harvest

Fuel from Corn Waste

June 27, 2025 By EarthWise Leave a Comment

A substantial amount of corn is grown in this country for the purpose of producing ethanol. The value of doing so is debatable for many reasons. Nevertheless, the majority of the corn crop is grown for food. But along with all that corn, there is corn stover. Stover is the dried stalks, leaves, and other plant parts that remain in the field after the corn itself has been harvested. Corn stover is the largest quantity of biomass residue in the United States. Around 250 million tons of it is produced annually and the majority of it is left unused. Some is used for animal feed and other purposes and has monetary value, but much of it goes to waste.

Scientists at Washington State University have developed a way to produce low-cost sugar from stover that can be used to make biofuels and other bioproducts.

Corn stover is an abundant and cheap source of biomass, which holds great potential as a source of energy and valuable chemicals. The challenge is to overcome the high cost of processing stover whose complex structural molecules like cellulose and lignin need to be broken down.

The new process uses potassium hydroxide and ammonium sulfite to convert stover into a sugar. It is a mild-temperature process that allows enzymes to break down the cellulosic polymers in stover into sugar, which can then be fermented into biofuels. The resulting sugar from the process would be cost-competitive with low-cost imported sugars. The researchers estimate that their patent-pending process could produce sugar that could be sold for as low as 28 cents per pound.

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Scientists discover a new way to convert corn waste into low-cost sugar for biofuel

Photo, posted August 30, 2012, courtesy of Idaho National Laboratory Bioenergy Program via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mining with plants

February 21, 2025 By EarthWise Leave a Comment

Plants absorb nutrients and minerals from the soil as they grow and incorporate them into their leaves and stems. Such plants can be used to remove toxic elements from soil. Cleaning soil in this way is called phytoremediation.

Researchers at the University of Massachusetts Amherst are trying to go beyond phytoremediation and do phytomining, in which hyperaccumulated minerals from the soil can be harvested from plants for use in industrial or manufacturing applications.

One mineral that is critically needed for modern technology is nickel. There are trace amounts of nickel in nearly one million acres of topsoil in the US, making the soil inhospitable for most crops, but the economics and environmental impact of extracting it make doing it impractical.

A common plant, Alyssum murale, is a nickel hyperaccumulator; in fact, up to 3% of the plant’s biomass can be made up of nickel. But the plant is slow-growing and difficult to manage and is also considered an invasive species

Another common plant, Camelina sativa, does not have the downsides associated with Alyssum and is also a rich source of valuable biofuel. The Amherst researchers are working to determine which genes and proteins are responsible for Alyssum’s nickel hyperaccumulation and hope to genetically engineer Camelina sativa to have the same ability.

The researchers believe there is enough nickel in barren soil in the US to supply 50 years of phytomining. It wouldn’t supply all the nickel the economy needs, but it could account for 20 to 30 percent of the projected demand.

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Scientists at UMass Amherst Engineer Plant-based Method of ‘Precious’ Mineral Mining

Photo, posted July 10, 2017, courtesy of Matt Lavin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind farms and sea farms

August 5, 2024 By EarthWise Leave a Comment

There has been increasing use of agriculture coexisting with solar farms. This dual use of land is a win-win situation. Recently, Danish researchers have been investigating the potential for farming marine products at offshore wind farms.

Scandinavia’s largest wind farm, Kriegers Flak, is the site of a four-year-old project in which long lines are stretched between the wind farm’s pylons and are used to grow mussels and seaweed. With the first harvest that has taken place after 18 months, it is showing signs of early success.

Seaweed and mussels are low trophic aquaculture crops. That means that that they don’t need to be fed or fertilized. They take up nutrients from the sea and produce healthy foods.

The 328-foot lines spread between the turbines can be used to grow substantial quantities of the underwater seafood. According to modeling by Aarhus University – the institution conducting the study – using just a tenth of Denmark’s wind park area could produce tons of seafood annually while using only the naturally-available resources. This form of aquaculture captures emissions instead of producing them.

Researchers say that it is time to develop guidelines to encourage companies to plan for multiple uses of the ocean because countries are ramping up production of clean energy from offshore wind farms. Denmark was the first country in the world to install a commercial offshore wind park in 1991. Over 30 years later, nearly half of the country’s electricity comes from wind turbines.

The benefits of such sea farms combined with offshore wind farms go beyond food production and clean energy production. They also help improve water quality and capture carbon. It is another win-win situation.

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Beneath offshore wind turbines, researchers grow seafood and seaweed

Photo, posted August 5, 2007, courtesy of Andreas Klinke Johannsen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Dark chocolate is not so dangerous

July 15, 2024 By EarthWise Leave a Comment

Last year, Consumer Reports published a story stating that a third of chocolate products contain potentially dangerous amounts of heavy metals, in particular lead and cadmium. Since it contains much more cacao, dark chocolate was singled out as the most worrisome product. Needless to say, chocolate lovers found this report quite alarming.

A new study by Tulane University published in Food Research International employed a larger sample size, expanded the scope of testing to 16 metals, and included a risk assessment of toxic metals as well as accounted for the nutritional contribution of essential minerals.

The conclusions of the study were that dark chocolate poses no adverse risk for adults and contains nutritionally beneficial levels of essential minerals. Some risks remain for very young children, but only from a very small number of chocolate products and only when large quantities are consumed.

The study sampled 155 dark and milk chocolates from various global brands sold in the United States. It modeled the risk of eating one ounce of the chocolate per day or two large whole bars a week.

Only one brand exceeded the international limit for cadmium; four had cadmium levels that could pose a risk for a child weighing less than 33 pounds. Only two bars contained lead levels above California interim standard, but neither posed adverse risks for anyone.

Lead in chocolate comes from post-harvest processing; cadmium comes from the soil. South American chocolates generally have higher levels of metals than chocolates from Asia and West Africa. Most dark chocolate in the U.S. is sourced from West Africa.

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A dark side to dark chocolate? New study finds very minimal risk for kids from metals in chocolates

Photo, posted February 19, 2012, courtesy of Bodo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Car tires in your salad

June 26, 2024 By EarthWise Leave a Comment

There seems to be no end to the types of pollution we have introduced into the environment. One that has only recently started to gain attention is pollution caused by vehicle tires.

Through normal wear and tear, as vehicles drive along roadways, their tires cast off countless bits of rubber. These particles can linger in the atmosphere or can be washed down sewage drains and into waterways. In the water, these particles leach compounds that are toxic to wildlife.

Tires contain various chemical additives that prevent them from cracking and degrading along with various metals and other materials added to rubber and artificial rubber. Some of these additives are acutely toxic or even carcinogenic.

A recent study by researchers at the University of Vienna tested leafy vegetables that were grown in Switzerland, Spain, and Italy, and were sold in Swiss supermarkets. The study also tested vegetables harvested directly from Israeli farmlands.

Tire ingredients were found in 11 out of 15 samples gathered from Swiss supermarkets and 9 out of 13 samples collected from Israeli fields. Among these are 6PPD, a tire additive that has been identified as the cause of the extensive deaths of coho salmon on the US West Coast.

The researchers say that farmers may be introducing tire additives by irrigating crops with treated wastewater or by using sewage sludge as fertilizer. Airborne tire particles may also be settling on farm soil.

The concentration of tire particles found in the leafy vegetables are relatively low, but it is troubling that we are eating dangerous chemicals used to improve the quality of tires.

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Leafy Vegetables Found to Contain Tire Additives

Photo, posted October 14, 2014, courtesy of Green Mountain Girls Farm via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hybrid beef rice

March 19, 2024 By EarthWise Leave a Comment

There is growing interest in innovative and more environmentally friendly ways to provide protein in our diets. We’ve heard a great deal about lab-grown or cultured meats and about protein derived from insects. Whether either of these things achieves mainstream acceptance remains to be seen.

Scientists at Yonsei University in South Korea have developed a method for creating cultured beef rice – truly a hybrid food. The method, described in the journal Matter, results in a nutritious and flavorful food that could be more affordable and have a smaller carbon footprint than current protein sources.

The researchers took rice grains – which are porous and have organized structures – and seeded them with beef muscle and stem cells and allowed them to culture for 9 to 11 days. The harvested final product is a cell-cultured beef rice.

The hybrid beef rice was steamed and subjected to various food industry analyses, including nutritional value, odor, and texture. The hybrid rice has 8% more protein and 7% more fat than regular rice. It was somewhat firmer and more brittle than ordinary rice. Hybrid rice with higher muscle content had beef- and almond-related odor compounds, while those with higher fat content had compounds corresponding to cream, butter, and coconut oil.

The hybrid rice has low food safety risks and a relatively easy production process. If commercialized, the hybrid rice would be far less expensive than beef. The researchers are optimistic that it can be commercialized. They are continuing to work on the processing, hoping to further boost the nutritional value. Like other unconventional foods under development, the biggest question is ultimately whether people will want to eat it.

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By growing animal cells in rice grains, scientists dish up hybrid food

Photo, posted January 26, 2010, courtesy of CIAT / Neil Palmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Protecting wine grapes from wildfire smoke

February 27, 2024 By EarthWise Leave a Comment

In recent years, wildfires have become a major threat to the wine industry because of the effects of smoke on wine grapes. Smoke taint from the California fires of September 2020 significantly impacted the quality of wine grapes. In total, smoke taint cost the wine industry in Western states more than $3 billion in losses from the hundreds of thousands of tons of wine grapes that could not be harvested because of the off flavors imparted by the smoke. The California wine industry alone is a $43 billion a year business and the state’s frequent wildfires are a major threat to it.

Researchers at Oregon State University have developed techniques for eliminating the effects of three volatile chemical compounds that contribute to smoke taint in grapes. The compounds are guaicol, syringol, and meta-cresol.

The researchers developed cellulose nanofiber-based coatings that can be applied to grapes in the vineyard. The coatings can block guaicol and syringol and capture meta-cresol.

Blocking is ideal because the coating doesn’t absorb the wildfire smoke compounds. Therefore, it doesn’t have to be washed off. Capturing means the coating absorbs the compounds and would need to be washed off. Ideally, a coating that doesn’t need to be washed off would save time, money, and water.

Two years of studies at Oregon State found that the coatings do not impact the growth and quality of wine grapes. In an era when wildfires are increasingly common and extensive, growers need something they can spray on their vines to protect their grapes. If the Oregon State technology can be commercialized, it would be a game-changer for the Western U.S. wine industry.

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Spray coating for grapes shows promise in battle between wildfire smoke and wine

Photo, posted October 3, 2006, courtesy of Naotake Murayama via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Restoring Biocrusts | Earth Wise

June 8, 2023 By EarthWise Leave a Comment

Biocrusts are complex ecosystems that form a thin layer on the surface of soils in arid and semiarid environments. They are composed of variety of microbes including cyanobacteria, green algae, fungi, lichens, and mosses. Biocrusts play a crucial role in maintaining soil health and ecosystem sustainability.

Biocrusts are under assault from human activities including agriculture, urbanization, and off-road vehicle use. Climate change is also placing stress on biocrusts, which are struggling to adapt to increasing temperatures.

Researchers at Arizona State University have proposed a novel approach to restoring healthy biocrusts. Their idea is to make use of solar energy farms as nurseries for generating fresh biocrust. The arrays of solar panels serve as shields from excessive heat and allow biocrusts to flourish and develop. The newly generated biocrusts can then be used to replenish arid lands where the existing biocrusts have been damaged or destroyed.

When such biocrusts are harvested, the natural recovery process is rather slow, taking around six or eight years to fully recuperate. But the researchers found that when harvested areas are reinoculated with the microbes, the biocrust cover can reach near-original levels within a year.

The ASU researchers demonstrated the viability of the approach in a three-year study at a solar farm in Arizona’s lower Sonoran Desert. Based on their results, they conclude that the use of large solar farms for this purpose could provide a low-cost, low-impact, and high-capacity method to regenerate biocrusts and enable soil restoration on a regional scale. They have dubbed their new approach as “crustivoltaics.”

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Using solar farms to generate fresh desert soil crust

Photo, posted March 12, 2023, courtesy of Eric Peterson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Perennial Rice | Earth Wise

December 9, 2022 By EarthWise Leave a Comment

People have been cultivating rice for more than 9,000 years. Cultivated rice is an annual crop which is often extended to two crops a year by a process called ratooning, which is cutting back annual rice to obtain a second, weaker harvest.

An extensive project involving multiple institutions in China, the U.S., and Australia has been developing perennial rice. The researchers developed it through hybridization, crossing a type of Asian domesticated annual rice with a wild perennial rice from Africa. Using modern genetic tools to identify candidate plants, the team identified a promising hybrid in 2007, planted large-scale field experiments in 2016, and released the first commercial perennial rice variety, called PR23, in 2018.

The researchers spent five years studying the performance of the perennial rice alongside annual rice on farms in China’s Yunnan Province. For the most part, the yield of the perennial rice was equivalent to that of annual rice over a period of four years.

Because farmers don’t have to plant rice each season, growing perennial rice requires almost 60% less labor and saves nearly half the costs of seed, fertilizer, and other inputs.

Perennial rice is already changing the lives of more than 55,000 smallholder farmers in southern China and Uganda. The economic benefits vary by location, but overall profit increases ranged from 17% to 161% over annual rice.

There are already three perennial rice varieties available to farmers, but researchers aren’t done refining the crop. They plan to use their methodology to enhance traits such as aroma, disease resistance, and drought tolerance to newer versions.

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Farmers in China, Uganda move to high-yielding, cost-saving perennial rice

Photo, posted February 25, 2002, courtesy of Matthieu Lelievre via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And Crabs | Earth Wise

November 8, 2022 By EarthWise Leave a Comment

Globally, there are more than 6,000 species of crabs. In Alaska’s waters alone, there are 18 species, including 10 that are commercially fished. The perils of crab fishing in this region, including freezing temperatures, turbulent seas, and raising full pots that can weigh well over a ton, have been highlighted for many years in the reality TV series Deadliest Catch.

One of those commercially-fished species is the Alaska snow crab. Alaska snow crabs are a cold-water species found off the coast of Alaska in the Bering, Beaufort, and Chukchi Seas.

In October, officials in Alaska announced that the upcoming winter snow crab season would be canceled for the first time ever due to a sharp population decline. While the number of juvenile snow crabs was at record highs just a few years ago, approximately 90% of snow crabs mysteriously disappeared ahead of last season. Officials also canceled the Bristol Bay red king crab harvest for similar reasons for the second year in a row.

The closures dealt a severe blow to crab fishers in the region. According to the Alaska Seafood Marketing Institute, Alaska’s crab fishing industry is worth more than $200 million.

The canceled seasons also raise questions about the role of climate change in the snow crab population crash. While the causes of the decline are still being researched, scientists suspect that warmer temperatures are responsible. Temperatures in the Arctic region have warmed four times faster than the rest of the planet.

As the climate continues to change, the warming waters around Alaska may become increasingly inhospitable to snow crabs and other species.

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Alaska’s Bering snow crab, king crab seasons canceled

Alaska cancels snow crab season for first time after population collapses

Photo, posted November 16, 2010, courtesy of David Csepp / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Turning Atmospheric Carbon Into Useful Materials | Earth Wise

July 7, 2021 By EarthWise Leave a Comment

Plants have the ability to capture carbon dioxide from the atmosphere and incorporate it into leaves, fruits, wood, and other plant materials. This beneficial process is mostly temporary, as much of this carbon dioxide from plant matter ends up back in the atmosphere through decomposition, or even burning.

Researchers at the Salk Institute have proposed a more permanent fate for captured carbon by turning plant matter into a valuable industrial material called silicon carbide.

In a recent study published in the journal RSC Advances, Salk scientists transformed tobacco and corn husks into silicon carbide and evaluated and quantified the benefits of the process.

The researchers used a previously reported method to transform plant matter into silicon carbide in three stages and carefully tracked the carbon utilization at each stage.

Stage one is growing the plants. They used tobacco from seed, chosen for its short growing season. Then the harvested plants are frozen, ground into a powder, and treated with chemicals including a silicon-containing compound. Finally, the powder is subjected to a high-temperature process resulting in the production of silicon carbide.

Their analysis showed that much of the carbon sequestered by growing the plants could be preserved through the full process and the amount of energy required for the production of the silicon carbide (mostly from the high-temperature process) is comparable to current manufacturing processes for the material.

Permanently sequestering carbon from agricultural waste products by incorporating it into a valuable industrial material would be a valuable addition to strategies for reducing greenhouse gases in the atmosphere.

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Transforming Atmospheric Carbon Into Industrially Useful Materials

Photo, posted August 3, 2013, courtesy of AJ Garrison via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Harvesting Water From Air | Earth Wise

May 17, 2021 By EarthWise Leave a Comment

Developing new technologies that harvest water from the air is a growing field of research driven by the fact that more and more people live in areas where fresh water is in short supply. Estimates are that roughly half the world’s population lives in regions with severe freshwater shortages for at least one month each year.

We have previously discussed some of the novel approaches that researchers are taking to enhance water harvesting. The work at UC Berkeley using metalorganic frameworks is a notable example.

One of the key problems in harvesting water from air is that many droplets that condense from water vapor in the air are too small to be collected and when they cover a surface, they can actually impede further condensation.

University of Texas at Dallas researchers have developed a novel surface that encourages tiny water droplets to move spontaneously into larger droplets. The droplets actually self-climb along an oil, ramp-shaped meniscus. The meniscus acts like a bridge along which microdroplets spontaneously climb upward and coalesce with larger water droplets. They call this the coarsening droplet phenomenon. It is enabled by a liquid lubricant with a unique hydrophilic nature. They actually discovered the lubricant’s special properties by accident when in a lubricant test they observed smaller water droplets propel themselves into larger droplets.

Based on experimental data, the coarsening surface enhances the water harvesting rate 200% higher than other techniques. The team continues to work on ways to use the new lubricant to make sustainable water harvesting systems that are mobile, smaller in size, lower in weight, and less expensive. If they are successful, they will essentially be able to harvest water anywhere that has air.

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New Physical Phenomenon Aids Harvest of Water from Air

Photo, posted April 26, 2014, courtesy of Toukou Sousui via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Lockdown Cleans Up Indian Air | Earth Wise

May 13, 2020 By EarthWise Leave a Comment

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

India suffers from some of the worst air pollution in the world. Of the most polluted cities in the world, 21 out of 30 were in India in 2019. According to World Health Organization standards, at least 140 million people in India breathe air containing 10 times or more greater levels than the safe limit for pollutants. Air pollution contributes to the premature death of 2 million Indians every year.

Half of India’s air pollution comes from industry, 27% from vehicles, and 17% from crop burning. Crop burning is prevalent because it is much cheaper than mechanical tilling after the harvest.

On March 25, the Indian government placed its 1.3 billion citizens under a strict lockdown to reduce the spread of COVID-19. The country-wide mandate decreased activity at factories and drastically reduced car, bus, truck, and airplane traffic.

Within one week, NASA satellite sensor observed aerosol levels at a 20-year low for this time of year in northern India. Aerosols are tiny solid and liquid particles suspended in the air that reduce visibility and can damage the human lungs and heart. Some aerosols have natural sources, such as dust storms, volcanic eruptions, and forest fires. But many come from human activities such as the burning of fossil fuels and croplands. Scientists expected to see changes in atmospheric conditions during the Indian lockdown, but the current changes are dramatic. They also present a unique opportunity to separate how natural and human sources of aerosols affect the atmosphere.

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Airborne Particle Levels Plummet in Northern India

Photo, posted April 29, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metal From Plants | Earth Wise

March 31, 2020 By EarthWise 2 Comments

Large amounts of metal in soil are generally bad for plants. But there are about 700 species of plants that thrive in metal-rich soils. These plants don’t just tolerate minerals from soil in their bodies but actually seem to hoard them to ridiculous levels.

In areas where soils are naturally rich in nickel, typically in the tropics and Mediterranean basin, plants have either died off or have adapted to become nickel loving. Slicing open a tree with this adaptation produces a neon blue-green sap that is actually one-quarter nickel, which is far more concentrated than the ore that typically feeds commercial nickel smelters.

A group of researchers from the University of Melbourne and other institutions is investigating whether this phenomenon is not just interesting but might also be of real commercial value. They established a plot of land in a rural village in Borneo and have been harvesting growth from nickel-hyper accumulating plants. Every six to twelve months, a farmer shaves off one foot of growth from these plants and either burns or squeezes the metal out. After a short purification, they end up with about 500 pounds of nickel citrate, potentially worth thousands of dollars on international markets.

Phytomining – extracting minerals from hyper-accumulating plants – cannot fully replace traditional mining techniques. But the technology could enable areas with toxic soils to be made productive and might allow mining companies to use plants to clean up their former mines and waste while actually collecting some revenue.

There are other plants that suck up cobalt, zinc, and similarly crucial metals. With growing demand for metals, perhaps it is time to harvest them on the farm.

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Down on the Farm That Harvests Metal From Plants

Photo courtesy of the University of Queensland.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Canola Crops From Frost

November 20, 2019 By EarthWise Leave a Comment

Canola is one of Canada’s most valuable crops. In fact, Canada is the world’s largest exporter of canola oil. The international market for canola oil is $27 billion a year. The oil is very popular because it has a relatively low amount of saturated fat, a substantial amount of monosaturated fat, and is very neutral tasting.

Canadian canola farmers worry a great deal about late season, non-lethal frosts because the frosts prevent chlorophyll – a photosynthetic pigment in the seeds – from breaking down, a process they call “degreening”. The farmers seek to have high-quality yellow embryos at seed maturity. When the harvest contains more than 2% of green seeds, it can no longer produce Grade No. 1 quality oil. When green seeds are processed to extract canola oil, the chlorophyll in the seeds reduces the oil’s storability and quality. As a result, farmers receive a lower price for frost-damaged green seed canola. This costs Canadian farmers and estimated $150 million annually.

Researchers at the University of Calgary have developed gene-based technology to produce canola plants that can withstand late-season frost and still produce high-quality seed. They identified a specific protein that controls chlorophyll breakdown and seed maturity. Genetic manipulation is able to enhance the seed degreening system. They were able to reduce the amount of chlorophyll in the genetically modified canola lines by 60% after the plants were exposed to non-lethal frost.

Ultimately, the researchers plan to develop a method to incorporate the modification into canola hybrid lines in such a way that it will be readily accepted by consumers concerned about genetically modified organisms.

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New technology helps protect valuable canola crops from frost

Photo, posted August 29, 2018, courtesy of Tinker and Rove via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Pulling Water From The Air

October 14, 2019 By EarthWise Leave a Comment

A couple of years ago, we reported on the early development of a device that harvests water from the air that even works in the low humidity environment of a desert. Since then, the researchers from UC Berkeley have continued to improve the device and it is now 10 times better than it was two years ago.

The harvester is based on a porous water-absorbing material called a metal-organic framework, or MOF. The latest version can pull more than five cups of water from low-humidity air per day for every kilogram of the improved MOF material and that is more than enough water to sustain a person. The harvester cycles around the clock and is powered by solar panels and a battery.

Previous techniques for condensing water from air at low humidity required cooling down the air to temperatures below freezing, which is not economically practical. The MOF-based device does not require any cooling.

The Berkeley researchers have formed a startup company – Water Harvester, Inc. – which is now testing and will soon market a device the size of a microwave oven that can supply 7 to 10 liters of water per day, which is enough drinking and cooking water for two or three adults.

An even larger version of the harvester, which would be the size of a small refrigerator, would provide 200 to 250 liters of water per day, enough for a household to drink, cook, and shower. The new company envisions a village-scale harvester that would produce 20,000 liters per day, still running off of solar panels and a battery.

Water Harvester believes the water needs for many people can come out of the thin air.

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Water harvester makes it easy to quench your thirst in the desert

Photo courtesy of Grant Glover (University of South Alabama) via UC Berkeley.

Earth Wise is a production of WAMC Northeast Public Radio.

Mexico’s Wonder Plant

September 13, 2019 By EarthWise Leave a Comment

In 1979, an American naturalist named Thomas Hallberg visiting a small town in Oaxaca, Mexico was amazed to find a type of local maize – or corn – that grew nearly 20 feet high in poor-quality soil even though the local farmers did not use any fertilizer.

The unique corn plant had aerial roots that grew a mucous-like gel just before harvest season. It seemed totally implausible, but the plant seemed to be fixing its own nitrogen: extracting it from the air and somehow making it useful to the plant.

In 1992, Hallberg returned with a group of Mexican scientists and collected samples to study in his lab. His research showed that the maize indeed received nitrogen from the air through its aerial roots. It took over 20 years to figure out what was going on in the plants. It turns out that bacteria that thrive in the low-oxygen environment of the maize’s mucus pulls nitrogen from the air and feeds it to the plant.

Scientists will probably spend years figuring out if a commercial application of this indigenous maize is viable. It isn’t guaranteed that the self-fertilizing trait of the plant can be bred into a commercial crop. But if it can, the payoff would be huge. Farmers spend more than $3 billion a year on corn fertilizer in the US alone.

A vexing problem is who should reap the financial benefits of the maize. The isolated village where the plant is grown has already signed an agreement to share in any such benefits. But there are other Oaxacan villages that also grow the plant.

Mexico’s wonder plant is likely to be caught up in the growing issue of biopiracy, which is the exploitation of indigenous knowledge and biological resources without permission.

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Indigenous Maize: Who Owns the Rights to Mexico’s ‘Wonder’ Plant?

Photo credit: ALLEN VAN DEYNZE/UC DAVIS

Earth Wise is a production of WAMC Northeast Public Radio.

Saved By The Trees

February 1, 2019 By EarthWise Leave a Comment

The island of Kokota, part of the Zanzibar Archipelago off the coast of Tanzania, is tiny – only one square kilometer and home to just 500 people. For centuries, its residents subsisted by harvesting the islet’s natural resources, including its trees.

By the early 21st century, the deforestation had become unsustainable and the islanders faced a crisis. Fisheries were depleted, and rivers ran dry. The changing climate brought rising sea levels, more erratic rainfall, and coral bleaching in the surrounding waters. The situation looked hopeless.

But in recent years, the island has come back from the brink of ruin. Reforestation efforts began in 2008 on the larger island of Pemba and on Kokota itself, led by a Pemba local and a Canadian tree planter who formed the non-profit Community Forests International. Since then, nearly 2 million trees have been planted on the two islands. Enthusiastic volunteers on Kokota usually help plant trees during the rainy season, when water is plentiful.

Community Forests International, along with spearheading the tree planting effort, also built Kokota’s first school, and installed rainwater storage tanks for the community.

The conservation group is now devising ways for Kokota to make more money by diversifying its agriculture with crops that grow well in its climate including spices like cloves, cinnamon, and nutmeg. They are also helping locals to grow more and different vegetables in their gardens.

Small, poor communities are often the most vulnerable to the effects of climate change, such as drought, powerful storms, and depleted fisheries. Tiny Kokota provides an example of an environmental comeback. Fighting climate change requires economic solutions along with environmental solutions. For this one tiny island, it appears to have been saved by the trees.

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