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Abandoned farmland and the environment

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Abandoned farmland has been increasing dramatically in recent decades.  Estimates are that a billion acres – an area half the size of Australia – have been relinquished from cultivation globally.  While more and more of the tropics have been cultivated in recent times, the global amount of land used for agriculture has been in decline since 2001.  In the past 30 years, arable land in the United States has declined by almost a sixth.  The situation in Europe is similar.  Huge amounts of the former Soviet Union now lie abandoned. 

Farmland is abandoned for various reasons.  It may suffer from damaged soil so that crop yields are too low to be worth the effort.  Farm owners may become too old or be physically unable to continue farming.  Many younger people head for jobs in the cities and more attractive opportunities.  Wars, natural and man-made disasters, and political turmoil have all contributed.

Another form of largely ignored lands are so-called degraded forests.  These are forests that were logged in the past but are no longer productive and aren’t protected either.  These places also represent unused land with great potential value.

Ecologists point to the potential of these lands as neglected resources for rewilding efforts, improving biodiversity, and for increasing natural ways to capture carbon.  Left to its own devices, nature will usually reclaim abandoned places.  This generally provides benefits for biodiversity and climate.  But mapping, studying, managing, and protecting the increasingly vast tracts of abandoned land could increase their potential to contribute to climate change mitigation and the restoration of species and their habitats.

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Abandoned Lands: A Hidden Resource for Restoring Biodiversity

Photo, posted January 26, 2023, courtesy of Larry Syverson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Deer vs. caribou

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The combination of a warming climate and human disruption of traditional habitats has been causing changes in the ranges of many animal species.  Over the past century, white-tailed deer have greatly expanded their range in North America.  Researchers from a group of Canadian institutions have been investigating the expansion of the deer in the boreal forest of Western Canada.  A five-year study used 300 wildlife cameras throughout the region to track the activities of large mammals.

Climate change has created milder winters and habitat alteration from forestry and energy exploration have created new food sources for deer. 

The expansion of deer in the forest has not been a good thing for the woodland caribou. The species was designated as threatened in 2002.  As of 2011, only 34,000 remained in the region.  Deer are ecosystem disruptors, in this case disrupting existing predator-prey dynamics.  Areas with more deer typically have more wolves and wolves are predators of caribou.  Deer can handle high predation rates, but the already threatened caribou cannot.

Understanding the relative roles of climate and human land use is essential in efforts to recover caribou populations.  It is complicated because further north, the climate becomes harsher and human land use decreases.  The debate over the relative effect of climate or habitat change is one of the most pressing issues facing ecologists globally as they pursue efforts for ecosystem restoration.

In any case, winter severity is expected to decline as climate change progresses.  Therefore, deer are expected to keep expanding northward and increasing in abundance, which means increasing risk to caribou.

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Deer are expanding north, and that’s not good for caribou

Photo, posted January 12, 2016, courtesy of Gerry via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Oases and desertification

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Oases are important sources of water for people, plants, and animals in the world’s desert areas.  In fact, oases sustain 10% of the world’s population despite taking up only about 1.5% of land area.  They form when groundwater flows and settles into low-lying areas or when surface meltwater flows down from nearby mountains and pools.

New research from the Chinese Academy of Sciences has found that oases added 85,000 square miles of new area from 1995 to 2020, mostly from artificial expansion projects, but over the same period lost 52,000 square miles from desertification and water scarcity.  The net gain of 33,000 square miles is not considered to be sustainable given that it was mostly due to artificial causes.  The oasis expansion projects were in Asia but losses due to desertification were also mostly in Asia.

Today, oases are found in 37 countries.  Increases in oases mostly come from people intentionally converting desert land into oases using runoff water and groundwater pumping, creating grasslands and croplands. This mostly has taken place in China.

Human over-exploitation of dwindling groundwater can limit the sustainability of oases as can the long-term loss of glaciers.

The study highlighted ways to sustain healthy oases, including suggestions for improving water resource management, promoting sustainable land use and management, and encouraging water conservation and efficient water use.  As the climate continues to change, these efforts will be increasingly important for a significant portion of the world’s population.

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World’s Oases Threatened By Desertification, Even As Humans Expand Them

Photo, posted August 3, 2008, courtesy of Paul Williams via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind farms and land use

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Wind power has become one of the most affordable ways to generate electricity as well as being renewable and not contributing to global warming.  But there has been the perception that wind farms require a lot of land compared with fossil fuel power plants. This issue of land use has made decision-makers reluctant to invest in wind energy in many instances.

A new study by McGill University in Montreal looked at this issue and has found that land use for wind power is far more efficient than previously thought.  The study combined data from geographic information systems with machine learning models to assess land usage associated with nearly 16,000 wind turbines in the western U.S.

The study assessed the land use of 320 wind farms.  They found that wind power infrastructure (mostly the turbines themselves and the roads that lead to them) typically only uses 5% of the land area of a wind farm.  If the wind farm is sited in locations with existing infrastructure, such as on agricultural land, then it can be as much as seven times more land-efficient – meaning the amount energy produced in a given area of land impacted by the infrastructure – than a wind farm that is developed on unused land.

Previous studies of wind farm land usage assumed that all of the land where the wind farm was located was devoted to energy generation.  In reality, most of land in question is often used for other purposes, such as agriculture.

The methods developed by the researchers are potentially useable for future assessments of various energy technologies in terms of their environmental sustainability.

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Clearing the air: wind farms more land efficient than previously thought

Photo, posted September 29, 2009, courtesy of Tim Green via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Record high emissions

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The world is adding solar and wind power to the grid.   We are driving more and more electric cars.  Countries are pledging to cut back fossil fuel use.  There are highly visible international conferences on the climate crisis.   But despite all of these things, global carbon emissions from fossil fuels have risen once again in 2023, reaching all-time record high levels of more than 40 billion tons, about 1.1% more than the previous year.

In some places, including Europe and the U.S., fossil fuel CO2 emissions are falling, but globally, they are still rising.  Emissions continued to increase in India and China.  Global action to cut fossil fuel use is not happening fast enough to prevent the increasingly dangerous effects of climate change.

Global CO2 emissions include both the contributions of fossil fuel use and the effects of land use change.  Adding the two together, in 2023 the total was about 45 billion tons, basically unchanged from last year. 

Adding insult to injury are the emissions from fires.  The extreme wildfire seasons in Canada, Australia, and other places have contributed CO2 emissions much larger than historical averages.

About half of all the carbon dioxide emitted on Earth is absorbed by carbon sinks on land and the oceans.  The other half remains in the atmosphere, where levels are now averaging 419 parts per million, 51% above pre-industrial levels.

Current efforts are simply not profound enough or widespread enough to put global emissions on a downward trajectory.  Some climate policies in some places are proving effective, but much more needs to be done.

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Fossil CO2 emissions at record high in 2023

Photo, posted December 18, 2013, courtesy of Steve Nelson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Who wins: Wind or solar?

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A new study by the University of Exeter in the UK suggests that the world may have crossed a tipping point that will inevitably make solar power our main source of energy.  This data-driven model of technology seems to fly in the face of the current situation in which wind power contributes considerably more generation than solar power – by a factor of 3 in the U.S. and nearly double worldwide.

Wind and solar power both have advantages and disadvantages.  Solar power is quiet, requires little maintenance, and presents little danger to wildlife.  It is also practical for individual homes.  Residential wind power is not really a viable option for most people in most places.  But on the other hand, wind energy can produce more power than solar, can work both day and night, and can be located offshore far away from people.  On land, both wind and solar power take up lots of space and compete with other land use needs as well as countering people’s aesthetic preferences.

Both technologies continue to get cheaper over time, although solar has especially seen significant cost reductions.  The cost of solar power, which is already the cheapest form of electricity production, is estimated to fall to as low as $20 per megawatt hour over time from the current level of $40 per megawatt hour.

Wind and solar energy are on track to account for more than a third of the world’s electricity by 2030, according to the Rocky Mountain Institute.  Despite the predictions of various studies and the ambitions of specific technologies, it seems likely that wind and solar power will both play an expanding role in our energy systems for a long time to come.

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World may have crossed solar power ‘tipping point’

Photo, posted November 22, 2008, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Powering Britain with sun and wind

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The United Kingdom is quite small in size compared with the US, but its population of 67 million makes it a fairly large country with substantial energy needs.  A recent study by Oxford University looked at the ability of wind and solar power to provide for those energy needs over the course of time.

According to the study, Britain’s energy needs could easily be met entirely by the two sources of clean power.  Wind and solar can provide significantly more energy than the highest energy demand forecasted for 2050 and nearly 10 times the current electricity demand. 

Britain currently requires 299 TWh per year.  The Oxford study found that wind and solar could generate as much as 2,896 TWh per year. Furthermore, the researchers stated that these estimates are intentionally conservative, taking into account concerns around land use and the visual impact of installations.

The analysis assumes that offshore wind would produce nearly three-quarters of the energy required.  Onshore wind would contribute about 7%, while taking up only 0.07% of the country’s land.  Utility-scale solar would add about 19% of the power.  The small remainder comes from rooftop solar.  The researchers do point out that the power grid would require significant upgrades to handle all this renewable energy and that there would need to be appropriate quantities of energy storage. 

According to the authors of the study, achieving these results is a question of ambition rather than technical feasibility.  So far, the UK government has not been aggressive in making the transition to renewable energy.

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Wind and solar power could significantly exceed Britain’s energy needs

Photo, posted November 4, 2021, courtesy of Steve Knight via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Why Are Insect Populations Declining? | Earth Wise

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The world is experiencing a decline in overall insect populations as well as a collapse in insect diversity.  A recent special issue of the journal Biology Letters discusses the major causes of this alarming trend.

According to the study, the primary causes of the worldwide decline in insect biomass are land-use intensification in the form of greater utilization for agriculture and building development, climate change, and the spread of invasive animal species as a result of human trade.

The study concludes that it is not just these factors that are driving the global disappearance of insects, but also that these three factors are interacting with each other.  For example, ecosystems that are deteriorated by humans are more susceptible to climate change and so are their insect communities.  Similarly, invasive species can establish themselves more easily in habitats damaged by human land-use and displace native species.  Many native insect species decline or go extinct while others – often invasive species – thrive and increase, leading to decreasing insect diversity.  Warming temperatures are making many locations undesirable for various insect species and they often cannot migrate to anyplace better.

Declining insect populations and diversity results in concomitant declines in plant species that depend on pollinators.  This in turn threatens the stability of entire ecosystems.

The researchers advocate for continued monitoring of insect diversity across many habitats and countries and propose the creation of a network of interconnected nature reserves such that species can move from one to another. 

We often think of insects as pests, but they are a crucial part of the world’s ecosystems.

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The reasons why insect numbers are decreasing

Photo, posted April 17, 2011, courtesy of Dean Morley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Can All Plant Species Survive? | Earth Wise 

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Many animal populations around the world are struggling and people are mostly to blame.  Species are declining because of all sorts of things including changes in land and sea use, pollution, invasive species, and climate change.

Like many animal species, plants are also struggling to adapt to a human-dominated world.  Plants provide the planet with food, oxygen, and energy, and are used to produce fibers, building materials, and medicines.  Even though plants are easier and cheaper to protect, they are often overlooked in conservation efforts. 

According to a paper recently published in the journal Trends in Plant Science, preventing all future land plant extinctions across the globe is possible with the right approaches.  The author of the paper, Richard Corlett of the Xishuangbanna Tropical Botanical Garden in China, writes that “if zero extinction is potentially achievable for plants, a less ambitious target would be inexcusable.” 

According to the paper, one big barrier in plant conservation is the lack of trained specialists, especially in tropical areas where there is a backlog of unidentified species.  It’s likely that many “dark extinctions,” which is when species slip away without us knowing they existed, have already occurred.

Another roadblock in preventing plant extinctions is information access, which can be solved by building an online “metaherbarium.”  This collaborative database would link digitized records from herbarium specimens with photographs, status assessments, and recovery plans.

Finally, the creation of “microreserves” – which are tiny pieces of protected land designed to get around space constraints – would further contribute to effective conservation of targeted plant species. 

Zero plant extinctions should be the goal.   

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‘Zero plant extinction’ is possible, says plant ecologist

Photo, posted May 16, 2008, courtesy of Andrew Otto via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How To Meet Protected Land Targets | Earth Wise

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More than half of the world’s countries have set a target of setting aside 30% of land and sea areas across the globe for conservation by 2030, in order to preserve and protect nature and essential services to people.  This pledge creates some difficult questions to answer.

What sorts of land should be protected and where should it be located?  What effects of these new land protections will there be on carbon emissions and the climate and on land usage for food production and energy generation?  Policymakers have to grapple with such questions in order to move forward on these ambitious biodiversity protection goals.

A recent study by the Lawrence Berkeley National Laboratory attempts to answer many of these questions.  The study found that meeting the 30% goal could lead to substantial regional shifts in land use and, in some cases, still fail to protect some of the most important biodiversity hotspots.

Protecting land entails tradeoffs with other land uses and can have negative impacts on the agricultural sector as well as land use for bioenergy crops and forest land use for timber.

In particular, the study found that the amount of land used for crops for conversion into biofuels could be significantly impacted by doubling current protected areas while still preserving the amount of land used for food crops.  This is particularly true for land in Russia and Canada.

The study also found that while it may be possible to meet the 30% target by only protecting agriculturally unsuitable land, it may not end up protecting many of the world’s 36 identified biodiversity hotspots.  The uneven distribution of species has a significant bearing on how to manage the conservation of biodiversity.

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Doubling Protected Lands for Biodiversity Could Require Tradeoffs With Other Land Uses, Study Finds

Photo, posted September 19, 2020, courtesy of John Brighenti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking Global Forest Changes | Earth Wise

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India is one of the most biodiverse countries in the world.  An estimated 47,000 plant species and 89,000 animal species can be found in India, with more than 10% of each thought to be on the list of threatened species.

India is also one of the 10 most forest-rich countries in the world.  Trees cover approximately 25% of the nation.  But this is still a significant decline from years past.  In fact, between the 1890s and 1990s, a combination of rapid development and resource overexploitation caused India to lose nearly 80% of its native forest area.  Today, as India’s forests continue to disappear, researchers are trying to help preserve what forest remains. 

Using satellite-monitoring data, researchers from The Ohio State University have developed a deep learning algorithm that could provide real-time land use and land cover maps for parts of India. 

The land use monitoring system was trained using satellite data from Norway’s International Climate and Forests Initiative.  By combining this data with a global land cover map produced by Tsinghua University in China, the researcher team’s deep learning model was able to acquire a more detailed type of base map of the area.  Using their model, the researchers were able to process 10 monthly maps.  Their research was recently  presented at the annual meeting of the American Geophysical Union.   

Using these maps, the researchers were able to detect seasonal shifts across india.  These include changes to barren land, how crop land was affected by monsoons, and the distribution of forests in mountainous regions. 

Understanding the impact of these seasonal changes will help scientists better predict the effects of climate change on forests.

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Using deep learning to monitor India’s disappearing forest cover

Photo, posted January 20, 2013, courtesy of Frontier Official via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Bumblebees And Climate Change | Earth Wise

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Pollinators, such as bees and bats, are vital for global food production.  They provide an ecological service that’s necessary for the reproduction of nearly 75% of the world’s flowering plants, including more than two-thirds of global food crops.

Bumblebees are among the most important plant pollinators.  They pollinate many food crops, including apples, tomatoes, blueberries and legumes, as well as countless types of trees, shrubs, and wildflowers.

According to a new study by researchers from Simon Fraser University in Canada, temperature changes have negatively impacted most bumblebee species during the past 120 years.  The research, which was recently published in the journal Biology Letters, found that these changes in temperature had more of a negative impact than other factors such as precipitation or floral resources. 

The research team analyzed existing data on 46 bumblebee species across North America between 1900 and 2020.  The researchers created two occupancy models – one that was focused on time and the other that focused on environmental factors – to see how climate change and land-use variables impacted species’ occupancy.  They found that six bumblebee species decreased through time, 22 increased, and 18 remained stable.

Temperature changes had primarily negative impacts on bumblebees.  In fact, 37 of the 46 species studied exhibited declines or less positive occupancy increases under observed changes in temperature when compared with temperatures remaining constant.  Approximately half of the bumblebee species were negatively impacted by changes in precipitation or floral resources while the other half were positively impacted.

Bumblebee populations are changing as a consequence of climate change. 

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The American Bumblebee

Climate change negatively impacting bumble bees: Study

Photo, posted July 14, 2019, courtesy of Dmitry Grigoriev via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Kenya’s Tana River Basin | Earth Wise

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The Tana River is the longest river and most important waterway in Kenya.  It flows 620 miles from its headwaters in the Abderdare mountain range and Mount Kenya to the Indian Ocean.  The Tana River produces approximately half of the country’s electricity, and supplies Nairobi, the capital of Kenya, with 80% of its water.   

According to the United Nations Environment Programme, eight million people live along the Tana River, where coffee, tea, corn and other crops are grown for export, and fishing and cattle grazing help produce food for large portions of the country’s population. 

But the long-term ability of the river to provide these and other essential services is increasingly under threat due to many factors, including pollution, soil erosion, deforestation, and poor land use practices.   

Climate change is also complicating matters.  According to new research from the University of East Anglia, many species within the Tana River Basin will be unable to survive if global temperatures continue to rise at the current pace.  However, the study, which was recently published in the journal PLOS ONE, also found that many of these species could be saved if the world could meet the climate goals of the Paris Agreement. 

Globally, climate and land use changes are the two biggest threats to biodiversity.  According to researchers, 36% of the Tana River Basin has already been converted to agriculture. 

The research team says stronger commitments on climate change are needed from global leaders.  The climate and biodiversity crises can only be solved with urgent action to reduce global greenhouse gas emissions. 

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The impact of climate change on Kenya’s Tana river basin

Economics of Ecosystem Services of the Tana River Basin

Photo, posted August 19, 2010, courtesy of Luigi Guarino via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Land Use Change And Flooding | Earth Wise

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Land use change refers to the conversion of a piece of land’s use by humans from one purpose to another. Land use change is commonly associated with biodiversity loss and increased greenhouse gas emissions.  But how does land use change impact water cycles? 

According to researchers from the University of Göttingen in Germany, IPB University, and BMKG (both in Indonesia), the expansion of monocultures, such as rubber and oil palm plantations, leads to more frequent and more severe flooding.  The researchers explain the increase in flooding “with a complex interplay of ecohydrological and social processes, including soil degradation in monocultures, the expansion of oil palm plantations into wetlands, and the construction of flood protection dams.” 

For the study, which was recently published in the journal Ecology & Society, the research team interviewed nearly 100 Indonesian farmers, villagers, and decision-makers in Sumatra.  The team supplemented its research with data on precipitation, river and groundwater levels, soil properties, and regional mapping. 

During large-scale land use change – like plantation expansions – newly-compacted soil causes rainwater to runoff as opposed to being absorbed.  As more plantations are established in floodplains, the owners try to control flooding on their land by building barriers.  But these dams often lead to increased flooding on neighboring lands.  This understandably triggers social tensions between other farmers and plantation owners.     

In order to reduce the negative impact of land use change on the water cycle, the research team suggests soil protection and improved planning – especially in floodplains – would be a good place to start.  

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Land use change leads to increased flooding in Indonesia

Photo, posted October 8, 2018, courtesy of Artem Beliaikin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A First In The Climate Change Fight | Earth Wise

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Under a new initiative, builders in New Jersey will have to take climate change into account in order to win government approval for projects.  New Jersey is the first state in the United States to enact such a requirement, which will leverage land-use rules to control what and where developers can build, and limit the volume of pollution. 

Through executive order, New Jersey Governor Phil Murphy will require the state Department of Environmental Protection to draft new building regulations.  The changes, to be adopted by January 2022, do not require legislative approval, but could face political and legal challenges. 

Climate change is expected to have a significant impact on New Jersey and its 130 miles of coastline.  According to a recent study from Rutgers University, the sea level along the New Jersey coast rose 1.5 feet since 1911, which was more than twice as much as the global average. The sea level is expected to rise by as much as another foot by 2030.  At the same time, some coastal areas of New Jersey are gradually sinking.

The initiative by New Jersey comes on the heels of a Trump administration proposal which would allow federal agencies to not take climate change into account when evaluating infrastructure projects. The federal changes are geared towards speeding up approvals for highway construction, pipelines, oil and gas leases, and other major infrastructure projects.   

In the absence of anything resembling leadership on climate change from the federal government, it remains for states like New Jersey to continue to press ahead.  In addition to the new building initiative, New Jersey also plans to produce 100% clean energy by 2050. 

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Excluding Climate Change From Infrastructure Planning | Earth Wise

With 130-Mile Coast, New Jersey Marks a First in Climate Change Fight

Photo, posted August 27, 2016, courtesy of Rashaad Jorden via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What Is An Endangered Species? | Earth Wise

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Biodiversity is declining rapidly throughout the world and people are mostly the reason.  Species are disappearing because of changes in land and sea use, the direct exploitation of organisms, climate change, pollution, and invasive alien species resulting from globalization.  The challenges of conserving the world’s species are many and difficult.  Among these challenges are determining which species are endangered and how and when to protect them.

What constitutes an endangered species is not necessarily obvious. 

Extinction risk increases as a species is driven to extinction from portions of its natural range.  Most mammal species have already been driven to extinction from half or more of their historic ranges because of human activities.

According to a recent survey of ordinary Americans, three-quarters of participants said that a species deserves special protections if it had been driven to extinction from any more than 30% of its historic range.  This compares with the language of the U.S. Endangered Species Act that defines an endangered species as one that is “in danger of extinction throughout all or a significant portion of its range.”

Experts and decision-makers are more accepting of risks and losses because they believe greater protection would be impossibly expensive.  Decision-makers tend to be influenced by special interest groups with a vested interest in not instituting protections.

Before human activities began elevating extinction risk, a typical vertebrate species would have experienced an extinction risk of 1% over a 10,000-year period.  Current policies consider a 5% risk over 100 years to be acceptable.  Policies consider whether we can afford to protect species.  Given the dangers of declining biodiversity, we should ask whether we can afford not to.

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What Is An Endangered Species?

Photo, posted July 29, 2018, courtesy of Sergio Boscaino via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Ocean Acidification And Mass Extinction

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Since the industrial revolution, the concentration of carbon dioxide in the atmosphere has increased due to the burning of fossil fuels and land use changes.  The ocean absorbs about 30% of the CO2 that is released in the atmosphere.  As the levels of atmospheric CO2 increase, so do the levels in the ocean.

When CO2 is absorbed by the ocean, a series of chemical reactions occur, resulting in seawater becoming more acidic.  Ocean acidification threatens calcifying organisms, such as clams and corals, as well as other marine animals, like fish.  When these organisms are at risk, the entire marine ecosystem may also be at risk.

In fact, according to research recently published in the journal Proceedings of the National Academy of Sciences, fossil evidence from 66 million years ago has revealed that ocean acidification can cause the mass extinction of marine life.  Researchers analyzed seashells in sediment laid down shortly after a giant meteorite hit earth.  This strike wiped out the dinosaurs and 75% of marine species.  Chemical analysis of the shells revealed a sharp drop in the PH of the ocean over hundreds of years after the meteorite strike.  The meteorite impact vaporized rocks, causing carbonic acid and sulphuric acid to rain down, acidifying the ocean.  The strike also resulted in mass die-off of plants on land, increasing atmospheric CO2.  

Researchers found that the pH dropped by 0.25 pH units in the 100 to 1,000 years after the meteorite strike.  Alarmingly, scientists expect the pH of the ocean to drop by 0.4 pH units by 2100 if our carbon emissions continue as projected. 

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Ocean acidification can cause mass extinctions, fossils reveal

Photo, posted March 16, 2017, courtesy of Zachary Martin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shifting Ecosystems

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The Great Plains ecosystem has been shifting northward over the past fifty years, driven by climate change, wildfire suppression, energy development, land use changes, and urbanization.  The ecosystem is an area historically rich with grasslands and shrub steppe and is prime habitat for grassland birds.

According to a recent study published in the journal Nature Climate Change, the northernmost ecosystem boundary of the Great Plains has moved more than 365 miles north since 1970, amounting to about 8 miles a year.  The region’s southernmost ecosystem boundary has shifted 160 miles north, or about 4 miles a year.

The study used bird distribution data as an indicator of shifting ecosystem boundaries.  The researchers analyzed 46 years of data for 400 bird species across a 250-mile-wide strip stretching from Texas to North Dakota.  They tracked how the birds’ distributions changed as a measure of how these ecosystems were shifting.

While climate change has been a major driver of these ecosystem shifts since the 1970s, several other factors such as wildfire trends, land use changes, and invasion of tree species into grassland habitat have also played a role.  Like most things in ecological systems, the changes are likely to have multiple causes.  One cannot really separate causes like tree invasions, warming climate, and wildfires, as they are all interrelated.

Using bird distribution patterns for tracking ecosystem shifts could be a useful tool for scientists and land managers in the coming decades to give them an early warning of how habitats are changing in response to rising global temperatures and therefore allow them to take action to protect vulnerable species.

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Great Plains’ Ecosystems Have Shifted 365 Miles Northward Since 1970

Photo, posted March 24, 2017, courtesy of Rick Bohn / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Bad Year For Bees

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The latest annual nationwide survey of beekeepers in the US revealed that honeybees are still dying off at an alarming rate.  According to the survey, beekeepers across the country lost 40.7% of their honey bee colonies from April 2018 to April 2019. 

This annual loss represents a slight increase over the average annual loss of 38.7%.  Of greater concern is that winter losses of 37.7% were the highest reported since these annual surveys began 13 years ago and are almost 9% higher than the survey average.

These results are very troubling considering that the elevated losses are continuing even after a decade of intense work trying to understand and reduce colony loss.  Evidently, there has not been much progress.

The number one concern among beekeepers is varroa mites, which are lethal parasites that can readily spread from colony to colony.  These mites have been decimating bee colonies for years.  Products developed to remove mites seem to be getting less and less effective.

But mites are not the only problem for bees.  Land use changes have resulted in reduced availability of pollen sources for bees.  Add to that pesticide exposures, environmental factors, and even problems with beekeeping practices.   In addition, extreme weather conditions such as wildfires and floods are only adding to the problems facing bees.

The tools that used to work for beekeepers seem to be failing and they are already stretched to their limits trying to keep their bees alive. Honey bees pollinate $15 billion worth of food crops in the United States each year. The problems facing bees are a problem for all of us.

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U.S. Beekeepers Suffered Higher than Average Colony Loss Last Year, with Winter Losses the Highest Recorded, According to UMD-Led Annual Survey

Photo, posted June 3, 2009, courtesy of Jennifer C via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Why Choose Chicken Over Beef?

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Food production is a major driver of climate change.  It’s responsible for more than a quarter of all greenhouse gas emissions.  But the environmental impact of different foods varies greatly, and making seemingly insignificant changes can actually have significant impacts. 

According to a first-ever national study of U.S. eating habits and their carbon footprints, choosing chicken over beef will cut your dietary carbon footprint in half.

The National Health and Nutrition Examination Survey asked more than 16,000 participating Americans to name all the foods they consumed in the past 24 hours. The research team then calculated the carbon footprint of what people said they ate.  If a respondent consumed broiled beef steak, for example, researchers calculated what the carbon footprint would have been had broiled chicken been consumed instead.   

The study’s findings illustrate how making one simple substitution can significantly reduce a person’s dietary carbon footprint.  A diet’s carbon footprint is the amount of greenhouse gas emissions that result from the energy, fertilizer, land use, and other inputs necessary to produce food.

In general, animal-based foods have a bigger carbon footprint than plant-based foods.  For example, producing beef uses 20 times the land and emits 20 times the emissions as growing beans (per gram of protein), and requires 10 times more resources than producing chicken. 

According to the World Resources Institute, keeping the increase in global warming below 2°C will be impossible without limiting the global rise in meat consumption. 

Last year, the EAT-Lancet Commission report found that a radical transformation of the global food system was needed because it’s threatening the stability of the climate. 

Make a change – big or small – today. 

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Choosing chicken over beef cuts our carbon footprints a surprising amount

Photo, posted August 30, 2011, courtesy of Ken Hawkins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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