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Controlled Environment Agriculture | Earth Wise

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The term “controlled environment agriculture” (or CEA) refers to any number of systems embodying a technology-based approach to farming.  CEA can range from simple shade structures to greenhouses to full indoor or vertical farms.  At the most advanced level, CEA systems are fully automated, closed loop systems with controlled lighting, water, and ventilation.   Many systems make use of hydroponics rather than traditional soil.

The goal of CEA systems is to provide optimum growing conditions for crops and prevent disease and pest damage. 

A recent study by the University of Surrey in the UK sought to understand the impact of using CEA systems to grow lettuce, which is a high-value crop that is often grown in such systems.

The study found that, on average, CEA methods produce double the crop yields compared to field-based agriculture.  They also found that the cultivation time of CEA yields was, on average, 40 days.  This compares with an average cultivation time of 60-120 days for field-based agriculture.  More specifically, production of lettuce using CEA was 50% faster in the summer and up to 300% faster in the winter.

Climate change presents many difficult challenges to society, not the least of which is its threat to food security.  Controlled environment agriculture could allow cultivation of crops in harsh environments and in the face of changing climates.  Quantifying the benefits CEA can have on yield and growth provides important information for advancing our understanding of where and when this technology can bring the most value to society. 

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Using artificial methods for growing crops could help solve global food security

Photo, posted February 24, 2013, courtesy of Cindy Kurman / Kurman Photography via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Benefits Of No-Till Farming | Earth Wise

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No-till farming is not new.  In fact, it was used as far back as 10,000 years ago.  But during the 18th and 19th centuries, tilling became popular because it allowed farmers to plant seeds more efficiently.

Tilling (or ploughing) is the process of preparing the soil for the cultivation of seeds by overturning the soil.  The practice works animal manure, weeds, and other surface residues deep into the soil.  While this all sounds like a good thing, it’s not. 

Tilling removes plant matter and loosens the soil, leaving the soil bare and vulnerable to erosion.  Tilling also displaces the millions of microbes and insects that form healthy soil biology.  The long-term use of tilling can turn healthy soils into lifeless growing mediums dependent on chemical inputs.  

But no-till farming also tends to rely on chemical inputs like glyphosate for weed control.  According to a new study recently published in Agronomy Journal, researchers at Penn State have found that farmers using no-till farming can reduce herbicide use and still maintain crop yields by implementing integrated weed-management methods.   

The research team conducted a nine-year experiment using herbicide-reduction practices in a crop rotation, which included soybean, corn, alfalfa, and canola.  Some of the practices used to reduce herbicide inputs included seeding small-grain companion crops with perennials, and plowing once in six years to terminate the perennial forage rather than killing it with an herbicide. 

While there was more weed biomass in the reduced herbicide treatment, the researchers found that the added weed pressure did not substantially affect crop yields. 

It is possible to make agriculture more environmentally-friendly and sustainable without sacrificing productivity.

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No-till production farmers can cut herbicide use, control weeds, protect profits

Photo, posted February 11, 2019, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Pesticide From Beer | Earth Wise

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Researchers from the Neiker Basque Institute for Agricultural Research and Development in Spain have demonstrated that a combination of rapeseed cake and beer bagasse can be used to reduce populations of soil parasites and increase crop yields. 

Beer bagasse is spent brewers’ grain – the stuff that is left over after the beer is made.  Beer brewing generates substantial amounts of by-products, including large amounts of spent grain.  It already has some practical uses, including as a feedstock for biofuel, as a food additive, and it even has some medical uses.  But the new research has shown that the bagasse can be the basis for a biodisinfestation treatment to be used in agriculture.  The aim is to disinfect soils, protect soil microorganisms, and increase crop yields.

The actual material studied was a mixture of beer bagasse, rapeseed cake, and a generous amount of fresh cow manure.  The high nitrogen content of the mixture promotes the activity of beneficial microorganisms in the soil, which helps to break down organic matter and kill off nematodes and other parasites that damage crops.

Nematodes are common parasites that can penetrate plant roots to lay their eggs, which damages the root and prevents the plants from absorbing nutrients effectively.  Application of the bagasse-based mixture over 12 months increased crop yields by 15% and boosted healthy soil microbes.

The study demonstrated that agricultural byproducts can be an effective treatment for root-knot nematodes and other soil parasites, increase crop yields, and help promote sustainable food systems to reduce waste from the agricultural industry.  The researchers hope to identify other potential organic treatments for tackling soil parasite problems.

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Beer byproduct mixed with manure proves an excellent organic pesticide

Photo, posted July 1, 2011, courtesy of Quinn Dombrowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Energy And Agriculture | Earth Wise

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According to a new study by Oregon State University researchers, co-developing land for both solar voltaic power and agriculture could provide 20% of total electricity generation in the United States with an investment of less than 1% of the annual U.S. budget.

The concept is known as agrivoltaics – using the same land for both growing crops and generating solar energy.  The proponents of agrivoltaics say that it provides more food, more energy, lower water demand, lower carbon emissions, and more prosperous rural communities.

According to the study, wide-scale installation of agrivoltaic systems could lead to an annual reduction of 330,000 tons of carbon dioxide emission in the U.S. – the equivalent of taking 75,000 cars off the road – and the creation of more than 100,000 jobs in rural communities.  All of this could be achieved with minimal effects on crop yields.

The study finds that an area about the size of Maryland would be needed for agrivoltaics to produce 20% of U.S. electricity generation.  That area of 13,000 square miles constitutes about 1% of current U.S. farmland.

The cost of the solar installations would be $1.1 trillion over 35 years and they would pay for themselves from the electricity generated within 17 years.  Installing the arrays would create the equivalent of 117,000 jobs lasting 20 years.

The researchers are going to install a fully functional solar farm on 5 acres of university owned land to demonstrate to the agricultural community and potential future funders how the study’s findings can be applied in real world agricultural systems.

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Combining solar energy and agriculture to mitigate climate change, assist rural communities

Photo, posted October 11, 2011, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Short-Lived Climate Forcing Pollutants | Earth Wise

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When talking about the causes of climate warming, it is common practice to bundle together various pollutants and express their effects in terms of “CO2 equivalence.”  This involves comparing climate effects of the pollutants on a 100-year timescale.  Recent research from the Institute for Advanced Sustainability Studies in Germany points out the problems with this approach.

One of the worst qualities of carbon dioxide is that it accumulates in the atmosphere.  Once it gets there, it stays there for anywhere from decades to millennia.  On the other hand, short-lived climate forcing pollutants – or SLCPs – stay in the atmosphere for significantly shorter periods.  However, some of these are far more effective at trapping heat in the atmosphere.  As a result, the atmosphere and climate system react much more quickly to reductions in the emission of these pollutants.

The IASS research study determined that reducing SLCP emissions is an important way to slow near-term climate warming as well as having other positive benefits such as reducing air pollution and improving crop yields.  A number of studies indicate that a rapid reduction in SLCP emissions could slow the rate of climate change and reduce the risk of triggering dangerous and potentially irreversible climate tipping points.

Examples of SLCPs are the methane gas emitted from landfills and hydrofluorocarbons that are still widely used as coolants. HFCs only persist in the atmosphere for 15 years but are nearly 4,000 times more effective in trapping heat over a 20-year period.

In order to mitigate the most harmful consequences of climate change, we need to minimize both the near-term climate impacts of SLCPs and the long-term climate impacts of carbon dioxide.

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More Than Just CO2: It’s Time To Tackle Short-Lived Climate-Forcing Pollutants

Photo, posted March 10, 2020, courtesy of Jonathan Cutrer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Decline Of Pollinators Threatens Food Security | Earth Wise

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Scientists have been sounding the alarm on the global struggle of pollinators for many years.  According to a United Nations-sponsored report, 40% of invertebrate pollinator species, including bees and butterflies, are facing extinction.  Approximately 80% of all flowering plant species, which are responsible for 35% of global food production, depend on pollination. 

According to new research led by Rutgers University, crop yields for apples, blueberries, and cherries in the United States are being reduced by a lack of pollinators.  The study, the most comprehensive of its kind to date, found that crop production would be increased if crop flowers received more pollination.  In the U.S., the production of crops that depend on pollinators generates more than $50 billion a year.    

For the study, which was recently published in the journal Proceedings of the Royal Society B, researchers collected data on insect pollination of crop flowers and yield of apples, highbush blueberries, sweet cherries, tart cherries, almonds, watermelons, and pumpkins at 131 farms across the United States and British Columbia, Canada.  Four of those seven crops – apples, blueberries, sweet cherries, and tart cherries – showed evidence of being limited by pollination, meaning that their yields are lower than they would be with full pollination. 

The researchers observed that honey bees and wild bees provided similar amounts of overall pollination, so managing habitat for native bee species or stocking more honey bees would boost pollination levels and, in turn, crop production.

Bees and other pollinators play a critical role in food production, and their continued decline could have devastating consequences.

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Decline of bees, other pollinators threatens US crop yields

Photo, posted April 22, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Plants Plump

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The leading cause of crop failures worldwide is drought.  Ironically, the very close runner-up is flooding.  Facing a changing and increasingly erratic climate, farmers need all the help they can get in protecting their crops.

Researchers at the University of California, Riverside, have created a chemical to help plants hold onto water, which could stem the tide of massive annual crop losses from drought.  Details of the team’s work is described in a paper published in Science.

The chemical is called Opabactin, but is also known as “OP.” OP is gamer slang for overpowered, referring to the best character or weapon in a game.

OP mimics abscisic acid, or ABA, which is the natural hormone produced by plants in response to drought stress.  ABA slows a plant’s growth, so it doesn’t consume more water than is available and doesn’t wilt.  OP is 10-times stronger than ABA, which makes it a super hormone.  It works fast.  Within hours, there is a measurable improvement in the amount of water plants release.  Because it works so quickly, OP could give farmers more flexibility in how they deal with drought.   Plants can’t predict the future, but if, for example, farmers think there is a reasonable chance of drought, they could make decisions such as to apply OP to improve crop yields.

The research team is now trying to find a second chemical tool.  Whereas OP slows down plant growth, the team wants to find a molecule that will accelerate it.  Such a molecule could be useful in controlled environments such as indoor greenhouses.  There are times when you want to speed up growth and times when you want to slow it down.

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Game changer: New chemical keeps plants plump

Photo, posted June 7, 2013, courtesy of Bayer CropScience UK via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Agrivoltaics

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A new study by Oregon State University has found that the most productive places on Earth for solar power are farmlands.   In fact, if less than 1% of agricultural land was converted to solar panels, it would be sufficient to fulfill global electricity demand.

The concept of co-developing the same area of land for both solar photovoltaic power and conventional agriculture is known as agrivoltaics.

The synergy between agriculture and solar power is not surprising.   People have been growing crops around the planet for at least 8,000 years and, long ago, farmers found the best places to grow them which turn out to also the best places to harvest solar energy.  The needs for solar panels are pretty similar to those of food crops.  The efficiency of the panels decreases if they get too hot.  Barren land is hotter than cropland, so the productivity of solar panels is less in such places.

The Oregon State Study analyzed power production data collected by Tesla, which had installed five large grid-tied, ground-mounted solar electric arrays owned by Oregon State.  The researchers monitored air temperature, relative humidity, wind speed, wind direction, soil moisture, and incoming solar energy.  With the data, they developed a model for the best conditions for solar panel productivity and they coincide with excellent conditions for agriculture.  Solar panels are kind of like people with regard to the weather:  they are happier when it is cool and breezy and dry.

Previously-published research shows that solar panels actually increase crop yields on pasture or agricultural fields.

These new results have implications for the current practice of constructing large solar arrays in deserts.  Agricultural lands may be a much better option for both solar production and crop production.

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Installing solar panels on agricultural lands maximizes their efficiency, new study shows

Photo, posted April 20, 2011, courtesy of U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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