Micro-Naps for Plants: Flicking the Lights on and off Can Save Energy Without Hurting Indoor Agriculture Harvests
By Kevin M. Folta
A nighttime arrival at Amsterdam's Schiphol Airport flies you over the bright pink glow of vegetable production greenhouses. Growing crops under artificial light is gaining momentum, particularly in regions where produce prices can be high during seasons when sunlight is sparse.
The Netherlands is just one country that has rapidly adopted controlled-environment agriculture, where high-value specialty crops like herbs, fancy lettuces and tomatoes are produced in year-round illuminated greenhouses. Advocates suggest these completely enclosed buildings – or plant factories – could be a way to repurpose urban space, decrease food miles and provide local produce to city dwellers.
One of the central problems of this process is the high monetary cost of providing artificial light, usually via a combination of red and blue light-emitting diodes. Energy costs sometimes exceed 25% of the operational outlay. How can growers, particularly in the developing world, compete when the sun is free? Higher energy use also translates to more carbon emissions, rather than the decreased carbon footprint sustainably farmed plants can provide.
I've studied how light affects plant growth and development for over 30 years. I recently found myself wondering: Rather than growing plants under a repeating cycle of one day of light and one night of darkness, what if the same daylight was split into pulses lasting only hours, minutes or seconds?
Short Bursts of Light and Dark
So my colleagues and I designed an experiment. We'd apply the normal amount of light in total, just break it up over different chunks of time.
Of course plants depend on light for photosynthesis, the process that in nature uses the sun's energy to merge carbon dioxide and water into sugars that fuel plant metabolism. Light also directs growth and development through its signals about day and night, and monkeying with that information stream might have disastrous results.
That's because breaking something good into smaller bits sometimes creates new problems. Imagine how happy you'd be to receive a $100 bill – but not as thrilled with the equivalent 10,000 pennies. We suspected a plant's internal clock wouldn't accept the same luminous currency when broken into smaller denominations.
And that's exactly what we demonstrated in our experiments. Kale, turnip or beet seedlings exposed to cycles of 12 hours of light, 12 hours dark for four days grew normally, accumulating pigments and growing larger. When we decreased the frequency of light-dark cycles to 6 hours, 3 hours, 1 hour or 30 minutes, the plants revolted. We delivered the same amount of light, just applied in different-sized chunks, and the seedlings did not appreciate the treatment.
The same amount of light applied in shorter intervals over the day caused plants to grow more like they were in darkness. We suspect the light pulses conflicted with a plant's internal clock, and the seedlings had no idea what time of day it was. Stems stretched taller in an attempt to find more light, and processes like pigment production were put on hold.
But when we applied light in much, much shorter bursts, something remarkable happened. Plants grown under five-second on/off cycles appeared to be almost identical to those grown under the normal light/dark period. It's almost like the internal clock can't get started properly when sunrise comes every five seconds, so the plants don't seem to mind a day that is a few seconds long.
Just as we prepared to publish, undergraduate collaborator Paul Kusuma found that our discovery was not so novel. We soon realized we'd actually rediscovered something already known for 88 years. Scientists at the U.S. Department of Agriculture saw this same phenomenon in 1931 when they grew plants under light pulses of various durations. Their work in mature plants matches what we observed in seedlings with remarkable similarity.
A 1931 study by Garner and Allard tracked the growth of Yellow Cosmos flowers under light pulses of various durations.
J. Agri. Res. 42: National Agricultural Library, Agricultural Research Service, U.S. Department of Agriculture., CC BY-ND
Not only was all of this a retread of an old idea, but pulses of light do not save any energy. Five seconds on and off uses the same amount of energy as the lights being on for 12 hours; the lights are still on for half the day.
But what would happen if we extended the dark period? Five seconds on. Six seconds off. Or 10 seconds off. Or 20 seconds off. Maybe 80 seconds off? They didn't try that in 1931.
Building in Extra Downtime
It turns out that the plants don't mind a little downtime. After applying light for five seconds to activate photosynthesis and biological processes like pigment accumulation, we turned the light off for 10, or sometimes 20 seconds. Under these extended dark periods, the seedlings grew just as well as they had when the light and dark periods were equal. If this could be done on the scale of an indoor farm, it might translate to a significant energy savings, at least 30% and maybe more.
Recent yet-to-be published work in our lab has shown that the same concept works in leaf lettuces; they also don't mind an extended dark time between pulses. In some cases, the lettuces are green instead of purple and have larger leaves. That means a grower can produce a diversity of products, and with higher marketable product weight, by turning the lights off.
One variety of lettuce grew purple when given a 10-second dark period. They look similar to those grown with a five-second dark period, yet use 33% less energy. Extending the dark period to 20 seconds yielded green plants with more biomass.
J. Feng, K. Folta
Learning that plants can be grown under bursts of light rather than continuous illumination provides a way to potentially trim the expensive energy budget of indoor agriculture. More fresh vegetables could be grown with less energy, making the process more sustainable. My colleagues and I think this innovation could ultimately help drive new business and feed more people – and do so with less environmental impact.
Kevin M. Folta is a professor of horticultural sciences and plant molecular and cellular biology at the University of Florida.
Disclosure statement: Kevin M. Folta received funding from the United States Department of Agriculture National Institute of Food and Agriculture and Vindara Inc to work on questions in agricultural lighting. He is affiliated with Eggsotics Eggs and Produce where his family grows some direct-market produce under hydroponic and/or artificial light conditions. He is reimbursed for travel related to talks in research and science communication. A full list of prior research funding may be seen at www.kevinfolta.com/transparency.
Reposted with permission from our media associate The Conversation.
- Three Simple Steps for Planting a Chaos Garden - EcoWatch ›
- China Says It Has Sprouted Plants on the Moon - EcoWatch ›
- 7 Science-Backed Health Benefits of Having Plants at Home ... ›
By Asher Rosinger
Imagine seeing a news report about lead contamination in drinking water in a community that looks like yours. It might make you think twice about whether to drink your tap water or serve it to your kids – especially if you also have experienced tap water problems in the past.
In a new study, my colleagues Anisha Patel, Francesca Weaks and I estimate that approximately 61.4 million people in the U.S. did not drink their tap water as of 2017-2018. Our research, which was released in preprint format on April 8, 2021, and has not yet been peer reviewed, found that this number has grown sharply in the past several years.
Other research has shown that about 2 million Americans don't have access to clean water. Taking that into account, our findings suggest that about 59 million people have tap water access from either their municipality or private wells or cisterns, but don't drink it. While some may have contaminated water, others may be avoiding water that's actually safe.
Water insecurity is an underrecognized but growing problem in the U.S. Tap water distrust is part of the problem. And it's critical to understand what drives it, because people who don't trust their tap water shift to more expensive and often less healthy options, like bottled water or sugary drinks.
I'm a human biologist and have studied water and health for the past decade in places as diverse as Lowland Bolivia and northern Kenya. Now I run the Water, Health, and Nutrition Laboratory at Pennsylvania State University. To understand water issues, I talk to people and use large datasets to see whether a problem is unique or widespread, and stable or growing.
An Epidemic of Distrust
According to our research, there's a growing epidemic of tap water distrust and disuse in the U.S. In a 2020 study, anthropologist Sera Young and I found that tap water avoidance was declining before the Flint water crisis that began in 2014. In 2015-2016, however, it started to increase again for children.
Our new study found that in 2017-2018, the number of Americans who didn't drink tap water increased at an alarmingly high rate, particularly for Black and Hispanic adults and children. Since 2013-2014 – just before the Flint water crisis began – the prevalence of adults who do not drink their tap water has increased by 40%. Among children, not consuming tap has risen by 63%.
To calculate this change, we used data from the National Health and Nutrition Examination Survey, a nationally representative survey that releases data in two-year cycles. Sampling weights that use demographic characteristics ensure that the people being sampled are representative of the broader U.S. population.
Racial Disparities in Tap Water Consumption
Communities of color have long experienced environmental injustice across the U.S. Black, Hispanic and Native American residents are more likely to live in environmentally disadvantaged neighborhoods, with exposure to water that violates quality standards.
Our findings reflect these experiences. We calculated that Black and Hispanic children and adults are two to three times more likely to report not drinking their tap water than members of white households. In 2017-2018, roughly 3 out of 10 Black adults and children and nearly 4 of 10 Hispanic adults and children didn't drink their tap water. Approximately 2 of 10 Asian Americans didn't drink from their tap, while only 1 of 10 white Americans didn't drink their tap water.
When children don't drink any water on a given day, research shows that they consume twice as many calories from sugary drinks as children who drink water. Higher sugary drink consumption increases risk of cavities, obesity and cardiometabolic diseases. Drinking tap water provides fluoride, which lowers the risk of cavities. Relying on water alternatives is also much more expensive than drinking tap water.
A4: Choosing to drink fluoridated tap water over sugar-sweetened beverages to quench thirst is vital to protecting… https://t.co/3tm8wuWjeZ— Oral Health Watch (@Oral Health Watch)1600795750.0
What Erodes Trust
News reports – particularly high-visibility events like advisories to boil water – lead people to distrust their tap water even after the problem is fixed. For example, a 2019 study showed that water quality violations across the U.S. between 2006 and 2015 led to increases in bottled water purchases in affected counties as a way to avoid tap water, and purchase rates remained elevated after the violation.
The Flint water crisis drew national attention to water insecurity, even though state and federal regulators were slow to respond to residents' complaints there. Soon afterward, lead contamination was found in the water supply of Newark, New Jersey; the city is currently replacing all lead service lines under a legal settlement. Elsewhere, media outlets and advocacy groups have reported finding tap water samples contaminated with industrial chemicals, lead, arsenic and other contaminants.
Many other factors can cause people to distrust their water supply, including smell, taste and appearance, as well as lower income levels. Location is also an issue: Older U.S. cities with aging infrastructure are more prone to water shutoffs and water quality problems.
It's important not to blame people for distrusting what comes out of their tap, because those fears are rooted in history. In my view, addressing water insecurity requires a two-part strategy: ensuring that everyone has access to clean water, and increasing trust so people who have safe water will use it.
As part of his proposed infrastructure plan, President Joe Biden is asking Congress for $111 billion to improve water delivery systems, replace lead pipelines and tackle other contaminants. The plan also proposes improvements for small water systems and underserved communities.
These are critical steps to rebuild trust. Yet, in my view, the U.S. Environmental Protection Agency should also provide better public education about water quality testing and targeted interventions for vulnerable populations, such as children and underserved communities. Initiatives to simplify and improve water quality reports can help people understand what's in their water and what they can do if they think something is wrong with it.
Who delivers those messages is important. In areas like Flint, where former government officials have been indicted on charges including negligence and perjury in connection with the water crisis, the government's word alone won't rebuild trust. Instead, community members can fill this critical role.
Another priority is the 13%-15% of Americans who rely on private well water, which is not regulated under the Safe Drinking Water Act. These households are responsible for their own water quality testing. Public funding would help them test it regularly and address any problems.
Public distrust of tap water in the U.S. reflects decades of policies that have reduced access to reliable, safe drinking water in communities of color. Fixing water lines is important, but so is giving people confidence to turn on the tap.
Asher Rosinger is an assistant professor of biobehavioral health, anthropology, and demography and director of the Water, Health, and Nutrition Laboratory at Penn State University.
Disclosure statement: Asher Rosinger receives funding from the National Science Foundation on an unrelated project. This work was supported by the Ann Atherton Hertzler Early Career Professorship funds, and the Penn State Population Research Institute (NICHD P2CHD041025). The funders had no role in the research or interpretation of results.
Reposted with permission from The Conversation.
- Life-Saving Drinking Water Disinfectants Have a 'Dark Side ... ›
- Tap Water Safety: There's Good News and Bad News - EcoWatch ›
- How Healthy Is America's Public Health Infrastructure? - EcoWatch ›
- 170 Million Americans Drink Radioactive Tap Water - EcoWatch ›
- Report: 64% of Bottled Water Is Tap Water, Costs 2000x More ... ›
A new report promoting urgent climate action in Australia has stirred debate for claiming that global temperatures will rise past 1.5 degrees Celsius in the next decade.
Australia's Climate Council released the report on Thursday. The council is an independent organization of climate scientists and experts on health, renewable energy and policy who work to inform the Australian public on the climate crisis. But their latest claim is causing controversy.
"Multiple lines of evidence show that limiting global warming to 1.5°C above the preindustrial level, without significant overshoot and subsequent drawdown, is now out of reach due to past inaction," Dr. Kevin Trenberth of the National Center for Atmospheric Research and Prof. Christopher Field of the Stanford Woods Institute for the Environment wrote in the foreword. "The science is telling us that global average temperature rise will likely exceed 1.5°C during the 2030s, and that long-term stabilization at warming at or below 1.5°C will be extremely challenging."
The report is titled "Aim high, go fast: Why emissions need to plummet this decade," and as the name suggests, it is ultimately concerned with urging more robust climate action on the part of the Australian government. The report calls for the country to reduce emissions by 75 percent by 2030 and reach net zero by 2035 in order to achieve the long-term goals of the Paris agreement, which means limiting warming to well below two degrees Celsius.
"The world achieving net zero by 2050 is at least a decade too late and carries a strong risk of irreversible global climate disruption at levels inconsistent with maintaining well-functioning human societies," the authors wrote.
The report further argues that global temperatures are likely to exceed 1.5 degrees Celsius in the 2030s based on existing temperature increases; locked-in warming from emissions that have already occurred; evidence from past climate changes and the percentage of the carbon budget that has already been used.
The report isn't a call to give up on the Paris agreement. It is possible that global temperatures could swell past 1.5 degrees Celsius but still be reduced by removing carbon dioxide from the atmosphere. Even if temperatures do exceed 1.5 degrees, every degree of warming that can be prevented makes a difference.
"Basically we can still hold temperature rise to well below 2C and do that without overshoot and drawdown," Will Steffen, lead report author from the Australian National University's Climate Change Institute, told Australia's ABC News. "Every tenth of a degree actually does matter — 1.8C is better than 1.9C, and is much better than 2C."
However, some outside scientists question both the accuracy and effectiveness of the report's claim. Both Adjunct Professor Bill Hare from Murdoch University and Dr. Carl-Freidrich Schleussner from Humboldt University told ABC News they have been trying to contact the Climate Council about its 1.5 overshoot claim for months. They said that it went against other major reports, including the UN Environment Program Gap Report and the recent Intergovernmental Panel on Climate Change Special Report on 1.5˚C.
"The big challenge their report reinforces is the need for urgent action to get on that 1.5C pathway, [so] it's very paradoxical to me that they've chosen to attack that target," Dr. Hare told ABC News.
However, Scientist Andy Pitman from the Center of Excellence for Climate Extremes at the University of New South Wales told The Guardian that the report's assessment was correct.
"It's simply not possible to limit warming to 1.5C now," he said. "There's too much inertia in the system and even if you stopped greenhouse gas emissions today, you would still reach 1.5C [of heating]."
However, one aspect everyone agreed on involved the importance of lowering emissions as soon as possible.
"[There is] absolute fundamental agreement on the task at hand, which is to get emissions to plummet," Simon Bradshaw, report author and Climate Council head of research, told The Guardian.
French winemakers are facing devastating grape loss from the worst frost in decades, preceded by unusually warm temperatures, highlighting the dangers to the sector posed by climate change.
"An important share of the harvest has been lost. It's too early to give a percentage estimate, but in any case it's a tragedy for the winegrowers who have been hit," said Christophe Chateau, director of communications at the Bordeaux Wine Council, told CNN.
Climate change, caused by the extraction and combustion of fossil fuels, has pushed winegrowing seasons earlier, putting crops at higher risk of cold — and wildfires supercharged by climate change also threaten American vignerons and farmworkers as well.
"I think it's good for people to understand that this is nature, climate change is real, and to be conscious of the effort that goes into making wine and the heartbreak that is the loss of a crop," Jeremy Seysses of Domaine Dujac in Burgundy's Côte de Nuits told Wine Enthusiast.
As reported by Wine Enthusiast:
Last week, images of candlelit French vineyards flooded social media. Across the country, winemakers installed bougies, or large wax-filled metal pots, among the vines to prevent cold air from settling in during an especially late frost.
With temperatures in early April as low as 22°F, and following an unseasonably warm March, this year's frost damage may be the worst in history for French winegrowers. Every corner of France reports considerable losses, from Champagne to Provence, and Côtes de Gascogne to Alsace. As a result, there will likely be very little French wine from the 2021 vintage reaching U.S. shores.
For a deeper dive:
- Climate Crisis Could Destroy Most Vineyards - EcoWatch ›
- Sustainable Wine Is Less Damaging to the Environment, But How ... ›
- In Europe, Climate Change Brings New Crops and Ideas - EcoWatch ›
- California Winery Cuts Carbon Emissions With Lighter Bottles ... ›
Climate change could make it harder to find a good cup of coffee, new research finds. A changing climate might shrink suitable areas for specialty coffee production without adaptation, making coffee taste blander and impacting the livelihoods of small farms in the Global South.
Published in Scientific Reports on Wednesday, the study focused on regions in Ethiopia, Africa's largest coffee-producing nation. Although studies have previously documented the impact of climate change on coffee production, what's less understood is how varying climates could change the flavors of specialty coffee, the researchers wrote.
The team aimed to fill this gap. Their results provide a glimpse into how future climate change could impact local regions and economies that rely on coffee cultivation, underscoring the value of local adaptation measures.
Researchers analyzed how 19 different climate factors, such as mean temperatures and rainfall levels, would affect the cultivation of five distinct specialty coffee types in the future, the Potsdam Institute for Climate Impact Research (PIK) reported. Although researchers found that areas suitable for growing "average quality coffee" may actually increase over time with climate change, regions where specialty coffee is grown will shrink — a pending problem in light of the global demand for high-quality coffee.
"This is an issue not just for coffee lovers, but for local agricultural value creation," Abel Chemura, the study's lead author, told the PIK.
Coffee profiles rely on specific climate patterns for their unique flavors, levels of acidity and fragrances. But in a warmer climate, the coffee cherry — the fruit picked from a coffee plant — matures faster than the bean inside, making for a lower quality cup of coffee, the PIK reported.
For example, the sought-after Yirgacheffe variety of coffee, which is cultivated in southwestern Ethiopia, could lose more than 40 percent of its suitable growth area by the end of the century, PIK reported. This could impact small farms and threaten Ethiopia's economy, the researchers noted.
"If one or more coffee regions lose their specialty status due to climate change this has potentially grave ramifications for the smallholder farmers in the region," Christoph Gornott, co-author of the study, told the PIK. "If they were forced to switch to growing conventional, less palatable and bitter coffee types, they would all of the sudden compete with industrial production systems elsewhere that are more efficient." In a country where coffee exports account for nearly a third of all agricultural exports, "this could prove fatal," Gornott added.
Climate change impacts on coffee production are not unique to Ethiopia. In Columbia's mountainous coffee-growing regions, temperatures are warming by 0.5 degrees Fahrenheit every decade, according to Yale Environment 360. Extreme levels of precipitation, which are becoming more common, also impact production, as they spread insect and fungal diseases.
"In earlier times, the climate was perfect for coffee," one small farmer in Columbia told Yale Environment 360. "In the period of flowering, there was summer. During harvest, there was winter. But from 2008 onward, this changed and we now don't know when it will be summer, when the coffee will blossom."
But researchers say there are glimmers of hope, emphasizing the importance of local adaptation measures that are designed for particular climates and communities. For example, in regions where temperature is an important factor for specialty coffee cultivation, the researchers suggest improved agroforestry systems that could maintain canopy temperatures, a promising step toward sustaining the "availability and taste of one of the world's most beloved beverages and, more importantly, on economic opportunities in local communities of the Global South," Gornott concluded.
By Suzanne Cords
One day Lizzie, the first-person narrator of the novel, receives an old book as a gift, with a dedication wishing the reader to be among the survivors. Like the preppers who build bunkers and stockpile supplies in remote areas to be ready for the end of the world, Lizzie is convinced that the end of the world is definitely near in times of a threatening climate disaster.
Lizzie, who lives in New York with her husband and son, is a university campus librarian. She worries about almost everything: her brother, an ex-junkie, or her dental insurance and the future in the face of the apocalypse. She is obsessed with reading reference books and articles about climate change.
She also devours words of wisdom, including about Buddhist spirituality: "A visitor once asked the old monks on Mount Athos what they did all day, and was told: We have died and we are in love with everything." But nothing can lift her spirits.
'Lizzie Is Just Like Us'
Lizzie observes rich New Yorkers plan their move to regions that are less threatened by climate change, something she simply cannot afford. Sometimes she watches disaster movies, which lead her to worry even more.
Above all, she is a gifted observer of her fellow human beings. "Young person worry: What if nothing I do matters? Old person worry: What if everything I do, does?"
Lizzie, the U.S. author told DW, is a bit like the rest of us — well aware of the climate crisis, but because she cares and worries about so many other things, that awareness falls by the wayside. That's how she felt herself, Jenny Offill said, but the more she looked into the issue, the more she saw a need for action on her part, too.
"I also was trying to see if there was a way to make it funny, because, you know, so much of the world of prepping and imagining disaster is actually sort of strangely funny."
The novel was shortlisted for the 2020 UK's Women's Prize for Fiction and has now been released in German translation.
Climate Activist With a Vision
But then, there is also this serious, scientifically based concern about what climate change means. In the past, says Offill, artists were the ones who would predict disasters; today it's the experts, as well as the students she teaches. In the end, their fears and their justified anger motivated her to take a closer look at the issue. Today, she is a climate activist herself, and is involved in initiatives along with many other artists.
Lizzie, the heroine of Weather, hasn't gotten that far. But she voices her fears, and that's a start. "Of course, the world continues to end," says Sylvia, a mentor of Lizzie's, at one point — and commences to water her garden. There is hope after all.
Reposted with permission from Deutsche Welle.
- 16 Essential Books About Environmental Justice, Racism and ... ›
- The Newest Books by Women Fighting the Climate Crisis - EcoWatch ›
- 10 Best Books On Climate Change, According to Activists - EcoWatch ›