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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.

Living in a Carbon Bubble | Earth Wise

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The earth’s atmosphere is a little over 0.04% carbon dioxide, currently about 420 parts per million.  That’s more than it’s been in millions of years and is changing our climate.  But these levels of CO2 are not enough to directly affect people.

However, people are sensitive to the amount of carbon dioxide they are breathing.  It is actually an indoor pollutant.  High concentrations have been shown to reduce our cognitive performance, our health, and our comfort.  For example, a study in 2012 showed that performance in a variety of cognitive function tests was reduced by 12% when CO2 levels reached 1,000 parts per million and by 51% at 2,500 ppm.

How common are high levels of carbon dioxide?  Pretty common.  Offices often have CO2 levels of 600 ppm or higher, but 5% of US offices have average concentration about 1000 ppm and some conference rooms can reach 1900 ppm.  Classrooms often reach average levels above 1000 ppm.  Passenger aircraft have average levels around 1400 ppm during flight, and can peak over 4,000 ppm.  Cars with one occupant with the windows closed and the air recirculating have levels above 4,000 ppm. 

Where does it all come from?  From us.  We exhale CO2 and if we are in enclosed spaces with insufficient air circulation and ventilation, we end up living in a carbon dioxide bubble.  Most of us live with high CO2 levels – all day and every day.  It is a form of indoor pollution that has not gotten enough attention.

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I’m living in a carbon bubble. Literally.

Photo, posted October 24, 2013, courtesy of Cory W. Watts via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reshaping Our Planet | Earth Wise

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Human activity – especially agriculture – has altered 70% of the land on our planet.  According to a new report from the United Nations, damage to the Earth’s lands has put the planet on “crisis footing”.

Our health, our economy, and our well-being depend on land.  The food we eat, the water we drink, and the air we breathe all rely on status of the land to at least some extent.

According to the report, up to 40% of the planet’s land is already degraded, affecting half of the people alive today.  At current rates, an additional area nearly the size of South America will be degraded by 2050.

Degradation of land occurs in various ways, including deforestation, desertification, and the loss of wetlands or grasslands.  All of these things are caused by human activities.  As forests, savannas, wetlands, and mangrove swamps are converted to agriculture or are lost to urban expansion, greenhouse gas emissions rapidly increase, adding to the effects of climate change.  The climate crisis, biodiversity loss, and land degradation are integrally linked.

Much of the blame for degraded landscapes is on humanity’s ever-expanding need for food and the modern farming systems that produce it.  The global food system is responsible for 80% of the world’s deforestation, 70% of freshwater use, and is the greatest driver of land-based biodiversity loss.  Modern agriculture has altered the face of the planet more than any other human activity.

The report urges efforts at restoration of land.  Restoration can take multiple forms, including planting forests and shrubs or grazing livestock and growing crops between trees instead of clearing existing forests.

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UN Report Says Humanity Has Altered 70 Percent of the Earth’s Land, Putting the Planet on a ‘Crisis Footing’

Photo, posted June 20, 2010, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Pandas And Climate Change | Earth Wise

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Red pandas are small mammals native to the mountainous forests of China, India, Nepal, Bhutan, and Myanmar.  Unlike their name suggests, they are not related to giant pandas.  In fact, red pandas are distant relatives of raccoons. Renowned for their tree-climbing abilities, red pandas live at moderately high elevations in the Himalayas where they forage widely for bamboo shoots and various fruits.

According to the International Union for the Conservation of Nature, red pandas are endangered.  Scientists estimate that there are less than 10,000 red pandas remaining in the wild today, and these numbers are continuing to fall. 

Habitat loss is the main threat to red panda’s survival.  Human expansion into the area, combined with the effects of climate change, has led to the fragmentation and loss of livable land.  Red pandas also face dangers from hunting and poaching.

According to new research recently published in the journal Landscape Ecology, human impacts are driving red pandas closer to extinction than previously thought.  Using GPS telemetry, a research team from the University of Queensland in Australia tracked red pandas in Nepal over a 12-month period.  The researchers found that human activities, such as infrastructure development, were causing red pandas to restrict their movements, which is further fragmenting their habitat and interfering with natural interactions between the animals. 

As the amount of wild forest dwindles, red pandas are being forced into situations where they must decide whether to live closer to predators or adapt to co-exist with humans.

The research team recommends minimizing human-induced disturbances in red panda habitats and to maintain habitat continuity in ecologically sensitive areas. 

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Red pandas face a fractured future

IUCN: Red Panda

Photo, posted November 27, 2016, courtesy of Mathias Appel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon Dioxide Levels Higher Again | Earth Wise

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The National Oceanic and Atmospheric Administration reported that carbon dioxide levels measured in May at the Mauna Loa Observatory reached a value of 421 parts per million.  This is 50% greater than pre-industrial levels and is in a range not seen on earth for millions of years.

Before the Industrial Revolution, CO2 levels fairly steadily measured around 280 parts per million, pretty much for all 6,000 years of human civilization.  Since the Industrial Revolution began in the 18th century, humans have generated an estimated 1.5 trillion tons of CO2 pollution, much of which will continue to warm the atmosphere for thousands of years.

The present levels of carbon dioxide are comparable to those of an era known as the Pliocene Climatic Optimum, which took place over 4 million years ago. 

The bulk of the human-generated carbon dioxide comes from burning fossil fuels for transportation and electrical generation, from cement and steel manufacturing, and from the depletion of natural carbon sinks caused by deforestation, agriculture, and other human impacts on the natural environment.

Humans are altering the climate in ways that are dramatically affecting the economy, infrastructure, and ecosystems across the planet.  By trapping heat that would otherwise escape into space, greenhouse gases are causing the atmosphere to warm steadily, leading to increasingly erratic weather episodes ranging from extreme heat, droughts, and wildfires, to heavier precipitation, flooding, and tropical storm activity.

The relentless increase of carbon dioxide measured at Mauna Loa is a sober reminder that we need to take serious steps to try to mitigate the effects of climate change.

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Carbon dioxide now more than 50% higher than pre-industrial levels

Photo, posted December 20, 2016, courtesy of Kevin Casey Fleming via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Who Can Solve The Plastic Waste Problem? | Earth Wise

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Plastic packaging waste is a global problem.  It collects in the oceans, breaks down into microplastics, which are consumed by fish and in turn by people who eat the fish.  Only 14.5% of U.S. plastic waste is recycled.  Most of it ends up in landfills, where is remains undegraded for hundreds of years. 

A new international study explored the global patterns of plastic packaging waste.  The study found that three countries – the U.S., Brazil, and China – are the top suppliers of waste.  In terms of supply, the Americas generate 41% of the world’s production of plastic waste, Europe 24%, and Asia 21%.

That’s the plastics supply.  As far as the consumers actually creating waste are concerned, the Americas represent 36% of the world’s packaging consumption, Asia 26%, and Europe 23%.

Packaging high-protein food such as meat, fish, and dairy is a major contributor to the waste problem.  Plastic for this purpose is hard to replace and international exports exacerbate the problem, accounting for about 25% of plastic packaging waste.

International agreements typically focus on restrictions and fees on production.  But that mostly creates strong incentives to simply relocate polluting activities to developing countries, which is a zero-sum game.  There need to be incentives for consumers to reduce plastic use such as taxes on waste management, refunds on returning bottles, single-use plastic bans, and so on.

Who can solve the plastic waste problem?  Everyone along the supply chain as well as the final consumers have to be part of the solution for reducing plastic waste.

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Producers and consumers must share burden of global plastic packaging waste

Photo, posted March 29, 2022, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And The Next Pandemic | Earth Wise

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As the planet continues to heat up, animals big and small are moving towards the poles to escape the heat.  According to researchers, these animals are likely to come into contact with other animals that they normally wouldn’t, and are likely to relocate to regions with large human populations.  These factors create opportunities for pathogens to get into new hosts, which dramatically increases the risk of a viral jump to humans.  Climate change could lead to the next pandemic.      

An international research team led by scientists at Georgetown University recently made this connection between climate change and viral transmission.  In the study, which was recently published in the journal Nature, researchers conducted the first comprehensive assessment of how climate change will restructure the global mammalian virome.  Their work focused on geographic range shifts. 

As animals eccounter other animals for the first time, the study projects that they will share thousands of viruses.  And as animals increasingly move into the same areas as humans, there will be greater opportunities for these viruses to jump to humans.  The research team says that the impact on conservation and human health could be alarming as viruses jump between species at unprecedented rates. 

In our warming world, much of this process may unfortunately already be underway.  And efforts to reduce greenhouse gas emissions may not be enough to stop these events from unfolding. 

According to the study, climate change will become the biggest upstream risk factor for disease emergence, eclipsing deforestation, industrial agriculture, and the wildlife trade.  Pairing wildlife disease surveillance with real-time studies of environmental change may be part of the solution to predicting and preventing the next pandemic. 

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Climate change could spark the next pandemic, new study finds

Coronavirus and Climate Change

Photo, posted October 16, 2014, courtesy of Shawn Thomas / NPS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Atmosphere Is Thirstier | Earth Wise      

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The American West is in the throes of a two-decade-long drought.  The climate there is getting warmer and drier, which has led to increasing demand for water resources from both humans and ecosystems.  According to a new study by the Desert Research Institute and collaborators, the atmosphere across much of the U.S. is also demanding a greater share of water than it used to.

Evaporative demand, which is also called atmospheric thirst, is a measure of the potential loss of water from the earth’s surface up to the atmosphere.  It is a function of temperature, humidity, wind speed, and solar radiation.  The study, published in the Journal of Hydrometeorology, assessed trends in evaporative demand during a 40-year period from 1980-2020.

The study’s findings showed substantial increases in atmospheric thirst across much of the Western U.S. over that period, with the largest increases centered around the Rio Grande and Lower Colorado rivers.  This is important because atmospheric thirst is a persistent force in pushing Western landscapes and water supplies toward drought.

The study found that, on average, increases in temperature were responsible for 57% of the changes observed in atmospheric thirst, humidity 26%, and the other factors playing lesser roles.

For farmers and other water users, increases in atmospheric thirst mean that, in the future, more water will be required to meet existing water needs.  Crops already require more water than they did in the past and can be expected to require more water in the future.  Over time, for every drop of precipitation that falls, less and less water is likely to drain into streams, wetlands, aquifers, or other water bodies.

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New study shows robust increases in atmospheric thirst across much of U.S. during past 40 years

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Phasing Out Disposables | Earth Wise      

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Humans generate a remarkable amount of garbage.  According to the World Bank, humans produce 4.5 trillion pounds of trash every year, with at least 33% of this garbage not managed in an environmentally-safe manner. By 2050, global garbage generation is expected to reach nearly 7.5 trillion pounds a year. 

Globally, an average of 1.6 lbs of waste is generated per person per day.  While high-income countries only account for 16% of the global population, they are responsible for about 34% of the world’s waste. 

But almost everything humans throw away was bought from a company.   Whether it was the packaging or the product itself, we purchased it from somewhere.  There’s a growing movement to hold the companies responsible for the trash they produce. 

Faced with increasing consumer consciousness, many companies are stepping up and announcing initiatives to reduce their waste.  Starbucks is one of them.  The company’s white logo-emblazoned paper cups and clear plastic cups are instantly recognizable symbols of the brand.  But these ubiquitous cups are disposable and also serve as a symbol of our throwaway society. 

By the end of next year, Starbucks is planning to allow customers to use their own personal mugs at every location in the U.S. and Canada.  By 2025, the company wants every customer to be able to use either their own mug or to borrow a ceramic or reusable to-go mug.  This borrow-a-mug program is currently being tested in eight different markets around the globe. 

In lieu of regulation mandating corporate responsibility for waste, we will have to hope that more companies do the right thing.

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Starbucks is planning to phase out its iconic cups

Photo, posted June 11, 2010, courtesy of Sunghwan Yoon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Plight Of Monarch Butterflies | Earth Wise

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The monarch butterfly is one of the world’s best-known butterflies and has become the symbol for a whole class of imperiled pollinators.  Populations of the iconic orange-and-black insects have declined dramatically in recent decades. 

According to the U.S. Fish and Wildlife Service, the eastern monarch population has dropped 88% between 1996 and 2020.  Habitat loss, pesticide use, and global climate change are some of the factors driving monarch butterfly population declines. 

According to a new study led by scientists at Emory University, monarch butterflies are also increasingly plagued by a debilitating parasite.  The study, which was recently published in The Journal of Animal Ecology, reviewed 50 years of data on the infection rate of wild monarch butterflies by the protozoan Ophryocystis elektrosirrha (or O.E.).  The research team found that the O.E. infection rate had increased from less than 1% of the eastern monarch population in 1968 to as much as 10% today.

The O.E. parasite invades the gut of monarch caterpillars.  If the adult butterfly leaves the pupal stage with a severe parasitic infection, it begins oozing fluids from its body and dies. If the infection is lighter and the butterfly survives, it will not fly as well or live as long as uninfected butterflies.  

The study found that one of the contributors to the rise in parasitism is the increased density of monarchs in places where they lay their eggs.  The increased density may be due to several factors, including the loss of habitat, the widespread planting of non-native milkweed, and by people raising large numbers of monarchs in confined spaces. 

If the infection rate continues to increase, monarch butterfly populations will likely continue to plummet. 

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Monarch butterflies increasingly plagued by parasites

Plight of the Monarch

Saving The Monarch Butterfly

Photo, posted September 18, 2008, courtesy of Roy Niswanger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Humans And Microplastics | Earth Wise

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While plastic comes in all different shapes and sizes, those that are less than five millimeters in length are called microplastics.  Primary sources of microplastics include microfibers from clothing, microbeads, and plastic pellets (known as nurdles).  Secondary sources of microplastics come from larger plastic debris, like bottles and bags, that degrades into smaller bits over time. 

Microplastic pollution can be found everywhere on earth, from the top of the tallest mountains to the bottom of the deepest oceans.  Microplastics are in the food we eat, the water we drink, and the air we breathe. 

According to research recently published in the journal Exposure & Health, humans ingest an average of five grams of plastic particles per week. This is roughly equivalent to the weight of a credit card.  The plastic particles are trafficked in via food, such as seafood and salt in particular, as well as water.  In fact, those who rely on plastic bottled water for their drinking needs ingest an additional 1,700 plastic particles each week.   

Microplastics have also been detected in human blood for the first time.  According to new research recently published in the journal Environment International, scientists detected microplastics in nearly 80% of the people they tested. 

Half of the blood samples contained PET plastic, which is commonly used for drinking bottles.  One third of the blood samples contained polystyrene plastic, which is often used for food packaging.  One quarter of the blood samples contained polyethylene plastic, which is used to make things like shopping bags and detergent bottles. 

With plastic production predicted to double by 2040, more research is urgently needed to understand how ingesting microplastics affects human health.

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Health risk due to micro- and nanoplastics in food

Microplastics found in human blood for first time

Discovery and quantification of plastic particle pollution in human blood

Photo, posted November 3, 2012, courtesy of Laura via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Octopuses And Litter | Earth Wise

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Octopuses are remarkably intelligent animals.  They have a larger brain for their body size than all other animals apart from birds and mammals.  They exhibit high-order cognitive behaviors including tool use and problem solving.  Some captive octopuses learned to shoot jets of water at aquarium light switches to turn them off.  Others have learned to unscrew jar lids to get at food.

A recent analysis of underwater imaging has shown that octopuses are increasingly using discarded bottles, cans, and other human-generated litter as shelter or as a place to lay eggs.

The research documented 24 species of octopus sheltering inside glass bottles, cans, and even an old battery.  Some buried themselves under a mixture of bottle caps and seashells.  Others even carried plastic items around while walking on just two tentacles to disguise themselves from predators.

The octopuses showed a preference for unbroken items and for darker or opaque containers.  Normally, octopuses make use of natural shelters such as seashells.  Whether they are making use of litter simply because there is so much of it around or because there is an increasing lack of natural items is not clear.

As with all other aspects of the growing problem of litter in the oceans, this new trend is not a good one.  Sheltering or laying eggs inside discarded tires, batteries, or plastic items has the potential to expose octopuses to heavy metals and other harmful chemicals.

Octopuses are intelligent and resourceful animals, and they will use whatever they have at their disposal to continue sheltering or moving around with protection from potential predators.

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Octopuses Have Learned to Make Use of Ocean Litter, Study Finds

Photo, posted May 13, 2014, courtesy of Elias Levy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Florida’s Starving Manatees | Earth Wise

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Manatees, also called “sea cows”, have been the victims of farm runoff.  They have starved to death by the hundreds along Florida’s east coast because algae blooms fed by nitrogen-rich fertilizer runoff are proliferating on the ocean surface and blocking sunlight from reaching seagrass below.  Seagrass is the primary source of food for manatees in the winter.  As seagrass dies off, so do the manatees.

Over 1,000 manatees have been found dead so far this year.  It is estimated that fewer than 8,000 remain in Florida waters.  Efforts are underway to restore coastal seagrass in the region as well as clams and oysters, which filter pollutants from water.  Unless the water is cleared up, it will be difficult to regrow the seagrass.  But the current situation is that manatees are so short on food that they are eating seagrass roots, killing the plants and thwarting efforts to help seagrass recovery.

Given this dire situation, the federal governmental has approved a program of feeding manatees.  The starving animals will be fed by hand in Florida, which is a rare wildlife intervention.  Conservation agencies tend to favor leaving wild animals to their own foraging and hunting so that they don’t become dependent on human handouts.

During the trial phase of the program, wildlife experts are likely to feed the animals romaine lettuce and cabbage, which is what manatees in captivity eat.  The hope is to give the animals enough additional food for them to get through the winter.  The trial feeding will begin on private property.  It remains illegal for the public to feed manatees.

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Florida to feed starving manatees in rare conservation move

Photo, posted February 21, 2008, courtesy of Keith Ramos/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Crops | Earth Wise

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A new NASA study published in the journal Nature Food looks at the impact of global climate change on food crops.  According to the study, declines in global crop yields are likely to become apparent by 2030 if high greenhouse gas emissions continue.

The study used advanced climate and agriculture models to predict the effects of projected increases in temperature, shifts in rainfall patterns, and elevated surface carbon dioxide concentrations from human-caused greenhouse gas emissions.

These climate changes would make it more difficult to grow corn in the tropics but would actually expand wheat’s growing range.  The reduction in corn yields could be as much as 24% by late in the century.   Corn Is grown all over the world and large quantities are produced in countries nearer to the equator.  As temperatures rise in countries such as the US, Brazil, and China, yields are likely to decline because of the increased stress on the plants.

Wheat, which grows best in temperate climates may see a broader area where it can be grown as temperatures rise, but these gains are likely to level off by mid-century.

Rising temperature is not the only factor influencing crop yields.  Rising carbon dioxide levels have a positive effect on photosynthesis and therefore on crop yields, especially for wheat.  But changing rainfall patterns and rising temperatures can affect the length of growing seasons and accelerate crop maturity.  This can result in the production of less grain than in a longer development period.

The changing climate has complicated effects on the growth of breadbasket crops and will be felt worldwide.

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Web Links

Global Climate Change Impact on Crops Expected Within 10 Years, NASA Study Finds

Photo, posted September 8, 2004, courtesy of Lynn Ketchum/Oregon State University 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...)