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Fighting Malaria With Gene-Drive Technology | Earth Wise

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Malaria continues to be a major health hazard throughout the tropical and subtropical regions of the world. There were 228 million cases of malaria in 2018 and over 400,000 deaths. 

Malaria is a mosquito-borne infectious disease spread by 40 of the world’s 3,500 mosquito species.  So, efforts to control mosquito populations are the primary strategy to eradicate malaria.

A team led by Imperial College London has created a genetic modification that distorts the sex ratio of a population of Anopheles gambiae mosquitoes using “gene drive” technology.  The modification works by using a DNA-cutting enzyme to destroy the X chromosome during the production of sperm, which leads to predominantly male offspring, since females require two X chromosomes.  The modification is coupled to a gene drive to allow it to spread through a population in a very effective way.  A gene drive is a genetic engineering technology that propagates a particular modification by assuring that a specific form of a gene (or allele) will be transmitted with far more than the natural 50% probability.

The result of this is that mosquitoes produce more male offspring, eventually leading to no females being born and a total collapse in the population. The mosquitoes studied are the main malaria vector in sub-Saharan Africa.  The hope is that mosquitoes carrying a sex-distorter gene drive would be released in the future, spreading the male bias with local malaria-carrying populations and causing them to collapse.  Only female mosquitoes bite and take blood meals.  If the gene drive technology works in the field, it could be a game-changer in the fight to eliminate malaria.

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Malaria mosquitoes eliminated in lab by creating all-male populations

Photo, posted June 20, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Concrete Production And Diminishing Coal Burning | Earth Wise

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Coal burning is still one of the primary means of generating electricity in the United States, but its use is diminishing and doing so fairly rapidly.  The coal burning process produces residual, incombustible materials.  One of them is fly ash, which is composed of fine, glassy, rounded particles rich in silicon, aluminum, calcium, and iron oxides.  Fly ash is captured from coal plant flue gas by precipitators and bag filters. It turns out that two-thirds of this fly ash is not dumped into landfills or impoundments, but rather is put to use.

Because of its chemical and physical characteristics, fly ash can substitute for a portion of portland cement in concrete.  Using this byproduct material in making cement actually reduces its cost. Beyond cost, the addition of fly ash as a so-called supplementary cementitious material or SCM improves concrete’s long-term strength and reduces porosity and permeability.  It reduces the risk of thermal cracking and provides good long-term mechanical properties.

The amount of fly ash used in concrete products increased by 5% between 2011 and 2017 while the amount produced dropped by 36%.  Concrete production continues to increase steadily while fly ash production is steadily dropping.

Therefore, the concrete industry is looking for alternative sources of SCM.  The most obvious is the approximately 1/3 of fly ash that hasn’t been used to make concrete.  Much of that is landfilled or ponded onsite at power plants.  So, opportunities exist for excavating or dredging and recovering these materials.

As coal burning goes away, concrete manufacturing needs to make some changes.

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What Does the Changing Face of Electricity Production Mean for Concrete?

Photo, posted February 16, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

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Many of us are aware of the infamous ocean “garbage patches” of floating plastic.  The Great Pacific Garbage Patch is roughly the size of Texas.  But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total.  The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around.  One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor.  This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets. 

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents.  These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity.  Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom.  As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewable Energy And The Post-COVID World | Earth Wise

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As is the case for virtually all sectors of the global economy, the short-term prospects for wind and solar power look pretty grim.  Lockdowns, social distancing requirements, and financial upheavals have put many new projects on ice and have halted production at factories making solar panels and wind turbines.  Sales of home solar have struggled as people have put off spending during the economic slowdown.

Ironically, the shutdowns aimed at reducing the spread of the Coronavirus have led to renewable sources accounting for an increased share of power generation.  Global energy demand has plummeted and, because of the low cost of solar and wind power, sources like coal and nuclear power have been curtailed in favor of the renewables.  The dramatically reduced demand has pushed oil and gas prices to historic lows and has left fossil fuel companies struggling to find storage space for the glut of product.

When the world emerges from the pandemic, the question is whether renewable energy will end up on a faster track than before or will end up in a long-term slowdown.  The answer will depend to large extent on the choices political leaders make.

Leaders will unquestionably be designing economic recovery packages.  Such packages could accelerate the shift towards wind and solar power, or they could prop up the fossil fuel economy.  Unfortunately, leaders are prone to be motivated by lobbyists more than by the greater needs of society.  The global economic upheaval represents a real opportunity to change the pace of efforts to address climate change.  Whether that change is a positive one or a negative one is just another looming question facing society when we emerge from the pandemic.

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How Renewable Energy Could Emerge on Top After the Pandemic

Photo, posted April 12, 2020, courtesy of Jeremy Segrott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Planting Trees and Climate Change | Earth Wise

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Forests are among the most important natural carbon sinks.  Trees remove carbon from the air and store it in their trunks, branches, and leaves, and transfer part of it into the soil.  But in some regions, these natural carbon sinks are starting to weaken due to deforestation, forest degradation, and the impacts of climate change.  This problem has led some climate mitigation projects to focus on increasing the overall number of trees on the planet. 

But, according to a paper recently published in the journal Science, “we can’t plant our way out of climate change.”  That’s the simple message from Restoration Ecologist Karen Holl and University of São Paulo Professor Pedro Brancalion to anyone who thinks planting one trillion trees will reverse the effects of climate change.  They say planting more trees is only one piece of the puzzle.  Any initiatives like 1t.org or the Trillion Tree Campaign must be done carefully and be accompanied by commitments to long-term management.

Tree plantings can provide many environmental benefits, including improving water quality, biodiversity, and increasing shade.  But trees can sometimes have undesirable impacts, such as harming native species and ecosystems or reducing water availability, depending on where and how the trees are planted.

The authors suggest four principles that should guide forest enhancement initiatives: reduce forest clearing and degradation, balance ecological and social goals, view tree plantings as one part of a multifaceted solution, and plan, coordinate and monitor the work. 

While tree plantings can clearly be part of the solution, slowing the pace of climate change requires a comprehensive approach that must start with burning less fossil fuels.

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Challenges in tree-planting programs

Planting trees is no panacea for climate change

Photo, posted December 1, 2019, courtesy of Akuppa John Wigham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Environmental Injustice And the Coronavirus | Earth Wise

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Cities and towns across the United States continue to wrestle with the devastating impacts of the COVID-19 pandemic and none have been hit harder than low-income and minority communities.  Places like Detroit, Chicago, and St. James Parish in Louisiana have suffered from decades of economic inequality and pollution in their poorest neighborhoods and many of these same places have experienced some of the highest mortality rates from the virus.

Recent studies have shown a link between high levels of pollution and the risk of death from COVID-19.  Pollution of various kinds are higher in low-income communities and communities of color.  Such communities don’t have a strong political voice so that laws and environmental regulations are not enforced like there are in white, higher-income communities.  Thus, these communities have highways, landfills, factories, chemical facilities, paper mills, and other pollution sources that communities with economic power – and therefore political power – manage to avoid.

People living in low-income communities and communities of color tend to have higher rates of underlying health conditions like diabetes, heart disease, and asthma.  They have less healthy diets – more fast food and fewer grocery stores.  Part of the reason these communities have a higher risk of mortality from COVID-19 infection is that many people have reduced lung capacity as a result of exposure to pollutants.

The Trump administration has been suspending enforcement of environmental regulations during the pandemic.  Communities already affected by environmental injustice will bear the brunt of this decision.  Groups like nursing home populations, meat packers, prisoners and the poor are suddenly highly visible.  COVID-19 is exposing the real differences between the Haves and the Have-Nots in this country.

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Connecting the Dots Between Environmental Injustice and the Coronavirus

Photo, posted May 2, 2006, courtesy of Sean Benham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recovering Marine Life By 2050 | Earth Wise

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Marine life has faced challenges for a long time.   There have been centuries of overfishing in many places and pollution of various types has been especially harmful in recent decades.   But despite all of this, a new scientific review published in the journal Nature contends that marine life in the world’s oceans could be fully restored in as little as 30 years provided that aggressive conservation policies are adopted.

The research spotlights the strong resiliency of ocean animals and cites the successful recovery of a number of marine species, including humpback whales.

The study indicates that nations around the world must agree to designate 20 to 30 percent of the oceans as marine protected areas, institute sustainable fishing guidelines, and regulate pollution.  These measures would not come cheaply.  The estimated cost would be around $20 billion a year. 

However, the report also estimates that the economic return on this investment would be tenfold and would create millions of new jobs.  Rebuilding fish stocks and maintaining sustainable fishing policies could increase global profits of the seafood industry by over $50 billion a year.  Conserving coastal wetlands could save the insurance industry more than $50 billion a year as well by reducing storm damage.

A major sticking point, however, is climate change.  Climate change is increasing ocean temperatures and driving acidification.  Unless these changes are brought under control, the restoration of marine life is not going to be successful.  We have reached the point where it is within our power to choose between a future with a resilient and vibrant ocean or an irreversibly disrupted ocean.  Whether we embrace that challenge remains to be seen.

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Marine Life Could Recover By 2050 With the Right Policies, Study Finds

Photo, posted April 20, 2012, courtesy of Matthias Hiltner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Fresh Produce | Earth Wise

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Fresh fruits and vegetables can sometimes become contaminated by microorganisms during their long journey from fields to restaurants and grocery stores.  Contaminated produce can spoil other produce, which increases the number of fruits and vegetables in the supply chain that can cause illnesses. 

In order to prevent this cross-contamination between produce, researchers from Texas A&M University have designed a coating that can be applied to food-contact surfaces, like buckets, rollers, and conveyor belts.  The newly-created dual-function coating is both water-repellent and germicidal.  In other words, it can both repel and kill.  Without water, the researchers say bacteria can’t stick or multiply on surfaces, drastically reducing contamination.

To make this dual-function coating, the researchers chemically-attached a thin layer of silica to an aluminum sheet.  They then added a mixture of silica and lysozyme, a naturally-occurring germicidal protein found in egg whites and tears.  Together, the silica-aluminum and the silica-lysozyme formed microscopic bumps and crevices.  According to the research team, this rough texture, albeit microscopic, is the key to the coating’s superhydrophobic properties.  

The researchers tested the coating’s effectiveness at curbing the growth of two strains of disease-causing bacteria:  Salmonella and Listeria.  Upon review, the number of bacteria found on the dual-coating surfaces was 99.99% less than what was found on the uncoated surfaces. 

Despite the success in preventing bacterial spread, the research team said more research needs to be done to see how well the coating works for mitigating viral cross-contamination.  Since the coating would need to be reapplied after a certain amount of use, the researchers also plan to develop more permanent, dual-function coatings. 

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New dual-action coating keeps bacteria from cross-contaminating fresh produce

Photo, posted April 14, 2012, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Danger Of Relying On Future Technology | Earth Wise

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The need to mitigate the effects of climate change has been a global focus for about 40 years and has seen ever-changing views on what actions are needed.  The historical record has been defined by over-reliance on promises of new technology to solve climate change.  Looking to future technology to save the environment has been an excuse to postpone necessary action and avoid inconvenient changes in how we do things.

A study at Lancaster University in the UK published in Nature Climate Change exposes how such promises have raised expectations of more effective policy options becoming available in the future and have enabled the continued politics of inadequate action and skirting around the truth.

Even after four decades, rather than acting forcefully to reduce emissions, we are hoping that nuclear fusion power, giant carbon sucking machines, ice-restoration using vast numbers of wind-powered pumps, and spraying particulates into the atmosphere can address the climate crisis rather than dramatic changes in fossil fuel use.

The researchers mapped the history of climate targets in five phases.  Early on, the focus was on improved energy efficiency, large-scale enhancement of carbon sinks, and nuclear power.  Next, the focus was on cutting emissions with efficiency, fuel switching, and carbon capture and storage.  After that, bioenergy was the major focus.  Then, global carbon budgeting and potential negative emission technologies.  Currently, the focus is on temperature outcomes rather than emission targets.

Each novel promise competes with existing ideas and downplays any sense of urgency.   The researchers conclude that putting our hopes on yet more new technologies is unwise.  The time to act is now.

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Why relying on new technology won’t save the planet

Photo, posted February 13, 2019, courtesy of Jonathan Cutrer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Moving Up And Away | Earth Wise

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A new study by the Wildlife Conservation Society, the US Forest Service, and UC Berkeley has shown that mountain-dwelling species trying to escape warming temperatures may also be finding refuge from human pressure.

The study shows that nearly 60% of the world’s mountainous areas are under intense human pressure.  Most of that pressure occurs at lower elevations and mountain bases, where more people live, grow food, and build roads.  The researchers used climate models to predict how various species would move as the climate changes.   Based upon these predictions, they found that species tend to move to higher elevations, where temperatures are lower.  But those elevations also have more intact land for species because there is less human activity.

Mountains are home to over 85% of the world’s amphibians, birds, and mammals and these species are at risk from human activities such as agriculture, livestock grazing, and development.  These things reduce their habitats, but meanwhile the warming climate pushes them upslope as they struggle to find tolerable temperatures.

The researchers point to their study as new guidance for conservation efforts.  They warn that many conservation efforts don’t take into account the effects of human pressure.   Factoring in human pressure reveals the true extent of mountainous areas for species that are restricted to intact landscapes.  These are often the species that are of greatest concern to conservationists.  This true shape refers to how much land area is potentially available as habitat for a species as it moves up in elevation.  

The results offer a glimmer of hope for mountain-based species under climate change as they move away from the most intense human activity.

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Climate change may push some species to higher elevations — and out of harm’s way

Photo, posted November 22, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Methane-Eating Bacteria And Greenhouse Gas Emissions | Earth Wise

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One of the great concerns about the warming Arctic temperatures is that thawing permafrost will release alarming amounts of methane into the atmosphere.  Organic material in the permafrost begins to decompose when temperatures rise, and methane is released in the process.

Methane is a far more potent greenhouse gas than carbon dioxide.  Methane’s lifetime in the atmosphere is much shorter than carbon dioxide, but it is more efficient at trapping radiation.  Pound for pound, the comparative impact of methane is more than 25 times greater than carbon dioxide.

A new study, published by scientists at Purdue University, has discovered a type of methane-oxidizing bacteria living in upland Arctic soils that could potentially be reducing the amount of methane emitted by decomposing permafrost.

The findings of the research indicate that the net greenhouse gas emissions from the Arctic may be much smaller than previously modeled because of the increased productivity of a type of bacteria known as high affinity methanotrophs, or HAMs.  This group of bacteria uses atmospheric methane as an energy source.  The emissions from wetlands will potentially be very large, but the contribution from the uplands will be mitigated by the bacteria.

Organic-rich soils, including permafrost, comprise only 13% of the Arctic land area and are the major source of methane emissions.  The other 87% of the region is dominated by mineral-rich soils that support HAMs.  Because of this, overall methane emissions continue to be less than climate models have predicted.

While this is good news, the researchers warn that Arctic emissions overall will continue to increase as shown in other studies.

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Methane-Eating Bacteria Could Help Decrease Greenhouse Gas Emissions From Thawing Arctic Tundra

Photo, posted July 12, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Victory For Clean Water | Earth Wise

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Many of the nation’s environmental laws are under siege from the current administration, but a recent decision by the U.S. Supreme Court has solidified the Clean Water Act’s place as one of the country’s most effective environmental laws.

The case in question was about whether a wastewater treatment plant in Maui has been violating the Clean Water Act by polluting the ocean indirectly through groundwater.  Since the 1980s, the Lahaina wastewater treatment facility has been discharging millions of gallons of treated sewage each day into groundwater that reaches the waters off of Kahekili Beach, which is a popular snorkeling spot.   Groundwater, like any water beneath the land’s surface, can flow into major waterways such as rivers, streams, and, in this case, the ocean. 

In 2012, the nonprofit Earthjustice sued Maui county on behalf of four Maui community groups. Over the years, the Hawaii district court and the 9th Circuit appeals court ruled in favor of Earthjustice.  Last year, Maui County successfully petitioned the U.S. Supreme court to hear the case, which could have endangered the Clean Water Act.

On April 23, by a 6-3 vote, the court ruled that point source discharges to navigable waters through groundwater are regulated by the Clean Water Act when the addition of pollutants through groundwater is the functional equivalent of a direct discharge into navigable waters.

With this ruling, the Court rejected the Trump administration’s polluter-friendly position in the clearest of terms.  According to the opinion, written by Justice Breyer, the Court could not see how Congress could have intended to create such a large and obvious loophole in one of the key innovations of the Clean Water Act.  This is a victory for clean water.

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The Clean Water Case of the Century

Photo, posted June 30, 2018, courtesy of Kirt Edblom via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Small-Scale Climate Solutions | Earth Wise

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In order to meet international climate targets, we need to cut greenhouse gas emissions in half over the next decade and reach net-zero by mid-century.  Achieving this will require unprecedented and rapid changes in how energy is supplied, distributed and used.

Researchers at several European universities collected data on a wide variety of energy technologies at different scales and tested how well they performed in accomplishing an accelerated low-carbon transformation. 

Large-scale, costly, non-divisible or so-called lumpy technologies, such as utility-scale generation, nuclear power, carbon capture and storage, high-speed transportation, and whole-building retrofits are often seen as the most effective way to achieve emission-reduction goals. A key finding of their study is that low-carbon technologies that are smaller scale and can be mass deployed are more likely to enable a faster transition to net-zero emissions.

So-called granular options include solar panels, electricity storage batteries, heat pumps, smart thermostats, electric bikes, and ride-share services.  These options scale not by becoming larger but by replicating.

Small-scale options are quicker to deploy, their technologies have shorter lifespans and are less complex, so innovations and improvements can be brought to market more rapidly.  They are also more widely accessible and help create more jobs, giving governments a sound basis for strengthening climate policies.

However, smaller-scale technologies are not a panacea.  There are no small-scale replacements for industrial plants and other kinds of major infrastructure, but in many different contexts, they can outperform larger-scale alternatives as a means of accelerating the low-carbon transformation.

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Smaller scale solutions needed for rapid progress towards emissions targets

Photo, posted April 8, 2019, courtesy of the City of St Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Earth Itself Is Quieter | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

With about a third of the world’s population sheltering in place, our planet is much quieter these days.  It isn’t just our machines, vehicles, and factories that are making less noise.  The earth itself is quieter.  There has been a reduction in the earth’s seismic vibrations.

According to the journal Nature, various human-powered movements contribute to the persistent vibration of the earth’s crust.  Things like engines firing up in factories, trains pulling into stations, and trucks barreling down highways all make contributions to seismic activity.  Taken individually, such things are insignificant, but taken together, they produce a background of seismic noise that makes it difficult for seismologists to detect natural signals such as volcanic activity and earthquake aftershocks.

With much human activity on pause during the coronavirus outbreak, seismologists across the globe are seeing significant reductions in background seismic noise levels.

This respite in seismic noise, for as long as it lasts, represents an opportunity for scientists to better study the natural activity in the earth’s crust. Researchers studying the impact of ocean waves to predict volcanic activity and those who triangulate the location of earthquake epicenters may be able to make more sensitive measurements than under normal conditions.

There are very few positive things one can say about the coronavirus crisis, but it is providing opportunities to study and observe aspects of the natural world that are ordinarily drowned out by the bustle of humanity.

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Coronavirus lockdowns across the globe are actually causing the Earth to move less

Photo, posted March 9, 2020, courtesy of Jeremy Segrottvia Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildlife Reclaims Yosemite National Park | Earth Wise

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Our stories often discuss how human activities change the natural environment.  With most of us confined to our homes, the lack of human activities is having profound effects on the environment.  We are talking about some of these this week.

Yosemite National park is normally awash in humanity – there were over 300,000 visitors in April of 2019 and typically 4 million people visit each year.  But as of March 20, the park was closed to tourists to prevent the spread of the coronavirus.  Only a skeleton crew of employees remains in the park.

Without all the people, wildlife is coming out of hiding.  It did so in previous park closures during government shutdowns, but those closures were pretty short.  This one is expected to be the longest on record.

The bear population within the park has quadrupled and many larger animals – such as bobcats and coyotes – are congregating outside of cabins and other buildings and prowling empty roads and walkways instead of hanging back at the edges of human settlements. 

In addition, the air at Yosemite is cleaner due to the lack of exhaust and diesel, and Yosemite Valley is nearly silent, apart from natural sounds from the river and the wind.  According to some observers, the park’s current condition is probably similar to what visitors in the 19th century witnessed. 

The few park employees sheltering in place are taking advantage of the virtually unimpeded natural amenities of the park.  Many are hiking to its lakes and waterfalls, enjoying trails that are empty apart from animals.  As some of the people staying in the park have noted, one could not ask for a better place to be isolated.

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Coyotes, bobcats and bears: Wildlife is reclaiming Yosemite National Park

Photo, posted October 30, 2019, courtesy of Ania Mendrek via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Too Many Bison | Earth Wise

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The population of large herbivores in Yellowstone National Park has undergone many dramatic changes over the course of time.  The numbers of both the iconic Rocky Mountain elk and bison have gone up and down as a result of human interactions.

Bison, of course, once were a dominant species from east of the Appalachians to west of the Rocky Mountains, with most of an estimated 30 million living on the Great Plains.  As the west was settled, bison populations plummeted and by the late 1800s, they were nearly extinct.

When Yellowstone was established, there were exactly 22 bison in the park.  By 1925, there were more than 750 in the park and culling of the herd in the park’s Lamar Valley was practiced for the next four decades.

The elimination of predators like grey wolves and cougars in the early 1900s caused both elk and bison populations to mushroom and both underwent culling.  When culling was ended in 1968, there were 4,000 elk and 100 bison.  Within 20 years, those numbers were 20,000 and 1,000.   Reintroducing wolves and cougars reduced the elk population to about 5,000, but bison numbers have continued to grow, now reaching about 4,000.

While the long-term recovery of the Yellowstone bison herd is a major conservation success story, the fact is that bison are powerful ecosystem engineers.  Large numbers of them disrupt species distribution across scrub steppe and grasslands because of what they eat, trample, and rub their horns and bodies on.  They have a tremendous capacity to limit the structure and composition of ecosystems.

Park administrators have complicated management decisions to make to take into account the often wide range of ecological effects that abundant large herbivores can have on ecosystems.

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Bison in northern Yellowstone proving to be too much of a good thing

Photo, posted August 10, 2016, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plants Paying For Biofuels | Earth Wise

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Biofuels are an important element in broader strategies to replace petroleum in transportation fuels like gasoline, diesel, and jet fuel.  The idea is that biofuels recycle carbon by getting it from growing plants rather than from fossil sources.  The biggest problem with biofuels is that they cost more than conventional petroleum fuels, so there is economic incentive to keep burning the fossil fuels.

One strategy to make biofuels cost competitive is to have the plants provide additional economic benefits beyond being a feedstock for fuel.  This in principle can be done by engineering plants to produce valuable chemical compounds, or bioproducts, as they grow.  Bioproducts include such things as flavoring agents and fragrances as well as biodegradable plastic.  These bioproducts can be extracted from the plants and then the remaining plant material can be converted to fuel. 

Researchers at Lawrence Berkeley National Laboratory recently published a study to determine what quantities of bioproducts plants need to produce to result in cost-effective biofuel production.

The study looked at a compound called limonene, which is used for flavoring and fragrance.  They calculated that if this compound was accumulated at 0.6% of the biomass dry weight, it would offer net economic benefits to biorefineries.  This corresponds to recovering 130 pounds of limonene from 10 tons of sorghum on an acre of land.

Such quantities are completely practical but, on the other hand, none of these substances are needed in huge quantities. Just six refineries could supply the world with limonene.  So, fuel crops would need to be engineered to produce a broad range of bioproducts to enable a viable cost-effective biofuel industry.

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Making Biofuels Cheaper by Putting Plants to Work

Photo, posted September 28, 2019, courtesy of Michele Dorsey Walfred via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conservation In Vermont | Earth Wise

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In recent times, Vermont and neighboring states have been losing forest land to development at a rate of almost 1,500 acres per year.  With forest fragmentation gaining ground across New England, conserving land for future generations of people, wildlife, and plants has become both increasingly important and increasingly difficult.

According to a new study published by researchers at the University of Vermont, the state has already protected a third of the highest priority targeted lands needed to protect and connect valuable wildlife habitats and corridors.  The protected lands amount to 1.3 million acres.

Most of the currently conserved lands are forested.  However, there are high-priority targeted surface water and riparian areas – ponds, rivers, shorelines, and wetlands – and not nearly enough of these have been protected.  (Many animals require zones along waterways in which to travel between the habitats they need to survive).

The state of Vermont and a number of partners have laid out a comprehensive and thoughtful vision that would ensure that Vermont remains a good place for all forms of life in the future.  The new study provides a crucial benchmark of current levels of forest protection to help prioritize future conservation actions. 

Three groups dominate in responsibility for the state’s protected lands:  the federal government, the state government, and private non-profit organizations.  (Each of these account for roughly a third of existing protected lands).

Going forward, Vermont’s nonprofits will play an increasingly important role in land conservation, especially in continuing to protect those areas that are rich with species diversity.  Nonprofits are engaging more and more deeply in restoring wetlands that were previously degraded, planting new forests along river shores, and protecting unique natural communities while also protecting working forests and farmland.

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Vermont Has Conserved One Third of the Land Needed for an Ecologically Functional Future

Photo, posted June 15, 2014, courtesy of Wesley Carr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Safer Ways To Be Blue | Earth Wise

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Creating blue fabric has always been desirable for people.  It has never been easy, but the original way to do it – by using indigo from plants – has been around for 6,000 years.  Natural indigo is a rare commodity, often referred to as blue gold.  In the 19th century, synthetic indigo was developed and ultimately replaced the natural substance.

Synthetic indigo dye is not an environmentally friendly substance.  In order to get it to adhere to fabrics, substances called mordants are required.  These are commonly made from metals like chromium and aluminum, are generally toxic, and kill off plants exposed to factory wastewater, destroy ecosystems, and poison drinking water.   The dye itself is slow to decompose and is bad for the environment. 

Recently, an organic chemist in Brazil named Erick Bastos has figured out a new way to produce blue dye using, of all things, a pigment from beets.  By extracting the pigment and tweaking its molecular pattern, he has managed to transform the red color of the pigment to a brilliant blue.

Beet roots contain pigments called betalains and just a tiny amount of beetroot juice can render a lot of dye.  By mixing these pigments with a couple of ingredients, a chemical reaction occurred, and the color transformed from red, to yellow, then green, and finally blue.

Testing so far on human liver cells, retinal cells, and developing zebrafish has revealed no toxicity.  The results suggest that the new dye – dubbed BeetBlue – is safe.  Further testing is needed to know if it is truly safe and whether it will last in the wash.  Meanwhile, Professor Bastos is not patenting the dye and hopes it will provide a better way to be blue.

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How Do You Make a Less Toxic Blue Dye? Start With Red Beets

Photo, posted November 7, 2005, courtesy of Lain Buchanan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Giant Marine Preserve | Earth Wise

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The Seychelles islands are located east of Kenya, near the equator.  Its beautiful beaches, virgin jungles, thriving coral reefs, and UNESCO-listed nature reserves are among the many attractions of the archipelago’s 115 islands.  The larger inner islands are quite developed for tourists, studded with many luxurious five-star resorts.  The natural wonders of the Seychelles are clearly its prime asset.

Given this, the Seychelles have now established 154,000 square miles of marine protected areas, fulfilling a pledge to protect nearly a third of its vast territorial waters.  This is an area twice the size of Great Britain.

About half of the newly protected areas will be “no-take zones” in which economic activity such as fishing and mining will be prohibited.  Only limited economic activities will be permitted in the other half of the protected areas.

The President of the Seychelles signed the decree establishing the marine reserve in mid-March.  The reserve will help protect the nation’s fisheries resources and safeguard a host of species including endangered sea turtles, sharks, and the Indian Ocean’s last remaining population of dugongs, which are marine mammals similar to manatees.

The funding for managing and protecting the new marine reserves will come from what is termed a debt-for-nature deal.  It is an agreement that was worked out with the help of The Nature Conservancy that allows the country to restructure nearly $22 million in foreign debt in exchange for protecting marine resources and enacting climate adaptation measures.

This major expansion of the Seychelles’ marine protected area is a major step in the conservation of the archipelago’s biodiversity.  The success of that conservation will ultimately depend upon enforcement, public-private partnerships, and innovative management.

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Seychelles Creates a Marine Reserve Twice the Size of Great Britain

Photo, posted October 22, 2017, courtesy of Falco Ermet 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...)