(Press-News.org) LOWELL, Mass. - Researchers led by a UMass Lowell environmental science professor say mercury measurements in a Massachusetts forest indicate the toxic element is deposited in forests across the globe in much greater quantities than previously understood.
The team's results underscore concern for the health and well-being of people, wildlife and waterways, according to Prof. Daniel Obrist, as mercury accumulating in forests ultimately runs off into streams and rivers, ending up in lakes and oceans.
Mercury is a highly toxic pollutant that threatens fish, birds, mammals and humans. Hundreds of tons of it are released into the atmosphere each year by coal-burning power plants, as well as through gold mining and other industrial processes, and the pollutant is distributed by winds and currents across the globe. Long-term exposure to mercury, or consuming food containing high levels of the pollutant, can lead to reproductive, immune, neurological and cardiovascular problems, according to Obrist, chair of UMass Lowell's Department of Environmental, Earth and Atmospheric Sciences.
Forests constitute the world's most abundant, productive and widespread ecosystems on land, according to Obrist, who said the study is the first that examines a full picture of how mercury in the atmosphere is deposited at any rural forest in the world, including the deposition of mercury in its gaseous form, which most previous studies do not address.
"Trees take up gaseous mercury from the atmosphere through their leaves and as plants shed their leaves or die off, they basically transfer that atmospheric mercury to the ecosystems," he said.
The results of the project, which is supported by a three-year, $873,000 grant from the National Science Foundation (NSF), were published today in an issue of the Proceedings of the National Academy of Sciences. UMass Lowell student Eric Roy, a double-major in meteorology and mathematics from Lowell, is among the study's co-authors.
For the past 16 months, the team has measured how mercury in the atmosphere gets deposited at Harvard Forest in Petersham, a nearly 4,000-acre site that includes hardwood deciduous broadleaf trees such as red oak and red maple that shed their leaves every year. A set of measurement systems placed at various heights on the forest's 100-foot-tall research tower assessed the site's gaseous mercury deposition from the tree canopy to the forest floor.
"Seventy-six percent of the mercury deposition at this forest comes from gaseous atmospheric mercury. It's five times greater than mercury deposited by rain and snow and three times greater than mercury that gets deposited through litterfall, which is mercury transferred by leaves falling to the ground and which has previously been used by other researchers as a proxy for estimating gaseous mercury deposition in forests," Obrist said.
"Our study suggests that mercury loading in forests has been underestimated by a factor of about two and that forests worldwide may be a much larger global absorber and collector of gaseous mercury than currently assumed. This larger-than-anticipated accumulation may explain surprisingly high mercury levels observed in soils across rural forests," he said.
Plants seem to dominate as a source of mercury on land, accounting for 54 to 94 percent of the deposits in soils across North America. The total global amount of mercury deposited to land currently is estimated at about 1,500 to 1,800 metric tons per year, but it may be more than double if other forests show similar levels of deposition, according to Obrist.
The researchers are continuing their work at a second forest in Howland in northern Maine. Howland Forest, a nearly 600-acre research site full of evergreens that retain their leaves year-round, offers a distinctly different habitat than the deciduous forest in Petersham. Assessing both forests will allow researchers to examine differences in mercury accumulation between different forest types, Obrist said.
The work is providing a hands-on research experience for Roy, a UMass Lowell Honors College student who was invited to become a member of the university's Immersive Scholar program in 2019. The initiative enables first-year students with outstanding academic credentials to participate in lab work and research right from the start of their academic studies.
"It's really exciting to be a co-author," Roy said. "This study allowed us to quantify how much mercury is being accumulated in this type of forest. Modelers can use these results to improve their understanding of how mercury cycles through the environment on a global scale and how that might change in the future."
Roy helped analyze the data collected in the field.
"Eric's contributions to the study are tremendous. It's not very common for an undergrad to play such an important role in a major, federally funded research project," Obrist said. "His work is really impressive and he has become more and more active in data analysis and doing complex flux calculations and data processing. He really earned himself second author position in the paper in the Proceedings of the National Academy of Sciences."
INFORMATION:
Other contributors to the study include Asst. Prof. Róisín Commane of Columbia University; students and postdoctoral researchers from UMass Lowell and Columbia University; and collaborators from Harvard University; the Desert Research Institute in Reno, Nevada; and the Northwest Institute of Eco-Environment and Resources and the University of the Chinese Academy of Sciences in Lanzhou. Additional research support was provided by the U.S. Department of Energy.
UMass Lowell is a national research university offering its more than 18,000 students bachelor's, master's and doctoral degrees in business, education, engineering, fine arts, health, humanities, sciences and social sciences. UMass Lowell delivers high-quality educational programs and personal attention from leading faculty and staff, all of which prepare graduates to be leaders in their communities and around the globe. http://www.uml.edu
PITTSBURGH, July 12, 2021 - States that legalize recreational marijuana experience a short-term decline in opioid-related emergency department visits, particularly among 25- to 44-year-olds and men, according to an analysis led by the University of Pittsburgh Graduate School of Public Health.
Published today in the journal Health Economics, the study shows that even after the temporary decline wears off, recreational cannabis laws are not associated with increases in opioid-related emergency department visits.
"This isn't trivial--a decline in opioid-related emergency department visits, even if only for six months, is a welcome public health development," said lead author Coleman Drake, Ph.D., assistant professor ...
MINNEAPOLIS - The American Academy of Neurology (AAN), the world's largest association of neurologists with more than 36,000 members, is issuing ethical guidance for neurologists and neuroscience professionals who care for people with Alzheimer's disease and other dementias. The new position statement is published in the July 12, 2021 online issue of Neurology®, the medical journal of the American Academy of Neurology. This update to the 1996 AAN position statement was developed by the Ethics, Law, and Humanities Committee, a joint committee of the American Academy of Neurology, American Neurological Association and Child Neurology Society.
"Dementia care and scientific understanding have advanced considerably, including greater recognition of non-Alzheimer's dementias and advances ...
The Black Lives Matter movement has brought increasing attention to disparities in how police officers treat Black and white Americans. Now, research published by the American Psychological Association finds that disparity may exist even in subtle differences in officers' tone of voice when they address Black and white drivers during routine traffic stops.
In the study, published in the Journal of Personality and Social Psychology, researchers gathered short audio excerpts from police body camera footage and found that when officers spoke to Black men at traffic stops, their tone of voice conveyed less warmth, respect and ease than when they spoke to white men. The researchers also found that these subtle negative interactions ...
INFORMS Journal Management Science Study Key Takeaways:
Lack of direct airline routes limit the flexibility of organ transplantation policies.
A new airline route can increase the number of kidneys shared between different regions by more than 7% while also decreasing the organ discard rate.
An increase in the quantity of kidneys does not come with a decrease in kidney quality.
CATONSVILLE, MD, July 12, 2021 - It's a supply and demand problem, it's a transportation problem, it's a donor problem - and that just scratches the surface. According ...
[Points]
319 Tb/s long-haul transmission of wideband (>120 nm) S, C and L-bands signal using 552 PDM-16QAM, wavelength-division multiplexed channels in a 4-core optical fiber
Long-distance transmission over 3,001 km enabled by adoption of both erbium and thulium doped-fiber amplifiers and distributed Raman amplification
Demonstration shows potential of SDM fibers with standard-cladding diameter and compatibility with existing cabling technologies for near-term adoption of high-throughput SDM fiber systems
[Abstract]
Researchers from the National Institute of Information and Communications Technology (NICT, President: TOKUDA ...
When we think about singularities, we tend to think of massive black holes in faraway galaxies or a distant future with runaway AI, but singularities are all around us. Singularities are simply a place where certain parameters are undefined. The North and South Pole, for example, are what's known as coordinate singularities because they don't have a defined longitude.
Optical singularities typically occur when the phase of light with a specific wavelength, or color, is undefined. These regions appear completely dark. Today, some optical singularities, including ...
Los Alamos, N.M., July 12, 2021--For the first time, the long-theorized neutron-clustering effect in nuclear reactors has been demonstrated, which could improve reactor safety and create more accurate simulations, according to a new study recently published in the journal Nature Communications Physics.
"The neutron-clustering phenomenon had been theorized for years, but it had never been analyzed in a working reactor," said Nicholas Thompson, an engineer with the Los Alamos Advanced Nuclear Technology Group. "The findings indicate that, as neutrons fission and create more neutrons, some go on to form large lineages of clusters while others quickly die off, resulting in so-called 'power tilts,' ...
(Boston)--Despite the availability of numerous effective birth control methods, more than 40 percent of pregnancies worldwide are unintended. In addition to contributing significantly to population growth, unintended pregnancies can have pronounced adverse effects on maternal physical, mental and economic wellbeing.
Researchers from Boston University School of Medicine (BUSM) and ZabBio (San Diego, CA) have developed an anti-sperm monoclonal antibody, the Human Contraception Antibody (HCA), which they found to be safe and possess potent sperm agglutination (clumping) and immobilization activity in laboratory tests.
"HCA appears to be suitable for contraceptive use and could be administered vaginally in a dissolvable film for a ...
A research team from the University of Göttingen and the University of British Columbia (Canada) has investigated how people in five different countries react to various usages of genome editing in agriculture. The researchers looked at which uses are accepted and how the risks and benefits of the new breeding technologies are rated by people. The results show only minor differences between the countries studied - Germany, Italy, Canada, Austria and the USA. In all countries, making changes to the genome is more likely to be deemed acceptable when used in crops rather than in livestock. The study was published in Agriculture and Human Values.
Relatively new breeding technologies, such as CRISPR gene editing, have enabled a range of new opportunities for plant and animal breeding. ...
The sensory cells in the inner ear and the touch receptors in the skin actually have a lot in common, according to a new study from the USC Stem Cell laboratory of Neil Segil published in the Proceedings of the National Academy of the Sciences (PNAS).
"There are striking similarities in the development of two types of specialized sensory cells: the so-called 'hair cells' that receive sound vibrations in the inner ear, and the Merkel cells that sense light touch at the surface of the skin," said Segil, who is a Professor in the Department of Stem Cell Biology and Regenerative Medicine, and the USC Tina and Rick Caruso Department of Otolaryngology ...
