PRESS-NEWS.org - Press Release Distribution
FREE PRESS RELEASES DISTRIBUTION

Climate impacts drive east-west divide in forest seed production

Western forests may be less able to regenerate following large-scale diebacks

Climate impacts drive east-west divide in forest seed production
2021-02-23
(Press-News.org) DURHAM, N.C. -- Younger, smaller trees that comprise much of North America's eastern forests have increased their seed production under climate change, but older, larger trees that dominate forests in much of the West have been less responsive, a new Duke University-led study finds.

Declines in these trees' seed production, or fecundity, could limit western forests' ability to regenerate following the large-scale diebacks linked to rising temperatures and intensifying droughts that are now occurring in many states and provinces.

This continental divide, reported for the first time in the new study, "could dramatically alter the composition and structure of 21st century North American forests," said James S. Clark, Nicholas Distinguished Professor of Environmental Science at Duke, who led the research.

Knowing the contrasting responses occur -- and understanding why they happen -- will help scientists more accurately predict future changes to North American forests and develop conservation and management strategies to mitigate the changes, he said.

Researchers from 48 institutions collaborated with Clark on the peer-reviewed study, which appears Feb. 23 in Nature Communications.

Fecundity is a measure of trees' capacity to regenerate after diebacks and other large-scale disturbances by dispersing seeds to habitats where their odds of future survival are more favorable. It's an essential factor for determining future forest responses to climate change, but like many ecological processes it's noisy, highly variable and incredible hard to estimate.

Fecundity changes over time, based on changes in a tree's size, growth rate or access to light, water and other resources, and is driven by two indirect climate impacts -- the effects of growth that depend on climate, and the effects of climate that depend on tree size -- that currently aren't accounted for in the models used to predict future change.

"It was the only major demographic process driving forest response to climate change that we lacked field-based estimates on," Clark said.

To address this problem, he devised new statistical software that allowed him to synthesize decades of raw data on size, growth, canopy spread, and access to resources for nearly 100,000 individual trees at long-term research sites and experimental forests across North America. The unfiltered raw data revealed what previous meta-analyses based on averaged measurements had missed: At the continental scale, fecundity increases as a tree grows larger, up to a point. And then it begins to decline.

"This explains the East-West divide. Most trees in the East are young, growing fast and entering a size class where fecundity increases, so any indirect impact from climate that spurs their growth also increases their seed production," Clark said. "We see the opposite happening with the older, larger trees in the West. There are small and large trees in both regions, of course, but the regions differ enough in their size structure to respond in different ways.

"Now that we understand, in aggregate, how this all works, the next step is to apply it to individual species or stands and incorporate it into the models we use to predict future forest changes," he said.

The data used in the study came from trees in the Mast Inference and Prediction (MASTIF) monitoring network, which includes more than 500 long-term field research sites nationwide, including plots that are also part of the National Ecological Observation Network (NEON).

INFORMATION:

Other Duke authors on the study were Christopher L. Kilner, Jordan Luongo, Renata Poulton-Kamakura, Ethan Ready, Chantal D. Reid, C. Lane Scher, William H. Schlesinger, Shubhi Sharma, Samantha Sutton, Jennifer J. Swenson and Margaret Swift.

Funding came from the National Science Foundation, the Belmont Forum, NASA, and the Ministere de l'Enseignement Superieur de la Recherche et de l'Innovation "Make Our Planet Great Again" initiative.

In addition to Clark's primary faculty appointment at Duke's Nicholas School of the Environment, he holds a secondary appointment at the Université Grenoble Alpes' Institute National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement.

CITATION: "Continent-wide Tree Fecundity Driven by Indirect Climate Effects," J.S. Clark, R. Andrus, M. Aubry-Kientz, Y. Bergeron, M. Bogdziewicz, D.C. Bragg, D. Brockway, N.L. Cleavitt, S. Cohen, B. Courbaud, R. Daley, A.J. Das, M. Dietze, T.J. Fahey, I. Fer, J.F. Franklin, C.A. Gehring, G.S. Gilbert, C.H. Greenberg, Q. Guo, J. Hille Ris Lambers, I. Ibanez, J. Johnstone, C.L. Kilner, J. Knops, W.D. Koenig, G. Kunstler, J.M. LaMontagne, K.L. Legg, J. Luongo , J.A. Lutz, D. Macias, E.J.B. McIntire, Y. Messaoud, C.M. Moore, E. Moran, J.A. Myers, O.B. Myers, C. Nunez, R. Parmenter, S. Pearse, S. Pearson, R. Poulton-Kamakura, E. Ready, M.D. Redmond, C.D. Reid, K.C. Rodman, C.L. Scher, W.H. Schlesinger, A.M. Schwantes, E. Shanahan, S. Sharma, M. Steele, N.L. Stephenson, S. Sutton, J.J. Swenson, M. Swift, T.T. Veblen, A.V. Whipple, T.G. Whitham, A.P. Wion, K. Zhu, R. Zlotin; Feb. 23, 2021, Nature Communications. DOI: 10.1038/s41467-020-20836-3


[Attachments] See images for this press release:
Climate impacts drive east-west divide in forest seed production

ELSE PRESS RELEASES FROM THIS DATE:

Nonconscious brain modulation to remove fears, increase confidence

2021-02-23
In recent years, researchers have discovered ways to remove specific fears from the brain, increase one's own confidence, or even change people's preferences, by using a combination of artificial intelligence and brain scanning technology. Their technique could lead to new treatments for patients with conditions such as post-traumatic stress disorder (PTSD), phobias or anxiety disorders. But while this technique is extremely promising, in some individuals it remains unsuccessful. Why are there such differences in outcome? Better understanding how the brain can self-regulate its own activity patterns would go a long way toward establishing the technique for clinical use. The researchers who spearheaded this technique have thus released a unique dataset ...

Beta blockers can repair malformed blood vessels in the brain

Beta blockers can repair malformed blood vessels in the brain
2021-02-23
Peer review/Experimental study/Animals Propranolol, a drug that is efficacious against infantile haemangiomas ("strawberry naevi", resembling birthmarks), can also be used to treat cerebral cavernous malformations, a condition characterised by misshapen blood vessels in the brain and elsewhere. This has been shown by researchers at Uppsala University in a new study published in the scientific journal Stroke. "Up to now, there's been no drug treatment for these patients, so our results may become hugely important for them," says Peetra Magnusson of the University's Department of Immunology, Genetics and Pathology, who headed the study. Cerebral cavernous malformations (CCMs, also called cavernous angiomas or cavernomas) are vascular lesions ...

Pregnancy, stress, sleep issues, physiology among women's unique cardiovascular concerns

2021-02-23
DALLAS, Feb. 23, 2021 — Women face many female-specific risks for heart disease and stroke, including pregnancy, physical and emotional stress, sleep patterns and many physiological factors, according to multiple studies highlighted in this year’s Go Red for Women® special issue of the Journal of the American Heart Association, published online today. “Although cardiovascular disease is the leading cause of death in men and women, women are less likely to be diagnosed and receive preventive care and aggressive treatment compared to men,” said Journal of the American Heart Association Editor-in-Chief Barry London, M.D., Ph.D., Ph.D., the Potter Lambert Chair in Internal Medicine, director of the division ...

Basic cell health systems wear down in Huntington's disease, novel analysis shows

Basic cell health systems wear down in Huntingtons disease, novel analysis shows
2021-02-23
Using an innovative computational approach to analyze vast brain cell gene expression datasets, researchers at MIT and Sorbonne Université have found that Huntington's disease may progress to advanced stages more because of a degradation of the cells' health maintenance systems than because of increased damage from the disease pathology itself. The analysis yielded a trove of specific gene networks governing molecular pathways that disease researchers may now be able to target to better sustain brain cell health amid the devastating neurodegenerative ...

Climate-friendly foam building insulation may do more harm than good

2021-02-23
The use of the polymeric flame retardant PolyFR in "eco-friendly" foam plastic building insulation may be harmful to human health and the environment, according to a new commentary in Environmental Science & Technology. The authors' analysis identifies several points during the lifecycle of foam insulation that may expose workers, communities, and ecosystems to PolyFR and its potentially toxic breakdown products. With the climate crisis fueling demand for energy-efficient insulation, the production of PolyFR is increasing rapidly. That's because this flame retardant is added to all foam plastic building insulation in North America to comply with flammability codes, replacing the flame retardant ...

Researchers reveal genetic predisposition to severe COVID-19

Researchers reveal genetic predisposition to severe COVID-19
2021-02-23
HSE University researchers have become the first in the world to discover genetic predisposition to severe COVID-19. The results of the study were published in the journal Frontiers in Immunology. T-cell immunity is one of the key mechanisms used by the human body to fight virus infections. The staging ground for cell immunity development is the presentation of virus peptides on the surface of infected cells. This is followed by activation of T lymphocytes, which start to kill the infected cells. The ability to successfully present virus peptides is largely determined by genetics. In human cells, human leukocyte antigen class I (HLA-I) molecules are responsible for this presentation. The set of six such molecules is unique in every ...

Novice drivers talking on hand-held smartphones are more likely to run red-lights

2021-02-23
Young novice drivers who speak into hand-held smartphones while driving are also likely to drive while under the influence of drink or drugs, according to researchers at Lero, the Science Foundation Ireland Research Centre for Software. The study "Smartphone Use While Driving: An Investigation of Young Novice Driver (YND) Behaviour," also found that speaking on a hand-held phone is strongly correlated with high-risk driving behaviours such as overtaking on the inside of the car ahead, speeding, driving without a valid licence and driving while intoxicated. Lero researchers, surveyed 700 German Young Novice Drivers ...

COVID-19 infection in pregnancy not linked with still birth or baby death

2021-02-23
COVID-19 infection in pregnancy is not associated with stillbirth or early neonatal death, according to a new study. However the research, from over 4000 pregnant women with suspected or confirmed COVID-19, also found women who had a positive test were more likely to have a premature birth. The research, led by scientists from Imperial College London and published in the journal Ultrasound in Obstetrics and Gynecology, used data from the UK and the USA. The study team looked at data from 4004 pregnant women who had suspected or confirmed COVID-19. Of these women, ...

Environmental policies not always bad for business, study finds

2021-02-23
ITHACA, N.Y. - Critics claim environmental regulations hurt productivity and profits, but the reality is more nuanced, according to an analysis of environmental policies in China by a pair of Cornell economists. The analysis found that, contrary to conventional wisdom, market-based or incentive-based policies may actually benefit regulated firms in the traditional and "green" energy sectors, by spurring innovation and improvements in production processes. Policies that mandate environmental standards and technologies, on the other hand, may broadly harm output and profits. "The conventional wisdom is not entirely ...

Polymer film protects from electromagnetic radiation, signal interference

Polymer film protects from electromagnetic radiation, signal interference
2021-02-22
As electronic devices saturate all corners of public and personal life, engineers are scrambling to find lightweight, mechanically stable, flexible, and easily manufactured materials that can shield humans from excessive electromagnetic radiation as well as prevent electronic devices from interfering with each other. In a breakthrough report published in Advanced Materials--the top journal in the field-- engineers at the University of California, Riverside describe a flexible film using a quasi-one-dimensional nanomaterial filler that combines excellent electromagnetic shielding with ease of manufacture. "These novel films are promising for high-frequency communication technologies, which require electromagnetic ...

LAST 30 PRESS RELEASES:

Why some coronavirus strains are more infectious than others

Scientists reveal details of antibodies that work against Zika virus

Scientists uncover new details of SARS-CoV-2 interactions with human cells

Antibodies recognize and attack different SARS-CoV-2 spike shapes

How SARS-CoV-2's sugar-coated shield helps activate the virus

A Canadian success story: world-first to treat Fabry disease with gene therapy

Chimpanzees and humans share overlapping territories

Allergy season starts earlier each year due to climate change and pollen transport

Study shows opioid use among US patients with knee osteoarthritis costs 14 billion dollars in societal costs

On the line: Watching nanoparticles get in shape

A-maze-ing pheasants have two ways of navigating

CAR T-cell therapy generates lasting remissions in patients with multiple myeloma

Fantastic voyage: Nanobodies could help CRISPR turn genes on and off

Baby mice have a skill that humans want - and this microchip might help us learn it

New discoveries on the containment of COVID-19 finds travel bans are of limited value

UM scientists achieve breakthrough in culturing corals and sea anemones cells

New shape-changing 4D materials hold promise for morphodynamic tissue engineering

Apollo rock samples capture key moments in the Moon's early history, study find

COVID-19 isolation linked to increased domestic violence, researchers suggest

What to do when a mammogram shows swollen lymph nodes in women just vaccinated for COVID

After Hurricane Irma, soundscape reveals resilient reef ecosystem

Parker Solar Probe offers stunning view of Venus

Ancient skeletal hand could reveal evolutionary secrets

Study finds human-caused North Atlantic right whale deaths are being undercounted

Bearded seals are loud -- but not loud enough

Tool that more efficiently analyzes ocean color data will become part of NASA program

Paleontologists discover new insect group after solving 150-year-old mystery

'Miracle poison' for novel therapeutics

Over 80% of Atlantic Rainforest remnants have been impacted by human activity

Researchers use machine learning to identify autism blood biomarkers

[Press-News.org] Climate impacts drive east-west divide in forest seed production
Western forests may be less able to regenerate following large-scale diebacks