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Detecting dangerous chemicals with plants

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Researchers at University of California Riverside have been studying how to enable plants to sense and react to a chemical in the environment without damaging their ability to function in all other respects.  Why do this?  The idea is to be able to use plants as environmental sensors that can detect the presence of harmful substances.

The impetus for the work is presence of a protein in plants that senses a plant hormone called abscisic acid (or ABA) that helps plants acclimate to environmental changes.  During drought, plants produce ABA causing the plant to produce ABA receptor proteins that close pores in its leaves and stems, keeping in moisture.

The UCR researchers demonstrated that these ABA receptor proteins can be trained to bind to chemicals other than ABA.  This ability enabled them to create sensors for many chemicals, including banned pesticides.

In their recent publication, they demonstrated a green plant that turns bright red in the presence of azinphos-ethyl, a banned pesticide.  The goal is to easily detect chemicals in the environment from a distance.  A field of these plants would provide an obvious visual indicator of the use of a banned pesticide.  The researchers also demonstrated the ability to turn a variety of yeast into a sensor that could respond to two different chemicals at the same time.

Ultimately, it would be extremely valuable to design plants that sense dozens of chemicals to they could be used as living sensors that persist for years and provide environmental information.  The sensor plants are not being grown commercially at this time.  That will require regulatory approvals that are likely to take years.  But the discovery opens up real possibilities.

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Plants transformed into detectors of dangerous chemicals

Photo, posted August 29, 2013, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A fern-based insecticide

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A spore-producing bacterium is the source of various crystal toxins (known as Cry proteins) that are widely used in modern agriculture to combat insect pests – generally caterpillars and other larvae – that attack important crops.  Pest control in corn, soybean, and cotton use these insecticidal proteins for protection against major insect pests.  The pesticides are obtained from Bacillus thringiensis (Bt) bacteria to produce the proteins.

Bt Cry proteins are secreted by the bacteria but are harmless to the bacteria.  They are harmless until ingested by insects and are then activated by the alkaline environment in the gut of insects which is entirely different from the acidic environment of our own digestive systems.  In the insect’s gut, the proteins become a powerful feeding inhibitor by breaking down the insect’s gut lining.  Bt Cry proteins are considered safe for humans.

Researchers continue to seek alternative solutions because there are concerns that insect pests could develop resistance to these toxic proteins.

Researchers from two Australian universities have analyzed the structure of a novel insecticidal protein that could be effective in protecting essential crops.  The protein is naturally produced by ferns including common houseplants like brake ferns.

The newly discovered proteins offer a different mode of action from the Cry proteins and therefore are a potential solution to the problem of pest resistance to existing insecticides.  The new family of insecticidal proteins is designated as iPD113 and has been shown to be very effective against caterpillar pests of corn and soybeans.

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Discovery: ferns produce crop-saving insecticide

Photo, posted October 5, 2015, courtesy of Marianne Serra via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Deeper corals bleaching

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When ocean waters get too warm, corals – which are actually tiny animals – eject the colorful algae that inhabit their tissues.  The symbiotic relationship between coral polyps and algae is essential to coral survival   When the algae is ejected, previously colorful coral turns white, and the coral can ultimately die.  If waters cool off, the algae can reestablish themselves and the coral can regain its color and health.

The world’s oceans have been warming at an unprecedented rate, making coral bleaching and die-off a global phenomenon.  It is estimated that half of the planet’s reefs have already disappeared.  Some places are worse off than others.  For example, almost 95% of coral reefs in Southeast Asia are threatened.  Florida’s reefs are especially threatened, particularly since there have been unprecedented marine heatwaves off its coast.

It has long been assumed that deeper reefs, where water is cooler, would remain safe from the effects of warming, but a few years ago researchers recorded coral bleaching some 300 feet underwater along the Egmont Atoll in the western Indian Ocean.  At one point, bleaching affected 80% of corals in some areas.  This discovery came as a huge surprise to oceanographers.  It was probably associated with an El Niño-like phenomenon in the waters and those reefs have mostly recovered in the intervening years.

Fairly recently, researchers have found pristine coral reefs deep down in the waters off the Galapagos Islands, where shallow reefs have largely disappeared.  There are likely to be similar reefs in the ocean depths around the world, but scientists are expressing concern that even coral reefs lying deep beneath the ocean surface may not ultimately be protected from the warming seas.

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As Oceans Warm, Coral Bleaching Seen at Greater Depths

Photo, posted June 5, 2023, courtesy of Ryan Hagerty / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wildlife rebounding in Uganda

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The numbers of elephants, rhinos, and other animals in Uganda’s nature preserves is steadily improving, reversing the trend of steady declines previously caused by poachers, wildlife traffickers, and conflict.

Between the 1960s and 1980s, political conflict and lawlessness in Uganda led to massive declines in some species as poaching, trafficking, and encroachment ran rampant.

Uganda’s population of over 700 northern white and eastern black rhinos was completely wiped out in the early 1980s by people hunting them for their horns.  A charity brought four rhinos in 2005 to a sanctuary called the Ziwa Rhino and Wildlife Ranch and, according to the Uganda Wildlife Authority, there are now 33 in the facility.

Increased conservation efforts have allowed the population of buffalos to increase 77% to over 44,000 since 1983.  The number of elephants has surged almost 300% to nearly 8,000 over that same time period.  There has also been an increase in the number of mountain gorillas in dense forests.

Over the years, the Ugandan government has brought in a string of conservation policies including lengthy jail terms for violations.  As a result, wildlife populations have been on a steady recovery.

It is typical to think about species in terms of how close to extinction they are, but the ultimate goal of conservation is to recover species.  This means not only gaining distance from extinction but also resuming a species’ role in its ecosystem and repopulating its former range.  Whether the wildlife in Uganda is achieving this status remains to be seen, but the trends are very positive.

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Uganda Sees Resurgence of Rhinos, Elephants, Buffaloes

Photo, posted September 15, 2014, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking down PFAS toxins

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PFAS – per- and polyfluoralkyl substances – are a group of organic compounds that have been extensively used to provide water-, oil-, and dirt-resistance to a wide range of products ranging from non-stick pans, clothing, and packaging to paint, car polish, and fire-suppressant foam.  Exposure to specific PFAS compounds is associated with multiple adverse health effects, including altered immune and thyroid function, liver disease, kidney disease, poor reproductive and developmental outcomes, and cancer.  PFAS compounds do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people.

Government agencies such as the EPA in this country and the EU have set strict limits for allowable levels of PFAS in drinking water.  Testing water for the trace amounts of PFAS that constitute the limits is time-consuming and expensive and requires complex equipment and experienced personnel.

Researchers at MIT have now introduced a technique for making a portable, inexpensive test that can easily and selectively detect PFAS in water samples.  The test makes use of a special polymer containing fluorinated dye molecules that cause the polymer to fluoresce red.  If PFAS are present in the sample, they enter the polymer and displace the dye molecules and switches off the red fluorescence. 

The new technique is suitable for on-site detection in highly contaminated regions.  Detecting smaller concentrations can be achieved with sufficient precision after pre-concentrating the samples using the process of solid-phase extraction.

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Tracking down Environmental Toxins

Photo, posted October 16, 2021, courtesy of Nenad Stojkovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electricity from chicken feathers

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The food industry generates enormous amounts of waste and by-products.  Each year, 40 million tons of chicken feathers are incinerated, causing adverse environmental effects.  Not only does it release large amounts of carbon dioxide but also produces toxic gases such as sulfur dioxide.

Researchers at ETH Zurich in Switzerland and Nanyang Technological University in Singapore have developed a way to put chicken feathers to good use by using them to make fuel cells more cost-effective and sustainable.

Using a simple and environmentally friendly process, they extract the keratin from the feathers.  Keratin is the protein that helps form hair, nails, the outer layer of skin, and feathers.  The extracted keratin is then converted into ultra-fine fibers known as amyloid fibrils.  The keratin fibrils are used in the membrane of a fuel cell.

Fuel cells generate clean energy from hydrogen and oxygen with only heat and water as byproducts.  At the heart of every fuel cell is a semipermeable membrane that allows protons to pass through but blocks electrons, thereby producing an electric current.  Fuel cells are the primary way hydrogen is used to directly generate electricity.  Hydrogen cars run on fuel cells.

Conventional fuel cells typically use membranes made from highly toxic chemicals.  The new ETH membranes essentially replace these toxic substances with biological keratin. 

The researchers are investigating how stable and durable their keratin membrane is and to improve it if necessary.  The team has already applied for a joint patent and is looking for partners and investors to further develop the technology and bring it to market.

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Generating clean electricity with chicken feathers

Photo, posted July 10, 2016, courtesy of Matthew Bellemare via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electric planes: Fantasy or reality?

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Airplanes have been around for over a century, but the idea of powering them with electricity rather than with liquid fuels has been little more than a fantasy.  Over the years, billions of dollars have been invested trying to make electric planes practical.  In recent times, progress on battery technology has provided a much-needed boost for the field.

Electric planes are nowhere near becoming competitive with long distance commercial aircraft.  The weight and power requirements for such craft are far beyond what electric plane technology can do.  But electric planes could offer a very practical solution for transporting relatively small numbers of passengers over relatively short distances.

A plane built by the well-funded private company Beta Technologies has flown as far as 386 miles on a single battery charge.  The company envisions such planes to be mostly used for trips of 100 to 150 miles.  These planes could open new opportunities, like better connecting rural areas that have little or no direct air service.

Their latest model was tested on a trip between Burlington, Vermont and Florida, making multiple stops and flying through congested airspace over Boston, New York, and Washington.

Commercial versions of the planes will likely have lift rotors to take off and land like helicopters, making them deployable in a wide range of places.  Many companies are working on electric aviation, and they have backers like major automakers, major airlines, and large investment firms. 

Electric planes are not likely to replace conventional aircraft but are likely to have a meaningful impact how we move goods and services and reconnect rural parts of the country.

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Electric Planes, Once a Fantasy, Start to Take to the Skies

Photo courtesy of Beta Technologies.

Earth Wise is a production of WAMC Northeast Public Radio

Protecting berries with sunflower extract

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Many of us buy blueberries, raspberries, blackberries, and more in those little clear plastic clamshell boxes.  We try to check them out at the store to make sure they are ok and even if are, many soon end up coated with gray mold and other fungi.  It is a problem that is both disappointing and expensive.

Researchers from several Chinese Universities recently reported that compounds extracted from sunflower crop waste are quite effective at preventing rotting in blueberries.  They suggest that the food industry could use these natural compounds to protect berries from postharvest diseases.

Sunflowers are grown globally for their seeds and oil.  The flower stems themselves are generally considered to be a waste product.  Sunflowers are known to be particularly resistant to many plant diseases so the researchers decided to investigate whether there might be chemical constituents within the plants that are responsible for the protective property.

Their research led to the isolation of 17 different compounds known as diterpenoids, including four that have never been identified before.  They found that 4 of the compounds, including 2 of the newly discovered ones, were effective at preventing the growth of fungus on the blueberries. 

Berries were wetted with the compounds and then dried off and injected with mold spores.  Half of the treated berries were protected from the mold.

There is no reason that the method couldn’t be applied to a variety of crops.  There is great appeal in the concept of using a harmless extract from a plant to render a food crop safe from fungal infestation.  The technique holds great promise in preventing postharvest disease in fruit.

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Sunflower extract fights fungi to keep blueberries fresh

Photo, posted August 26, 2006, courtesy of Liz West via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Buildings and birds

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Birds face a wide range of dangers.  Billions of them each year face violent deaths.  Concerned individuals point at such things as wind turbines, which in fact do kill hundreds of thousands of birds.  But the great majority of bird deaths are caused by cats.  And that’s a danger that isn’t going to go away.

The second largest cause of bird deaths is collisions with building windows.   Building collisions kill hundreds of millions of birds each year in the U.S. alone.  As other places have seen glass skyscrapers proliferate, such as in Chinese cites, these collisions have become a major global factor in bird mortality.

There are growing efforts across the U.S. and Canada to reduce bird collisions.  Many businesses are taking part in “lights out” programs in which their buildings dim lights during spring and fall migrations.  Some buildings now use special glass that birds can see and avoid.  Some communities even have adopted ordinances that require bird-friendly glass in new construction.  Keeping bird attractants away from windows is another important way to reduce bird strikes.  All these measures have been proven to be effective in reducing the number of bird collisions.

 Companies sell vinyl film with tiny dots that can be affixed to windows.  Both businesses and homeowners have seen substantial reduction in bird collisions with such films installed.

Bird collisions are not a new problem but is one that wasn’t really taken seriously until at least the 1970s.  There isn’t much to be done about the greatest threat to birds – namely cats – but how buildings are constructed and operated is something we can control.

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As Bird Kills from Buildings Mount, Cities Look for Solutions

Photo, posted December 24, 2017, courtesy of Nicolas Vollmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Farming the frozen north

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Agriculture is the primary cause of land-based biodiversity loss.  As the global population grows, agricultural production needs to keep pace.  Estimates are that production needs to double by 2050.  How this can be accomplished without doing further harm to the environment and biodiversity is extremely challenging.

Climate change adds further complications to the challenge.  As the climate warms in the middle latitudes, agricultural zones may need to shift northward to regions which have evolved to have more suitable climates.  This represents a very real threat to the wilderness areas of Canada, Russia, and Scandinavia.  These places represent a significant fraction of the world’s wilderness areas outside of Antarctica.

According to researchers at the University of Exeter in the UK, if the forces driving climate change are not diminished, over the next 40 years warming temperatures are expected to make more than 1 million square miles newly suitable for growing crops.  As cropland goes barren in areas that have warmed too much, northern wilderness could be turned over to farming.  The vital integrity of these valuable areas could be irreversibly lost.

The study, published in the journal Current Biology, also says that climate change will shrink the variety of crops that can be grown on 72% of the land that is currently farmed worldwide.  Given this situation along with the rising global population, it is essential that land be used more efficiently.  We can feed a larger population from the farmland we already have, but people need to reduce meat consumption, cut food waste, and grow crops suited to their local climate.

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Warming Could Make Northern Wilderness Ripe for Farming, Study Finds

Photo, posted September 7, 2016, courtesy of Scott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Who wins: Wind or solar?

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A new study by the University of Exeter in the UK suggests that the world may have crossed a tipping point that will inevitably make solar power our main source of energy.  This data-driven model of technology seems to fly in the face of the current situation in which wind power contributes considerably more generation than solar power – by a factor of 3 in the U.S. and nearly double worldwide.

Wind and solar power both have advantages and disadvantages.  Solar power is quiet, requires little maintenance, and presents little danger to wildlife.  It is also practical for individual homes.  Residential wind power is not really a viable option for most people in most places.  But on the other hand, wind energy can produce more power than solar, can work both day and night, and can be located offshore far away from people.  On land, both wind and solar power take up lots of space and compete with other land use needs as well as countering people’s aesthetic preferences.

Both technologies continue to get cheaper over time, although solar has especially seen significant cost reductions.  The cost of solar power, which is already the cheapest form of electricity production, is estimated to fall to as low as $20 per megawatt hour over time from the current level of $40 per megawatt hour.

Wind and solar energy are on track to account for more than a third of the world’s electricity by 2030, according to the Rocky Mountain Institute.  Despite the predictions of various studies and the ambitions of specific technologies, it seems likely that wind and solar power will both play an expanding role in our energy systems for a long time to come.

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World may have crossed solar power ‘tipping point’

Photo, posted November 22, 2008, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar thermochemical hydrogen

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For decades, there has been talk of the hydrogen economy in which hydrogen would take the place of fossil fuels in a wide range of domestic and industrial applications.  Over time, hydrogen’s potential advantages in some applications have diminished but it is still seen as perhaps the most promising way to decarbonize long-distance truck, ship, and plane transportation as well as many heavy-duty industrial processes.

Hydrogen is the most common element in the universe, but here on Earth, it is tightly bound up in chemical compounds, notably water and hydrocarbons.  Extracting hydrogen from these compounds takes lots of energy.  To date, most hydrogen is produced from fossil fuel sources, resulting in carbon dioxide emissions.  So-called green hydrogen is made by splitting up water into its component elements.

Getting hydrogen from water generally uses electrolysis, which requires lots of electrical power.  That is why it isn’t the standard way to produce hydrogen; it costs too much to pay for all that power.

MIT scientists have been developing a process to make solar thermochemical hydrogen, or STCH.  STCH uses the sun’s heat to split apart water and no other energy source.  An existing source of solar heat drives a thermochemical reaction in which a heated metal surface grabs oxygen from steam and leaves hydrogen behind.  MIT did not invent the concept; their efforts are to make it practical.

Previous STCH designs were only capable of using 7% of incoming solar heat to make hydrogen.  The MIT process may be able to harness up to 40% of the sun’s heat and therefore generate far more hydrogen. 

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MIT design would harness 40 percent of the sun’s heat to produce clean hydrogen fuel

Photo, posted August 23, 2017, courtesy of Evan Lovely via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Too hot for people

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The effort to mitigate the effects of climate change has a goal of keeping the global temperature increase below 1.5 degrees Celsius above preindustrial levels.  To date, the average global temperature has increased by more than 1 degree.  We hear about rising sea levels, powerful storms, and various other alterations in climate and weather patterns.  A new interdisciplinary study by three institutions looked at the impact of surpassing the 1.5-degree level upon people being able to withstand heat and humidity.

Humans can only withstand certain combinations of heat and humidity before their bodies begin to experience heat-related health problems such as heat stroke and heart attacks. 

In human history, temperatures and humidity that exceed human limits have been recorded only a limited number of times and only for a few hours at a time, in the Middle East and Southeast Asia.

According to the new study, if global temperatures increase by 2 degrees Celsius above preindustrial levels, the 2.2 billion residents of Pakistan and India’s Indus River Valley, the one billion people living in eastern China, and the 800 million residents of sub-Saharan Africa will annually experience many hours of heat surpassing human tolerance.

If the warming continues further to 3 degrees, heat and humidity levels that surpass human tolerance would affect the Eastern Seaboard and the middle of the US from Florida to New York and from Houston to Chicago.

The worst heat stress will occur in regions that are not wealthy and that are experiencing rapid population growth.  But even wealthy nations will not escape from the expansion of conditions that are too hot for people.

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Climate-driven extreme heat may make parts of Earth too hot for humans

Photo, posted June 28, 2018, courtesy of Ivan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Disappearing snow crabs

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Alaska snow crabs are a cold-water species found off the coast of Alaska in the Bering, Beaufort, and Chukchi Seas. They are one of ten commercially-fished species in Alaskan waters. The perils of crab fishing in this region have been well documented for many years in the reality TV series Deadliest Catch.

Last year, officials in Alaska canceled the winter snow crab season for the first time ever due to a sharp population decline. While the number of juvenile snow crabs was at record highs just a few years earlier, approximately 90% of snow crabs mysteriously disappeared ahead of the 2021 season. 

This year, officials in Alaska have once again canceled the snow crab harvest season for the second year in a row, citing the overwhelming numbers of crabs – in the billions – missing from Alaskan waters. 

Scientists have suspected that the warming ocean temperatures triggered this snow crab population collapse.  But did the crabs move someplace else or die off?  According to a new study recently published by scientists at the National Oceanic and Atmospheric Administration, warmer ocean temperatures likely caused the snow crabs to starve to death.  The research team found a significant link between recent marine heat waves in the eastern Bering Sea and the sudden disappearance of the snow crabs that began showing up in surveys in 2021.

According to the study, warmer ocean water dramatically increases snow crabs’ caloric needs. But with the warmer water also disrupting much of the region’s food web, snow crabs had a hard time foraging for food and weren’t able to keep up.

Researchers expect the population may eventually find refuge in colder waters further north.

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Climate Change And Crabs

Billions of crabs went missing around Alaska

Photo, posted August 28, 2013, courtesy of Boris Kasimov via Flickr.

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Coffee, cocoa, and pollinators

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Multiple forces have been at play that have been detrimental to pollinators including climate change, land use change, pesticide use, and more.  There have been substantial declines in both the abundance and diversity of insect pollinators.  There is increasing public awareness of this issue, but it hasn’t really risen all that high among many people’s concerns.

A new study by University College London looked at the effects of the global decline in pollinators on thousands of crop-growing sites around the world involving thousands of insect pollinator species.

About 75% of all crops grown depend on pollinators to some degree.  The UCL research created a model that looks at which pollination dependent crops are most threatened over the next 30 years in order to provide a warning to both the agricultural and conservation communities.

The research indicates that the tropics are likely to be most at risk with regard to reduced crop production caused by pollinator losses.  This is mostly due to the interaction of climate change and land use.  The risks are highest in sub-Saharan Africa, northern South America, and southeast Asia.

These areas are where the world gets most of its coffee and cocoa, two crops that are near and dear to most of us.  These crops, as well as others such as mangoes, play vital roles in both local economies and global trade and reducing them could lead to increased income insecurity for millions of small-scale farmers in these tropical regions.

If pollinator loss isn’t high up on your list of global concerns, perhaps you should think about it next time you have a cup of coffee or enjoy some chocolate.

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Coffee and cocoa plants at risk from pollinator loss

Photo, posted May 23, 2013, courtesy of McKay Savage via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wild pigs in the U.S.

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In the U.S., there are as many as nine million feral swine living in 38 states.  A conservative estimate indicates that they cause about $1.5 billion in property and agricultural damage each year in this country. 

Pigs were introduced to the United States centuries ago as a food source, but they quickly established wild populations. Feral domestic pigs bred with purebred Eurasian boar that were introduced for hunting, and these hybridized wild pigs spread across the landscape thanks to their prolific reproductive rates and willingness to eat just about anything.

When wild pigs forage, they upturn roots and soil with their snouts, damaging natural habitats and other animals. A 2021 study found that wild pigs are releasing over five million tons of carbon dioxide annually by uprooting carbon trapped in soil. 

As a result, many programs were implemented nationwide to try to reduce populations, usually through lethal methods. 

According to new research from the University of Georgia’s Savannah River Ecology Laboratory and Warnell School of Forestry and Natural Resources, recent conservation efforts have proven effective at controlling wild pig populations in the Southeastern U.S.  Within 24 months of the start of control efforts in the study area in South Carolina, the research team found a reduction of about 70% in relative abundance of pigs, and a corresponding decline in environmental rooting damage of about 99%.

Wild pigs are basically a human-caused problem, and controlling their populations will require continued cooperation and collaboration. 

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Wild pig populations in U.S. can be managed

Wild Pigs And The Environment

Photo, posted January 28, 2013, courtesy of Don and Janet Beasley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The end of a supergiant iceberg

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In 2017, a supergiant iceberg known as A-68 calved from the Larsen C ice shelf in Antarctica. In 2020, it drifted close to South Georgia, a British island in the South Atlantic Ocean, and then began to break up.  This iceberg was enormous – nearly the size of Delaware.  When it started to break up, it released huge quantities of fresh, cold meltwater in a relatively small region.

Scientists from the British Antarctic Survey and the University of Sheffield have studied how the melting iceberg has affected the temperature and the salinity of the ocean surface in the area.  They found that the water near the surface was 8 degrees Fahrenheit colder than normal and the water only had about two-thirds of its normal saltiness.

The effects from the melted iceberg eventually extended well beyond South Georgia as the colder, less-salty water was carried by ocean currents to form a long plume that stretched more than 600 miles across the South Atlantic.  It also took several months to disappear.

The calving of this massive iceberg provided a unique opportunity for scientists to study the impact of iceberg melting on surface ocean conditions.  A-68 was one of the largest and most studied of all icebergs.  The study has shown that each individual melting giant iceberg can have widespread and long-lasting impacts on ocean conditions, which has consequences for the plant and animal life that lives there.

Climate change is likely to lead to more giant iceberg calving in the future.  It is important to monitor these events to assess their future impacts on ocean circulation, biology, and even seafloor geology.

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Supergiant iceberg makes surrounding ocean surface colder and less salty

Photo, posted October 24, 2018, courtesy of Jefferson Beck / NASA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megafires and ecosystems

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Wildfires are a natural phenomenon.  They have occurred long before there were people around.  Ecosystems adapt to fires and some species can benefit from them or even depend upon them.  But in recent times, fires have been intensifying and increasing in frequency and they are beginning to outstrip nature’s ability to bounce back from them.

So-called megafires – ones that dwarf typical wildfires in size – have an immediate ecological toll.  They kill individual plants and animals that might have survived smaller fires. 

Over millennia, many species of plants and animals have evolved to adapt to periodic fires.  They are especially sensitive to smoke and take protective action in a timely fashion. Others take advantage of food sources that arise when trees burn.

But even species that capitalize on burned-out areas of forests require oases of healthy woodland for at least part of their activities.  When fires are too widespread, such oases are too few and far between.

Animals that survive fires must find food, water, and shelter in the aftermath.  And all air-breathing animals are going to be impacted by smoke exposure because the chemicals in smoke are toxic to them as well as to people.

In places like Canada’s Northwest Territories, repeated fires have transformed some forests, eliminating dominant tree species and replacing them with others whose light seeds were carried on the wind.

Scientists have estimated that increased global fire activity could push more than 1,000 threatened plant and animal species closer to extinction.  Changing fire patterns are transforming landscapes and utterly remaking ecosystems.

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How Megafires Are Remaking the World

Photo, posted December 19, 2022, courtesy of Brian Pippin/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastics and agriculture 

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Once celebrated as a symbol of modern innovation, plastic is now both a blessing and a curse of our time.  Since the 1950s, more than nine billion tons of plastic have been produced, and 50% of that has been during the past 15 years.  Plastic is ubiquitous in every sector, and agriculture is no different.

Modern agriculture is responsible for almost a third of global greenhouse gas emissions and is a major drain on the planet’s resources.  Modern agriculture is also inextricably linked to plastic. In fact, more than 13 million tons of plastic are used in agriculture every year.  It’s nearly impossible to imagine modern agriculture without plastics. 

But according to a new study led by researchers from Rutgers University, plastic use in agriculture must be reduced in order to mitigate pollution, and prevent toxic chemicals from leaching into the soil and adversely affecting human health. 

In the study, which was recently published in Nature Communications Earth & Environment, the researchers found that it is essential to adopt a strategic approach to mitigate plastic pollution in agriculture, including responsible usage, reduction, efficient collection, reuse, and the implementation of innovative recycling methods. 

According to the researchers, when these sustainable approaches aren’t possible, biodegradable and nontoxic bioplastics should be used.  The research team insists that environmentally benign additives should be mandated in order to reduce plastic toxicity. 

Plastic pollution is a problem that needs to be addressed in every sector. 

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Plastic Use in Agriculture Must be Reduced, According to New Research

How can the use of plastics in agriculture become more sustainable?

Photo, posted November 12, 2022, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Geoengineering could create winners and losers

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Geoengineering – deliberate interventions to alter the climate and curb climate change – is a controversial topic, to say the least.  Once practically considered taboo even to discuss, there in increasing interest in at least exploring various ideas about how to halt or reverse climate change through direct actions that impact global temperatures.

Putting aside the very real concerns about the risks and dangers associated with such action, there is also the issue that climate interventions may create dramatically different effects across the globe, benefitting some areas and adversely affecting others.

A recent study by scientists at Rutgers University tackled this very issue.  Published in the journal Nature Food, it described the results of computer models simulating the impacts of stratospheric aerosol intervention (SAI), which is spraying sulfur dioxide into the stratosphere, where it would partially shield the Earth from the Sun, lowering temperatures.

The study looked at 11 different SAI scenarios and found that none of them benefitted everyone.  Uncontrolled global warming favors crop production in cold, high-latitude areas such as Canada, Russia, Scandinavia, and our northern border states.  Moderate amounts of SAI favors food production in the mid-latitudes (such as in the US and Europe.)  Large amounts of intervention favors agricultural production in the tropics. 

Even if geoengineering might not have dire consequences – which is by no means certain – it would create winners and losers.  Nations may have different ideas of what constitutes an optimal global temperature.  So, who gets to decide where to set the global thermostat?  The prospects for conflict loom large. 

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Climate Intervention Technologies May Create Winners and Losers in World Food Supply

Photo, posted November 18, 2021, courtesy of Conall 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...)