FOREVER CHEMICALS
Newer PFAS compound detected for first time in Arctic seawaterby American Chemical Society
Aboard an icebreaker ship, researchers collected water samples flowing into and out of the Arctic Ocean and analyzed them for PFAS. Credit: Hanna Joerss

Per- and polyfluoroalkyl substances (PFAS), found in many household products and food packages, have raised concerns because of their persistence and possible toxicity to people and wildlife. Because the compounds don't break down naturally, they have become environmental contaminants. Now, researchers reporting in Environmental Science & Technology have studied the transport of 29 PFAS into and out of the Arctic Ocean, detecting a newer compound for the first time in Arctic seawater.


After studies indicated that two PFAS—PFOA and PFOS—can cause cancer, a compromised immune response and other health problems in lab animals, the two compounds were voluntarily phased out by industry. However, these legacy compounds are still widely detected in the environment. Intended as a safer replacement for PFOA, HFPO-DA (sold under the trade name GenX) is now thought to pose similar health and persistence concerns. Hanna Joerss and colleagues wanted to investigate the long-range, oceanic transport of legacy and replacement PFAS to the Arctic Ocean—a remote body of water connected to the Atlantic Ocean by the Fram Strait, which is located between Svalbard and Greenland.

Aboard an icebreaker research ship, the team collected water samples along two Fram Strait currents entering and exiting the Arctic Ocean and along a path from Europe's North Sea to the Arctic Ocean. Using mass spectrometry, the researchers detected 11 PFAS in the ocean water, including PFOA, HFPO-DA and other long- and short-chain PFAS. This was the first time that HFPO-DA had been detected in seawater from a remote region, indicating that the compound can be transported long distances. Higher levels of PFAS were detected in the water exiting the Arctic Ocean compared with the water entering the Arctic from the North Atlantic. The PFAS composition in the outgoing water suggested that more of these compounds arose from atmospheric sources than from ocean circulation.


Explore furtherWinds spread PFAS pollution far from a manufacturing facility

More information: "Transport of Legacy Perfluoroalkyl Substances and the Replacement Compound HFPO-DA through the Atlantic Gateway to the Arctic Ocean—Is the Arctic a Sink or a Source?" Environmental Science & Technology (2020). pubs.acs.org/doi/abs/10.1021/acs.est.0c00228

Journal information: Environmental Science & Technology


Provided by American Chemical Society

PATRIARCHY
New research finds crises such as COVID-19 pandemic threaten support for Title IX

by University of Massachusetts Amherst

Credit: CC0 Public Domain

A new study by a pair of researchers including Elizabeth Sharrow, associate professor of public policy and history at the University of Massachusetts Amherst, has found that male student-athletes and those with sexist attitudes exhibit "alarmingly" low levels of support for ensuring the maintenance of equality and sexual harassment policy under Title IX as a result of the COVID-19 crisis and its impact on college athletics.
In the report, published online by the journal Politics & Gender, Sharrow and co-author James Druckman of Northwestern University write that the results accentuate the vulnerability of certain populations during crises, and the importance of maintaining strong institutional policy support during such times.

Sharrow and Druckman conducted a survey with a representative sample of 1,925 student-athletes in May and June. They found middling levels of support for protecting equality and sexual harassment provisions when respondents were asked about each specifically during the COVID-19 pandemic, with respective mean scores notably lower than those found when respondents were asked about their general support of the provisions earlier in the survey.

"This COVID-19 study arose from a multi-year research project in which my collaborator and I are studying attitudes toward gender equity policies and pay-for-play policies among stakeholders in American collegiate athletics," Sharrow says. "Our previous scholarship found that Title IX of the Education Amendments of 1972 enjoys high levels of support among the beneficiaries of policy in college sport, as well as the American public, but we suspected that times of crisis can undermine popular support for protective policies, particularly among those who don't directly benefit from policy protections.

"The COVID-19 pandemic has rapidly transformed college athletics since March with many institutions canceling funding for selected teams due to financial strain," she continues. "We wondered whether Title IX's protections continue to receive high-levels of support as the crisis unfolds, and found that male college athletes and those with high sexist attitudes exhibit decidedly low levels of support for Title IX and sexual harassment protections during the COVID-19 crisis."

The researchers found notable differences by gender—specifically a 20.75% decrease in support from women to men when it comes to protecting equality during COVID-19, and a 14.75% decrease in support from women to men for safeguarding anti-harassment protections.

The findings accentuate the importance of maintaining strong institutional policy support for the enforcement of non-discrimination policies, says Sharrow, an expert on the politics of Title IX and the ways that public policy shapes understandings of sex and gender at the intersections of race, sexuality, ability and class.

"We demonstrate why beneficiaries need strong legal safeguards and enforcement of gender equality policies so that protections are not undermined when systems are under stress and/or lack support from advantaged, majority stakeholders," she says. "Even despite Title IX's implementation, men remain the majority of college athletes. We illustrate that post-crisis recovery efforts will require close oversight on protections for vulnerable groups, irrespective of whether such groups are in a position to advocate on their own behalf. The future for further incorporation of historically-marginalized groups, and the maintenance of hard-won opportunities for women and girls in sport in particular, will depend on it."


Explore further New report sheds light on the impact of COVID-19 on gender and sustainability

More information: James N. Druckman et al. Public Opinion, Crisis, and Vulnerable Populations: The Case of Title IX and COVID-19, Politics & Gender (2020). DOI: 10.1017/S1743923X20000446 

Provided by University of Massachusetts Amherst

It pays to major in fields with close ties to jobs, study shows

by Amy McCaig, Rice University

College graduates make more money if they major in fields with close ties to jobs, according to a new study from the Houston Education Research Consortium (HERC), part of Rice University's Kinder Institute for Urban Research and School of Social Sciences.

"School-to-Work Linkages in Texas," authored by HERC researchers Brian Holzman and Bethany Lewis and graduate student Irina Chukhray of the University of California, Davis, examines Texas residents with bachelor's degrees who are 25-64 years old using microdata from the American Community Survey 5-Year Sample for 2013-2017.

The researchers studied what they refer to as "linkage," the connection between college majors and specific occupations. Some college majors like architecture and engineering have clear paths to jobs, while other majors like history and social science do not and end up working in a variety of professions ranging from teaching to business. Holzman, Lewis and Chukhray found that graduates who completed college majors with clearer paths to jobs not only tended to make more money, but also were less likely to find themselves unemployed.

"Aside from the positive relationship between linkage and earnings, we also found linkage mattered more for women, Black, Hispanic, foreign-born and non-native-English-speaking workers," Holzman said. "Linkage appeared to close wage gaps between marginalized and privileged populations."
The report also found:
People who completed college majors with weak ties to jobs (such as graduates with degrees in history and social sciences) had a 3.2% likelihood of being unemployed, compared with 2.4% for those who completed majors with strong ties to jobs (such as graduates working in professions like architecture and engineering).
Older, female, Asian, foreign-born and non-native-English-speaking workers were more likely to choose college majors with closer ties to jobs than those who were younger, male, white, Black, Hispanic, native-born or native English speakers.

Holzman and his co-authors recommend education policymakers and researchers explore why students choose college majors strongly or loosely connected to the job market. The researchers also suggest higher-education practitioners develop new strategies to help students understand the career pathways open to them when choosing a given major. Finally, they recommend college career placement and academic staff collaborate with employers to help students, particularly those from underserved backgrounds, find jobs in occupations related to their majors.


Explore furtherAttendance, grades, advanced courses best predict if HISD students will go to college
More information: The paper is available online at kinder.rice.edu/
Provided by Rice University
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The future of work is flexible, says new study

WE HAVE BECOME HUMAN CAPITAL NOT ONLY IS OUR PRODUCTIVE VALUE STOLEN FROM US WE PAY TO HAVE IT DONE TO US 

THE DIFFERENCE BETWEEN FREE TIME AND WORK TIME IN POSTMODERN CAPITALISM IS THAT I GET PAID FOR MY WORK TIME.

by Hasan Salim Patel, University of Birmingham

Credit: CC0 Public Domain

New research from the University of Kent and the University of Birmingham has found that mass homeworking during the COVID-19 lockdown has presented significant challenges for parents, particularly mothers, but has also changed the way that many people intend to work in the future.


The Working from Home during COVID-19 Lockdown Project, led by Dr. Heejung Chung of Kent's School of Social Policy, Sociology and Social Research, and Dr. Holly Birkett and Dr. Sarah Forbes of Birmingham Business School, has highlighted a steep rise in the number of employees working flexibly with 86% of those surveyed working from home at some point during the COVID-19 lockdown.

The research indicates that attitudes to flexible working are changing as a result of lockdown. Most respondents noted they would prefer to work more flexibly in the future (including 52% of all parents and 66% of non-parents), after benefitting from a better work-life balance, increased productivity and improved wellbeing during lockdown. Parents predominantly wanted more flexibility and to reduce their working hours with 64% of fathers and 59% of mothers saying they would like to reduce their hours to spend more time with family.

Managers and organizations have also improved their support for homeworking during lockdown. 90% of those who worked from home during lockdown said their manager was supportive of the arrangement and 72.7% noted that their manager really cares about the effect that work demands have on their personal and family life. Employers have also improved the tools and support available to homeworkers during lockdown with 41% noting they had appropriate tools for homeworking pre-lockdown rising to 62% during lockdown.

The research also highlights some negative experiences of home working during lockdown, with two thirds of employees struggling to cope with the blurred boundaries between work and home. Many respondents (26% of the sample) particularly non-parents (41% of non-parents vs 21% of parents), missed interaction with colleagues. Lockdown has also had a disproportionately negative impact on parents, especially mothers, with a majority noting that they have been carrying out more housework and care, as well as educating their children during the lockdown period. As a result, 48% of mothers in the survey said they had felt rushed or pressed more than half the time during lockdown. Many parents have had to cut down their working hours during lockdown by as much as 22%. Only 50% of mothers and 58% of fathers said they could secure a stable block of time in which to work during lockdown. However, more positively 36% of all respondents did report being more productive while working from home during lockdown.


The research does also find that fathers have become more involved in childcare and unpaid work at home during lockdown particularly those who took more than the two weeks statutory paternity leave when their child was born or adopted. This suggests that parents might have established new patterns of gendered care and unpaid work in the home during lockdown, which could potentially influence behaviors and wider cultural norms around care and housework in the future.

Dr. Chung said: "Many employees would have found themselves working from home for the first time during the COVID-19 lockdown, or at least in very different circumstances to what they are used to. Our research has brought to light the variety of experiences had, both positive and negative. We have seen a reduction in negative perception towards those working flexibly, and this is certainly a step in the right direction. However, it is clear that parents in particular need more support during school and childcare closures. There are signs that the increased workload and conflict between work and family has negatively impacted parents' mental wellbeing, especially mothers. We need a thorough gendered analysis on the economic impact of the lockdown and more resources and policies are needed to support parents especially mothers' labor market attachments."

Dr. Birkett said: "Large scale working from home during the COVID-19 lockdown has the potential to significantly impact the future of work in the UK and across the globe. Many employees and employers have had their first taste of home working and our research shows that both groups have seen the advantages of more flexible working. Our research also shows that employers have improved their systems and support for flexible working during lockdown and following this home working experience the majority of employees see flexible working as a way to improve their work-life balance in the future."


Explore furtherThe parenting myth revealed by lockdown
More information: Working from home during the COVID-19 lockdown: Changing preferences and the future of work. drive.google.com/file/d/1Ooyxk … Ld14fVI8Hl7xRGe/view
Provided by University of Birmingham

#CTHULHU STUDIES

First gene knockout in cephalopod achieved 

CRISPR CRITTERS

by Marine Biological Laboratory

Longfin inshore squid (Doryteuthis pealeii) hatchlings. On the left is a control hatchling; note the black and reddish brown chromatophores evenly placed across its mantle, head and tentacles. In contrast, the embryo on the right was injected with CRISPR-Cas9 targeting a pigmentation gene (Tryptophan 2,3 Dioxygenase) before the first cell division ; it has very few pigmented chromatophores and light pink to red eyes. Credit: Karen Crawford

A team at the Marine Biological Laboratory (MBL) has achieved the first gene knockout in a cephalopod using the squid Doryteuthis pealeii, an exceptionally important research organism in biology for nearly a century. The milestone study, led by MBL Senior Scientist Joshua Rosenthal and MBL Whitman Scientist Karen Crawford, is reported in the July 30 issue of Current Biology.


The team used CRISPR-Cas9 genome editing to knock out a pigmentation gene in squid embryos, which eliminated pigmentation in the eye and in skin cells (chromatophores) with high efficiency.

"This is a critical first step toward the ability to knock out—and knock in—genes in cephalopods to address a host of biological questions," Rosenthal says.

Cephalopods (squid, octopus and cuttlefish) have the largest brain of all invertebrates, a distributed nervous system capable of instantaneous camouflage and sophisticated behaviors, a unique body plan, and the ability to extensively recode their own genetic information within messenger RNA, along with other distinctive features. These open many avenues for study and have applications in a wide range of fields, from evolution and development, to medicine, robotics, materials science, and artificial intelligence.

The ability to knock out a gene to test its function is an important step in developing cephalopods as genetically tractable organisms for biological research, augmenting the handful of species that currently dominate genetic studies, such as fruit flies, zebrafish, and mice.
Doryteuthis pealeii, often called the Woods Hole squid. Studies with D. pealeii have led to major advances in neurobiology, including description of the fundamental mechanisms of neurotransmission. The Marine Biological Laboratory collects D. pealeii from local waters for an international community of researchers. Credit: Roger Hanlon

It is also a necessary step toward having the capacity to knock in genes that facilitate research, such as genes that encode fluorescent proteins that can be imaged to track neural activity or other dynamic processes.

"CRISPR-Cas9 worked really well in Doryteuthis; it was surprisingly efficient," Rosenthal says. Much more challenging was delivering the CRISPR-Cas system into the one-celled squid embryo, which is surrounded by an exceedingly tough outer layer, and then raising the embryo through hatching. The team developed micro-scissors to clip the egg's surface and a beveled quartz needle to deliver the CRISPR-Cas9 reagents through the clip.

Studies with Doryteuthis pealeii have led to foundational advances in neurobiology, beginning with description of the action potential (nerve impulse) in the 1950s, a discovery for which Alan Hodgkin and Andrew Huxley became Nobel Prize laureates in 1963. For decades D. pealeii has drawn neurobiologists from all over the world to the MBL, which collects the squid from local waters.

Recently, Rosenthal and colleagues discovered extensive recoding of mRNA in the nervous system of Doryteuthis and other cephalopods. This research is under development for potential biomedical applications, such as pain management therapy.

D. pealeii is not, however, an ideal species to develop as a genetic research organism. It's big and takes up a lot of tank space plus, more importantly, no one has been able to culture it through multiple generations in the lab.

For these reasons, the MBL Cephalopod Program's next goal is to transfer the new knockout technology to a smaller cephalopod species, Euprymna berryi (the hummingbird bobtail squid), which is relatively easy to culture to make genetic strains.


Explore furtherThe mysterious, legendary giant squid's genome is revealed
More information: Current Biology (2020). DOI: 10.1016/j.cub.2020.06.099
Journal information: Current Biology


Provided by Marine Biological Laboratory

Partnerships with bankrupt companies could be double-edged sword for investors
by Indiana University

Credit: Unsplash/CC0 Public Domain

The list of companies that have filed for bankruptcy during the first half of 2020 reads like a "who's who" of major retailers and recognized brands. Consumers may know J.C. Penney, Hertz, Neiman Marcus, J. Crew and Pier 1, but the carnage also includes tech firms previously seen to have much potential.

With the recent rise in bankruptcies, suppliers and partners of these companies are being forced to make a difficult decision: Should they bet on the bankrupt customer or partner to survive by continuing to invest in the relationship? Or should they bet that the bankrupt customer or partner will not survive by cutting off their investments so they can minimize losses and redeploy resources?

New research from the Indiana University Kelley School of Business found that when a company is in bankruptcy, its advertising and research and development investments can cut both ways. They increase the odds of surviving for some bankrupt companies and decrease the odds for others.

"This difference hinges on the influence that the bankrupt company's suppliers have in the bankruptcy process," said Niket Jindal, assistant professor of marketing and the study's author. "Advertising and R&D increase bankruptcy survival when suppliers have high influence, whereas they decrease bankruptcy survival when suppliers have low influence."

His article, "The Impact of Advertising and R&D on Bankruptcy Survival: A Double-Edged Sword," appears in the current issue of the Journal of Marketing.

Jindal studied whether a company's past investments in intangible assets—specifically investments in advertising and R&D—can help suppliers and partners make a decision on whether to bet on the bankrupt company. He analyzed 1,672 bankruptcy cases filed in U.S. bankruptcy courts from 1996 to 2019 and found that managers could substantially improve their odds of correctly predicting whether a bankrupt customer or partner will survive by considering the company's past advertising and R&D investments, in addition to the usual financial predictors.

He found that by considering a bankrupt company's advertising and R&D, managers can increase the accuracy of predicting whether that company will survive by 11 percent.

Specifically, the results show that a bankrupt company's advertising increases the odds of its survival when at least 38 percent of the company's debt has been borrowed from suppliers. For R&D, the cutoff point is when at least 21 percent of the company's debt has been borrowed from suppliers.

"A losing bet can be catastrophic for a supplier or partner," Jindal said. "If the company bets on a bankrupt customer or partner to survive and they do not survive, investments in the relationship will be lost, and the company will have fewer resources and time to try to attract other customers and partners to make up for the lost sales. On the other hand, if the company bets against the bankrupt customer or partner and they do survive, the relationship will be soured and will put future sales from them at risk."

Jindal said that suppliers and partners should be careful when including a bankrupt firm's advertising and R&D investments in their decision-making process.

"The key is to look at the portion of the bankrupt company's debt that is due to suppliers versus banks, because this shows the influence that the bankrupt company's suppliers will have, relative to other creditors, in the bankruptcy process," he said.

Suppliers have greater noncontractual revenue and generally do not require collateral, while banks have less noncontractual revenue and generally do require collateral. The impact of advertising and R&D on the value that is received if the bankrupt firm survives versus gets liquidated differs for suppliers versus banks.

Explore further Hertz allowed to sell $1 bn in shares despite bankruptcy

More information: Niket Jindal, The Impact of Advertising and R&D on Bankruptcy Survival: A Double-Edged Sword, Journal of Marketing (2020). DOI: 10.1177/0022242920936205
Journal information: Journal of Marketing

Provided by Indiana University

Legacies of historical human activities in Medieval forest dynamics of the Italian peninsula

by Gianluca Piovesan, Scott Mensing, University of Tuscia

Springs and wetland vegetation close to the Nature Reserve of Lago Lungo and Ripa Sottile Rieti. Credit: Gianluca Piovesan
When historians and paleoecologists work directly together to study the past (what is called a consilience-driven approach) we are able to develop much more nuanced explanations for the role of people (or climate) as a cause of past abrupt environmental change. The joint histories of socioeconomic change, developed from archival sources, and ecologic change, reconstructed from pollen analysis of lake sediments, has helped clarify the interrelationship between societal factors and climate forcing in shaping land-use legacies along the Italian Peninsula. We found that different communities, guided by different political and economic structures, created entirely different landscapes, even during periods of similar climate, but after the black plague the rewilding landscape is a common trait in the Apennines


Reconstructing landscape history during Medieval times in Italia peninsula

During the period of Medieval Climate, important differences were revealed in the mountain landscape of the Central Apennines in respect to the Pollino massif. Since the ninth century up to the16th century in the Rieti Basin, consolidation of small landholdings under the church led to larger-scale production of agricultural products and forest clearance. Near Pollino massif, under the same climatic regime, a deforested landscape managed using slash and burn agriculture is present up to the Norman conquest, at which point burning stops and preservation of fir forest for extraction of timbers for construction begins.

The fast recolonization of silver fir forest soon after the expansion of early succession maples and alders is a surprising and interesting process that, however, is forecasted by vegetation dynamics in the absence of human disturbance and finds an analog in today's vegetation dynamics. "This unexpected forest rewilding during the Medieval Climate Anomaly led us to suppose that the spread of fir was a consequence of the abandonment of the land and the protection of seedlings and saplings from fires and from grazing, in the same way today observed inside the strict reserves of Pollino, Sila and Aspromonte National parks," says Gianluca Piovesan from the University of Tuscia.

In both locations, following the black plague and depopulation, the forests shifted to a trajectory of secondary succession and rewilding, a trend observed across most of western Europe. However, the individual pathway of each successional pattern was strongly influenced by human activity prior to land abandonment and local environmental conditions.

Forest rewilding in the Apennines: a process that dates back to late Medieval times

This study confirmed that forest expansion in Mediterranean mountain environments is a fast process. However, following land abandonment, the return to an old-growth state takes centuries. "Considering the intense impact of Medieval society on the Apennines, we hypothesize that most old-growth forest remnants are a landscape legacy of the late Medieval rewilding phase that is still moving closer to a more complex forest ecosystem, as in the case of mountain beech forests or subalpine Heldrich's pine stands," says Gianluca Piovesan, who is coordinating Italian Mountain Lab project for Tuscia University.

Written records in the Rieti State Archive dating back to Medieval times, such as this late medieval document, were compared to pollen diagrams – constructed from cores extracted in high sedimentation lakes - to develop a detailed history of landscape change over time. Credit: University of Tuscia
The combination of paleoecologic, paleoclimatologic and archeological/historical data at the local scale provides a much more nuanced interpretation of causality for abrupt environmental change underlying the central role of human pressures in forest degradation. The demographic collapse after the black pest caused a widespread rewilding, particularly evident in the mountain environment of the central and South Apennines. By linking multiple sites across a region, we have the potential to gain a much deeper understanding of human land-use legacies on forest landscapes.


Explore furtherOld pine trees witness the rewilding in Mediterranean mountain forests in consequence of late-medieval pandemics

More information: Mensing, S., Schoolman, E.M., Palli, J. & Piovesan, G. (in press). A consilience-driven approach to land use history in relation to reconstructing forest land use legacies. Landscape Ecol (2020). DOI: 10.1007/s10980-020-01079-5

Provided by University of Tuscia

Are young trees or old forests more important for slowing climate change?
by Tom Pugh, The Conversation

Credit: Jeremy Kieran/Unsplash, CC BY-SA

Forests are thought to be crucial in the fight against climate change—and with good reason. We've known for a long time that the extra CO₂ humans are putting in the atmosphere makes trees grow faster, taking a large portion of that CO₂ back out of the atmosphere and storing it in wood and soils.


But a recent finding that the world's forests are on average getting "shorter and younger" could imply that the opposite is happening. Adding further confusion, another study recently found that young forests take up more CO₂ globally than older forests, perhaps suggesting that new trees planted today could offset our carbon sins more effectively than ancient woodland.

How does a world in which forests are getting younger and shorter fit with one where they are also growing faster and taking up more CO₂? Are old or young forests more important for slowing climate change? We can answer these questions by thinking about the lifecycle of forest patches, the proportion of them of different ages and how they all respond to a changing environment.

The forest carbon budget

Let's start by imagining the world before humans began clearing forests and burning fossil fuels.

In this world, trees that begin growing on open patches of ground grow relatively rapidly for their first several decades. The less successful trees are crowded out and die, but there's much more growth than death overall, so there is a net removal of CO₂ from the atmosphere, locked away in new wood.

As trees get large two things generally happen. One, they become more vulnerable to other causes of death, such as storms, drought or lightning. Two, they may start to run out of nutrients or get too tall to transport water efficiently. As a result, their net uptake of CO₂ slows down and can approach zero.

Eventually, our patch of trees is disturbed by some big event, like a landslide or fire, killing the trees and opening space for the whole process to start again. The carbon in the dead trees is gradually returned to the atmosphere as they decompose.

New trees absorb lots of carbon, old trees store more overall and dead trees shed their carbon to the atmosphere. Credit: Greg Rosenke/Unsplash, CC BY-SA

The vast majority of the carbon is held in the patches of big, old trees. But in this pre-industrial world, the ability of these patches to continue taking up more carbon is weak. Most of the ongoing uptake is concentrated in the younger patches and is balanced by CO₂ losses from disturbed patches. The forest is carbon neutral.


Now enter humans. The world today has a greater area of young patches of forest than we would naturally expect because historically, we have harvested forests for wood, or converted them to farmland, before allowing them to revert back to forest. Those clearances and harvests of old forests released a lot of CO₂, but when they are allowed to regrow, the resulting young and relatively short forest will continue to remove CO₂ from the atmosphere until it regains its neutral state. In effect, we forced the forest to lend some CO₂ to the atmosphere and the atmosphere will eventually repay that debt, but not a molecule more.

But adding extra CO₂ into the atmosphere, as humans have done so recklessly since the dawn of the industrial revolution, changes the total amount of capital in the system.

And the forest has been taking its share of that capital. We know from controlled experiments that higher atmospheric CO₂ levels enable trees to grow faster. The extent to which the full effect is realised in real forests varies. But computer models and observations agree that faster tree growth due to elevated CO₂ in the atmosphere is currently causing a large carbon uptake. So, more CO₂ in the atmosphere is causing both young and old patches of forest to take up CO₂, and this uptake is larger than that caused by previously felled forests regrowing.

The effect of climate change

But the implications of climate change are quite different. All else being equal, warming tends to increase the likelihood of death among trees, from drought, wildfire or insect outbreaks. This will lower the average age of trees as we move into the future. But, in this case, that younger age does not have a loan-like effect on CO₂. Those young patches of trees may take up CO₂ more strongly than the older patches they replace, but this is more than countered by the increased rate of death. The capacity of the forest to store carbon has been reduced. Rather than the forest loaning CO₂ to the atmosphere, it's been forced to make a donation.

So increased tree growth from CO₂ and increased death from warming are in competition. In the tropics at least, increased growth is still outstripping increased mortality, meaning that these forests continue to take up huge amounts of carbon. But the gap is narrowing. If that uptake continues to slow, it would mean more of our CO₂ emissions stay in the atmosphere, accelerating climate change.

Overall, both young and old forests play important roles in slowing climate change. Both are taking up CO₂, primarily because there is more CO₂ about. Young forests take up a bit more, but this is largely an accident of history. The extra carbon uptake we get from having a relatively youthful forest will diminish as that forest ages. We can plant new forests to try to generate further uptake, but space is limited.

But it's important to separate the question of uptake from that of storage. The world's big, old forests store an enormous amount of carbon, keeping it out of the atmosphere, and will continue to do so, even if their net CO₂ uptake decreases. So long as they are not cut down or burned to ashes, that is.


Explore furtherSaving Africa's biggest trees to help Earth breathe

Provided by The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.

One-quarter of native mammals now at risk of extinction in Britain


by University of Sussex

Credit: Mark Evans / The Mammal Society

The first official Red List for British Mammals, led by a University of Sussex professor, shows that 11 of the 47 mammals native to Britain are classified as being at imminent risk of extinction.
A further five species are classified as "near threatened"—meaning that there is a realistic possibility of them becoming threatened with extinction in the near future, and four are "data deficient"—meaning that their conservation status is unknown owing to a lack of information.

The Red List for Great Britain was produced by the Mammal Society for Natural England, Natural Resources Wales, Scottish Natural Heritage (NatureScot) and the Joint Nature Conservation Committee.

Crucially, it has received authorisation on behalf of the International Union for the Conservation of Nature (IUCN) at a regional level. This is significant as it means that the threatened British species have been identified using the same robust, internationally agreed system that is applied to classify threats to species such as elephants and tigers.

Fiona Mathews, Mammal Society Chair and Professor at the University of Sussex, led the report. She says: "The new Red List provides a very clear basis for prioritising funding and conservation efforts for the future. Twenty species—those classed as Threatened, Near Threatened, and Data Deficient—all need urgent attention.

"While we bemoan the demise of wildlife in other parts of the world, here in Britain we are managing to send even rodents towards extinction. Things have to change rapidly if we want our children and grandchildren to enjoy the wildlife we take for granted."

Among those species listed as being at risk of extinction in Britain are the water vole, hedgehog, hazel dormouse, wildcat and the grey long-eared bat. The European wolf is already extinct.

The reasons for the declines vary between species. For some, such as the wildcat, pine marten and beaver (which is doing well in the scattered locations where it has been reintroduced), there has been extensive historical persecution. For bats and the hazel dormouse, habitat loss is the main threat; the water vole, red squirrel and Orkney vole suffer from the combined effects of habitat degradation and the introduction of non-native species.

Natural England Chair Tony Juniper said "This is a wake-up call, but it is not too late to act. We are working with our partners to recover our threatened and widely loved mammals, including licensing the reintroduction of beavers into England, and supporting the recovery of dormice and the grey long-eared bat, but there is so much more to do.

"Central to the recovery of these and other creatures will be the protection and restoration of large areas of suitable habitat, including through the creation of a vibrant and wildlife-rich Nature Recovery Network, enabling populations of rare animals to increase and be reconnected with one another."

Reintroductions can offer hope for some species. For example, local reintroductions of beavers have been successful, with the animals readily breeding in the wild; and translocations of pine martens from Scotland—where over 98% of the British population is found—have boosted populations in Wales. Nevertheless, the animals will cease to be classed as threatened only once their populations are much larger and better connected.

Unfortunately, for most other species, reintroductions are not a solution because the causes of their declines have not been rectified. Instead, fundamental change is needed in the way we manage our landscapes and plan future developments, so that we provide the space and habitat needed for our wildlife to thrive.

Members of the public can get involved with keeping an eye on Britain's mammals using the Mammal Society's free Mammal Mapper app.


Explore further British mammals' fight for survival

Provided by University of Sussex

MURDER MOST FOUL DOWNUNDER
Some crimes have seen drastic decreases during coronavirus, but not homicides in the United States

by Terry Goldsworthy, The Conversation

Credit: Shutterstock

The various restrictions put in place to combat the spread of coronavirus in recent months have disrupted life for everyone—including criminals.

More than six months into the pandemic, it is clear the pandemic has had a major effect on crime rates. Certain crimes, such as robberies and sexual offenses, have declined dramatically, while others, such as online fraud, have been on the rise.

Of course, it is difficult to firmly establish a direct causal relationship between coronavirus restrictions and crime rates, but the statistics reveal some common themes.

Reductions in burglaries and assaults

Lockdown policies in Australia and many other countries around the world have significantly altered the environment in which criminal activity can take place.

The broad view in the early days of the pandemic was some crimes would naturally decrease—those requiring access to public space, for instance, and human contact.

For example, under the routine activity theory in criminology, which focuses on the criteria that must be present for crimes to occur, the lockdown should have led to a significant decline in burglaries of homes. There were fewer suitable targets for burglaries (unoccupied houses) and an increase in capable guardians who could intervene (families staying at home).

The same theory can apply to violent crimes and sexual assaults—if you limit the ability of people to commit these crimes through lockdowns, it's reasonable to expect crime rates would decrease.

The statistics in Australia suggest these theories may be correct.

The NSW Bureau of Crime Statistics and Research found that in April, crime across many categories declined sharply compared to the same month for the past five years: robberies (down 42%), non-domestic assault (down 39%), sexual offenses (down 32%), break and enter of dwellings (down 29%), break and enter of non-dwellings (down 25%), stealing from motor vehicles (down 34%) and car theft (down 24%).

A similar pattern was noticeable in Queensland, comparing crime data for April to the same month in 2019—a 28% decline in unlawful entry of dwellings, 45% reduction in robberies and a 7% drop in sexual offenses.

Increases in crimes committed in private

Conversely, offenses that could be committed in private settings or remotely, such as cybercrimes, rose dramatically during the pandemic.

In Queensland, for instance, computer fraud was up 76% in April compared to the year before, while drug offenses increased by 13%.

There was also great concern that domestic violence would also increase during lockdown periods.

NSW police did not see an increase in domestic violence reports in April, compared to the previous year, and Queensland crime data shows breaches of domestic violence orders have remained stable since the start of the pandemic. The NSW Bureau of Crime Statistics and Research, however, said police could not rule out an increase in unreported domestic violence.

In contrast to this, police data for the Northern Territory showed a 25% spike in domestic violence-related assaults in parts of central Australia during the first months of the COVID-19 lockdown.
Routine activity theory (or the crime triangle). Credit: UN Office on Drugs and Crime

A study by the Australian Institute of Criminology (AIC) surveyed 15,000 Australian women to gage the prevalence of domestic violence during the lockdown period from February to May. It found 4.6% of women experienced physical or sexual violence from a partner and 11.6% reported experiencing emotionally abusive, harassing or controlling behavior.

The report noted more research was needed to understand the problem.

"Given the majority of women experiencing violence and abuse within their relationships do not engage with police or government or non-government agencies—particularly while they remain in a relationship with their abuser—this is a significant gap in knowledge."

Crime also down overseas, but homicides on the rise

Other countries reported similar decreases in crime. In England and Wales, crime dropped consistently by an average of 24% per month over a three-month period from April to June compared to the same period for 2019.

These figures, however, did not include fraud offenses, which increased during the pandemic. In March, reported frauds in the UK increased by 400%.

Scotland also saw an 18% decrease in overall crime in April compared to the same month in 2019. One of the few exceptions to this was a 38% rise in fraud.

In the US, however, the findings have been mixed. One study that looked at crime in 16 large cities from January to May (when lockdowns were coming into force) found reductions in residential burglaries and car thefts in some cities, but little to no change to non-residential burglaries and serious assaults (including homicides).

Another study looking at the effect of social distancing on crime in two cities, Los Angeles and Indianapolis, found it "had a statistically significant impact on a few specific crime types. However, the overall effect is notably less than might be expected given the scale of the disruption to social and economic life."

Finally, a major study by the University of Pennsylvania found overall crime across 25 cities in the US declined by 23% in the first month of the pandemic, compared to the average over five years of data for the same time period.

Notably, the study found crime declined even before stay-at-home orders were issued as people changed their normal routines and spent more time at home. Drug crimes saw the biggest decline of any crime category, while home burglaries, assaults and robberies were also down across the 25 cities.

However, the study found little change to homicide rates or shootings in the first month after stay-at-home orders. One possible reason for this, the authors note, is people committing these types of crime are unlikely to be concerned with stay-at-home orders.

In a separate analysis of crime data conducted by The New York Times, murders were up 21.8% in the 36 US cities it studied through at least May, compared to data for the same time period last year.

Other academics have said it is difficult to draw conclusions on homicide rates during the pandemic due to a lack of long-term data.

Further study of the impact of COVID-19 on crime will be required. In the UK, Leeds University has just been awarded funding to conduct such a study over the next 18 months.

Future challenges

Not only will law enforcement be required to adapt to the effect of COVID-19 responses on criminal behavior, the role of law enforcement is also being expanded to take on non-traditional roles in the pandemic.

And the full economic impact of the pandemic has yet to be seen. Many economies have been insulated to some degree by government assistance programs, but the extent to which a severe economic downturn could affect crime rates is still not known.


Explore furtherStudy shows domestic violence reports on the rise as COVID-19 keeps people at home
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