It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, July 02, 2021
UMaine-led study: Imaging spectroscopy can predict water stress in wild blueberry fields
Imaging spectroscopy can help predict water stress in wild blueberry barrens, according to a University of Maine-led study.
The technology involves measuring the light reflected off of objects depicted in images captured by drones, satellites and other remote sensing technology to classify and gather pertinent information about the objects. According to researchers, it can precisely measure light across dozens, if not hundreds, of bands of colors. The reflectance spectra can depict nutrient levels, chlorophyll content and other indicators of health for various crops, according to researchers.
Scientists from UMaine, the Schoodic Institute and Wyman's, one of the world's largest purveyors of wild blueberries and the number one brand of frozen fruit in the country, found in their research that when incorporated into models, imaging spectroscopy can help predict whether wild blueberry fields will lack sufficient water for growing. Not only can the technology help inform growers as they evaluate irrigation routines and manage their water resources in a way that avoids damaging the crop, researchers say.
The team collected imaging spectroscopy data by deploying a drone equipped with a spectrometer for capturing visible and near-infrared light to photograph wild blueberry fields owned by Wyman's in Debois, Maine. Researchers then processed the images to measure reflected light spectra from the plants for indications of chlorophyll levels and other properties that would help estimate their water potential, which, they say, is the primary force driving water flow and an indicator of water stress. At the same time, the group collected small branches with leaves from wild blueberry plants in the plots to assess their water potential and validate the spectra-based estimation. Pictures and samples were collected in the spring and summer of 2019 when the plants experienced peak bloom, green fruit and color break.
The data from both drone images and ground samples were incorporated into models, which they developed using machine learning and statistical analysis, to estimate water potential, and thereby predict water stress, of the plants in the barrens. Models from the ground sample data were used to help guide the development of and validate the model created with data from the images. The results of both sets of models were comparable, demonstrating that imaging spectroscopy can accurately predict water stress in wild blueberry barrens at different times of the growing season. With the efficacy of the technology confirmed, researchers say scientists can capitalize on the benefits of it, such as conducting repeated measurements on small objects like blueberry leaves with ease.
Graduate student Catherine Chan led the study, joined by UMaine faculty Daniel Hayes and Yongjiang Zhang, Schoodic Institute forest ecologist Peter Nelson and Wyman's agronomist Bruce Hall. The journal Remote Sensing published a report of their findings.
"We couple spectral data and areas of known water potential in wild blueberry fields through machine learning, creating a model to further predict areas that may be water stressed," Chan says.
Understanding how to sustainably manage water resources to mitigate risk associated with current and increasing drought frequency is crucial to wild blueberry growers, researchers say.
"This research provides key learnings to ensure the continued viability of wild blueberry crops for generations to come," Hall says.
Warming and drought exacerbated by climate change have compounded their struggles in recent years, alongside freezing and pathogens. Researchers say as a result, there has been an increased need for predictive tools, like imaging spectroscopy and models that rely on it, for land conditions to inform mitigation strategies.
Nelson says the study was conducted in cooperation with his laboratory of ecological spectroscopy (lecospec) at the Schoodic Institute, which was financed by the Maine Economic Improvement Fund, Maine Space Grant Consortium, the National Aeronautics and Space Administration (NASA) and other University of Maine System funds. The research team used a software he developed with Chan and other students that allows drones and spectrometers to measure light across dozens or hundreds of more bands of color than an average camera, Nelson says.
"We envisioned and continue to promote this as a research and application tool to produce data and algorithms applied to questions and problems in forest, agricultural and marine sectors of Maine's economy," he says.
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Cleaner air has boosted US corn and soybean yields, Stanford-led research shows
IMAGE: SOY BEANS IN A FIELD READY FOR HARVEST IN FENTON, ILLINOIS. view more
CREDIT: KELLY SIKKEMA / UNSPLASH
A key factor in America's prodigious agricultural output turns out to be something farmers can do little to control: clean air. A new Stanford-led study estimates pollution reductions between 1999 and 2019 contributed to about 20 percent of the increase in corn and soybean yield gains during that period - an amount worth about $5 billion per year.
The analysis, published this week in Environmental Research Letters, reveals that four key air pollutants are particularly damaging to crops, and accounted for an average loss of about 5 percent of corn and soybean production over the study period. The findings could help inform technology and policy changes to benefit American agriculture, and underscore the value of reducing air pollution in other parts of the world.
"Air pollution impacts have been hard to measure in the past, because two farmers even just 10 miles apart can be facing very different air quality. By using satellites, we were able to measure very fine scale patterns and unpack the role of different pollutants," said study lead author David Lobell, the Gloria and Richard Kushel Director of the Center on Food Security and the Environment.
The research highlights the considerable power of satellites to illuminate pollution impacts at a scale not possible otherwise. That power could be of even greater value in countries with less access to air monitors and yield data.
Reading the air
Scientists have long known that air pollution is toxic to plant life in high doses, but not how much farmers' yields are actually hurt at current levels. The impact of pollution on agriculture overall, as well as the effects of individual pollutants, has also remained unknown.
Focusing on a nine-state region (Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, South Dakota and Wisconsin) that produces roughly two-thirds of national maize and soybean output, Lobell and study co-author Jennifer Burney, an associate professor of environmental science at the University of California, San Diego, set out to measure the impact on crop yields of ozone, particulate matter, nitrogen dioxide and sulfur dioxide.
Ozone is the result of heat and sunlight-driven chemical reactions between nitrogen and hydrocarbons, such as those found in car exhaust. Particulate matter refers to large particles of dust, dirt, soot or smoke. Nitrogen dioxide and sulfur dioxide are gases released into the atmosphere primarily through the burning of fossil fuels at power plants and other industrial facilities.
"This has been a tricky problem to untangle because historically our measurements of different types of air pollutants and our measurements of agricultural yields haven't really overlapped spatially at the necessary resolution," explained Burney. "With the new high spatial resolution data, we could look at crop yields near both pollution monitors and known pollutant emissions sources. That revealed evidence of different magnitudes of negative impacts caused by different pollutants."
Lobell and Burney extended their analysis back to 1990, when Congress passed Clean Air Act amendments that resulted in significant air quality improvements across the country. The researchers looked through air pollution data from hundreds of monitoring stations around the region, federal data on power plant emissions, satellite-based observations of nitrogen dioxide around those power plants, crop yield data from federal surveys and satellite imagery, as well as weather data to account for growing season conditions known to explain crop yield variations.
Surprising findings
What Lobell and Burney discovered surprised them. Among their findings: negative effects of each of the four pollutants on corn and soybean yields, and a clear yield increase the farther away from power plants - particularly coal-burning facilities - crops were grown. The unique spatial patterns of each pollutant allowed them to disentangle the effect of each pollutant in a way that past studies could not.
The researchers estimated that total yield losses from the four pollutants averaged 5.8 percent for maize and 3.8 percent for soybean over the past two decades. Those losses declined over time as the air grew cleaner. In fact, the reduction in air pollution contributed to an estimated 4 percent growth in corn yields and 3 percent growth in soybean yields - increases that equal 19 percent of corn's overall yield gains during the timeframe and 23 percent of soybeans' overall yield gains.
"We already know that the Clean Air Act resulted in trillions of dollars of benefits in terms of human health, so I think of these billions in agricultural benefits as icing on the cake," Lobell said. "But even if it's a small part of the benefits of clear air, it has been a pretty big part of our ability to continue pushing agricultural productivity higher."
CAPTION
A farmer plants soybeans using a no-till planter in Vincennes, Indiana.
CREDIT
Brandon O'Connor / Natural Resources Conservation Service
Lobell is also a professor of Earth system science in Stanford's School of Earth, Energy & Environmental Sciences, the William Wrigley Senior Fellow at the Stanford Woods Institute for the Environment and a senior fellow at the Freeman Spogli Institute for International Studies and the Stanford Institute for Economic Policy Research. Burney also holds the Marshall Saunders Chancellor's Endowed Chair in Global Climate Policy and Research at UC San Diego and is a research affiliate at UC San Diego's Policy Design and Evaluation Laboratory, a fellow at the Stanford Center on Food Security and the Environment, and head of the Science Policy Fellows Program at UC San Diego.
This research was funded by NASA and the National Science Foundation.
Better predicting how plants and animals will weather climate extremes
Leading scientists argue the need to consider biomechanics
IMAGE: TREES AND OTHER ORGANISMS FACING AIR OR WATER FLOW WILL EXPERIENCE FORCES THAT COULD BEND, BREAK, OR DISLODGE THEM. BY UNDERSTANDING THE VARIABLES THAT HELP RESIST THOSE FORCES, AS WELL... view more
CREDIT: (TIM HIGHAM/UCR)
A team of scientists has devised a more accurate way to predict the effects of climate change on plants and animals -- and whether some will survive at all.
Frequently, ecologists assess an organism's fitness relative to the climate by quantifying its functional traits.
"These are physical properties you can measure -- height, diameter, the thickness of a tree," said UC Riverside biologist Tim Higham. "We believe more information is needed to understand how living things will respond to a changing world."
The team, led by Higham, outlines an alternative model for researchers in an article published today in the journal Trends in Ecology and Evolution.
This new model incorporates the functional traits of an organism as well as environmental variables, such as temperature, habitat structure, and the speed of wind or water an organism interacts with. The team calls these "ecomechanical models."
As oceans rise, strong storms will reach farther inland. The intensity of hurricanes, and the proportion of hurricanes that reach very intense levels, will likely increase with climate change. As a result, Higham said that fluids will exert greater forces on anything in their path. These forces could cause organisms with roots, such as trees, to break or be uprooted.
"If you measure the functional traits of a tree, and we know the speed of the wind, we can predict how much bending will occur," Higham said. "At certain wind speeds, the tree will potentially come down."
The way wind disperses seeds, or how insects and birds fly in the face of strong winds, can potentially influence their fitness. When considering the fate of living things, the physics governing the way they move through space is another important factor accounted for by this new framework. In this sense, ecomechanical models are not limited to understanding the impacts of climate change.
"They can help scientists understand evolutionary patterns and how animals interact differently with their environment as they grow," Higham said.
Environmental conditions can affect how some animals attach to surfaces. For example, geckos can use their famous adhesive system to attach to smooth surfaces. However, the real-world is not often smooth. Therefore, understanding how geckos attach requires knowledge of both the animal's functional traits and the environment's texture, for example.
In order to facilitate use of this model by many different types of scientists, the research team urges the expansion of freely available online databases in which functional traits of organisms have been described in a uniform, standardized way.
This work was years in the making, the product of a working group funded by the National Science Foundation. The group is composed of 24 scientists from Arizona State University; Claremont Colleges; University of British Columbia; University of Illinois, Clark University; the University of Calgary, The State University of Northern Rio de Janeiro, Brazil; Rutgers University; University of Waterloo in Ontario, Canada; University of Washington; George Washington University; Trinity University; UC Berkeley; Cornell University; Towson University, and the American Museum of Natural History.
Many of the participating faculty identify as members of underrepresented groups in science. "Including faculty in early career stages, and from a diversity of backgrounds and lived experiences was of paramount importance to us as we created the working group," said Lara Ferry, biologist and President's Professor from Arizona State University. "We know the best results come from the collective contributions of many different perspectives."
Should these recommendations become widely adopted, the research team feels there will be profound impacts on multiple areas of biology.
"The use of ecomechanical models can help us understand the rules of life," Higham said.
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Microbes in cow stomachs can break down plastic
Bacteria found in the rumen, one of the compartments that make up the cow stomach, can break down plastics, representing an eco-friendly way to reduce litter
Plastic is notoriously hard to break down, but researchers in Austria have found that bacteria from a cow's rumen - one of the four compartments of its stomach - can digest certain types of the ubiquitous material, representing a sustainable way to reduce plastic litter.
The scientists suspected such bacteria might be useful since cow diets already contain natural plant polyesters. "A huge microbial community lives in the rumen reticulum and is responsible for the digestion of food in the animals," said Dr Doris Ribitsch, of the University of Natural Resources and Life Sciences in Vienna, "so we suspected that some biological activities could also be used for polyester hydrolysis," a type of chemical reaction that results in decomposition. In other words, these microorganisms can already break down similar materials, so the study authors thought they might be able to break down plastics as well.
Ribitsch and her colleagues looked at three kinds of polyesters. One, polyethylene terephthalate, commonly known as PET, is a synthetic polymer commonly used in textiles and packaging. The other two consisted of a biodegradable plastic often used in compostable plastic bags (polybutylene adipate terephthalate, PBAT), and a biobased material (Polyethylene furanoate, PEF) made from renewable resources.
They obtained rumen liquid from a slaughterhouse in Austria to get the microorganisms they were testing. They then incubated that liquid with the three types of plastics they were testing (which were tested in both powder and film form) in order to understand how effectively the plastic would break down.
According to their results, which were recently published in Frontiers in Bioengineering and Biotechnology, all three plastics could be broken down by the microorganisms from cow stomachs, with the plastic powders breaking down quicker than plastic film. Compared to similar research that has been done on investigating single microorganisms, Ribitsch and her colleagues found that the rumen liquid was more effective, which might indicate that its microbial community could have a synergistic advantage - that the combination of enzymes, rather than any one particular enzyme, is what makes the difference.
While their work has only been done at a lab scale, Ribitsch says, "Due to the large amount of rumen that accumulates every day in slaughterhouses, upscaling would be easy to imagine." However, she cautions that such research can be cost-prohibitive, as the lab equipment is expensive, and such studies require pre-studies to examine microorganisms.
Nevertheless, Ribitsch is looking forward to further research on the topic, saying that microbial communities have been underexplored as a potential eco-friendly resource.
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Is global plastic pollution nearing an irreversible tipping point?
Common press release: Stockholm University, Norwegian Geotechnical Institute, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Helmholtz Centre for Environmental Research
IMAGE: CATCHING A BIG BLUE BARREL FLOATING ON THE OCEAN SURFACE IN THE GREAT PACIFIC GARBAGE PATCH FROM THE GERMAN RESEARCH VESSEL SONNE DURING EXPEDITION SO268/3 CROSSING THE NORTH PACIFIC OCEAN... view more
Current rates of plastic emissions globally may trigger effects that we will not be able to reverse, argues a new study by researchers from Sweden, Norway and Germany published on July 2nd in Science. According to the authors, plastic pollution is a global threat, and actions to drastically reduce emissions of plastic to the environment are "the rational policy response".
Plastic is found everywhere on the planet: from deserts and mountaintops to deep oceans and Arctic snow. As of 2016, estimates of global emissions of plastic to the world's lakes, rivers and oceans ranged from 9 to 23 million metric tons per year, with a similar amount emitted onto land yearly. These estimates are expected to almost double by 2025 if business-as-usual scenarios apply.
"Plastic is deeply engrained in our society, and it leaks out into the environment everywhere, even in countries with good waste-handling infrastructure," says Matthew MacLeod, Professor at Stockholm University and lead author of the study. He says that emissions are trending upward even though awareness about plastic pollution among scientists and the public has increased significantly in recent years.
That discrepancy is not surprising to Mine Tekman, a PhD candidate at the Alfred Wegener Institute in Germany and co-author of the study, because plastic pollution is not just an environmental issue but also a "political and economic" one. She believes that the solutions currently on offer, such as recycling and cleanup technologies, are not sufficient, and that we must tackle the problem at its root.
"The world promotes technological solutions for recycling and to remove plastic from the environment. As consumers, we believe that when we properly separate our plastic trash, all of it will magically be recycled. Technologically, recycling of plastic has many limitations, and countries that have good infrastructures have been exporting their plastic waste to countries with worse facilities. Reducing emissions requires drastic actions, like capping the production of virgin plastic to increase the value of recycled plastic, and banning export of plastic waste unless it is to a country with better recycling" says Tekman.
A poorly reversible pollutant of remote areas of the environment
Plastic accumulates in the environment when amounts emitted exceed those that are removed by cleanup initiatives and natural environmental processes, which occurs by a multi-step process known as weathering.
"Weathering of plastic happens because of many different processes, and we have come a long way in understanding them. But weathering is constantly changing the properties of plastic pollution, which opens new doors to more questions," says Hans Peter Arp, researcher at the Norwegian Geotechnical Institute (NGI) and Professor at the Norwegian University of Science and Technology (NTNU) who has also co-authored the study. "Degradation is very slow and not effective in stopping accumulation, so exposure to weathered plastic will only increase," says Arp. Plastic is therefore a "poorly reversible pollutant", both because of its continuous emissions and environmental persistence.
Remote environments are particularly under threat as co-author Annika Jahnke, researcher at the Helmholtz Centre for Environmental Research (UFZ) and Professor at the RWTH Aachen University explains:
"In remote environments, plastic debris cannot be removed by cleanups, and weathering of large plastic items will inevitably result in the generation of large numbers of micro- and nanoplastic particles as well as leaching of chemicals that were intentionally added to the plastic and other chemicals that break off the plastic polymer backbone. So, plastic in the environment is a constantly moving target of increasing complexity and mobility. Where it accumulates and what effects it may cause are challenging or maybe even impossible to predict."
A potential tipping point of irreversible environmental damage
On top of the environmental damage that plastic pollution can cause on its own by entanglement of animals and toxic effects, it could also act in conjunction with other environmental stressors in remote areas to trigger wide-ranging or even global effects. The new study lays out a number of hypothetical examples of possible effects, including exacerbation of climate change because of disruption of the global carbon pump, and biodiversity loss in the ocean where plastic pollution acts as additional stressor to overfishing, ongoing habitat loss caused by changes in water temperatures, nutrient supply and chemical exposure.
Taken all together, the authors view the threat that plastic being emitted today may trigger global-scale, poorly reversible impacts in the future as "compelling motivation" for tailored actions to strongly reduce emissions.
"Right now, we are loading up the environment with increasing amounts of poorly reversible plastic pollution. So far, we don't see widespread evidence of bad consequences, but if weathering plastic triggers a really bad effect we are not likely to be able to reverse it," cautions MacLeod. "The cost of ignoring the accumulation of persistent plastic pollution in the environment could be enormous. The rational thing to do is to act as quickly as we can to reduce emissions of plastic to the environment."
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Original publication:
Matthew MacLeod, Hans Peter H. Arp, Mine B. Tekman, Annika Jahnke: The global threat from plastic pollution, Science (2021). DOI: 10.1126/science.abg5433
Rethinking plastics
UD scientists and collaborators issue urgent call to action on plastics pollution
IMAGE: UNIVERSITY OF DELAWARE RESEARCHERS LASHANDA KORLEY (LEFT) AND THOMAS EPPS, III, ARE CO-AUTHORS OF A SCIENCE MAGAZINE ARTICLE CALLING FOR A CONCERTED EFFORT TO ADDRESS THE URGENT CRISIS OF PLASTICS... view more
CREDIT: GRAPHICS BY JEFFREY C. CHASE
People lived without plastic until the last century or so, but most of us would find it hard to imagine how.
Plastics now are everywhere in our lives, providing low-cost convenience and other benefits in countless applications. They can be shaped to almost any task, from wispy films to squishy children's toys and hard-core components. They have shown themselves vital in medicine and have been pivotal in the global effort to slow the spread of the COVID-19 pandemic over the past 16 months.
Plastics seem indispensable these days.
Unfortunately for the long-term, they are also nearly indestructible. Our planet now bears the weight of more than seven billion tons of plastics, with more being produced every day. An ever-growing waste stream clogs our landfills, pollutes our waterways and poses an urgent crisis for our planet.
Four scientists have published a call to action in a new issue of Science, devoted to the plastics problem.
In a sweeping introductory article, the scientists -- including two from the University of Delaware, one from the Lawrence Berkeley National Laboratory in California and another from the University of Sheffield in the United Kingdom -- call for fundamental change in the way plastics are designed, produced, used and reused.
The ultimate goal: Designing, adopting and ensuring a "circular" lifecycle for plastics that leads not to a landfill or an ocean or a roadside, but to a long life of near-infinite use and reuse of the valuable resources and applications they represent.
That requires new approaches to chemistry, engineering, industrial processes, policy and global collaboration, according to co-authors LaShanda T.J. Korley, director of the Center for Plastics Innovation (CPI) at the University of Delaware and the principal investigator of a National Science Foundation (NSF) Partnerships for International Research and Education effort in Bio-inspired Materials and Systems; UD's Thomas H. Epps, III, co-director of CPI, lead principal investigator of an NSF Growing Convergence Research (GCR) effort in Materials Life-Cycle Management and director of the Center for Hybrid, Active, and Responsive Materials (CHARM) at UD; Brett A. Helms of the Molecular Foundry at Lawrence Berkeley National Laboratory in California; and Anthony J. Ryan of the Grantham Centre for Sustainable Futures at the University of Sheffield in the United Kingdom.
"The plastics waste dilemma is a global challenge that requires urgent intervention and a concerted effort that links partners across industrial, academic, financial, and government sectors buttressed by significant investments in sustainability," they write.
It's a tall order that includes attention to recycling, "upcycling" (reusing materials in new added-value ways), development of new materials and recognition of the needs of under-resourced communities.
"There's not a one-size-fits-all solution," said Korley, Distinguished Professor of Materials Science and Engineering at UD, who has spent her career developing new plastics with specific properties. "How people live with waste and how they recycle is so different. Traveling in Europe has highlighted the stark contrast in the usage of single-use plastics, such as drinking straws and cutlery in comparison to the U.S. Across the U.S., cities and municipalities within a single state may do things differently."
Complex recipes are used in many plastics, Korley said, and often include several kinds of polymers and other additives. Each component can complicate recycling efforts or make recycling impossible, which is why recyclers will accept some kinds of plastic and refuse others.
But how can plastics be designed so that all of their components can be deconstructed for future use in other products?
This is the challenge for CPI, which Korley directs. Its focus is on "upcycling" plastics -- finding ways to turn plastic waste into valuable materials such as fuels and lubricants. Researchers use catalysis and enzymes to reconstitute some kinds of plastic, such as high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polystyrene/Styrofoam, the kinds of plastics used in milk jugs, shampoo bottles, sandwich bags, coffee cups, grocery bags and food packaging.
"Different materials properties require the use of different polymers and blends and additives, which contributes to the complexity and hierarchy of waste," Korley said.
The Science paper addresses that and much more, with an urgency that reflects the real and present dangers for a planet choked by discarded plastics that aren't going anywhere anytime soon.
Some of those realities are grim indeed. Take the plastic water bottle that helped quench your thirst after a morning jog five years ago, for example. It will probably be with us -- somewhere -- for another 395 years. Slow deterioration doesn't help us either. Scientists have found that tiny micro bits of worn-down plastic are prevalent in the water we drink and the foods we eat.
Less than 10% of plastic waste is recycled at all and less than 1% will be recycled more than once. About 12% will be incinerated. Millions of tons of discarded plastic winds up in giant swirls of debris in the ocean and the rest of it piles up in landfills, sinks into riverbeds or lies on roadsides around the world.
But Helms, a co-author from the Lawrence Berkeley National Lab, was part of the team that created a next-generation plastic called PDK (polydiketoenamine), which can be reduced back to its molecular parts and reassembled as needed.
"We're at a critical point where we need to think about the infrastructure needed to modernize recycling facilities for future waste sorting and processing," Helms said after the new material was announced. "If these facilities were designed to recycle or upcycle PDK and related plastics, then we would be able to more effectively divert plastic from landfills and the oceans. This is an exciting time to start thinking about how to design both materials and recycling facilities to enable circular plastics."
The building blocks of plastics -- monomers -- are made up of elements including carbon, hydrogen, oxygen, nitrogen, chlorine and sulfur. These monomers are linked by chemical bonds to become polymers, which can be used in the formation of plastics to be crafted into various forms for many different uses.
The value of all those resources is lost in single-use applications, said Sheffield's Ryan. He calls it a "convenient truth" -- the convenience and cheap cost of such products make them compelling to consumers, without recognizing the inherent value and cost to the planet. Marketing strategies that claim certain plastic products are "green" and biodegradable to draw well-intentioned consumers are especially concerning to him.
"Cynical 'greenwash' is the biggest problem for plastics sustainability," he said. "So I was very keen to work with LaShanda and Thomas on this. I have known them since they were Ph.D. students."
With innovation and collaboration as pillars of the new centers they co-direct -- Korley's U.S. Department of Energy-backed CPI and Epps' NSF-backed CHARM and GCR, Korley and Epps, the Allan and Myra Ferguson Distinguished Professor of Chemical and Biomolecular Engineering, are at the forefront of efforts to extend the life of petroleum- and bio-derived plastics and/or put them on a circular path that continues from production to first use to reconstitution to forever.
Ryan said he sees a "circular economy" as critical. He sees the value in recycling and upcycling and development of new materials, but none is a "silver bullet." Addressing the plastics dilemma requires recognition of the true value of plastics.
"One solution is something America is not very good at -- regulations, policy and taxation," he said. "There isn't an easy answer to the plastics problem. An unrestrained market isn't going to provide it.
"For all of these issues where science and engineering and society intersect, the answer is always: It's complicated."
A more accurate perspective, in Ryan's view, is to see the plastics problem as related to the climate change problem without allowing it to be a distraction.
"Climate change is an inconvenient truth and an invisible truth," he said. "You can't see what's causing it and you can't see carbon dioxide in the atmosphere. You don't associate driving to the store with climate change.
"You do associate things with plastics waste -- and that is a convenient truth. We have no problem taking fossil fuels and turning them into plastics. But now we need to take care of that precious plastic. Don't just throw it away. It's just too cheap. Because of the pollution problem, we need to give it an artificially high price."
Lifecycle analysis data are key to making evidence-based decisions, Ryan said, and consumers and lawmakers can't do that on their own. They need professionals to break down the costs and benefits and explain the options.
"It's far more complex than most people are willing to consider," he said.
The call to action is comprehensive.
"To achieve a more sustainable future, integration of not only technological considerations, but also equity analysis, consumer behavior, geographical demands, policy reform, life-cycle assessment, infrastructure alignment, and supply chain partnerships are vital," the authors said.
Korley said she sees growing passion for this daunting challenge.
"These initiatives drive excitement among our students -- high school, undergraduate and graduate and our postdocs," she said. "People are passionate about doing something to better the world. And they can talk to their grandmother or their niece or nephew and explain why the work they are doing matters."
Reducing plastic waste will require fundamental change in culture
Packaging
INSTITUTE FOR ADVANCED SUSTAINABILITY STUDIES E.V. (IASS)
Plastic waste is considered one of the biggest environmental problems of our time. IASS researchers surveyed consumers in Germany about their use of plastic packaging. Their research reveals that fundamental changes in infrastructures and lifestyles, as well as cultural and economic transformation processes, are needed to make zero-waste shopping the norm.
96 percent of the German population consider it important to reduce packaging waste. Nevertheless, the private end consumption of packaging in Germany has increased continuously since 2009. At 3.2 million tons in 2018, the amount of plastic packaging waste generated by end consumers in Germany has more than doubled since 1997. At 228 kilograms per capita, packaging consumption in Germany was significantly higher than the European average of 174 kilos per capita.
"Recycling only treats the symptoms of the plastic crisis and does not address the root cause, waste generation itself. We wanted to learn more about the barriers that prevent individuals in Germany from reducing their everyday consumption of plastic packaging for food and beverages. For our research project, a total of 40 participants contributed to discussions in four focus groups," explains Jasmin Wiefek, lead author of the study.
In their analysis of the discussions, the researchers identified twelve barriers to reducing plastic packaging consumption:
Habits: The focus group participants mainly shop at supermarkets or discounters rather than markets or zero-waste shops. The discussion also revealed that most participants do not take their own bags or containers when they go grocery shopping. Processed and packaged foods are popular.
Lack of knowledge: The researchers observed that participants were often uncertain which types of packaging are more sustainable than others.
Hygiene: Discussions revealed that participants held reservations about the hygienic properties of freely accessible displays of unpacked goods, the use of self-brought packaging and long-term reusable packaging options in general.
Material properties: Participants often preferred plastic packaging due to their material properties (e.g., lightweight, shatterproof, tear-resistant).
Priorities: Several participants described how their efforts to use less plastic packaging clashed with other priorities in their daily lives. One example given was that parents do not want to pack heavy backpacks for their children and accordingly prefer to use plastic instead of glass bottles.
Price: In general, groceries packaged in plastics are more affordable than plastic-free groceries.
Availability: By default, most groceries offered in supermarkets and discounters are only available in plastic packaging and so participants feel that they have little choice.
Diffusion of responsibility: According to the participants, both individuals and industry have a responsibility to solve the "plastic problem": On the one hand, because industry is responsible for the fact that so many products are packaged in plastic, it must offer solutions. However, they also emphasised that consumers should shop more consciously and avoid products in plastic packaging.
Reachability & infrastructure: Participants noted that places such as zero-waste shops or weekly markets were difficult to reach and required more time and effort to access than local supermarkets or discounters.
Time and time structures: Time is another crucial barrier to plastic-free shopping. Due to the travel distances involved, accessing zero-waste shops and markets would take up more time for most people. Participants pointed out that shopping would also take longer if they filled the food in their own containers and that the containers would have to be cleaned subsequently. They also noted that preparing unprocessed foodstuffs takes more time.
Convenience: Participants reported that they find it inconvenient to take their own containers to shops as it requires that they either carry the containers to work and back again or go out twice.
Consumer Culture: The participants stated that they did not attach much importance to the availability of a 'wide range of products' when shopping. However, many stressed the importance of reliably finding specific products in shops. This translates into an indirect demand for a wide range of products, which is difficult for zero-waste / low-plastic retailers to implement. Discussions in the focus groups also showed that our culture of spontaneous and on-the-go consumption makes it difficult to reduce packaging. Many participants were unaware that non-regional and non-seasonal foods, which we consume as a matter of course every day, must be packaged to maintain their freshness during long distance transport.
"Our results show that at present a lot of effort and knowledge is required for consumers to avoid plastic packaging. If we want to make low-waste goods and goods without single-use plastic packaging the cheapest and most convenient option, we will need to change the relevant infrastructures, economic incentives, and political framework conditions," explains project leader and co-author Katharina Beyerl. The goal of reducing the use of plastic packaging will not be achieved by merely asking consumers to shop exclusively in zero-waste stores. Instead, it requires fundamental changes in societal structures and lifestyles as well as a cultural shift.
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Wiefek, J., Steinhorst, J., Beyerl, K. (2021 online): Personal and structural factors that influence individual plastic packaging consumption--Results from focus group discussions with German consumers. - Cleaner and responsible consumption, 3, 100022. https://doi.org/10.1016/j.clrc.2021.100022
Disclaimer: AAAS and E
Special issue: Our plastics dilemma
AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE
Although plastics have become an essential material, permeating almost all aspects of modern living, many of the inherent properties that make them useful in such a wide variety of applications also make them a serious environmental threat. In a special issue of Science, "Our Plastics Dilemma," four Reviews, two Perspectives, a Policy Forum, an associated Report and two News features examine a wide range of topics related to plastics and the problems they present. "As for much new technology, their development and proliferation occurred with little consideration for their impacts, but now it's impossible to deny their dark side as we confront a rapidly growing plastic pollution problem," writes Science Senior Editor, Jesse Smith. "The time for preventing plastic pollution is long past - the time for changing the future of plastics in our world, however, is now."
Estimates of the amount of plastic floating at the ocean surface (measured in the hundreds to thousands of metric tons) only represent a small fraction of what is suspected to be annually discharged by rivers worldwide (several million metric tons). This has led some to speculate a large, yet-unidentified plastic sink that could help explain the rapid removal of river-sourced plastics from the ocean's surface. In the associated Report in this special issue, Lisa Weiss and colleagues show that this missing sink may not even exist. Weiss et al. performed a large-scale statistical reanalysis on updated data on microplastics. "We came to the conclusion that previous flux estimates contained several serious errors," Weiss explains in a related video. She and colleagues say that previous mass fluxes of microplastics were overestimated by two to three orders of magnitude, explaining why the residence time of plastics in the oceans appeared so short. Based on these findings, the authors suggest that the average residence time of microplastics at the ocean's surface could be as high as several years, rather than a few days. The results imply that ocean plastics have more time than previously thought to degrade at the surface before becoming entrained in seafloor sediments. Based on their results, "the need for a missing plastic sink becomes outdated and... unnecessary," says author Wolfgang Ludwig in the video.
In a pair of Perspectives, experts highlight the problematic history of early bio-based plastics and how designing future plastics for both chemical assembly and disassembly is essential to achieving an effective circular plastics economy. According to Rebecca Altman, early bioplastics - the broad category of plastics made from bio-based feedstocks like corn, sugar or wood - were neither clean nor green. Lessons from their overlooked and misunderstood past could help inform the future of greener, biodegradable plastics and plastic technology. Sarah Kakadellis and Gloria Rosetto highlight the technical, chemical, and biological routes to closing the plastic resource loop by designing plastics to be more broadly recyclable or biodegradable in the environment. "The fallacy of mechanical recycling has already taught us that technology alone will not and cannot solve the plastic pollution crisis. No silver bullet solution exists for the multifaceted nature of plastic pollution," write the authors. "Only through committed action and coordination across the value chain will a sustainable future for plastics be secured," write Kakadellis and Rosetto.
A Policy Forum by Nils Simon and colleagues argues the need for a binding global agreement to address plastic's long lifecycle and to combat plastic pollution. According to Simon et al., the international community has tended to view the plastics problem as an ocean- and/or waste-focused problem. However, plastics are ubiquitously found in increasing amounts worldwide, including in terrestrial environments and even inside the human body. The authors call for a new international treaty that addresses these concerns thought the entire lifecycle of plastics, from the extraction of the raw materials needed for its manufacture to its legacy pollution.
The special issue also includes four Reviews that discuss the rapidly rising global threat that steadily accumulating plastic pollution poses for the environment, the evolutionary and ecological consequences of widespread plastic ingestion by wildlife, how plastics are best understood as emergent geomaterials with unique synthetic chemistries not previously seen in Earth's history, and how innovations in plastic recycling and polymer upcycling could help address our plastics dilemma and usher in the next generation of materials design. In addition, two features from Science's news department explore how enzymes are being used to aid in plastic recycling efforts and the ways in which museum conservationists are trying to preserve the plastic objects in their exhibits.
