs were observed to have other benefits as well.   They show higher levels of functional redundancy, meaning that when there are species losses, they are compensated by other species.  Whole-site MPAs also exhibit higher levels of species diversity.

MPAs are increasingly being recognized as a sustainable way to enhance the marine environment even while supporting coastal communities.  The Global Ocean Alliance, a 72-country alliance led by the UK, has set a target of protecting 30% of all marine areas by 2030.  The new study shows that even more important than simply establishing marine protected areas, it is essential that they are effectively implemented.

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Whole-site management of Marine Protected Areas can lead to a 95% increase in reef species

Photo, posted October 28, 2011, courtesy of Benjamin Evans via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Cotton More Sustainable | Earth Wise

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In the United States, cotton is a $7 billion annual crop grown in 17 states.  Cotton plants in the largest producing countries in the world – India, China, and the U.S. – are genetically very similar and, like other crops that lack diversity, can be at risk.

Cultivated cotton around the world has been bred to look and act very similar.  It is high yielding and easy to harvest using machines.  But it is also wildly unprepared to fight disease, drought, or insect-borne pathogens.

Researchers are looking beyond breeding for ways to combat the low genetic diversity of cultivated cotton.  There are new approaches that combine breeding with elements of genetic modification.  Most cotton in the U.S. has already been genetically modified to resist caterpillar pests.  But as new problems emerge, new solutions will be needed that may require complicated changes to the cotton genome.  Getting regulatory approval for a genetically modified crop is a long and expensive process.

However, ordinary genetic modification is not the only possibility.  Modern genetic sequencing technology can allow researchers to examine various wild cotton varieties and identify the genetic markers for desirable traits.  Once valuable genes in wild species have been identified, traditional plant breeding techniques could be used to produce cultivated cotton varieties that are more resistant to disease and drought.

Climate change is raising average global temperatures and some important cotton-producing regions such as the U.S. Southwest are becoming drier.  Researchers are hoping to produce cultivated cotton that can tolerate drought at the seedling stage.  The ultimate goal is to create more sustainable and genetically diverse cotton that can thrive in a changing world.

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Cotton Breeders Are Using Genetic Insights To Make This Global Crop More Sustainable

Photo, posted November 9, 2008, courtesy of BP Takoma via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Progress On Perovskite Solar Cells | Earth Wise

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Perovskites are semiconductors with a specific crystal structure.  Their properties make them well suited for making solar cells.  They can be manufactured at room temperature, using much less energy than it takes to make the silicon-based solar cells widely used today.  As a result, perovskite solar panels would be cheaper and more sustainable to produce.  Manufacturing silicon solar cells takes a lot of energy because silicon is forged at around 3000 degrees Fahrenheit. In addition, perovskites can be made flexible and transparent, making it possible to use them in ways unavailable with silicon solar technology.

But unlike silicon, perovskites are very fragile.  The early solar cells made from perovskites in 2009 and 2012 lasted for only minutes.  Lots of potential, but little practicality.

Recently, Princeton Engineering researchers have developed the first perovskite solar cell with a commercially viable lifetime, which is a major breakthrough.  The team projects that the device can perform above industry standards for about 30 years, which is much more than the 20 years designated as a viability threshold for commercial cells.

The research team has developed an ultra-thin capping layer between two of the layers of a perovskite solar cell.  The layer is just few atoms thick but has been demonstrated to dramatically increase the durability of the device. 

There is great potential for the new solar cell technology.  It has efficiency to compete with silicon cells but can be tuned for specific applications and can be manufactured locally with low energy inputs.  If successfully commercialized, the result will be solar panels that are cheaper, more efficient, and more flexible than what are available today.

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Once seen as fleeting, a new solar tech shines on and on

Photo, posted January 8, 2020, courtesy of David Baillot/UC San Diego Jacobs School of Engineering via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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Declining Bird Populations | Earth Wise

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A study by scientists from multiple institutions around the world including Cornell University has found that significant declines in bird populations are taking place across the planet.  Loss and degradation of natural habitats, direct overexploitation of many species, and climate change are driving the bird population declines.

According to the study, approximately 48% of existing bird species worldwide are known or suspected to be undergoing population declines.  The populations of 39% of bird species appear to be stable.  Only 6% of birds have increasing populations.

A study in 2019 determined that nearly 3 billion breeding birds have been lost in the U.S. and Canada over the past 50 years.  The new study shows that the same patterns of population decline and extinction are happening globally.  According to the study, there are now the first signs of a new wave of extinctions of continentally distributed bird species.

The ultimate fate of bird populations is strongly dependent on stopping the loss and degradation of habitats.   Habitat loss is generally driven by human demand for resources.  Reducing the human footprint on the natural world is what is needed.  Birds are a highly visible indicator of environmental health, and their declining populations signal a much wide loss of biodiversity and threats to human health and wellbeing.

There is a global network of bird conservation organizations trying to prevent further loss of bird species and bird abundance.  Keeping track of the situation is essential and there is growing participation by the public in bird monitoring.  But ultimately, it depends on governments and society in general to support sustainable resource use and learn how to share the planet with nature.

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Global Bird Populations Steadily Declining

Photo, posted January 9, 2022, courtesy of Martien Brand via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic Recycling Isn’t Working | Earth Wise

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A recent report from several environmental organizations shows that plastic recycling rates in the U.S. have actually declined in the last several years from about 8.7% of discarded plastic to less than 6%.   Meanwhile, since 1980, per capita plastic waste generation has increased 263%, totaling 218 pounds of plastic waste per person as of 2018.

Diminishing recycling rates don’t necessarily indicate a lack of interest by the public.  Plastic recycling is a complicated process.  There are multiple types of plastic that can’t be intermingled and there are no simple and sustainable ways to recycle many forms of plastic.   On top of that, the declining recycling rate also reflects the fact that we no longer can export our plastic waste to countries like China and Turkey, which have banned U.S. waste imports.

Recycling in general is a successful practice.  Paper recycling rates are around 66% as of 2020.  Cardboard recycling was at 88.8% in 2020, and metal recycling rates range from 27% to 76%, depending on the type of metal.  Glass recycling rates are a little over 30%.  Only plastic recycling has never reached 10%, even before shipping our waste overseas and declaring it to be recycled was going on.

According to environmental organizations focused on the global plastic problem, there is no circular economy of plastics.  Perhaps if truly biodegradable plastics became practical, economical, and widely utilized, the situation would be different.  As things stand, the only solution is to reduce the production, use, and disposal of plastics.

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Plastics Recycling ‘Does Not Work,’ Environmentalists Stress as U.S. Recycling Rates Drop to 5%

Photo, posted May 13, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Renewable Use In California | Earth Wise

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California, the most populous state, is the second largest electricity user.  Only Texas, the second most populous state, uses more energy, in part because it consumes large amounts in refining fossil fuels. Overall, California uses about 8% of the electricity generated in the U.S.

Thus, it was a significant milestone when briefly, on April 3, a record 97.6% of the energy on California’s statewide grid came from renewable energy resources.  (The previous record of 96.4% was set just a few days earlier).

Renewable energy’s share of the power typically peaks in the spring when mild temperatures keep demand relatively low and higher sun angles drive greater solar energy production.

On April 8, a record peak solar power production was set at 13,628 megawatts just after noon.  On March 4, the state set an all-time wind generation record of 6,265 megawatts. 

California now has over 15,000 MW of grid-connected solar power and 8,000 MW of wind.  Another 600 MW of solar and 200 MW of wind are coming online by June.  The state also has about 2,700 MW of energy storage online and that will climb to 4,000 MW by June.

In 2020, 34.5% of the state’s retail electricity sales came from wind and solar sources.  Adding in hydropower and nuclear power, nearly 60% of the state’s electricity came from non-fossil fuel.  Despite the effects of drought on hydropower generation and the impact of the pandemic on the pace of renewable energy projects, California continues its dramatic transition to sustainable energy.

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Solar and wind notched records as renewables met California’s energy demand

Photo, posted September 20, 2016, courtesy of Tom Brewster Photography / BLM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coral Reefs And Ecosystem Services

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A new study led by the University of British Columbia provides the first comprehensive look at what climate change, overfishing, and habitat destruction of coral reefs mean for their ecosystem services.  For humans, this means how the global decline in coral reefs has affected their ability to provide essential benefits including food, livelihoods, and protection from storms.

The study found that global coverage of living corals has declined by about half since the 1950s and the diversity of reef species has declined by more than 60%.  So, it is no surprise that there has been a significant loss in the ability of reefs to provide ecosystem services.

The study analyzed data from coral reef surveys around the world, fisheries catches, indigenous consumption, and more.  Apart from the declines in reef coverage and biodiversity, the study found that fish catches on coral reefs peaked in 2002 and has steadily declined since then, despite increased fishing efforts.

The findings of the study led the researchers to conclude that continued degradation of coral reefs in the years to come threaten the well-being and sustainable development of millions of people in communities on the coast that depend on coral reefs.  Fish and fisheries provide essential nutrients in places with few alternative sources of nutrition.  Coral reef biodiversity and fisheries have added importance for indigenous communities, where important cultural relationships exist with reefs.

The study’s authors say that the results are a call to action.  The level of destruction happening all over the world’s coral reefs is threatening people’s culture, their daily food, and their history.  It is not just an environmental issue; it is a human rights issue.

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Photo, posted September 22, 2010, courtesy of David Burdick / NOAA Photo Library via Flickr.

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The Benefits Of No-Till Farming | Earth Wise

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No-till farming is not new.  In fact, it was used as far back as 10,000 years ago.  But during the 18th and 19th centuries, tilling became popular because it allowed farmers to plant seeds more efficiently.

Tilling (or ploughing) is the process of preparing the soil for the cultivation of seeds by overturning the soil.  The practice works animal manure, weeds, and other surface residues deep into the soil.  While this all sounds like a good thing, it’s not. 

Tilling removes plant matter and loosens the soil, leaving the soil bare and vulnerable to erosion.  Tilling also displaces the millions of microbes and insects that form healthy soil biology.  The long-term use of tilling can turn healthy soils into lifeless growing mediums dependent on chemical inputs.  

But no-till farming also tends to rely on chemical inputs like glyphosate for weed control.  According to a new study recently published in Agronomy Journal, researchers at Penn State have found that farmers using no-till farming can reduce herbicide use and still maintain crop yields by implementing integrated weed-management methods.   

The research team conducted a nine-year experiment using herbicide-reduction practices in a crop rotation, which included soybean, corn, alfalfa, and canola.  Some of the practices used to reduce herbicide inputs included seeding small-grain companion crops with perennials, and plowing once in six years to terminate the perennial forage rather than killing it with an herbicide. 

While there was more weed biomass in the reduced herbicide treatment, the researchers found that the added weed pressure did not substantially affect crop yields. 

It is possible to make agriculture more environmentally-friendly and sustainable without sacrificing productivity.

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No-till production farmers can cut herbicide use, control weeds, protect profits

Photo, posted February 11, 2019, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Agriculture’s Carbon Footprint | Earth Wise

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Agriculture is responsible for about 10% of greenhouse gas emissions.  Those emissions come from livestock such as cows, the disturbance of agricultural soils, and activities like rice production.

Recent research from Texas A&M University presents sustainable solutions for grazing agriculture.  According to the research, published in the Journal of Soil and Water Conservation, ruminant animals like cattle contribute to the maintenance of healthy soils and grasslands, and proper grazing management can reduce the industry’s carbon emissions and overall footprint.

Grassland ecosystems co-evolved with herbivores over thousands of years.  These complex, dynamic ecosystems include grasses, soil biota, grazing animals, and predators.  The ecosystems degrade in the absence of periodic grazing.

The research contends that ruminant livestock are an important tool for achieving sustainable agriculture with appropriate grazing management.  With such management, grazing cattle on permanent perennial grasslands helps develop soil biology to improve soil carbon, rainfall infiltration, and soil fertility.

Permanent cover of forage plants is highly effective in reducing soil erosion and increasing soil infiltration.  Ruminants consuming grazed forages under appropriate management results in considerably more carbon sequestration than carbon emissions.

This overall approach is known as regenerative agriculture and is built around the ideas of practices that restore soil health and ecosystem function to support healthy agroecosystems. 

These ideas constitute alternatives to ones that call for the reduction or elimination of cattle and livestock agricultural production.  The future of agriculture needs to consider the full impacts of the entire food production chain and its environmental impacts.

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Grazing Cattle Can Reduce Agriculture’s Carbon Footprint

Photo, posted April 27, 2010, courtesy of Beverly Moseley/USDA NRCS Texas via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wastewater As A Freshwater Source | Earth Wise

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Water covers three-quarters of our planet, but freshwater – the water we drink, bathe in, and irrigate crops with – comprises only 3% of the world’s water and much of that is frozen in glaciers or otherwise unavailable.  Nearly 3 billion people suffer from water scarcity for at least some of the year.

Natural freshwater sources – lakes, rivers, and groundwater – are under stress from the effects of climate change and from the increasing demands of city populations.  The wastewater treatment plants in large cities represent a significant potential water source provided that sustainable and economical technologies to produce it can be developed.

Researchers at Lehigh University in Pennsylvania have patented an innovative ion exchange desalination process that is a legitimate candidate to transform wastewater into usable water.

Existing large-scale desalination systems make use of semipermeable reverse osmosis membranes that require an energy source to run the system.  The Lehigh process, which they call HIX-Desal, harnesses the unique chemistry of carbon dioxide to take the place of the energy used in reverse osmosis systems. 

Tests of the new system show that the salinity of treated wastewater can be reduced by more than 60% by the HIX-Desal process without requiring any reverse osmosis.  At an Allentown, Pennsylvania water treatment plant where the system was tested, the researchers estimated that using the system could save about a million kWh per day in electricity usage, enough energy to power 94 homes for a year.

With this system, waste carbon dioxide from landfills or turbine exhaust can be used to desalinate municipal wastewater.  It could be the basis of a circular economy.

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Desalination tech uses CO2 to tap into municipal wastewater as alternative freshwater source

Photo, posted November 28, 2020, courtesy of Richard Ricciardi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

New York And Green Hydrogen | Earth Wise

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In July, outgoing New York Governor Andrew Cuomo announced plans for the state to explore the potential role of green hydrogen as part of New York’s decarbonization strategy.

Green hydrogen is hydrogen produced using renewable energy, such as wind, solar, and hydro power.  While hydrogen itself is a carbon-free fuel, most of the hydrogen produced today is made with a process called natural gas reforming which has byproducts of carbon monoxide and carbon dioxide.  As a result, the environmental benefits of using hydrogen are largely lost.  Hydrogen is the most plentiful element in the universe but extracting it for use as a fuel is not easy.

Green hydrogen is obtained by splitting water molecules into their constituent hydrogen and oxygen parts.  In principle, oxygen is the only byproduct of the process.  The main drawback of electrolysis, as this process is called, is that it is energy intensive as well as being expensive.  But if that energy comes from renewable sources, then it is a clean process.

New York’s announcement is that the state will collaborate with the National Renewable Energy Laboratory and join two hydrogen-focused organizations to inform state decision-making, as well as make $12.5 million in funding available for long duration energy storage techniques and demonstration projects that may include green hydrogen.

Green hydrogen has the potential to decarbonize many of the more challenging sectors of the economy.  Hydrogen is a storable, transportable fuel that can replace fossil fuels in many applications.  Many experts believe that the so-called hydrogen economy could be the future of the world’s energy systems.  For that to happen, green hydrogen will need to be plentiful, sustainable, and inexpensive.

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New York announces initiatives to explore green hydrogen for decarbonization

Photo, posted October 26, 2019, courtesy of Pierre Blache via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Pesticide From Beer | Earth Wise

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Researchers from the Neiker Basque Institute for Agricultural Research and Development in Spain have demonstrated that a combination of rapeseed cake and beer bagasse can be used to reduce populations of soil parasites and increase crop yields. 

Beer bagasse is spent brewers’ grain – the stuff that is left over after the beer is made.  Beer brewing generates substantial amounts of by-products, including large amounts of spent grain.  It already has some practical uses, including as a feedstock for biofuel, as a food additive, and it even has some medical uses.  But the new research has shown that the bagasse can be the basis for a biodisinfestation treatment to be used in agriculture.  The aim is to disinfect soils, protect soil microorganisms, and increase crop yields.

The actual material studied was a mixture of beer bagasse, rapeseed cake, and a generous amount of fresh cow manure.  The high nitrogen content of the mixture promotes the activity of beneficial microorganisms in the soil, which helps to break down organic matter and kill off nematodes and other parasites that damage crops.

Nematodes are common parasites that can penetrate plant roots to lay their eggs, which damages the root and prevents the plants from absorbing nutrients effectively.  Application of the bagasse-based mixture over 12 months increased crop yields by 15% and boosted healthy soil microbes.

The study demonstrated that agricultural byproducts can be an effective treatment for root-knot nematodes and other soil parasites, increase crop yields, and help promote sustainable food systems to reduce waste from the agricultural industry.  The researchers hope to identify other potential organic treatments for tackling soil parasite problems.

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Beer byproduct mixed with manure proves an excellent organic pesticide

Photo, posted July 1, 2011, courtesy of Quinn Dombrowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Infinitely Recyclable Plastic | Earth Wise

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The glut of plastics is one of the world’s most challenging environmental problems.  The average American generates over 200 pounds of plastic waste each year and most of that ends up in landfills.  Researchers around the globe continue to work on potential solutions to the plastic waste problem.

Two years ago, scientists at Lawrence Berkeley National Laboratory announced the invention of a new plastic that could be an answer to the plastic waste problem.  The material is called polydiketoenamine or PDK and it differs from traditional plastics in a very important way:  it can be recycled indefinitely with no loss in quality because it can easily be broken down into its constituent component monomers and be used to make brand new plastic.

Only a small percentage of plastics are currently recycled.  When many plastics are melted down together, the polymers are mixed with a slew of incompatible additives, resulting in a new material with much lower quality than newly produced plastic.  As a result, less than 10% of plastic is recycled more than once.

Recently, the Berkeley Lab researchers released a study that shows what could be accomplished if manufacturers began using PDKs on a large scale.  They determined that PDK-based plastic could quickly become commercially competitive with conventional plastics and, furthermore, would get less expensive and more sustainable as time goes on.

PDK is starting to draw interest from companies needing to source plastic.  The best initial application for PDKs are markets where manufacturers have the most access to products at the end of their lifespans such as in the automobile industry and consumer electronics.  Making plastics part of a circular economy is a challenging task.

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The Future Looks Bright for Infinitely Recyclable Plastic

Photo, posted April 19, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Wood Into Plastic | Earth Wise

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Plastic pollution is particularly pernicious because plastics can take hundreds of years to degrade in the environment.  For this reason, researchers across the globe search for ways to shift from petrochemical plastics to ones that are biodegradable.

Producing biodegradable plastics is challenging both from the standpoint of the methods needed and from the results obtained.  Producing them often requires toxic chemicals and can be very expensive.  The materials that emerge often do not have the durability and strength of conventional plastics and can be unstable when exposed to moisture.

Researchers at the Yale School of the Environment have developed a process of decomposing the porous matrix of natural wood into a slurry that can be formed into a biodegradable plastic.  The material shows high mechanical strength, stability when holding liquids, and is resistant to the effects of ultraviolet light.  Along with all these favorable properties, the material can be recycled or safely biodegraded in the natural environment.

The slurry mixture is created by taking wood powder – a processing residue usually discarded in lumber mills – and deconstructing it with a biodegradable and recyclable solvent.  The resulting mixture has a high solid content and high viscosity and can be casted and rolled without breaking.

The researchers conducted a comprehensive life cycle assessment to test the environmental impacts of the bioplastic compared with conventional plastics.  Sheets of it were buried in soil and observed to fracture after two weeks and completely degrade after three months.  The material can also be broken back down into the slurry by mechanical stirring.

The remaining topic to investigate is the potential impact on forests if the manufacturing of this bioplastic is scaled up.

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Turning wood into plastic

Photo, posted October 12, 2016, courtesy of the US Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Prickly Pear As A Sustainable Crop | Earth Wise

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The fruits and pads of opuntia, better known as prickly pear cactus, find their way into people’s diets in many arid and semi-arid places around the world.  In Mexico, the pads are known as nopales and are used in a variety of dishes.  The pears themselves are used in jams, salads, and juices.

A five-year study by the University of Nevada Reno College of Agriculture, Biotechnology & Natural Resources investigated the prospects for cactus pear to become a major crop like soybeans and corn and to help provide a biofuel source.

As the climate changes, dry areas are going to get dryer and drought issues will increasingly affect traditional crops.

The study looked at the particular opuntia species called the spineless cactus pear and found that it had the highest fruit production while using up to 80% less water than some traditional crops.  Cactus pear can be used for both human consumption and livestock feed.  As a perennial crop, once the fruit and pads are harvested for food, the remaining biomass can be used for biofuel production.

Corn and sugar cane are the most utilized bioenergy crops right now, but these use three to six times more water than cactus pear.  The cactus pear productivity is on par with corn and sugar cane, but not only do they use a fraction of the water, they also have higher heat tolerance.

Over 40% of land area around the world is classified as semi-arid or arid.  There is enormous potential for planting cactus for carbon sequestration.  If nothing else, it makes great sense to grow cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops.

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Study shows cactus pear as drought-tolerant crop for sustainable fuel and food

Photo, posted April 16, 2020, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Sustainable Polymer From Wood | Earth Wise

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Scientists from the University of Bath in the UK have developed a sustainable polymer using xylose, a sugar found in wood.

The new polymer is a member of the polyether family.  It could be used in a variety of applications, including being a building block for polyurethane, used for example in mattresses and shoe soles. It could also be a bio-derived alternative to polyethylene glycol, a chemical widely used in biomedicine, or in polyethylene oxide, which is sometimes used as an electrolyte in batteries.

Xylose, also known as wood sugar, is one of the most abundant carbohydrates on earth, second only to glucose. Apart from comprising 5-20% of hardwoods, xylose is a major component of straw, corncobs, and many other plant materials.

The new polymer could reduce reliance on crude oil products and its properties can be easily controlled to make the material flexible or crystalline.  Added functionality could be added to it by binding other chemical groups such as fluorescent probes or dyes to the sugar molecule for biological or chemical sensing applications.

Tweaking the physical and chemical properties of bio-derived polymers has previously been a very difficult thing to do.  The Bath researchers discovered that combining two mirror-image chemical forms of xylose results in a stronger and more adaptable material.  They have filed a patent for their technology and are seeking industrial collaborators for further development.

The reliance of plastics and polymers on fossil fuels is a major problem.  Bio-derived polymers, such as this new one, are an important part of the effort to make plastics sustainable.

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Scientists make sustainable polymer from sugars in wood

Photo, posted January 25, 2017, courtesy of Keith Double via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Queen Conch | Earth Wise

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Queen conchs are large sea snails belonging to the same taxonomic group as clams, oysters, and squid.  They live on coral reefs or seagrass meadows in warm, shallow waters.  Queen conchs are found throughout the Caribbean Sea and Gulf of Mexico, ranging as far north as Bermuda and as far south as Brazil.

Reaching up to 12” long and living up to 40 years, the queen conch is prized as a delicacy and revered for its shell.  It’s the second most important sea-bottom fishery in the Caribbean region, trailing only the spiny lobster. 

But queen conchs face a challenge.  Their populations are in a steady rate of decline as a result of overfishing, habitat degradation, and hurricane damage.  In some places, the numbers are so low that remaining conchs cannot find breeding partners.  The situation is urgent from both an ecological and economical perspective. 

As a result, Megan Davis, a scientist from Florida Atlantic University who spent more than four decades researching queen conch, has released an 80-page, step-by-step user manual about how to care for the species. Her work was recently published in the National Shellfisheries Association’s Journal of Shellfish Research.

According to Davis, aquaculture, along with conservation of breeding populations and fishery management, are ways to help ensure longevity of the queen conch.  With requests for mariculture guidance pouring in from communities throughout the Caribbean, Davis and her collaborators are expanding their queen conch conservation, education, and restorative mariculture program.

Their desired outcomes include creating protected breeding areas, establishing sustainable hatcheries, and repopulating protected habitats.

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‘Hail to the queen’: Saving the Caribbean queen conch

Photo, posted June 3, 2012, courtesy of Christopher Gonzalez via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Costs Of Mislabeled Seafood | Earth Wise

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Seafood is the world’s most highly traded food commodity and reports of seafood mislabeling have become increasingly common over time.  A new study by Arizona State University looked at the environmental effects of mislabeled seafood.

What is mislabeled seafood?  Sometimes the snapper you were served was really Pacific Ocean Perch.  Maybe grouper was really whitefin weakfish.  Many times white leg shrimp are actually giant tiger prawns.

Approximately 190,000 to 250,000 tons of mislabeled seafood are sold in the U.S. each year, or 3.4 to 4.3% of consumed seafood.  Previous studies focused on the economic aspects of getting cheaper fish when paying for more expensive fish.  The new research looks at the environmental costs associated with mislabeled seafood.

Substituted seafood is 28% more likely to be imported from other countries, which may have weaker environmental laws than the U.S.  In the United States, fishery management is pretty good.  There is strong monitoring and enforcement to support limits on fishing.  Metrics like fish abundance, fishing mortality, bycatch, and discards are all monitored.  In many other places, this is not the case.

To really evaluate the overall effects of seafood mislabeling, one has to take into account both the rates of substitution and the levels of consumption. 

Consuming fish from a well-managed fishery should not have a negative impact in terms of the population now or in the future.  But even inadvertently consuming fish from poorly managed fisheries in not sustainable.  It is good to get your seafood from a trusted source.

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ASU Study Looks At The Environmental Effects Of Purchasing, Consuming Mislabeled Fish

Photo, posted August 1, 2014, courtesy of Ralph Daily via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydrogen-Powered Jetliners | Earth Wise

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Airbus, the giant European aerospace company, hopes to have hydrogen-powered commercial airliners in the sky by 2035.  Such planes would have no carbon dioxide emissions.

Greenhouse gas emissions from commercial aviation have been a rapidly increasing contribution to the global total.  Of course, the Covid-19 pandemic has drastically reduced air travel, so emissions are currently lower than they have been in a very long time.  But at some point, they will resume at previous levels and continue to increase.

Planes themselves produce over 2% of global CO2 emissions, and between the climate effects of contrails and the emissions associated with the rest of the air travel industry, commercial aviation drives about 5% of global warming.

Airbus is studying design concepts in which planes run off of hydrogen and oxygen fuel and have no carbon exhaust.   Making such planes practical and environmentally advantageous requires solving an array of complex technical challenges. 

One of the biggest challenges is that the hydrogen on the market today is considered to be “brown” rather than green, meaning that it is not a sustainably produced energy source.  Almost all hydrogen produced today comes from natural gas reforming, which results in carbon emissions.  A viable hydrogen-powered aviation technology assumes that producing hydrogen by splitting water molecules into oxygen and hydrogen using renewable energy becomes the standard source for it.

There have been test flights of small planes and drones powered by hydrogen, but Airbus expects that intensive research and development for the next five years will be required to evolve its current preliminary designs to a stage where they could be developed for future use in its product line.  It won’t happen overnight, but according to Airbus, hydrogen planes are coming.

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Web Links

Airbus Hopes to Be Flying Hydrogen-Powered Jetliners With Zero Carbon Emissions by 2035

Photo, posted April 15, 2019, courtesy of Olivier Cabaret via 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...)