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Antibiotics In Animal Agriculture | Earth Wise

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In animal agriculture, farmers use antibiotics to treat, prevent, and control animal diseases, and to increase the productivity of their operations.  According to the FDA, approximately 80% of all antibiotics sold in the U.S. are purchased for use in food-producing animals. 

The routine administration of antibiotics to farm animals for non-therapeutic purposes promotes the development of antibiotic-resistant bacteria, with repercussions for human and animal health.  As antibiotic-resistant bacteria spreads, medicines used to treat human diseases can become less effective. 

According to a new study led by researchers from the University of Washington, a California policy restricting the use of antibiotics in farm animals is associated with a reduction in one type of antibiotic-resistant infection in people in the state.  The findings, recently published in the journal Environmental Health Perspectives, suggest that regulations limiting the use of antibiotics in livestock can significantly impact human health. 

In 2018, California Senate Bill 27 banned routine preventive use of antibiotics in food-animal production and any antibiotic use without a veterinarian’s prescription.  Last year, the European Union passed a law restricting antibiotic use to only sick animals on farms.  And coming this June, most antibiotics – those that are medically important to humans and animals – will be by prescription only in the United States.  

Despite these changes, antibiotic resistance is projected to remain one of the biggest threats to human health over the next 50 years because resistance continues to grow and few new antibiotics are coming online. 

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Restricting antibiotics for livestock could limit spread of antibiotic-resistant infections in people

Ranchers should prepare now for 2023 animal antibiotic guidelines

Photo, posted May 8, 2018, courtesy of Preston Keres / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Humanity Weighs On The World | Earth Wise

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There are countless ways in which humankind has had disproportionate effects on our planet and most of those effects have been negative.  A recent study led by the Weizmann Institute of Science in Israel looked at the total combined weight of various groups of mammals on Earth.  The results are that human beings and our domesticated mammals are the overwhelming majority of the total mass of mammals.

We think of large land mammals – elephants, bears, bison, wildebeests, and so on – as adding up to a massive amount of animal matter.  The study determined that all wild land mammals put together add up to about 22 million metric tons. Wild marine mammals – such as dolphins and whales – add up to about 40 million tons in total.  These sound like pretty big numbers until we look at the human and human-created side of the equation.

The study found that humans weigh about 390 million metric tons, while domesticated mammals – like sheep, cows, and pigs as well as dogs and cats – weigh about 630 million metric tons combined.

All told, wild mammals account for only 6% of all mammals by weight.   People and their domesticated animals make up the other 94%.  This enormous imbalance is an indication of how profoundly humans have reshaped life on Earth.  House cats total twice the weight of African elephants and pigs add up to twice the weight of all wild land animals combined.

The conclusion to draw from the big picture here is that wild animals on Earth are not doing very well.  We already knew this from many other perspectives, but this census by weight presents a stark picture of the extent to which we have taken over the planet and its ecosystems.

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Total Weight of Wild Land Mammals Less Than One-Tenth Weight of All Humans

Photo, posted December 27, 2006, courtesy of Nigel Hoult via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Dangers Of Melting Glaciers | Earth Wise

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Some of most dramatic evidence that the Earth’s climate is warming is the retreat and even disappearance of mountain glaciers around the world.  2022 was the 35th year in a row that glaciers tracked by the World Glacier Monitoring Service lost rather than gained ice.  Glaciers gain mass through snowfall and lose mass through melting and sublimation (water evaporating directly from solid ice.)  Some glaciers that terminate in lakes or the ocean lose mass through iceberg calving.

In the warming climate, glaciers retreat and meltwater collects at the front of the glacier forming a lake.  Such lakes can suddenly burst and create a fast-flowing Glacier Lake Outburst Flood that can spread over a large distance from the original site – in some cases over 70 miles.  These floods can damage property, infrastructure, and agricultural land and can also be deadly.

The number of glacial lakes has grown rapidly since 1990 as a result of climate change.  According to research by an international team of scientists led by Newcastle University in the UK, the number of people living in glacial lake catchments has increased significantly.

According to the study, 15 million people live within 30 miles of a glacial lake.  The highest danger is in High Mountain Asia – which encompasses the Tibetan Plateau.  That area, which spans from Kyrgyzstan to parts of China, has 9.3 million people potentially at risk.  India and Pakistan have around 5 million exposed people.

Detailed analysis shows that it is not the areas with the largest number or most rapidly growing lakes that are most dangerous.  It is the number of people in proximity to the lakes and their ability to cope with potential floods.

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Glacial flooding threatens millions globally

Photo, posted February 12, 2022, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic From Sunlight | Earth Wise

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Photosynthesis is the process that plants use to turn water, carbon dioxide, and energy from sunlight into plant biomass.  It provides humans and much of animal life with food.  Photosynthesis is also nature’s way of reducing the amount of carbon dioxide in the atmosphere.  The CO2 is not directly stored in plants but rather is combined into organic compounds.

Researchers across the globe are trying to find effective ways to mimic photosynthesis.  One version of artificial photosynthesis seeks to take carbon dioxide and combine it into organic compounds that can be used as raw materials for various kinds of manufacturing. 

A research team in Japan has found a way to synthesize fumaric acid from carbon dioxide using sunlight to power the process.  Fumaric acid is a chemical typically synthesized from petroleum and is used as a raw material for making biodegradable plastics such as polybutylene succinate. 

Much of artificial photosynthesis research is aimed at using solar energy to convert carbon dioxide directly into a fuel rather than a raw material.  Such solar fuels can be produced by a variety of means including thermochemical (using the sun’s heat to drive chemical reactions), photochemical (using the sun’s light to drive chemical reactions), and electrochemical (using solar-generated electricity to drive chemical reactions.)   These approaches generally involve the use of specialized catalysts to drive the desired chemical reactions. 

One way or another, what techniques for artificial photosynthesis have in common is trying to imitate what plant life on Earth has been doing for millions of years. 

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Artificial photosynthesis uses sunlight to make biodegradable plastic

Photo, posted June 14, 2017, courtesy of Alex Holyake via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects On The Menu | Earth Wise

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According to the World Food Programme, a record 349 million people across 79 countries are facing acute food insecurity.  This constitutes a staggering rise of 200 million people compared to pre-pandemic levels.  Nearly one million people globally are fighting to survive in famine-like conditions, which is ten times more people than just five years ago.  

As a result, many experts contend that alternative or so-called novel food sources – such as lab-grown meats, seaweed aquaculture, and insects – will be necessary to help fight global hunger and global food insecurity. 

Insects already form a significant part of diets in many cultures around the world.  Insects are great sources of nutrients, including protein, vitamins, and minerals.  But insects have yet to be embraced in any substantial way in western cultures… but that may be changing. 

In fact, the European Union has now certified four types of bugs as food fit for human consumption.  The larvae of lesser mealworms and house crickets recently became the third and fourth insects approved for sale as food in the EU, joining yellow mealworms and grasshoppers. Eight more applications are awaiting approval.

Insects are already a delicacy in many high-end restaurants around the world, and a normal and healthy part of diets in countries like Mexico and Thailand.  Embracing insects as a food of the future will not only help in the fight against global hunger, but will also help to reduce greenhouse gas emissions and to slow species extinction. 

In Western food markets, the so-called “yuck factor” remains the biggest hurdle to cross.  But as the world population grows, the need for sustainable solutions in the food industry grows with it. 

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Insects on the menu as EU approves two for human consumption

World Hunger Surged in 2020, U.N. Says

A global food crisis

Photo, posted April, 2014, courtesy of Shankar S. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Reef Insurance | Earth Wise

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Coral reefs around the world face multiple dangers from warming waters, acidification, human activity, and more.  Powerful storms often cause tremendous damage to reefs.  When possible, snorkelers and divers are deployed to try to repair damage to reefs.  But philanthropy and government grants are basically the only resources available to fund such actions.

Three years ago, tourist businesses and the government in the Mexican state of Quintana Roo purchased an insurance policy to offset costs of protecting the local parts of the Mesoamerican Reef.  The environmental group the MAR Fund later took out an insurance policy on the rest of the reef in Mexico, Belize, Guatemala, and Honduras. 

With this precedent, the Nature Conservancy recently purchased an insurance policy on behalf of the state of Hawaii to help offset repair work on its coral reefs.  It is the first U.S. coral insurance contract.

Coral reefs are more than just hosts for marine life.  They provide barriers against ocean storm surges, which is a major financial incentive for protecting them and hence an incentive to invest in insurance.

The new Hawaiian insurance policy has a premium of $110,000 a year and will provide $2 million in protection.  Payouts occur when wind speeds go above 50 knots.  No further proof of damage is required.

The Nature Conservancy has created teams called ‘Reef Brigades’ composed of snorkelers and divers who recover reef fragments, store them in ocean or shore-based nurseries, and then re-attach them when conditions are safe.  It can be very expensive to do this sort of work, particularly when new corals grown in a nursery are required.

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Analysis: First U.S. coral insurance marks the rise of the reef brigades

Photo, posted September 14, 2011, courtesy of Greg McFall/NOAA Office of National Marine Sanctuaries via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tick-Borne Pathogens In Canada | Earth Wise

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Measuring only three to five millimeters in size, tiny ticks are a big problem.  They are widely distributed in many parts of the world, especially in warm and humid climates.  Ticks are arachnids – not insects – meaning they’re more closely related to spiders than to flies or mosquitos.  They are external parasites that feast on the blood of birds, reptiles, amphibians, and mammals – including humans.

In the United States, ticks are responsible for spreading potentially life-threatening infectious diseases.  According to estimates from the Centers for Disease Control and Prevention, ticks infect more than 300,000 people with Lyme disease in the U.S. every year, and the numbers continue to rise.  Other common tick-borne diseases include anaplasmosis, babesiosis, Rocky Mountain Spotted Fever, and powassan encephalitis.

Ticks are becoming a problem in Canada as well.  According to a new study by researchers from McGill University and the University of Ottawa, tick-borne pathogens are on the rise in Central Canada – a region where ticks were never previously detected. 

In the study, the researchers collected ticks across Ontario and Quebec.  They found that five emerging pathogens were present across their study sites, including the pathogens that cause Lyme disease and babesiosis.  The researchers also found that pathogens can transmit in different ways.  Typically, pathogens are transmitted to a tick after feeding from the blood of an infected host, like a small mammal.  But the research team found evidence of pathogens that could be directly transmitted from adult female ticks to larval ticks.

According to the researchers, more comprehensive testing and tracking is needed to detect the spread and risks of tick-borne pathogens to humans and wildlife in Canada.

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Tick-borne pathogens increasingly widespread in Central Canada

Photo, posted May 4, 2009, courtesy of Jerry Kirkhart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

It Really Is Greenhouse Gases | Earth Wise

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The scientific consensus that human-generated carbon dioxide is changing the climate began to form in the 1980s. 

For a long time, the changes to the climate were simply denied.  After a while, as those changes became increasingly hard to ignore, the argument shifted to the changes being real but not caused by anything people are doing.  The multi-trillion-dollar fossil fuel industry was strongly motivated to focus attention away from the association between carbon dioxide and climate change.

The greenhouse gas effect has been known since the 19th century.  It isn’t just real; it is essential to life on earth.  Without sufficient levels of carbon dioxide in the atmosphere to trap some of the sun’s heat, the earth would be an ice planet incapable of supporting much in the way of life.  But there can be too much of a good thing.

Naysayers continue to grasp at alternative explanations for the warming planet rather than the inconvenient truth.  Some people try to claim that it is the release of heat from all our energy-generating activities -power plants, heaters and air conditioners, vehicles, and so on – that is warming the planet.

That issue has been studied in detail.  Human activity does generate a lot of heat and, technically speaking, that heat does help warm the planet.  However, the sun dumps 10,000 times more heat on the earth than all of human energy production added together.  Just the normal fluctuations in solar energy are 10 times larger than everything we do put together.

What is increasingly warming the planet is not the continuing energy striking the earth; it is primarily the fact that growing levels of greenhouse gases in the atmosphere are trapping more and more of that heat and preventing it from escaping into space.

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Integrating anthropogenic heat flux with global climate models

Photo, posted August 25, 2009, courtesy of Gerald Simmons via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Renewable Energy Booming in India | Earth Wise

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India is the country with the second largest population in the world – over 1.4 billion people – second only to China – and will undoubtedly pass China soon based on population trends in the two countries.   India is the third largest emitter of carbon dioxide, after China and the U.S.  With its rapidly growing population and an economy heavily dependent on coal and oil, emissions in India are on a steep upward trajectory.  Currently, fossil fuels account for about 60% of India’s installed energy capacity.  It is essential that actions are taken to curb its rapid increase in greenhouse gas emissions.

To that end, India’s renewables sector is booming.  The country is projected to add 35 to 40 gigawatts of renewable energy each year until 2030.  That’s enough energy to power up 30 million more homes each year.  The country has established a target of producing 50% of its electricity from non-fossil fuel sources by the end of this decade.

 India is expected to reach over 400 gigawatts of renewable energy capacity by 2030

according to the Institute for Energy Economics and Financial Analysis and Climate Energy Finance.  The Indian government’s own projections estimate that the country will reach 500 gigawatts of renewable capacity in that timeframe.

As is the case with China, a country with an enormous population undergoing major economic growth and modernization has vast energy needs.  While it is imperative for the entire world that India puts a cap on its growing greenhouse gas emissions, it is a difficult challenge for an energy-hungry country.

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Renewable energy booms in India

Photo, posted November 14, 2011, courtesy of Amaury Laporte via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moving Endangered Species | Earth Wise

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People have intentionally or accidentally introduced numerous invasive species to habitats around the world.  At the same time, the planet’s wildlife is in a steep decline.  A recent study estimated that the populations of over 5,000 vertebrate species have declined by an average of nearly 70% since 1970.  A United Nations report warns that human activity has threatened as many as a million species with extinction.

With all of this as a background, there is climate change that is altering the habitats of the world’s species – warming lakes and oceans, turning forests into grasslands, tundra into woodland, and melting glaciers.  In response to these changes, living things are rearranging themselves, migrating to more hospitable locations.  But many species are just not capable of finding more suitable habitats on their own.

Conservationists are now increasingly considering the use of assisted migration. In some cases, when a species’ critical habitat has been irreversibly altered or destroyed, agencies are establishing experimental populations outside of the species’ historical range.  Such actions are often deemed extreme but may be increasingly necessary.

However, clear-cut cases are relatively rare.  More likely, it is a more difficult judgement call as to whether assisted migration is a good idea or is possibly a threat to the ecosystem of the species’ new location.  The relative dearth of assisted migration experiments is less likely a result of legal barriers than it is a lack of scientific and societal consensus on the practice. Scientists are now trying to develop risk-analysis frameworks that various agencies can use in considering potential assisted migration experiments. 

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Last Resort: Moving Endangered Species in Order to Save Them

Photo, posted March 18, 2010, courtesy of Jean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mosquito Magnets | Earth Wise

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We’ve all probably had the experience of being in the great outdoors with other people and having some of them being nearly devoured by mosquitoes while others didn’t get bitten at all.  It seemed like some people are mosquito magnets while others just aren’t the insects’ cup of tea, so to speak.

There have been various theories proposed over the years including such things as it being a question of blood type, or it having to do with how close one’s blood vessels are to their skin surface.

A new study by the Howard Hughes Medical Institute and the Rockefeller University has uncovered what appears to be the real explanation.  According to the paper published in the journal Cell, certain body odors are the deciding factor.  Every person has a unique scent profile associated with different chemicals present on their skin.  The researchers found that people whose skin produces high levels of carboxylic acids are the most attractive to mosquitos.

The researchers collected scent samples from participants by having them wear silk stockings on their arms for six hours.  The nylons were then cut into pieces and the pieces exposed to mosquitos.  After several months of head-to-head battles between various nylon samples, the study clearly demonstrated that the samples from subjects with higher levels of carboxylic acids in the skin were far more attractive to mosquitos.

Humans produce the substance at much higher levels than other animals.  There is little one can do about their own levels.  Changing one’s diet or what soap they use doesn’t seem to make a difference. 

Perhaps researchers can come up with some method of breaking down carboxylic acids in the skin in the future.  Until such time, there are really people who are mosquito magnets.

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Some People Really Are Mosquito Magnets, and They’re Stuck That Way

Photo, posted September 4, 2014, courtesy of James Gathany / Centers for Disease Control via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Food Waste And The Environment | Earth Wise

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It is tragic that 31% of the world’s food production goes uneaten.  About 14% isn’t distributed after it is harvested.  Another 17% ends up wasted in retail or by consumers.  Worldwide, the amount of food that is wasted is enough to feed more than a billion people while at least 828 million people continue to be affected by hunger.  To make matters worse, food waste accounts for 8 to 10% of global greenhouse gas emissions, which is at least double that of aviation.  Food waste, rotting away in landfills, produces methane gas, a major source of global warming.

Around the world, there are efforts being launched to try to improve the situation.  California now has a law that requires grocery stores to donate edible food that would otherwise be disposed of or they face fines.  The state’s cities and counties are required to reduce the amount of organic waste going into landfills by 75% by 2025 and compost it instead.

In London, grocers no longer put date labels on fruits and vegetables because the labels were leading people to trash perfectly good food.  France now requires supermarkets and large caterers to donate food that is still safe to eat.

South Korea has little space for landfills.  So, the country has been campaigning against throwing away food for 20 years.  Nearly all organic waste in the country is turned into animal feed, compost, or biogas.  Koreans even have to pay for throwing out food waste.  There are now trash bins equipped with electronic sensors that weigh food waste.

All of these things can help.  There is no single magic bullet for reducing food waste, but it is essential to do for so many reasons.

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Inside the Global Effort to Keep Perfectly Good Food Out of the Dump

Photo, posted November 30, 2020, courtesy of Marco Verch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Better Way To Recycle Plastics | Earth Wise

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The global accumulation of plastic waste is an ever-growing problem.  At least five billion tons of the stuff has accumulated on land and sea and is even showing up in the bodies of animals and humans.  Recycling plastic instead of making even more of it seems like an essential thing to do but it has proven to be extremely challenging.

The main problem is that plastics come in many different varieties and the ways of breaking them down into a form that can be reused are very specific to each type of plastic.  Sorting plastic waste by plastic type is extremely impractical at large scale.  Certainly, most consumers can’t do it themselves.  As a result, most plastic gathered in recycling programs ends up in landfills.

New research at MIT has developed a chemical process using a catalyst based on cobalt that is very effective at breaking down a variety of plastics, including polyethylene and polypropylene, which are the two most widely produced plastics.   The MIT process breaks plastics down into propane.  Propane can be used as a fuel or as a feedstock for making many different products, including new plastics.

Plastics are hard to recycle because their long-chain molecules are very stable and difficult to break apart.  Most chemical methods for breaking their chemical bonds produce a random mix of different molecules which would somehow have to be sorted out in order to be useful for anything.

The new process uses a catalyst called a zeolite that contains cobalt nanoparticles.  The catalyst selectively breaks down various plastic polymer molecules and turns more than 80% of them into propane.

The researchers are still studying the economics and logistics of the method, but it looks quite promising.

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New process could enable more efficient plastics recycling

Photo, posted April 25, 2016, courtesy of NOAA Coral Reef Ecosystem Program via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tepary Beans | Earth Wise

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Tepary beans are an ancient crop native to the northern part of Mexico and the southwestern part of the U.S..  They have been grown in those places by native peoples since pre-Columbian times.  They are still grown in Native American reservations in Arizona’s Sonoran Desert.  One can purchase them from some small farms in that region. 

What sets tepary beans apart from other beans is that they are among the most drought- and heat-tolerant legume crops in the world.  They can be grown without irrigation under conditions that are not viable for other crops.  They can be consumed by people like many other kinds of beans, and they can also provide forage for livestock with better nutrition content than many other plants.  They seem to be a very attractive option for a crop in the changing climate.  What is lacking, at present, is large supplies of tepary seeds to be planted.

Researchers at Texas A&M have been funded to bring tepary beans into modern cropping systems and diets.  The goal is to develop tepary bean cultivars with high biomass and yield that are still well-suited to drought and heat conditions.  Getting the beans to the point of widespread commercialization will take several years.  The end result should be of interest to pulse growers, seed industries, and food companies across the U.S.

Tepary beans are higher in fiber and protein than most other beans.  They come in several different colors, each of which has unique flavor and texture characteristics.  The white ones have a naturally sweet flavor.   The brown beans are slightly nutty in flavor and are similar to pinto beans.  If the Texas program is successful, we may all be eating tepary beans some day.

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Tepary Beans Offer Producers A Low-Input, Climate-Resilient Legume Alternative

Photo, posted August 25, 2017, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What Is Healthy Soil? | Earth Wise

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Soil supports life by providing many critical ecosystem services.  For example, soil acts as a water filter, a growing medium, and provides habitat for billions of organisms.  Soil is also the foundation of our cities and towns, and the basis of global agroecosystems, which provide humans with feed, fiber, food, and fuel.

For all of these reasons and many more, having healthy soil is vital.  But what does soil health mean? And how should it be measured?

According to new analysis by researchers from Cranfield University and Nottingham University in the U.K., how we think about, measure, and study soil must change in order to better understand how to manage this resource effectively. 

While the term ‘soil health’ is widely used, it means different things to different people.  There is no single agreed upon way to gauge the overall health of soil. 

Current approaches to assess soil health measure individual soil properties and use findings  to assign a single number giving an overall score.  But according to the research team, this does not reflect the wider system perspective that’s needed to fully evaluate the health of soil over time.

Instead, the researchers propose a new system to assess soil health based on a hierarchical framework that takes in several measures, including signs of life, signs of function, signs of complexity, and signs of emergence, which is the extent to which soils recover from multiple stressors. 

This new approach, which can be applied to all soils, moves us closer to an interdisciplinary understanding of the whole picture of soil health.  After all, healthy soil is fundamental to our survival.

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We need to change how we think about soil

Photo, posted April 8, 2008, courtesy of Brian Boucheron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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.

Saving Lives With Air Conditioning | Earth Wise

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This summer, extreme heatwaves struck the United States, Europe, and Africa.  Thousands of people died as a result.  In July, the impact of extreme heat in places ill-prepared for it was evident.  In the U.K., where air conditioning is uncommon, public transportation shut down, schools and offices closed, and hospitals cancelled non-emergency procedures.

Air conditioning, which we mostly take for granted in this country, is a life-saving tool during extreme heat waves.  However, only about 8% of the 2.8 billion people living in the hottest – and often poorest – parts of the world have AC in their homes.

A new study at Harvard modeled the future demand for air conditioning as the number of days with extreme heat continues to increase across the globe.  The researchers identified a massive gap between current AC capacity and what will be needed by 2050 to save lives, particularly in low-income and developing countries.

If the rate of greenhouse gas emissions continues on its present course, the study concluded that that at least 70% of the population in several countries will require air conditioning by 2050.  The number will be even higher in equatorial countries like India and Indonesia.  At this point, even if the goals of the Paris Climate Accords are met, an average of 40-50% of the population in many of the world’s warmest countries will still require AC.

The research looked at various scenarios.  One in which emissions continue to increase leads to widespread need for air conditioning even in temperate countries.  In Germany, 92% of the population would need it, and here in the U.S., 96% would need it.

Planning for future power systems must take into account the essential needs of a warming world.

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In a hotter world, air conditioning isn’t a luxury, it’s a lifesaver

Photo, posted July 24, 2021, courtesy of Phyxter Home Services via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

North American Birds And Climate Change | Earth Wise

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Most plants and animals live in areas with specific climate conditions, such as rainfall patterns and temperature, that enable them to thrive. Any change in the climate of an area can affect the plants and animals living there, which in turn can impact the composition of the entire ecosystem.   

As such, the changing climate poses many challenges to plants and animals.  For example, appropriate climatic conditions for many species are changing.  As a result, some may even disappear altogether.  These problems can be compounded when the climate is changing in tandem with other human-caused stressors, such as land use change.

When there is increasing divergence between suitable climatic conditions for a particular species and its abundance and distribution through time, this is known as climate decoupling.

According to a new study recently published in the journal Nature Ecology & Evolution, some species of North American birds have not fully adjusted their distributions in response to climate change.  The areas where these birds live have become more decoupled from their optimal climate conditions.  Climate decoupling as a result of ongoing climate change could lead to additional stressors on many bird species and exacerbate bird population declines.

In the study, the research team analyzed data on bird population changes through time from the North American Bird Survey.  They found that at least 30 out of 114 species (or 26%) of North American birds have become less well adjusted to their climate over the last 30 years. This means that their distributions and abundances were increasingly decoupled from climate over time.

The researchers also found that the overall trend of climate decoupling shows no signs of slowing down. 

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North American birds not fully adjusting to changing climate

Photo, posted July 16, 2016, courtesy of Kelly Azar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Environmental DNA | Earth Wise

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Marine protected areas are sections of the ocean where governments place limits on human activity.  They are intended to provide long-term protection to important marine and coastal ecosystems.  MPAs are important because they can protect depleted, threatened, rare, and endangered species and populations.

In January 2020, the Republic of Palau in the western Pacific Ocean created one of the world’s largest marine protected areas.  The Palau National Marine Sanctuary covers 80% of the country’s economic zone and prohibits all extractive activity like fishing and mining over a 183,000 square mile area in order for the island nation to ensure its food security and grow its economy in the face of climate change.

The Marine Sanctuary is an ambitious enterprise.  The question is how Palau can evaluate whether and how well it is working?

A team of scientists from Stanford University and Palau-based colleagues are making use of Environmental DNA – or eDNA – technology to monitor the large-scale marine protected area.  eDNA is the cells, waste, viruses, and microorganisms that plants and animals leave behind.  Samples of marine eDNA effectively provide a fingerprint of the organisms that have recently passed through the water in a given area.  This gives scientists a way to assess an ecosystem’s biodiversity and keep track of the types of species inhabiting a specific area.  Using eDNA, it is possible to keep track of all the  organisms that live below the surface and learn about things we can’t even see.

The team has embarked on a program of periodic sampling of the waters off Palau and hope to be able to monitor the results of establishing the Marine Sanctuary.

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eDNA: Bringing biodiversity to the surface

Photo, posted June 12, 2013, courtesy of Gregory Smith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Less Phytoplankton In The Gulf Of Maine | Earth Wise

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Phytoplankton, also known as microalgae, are the base of the marine food web and also play a key role in removing carbon dioxide from the air.  They are eaten by primary consumers like zooplankton, small fish, and crustaceans. 

Phytoplankton, like land plants, absorb carbon dioxide from the atmosphere and use photosynthesis to grow.  Then they become a food source for other organisms and ultimately for people who depend upon marine ecosystems.   If phytoplankton productivity is disrupted, there can be adverse effects on regional fisheries and the communities that depend on them.

The Gulf of Maine is becoming warmer and saltier, because of ocean currents pushing warm water into the gulf from the Northwest Atlantic.  These temperature and salinity changes have led to a significant decrease in the productivity of phytoplankton.   According to a new paper from scientists at Bigelow Laboratory of Ocean Sciences in Maine, phytoplankton are about 65% less productive in the gulf than they were 20 years ago.

The study’s results come from the analysis of the Gulf of Maine North Atlantic Time Series, a 23-year sampling program of the temperature, salinity, chemical, biological, and optical measurements of the gulf.  The scientists refer to what they describe as a giant windmill effect happening in the North Atlantic, which is changing the circulation of water coming into the Gulf of Maine.  In the past, inflows from the North Atlantic brought water from the Labrador Current, which made the gulf cooler and fresher.  The new circulation is making the water warmer and saltier.

These changes have significant implications for higher marine species, fisheries, the lobster industry, and other activities in the states that border the Gulf of Maine.

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NASA-funded Study: Gulf of Maine’s Phytoplankton Productivity Down 65%

Photo, posted November 15, 2015, courtesy of Paul VanDerWerf 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...)