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Biosphere integrity

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Civilization has an enormous need to utilize the biosphere, that is, the regions of the surface, atmosphere, and bodies of water of the earth occupied by living organisms.  The biosphere supplies us with food, raw materials, and increasingly, climate protection.

A study by two European universities looked at functional biosphere integrity, which is essentially the plant world’s ability to regulate the state of the Earth system.  Functional biosphere integrity faces massive human interference from consumption of resources, biodiversity loss, and climate change.

Highly detailed analysis modeled water, carbon, and nitrogen flows at a fine resolution over the entire planet and provided a detailed inventory year-by-year since the year 1600.  Each area is then assigned a status based on its tolerance limits of ecosystem change.  An area can either be a Safe Operating Space, a Zone of Increasing Risk, or a High-Risk Zone.

As the Industrial Revolution took hold, the proportion of global land area where ecosystem changes went beyond the locally defined safe zone, increased.  The current analysis shows that 60% of global land areas are now out of the safe operating space and 38% are facing high risk.

Human demand for biomass continues to grow.  The Earth system is increasingly stressed as humanity channels it into its own uses through harvested crops, residues, and timber.  At the same time, photosynthesis activity is reduced by land cultivation and sealing off land with construction.  We are not good for the biosphere.

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60 percent of the world’s land area is in a precarious state

Photo, posted September 14, 2024, courtesy of Jan Helebrant via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Reindeer grazing and forest carbon

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Northern forests store a third of the world’s carbon, acting as sinks for atmospheric carbon dioxide.  Forest carbon exchange is the process whereby forests sequester carbon dioxide from the atmosphere via photosynthesis, storing it in their wood, leaves, and roots, and releasing some carbon through decomposition and respiration.  This natural cycle in forests is a critical part of the global carbon cycle and is a key factor in the mitigation of climate change.

The carbon cycle in northern forests is affected by the depth of winter snow and its duration.  It turns out that other elements of the forest ecosystem play an important role as well.  Researchers at the University of Oulu in Finland measured the impact of reindeer grazing and snow depth in Finland’s coniferous forests over a five-year period. 

There are areas in northern Finland’s forests where reindeer grazing has been excluded for decades.  In these areas, shallow snow increased carbon release.  In the same locations, deeper snow decreased carbon release.  On the other hand, in areas where reindeer grazed, carbon release remained stable regardless of changes in snow cover. 

The researchers theorize that the substantially recovered lichen cover in the ungrazed areas influences soil temperature and moisture conditions.  When combined with changing snow conditions, these factors may affect soil decomposers and, therefore, the amount of carbon released. 

The essential conclusion of this work is that multiple elements of an ecosystem, such as reindeer grazing, can buffer ecosystem functions, such as carbon exchange.    In this case, reindeer play an important role in sustaining the biodiversity of northern ecosystems. 

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Reindeer grazing can mitigate the impacts of winter climate change on forest carbon release

Photo, posted December 17, 2015, courtesy of Eco Dalla Luna via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sun powered carbon capture

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As the world struggles to implement technologies and find the political will to reduce carbon emissions, there are also ongoing efforts to find ways to capture carbon from emitting sources and from the atmosphere itself.  After capturing carbon dioxide, there is then the need to safely store it or make use of it.

Current methods for capturing and then releasing carbon dioxide are expensive and energy intensive.  In fact, some methods even require the use of fossil fuels.  Recently, researchers at Cornell University have developed a method for capturing carbon dioxide that is powered by sunlight.

The Cornell method mimics the mechanisms that plants use to store carbon which involves using sunlight to make a reactive enol molecule that grabs carbon dioxide.  

Existing chemical-based carbon capture techniques make use of amines, which are organic ammonia-derived compounds that react selectively with carbon dioxide.  But amines are not stable in the presence of oxygen and don’t last, which necessitates the energy-intensive production of more and more amines.

The Cornell method uses the same method that the plant enzyme RuBisCo uses in photosynthesis.  It is based on an inexpensive sorbent material that is capable of a high rate of carbon capture.

The researchers tested the system using flue samples from Cornell’s Combined Heat and Power Building, an on-campus power plant that burns natural gas.  The system was successful in isolating carbon dioxide.

Ultimately, they would like to stage the reaction on what looks like a solar panel, but one that would capture carbon instead of generating electricity.

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In a first, system uses sunlight to power carbon capture

Photo, posted August 8, 2015, courtesy of Holly Victoria Norval via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A biostimulant for wheat

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Feeding a global population projected to reach nearly 10 billion by mid-century is a massive challenge.  Wheat provides a fifth of the calories in the global human diet and is a significant source of protein, minerals, vitamins, and fiber.  Finding ways to increase the yield of wheat crops has great value.  However, wheat has complex genetics, which makes it difficult to improve yields by traditional breeding methods or even by genetic engineering.

Researchers at Oxford University and the nearby Rosalind Franklin Institute have developed a biostimulant that can deliver increased wheat yields of up to 12%.  It is applied as a spray and a four-year study in Argentina and Mexico demonstrated that it delivers major yield improvements irrespective of weather conditions.

The biostimulant is based on trehalose 6-phosphate (T6P), which is a natural molecule that regulates the plant equivalent of blood sugar.  T6P prompts plants to produce more starch and increases the rate of photosynthesis.

Naturally occurring T6P cannot be applied topically because it cannot cross cell membranes.  The researchers developed a membrane-permeable precursor of T6P that releases T6P into a plant in the presence of sunlight.

The biostimulant can be manufactured on an industrial scale and would be inexpensive to use. 

The researchers have created SugaROx, a spinout company whose mission is “to increase the productivity, resilience, sustainability, and profitability of crop production” using active ingredients inspired by powerful natural plant molecules.

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New biostimulant treatment significantly boosts wheat yields, field studies confirm

Photo, posted July 28, 2014, courtesy of Brad Higham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Vegetation and climate change

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Temperatures have been steadily rising around the world as a result of the increased greenhouse gas emissions from human activities.  This warming trend has led to more frequent and intense heat waves, droughts, and other extreme weather events.  Rising temperatures are also impacting human health, leading to increased risks of heat-related illnesses and a higher number of fatalities during extreme heat events.

One simple but effective way to reduce the health risks from extreme heat is to increase urban vegetation.  According to new research led by scientists from Monash University in Australia, increasing urban vegetation by 30% could save more than one-third of all heat-related deaths.  The study, which was recently published in The Lancet Planetary Health, examined more than 11,000 urban areas and found that increasing greenery could have saved up to 1.16 million lives worldwide between 2000 and 2019.

The impact of increasing urban vegetation on heat-related deaths varies by climate, greenness, socioeconomic, and demographic factors, with the greatest benefits seen in Southern Asia, Eastern Europe, and Eastern Asia. 

Vegetation has a cooling effect on temperature.  Vegetation helps regulate the Earth’s climate by absorbing carbon dioxide during photosynthesis, which helps to reduce greenhouse gases in the atmosphere. Vegetation also cools the environment through shading, moisture release, and evapotranspiration, which reduces temperatures and mitigates heat-related health risks.

Incorporating more vegetation into urban areas is a powerful solution to mitigate the impacts of climate change and protect human health.

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Increasing urban vegetation could have saved over 1.1m lives in two decades

Photo, posted July 1, 2023, courtesy of Lauri via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Engineering plants to consume more carbon dioxide

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The most abundant protein on the planet is an enzyme called ribulose-1,5-bisphosphate carboxylase/oxygenase, better known as RuBisCO.  Its critical role in photosynthesis makes life as we know it on earth possible.  What it does is convert carbon dioxide from the atmosphere into the organic matter contained in plants.

Getting plants to take up more carbon dioxide from the atmosphere is a key strategy for mitigating climate change.  Planting lots of trees is one way to do it.  Another is to get individual plants to capture more carbon dioxide.

Scientists at the University of Illinois have focused on getting plants to produce more RuBisCO which allows them to grow faster, consuming more carbon dioxide in the process.

Some plants are better than others at taking advantage of the earth’s rising carbon dioxide levels.  Among these are food crops like corn, sugarcane, and sorghum.  Such plants’ growth is not primarily limited by how much carbon dioxide is in the atmosphere but rather by how much RuBisCO is in their leaves.  The Illinois scientists tweaked genes in corn and sorghum to produce plants containing more RuBisCO.  Laboratory experiments on corn demonstrated faster corn growth.  Recent outdoor field experiments on sorghum demonstrated a 16% boost in its growth rate. 

Improving photosynthesis in this way is not only a potential strategy for increasing plants’ ability to combat climate change.  It is also a way to cope with the world’s increasing demand for food by producing crops that can grow larger and more quickly.

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Scientists Engineer Crops to Consume More Carbon Dioxide

Photo, posted April 12, 2016, courtesy of K-State Research and Extension via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Artificial plants to clean indoor air

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The average American spends about 90% of their time indoors breathing the air in our workplaces, homes, or schools.  The quality of this air affects our overall health and well- being.  Indoor air quality is an issue because many sources can generate toxic materials, including building materials, carpets, and more.  But high levels of carbon dioxide are a health hazard themselves. Indoor CO2 levels can often be 5 to 10 times higher than the already heightened levels in the atmosphere. 

Many of us make use of air purification systems, which can be expensive, cumbersome, and require frequent cleaning and filter replacements.

Researchers at Binghamton University in New York are working to develop artificial plants that consume carbon dioxide, give off oxygen, and, as a bonus, generate a little electricity. These artificial plants make use of the artificial light in the indoor environment to drive photosynthesis.  They achieve a 90% reduction in carbon dioxide levels, which is far more than natural plants can achieve.

The Binghamton researchers had been working on bacteria-powered biobatteries for various applications, but they repurposed the work into a new idea for artificial plants.  The artificial plants have “leaves” containing a biological solar cell and photosynthetic bacteria.  Their first plant had five leaves and demonstrated promising carbon dioxide capture rates and oxygen generation.  It also produced a little electricity.  If its generating capacity can be improved, it might also be useful for charging cell phones or other practical applications.

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Binghamton researchers develop artificial plants that purify indoor air, generate electricity

Photo, posted October 13, 2012, courtesy of F. D. Richards via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megafires and orchard health

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The frequent and massive megafires in places like Canada and the American west have led to a lot of research on the impact of smoke on humans but there has been less study of the effects of smoke on plant health.  Researchers at the University of California, Davis have found that trees are just as vulnerable as humans are to the harmful effects of long-term exposure to smoke.

The Davis researchers studied almond, pistachio, and walnut trees at 467 orchard sites in California’s Central Valley from 2018 to 2022.  In 2022, so-called megafires burned more than 4.2 million acres in California, pouring ash and smoke into the sky.  The researchers had been studying how trees store carbohydrates to cope with heat and drought. 

With the onset of the fires, they saw an opportunity to study how smoke affects carbohydrate levels.  Trees use stored carbohydrates to sustain them through winter dormancy and spring growth.  Trees produce carbohydrates via photosynthesis and thick smoke blocks the amount of light reaching the trees.  Beyond that, there are other aspects of wildfire smoke, such as particulate matter and ozone that appear to affect photosynthesis.

The team found that the smoke not only reduced the amount of carbohydrates in trees but also caused losses that continued even after the fires were extinguished.  This led to nut yield decreases of 15% up to 50% in some orchards.  The researchers expected to see some impact on the trees during periods when smoke was really dense but were not expecting the smoke to have such a lingering effect and result in a significant drop in yield.

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Smoke From Megafires Puts Orchard Trees at Risk

Photo, posted October 1, 2008, courtesy of Suzi Rosenberg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Carbon dioxide and wildfires

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Climate change is a key factor in the increasing risk and extent of wildfires.  Wildfires require the alignment of several factors, including humidity, temperature, and the lack of moisture in fuels, such as trees, shrubs, and grasses.  All of these factors have strong ties to climate variability and climate change.

While the global surge in wildfires is often attributed to hotter and drier conditions, a new study by researchers from the University of California – Riverside has found that increasing levels of a greenhouse gas may be an even bigger factor. 

According to the study, which was recently published in the journal Communications Earth & Environment, carbon dioxide is driving an increase in the severity and frequency of wildfires by fueling the growth of plants that become kindling.

Centuries of burning fossil fuels to produce heat, electricity and to power engines has added alarming amounts of carbon dioxide to the atmosphere.  In fact, atmospheric CO2 levels are measuring more than 420 parts per million, which is a level not seen on earth for 14-16 million years. 

Plants require carbon dioxide, along with sunlight and water, for photosynthesis.  But rising levels of CO2 in the atmosphere are driving an increase in plant photosynthesis – an effect known as the carbon fertilization effect.  This effect can make plants grow bigger and faster. 

Warming and drying are important fire factors.  These are the conditions that make the extra plant mass more flammable.  But the study found that the increase in fires during hotter seasons is driven by the CO2-fueled growth of plants.   

The researchers hope their findings will urge policymakers to focus on reducing carbon dioxide levels in the atmosphere.

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CO2 worsens wildfires by helping plants grow

Current carbon dioxide levels last seen 14 million years ago

Photo, posted January 17, 2024, courtesy of Jennifer Myslivy, BLM Fire/NIFC via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar forests

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Forests are one of the most iconic symbols of the power and diversity of nature but beyond that, their thick vegetation is crucial to the stability and balance of the Earth’s climate.  This is because the photosynthesis that powers the growth of plants removes carbon dioxide from the air.  Cutting down forests – especially the evergreen forests of the tropics – has played a significant role in the increasing climate crisis.  For this reason, many environmental initiatives focus on restoring destroyed forests and planting new trees.

But the truth is, even if we were to cover the entire surface of the planet with trees, there would still not be enough photosynthesis going on to absorb the huge surplus of carbon dioxide that people have been pumping into the atmosphere for the past 150 years.

A study by the Weizmann Institute of Science in Israel looked at the impact of erecting fields of dark covered solar panels – so-called solar forests – that would generate electricity, thereby replacing power stations that use fossil fuels.  But dark fields absorb heat which eventually returns to the atmosphere.

The question is:  what is the best use of a plot of land in terms of the effect on the climate?  Planting a forest or erecting fields of solar panels?

The answer depends on where the land is.  In arid environments, building solar farms is far more effective and practical than planting forests.  But in humid places, forests currently absorb close to a third of humanity’s annual carbon emissions. 

The study concludes that combining planting and rehabilitating forests in humid regions and erecting fields of solar panels in arid regions is the most effective strategy.

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The Solar Forest

Photo, posted December 27, 2015, courtesy of Gerry Machen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moss And Carbon Storage | Earth Wise

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All plants, including algae and cyanobacteria, carry out photosynthesis. During the process of photosynthesis, plants remove carbon dioxide from the air and release oxygen to the air.  As a result, plants play a crucial role in the fight against climate change. 

According to a new study recently published in the journal Nature Geoscience, mosses – those tiny plants often found on the ground or rocks – might be important antidotes to climate change.  The study, which was led by scientists from the University of New South Wales in Australia and the Institute of Natural Resources and Agrobiology in Spain, uncovered evidence that mosses have the potential to store a massive amount of carbon in the soil beneath them.

The researchers found that mosses sequester around seven billion tons more carbon in the soil than is stored in the bare patches of soil typically found near them.  To put that figure in perspective, that is six times the annual global carbon emissions caused by global land use change, which includes things like deforestation, urbanization, and mining.  The researchers also found that moss-covered soil possessed heightened levels of vital nutrients and fewer instances of soil-borne plant pathogens on average compared to moss-less soil.

Mosses cover an area of more than 3.6 million square miles, which is similar in size to Canada, and can thrive in challenging environments.  The widespread presence and hardiness of mosses is why they can have such a significant impact on soil biodiversity and carbon sequestration. 

The research team hopes future work will focus on understanding the role of all types of vegetation, not just mosses and trees, in capturing carbon.

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Study: Modest moss supports billions of tons of carbon storage

Photo, posted August 23, 2017, courtesy of Peter Handke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Here Come The Lanternflies | Earth Wise

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The spotted lanternfly is an invasive pest from Asia that primarily feeds on tree of heaven, which is itself an invasive species that has become widespread.  The real problem is that the lanternfly can also feed on some 70 other plants such as grapevines, maples, fruit trees, and more.

The lanternfly was first discovered in the US in Pennsylvania in 2014 and has since spread to 14 states including New York, Massachusetts, Connecticut, and Rhode Island.  (It was first spotted in New York in Staten Island in 2020 and has continued to spread).

The insect poses a significant threat to New York’s agricultural and forest health. Both the adults and nymphs feed on the sap of plants which stresses them making them vulnerable to diseases and other insect attacks.  They also secrete a sticky substance that attracts molds and interferes with photosynthesis.

Lanternflies are not strong fliers.  They mostly spread through human activity by laying their eggs on vehicles, firewood, outdoor furniture, and other objects that people transport.

The bout of unusually warm weather that the Northeast experienced in early spring is likely to have jumpstarted the spotted lanternfly timeline and hatching could be bumped up to as early as May.

Agriculture officials are asking for people to look for spotted lanternfly egg masses and scrape them off with implements with a sharp edge.  Adult insects should be reported to local authorities and should be killed if at all possible.  There is lots of information online about how to recognize the egg masses and the insects.  Spotted lanternflies are not a direct threat to humans, but they have the potential to cause great harm to vineyards, orchards, and forests.

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Spotted Lanternfly

Photo, posted September 12, 2018, courtesy of the U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic From Sunlight | Earth Wise

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Photosynthesis is the process that plants use to turn water, carbon dioxide, and energy from sunlight into plant biomass.  It provides humans and much of animal life with food.  Photosynthesis is also nature’s way of reducing the amount of carbon dioxide in the atmosphere.  The CO2 is not directly stored in plants but rather is combined into organic compounds.

Researchers across the globe are trying to find effective ways to mimic photosynthesis.  One version of artificial photosynthesis seeks to take carbon dioxide and combine it into organic compounds that can be used as raw materials for various kinds of manufacturing. 

A research team in Japan has found a way to synthesize fumaric acid from carbon dioxide using sunlight to power the process.  Fumaric acid is a chemical typically synthesized from petroleum and is used as a raw material for making biodegradable plastics such as polybutylene succinate. 

Much of artificial photosynthesis research is aimed at using solar energy to convert carbon dioxide directly into a fuel rather than a raw material.  Such solar fuels can be produced by a variety of means including thermochemical (using the sun’s heat to drive chemical reactions), photochemical (using the sun’s light to drive chemical reactions), and electrochemical (using solar-generated electricity to drive chemical reactions.)   These approaches generally involve the use of specialized catalysts to drive the desired chemical reactions. 

One way or another, what techniques for artificial photosynthesis have in common is trying to imitate what plant life on Earth has been doing for millions of years. 

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Artificial photosynthesis uses sunlight to make biodegradable plastic

Photo, posted June 14, 2017, courtesy of Alex Holyake via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

City Greenery And Carbon Emissions | Earth Wise

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According to the United Nations, more than half of the world’s population currently lives in cities.  Projections show that the combination of urbanization and global population growth could add another 2.5 billion people to cities by 2050. 

Unsurprisingly, cities are a major contributor to climate change.  According to U.N. estimates, cities are responsible for 75% of global carbon dioxide emissions, with transportation and buildings being among the largest contributors. 

According to a new study of vegetation across New York City and some adjoining urban areas, photosynthesis by trees and grasses on many summer days absorbs all the carbon emissions produced by cars, trucks and buses, and then some.  In fact, on many summer days, the total carbon uptake in the region equaled up to 40% of a summer afternoon’s total emissions from all sources in the City. The results, which were recently published in the journal Environmental Research Letters, further highlights the critical importance of urban greenery.

Most previous studies have analyzed the carbon uptake of vegetation by looking at the contiguous tracts of green spaces, but this only comprises about 10% of metro areas.  Using detailed aerial radar imagery of New York City that mapped vegetation in unprecedented 6-inch grids, the researchers were able to include the other 90% of the metro area typically left out in most models. 

Since carbon uptake by vegetation only occurs during the growing season, green spaces in cities situated in warmer climates likely play a larger role in carbon uptake. 

As city populations swell around the world, every bit of urban greenery is critical in the fight against climate change. 

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New York City’s greenery absorbs a surprising amount of its carbon emissions

68% of the world population projected to live in urban areas by 2050, says UN

Photo, posted October 5, 2009, courtesy of David Orban via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Trees Are Growing Bigger | Earth Wise

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The alarming rate of carbon dioxide flowing into the atmosphere is having a real and actually positive effect on plant life. Higher concentrations of carbon dioxide make plants more productive because photosynthesis makes use of the sun’s energy to synthesize sugar out of carbon dioxide and water.  Plants make use of the sugar both as a source of energy and as the basic building block for growth.  When carbon dioxide levels go up, plants can take it up faster, supercharging the rate of photosynthesis.

In a new study published in the journal Nature Communications, scientists at Ohio State University found that trees are feasting on decades of carbon dioxide emissions and are growing bigger as a result. 

The researchers tracked wood volume in 10 different tree groups from 1997 to 2017 and found that all of them except aspens and birches grew larger.  Over that time period, carbon dioxide levels climbed from 363 parts per million to 405 parts per million.  According to the study, each 1% increase in lifetime CO2 exposure for trees has led to more than a 1% increase in wood volume.

In the big picture, the news isn’t so positive.  The global warming caused by increasing carbon dioxide levels increasingly threatens the forests of the world.  It has led to worsening droughts, insect infestations, and wildfires.  So overall, increasing levels of carbon dioxide are by no means a good thing for the world’s trees.  However, since trees are growing bigger more quickly, it means that planting them is an increasingly cost-effective method for fighting climate change because the same number of trees can sequester more carbon.

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As Carbon Dioxide Grows More Abundant, Trees Are Growing Bigger, Study Finds

Photo, posted September 12, 2015, courtesy of Nicholas A. Tonelli via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Progress On Artificial Photosynthesis | Earth Wise

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Photosynthesis is the process by which plants use the energy from sunlight to turn water and carbon dioxide into biomass and ultimately the foods we and other organisms eat.  Scientists at the University of California Riverside and the University of Delaware have found a way to create food from water and carbon dioxide without using biological photosynthesis and without needing sunlight.

The research, recently published in the journal Nature Food, uses a two-step electrocatalytic process to convert carbon dioxide, electricity, and water into acetate, which is the primary component of vinegar.   Food-producing microorganisms then consume the acetate in order to grow.   Solar panels are used to generate the electricity to power the electrocatalysis.  The result is a hybrid organic-inorganic system that is far more efficient in converting sunlight into food than biological photosynthesis.

The research showed that a wide range of food-producing organisms can be grown in the dark directly on the acetate output of the electrolyzer.  These include green algae, yeast, and the fungal mycelium that produce mushrooms.   Producing algae with this technology is about 4 times more energy efficient than growing it with photosynthesis.  Yeast production is about 18 times more energy efficient than the typical method of cultivating it using sugar extracted from corn.

Artificial photosynthesis has the potential to liberate agriculture from its complete dependence on the sun, opening the door to a wide range of possibilities for growing food under the increasingly difficult conditions imposed by the changing climate.

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Artificial photosynthesis can produce food without sunshine

Photo, posted September 7, 2016, courtesy of Kevin Doncaster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Better Way To Recycle Plastic | Earth Wise

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The current state of plastic recycling is not very effective.  Plastic recycling is only able to replace 15-20% of the fossil-fuel-derived raw material needed to produce society’s demand for plastic.

Researchers at Chalmers University in Sweden have now demonstrated how the carbon content in mixed waste could be used to replace all of the fossil raw materials in the production of new plastic.  In principle, their technology could completely eliminate the climate impact of plastic materials.

According to the researchers, there are enough carbon atoms in waste to meet the needs of all global plastic production.

The Chalmers process is based on thermochemical technology and involves heating waste to 1100-1500 degrees Fahrenheit.  The waste is thereby vaporized and when hydrogen is added, becomes a carbon-based substance that can replace the fossil-fuel building blocks of plastic.  The method does not require sorting the waste materials.  Different types of waste, such as old plastic products and even paper cups, with or without food residues, can be fed into the recycling reactors.  The researchers are now developing the techniques required to utilize their recycling technology in the same factories in which plastic products are currently being made from fossil oil or gas.

The principle of the process is inspired by the natural carbon cycle in which plants break down into carbon dioxide when they wither and die, and then photosynthesis uses carbon dioxide and solar energy to grow new plants.

Producing new plastics would no longer require petroleum or other fossil fuels as raw materials.  If the energy needed to drive the recycling reactors is taken from renewable sources, plastics could become the basis of a sustainable and circular economy.

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Pioneering recycling turns mixed waste into premium plastics with no climate impact

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Less Phytoplankton In The Gulf Of Maine | Earth Wise

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Phytoplankton, also known as microalgae, are the base of the marine food web and also play a key role in removing carbon dioxide from the air.  They are eaten by primary consumers like zooplankton, small fish, and crustaceans. 

Phytoplankton, like land plants, absorb carbon dioxide from the atmosphere and use photosynthesis to grow.  Then they become a food source for other organisms and ultimately for people who depend upon marine ecosystems.   If phytoplankton productivity is disrupted, there can be adverse effects on regional fisheries and the communities that depend on them.

The Gulf of Maine is becoming warmer and saltier, because of ocean currents pushing warm water into the gulf from the Northwest Atlantic.  These temperature and salinity changes have led to a significant decrease in the productivity of phytoplankton.   According to a new paper from scientists at Bigelow Laboratory of Ocean Sciences in Maine, phytoplankton are about 65% less productive in the gulf than they were 20 years ago.

The study’s results come from the analysis of the Gulf of Maine North Atlantic Time Series, a 23-year sampling program of the temperature, salinity, chemical, biological, and optical measurements of the gulf.  The scientists refer to what they describe as a giant windmill effect happening in the North Atlantic, which is changing the circulation of water coming into the Gulf of Maine.  In the past, inflows from the North Atlantic brought water from the Labrador Current, which made the gulf cooler and fresher.  The new circulation is making the water warmer and saltier.

These changes have significant implications for higher marine species, fisheries, the lobster industry, and other activities in the states that border the Gulf of Maine.

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NASA-funded Study: Gulf of Maine’s Phytoplankton Productivity Down 65%

Photo, posted November 15, 2015, courtesy of Paul VanDerWerf via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Removing Carbon With The Oceans | Earth Wise

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There is increasing concern that reducing carbon emissions alone will not be sufficient to stabilize the climate and that technologies that actively remove carbon dioxide from the air will be needed.  There has been a fair amount of analysis of the efficacy of storing carbon in agricultural soil and in forests, but there has not been comparable studies of the risks, benefits, and trade-offs of ocean-based strategies. 

The oceans currently absorb about a quarter of the world’s carbon dioxide emissions.  There are multiple ways in which oceans could be induced to store much more.  A new report from the National Academies of Sciences, Engineering, and Medicine looks at several ocean carbon dioxide removal strategies in terms of efficacy, potential costs, and potential environmental risks.

One approach involves adding nutrients to the ocean surface to increase photosynthesis by phytoplankton.  The approach has a medium to high chance of being effective and has medium environmental risks.

Another approach is large-scale seaweed farming that transports carbon to the deep ocean or into sediments.   It has medium efficacy chances but higher environmental risks.

Protection and restoration of coastal ecosystems including marine wildlife would have the lowest environmental risk but only low to medium efficacy.

Chemically altering ocean water to increase its alkalinity in order to enhance reactions that take up carbon dioxide would be highly effective but a medium environmental risk.

The report describes some other approaches as well.  It recommends a $125 million research program to better understand the technological challenges as well as the potential economic, social, and environmental impacts of increasing the oceans’ absorption of carbon dioxide.

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Oceans Could Be Harnessed to Remove Carbon From Air, Say U.S. Science Leaders

Photo, posted August 21, 2016, courtesy of Quinn Dombrowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildfires And Algal Blooms

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Australia is no stranger to wildfires. But the 2019-2020 season proved to be particularly severe: wildfires destroyed 3,100 homes, displaced 65,000 people, and burned more than 72,000 square miles – roughly the same size as Washington State. The season is colloquially referred to as the Black Summer.

According to a new study recently published in the journal Nature, clouds of smoke and ash from these wildfires triggered widespread algal blooms thousands of miles downwind to the east in the Southern Ocean.

The study, which was led by researchers from Duke University, shows that aerosol particles in the smoke and ash fertilized the water as they fell into it.  This provided the nutrients that fueled unprecedented blooms in that region, conclusively linking for the first time a large-scale response in marine life to fertilization by pyrogenic iron aerosols from a wildfire.

This finding raises questions about the role wildfires may play in the growth of phytoplankton, the microscopic marine algae that – through photosynthesis – absorbs large amounts of climate-warming carbon dioxide from Earth’s atmosphere. 

According to the research team, the Australian algal blooms were so extensive that the subsequent increase in photosynthesis may have temporarily offset a substantial portion of the wildfires’ CO2 emissions.  It remains to be seen how much of the absorbed CO2 remains safely stored in the ocean and how much it has been released back into the atmosphere. 

The researchers plan to investigate the fate of the phytoplankton further.  They also plan more research to better predict where and when aerosol deposition will boost phytoplankton growth in the future.  

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Australian wildfires triggered massive algal blooms in Southern Ocean

Photo, posted January 12, 2020, courtesy of BLM-Idaho via Flickr.

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