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Assisted Colonization | Earth Wise

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As the pace of climate change continues to quicken, many species seem to be unable to keep up and could face extinction as a result.   There is a potential strategy for people to help species reach places with more suitable physical and biological conditions.  People could carry endangered animals to habitats cut off by mountains, rivers, or human-made barriers.  They could plant endangered trees higher up mountain slopes or to locations further north.  Such actions have been termed assisted colonization.

People have been moving species around the world throughout human history for various reasons either intentionally or inadvertently.  But as a conservation strategy, assisted colonization is quite controversial.

The argument is whether the risk of moving species to more favorable conditions outweighs the risk of inaction.  The salvation of one species could mean the destruction of another.   A species that seems perfectly innocuous when moved to one place can become a rampant invader in another.

An upcoming international conference on Biological Diversity to be held this fall in China may take up the issue of creating a set of guidelines on assisted colonization.   Such guidelines would help people assess which species to focus on; where, when, and how to move them; how to weigh the risks of action and inaction; and how to conduct such actions across international borders.  Assisted colonization may be useful in some instances and not in others.  There needs to be a way for the world to decide whether it is warranted or not.  With climate change posing a growing threat to many of the world’s species, this is an issue that should be addressed.

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Amid Climate Pressures, a Call for a Plan to Move Endangered Species

Photo, posted July 16, 2014, courtesy of Mark Spangler via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Carbon Dioxide Levels | Earth Wise

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The coronavirus pandemic caused a temporary dip in the burning of fossil fuels around the world as many human activities were diminished or curtailed entirely.  Despite this, the amount of carbon dioxide in the atmosphere set a record in May, reaching the highest levels in human history.

Scientific instruments atop the Mauna Loa volcano in Hawaii measured an average of 419 parts per million for the month, according to analysis from both the Scripps Institution of Oceanography and the National Oceanic and Atmospheric Administration.

This level is about half a percent more than the previous record of 417 ppm, set in May of 2020.  Carbon dioxide is the largest greenhouse gas contributor driving global warming and, according to scientists, there hasn’t been this much of it in the atmosphere for millions of years.

Global emissions of carbon dioxide were actually 5.8 percent lower in 2020 than 2019, as a result of pandemic lockdowns.  This was the largest one-year drop ever recorded.  But humanity was still responsible for emitting more than 31 billion tons of carbon dioxide last year.  About half of that CO2 is absorbed by the world’s trees and oceans, but the other half lingers in the atmosphere for thousands of years, gradually warming the planet via the greenhouse effect.

As long as we keep emitting carbon dioxide, it is going to continue to pile up in the atmosphere.  The only way to stop it is for the world’s nations to zero out their net emissions, mostly by switching away from fossil fuels to technologies that do not emit carbon dioxide, such as electric vehicles fueled by wind, solar, or nuclear power.

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Carbon Dioxide in Atmosphere Hits Record High Despite Pandemic Dip

Photo, posted August 7, 2013, courtesy of Gerry Machen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Forests And Climate Change | Earth Wise

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A carbon sink is anything that absorbs more carbon from the atmosphere than it releases.  Examples of carbon sinks include the ocean, soil, and plants.  In contrast, a carbon source is anything that releases more carbon into the atmosphere than it absorbs.  Volcanic eruptions and burning fossil fuels are two examples.

Forests are among the most important carbon sinks.  Trees remove carbon from the air and store it in their trunks, branches, and leaves, and transfer some of it into the soil.  But in many regions, deforestation, forest degradation, and the impacts of climate change are weakening these carbon sinks. As a result, some climate activists advocate for large-scale tree-planting campaigns as a way to remove heat-trapping CO2 from the atmosphere and help mitigate climate change. 

But according to a new study recently published in the journal Science, planting new trees as a substitute for the direct reduction of greenhouse gas emissions could be a pipe dream.  While planting trees is easy, inexpensive, and can help slow climate warming, the ongoing warming would be simultaneously causing the loss of other trees.  Instead, the research team says it makes more sense to focus on keeping existing forests healthy so they can continue to act as carbon sinks, and to reduce emissions as much as possible and as quickly as possible.        

But keeping forests healthy will require a paradigm shift in forest management.  Instead of trying to maintain forests as they were in the 20th century, the research team says forests need to be managed proactively for the changes that can be anticipated. 

One thing is clear: We cannot plant our way out of the climate crisis.

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Forests and climate change: ‘We can’t plant our way out of the climate crisis’

Photo, posted August 9, 2015, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Blue Carbon Credits | Earth Wise

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Carbon credits have been around since the late 1990s.  The idea is to offset carbon emissions from some carbon emitting activity – anything from a wedding in California to a factory operating in Minnesota – by buying carbon credits earned from a carbon-absorbing activity, such as planting trees in the Amazon.

Blue carbon credits are credits earned by increasing the carbon stored in coastal and marine ecosystems. Coastal ecosystems such as mangroves, tidal marshes, and seagrass meadows in fact sequester and store more carbon per unit area than terrestrial forests and are increasingly being recognized for their important role in mitigating climate change. 

Blue carbon credit awards have to date been relatively few and far between and have mostly been granted for mangrove restoration efforts.  But mangrove projects are now ramping up dramatically in scope.  Scientists are working hard to analyze the amount of carbon in other ecosystem types – seagrasses, salt marshes, seaweeds, and seafloor sediments – so that these systems can also enter the carbon credit market.

Over the past 20 years, conservation scientists have spread over 70 million seeds in the bays of Virginia to restore over 9,000 acres of seagrass meadows that were devastated by disease in the 1930s.  The restored meadows are absorbing nearly half a ton of CO2 per acre. 

The rules to allow for blue carbon credits are recent and evolving, which is a big deal. The market may currently be small, but it is growing exponentially.  But as important as carbon credits are, it is still paramount to decarbonize before turning to offsets for existing emissions.

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Why the Market for ‘Blue Carbon’ Credits May Be Poised to Take Off

Photo, posted July 2, 2009, courtesy of Nicolas Raymond via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tropical Species Moving North | Earth Wise

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Climate change is leading to warmer winter weather throughout the southern U.S., providing opportunities for many tropical plants and animals to move north.  A new study by scientists at UC Berkeley looked at the changing distribution of tropical species driven by the warming climate.

Some species are appreciated in their new locations, such as sea turtles and the Florida manatee, which are gradually moving northward along the Atlantic Coast.  Others, like the invasive Burmese python are not so welcome.  That goes double for many insects, such as the mosquitoes that carry diseases like the West Nile virus, Zika, dengue, and yellow fever, as well as beetles that destroy native trees.

The transition zone, northward of which experiences freezes every winter, has always been a barrier to species native to more temperate places.  For most organisms in such places, if they freeze, they die.  Cold snaps like the recent one in Texas usually don’t happen for decades and are now likely to be less and less frequent.  In the meantime, tropical species can get more and more of a foothold and maybe even develop populations that can tolerate more cold extremes in the future.

The warming climate is leading many plant species to expand their ranges, in some cases pushing out native species.  The general story is that the species that do really well are the more generalist species whose host plants or food sources are quite varied or widely distributed and can tolerate a wide range of conditions.  By definition, they tend to be the pest species.

We need to prepare for widespread shifts in the distribution of biodiversity as climate, including winter climate, changes.

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Tropical species are moving northward as winters warm

Photo, posted May 7, 2010, courtesy of Jim Reid / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Not All Trees Cool The Planet | Earth Wise

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A new study from Clark University has found that deforestation does not always contribute to planetary warming, as is generally assumed.  The researchers have found that there can be places where removing trees actually cools the planet.

Forests soak up carbon dioxide from the air and store it in the trees themselves and in the soil.   This process is important for slowing the accumulation of greenhouse gases in the atmosphere.

The new research focuses on a different effect that forests have on climate.  They are darker than other surfaces, which causes them to absorb more sunlight and retain heat.  This is known as the albedo effect.

In most places, the absorption of carbon outweighs the albedo effect and forests help cool the planet.  But there are some locations, including the Intermountain and Rocky Mountain West, where more forest actually leads to a hotter planet when both processes are taken into account.  State-of-the-art satellite remote sensing allowed the researchers to quantify the effects of forest loss in the United States.

The upshot of this research is that large-scale tree-planting initiatives, such as Canada’s 2Billion Trees Initiative and the Nature Conservancy’s Plant a Billion Trees campaign need to make sure to put the right trees in the right places.

Every year, about a million acres of forest are being converted to non-forest across the lower 48 states as a result of suburban and exurban expansion and development.   It is important to take into account the albedo effect in trying to replace the climate-cooling capabilities of these disappearing forests by planting more trees.

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Clark geographer Christopher Williams: More trees do not always create a cooler planet

Photo, posted June 5, 2017, courtesy of Todd Petrie via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Allergies | Earth Wise

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According to a new study published in the Proceedings of the National Academy of Sciences, an addition to the many hardships that climate change is causing around the world is the fact that it is making allergy season worse.

Researchers have found that there is a strong link between planetary warming and pollen seasons.  The combination of warming air and higher levels of carbon dioxide in the atmosphere has caused North American pollen seasons since 1990 to start some 20 days earlier, on average, and to have 21% more pollen.

The most pronounced effects were seen in Texas, the Midwest, and the Southeast.  The effects were less obvious in the northern United States, including New England and the Great Lakes states.  The greatest pollen increases came from trees, as opposed to grasses and weeds.

Allergies do not just trigger sniffles and sneezes; they have serious effects on public health in the form of asthma and other respiratory conditions.  Studies have shown that students do less well in school during peak pollen season.  Of special concern at the moment is that high-pollen periods have been associated with greater susceptibility to respiratory viruses.  The U.S. has nearly 25 million people with asthma and 19 million adults reported hay fever in the past 12 months.  Research suggests that the early onset of pollen season correlates with a higher risk of hospitalization for asthma.

There are far fewer pollen monitoring stations than those measuring particle pollutants and air quality.  As the climate warms, we need to pay more attention to pollen as an airborne pollutant.

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Achoo! Climate Change Lengthening Pollen Season in U.S., Study Shows

Photo, posted May 18, 2012, courtesy of Forest Wander via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Street Trees And Depression | Earth Wise

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According to a study published in the journal Jama Network Open last fall, the COVID-19 pandemic has tripled the rate of depression in U.S. adults in all demographic groups. 

Previous studies have demonstrated that greenspaces in urban areas can have a positive effect on those people experiencing mental ill health. But most of those studies used self-reporting measures, which makes it difficult to compare results and draw conclusions.

As a result, an interdisciplinary research team from three research organizations in Germany tried to improve upon the work by involving an objective indicator: prescriptions of antidepressants.  To figure out whether greenspaces – in this case street trees – could positively influence mental health, the researchers focused on how the number of street trees and their proximity to homes correlated to the number of prescribed antidepressants.

After analyzing data from nearly 10,000 people living in Leipzig, Germany, and combining the findings with data on city street trees, researchers were able to identify an association between antidepressant prescriptions and the number of street trees.  The results were controlled for other factors known to be associated with depression, such as employment, gender, age, and body weight.

Having more trees within 100 meters of the home was associated with a reduced risk of being prescribed antidepressants.  The association was especially strong for groups of people deprived of street trees. 

Street trees in urban cities can not only serve as a nature-based solution for good mental health, but they can also contribute to climate change mitigation and biodiversity conservation.

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Street trees close to the home may reduce the risk of depression

Photo, posted August 17, 2011, courtesy of Aleksandr Zykov via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Search For Lingering Ash | Earth Wise

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Ash trees are some of the most important plants along riverbanks and in wetlands.  There are three ash species in North America:  the white, green, and black ash.  Unfortunately, all three species are critically endangered because of the emerald ash borer.

The emerald ash borer is an exotic beetle from Asia that first showed up in the U.S. in southeastern Michigan in the summer of 2002.  The adult beetles do little damage but the larvae feed on the inner bark of ash trees and disrupt the tree’s ability to transport water and nutrients.  The beetles are now found in 35 states and 5 Canadian provinces and have killed hundreds of millions of ash trees.

The greatest hope for preserving ash tree species relates to lingering ash, which are those rare trees that have managed to survive the onslaught of the emerald ash borer. The idea is that those trees have some natural genetic resistance to the borer.  Getting seeds and cuttings from lingering ash and propagating them at nurseries may be the only way to get ash trees back into the natural landscape.

Lingering ash are extremely rare and therefore very hard to find.  As a result, researchers are reaching out to the public to help with the search and report the presence of these surviving trees in woodlands.

Researchers want to find large, mature trees left among those that were killed by the invasive insect and therefore display great resilience.  In Kentucky, university and Division of Forestry researchers are making use of software tools to engage the assistance of the public. An app called TreeSnap allows people to provide data on trees that they find in their community, on their property, or out in the wild.

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Researchers Ask Public for Help Finding Lingering Ash Trees

Help Our Nation’s Trees!

Photo, posted May 31, 2014, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe’s Green Deal: Bad For The Planet? | Earth Wise

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In 2019, the European Union announced the “Green Deal,” a comprehensive program aimed at making Europe the first climate-neutral continent, implementing environmentally friendly transport, increasing recycling, and expanding renewable energy.

The Green Deal involves significant changes to European agriculture.  Over the next ten years, under the ambitious environmental program, at least a quarter of all agricultural areas will be farmed organically, the use of fertilizers and pesticides greatly reduced, 3 billion trees planted, 15,000 miles of rivers restored, and the population declines of pollinators reversed.

However, in a recent article published in Nature, scientists at the Karlsruhe Institute of Technology show that this Green Deal might actually be a bad deal for the planet.

The problem is that the EU is likely to basically be outsourcing environmental damage by its high imports of agricultural products.

According to the Karlsruhe study, the EU annually imports millions of tons of agricultural products, as much as 20% of its produce and much of its meat and dairy products.  Quite often, these imports come from countries whose environmental laws are far less stringent than those in Europe.

The EU cannot impose environmental standards on other countries, but it can demand that goods entering the European market meet EU requirements.  The study points out that Europe’s carbon footprint has to be evaluated on a global basis.  If the EU is truly to become a climate-neutral continent, it must include foreign trade goals and requirements in its environmental programs.  Otherwise, Europe will simply be outsourcing its environmental problems and will continue to cause damage to the planet.

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Green Deal: Good for a Climate-neutral Europe – Bad for the Planet

Photo, posted July 17, 2009, courtesy of Edmund Garman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why Do Trees Change Color? | Earth Wise

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We had a particularly colorful fall in the Northeast this year.  Almost everywhere you looked, there were brilliant displays of yellow, orange, and red.  The colors of fall are a result of chemistry and environmental events that may have taken place many months in the past.

The color of leaves comes from 4 pigments whose effects are governed by photosynthesis.  The one that is actually used in photosynthesis is chlorophyll and it causes leaves to be green.  But when a tree begins to prepare for dormancy, it stops producing chlorophyll, the green pigmentation fades, and the other pigments that were already in the leaves become visible.

There are xanthoplylls, which are the yellow pigments that are seen the most in fall trees.  They are the same pigments that color egg yolks and sometimes parts of the human eye.  They are only produced by plants and appear in humans and animals only through consumption.

There are carotenes, which are the orange pigments found in fruits and vegetables, such as carrots, oranges, some bell peppers and squashes.

And there is anthocyanin, which is the pigment found in blueberries, blackberries, and red or violet roses.  Its color depends on the pH level of the plant; higher pH leads to darker color.  This is the pigment seen in red maples, black cherry trees, Shumard oaks, and more.  Only 10% of trees in temperate climates produce anthocyanin and its red pigmentation and most of those trees are in New England.

All these pigments serve purposes.  They help trees absorb light energy, prevent sun damage, and even regulate how much energy chlorophyll produces.

There are complicated chemical and environmental factors at play in fall foliage but when they come together like they did this year, it’s a magnificent spectacle.

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Why Do Trees Change Color?

Photo, posted October 17, 2020, courtesy of John Brighenti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dust And Himalayan Glaciers | Earth Wise

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Glaciers in the Himalayas have been melting and retreating, as have glaciers around the world.  As is the case elsewhere, human-driven climate change is a major factor.  But at the lofty heights of the Himalayas, warming temperatures are not the biggest culprit.  Black carbon – released into the air by burning fossil fuels or biomass such as plants, trees, and shrubs – darkens the snow and causes it to absorb more of the sun’s heat.  A recent study by an international team of scientist has identified another important factor:  dust.

An estimated 5 billion tons of desert dust enters the Earth’s atmosphere every year.  Dust from places like Saudi Arabia gets picked up by spring winds and gets deposited on the western sides of mountains, where it can make the air 10 times more polluted than most European cities.  Dust blows across industrial and desert areas in the Indian subcontinent and the Middle East and lands in the Himalayas.  According to the new study, this dust is often the dominant cause of snow melt in those areas.

Desert dust causes snow melt in the same way that black carbon does.   Dirty snow absorbs sunlight more easily than clean snow.

Desert dust is a natural part of Earth’s systems, but the amount of it in the atmosphere has steadily increased since the Industrial Revolution, when humans greatly expanded into desert areas and broke through surface crust that held large amounts of dust in place.

There is not much we can do about desert dust, short of eliminating deserts.  But the disappearance of the Himalayan ice pack – which sustains over a billion people – can be mitigated by reducing greenhouse gas emissions to address climate change .

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Himalayan glaciers melting because of high-altitude dust

Photo, posted March 13, 2018, courtesy of Sarunas Burdulis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Light And Nature | Earth Wise

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Most of us are familiar with air pollution, water pollution, soil pollution, and noise pollution.  But it turns out that light can also be a pollutant as well. 

Light pollution is a consequence of industrial civilization.  Sources of light pollution include building interior and exterior lighting, advertising billboards, factories, commercial properties, streetlights, and sporting venues.      

According to findings in a new report from the University of Exeter, artificial nighttime lighting has a wide range of effects across the natural world and should be limited wherever possible.  The research team analyzed more than 100 studies and found that artificial lighting has widespread impacts on both animals and plants. 

In the study, which was funded by the Natural Environment Research Council in the U.K., researchers consistently found changes to animals’ bodies and behavior as a result of artificial lighting.  In particular, levels of the sleep cycle-regulating hormone melatonin were reduced by exposure to artificial lighting at night in all animal species studied. 

Exposure to artificial nighttime lighting also affected the timing of animals’ activities.  For rodents, which are largely nocturnal, the duration of activity was often reduced by exposure to nighttime lighting.  On the other hand, for diurnal birds, exposure to nighttime lighting led to an extension of the duration of their activities.  

Previous studies have found other wide-ranging impacts of nighttime lighting, from reducing pollination by insects to trees budding earlier in spring.  

Artificial nighttime lighting is human driven and very disruptive to the natural world.  While there’s no off switch for the planet, we could reduce the amount of light pollution drastically with no impact on our lives. 

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Artificial night lighting has widespread impacts on nature

Photo, posted July 29, 2017, courtesy of spacedust2019 via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fuel From Lignin | Earth Wise

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Lignin is an organic polymer that provides the rigid structure of plants and is what gives wood and bark their characteristic properties.  Lignin typically comprises between 20 and 35% of the mass of wood.  The two major substances extracted from trees, grasses, and other biomass materials are cellulose and lignin.  Cellulose is used to make paper, bioethanol, and other products, but lignin is largely unused because it is difficult to break down into useful substances such as feedstocks for fuels.  As a result, lignin is largely wasted.  Worldwide, some 50 million tons of lignin are produced from paper and bioethanol manufacturing each year and almost all of that is simply burned to generate heat.

Lignin can be broken down using pyrolysis techniques at high temperatures to create bio-oils, but those oils lack sufficient hydrogen and contain too much oxygen to be useful as fuels.  There is a process called hydrodeoxygenation that adds hydrogen and removes oxygen, but it requires high temperatures and very high pressures as well as producing char and tar that reduces the efficiency of the process.

Researchers at Georgia Tech recently published work describing a new process for turning lignin into useful products.  They developed a dual catalyst system of super-acid and platinum particles that adds hydrogen and removes oxygen from lignin bio-oil and makes it useful as a fuel and source of chemical feedstocks. 

The new process could help meet the growing demand for bio-based oils as well as helping the forest product, paper, and bioethanol industries by providing an additional revenue stream from what previously was a waste product.

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New Process Boosts Lignin Bio-oil as a Next-Generation Fuel

Photo, posted August 16, 2017, courtesy of evcabartakova via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Do Forests Grow Better With Our Help? | Earth Wise

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Tree planting has become a worldwide cause.  International calls to plant a trillion trees to combat climate change have led to multiple initiatives by countries around the world.  Even the current U.S. administration, with support from businesses and nonprofits has promised to plant over 800 million trees across an estimated 2.8 million acres.  Planting trees is widely seen to be a vital nature-based solution to climate change; a way of moderating its effects as the world works to reduce carbon emissions.  However, recent studies have created some pushback from that view.

The new studies are not opposed to trees.  What they have revealed is that allowing forests to grow back naturally is a better strategy than planting trees.  The new data has shown that, among other things, estimates of the rate of carbon accumulation by natural forest regrowth have on average been 32% too low and, for tropical forests, have been 53% too low.

A new study published in Nature identified 1.67 billion acres that could be set aside to allow trees to regrow.  It excludes land under cultivation or built on, along with various existing valuable ecosystems. 

Natural regrowth allows nature to select which tree species take hold and turns out to happen quite rapidly and in a widespread manner.  The great thing about natural restoration of forests is that it often requires nothing more than human inaction.  Because it requires no policy initiatives, investments, or oversight, data on its extent is rather scarce.  But the data we have reveals that wherever forests have been allowed to recover on their own, it appears to happen rapidly and with great success.

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Natural Debate: Do Forests Grow Better With Our Help or Without?

Photo, posted September 5, 2015, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saharan Dust And The Amazon | Earth Wise

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We talk about globalization primarily in the context of how human activities connect up distant parts of the world.  But there are natural processes that are global in scope as well.  One of these is the transportation of mineral-rich dust from the Sahara Desert in North Africa to the Amazon Basin in South America.

Every year, this dust is lifted into the atmosphere by winds and carried on a 5,000-mile journey across the North Atlantic.  It turns out that this dust plays a critical role in the Amazon basin ecosystem.  The Amazon Basin in turn plays a major role in global climate.  Its trees and plants remove huge quantities of carbon dioxide from the atmosphere and stores the carbon in vegetation.

The transcontinental journey of dust is important because of what is in the dust.  The dust picked up from ancient lake beds in Chad comes from rock minerals formed by dead microorganisms and is loaded with phosphorus.  Phosphorus is an essential nutrient for plant growth and is in short supply in Amazonian soils.  Local nutrients like phosphorus in the Amazon mostly come from fallen, decomposing leaves and organic matter but tend to be washed away by rainfall into streams and rivers. 

Studies have shown that the phosphorus that reaches Amazon soils from Saharan dust is essential to replace the amounts lost to rain and flooding.

Recent research has found that the quantities of dust transported to South America are inversely linked to rainfall in North Africa and is likely to be affected by climate change.  Changes in dust transport could affect plant growth in the Amazon and the amount of CO2 removed from the atmosphere.  The forces that affect the climate are truly global in nature.

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Study quantifies Saharan dust reaching Amazon

Photo, posted April 19, 2011, courtesy of CIAT via Flickr. Photo credit: ©2011CIAT/NeilPalmer.

Earth Wise is a production of WAMC Northeast Public Radio.

An Environmental Victory In Cameroon | Earth Wise

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The Ebo Forest in Cameroon is one of the last intact forests in central Africa and is a biodiversity hotspot, home to hundreds of rare plants and animal species, including tool-using Nigeria-Cameroon chimpanzees, western gorillas, forest elephants, red colobus monkeys, and giant goliath frogs.  The 600 square miles of mountain slopes and river valleys are covered by thick tree canopies that shelter a fascinating array of species.

This past July, Cameroon Prime Minister Joseph Dion Ngute signed a decree that turned half of the Ebo Forest into a so-called forest management unit, meaning that the government could begin to sell logging concessions.

However, on August 11, Ngute, at the direction of President Paul Biya, withdrew the decree, suspending any logging plans.  President Biya also ordered a delay to reclassify an additional 160,000 acres of the Ebo, which might have opened up even more forest for logging.

Apart from its rich biodiversity, the Ebo Forest is culturally and societally important for the Banen Indigenous people, who consider it to be their sacred ancestral home.  The Banen were ousted from the forest in the 1960s but took up settlements just a few miles from its borders.  They still rely on the forest for food and medicines.  Meanwhile, the proximity of the forest to big cities makes it an easy target for bushmeat poachers.

Both conservation groups and indigenous leaders welcomed the withdrawal of the decree but remain concerned about the future of the Ebo Forest.  Conservation groups hope that the international community will seize the opportunity to work with the government of Cameroon to make the Ebo Forest a permanent showcase for long-term conservation in harmony with very challenged communities.

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Cameroon Cancels Plan to Log Half of the Ebo Forest, a Key Biodiversity Hotspot in Central Africa

Photo, posted September 17, 2005, courtesy of Salva le Foreste via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers And The Warming Arctic | Earth Wise

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Beavers have a remarkable ability to transform landscapes.  Using their sharp teeth, they fell trees and shrubs and build dams, which cause small valleys to fill with water and form new lakes.  Some of these lakes measure five or ten acres in size, or even more.  And beavers are very efficient builders; they often build their dams at precisely those points where can they have the greatest effect with the least effort.

Scientists studying beaver activity in the Arctic regions of Alaska have found that the changing climate is leading to a substantial increase in beaver populations and their effect on the landscape.

In 2018, researchers found that the beavers living in a 7,000 square-mile area in northwest Alaska had created 56 new lakes in just five years.  Thanks to rising temperatures, more and more habitats offer the shrubs that beavers need for food and building material.  In addition, the lakes, which used to freeze solid, now offer beaver-friendlier conditions.  Also, beavers are not hunted as intensively as in the past.

The scientists were surprised that beavers have seized the opportunity so intensively.  There is basically an exponential growth in beaver dams.  This is actually a worrisome situation.  Forming all these new lakes degrades ice-rich permafrost in the area.  In the Kotzebue region of Alaska, the overall water area has increased by more than 8% over the past 17 years, and roughly two-thirds of that is due to beavers.

The degradation of the Arctic’s permafrost is a dangerous situation and it appears that anyone who wants to predict its future has to keep the activity of beavers in mind.

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Beavers gnawing away at the permafrost

Photo, posted June 23, 2018, courtesy of Becky Matsubara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tree-Planting Is Not Necessarily A Good Thing | Earth Wise

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There is no question that forests have a major role in efforts to combat climate change as well as to slow biodiversity loss.   As a result, tree-planting on a massive scale has gained traction as a strategy and there have been major commitments made to plant billions of trees around the world.

A new study at Stanford University has rigorously analyzed the potential effects of these efforts and has found some significant problems.  For example, the Bonn Challenge, which seeks to restore an area of forest more than eight times the size of California over the next 10 years, has 80% of its commitments in the form of  planting monoculture tree plantations or a limited mix of trees that produce fruit and rubber, rather than restoring natural forests.   The problem is that plantations have significantly less potential for carbon sequestration, habitat creation, and erosion control than natural forests.  The potential benefits of the planting dwindle further if planted trees replace natural flora – forests, grasslands, or savannahs – which are ecosystems that have evolved to support local biodiversity.

The study looked at previous policies that created subsidies for planting trees.  Chile’s Decree Law, in effect from 1974 to 2012, has served as a model for similar policies in a number of countries.  Those subsidies further reduced native forest cover by encouraging the establishment of plantations in places where forests might have naturally regenerated.  The subsidies expanded the area covered by trees, but decreased the area of native forests.

The study recommends that nations should design and enforce their forest subsidy policies to avoid undesirable ecological impacts and actually promote the recovery of carbon- and biodiversity-rich ecosystems.

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Poorly designed tree-planting campaigns could do more harm than good, according to Stanford researcher and others

Photo, posted April 28, 2016, courtesy of the U.S. Department of State via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Family Forests And Climate Change | Earth Wise

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Climate experts consider sequestration and storage of carbon in trees to be among the most affordable and scalable natural climate solutions.  If implemented globally, trees could provide a third of the near-term climate change mitigation needed to meet the terms of the Paris Agreement.

Small family-owned forests make up 38% of U.S. forests, a total area 1.5 times the size of Texas and more than any other ownership type.  Most small landowners want to do right by their land, but they rarely have access to the expertise or resources needed to optimize their forests for carbon sequestration.

This spring, the Nature Conservancy, the American Forest Foundation, and the Vermont Land Trust announced two new programs, funded in part by a $10 million grant by Amazon, that will provide funds to small landowners to grow larger, healthier forests.

Few forests are managed for carbon sequestration.  Practices like fast logging rotations, so-called high-grading that strips out the largest, most valuable trees, and rampant invasive species all compromise the ability of a forest to lock away carbon.  It turns out that most small landowners would like to do better, but they don’t have the expertise or the financial resources to implement sustainable management.

Existing carbon markets are not geared towards small forest owners.  Their payments are tiny and the required contract terms are onerous.  The Family Forest Carbon Program commits landowners for only 10 to 20 years.  Typical landowners won’t get a windfall.  A 100-acre landholding would stand to earn around $24,500 over 20 years. 

If these programs can sign up 20% of U.S. forest landowners, it could offset the emissions from 6 million cars.

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Web Links

How Small Family Forests Can Help Meet the Climate Challenge

Photo, posted July 14, 2013, courtesy of Joshua Mayer via Flickr.

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