Is sitting always bad for your mind? A new study suggests maybe not

COLORADO STATE UNIVERSITY

Research News 

IMAGE: PERSON WALKING view more 

CREDIT: COLORADO STATE UNIVERSITY

It's generally accepted health advice that adults of all ages should sit less, move more, and engage in regular exercise to feel better and reduce the risk of chronic diseases. However, when it comes to the brain and cognition, a new study of older adults from Colorado State University suggests that some sedentariness isn't all bad, so long as basic physical activity benchmarks are being met.

The research, from Assistant Professor Aga Burzynska in the CSU Department of Human Development and Family Studies, examined the association between sensor-measured physical activity and cognitive performance in a sample of 228 healthy older adults, aged 60 to 80.

Published in Psychology and Aging, the results showed that, as expected, adults who engaged in more moderate-to-vigorous activity had better speed, memory, and reasoning abilities. However, the data also revealed that adults who spent more time sedentary performed better on vocabulary and reasoning tasks.

The study could be a bit of good news for a population of Americans who spend a significant amount of time sitting for work and for leisure.

SENSITIVE MEASUREMENTS

The association between increased physical activity and improved cardiovascular and metabolic health is one that's well documented, according to Burzynska. But the link between different intensities of daily physical activity and cognitive health is less understood, especially in older adults.

"We know that as we grow older, even if we do not have any cognitive impairments, people aged 60 and up already show some decreases in speed, executive functioning, and memory. Those decreases are totally within a normal range, but this study was looking to understand how our behaviors and habits may correlate with cognitive outcomes in older age," Burzynska said.

What differentiates this study from others is the way the researchers measured daily physical activity, using scientifically validated sensors that are more accurate than your average, consumer-based activity tracker. Other studies rely on self-reported data to measure physical activity, "and we already know that people like to overestimate their daily movement and underestimate the time they spend sitting," Burzynska said.

"If you ask, 'How long did you sit today?' people will perhaps say 2 to 3 hours when the reality is more like 6 to 8 hours," she added.

Further, where other studies might use only one or two measures of cognition and a general definition of physical activity, Burzynska's study employed a broad assessment that tested 16 cognitive tasks. In addition, they measured and controlled for socioeconomic and health factors, such as employment status, income level, aerobic fitness, blood pressure, and mobility issues.

"Our study has pretty high-quality measures that cannot be done 'quick and dirty'," Burzynska said.

Older adults who participated in the study wore the sensor on their hip for a span of seven days, during which the sensor captured the daily time they spent sitting or in light versus moderate-to-vigorous physical activity.

FLUID VS. CRYSTALLIZED COGNITION

The cognitive assessment prompted participants to select patterns, fill-in-the-blanks, and identify shapes, among other tasks -- the results of which helped researchers gauge if there was a correlation between physical activity and fluid vs. crystallized cognition.

So-called "fluid" abilities, such as speed and memory, problem solving, and reasoning skills, tend to decline throughout adulthood; yet, participants in the study who engaged in moderate-to-vigorous physical activity performed better on fluid tasks, suggesting that exercise might stave off some of the typical effects of brain aging.

However, most participants in the study did not spend a significant amount of time in physical activity; in fact, data showed that, on average, most participants spent less than 2.7% of their time engaged in moderate-to-vigorous activities. Those older adults who instead sat more hours each day performed better on knowledge-based activities, like vocabulary tests or reading comprehension. These "crystallized" abilities tend to strengthen with age as adults acquire more knowledge and experience.

Interestingly, the researchers observed no associations between light physical activities -- such as doing laundry, cooking, or other household chores -- and cognition. Although replacing sedentariness with light physical activity has been recommended for better metabolic health, there is no evidence of such a relationship at the cognitive level.

While the results are purely correlations and have no clear causes, the researchers speculate that when people are sedentary, they're likely to be engaging in educational, stimulating activities, like reading, playing games or puzzles, or attending plays, which might serve to boost crystallized cognition.

"There's this big push within health and wellness that sitting is always bad for your body, that being a couch potato is not good," Burzynska said, "and although our earlier studies indicated that the brains of those who spend more time sitting may age faster, it seems that on the cognitive level, sitting time may also be meaningful."

WAYS TO SPEND OUR SITTING TIME

However, future studies are needed to determine how exactly the participants spent their time sitting before any definitive conclusions can be made about sedentary activity and cognitive health.

Burzynska says the study reinforces the recommendation that regular exercise is good for general health, but for those older adults who might not be able to be physically active, engaging in more cognitively demanding activities may also be an option.

"I don't think I would in any way suggest that we should engage in more sitting, but I think trying to be as physically active as possible and making sure that you get stimulated in your sedentary time -- that it's not just spent staring at the TV -- that this combination might be the best way to take care of your brain," she said. "I hope it sends some positive message for those of us who have had limited opportunities to exercise during the pandemic."

In the quest for long-term brain health, it seems balance is the answer.

"When you exercise, enjoy your exercise. Maybe sometimes think, 'Yeah I'm going to go sit now and enjoy a really good book," Burzynska added.

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The Department of Human Development and Family Studies is part of CSU's College of Health and Human Sciences. Burzynska is also an affiliate faculty member in the Columbine Health Systems Center for Healthy Aging at CSU.

 

The future of krill

Experts recommend new management strategies to protect ecologically important krill in the Southern Ocean from overfishing

ALFRED WEGENER INSTITUTE, HELMHOLTZ CENTRE FOR POLAR AND MARINE RESEARCH

Research News

 

Krill is rapidly gaining popularity. The small shrimp-like organism from the Antarctic is used as fish food in aquaculture and increasingly in dietary supplements and healing ointments. Although the krill catch is regulated, caution is required to avoid endangering the population itself and the species that depend on it, warns a group of krill experts headed by Prof. Dr. Bettina Meyer from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) in the journal Communications Earth & Environment - Nature.

Antarctic Krill, Euphausia superba, is a five-centimetre-long, reddish, shrimp-like animal which at first glance, may not appear as an impressive inhabitant of the Southern Ocean. But krill make up for their small individual sizes with the sheer number of their entire population. There is an estimated 300-500 billion Mt of krill in the Southern Ocean comprised of some hundreds of trillions of individuals. This massive biomass makes krill a key component of the local ecosystem. It is the main food source for many predators from fish, penguins and seabirds to seals and whales.

Humans have also developed an interest in krill over the past decades. Norway, along with Korea, China, Chile, the Ukraine and Japan trawl for krill in the Southern Ocean. But the fishing industry has become more efficient at catching krill using not only traditional fishing nets, but new continuous pumping systems. The demand for krill will likely increase, driven by at least two industries. First the increasing production of carnivorous fish through aquaculture, such as salmon, and the subsequent increase in demand for fish meals and marine byproducts. Second, the increasing demand for high value pharma- and nutraceutical products from krill oil and krill meals, such as wound ointment and krill oil capsules for human use and pet food.

The krill fishery is managed by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), which was founded in 1982. This body uses surveys and model calculations to determine how much krill may be caught and where it may be caught. The Atlantic sector of the Southern Ocean has the highest concentration of both krill stocks and fishing fleets. This region alone has a maximum allowable catch of 620,000 tons per year distributed over different fishing areas.

This is only a fraction of krill that are estimated to live in the ocean around Antarctica. CCAMLR had long assumed that the established catch limits would not cause serious damage, but krill experts like Bettina Meyer now see things differently. "The problem is that the catch regulations have, so far, been aimed primarily at protecting the krill eaters," explains the researcher. "Too little attention, has been paid to possible risks for the krill stocks themselves.

This is due to the fact that relatively little is still known about some aspects of the biology of these small crustaceans." Financed by the Federal Ministry of Food and Agriculture (BMEL), Bettina Meyer, her colleague Dr. Ryan Driscoll and her research group are trying to shed more light on this issue. In a new publication, krill experts from around the globe summarize why there are several reasons to worry about the future of this key species.

In brief, krill abundances in some regions fluctuate greatly from year to year. However, the causes of these fluctuations are not yet clear and the current management of krill does not adjust the catch accordingly. Furthermore, it is likely that only a small part of the population, limited to a relatively small area, provide the offspring for the entire Atlantic part of the Southern Ocean. Finally, little is known about where the new generation migrate to in their first year. This means that it is possible that the most important parts of the population, the future parents and their offspring, will be overfished.

In 2019 CCAMLR decided to develop a new krill management system to address these issues. The committee is advised by the "Krill Action Group" under the umbrella of the Scientific Committee of Antarctic Research (SCAR), which was founded in 2018. It currently consists of 46 international members, half of which are established and half early career scientist. "Our goal is to provide CCAMLR with the latest knowledge on the size, distribution and dynamics of krill stocks." explains Bettina Meyer, who heads this expert group.

The future of krill management will require answering lingering question in key areas of krill biology. For example, understanding how krill populations in different regions are connected and how adults and juveniles differ in their location and movement. Also unknown are the environmental conditions responsible for determining good or bad krill years. The Atlantic sector of the Southern Ocean is warming rapidly and so understanding how krill will adapt to climate change is crucial. As for the latter, "CCAMLR's previous models do not take this plasticity into account," explains Bettina Meyer, "But we need to know more about this if we are to be able to predict future changes in the ecosystem."

Bettina Meyer and her colleagues have some concrete ideas about how the missing data can be collected. Since space and availability for scientific expeditions aboard research ships are limited, scientists could rely on the support of the fishing fleets. Together, these fishing vessels have the potential to collect a substantial amount of krill data which can help close critical knowledge gaps.

In addition, new technology may help scientists advance their understanding of krill stocks and their distribution. For example, autonomous underwater gliders, which look like mini gliders with a wingspan of about 1.50 metres, can be equipped with cameras, sensors, and echosounders to search for krill. They can roam the ocean from the surface down to 1000 metres for several months, collecting data on the density and distribution of krill.

Another promising technology are advanced moorings, equipped with arrays of sensors to measure water properties and krill density. These stationary devices can provide important information almost year-round in areas critical to the management of the krill fishery. Even krill predators, the whales, seals or penguins, can be recruited to help using attached camera systems and probes equipped with GPS.

"All of this can provide us with valuable new information for better krill management," says Bettina Meyer who is convinced by this approach. But in order to cover large areas of the Southern Ocean it is important to coordinate these research efforts internationally: "As a lone warrior, nobody can answer the complex questions of krill research."

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Original publication:

Bettina Meyer et al.: „ Successful ecosystem-based management of Antarctic krill should address uncertainties in krill recruitment, behaviour and ecological adaptation". Communications Earth & Environment - Nature, DOI 10.1038/s43247-020-00026-1

World's greatest mass extinction triggered switch to warm-bloodedness

UNIVERSITY OF BRISTOL

Research News

IMAGE: THE ORIGIN OF ENDOTHERMY IN SYNAPSIDS, INCLUDING THE ANCESTORS OF MAMMALS. THE DIAGRAM SHOWS THE EVOLUTION OF MAIN GROUPS THROUGH THE TRIASSIC, AND THE SCALE FROM BLUE TO RED IS... view more 

CREDIT: CREDIT: MIKE BENTON, UNIVERSITY OF BRISTOL. ANIMAL IMAGES ARE BY NOBU TAMURA, WIKIMEDIA.

Mammals and birds today are warm-blooded, and this is often taken as the reason for their great success.

University of Bristol palaeontologist Professor Mike Benton, identifies in the journal Gondwana Research that the ancestors of both mammals and birds became warm-blooded at the same time, some 250 million years ago, in the time when life was recovering from the greatest mass extinction of all time.

The Permian-Triassic mass extinction killed as much as 95 per cent of life, and the very few survivors faced a turbulent world, repeatedly hit by global warming and ocean acidification crises. Two main groups of tetrapods survived, the synapsids and archosaurs, including ancestors of mammals and birds respectively.

Palaeontologists had identified indications of warm-bloodedness, or technically endothermy, in these Triassic survivors, including evidence for a diaphragm and possible whiskers in the synapsids.

More recently, similar evidence for early origin of feathers in dinosaur and bird ancestors has come to light. In both synapsids and archosaurs of the Triassic, the bone structure shows characteristics of warm-bloodedness. The evidence that mammal ancestors had hair from the beginning of the Triassic has been suspected for a long time, but the suggestion that archosaurs had feathers from 250 million years ago is new.

But a strong hint for this sudden origin of warm-bloodedness in both synapsids and archosaurs at exactly the time of the Permian-Triassic mass extinction was found in 2009. Tai Kubo, then a student studying the Masters in Palaeobiology degree at Bristol and Professor Benton identified that all medium-sized and large tetrapods switched from sprawling to erect posture right at the Permian-Triassic boundary.

Their study was based on fossilised footprints. They looked at a sample of hundreds of fossil trackways, and Kubo and Benton were surprised to see the posture shift happened instantly, not strung out over tens of millions of years, as had been suggested. It also happened in all groups, not just the mammal ancestors or bird ancestors.

Professor Benton said: "Modern amphibians and reptiles are sprawlers, holding their limbs partly sideways.

"Birds and mammals have erect postures, with the limbs immediately below their bodies. This allows them to run faster, and especially further. There are great advantages in erect posture and warm-bloodedness, but the cost is that endotherms have to eat much more than cold-blooded animals just to fuel their inner temperature control."

The evidence from posture change and from early origin of hair and feathers, all happening at the same time, suggested this was the beginning of a kind of 'arms race'. In ecology, arms races occur when predators and prey have to compete with each other, and where there may be an escalation of adaptations. The lion evolves to run faster, but the wildebeest also evolves to run faster or twist and turn to escape.

Something like this happened in the Triassic, from 250 to 200 million years ago. Today, warm-blooded animals can live all over the Earth, even in cold areas, and they remain active at night. They also show intensive parental care, feeding their babies and teaching them complex and smart behaviour. These adaptations gave birds and mammals the edge over amphibians and reptiles and in the present cool world allowed them to dominate in more parts of the world.

Professor Benton added: "The Triassic was a remarkable time in the history of life on Earth. You see birds and mammals everywhere on land today, whereas amphibians and reptiles are often quite hidden.

"This revolution in ecosystems was triggered by the independent origins of endothermy in birds and mammals, but until recently we didn't realise that these two events might have been coordinated.

"That happened because only a tiny number of species survived the Permian-Triassic mass extinction - who survived depended on intense competition in a tough world. Because a few of the survivors were already endothermic in a primitive way, all the others had to become endothermic to survive in the new fast-paced world."

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Paper:

'The origin of endothermy in synapsids and archosaurs and arms races in the Triassic' by M. J. Benton in Gondwana Research

 

Energy System 2050: solutions for the energy transition

Research initiative of the Helmholtz Association presents strategies, technologies, and open-source tools

KARLSRUHER INSTITUT FÜR TECHNOLOGIE (KIT)

Research News

 

IMAGE: ENERGY SYSTEM 2050 " IS AN INITIATIVE OF THE RESEARCH FIELD ENERGY OF THE HELMHOLTZ ASSOCIATION AIMED AT DEVELOPING TANGIBLE AND USABLE FINDINGS AND TECHNICAL SOLUTIONS. view more 

CREDIT: PASCAL ARMBRUSTER, KIT

To contribute to global climate protection, Germany has to rapidly and comprehensively minimize the use of fossil energy sources and to transform the energy system accordingly. The Helmholtz Association's research initiative "Energy System 2050" has studied how and by which means this can be achieved. One of the partners is Karlsruhe Institute of Technology (KIT). At the final conference in Berlin, scientists of the participating research centers presented their results.

Having decided to achieve climate neutrality by 2050, Germany as an industrialized country is facing a tremendous challenge: Organizing a comprehensive and sustainable transformation of the energy system while ensuring stable energy supply for our everyday life, for industry, and for the operation of central communication and transport infrastructures. Within the framework of the research initiative "Energy System 2050" (ES2050), scientists of the Helmholtz Association have developed concrete strategies and technical approaches to both improving climate protection and enhancing supply security. These have already been picked up by politics and industry.

"Climate-friendly transformation of the energy system requires adequate technologies and clear systemic solutions. Within 'Energy System 2050,' we have not only succeeded in developing them. We have also tested them in real operation and elaborated flexible strategies for their use," says Professor Holger Hanselka, coordinator of the research initiative, Research Field Coordinator Energy of the Helmholtz Association, and President of KIT. "Our research initiative pools the competencies of eight research centers to make the energy transition a success."

Professor Otmar D. Wiestler, President of the Helmholtz Association, says: "Local, national, and international energy systems have to be switched to renewable energy sources as quickly as possible. This not only is an important step to cope with climate change and increasing degradation of the environment. With the help of regenerative energy systems, we can also produce energy at low costs without being dependent on imports. The 'Energy System 2050' initiative clearly shows which fundamental contributions can be made by the Helmholtz Association in line with its mission to conduct cutting-edge research for solving grand challenges facing society."

Strategies, Technologies, and Open-source Tools for the Energy Transition

The research initiative was launched in 2015 to make a relevant and forward-looking contribution to the transformation of the energy system. 170 scientists conducted research in teams that focused on a piece of the energy transition puzzle each. Based on a systemic analysis of the German energy supply system, they developed economically efficient and climate-friendly transformation paths until 2050. This work was complemented by research into the architecture and security of the future power grid and integration of hydrogen and biogenic energy sources in the energy system. Moreover, power grid components, such as redox flow storage systems, biogas facilities, or gas turbines for the reconversion of synthesis gas and biogas were subjects of studies. Researchers tested the technologies in detail and systemically analyzed their interaction. As a result, the best "team players" for sector coupling were found, including technologies to combine heat and power supply. In addition, lifecycle-oriented sustainability analyses were made. Apart from costs and CO2 emissions, such analyses consider other ecological and social factors when producing fuel from biogenic residues, for instance.

To carry out dynamic experiments on the system level, the researchers of ES2050 established a large-scale network of research infrastructures, including the Energy Lab 2.0 on the campus of KIT and the Living Lab Energy Campus of Forschungszentrum Jülich (FZJ). These detailed models of the energy system have meanwhile been equipped with own grid infrastructures and power-to-x facilities, residential buildings, and transport system components. The physical models are closely interlinked with virtual structures for the smart extension of the energy system. With the help of "digital twins," it is possible to integrate system components in experiments, although they do not yet exist - for instance, the future hydrogen infrastructure. The research initiative understands its modeling tools, datasets, and benchmarks as parts of an open ecosystem and makes them available as open sources. This "toolkit for the energy transition" is used by large transmission grid operators already.

Sustainable Contribution to the Energy Transition

It is still a long way to go to climate neutrality in the energy sector, but change has started: In 2019, for instance, the share of renewable energy sources in gross power consumption was 42.1 percent, in the year before 37.8 percent, according to the Federal Environment Agency. The results of the research initiative "Energy System 2050" can enhance this dynamic trend and extend it to cover the housing, transport, and industry sectors. The research initiative "Energy System 2050" was launched by the research field Energy of the Helmholtz Association. The partners are the KIT, the German Aerospace Center (DLR), Forschungszentrum Jülich (FZJ), the Helmholtz Centre Potsdam (GFZ), the Helmholtz Centre Berlin (HZB), the Helmholtz Centre Dresden-Rossendorf (HZDR), the Max Planck Institute for Plasma Physics (IPP - associated), and the Helmholtz Centre for Environmental Research (UFZ).

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More Information:
https://www.helmholtz.de/en/research/energy/energy_system_2050/

More about the KIT Energy Center:
http://www.energy.kit.edu

Press contact:
Dr. Martin Heidelberger
Press Officer
Phone: +49 721 608-41169
Email: martin.heidelberger@kit.edu

Being "The Research University in the Helmholtz Association", KIT creates and imparts knowledge for the society and the environment. It is the objective to make significant contributions to the global challenges in the fields of energy, mobility, and information. For this, about 9,300 employees cooperate in a broad range of disciplines in natural sciences, engineering sciences, economics, and the humanities and social sciences. KIT prepares its 24,400 students for responsible tasks in society, industry, and science by offering research-based study programs. Innovation efforts at KIT build a bridge between important scientific findings and their application for the benefit of society, economic prosperity, and the preservation of our natural basis of life. KIT is one of the German universities of excellence.

 

Long-term data show a recent acceleration in chemical and physical changes in the ocean

Two open-ocean hydrographic stations record 40 years of change in the subtropical North Atlantic Ocean

BERMUDA INSTITUTE OF OCEAN SCIENCES

Research News

 

IMAGE: FROM L TO R: ROD JOHNSON (BATS CO-PI), EMILY DAVEY (RESEARCH TECHNICIAN), DOM SMITH (RESEARCH TECHNICIAN) AND CLAIRE MEDLEY (RESEARCH TECHNICIAN) SAMPLE THE CTD FOR DISSOLVED O2 AND CO2 ABOARD... view more 

CREDIT: ELLA CEDARHOLD, BERMUDA INSTITUTE OF OCEAN SCIENCES

New research published in Nature Communications Earth & Environment uses data from two sustained open-ocean hydrographic stations in the North Atlantic Ocean near Bermuda to demonstrate recent changes in ocean physics and chemistry since the 1980s. The study shows decadal variability and recent acceleration of surface warming, salinification, deoxygenation, and changes in carbon dioxide (CO2)-carbonate chemistry that drives ocean acidification.

The study utilized datasets from Hydrostation 'S' and the Bermuda Atlantic Time-series Study (BATS) projects at the Bermuda Institute of Ocean Sciences (BIOS). Both are led by Professor Nicholas Bates, BIOS senior scientist and the projects' principal investigator (PI), and Rod Johnson, BIOS assistant scientist and the projects' co-PI. Together, these time-series represent the two longest continuous records of data from the global open ocean.

"The four decades of data from BATS and Hydrostation 'S' show that the ocean is not changing uniformly over time and that the ocean carbon sink is not stable over recent time with variability from decade to decade," Bates said.

Of the two sites, Hydrostation 'S' is the oldest, located approximately 15 miles (25 km) southeast of Bermuda and consisting of repeat biweekly hydrographic observations of temperature, salinity, and dissolved oxygen conducted through the water column since 1954. The Bermuda Atlantic Time-series Study (BATS) site is located approximately 50 miles (80 km) southeast of Bermuda. It consists of monthly sampling of the physics, chemistry, and biology of the entire water column since 1988. The study's datasets represent more than 1381 cruises to Hydrostation 'S' from 1954 to 2020 and more than 450 cruises to BATS from 1988 to the end of 2019.

Results showed that, over the last 40 years, surface temperatures in the Sargasso Sea have increased by 0.85 +/- 0.12oC, with the summer surface temperatures rising at a higher rate than winter. Additionally, the winter (<22°C) ocean state has gotten shorter by almost a month, while the summer season (with waters warmer than 25°C) has gotten longer. During the same period, surface salinity also increased by ~0.11 +/- 0.02. Importantly, these data show evidence of decadal variability; however, during the last decade (2010-2019), rapid warming of 1.18oC and salinification of 0.14 has occurred.

The data also show a trend of dissolved oxygen (DO) decline in the Sargasso Sea since the 1980s, representing a loss of ~2% per decade. Given the ocean warming observed in the Sargasso Sea, the researchers estimate that the warming impact on DO solubility would likely have contributed to about 13% of the total decline of DO over the past nearly 40 years. The remaining deoxygenation (~87%) must have resulted from the combined effect of changes in ocean biology and physics.

The BATS and Hydrostation 'S' time-series data allow direct detection of the ocean acidification signal in the surface waters of the North Atlantic Ocean. The typical pH range of surface waters in the 1980s ranged from wintertime highs of ~8.2 to summertime lows of ~8.08-8.10, with the ocean remaining mildly alkaline at present (~7.98-8.05). The rate of pH change is ~0.0019 +/- 0.0001 year-1, which is a more negative rate than previously reported and represents a 20% increase in hydrogen ion concentration since 1983. These changes were accompanied with significant increases of dissolved inorganic carbon and CO2 and decreases in both calcite and aragonite saturation states.

"In forty years, seawater CO2-carbonate chemistry conditions are now altered beyond the seasonal chemical changes observed in the 1980s," Johnson said. "The modification of seawater CO2 -carbonate chemistry will continue with future anthropogenic CO2 emissions."

The observations off Bermuda reveal the substantial decadal variations and highlight the need for long-term data to determine trends in other ocean physical and biogeochemical properties, particularly when linking local measurements to basin-scale changes. Long-term data on ocean chemistry and physical from time-series sites such as Hydrostation 'S' and BATS provide critically needed and unparalleled observations that, when coupled with ocean-atmosphere models, allow for a more complete understanding of drivers of the global carbon cycle.

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RUDN University soil scientist: Paddy soil fertilization can help reduce greenhouse effect

RUDN UNIVERSITY

Research News

 

IMAGE: A SOIL SCIENTIST FROM RUDN UNIVERSITY DISCOVERED THE EFFECT OF FERTILIZATION ON THE ABILITY OF THE SOIL TO RETAIN CARBON. TO UNDERSTAND THIS MECHANISM, HE AND HIS TEAM STUDIED THE... view more 

CREDIT: RUDN UNIVERSITY

A soil scientist from RUDN University discovered the effect of fertilization on the ability of the soil to retain carbon. To understand this mechanism, he and his team studied the movement of organic carbon in the soil of rice paddies. The results of the study can help increase the fertility of the paddies while at the same time reducing the volume of greenhouse gases in the atmosphere. An article about the study was published in the Soil Biology and Biochemistry journal.

The main reason for global climate change is the increasing amount of carbon dioxide in the atmosphere. CO2 prevents thermal emissions from leaving our planet, and the so-called greenhouse effect occurs. Being able to absorb up to 10% of carbon dioxide from the atmosphere (which amounts to approximately 20,000 megatons of carbon in 25 years), soils could mitigate this effect. A soil scientist from RUDN University studied the mechanism of carbon retention in the soils of rice paddies that account for 40% of natural atmospheric carbon absorption in China. According to him, the ability of the soil to retain carbon depends, among other factors, on its structure and the presence of fertilizers.

"The soils of rice paddies play an important role in mitigating the consequences of global warming and contribute a lot to the retention of carbon. The most effective way to study the processes that lead to the accumulation of organic carbon in the soil is to measure the concentration of its isotopes. We used this method to find out how mineral and organic fertilizers affect carbon flows between fractions of different density in rice paddy soils," said Yakov Kuzyakov, the Head of the Center for Mathematical Modeling and Design of Sustainable Ecosystems at RUDN University.

The team studied three groups of soils with different types of fertilizers: azophoska, or nitrogen-phosphorus-potassium fertilizer, was added to the first group; the second one contained azophoska with straw, and the third--azophoska with organic supplements. The content of carbon in the soils and its movement between density fractions was determined based on the ratio of 13C and 12? isotopes. The second and the third group showed better carbon retention results: after fertilization, their carbon content grew by 69%, while the increase in the first group amounted to 30%.

The scientists also paid attention to the changes in soil structure under the influence of fertilizers and the effect of such changes on carbon retention. Fertilizers consolidate the structural elements of the soil, and the number of large soil particles (over 0.25 mm in diameter) grows. Soils of medium density showed the highest carbon retention efficiency after fertilization: the amount of accumulated carbon increased by 70% compared to unfertilized soils. Less dense soil fractions showed a 21-56% increase, and carbon retention in dust and clay grew by 24-49%.

"We confirmed that fertilizers support organic carbon retention in the soil. Knowing this, we could better understand the processes that lead to the accumulation of soil carbon in rice paddies. These agricultural ecosystems already play an important role in world food security and now can also help us combat climate change," addedYakov Kuzyakov.

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Trees prefer the big city life

Study finds that red maples were more productive in an environment with more urbanization

UNIVERSITY OF DELAWARE

Research News

A team of researchers have examined whether urban red maples - a resilient native tree known to thrive in urban environments - acclimate to environmental shifts and whether that response is impacted by the size of the city.

They found that trees in larger cities are actually healthier and more productive than those in less dense areas.

To determine how trees respond to different urban intensities, the team - which includes researchers from the University of Delaware - compared forests in Newark, Del., to those in Philadelphia, Pa. In forest fragments that make up the FRAME network in each city, data was collected to measure tree size and age, foliage nitrogen signature, nutrient and heavy metal content, and stress-responding metabolites, as well as surrounding soil conditions.

Not only were the trees acclimated to urban conditions but the red maples in the higher density Philadelphia forests were actually healthier and more productive than those surrounded by less urbanization in Newark.

"We have different levels of nitrogen deposition due to fumes from vehicle tailpipes, construction materials are adding excess calcium into forest soils, carbon dioxide levels are elevated because of population density, and we have impervious surfaces like roads and buildings that are holding heat and warming up the city in a phenomenon we call urban heat island," said Covel McDermot, a University of Delaware alumnus and co-author of the study. "Our goal was to evaluate health and stress-indicating compounds in the leaves of red maple trees that face these conditions in forests embedded in a large, heavily urbanized city versus a small, fairly urbanized city."

People usually think that urban ecosystems are nutrient deficient, but we see that these systems have higher nutrient loads that support productivity.

For example, in Philadelphia there is a lot of construction using concrete. Concrete is a substance that contains calcium, magnesium and aluminum. As construction and deconstruction happen, as they often do in cities, these materials eventually break down and become available food sources for plants. Look at your wall. It's likely made of materials containing gypsum and those will eventually end up in the soil and become bioavailable to plants.

To build barriers to stressors like excessive heat or heavy metals, trees produce stress-shielding and signaling compounds which protect the chloroplast and mitochondria from oxidative stress, allowing the tree to flourish. However, there is a tradeoff in resources for growth and development versus permanent stress defense. Philadelphia soil conditions, unlike those in Newark that experienced degradation due to past agricultural practices, were more nutrient rich so those ecosystems held enough nitrogen to allow trees to produce additional stress-responding compounds while also growing into healthier, more productive forests.

McDermot hopes that this red maple study serves as the blueprint for future research on other species commonly found in urban systems.

"This gives us insight into planting the right trees in cities," McDermot said. "We can't just focus on beautification. We need to support ecological resilience. It's about prescribed greening -- planting the right tree species, in the right place, in the right soil conditions and for the right reasons."

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Sanctuary policies protect immigrants but don't threaten public safety

Counties that limit cooperation with ICE see deportations after book-ins to county jails drop by a third, but there's no measurable effect on crime

STANFORD UNIVERSITY - IMMIGRATION POLICY LAB

Research News

 

Sanctuary policies are at the center of the debate over immigration enforcement in the interior of the country. President Trump has called those policies "deadly" and claimed that they prevent the deportation of violent criminals and increase crime.

Those claims are not true, according to a new study published in the Proceedings of the National Academy of Sciences by Stanford University researcher David Hausman, a postdoctoral fellow at Stanford's Bill Lane Center for the American West and an affiliate of Stanford's Immigration Policy Lab.

"What I found is that sanctuary policies really do protect immigrants, and they also don't do any harm to public safety," Hausman said. "In fact, the data show that sanctuary policies have no measurable effect on crime."

Using datasets from Immigration and Customs Enforcement (ICE) and the Federal Bureau of Investigation (FBI), Hausman studied the onset of sanctuary policies in 140 counties between 2010 and 2015. He found the following:

• Sanctuary policies reduced deportations after local arrests by a third.

• Sanctuary had different effects on different groups of noncitizens. For noncitizens without criminal convictions, sanctuary policies reduced these deportations by half, but for noncitizens with violent convictions, sanctuary policies had no measurable effect.

• Sanctuary policies prevented about 22,300 deportations nationwide between 2013 and 2015, including about 3,300 deportations of immigrants who had never been convicted of any crime.

• Sanctuary policies had no measurable effect on crime.

"I hope that this study brings some facts to a debate that has too often relied on assertions," Hausman said.

Delving into the Data

"Sanctuary" describes a wide range of local policies limiting cooperation with federal immigration enforcement. (Sanctuary policies have no impact on whether a person is arrested, charged, convicted, or sentenced for a criminal offense.) This study focuses on sanctuary policies' key element: prohibiting local law enforcement from complying with ICE requests that jails lock up immigrants past the date when they would normally be released.

Every time police officers make an arrest, they send the person's fingerprints to the FBI, which in turn automatically shares them with ICE. If ICE identifies the person as an immigrant eligible for deportation in its own databases, it can issue a detainer to the local jail, requesting that the jail hold the person beyond the scheduled release date. This gives ICE officers extra time to pick up the person and place him or her into deportation proceedings.

For his study, Hausman looked at 369,388 deportations between November 2008 and December 2015 that began when a noncitizen was arrested by local law enforcement. At the time when many sanctuary policies were taking effect (2014-15), this kind of deportation made up 55 percent of all deportations ICE initiated from the interior of the country. Hausman focused on 296 large counties during that period, which accounted for more than 80 percent of all deportations that began with a local arrest. Of those 296 counties, 140 adopted sanctuary policies (or were affected by a state sanctuary policy) between 2010 and 2015.

Hausman then compared sanctuary and non-sanctuary counties before and after the policies were adopted. While the two groups looked roughly the same before the policies were introduced, they diverged just a few months afterward. Deportations fell by a third in sanctuary jurisdictions, but there was no decline in deportations of people with violent convictions.

In a way, it's not surprising that sanctuary policies did not protect people with violent convictions from deportation. Many sanctuary policies make exceptions for violent crimes, allowing local police to comply with ICE detainer requests for noncitizens with such convictions. And people with those convictions are more likely to serve sentences in state prisons, where ICE can easily locate them before their release.

To measure the effect of sanctuary on crime, Hausman looked at 224 large counties, narrowing the list to those that consistently reported crime data each month. Sanctuary policies appeared neither to increase crime rates nor help police solve crimes.

Taken together, these findings show that even as these policies reduce deportations, they do not harm public safety.

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Justice for all: How race and American identity may affect politics

PENN STATE

Research News

 

UNIVERSITY PARK, Pa. -- Allegiance and loyalty to your country is highly valued in America, but what if you feel America doesn't love you back? New research examined whether feeling like you belong in America -- or not -- affected how members of different races and ethnicities participated in politics.

Ray Block Jr., associate professor of political science and African American studies at Penn State, said the study suggests that people who don't embody a typical white American identity may have complicated feelings of Americanness that may also affect their politics.

"We were able to get clues about how feelings of allegiance and belonging work together to affect how a person engages politically, for example by showing up to vote or by protesting," Block said. "Allegiance and belonging can mix together in meaningful ways to influence how much people are involved in a system that they feel they either belong to or which they feel might not love them back."

According to the researchers, the study -- recently published in the National Review of Black Politics -- was partially inspired by the current state of American politics and is important because a true democracy is based on everyone's voices being heard, not just those in majority demographics.

Block said that with debates surging about the separation of immigrant families, police brutality against Black Americans and other people of color, and a rise in white nationalism, he and the other researchers wanted to examine whether those in ethnic or racial minorities might have complicated feelings about their identity in America.

"We started with the idea that certain groups of Americans don't seem to have as much claim to Americanness as other groups do," Block said. "We noticed this in politics because sometimes people will weaponize American patriotism against outsiders. One of the ultimate ways to make someone an outsider is to question their Americanness. For example, when people questioned Colin Kaepernick taking a knee during the national anthem."

For the study, the researchers used data from the 2016 Collaborative Multiracial Post-Election Survey. The survey included 10,144 participants -- with 3,006 identifying as Asian, 3,102 as Black or African American, 3,002 as Latino/a, and 1,034 as white.

The researchers measured "Americanness" with two variables. The first was "belonging," measured by questions such as asking participants whether they felt most Americans valued their presence and whether they felt others tried to exclude them. The second was "allegiance," measured by asking how much being an American is important to them.

Finally, the researchers also looked at two forms of political participation: electoral and non-electoral. Electoral participation refers to actions such as voting and donating money to campaigns while non-electoral participation refers to actions such as signing petitions or participating in marches or protests.

"Non-electoral politics is usually the tool that those who feel voiceless use in politics," Block said. "Protesting and community activism, for example, might be what a person does when they feel outside the system. The more connected to the system you feel, the more likely you won't need non-electoral participation. But the less connected you feel you are to the system, the more appealing non-mainstream forms of political action become."

After analyzing the data, the researchers found that white respondents felt strongly that they belonged in America, while racial and ethnic minorities felt less belonging. Whites also reported higher levels of allegiance. When measuring political participation, whites reported the highest level of electoral participation.

When the researchers examined the connections between Americanness and electoral and non-electoral participation, Block said things got a little murkier. While the findings were statistically insignificant, he said the results still show patterns and clues to how feelings of allegiance and belonging may affect how someone participates politically.

For example, one pattern suggested that when a person's sense of belonging was low, allegiance had no connection to political participation. But when belonging was higher, there was the possibility that also feeling allegiance could increase a person's tendency to vote.

"This makes sense -- if electoral participation represents a very 'mainstream' type of activism, then why would anyone bother to take part in it if they do not think their society values/respects/includes them?" the researchers wrote in the paper. "Furthermore, the findings for non-electoral participation comport well with what we already know. The less highly regarded by their country people feel, the more appealing nonelectoral modes of activism become."

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Stacey Greene, Rutgers University; Gabrielle Gray, Howard University; and Niambi Michele Carter, Howard University, also participated in this work.

 

Study: More than 200 million Americans could have toxic PFAS in their drinking water

ENVIRONMENTAL WORKING GROUP

Research News

 

WASHINGTON - A peer-reviewed study by scientists at the Environmental Working Group estimates that more than 200 million Americans could have the toxic fluorinated chemicals known as PFAS in their drinking water at a concentration of 1 part per trillion, or ppt, or higher. Independent scientific studies have recommended a safe level for PFAS in drinking water of 1 ppt, a standard that is endorsed by EWG.

The study, published today in the journal Environmental Science & Technology Letters, analyzed publicly accessible drinking water testing results from the Environmental Protection Agency and U.S. Geological Survey, as well as state testing by Colorado, Kentucky, Michigan, New Hampshire, New Jersey, North Carolina and Rhode Island.

"We know drinking water is a major source of exposure of these toxic chemicals," said Olga Naidenko, Ph.D., vice president for science investigations at EWG and a co-author of the new study. "This new paper shows that PFAS pollution is affecting even more Americans than we previously estimated. PFAS are likely detectable in all major water supplies in the U.S., almost certainly in all that use surface water."

The analysis also included laboratory tests commissioned by EWG that found PFAS chemicals in the drinking water of dozens of U.S. cities. Some of the highest PFAS levels detected were in samples from major metropolitan areas, including Miami, Philadelphia, New Orleans and the northern New Jersey suburbs of New York City.

There is no national requirement for ongoing testing and no national drinking water standard for any PFAS in drinking water. The EPA has issued an inadequate lifetime health advisory level of 70 ppt for the two most notorious fluorinated chemicals, PFOA and PFOS, and efforts to set an enforceable standard could take many years.

In the absence of a federal standard, states have started to pass their own legal limits for some PFAS. New Jersey was the first to issue a maximum contaminant limit for the compound PFNA, at 13 ppt, and has set standards of 13 ppt for PFOS and 14 ppt for PFOA. Many states have either set or proposed limits for PFOA and PFOS, including California, Massachusetts, Michigan, New Hampshire, New Jersey, New York and Vermont.

"The first step in fighting any contamination crisis is to turn off the tap," said Scott Faber, EWG senior vice president for government affairs. "The second step is to set a drinking water standard, and the third is to clean up legacy pollution. The PFAS Action Act passed by the House would address all three steps by setting deadlines for limiting industrial PFAS releases, setting a two-year deadline for a drinking water standard, and designating PFAS as 'hazardous substances' under the Superfund law. But Mitch McConnell's Senate has refused to act to protect our communities from 'forever chemicals.'"

PFAS are called forever chemicals because they are among the most persistent toxic compounds in existence, contaminating everything from drinking water to food, food packaging and personal care products. They are found in the blood of virtually everyone on Earth, including newborn babies. They never break down in the environment.

Very low doses of PFAS chemicals in drinking water have been linked to suppression of the immune system and are associated with an elevated risk of cancer and reproductive and developmental harms, among other serious health concerns.

"When we look for PFAS contamination, we almost always find it," said David Andrews, Ph.D., a senior scientist at EWG and one of the co-authors. "Americans should trust that their water is safe, but far too many communities have water supplies polluted by toxic PFAS chemicals. These are some of the most insidious chemicals ever produced, and they continue to be used. Our analysis was largely limited to PFOA and PFOS, but many more PFAS are found to contaminate drinking water and the entire class of PFAS chemicals is a concern."

The EPA has identified over 600 PFAS in active use in the U.S. According to the most recent analysis of state and federal data by EWG, 2,230 locations in 49 states are known to have PFAS contamination, including more than 300 military installations.

PFAS contamination has raised alarms among a bipartisan group of lawmakers in Congress. The PFAS Action Act also includes a provision that would set a two-year deadline for the EPA to establish a national drinking water standard for the two most notorious PFAS chemicals - PFOA, formerly used to make DuPont's Teflon, and PFOS, formerly an ingredient in 3M's Scotchgard.

The House versions of the National Defense Authorization Act and EPA spending bill also include important PFAS reforms.

"It's not too late for this Congress to protect us from the growing PFAS contamination crisis," Faber said.

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The Environmental Working Group is a nonprofit, non-partisan organization that empowers people to live healthier lives in a healthier environment. Through research, advocacy and unique education tools, EWG drives consumer choice and civic action.