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Reducing methane from cattle

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Livestock is responsible for almost 15% of global greenhouse gas emissions.  Most of that is in the form of methane that cattle release when they burp.  Grazing cattle produce more methane than feedlot cattle or dairy cows because they eat more fiber from grass.  There are 9 million dairy cows in the U.S. but more than 64 million beef cattle.

Beef cattle spend most of their lives grazing in pastures and producing methane.  Controlling the food of pasture-raised cattle is difficult because they often graze far from ranches for extended periods of time.  During the winter and during times when grass is scarce, ranchers supplement the diet of cattle.

A new study by researchers at the University of California – Davis has found that feeding grazing cattle a seaweed supplement in pellet form reduced their methane emissions by nearly 40% without affecting their health or weight.  There have been previous studies that showed seaweed cut methane emissions by 82% in feedlot cattle and over 50% in dairy cows.  But this is the first study to test the effects of seaweed on grazing beef cattle.

The seaweed pellets were made available to grazing cattle and they ate the supplement voluntarily.  Compared to a group of cattle who didn’t receive the supplements, the seaweed eaters had a 40% reduction in methane emissions.

Other research studies to reduce methane emissions using feed additives have taken place in controlled environments with daily supplements.  This method provides a way to make a seaweed supplement easily available to grazing animals.  It could even be introduced through a lick block for cattle.

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Feeding Grazing Cattle Seaweed Cuts Methane Emissions by Almost 40%

Photo, posted February 18, 2016, courtesy of Beverly Moseley/NRCS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Reducing farm nutrient pollution

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When farmers add nutrients to their fields in excess of their crops’ ability to utilize them, these excess nutrients can enter the surrounding environments and create environmental problems.  The primary culprits are nitrogen and phosphorous.  These fertilizer components emerge from fields and enter local waterways in surface runoff.

Researchers at the University of Illinois Urbana-Champaign have developed a form of designer biochar that can provide phosphorous in a time-released fashion and reduce the amount that escapes into the environment.

The researchers used sawdust and lime sludge, which are byproducts from milling and water treatment plants, respectively.  They mixed the two ingredients and formed pellets which were then slow-burned in low-oxygen conditions to create phosphorous-laden designer biochar.  Once the pellets bind all the phosphorous they can hold, they can be spread onto fields where the nutrient is slowly released over time.

They tested the pellets in working field conditions.  The pellets are used to remove phosphorous from drainage water and then can be reused in the field to provide the nutrient to the plants.   

The results were very encouraging.  The biochar proved to be a very effective way to provide phosphorous to crops and then reduce how much phosphorous enters the environment.  The cost of producing the biochar pellets was less than half that of alternative substances for phosphorous removal. 

There is currently no regulation that requires farmers to remove phosphorous from drainage water but there are a growing number of conservation-minded farmers who want to reduce nitrogen and phosphorous losses from their fields.  The idea that the recyclable pellets can both provide and control phosphorous is an attractive one.

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Scientists tackle farm nutrient pollution with sustainable, affordable designer biochar pellets

Photo, posted July 16, 2016, courtesy of Rick Obst via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Big Food and greenhouse gas emissions

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The global food system is responsible for as much as 40% of human-generated greenhouse gas emissions. The investor advocacy group Ceres has tracked whether the 50 largest North American food and agriculture companies have set targets to lower their emissions and whether doing so has actually resulted in lower emissions.

The emissions from food and agriculture companies are grouped into three so-called scopes.  Scope 1 are emissions from a company’s direct operations.  Scope 2 are emissions from its energy use.  Scope 3 are emissions from a company’s supply chain:  from the farmers who grow crops, raise cattle, and otherwise provide necessary items for a company’s final products.  In the food industry, the scope 3 category is responsible for about 90% of overall emissions.

Of the 50 food companies studied, 23 reduced their scope 1 and scope 2 emissions over the past 2 years, but only 12 reduced their scope 3 emissions.  Companies have more control over their scope 1 and scope 2 emissions. 

Reducing scope 3 emissions is more difficult.  And most companies haven’t set scope 3 reduction targets. 

The findings of the study suggest that reducing scope 3 emissions is especially difficult for companies whose supply chains are linked to carbon-intensive commodities, like meat, or crops linked to deforestation or land-use change, both of which result in increased emissions.

In March, the Securities and Exchange Commission finalized rules requiring companies to disclose their climate risk to regulators, increasing the visibility of the food industry emissions issue.

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North America’s Biggest Food Companies Are Struggling to Lower Their Greenhouse Gas Emissions

Photo, posted October 13, 2011, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hope for amphibians

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There are more than 7,000 known species of amphibians, the group of animals that includes frogs, toads, and salamanders.  Over the past 25 years, more than 90 species are believed to have gone extinct and at least 500 more have declining populations.

There are many factors contributing to the decline of amphibian populations but the most alarming is a fungus called Batrachochytrium dendrobatidis – or Bd – that ravages the skin of frogs and toads and eventually causes heart failure.  The fungus has been devastating amphibians on nearly every continent.

In a recent paper in the journal Current Biology, scientists at the University of California Riverside documented the discovery of a virus that infects Bd and could be engineered to control the fungal disease.

The researchers were studying the population genetics of the Bd fungus with DNA sequencing technology and uncovered the virus inside the fungal genome.  Some strains of the fungus are infected with the virus and others are not.  They are now looking for insights into the ways that the virus operates to see how it gets into the fungal cells.  The goal is to engineer the virus to infect more strains of the fungus and potentially end the global amphibian pandemic.

Frogs and toads control bad insects, crop pests, and mosquitos.  If their populations around the world collapse, it could be devastating.  They are already having difficulty coping with warmer temperatures, stronger UV light, and worsening water quality in many places. 

Some amphibian species are already acquiring resistance to Bd.  The UCR researchers are hoping to assist nature in taking its course.

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Discovery could end global amphibian pandemic

Photo, posted August 25, 2010, courtesy of Kev Chapman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The health impacts of gas venting and flaring

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Oil and gas producers around the world use venting and flaring to remove excess natural gas in crude oil production.  Flaring is the process of burning excess natural gas at the production well using a flare to ignite the methane and other components in the gas, while venting is the direct release of natural gas into the atmosphere. 

Both practices are major sources of greenhouse gas emissions contributing to global warming.   Venting and flaring release carbon dioxide and methane – two major greenhouse gases. 

The practices contribute to air pollution in surrounding and downwind communities, resulting in increased risk of hospitalizations, emergency room visits, worsening asthma, and even premature death.  In fact, according to a new study recently published in the journal GeoHealth, pollution from oil and gas venting and flaring results in $7.4 billion in health damages, more than 700 premature deaths, and 73,000 asthma exacerbations among children in the United States annually. 

The study, which was led by researchers at the University of North Carolina, Boston University, and the Environmental Defense Fund, also found that emissions are underreported, and controlling emissions would be profitable for operators and would significantly improve public health.

The research team found that Texas, Pennsylvania, and Colorado had the highest health burdens in this analysis, accounting for 45% of the premature deaths. 

The researchers hope their findings will help improve air quality and human health by reducing emissions from venting and flaring. 

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New study quantifies health impacts from oil and gas flaring in U.S. 

Photo, posted June 20, 2020, courtesy of Jonathan Cutrer 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

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

Skydiving Salamanders | Earth Wise

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The redwoods of the California coast are the tallest trees in the world.  They are typically a couple of hundred feet tall and the tallest rise to a height of as much as 380 feet.  Scientists have been studying the unique world of the redwood forest canopy for years.  There are multiple animals that actually live up there.  In fact, some spend their entire lives at the top of a single tree.

Over the past 20 years, researchers have been climbing redwoods to observe, capture, and mark salamanders that live in the canopy.  The most arboreal species, called the wandering salamander, is a four-inch-long creature what moves up and down the branches of a tree where it spends its entire life.  The researchers discovered a remarkable ability for the little amphibian.

The salamander readily leaps from perches in the crowns of redwood trees and has the ability to easily maneuver in midair back to a trunk or branch before it plummets to the ground.  When the salamanders were startled by climbing researchers, they simply leap from the canopy and find their way to another perch lower in the tree.

The salamanders assume a skydiving posture with their forelimbs splayed out and can steer themselves by pumping their tails up and down.  They can flip themselves over if they end up upside down.  They have an impressive level of control.

What is most remarkable is that the salamanders, apart from having slightly larger foot pads, look no different from other salamanders that aren’t skydivers.  They have no skin flaps or other anatomical adaptations that would give them the ability to glide.  The researchers hope to eventually figure out just how these creatures have become expert skydivers.

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Skydiving salamanders live in world’s tallest trees

Photo, posted August 5, 2010, courtesy of Benson Kua via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Smart Window | Earth Wise

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Researchers at Oxford University have developed a new adaptable smart window technology that has the potential of reducing the energy usage of the average home by a third.

The technology uses a spectrally tunable low-emissivity coating that can control the amount of heat that comes into a room without affecting the quality of the light that enters.

The thermal energy from the sun’s infrared rays is absorbed by the glass and then is re-emitted as heat.  That heat can either be used to warm the room using transparent electrical heaters embedded in the glass or can be reflected away to cool the room.  The windows can change according to seasonal needs.

The researchers built a prototype using a material called an active chalcogenide-based phase change material.  When it is cold, the infrared rays from the sunlight are harvested and used to heat the building.  When it is warm, the new glass can switch state to reflect the heat and reduce the need for air conditioning.  The active phase change material is adjustable so that the amount of heat absorbed or reflected can be tuned for precise temperature control.  There is essentially no effect on visible light passing through the window.  Current low-emissivity glass for windows can reduce heat transfer, but its properties cannot be altered according to seasonal needs.

The researchers estimate that using windows fitted with the new prototype glass – including the energy required to control the film – would save 20 to 34% in energy usage annually compared to double-glazed windows found in many modern homes.

A spinout company from Oxford called Bodle Technologies is collaborating with two existing industrial partners to develop the technology further.

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New adaptable smart window coating could help heat or cool a home and save energy

Photo, posted April 26, 2008, courtesy of Lima Andruska via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Cost Of Invasive Species | Earth Wise

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A new study published in Nature has tried for the first time to put a price tag on the impact of invasive species.  Researchers have been studying the effects of invasive species for decades, but it is a problem that has not really captured the attention of the public and policy makers.

According to the research by scientists at the French National Museum of Natural History, from 1970 to 2017, invasive species have cost the global economy at least $1.28 trillion dollars in damages and efforts to control them.

The team screened over 19,000 published papers, ultimately analyzing nearly 2,000 that detailed costs of various invasions at particular times.   Annual costs roughly doubled every six years, reaching a yearly bill of $162 billion in 2017.

The five costliest invasive species are Aedes mosquitos, rats, cats, termites, and fire ants, collectively accounting for a quarter of the global damage.

Asian tiger mosquitos and yellow fever mosquitos alone accounted for $149 billion in damage to public health as they spread from country to country.  Rats hitchhike on human boats and drive native species to extinction on islands around the world.  Cats inflict damage primarily by their impact on native biodiversity.  By some estimates, they kill a billion birds each year in the US alone.   Termites, as they spread across the globe, wreak havoc on all sorts of infrastructure.  Fire ants can feed on a variety of seedlings, from citrus to soybeans, reduce the size of grazing lands for livestock and bite and sting farm animals and humans.

The study shows invasive species are a massive problem that is getting worse.

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Invasive Species Cost Billions of Dollars in Damages Annually, Researchers Find

Photo, posted March 29, 2012, courtesy of Aleksey Gnilenkov via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The United States And Ticks | Earth Wise

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Tiny ticks are a big problem.  Measuring only three to five millimeters in size, ticks are widely distributed around the world.  They are external parasites, feasting on the blood of birds, reptiles, amphibians, and mammals – including humans.

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

But while the prevalence of tick-borne illnesses has steadily increased in the United States over the past two decades, a new study on tick surveillance and control “has revealed an inconsistent and often under-supported patchwork of programs across the country.”

The study, by university researchers at the CDC’s five Vector-Borne Disease Regional Centers of Excellence, is the first-ever examination of tick management programs in the United States.  The researchers found clear gaps in our public health infrastructure. 

According to the study, which was recently published in the Journal of Medical Entomology, less than 50% of public health and vector-control agencies conduct tick surveillance.  Only 25% test ticks for disease-causing germs.  And only 12% conduct or support tick-control efforts.  Researchers also discovered that the capacity for public tick-control efforts is low, as is the capacity for information and data sharing between agencies on ticks.    

The findings highlight the degree to which tick surveillance and control is lagging in the United States.  According to the research team, greater support for tick-management programs is critical, and they hope their findings will serve as a baseline from which to measure future improvements.  

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Tick surveillance and control lagging in US

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

Earth Wise is a production of WAMC Northeast Public Radio.

A Squid Skin Blanket

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Ultra-lightweight space blankets have been around for a long time.  Marathon runners wrap themselves in them to avoid losing body heat after a race.  They are very effective, but the amount of heat that they trap is fixed.  There is no way to regulate how much heat is trapped or released using a space blanket.

Researchers at the University of California, Irvine have developed a next-generation, adaptive space blanket that allows users to control their temperature.  The inspiration for the design was the skins of various species of squids, octopi and cuttlefish.  The ability of these aquatic creatures to camouflage themselves by rapidly changing color is due, in part, to skin cells called chromatophores that can instantly change from tiny points to flattened disks.

The Irvine researchers have developed a material that contains a layer of tiny metal islands that border each other.  In the relaxed state, the islands are bunched together, and the material reflects and traps heat, much like a conventional Mylar space blanket.  But when the material is stretched, the islands spread apart, which allows infrared radiation to go through and heat to escape.

The researchers envision many other applications for the novel material, including adaptable insulation for buildings and tents that can be adapted to different weather conditions.  There is even the possibility of clothing that can be adjusted to suit the comfort of each person.

The new material is lightweight, easy and inexpensive to manufacture, and is durable.  It can be stretched and returned to its original state thousands of times.  Some day we might all be wrapping ourselves in imitation squid skins.

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Squid skin inspires creation of next-generation space blanket

Photo, posted May 29, 2005, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Smog And Solar Power

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China has been struggling with some of the worst air pollution in the world.  Beijing frequently sits under a brown blanket made of exhaust gases from industry, cars and coal fires, which dump harmful particulate matter, soot, sulfur dioxide and nitrogen oxides into the air.

The human health consequences are severe.   According to the World Health Organization,air pollution contributes to about 1.6 million premature deaths in China each year.  World-wide, air pollution is implicated in over 7 million deaths annually.

Faced with this air pollution crisis, China has undertaken a wide variety of measures to improve its air and curb carbon dioxide emissions alongthe way.  Among other things, China has invested heavily in the deployment of solar power and has plans for ever greater expansion of solar power in the future.

A study by researchers at ETH in Zurich looked at the impact of China’s air pollution on the production of solar energy.  The smog in China’s cities reduces the amount of solar radiation that reaches the ground and therefore significantly reduces the power output of solar energy systems. According to the study, solar radiation would increase by an average of 11% nationwide as a result of strict air pollution control measures.  In some places, cleaning up the air would result in 26% more energy production.

China’s electric power industry is the world’s largest electricity producer, having passed the United States in 2011.  Two-thirds of the electricity in China still comes from coal, which, apart from the serious climate and health consequences associated with its use, continues to make it more difficult to switch to clean solar power.  Much work remains to be done.

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Fighting smog supports solar power

Photo, posted February 7, 2014, courtesy of Flickr. 

Earth Wise is a production of WAMC Northeast Public Radio.

Labeling Genetically Engineered Foods

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There has been a great deal of debate over mandating labels for genetically engineered foods.  On the pro side, people argue that they have a right to know whether what they are eating contains GMO – or as they are also called GE — ingredients.  On the con side, people argue that the aversion toward GE is unfounded and that labeling foods will simply drive away consumers undeservedly.

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