Tuesday, December 17, 2024

New research about drought impacts on wildlife can inform conservation strategies

Animals may endure three-year droughts nearly seven times more often.

USDA Forest Service - Rocky Mountain Research Station

Giant Kangaroo Rat — image:
A giant kangaroo rat, rescued and safely released by a permit-holder during a PG&E pipeline excavation project. Giant kangaroo rats are native to dry habitats in CA and adapted to short droughts, though multi-year droughts can cause populuations to plummet. Increased drought adds to conservation concerns for this endangered species.
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Credit: Ryan Donnelly

FORT COLLINS, Colo., December 11, 2024 — People around the world are dealing with drought, so it’s not shocking that it affects wildlife, too: lack of moisture contributes to habitat loss, affects how animals compete for resources, and leads to dehydration and heat stress. The surprising part? The extreme degree to which many animals may need to adapt.

New research predicts that many wildlife species in the continental United States will experience year-long droughts nearly five times as often in the coming decades (2050-2080) than they did historically (1950-2005). In an even more dramatic turn of events, three-year droughts may become nearly seven times more frequent.

“The degree of increased drought exposure for each species in our analysis strongly depends on future greenhouse gas concentrations,” said Dr. Merijn van den Bosch, the lead author of the study. “But even under a lower-concentration scenario, virtually all vertebrates face increased year-long and multi-year droughts in the second half of this century. The implications will depend on the species and the length of the drought.”

For example, the endangered giant kangaroo rat, which is native to dry habitats in California, has adapted to occasional short droughts. However, populations can plummet after multi-year droughts, compounding existing threats, including a loss of nearly all their historic habitat. This study shows that much of the remaining giant kangaroo rat range soon could face these longer droughts much more often. “That does not bode well for this already-endangered species,” said van den Bosch.

Likewise, the ranges of many game species whose populations are not currently at risk—including certain ducks and other waterfowl and ungulates like elks—also will face more frequent year-long and three-year droughts in the future. This trend could have implications for wildlife and game management.

Scientists aimed to identify areas with both high biodiversity and large predicted increases in drought to provide information about places where adaptive water management or habitat restoration could benefit the most wildlife species. They used state-of-the-art modeling techniques to predict future scenarios based on six different projections of temperature and moisture conditions. Then, they compared the frequency of observed and projected drought exposure to the range maps of 349 birds, 339 mammals, 280 amphibians, and 253 reptile species and created regional summaries.

It turned out, after they adjusted for land area, that the southwestern United States had the highest number of different species, the highest number of drought-threatened species, and the highest predicted change in drought exposure. “Some of the areas expected to see the greatest increase in drought, such as the southwestern U.S., are already quite dry,” said Dr. Zack Steel. “Many species living in these regions are adapted to periodic droughts, but the concern is that if they are already near the limit of what they can tolerate, the large increase in drought we’re expecting can have grave consequences for these ecosystems and the wildlife that depend on them.”

This research was led by Dr. Merijn van den Bosch, post-doctoral scientist at Colorado State University and the Rocky Mountain Research Station, along with senior author, Dr. Zack Steel, a research ecologist with the Rocky Mountain Research Station. Additional coauthors of this research include Dr. Jennifer Costanza from the USDA Forest Service’s Southern Research Station, Dr. Ryan Peek from California Department of Fish and Wildlife, and Dr. John Mola from Colorado State University. For more information, please visit the scientific publication in Communications Earth & Environment.

Journal

Communications Earth & Environment

DOI

10.1038/s43247-024-01880-z

Method of Research

Computational simulation/modeling

Subject of Research

Animals

Article Title

Climate change scenarios forecast increased drought exposure for terrestrial vertebrates in the contiguous United States

Study finds parents more open to racially diverse media for children than previously thought

Majority of parents recalled watching diverse programming with kids; while racial-ethnic identity predicted attitudes but not beliefs about such content

University of Kansas

LAWRENCE — New research from the University of Kansas has found that most parents recall watching media with diverse racial and ethnic portrayals of characters with their children and that their own racial-ethnic identity predicted their attitudes toward such content, but not necessarily their beliefs.

Judy Watts, assistant professor of journalism & mass communications at KU, led a study in which 367 Black, Latinx and white parents of children ages 4-7 were surveyed about media they’ve consumed with their kids. Two-thirds of respondents recalled consuming media such as television, movies, video games or books with portrayals of diverse characters and those of races different than their own.

“I was interested in seeing what led some parents in selecting what racially and ethnically diverse media to watch with their children,” Watts said. “My previous research was more conceptually focused on things kids learn in school or media effects over the lifespan. Childhood is an important time to learn about ourselves and others who may be different from ourselves.”

For the study, parents were asked to identify their race, ethnicity and that of their children. The Black, white and Latinx parents were also asked about their attitudes about media representations of race, such as if portrayals they recalled were helpful or not to determine attitudes about such media. They were also asked about ethnic/racial identity with questions such about how strongly they feel they belong with people who share their race and/or ethnicity.

Findings showed that Black and Latinx parents differed significantly on racial/ethnic identity than white parents, but not from each other, with both reporting higher levels of racial identity. That held consistent with previous research on ethnic/racial identity. The parents were also asked about the type of content featuring racial/ethnic depictions they recalled consuming with their children, how diverse the characters were and what sort of situations they were depicted in.

“Seeing what types of content families watched was very intriguing. Black families tended to watch content featuring members of their race. That is possibly because that type of diverse content wasn’t always as readily available as it is now,” Watts said. “Latinx families watched a lot of content featuring characters of their own race/ethnicity, but also with mixed characters. That could speak to things like assimilation into culture.”

The research was tested on themes of social identity gratification and multicultural theories. The former holds that people prefer to consume depictions of people similar to themselves, while the latter holds that people who have a strong racial/ethnic identity are favorable to depictions of other races and ethnicities as well. Each theory was partially supported by findings that ultimately, parents are open to diverse content for their children and their attitudes toward racially and ethnically diverse media portrayals are more open than previous research has indicated.

“This research shows that parents want to show their children diverse content that reflects their own racial/ethnic identities and that they’re open to diverse content as well,” Watts said. “It shows parents are supportive of diversity in content of media their children consume. Parents have various socialization goals for their children. They want to help them learn about their own identities and expose them to others. I think it shows it’s not a dichotomous decision or that it has to be one or the other.”

The study was supported by a research cultivation grant from the National Research Communication Association and was published in the journal Communication Research Reports.

Watts, who conducts research into media effects and influences, said the study’s results show parents have varying goals for using media to help their children learn about themselves as well as their identities. She is conducting follow-up research examining explicit and implicit portrayals of racial interactions in children’s media. Specifically, she is comparing portrayals including anthropomorphized animals and human characters and their use of racial characteristics to analyze if children understand such racial cues, which characters they liked and to which they assign morality.

The current study showed that nearly two-thirds of parents recalled seeing racially and ethnically diverse portrayals of characters with their children, often in positive contexts, such as characters with differing backgrounds being friends.

“I think this suggests that parents are open to and seeking racially and ethnically diverse content and having more diverse content available in children’s media in recent decades has been helpful,” Watts said. “It also helps us understand parents’ motivations in media they choose for their kids.”

Journal

Communication Research Reports

DOI

10.1080/08824096.2024.2420056

Method of Research

Survey

Subject of Research

People

Article Title

Exposure to diverse ethnic-racial media: Black, Latinx, and White Parents’ attitudes toward media-based ethnic-racial socialization

CRIMINAL CAPITALI$M

Wedel studying how transnational networks shape non-Western offshore spaces

George Mason University

Janine Wedel, Distinguished University Professor, Schar School of Policy and Government, received money for a project on the growing non-Western offshore system used by transnational networks emanating from autocratic regimes such as Russia to skirt international checks and balances. Wedel and her colleagues are investigating these informal networks and how they enable “weaponized corruption” — the use of corruption for geopolitical ends — and the evasion of Western sanctions. They are also identifying emerging threats to global security and democratic integrity they present.

Wedel received $445,000 from Carnegie Corporation of New York, Inc., for this research. Funding began in Oct. 2024 and will end in late Sept. 2026.

###

ABOUT GEORGE MASON UNIVERSITY

George Mason University is Virginia’s largest public research university. Located near Washington, D.C., Mason enrolls more than 40,000 students from 130 countries and all 50 states. Mason has grown rapidly over the past half-century and is recognized for its innovation and entrepreneurship, remarkable diversity, and commitment to accessibility. In 2023, the university launched Mason Now: Power the Possible, a one-billion-dollar comprehensive campaign to support student success, research, innovation, community, and stewardship. Learn more at gmu.edu.

Long COVID’s effects on employment: financial distress, fear of judgment

In study, patient perspectives highlight how providers can help

Ohio State University

COLUMBUS, Ohio – Though research has shown that people with long COVID are more likely to be unemployed, the statistics don’t reveal what patients go through before they cut their hours, stop working or lose their jobs.

In a new study involving interviews of people with long COVID, researchers from The Ohio State University describe how the prolonged illness has affected not only patients’ job status, but also their overall well-being.

On top of symptoms including brain fog, fatigue, weakness and headaches, study participants reported lacking enough energy to do anything after work, loss of income and added insurance expenses when employment ended or changed, and emotional distress that comes with managing a misunderstood illness.

“For many individuals we talked to, their lives have been completely changed because of this chronic condition. And that’s really changed how they see themselves, how they experience life, how they interact with their families, how they provide for their families,” said lead author Sarah MacEwan, assistant professor of general internal medicine in Ohio State’s College of Medicine.

“In some cases, incredible financial instability has upended their lives. They’re facing extremely difficult choices and also trying to take care of themselves. It’s so important that we hear from them so we can improve the ways we can support them.”

Awareness of these employment-related challenges may help clinicians provide more holistic care to people with long COVID, researchers say. Examples include connecting patients to financial assistance, referring them to mental health practitioners or expediting requests for workplace accommodations.

The research was published recently in the Journal of General Internal Medicine.

MacEwan and colleagues conducted one-on-one interviews in late summer 2022 with 21 adult patients receiving treatment in the post-COVID recovery clinic at Ohio State Wexner Medical Center. Participants reported they had been doing well in daily life before having COVID-19 and were struggling with the effects of lingering symptoms for three or more months after an acute infection. They ranged in age from 19 to 68, three-fourths were women, and most were first infected with the SARS-CoV-2 virus in 2020.

Participants reported the illness interfered with both their work responsibilities and efforts to maintain work-life balance.

“Some quit their jobs because they just couldn’t handle working anymore. Some reduced their hours. And then some were involuntarily terminated from their jobs because of their symptoms,” said MacEwan, an investigator in Ohio State’s Center for the Advancement of Team Science, Analytics and Systems Thinking in Health Services and Implementation Science Research.

There were both financial and emotional repercussions. Loss of income followed either being unable to work, changing to a job with lower pay or having to reduce work hours. Those whose insurance status changed often had to spend more on policies that provided less coverage – all in the context of needing more care because they were chronically ill.

Participants also described feelings of loss of identity related to their professional and home lives and fear of judgment and stigma at work and among friends and family. In an earlier paper, the research team noted some patients faced skepticism in health care settings.

“One thing we’ve uncovered through this work is people not being believed by their providers about their symptoms or being brushed off or pushed into other diagnoses that they feel don’t reflect their experience,” MacEwan said. “It’s a real question of whether they are getting what they need from the providers they’re able to reach where they are.”

The current article focused in part on how patients made adjustments to get through the day – developing coping strategies they created or that were recommended by their care team, and accessing employer disability benefits and workplace accommodations.

“Some came up with solutions on their own, but it was wonderful to hear that great suggestions also came from additional specialists or therapists that these individuals were seeing,” MacEwan said.

Respondents reported taking frequent rest breaks, eliminating distractions, making lists, emailing themselves a daily report of completed projects, using visual prompts on whiteboards or talking themselves through tasks. Some patients were encouraged by health care providers to seek short- or long-term disability benefits or workplace accommodations such as remote work and flex time. Many participants said initial support from employers eventually waned.

Long COVID is federally recognized as a potential disability, which provides some employment protection to patients. The study authors noted that clinicians recommending established interventions such as rest and pacing may need to anticipate how such treatment strategies affect employment, financial status and mental health – and be ready to connect patients with resources to address the strains linked to making complex life choices.

“It’s important that we use lived experience to understand the needs of the population and not make assumptions. There are a lot of good ideas already out there, and people with other chronic conditions have solutions for some of these problems,” MacEwan said. “So maybe we don’t need to reinvent the wheel, but we certainly need to identify the needs and take steps to fill those gaps.”

This work was supported by a grant from the National Cancer Institute.

Co-authors, all from Ohio State, were Saurabh Rahurkar, Willi Tarver, Leanna Perez Eiterman, Halia Melnyk, Ramona Olvera, Jennifer Eramo, Lauren Teuschler, Alice Gaughan, Laura Rush, Stacy Stanwick, Susan Bowman Burpee, Erin McConnell, Andrew Schamess and Ann Scheck McAlearney.

Contact: Sarah MacEwan, sarah.macewan@osumc.edu

Written by Emily Caldwell, Caldwell.151@osu.edu; 614-292-8152

Journal

Journal of General Internal Medicine

DOI

10.1007/s11606-024-09062-5

Subject of Research

People

Article Title

The Impact of Long COVID on Employment and Well-Being: A Qualitative Study of Patient Perspectives

In Atlantic City, NJ, pandemic changed police response to mental health needs

Greatest impact related to dispatched calls soon after start of COVID-19

Crime and Justice Research Alliance

The onset of the COVID-19 pandemic not only threatened individuals’ physical health but also seriously strained mental health and access to care. A new study analyzed police data from one U.S. city before and after the start of the pandemic to examine whether the frequency of mental health calls for service and police-initiated stops for mental health reasons changed. Police involvement in responding to mental health situations changed slightly after COVID-19 began, with the greatest impact related to dispatched calls in early 2020.

The study, by researchers at Stockton University, is published in Criminal Justice Policy Review.

“Researchers have amassed evidence of the negative impact of COVID-19 on mental health, with anxiety and depression the most common disorders, and increases in alcohol and recreational drug use,” according to Christine Tartaro, distinguished professor of criminal justice at Stockton University, who led the study. “But while we know that the pandemic changed daily social, work, and leisure routines for many, researchers are still seeking to understand how these adjustments affected components of the criminal justice system.”

Tartaro is an expert whose work is promoted by the NCJA Crime and Justice Research Alliance, which is funded by the National Criminal Justice Association.

In the early years of COVID-19, the negative effects of the pandemic on mental health were not distributed equally across the population. People from socially disadvantaged backgrounds and with pre-existing mental health challenges and those who lacked access to services reported the most severe problems. In addition, individuals changed how they sought help and organizations limited their face-to-face contact with consumers.

In this study, researchers sought to determine whether the frequency of police involvement in mental health care changed over the first years of the pandemic. They analyzed more than 2,400 police calls—calls for service and officer-initiated stops that involved mental health—in Atlantic City, NJ, from January 2019 to December 2022. This span represents the period before and after New Jersey’s governor announced stay-at-home orders in mid-March 2020. The study estimated the effect of the pandemic on police involvement in mental health calls using interrupted time-series analysis.

The study found a temporary reduction in dispatched police officers during the first few months of the pandemic, but no long-term trend through 2022. In addition, there was a slight decrease in police-initiated contact for mental health calls after the initiation of COVID-19 restrictions. The study suggests that the pandemic affected how police were involved in providing mental health care, with the greatest impact related to dispatched calls for mental health services in the initial weeks after the COVID-19 outbreak.

The authors suggest that it is unlikely the reduction in dispatched calls early in the pandemic reflected a decline in the need for mental health services. Instead, it was probably the result of a combination of stay-at-home orders that reduced interpersonal contact and a reluctance to call for help during the early days of COVID-19 to avoid hospitals. Reductions in tourism (i.e., fewer people in the city) also likely had an effect.

Among the study’s limitations, the authors note that because their analysis included only calls labeled exclusively as mental health calls, it likely included just a fraction of total calls the police department received for mental health concerns. In addition, because Atlantic City is a unique location, with a heavy reliance on tourism and a disproportionate amount of homelessness, the findings from this study may not generalize to other jurisdictions.

“Although research suggests that police limited their proactive enforcement in the early days of the pandemic, our study found that police-initiated contact with people with mental illness in Atlantic City did not change substantially from January 2019 through 2022,” notes Ruibin Lu, associate professor of criminal justice at Stockton University, who coauthored the study. “Future studies might assess why this occurred.”

The research was supported by the Bureau of Justice Assistance and the Justice and Mental Health Collaboration Program: Embedding Clinicians in Law Enforcement Agencies.

Journal

Criminal Justice Policy Review

DOI

10.1177/08874034241303024

Article Title

The Impact of the COVID-19 Pandemic on Police Involvement in Mental Health Calls for Service

Mcity unveils digital twin, making its physical AV testing facility available for free in the virtual world

First open-source 3D digital twin for mobility systems testing could help speed autonomous and connected vehicle research

University of Michigan

Images of Mcity test track and digital twin

The first open-source digital twin of the Mcity Test Facility—the University of Michigan's test center for connected and autonomous vehicles and technologies—is now available to the public, giving researchers around the world a new free tool.

A digital twin is a virtual representation of a physical environment that also exchanges data with that environment, enabling simulation and testing. The new Mcity digital twin, developed with support from the National Science Foundation, is the first open-source digital twin for mobility systems testing, including autonomous driving. It provides a faster, safer, less expensive way to test autonomous and connected vehicle software.

Researchers anywhere can use the facility's features—with a variety of road materials, markings, signals and intersections—to test their autonomous algorithms without having to make the trip to Ann Arbor.

"This takes our almost 10-year-old track and puts the digital replica directly over it," said Greg Stevens, Mcity's director of research. "That's a living, breathing manifestation of that physical track where people can do mixed reality testing and development."

The digital twin works with TeraSim, an open-source traffic simulator developed by Mcity researchers. It introduces other road users, such as pedestrians, cyclists and other drivers, and generates safety-critical events like potential collisions. Using traffic behavioral models calibrated with real-world data, it simulates both normal and high-risk driving scenarios.

Mobility officials have touted AVs, along with connected vehicles and infrastructure, as a path to safer, more efficient and equitable transportation. Still, a great deal of research remains ahead before the technologies will produce everyday benefits for a large portion of the population. Testing in the real world takes time and money and creates a host of safety issues, but virtual testing can enable control software to demonstrate a high level of safety ahead of that stage.

"You can drive millions of miles in your AV in a digital twin built off of a real-world environment before your AV actually touches the real world," said Darian Hogue, an Mcity software engineer who helped develop the digital twin. "With this, we can control all kinds of factors. That includes controlling and manipulating simulated pedestrian traffic—a factor that is random in the real world. This focuses and accelerates simulated testing."

Opened in 2015, the Mcity Test Facility is the world's first purpose-built proving ground for connected and automated vehicles. Its physical features include:

A simulated downtown area with urban streets.
A 1,000-foot straightaway, plus access ramps, a curve and a traffic circle.
Multiple road surfaces with a variety of road markings and crossing types.
Traffic signals and traffic signs.
Bridge deck, underpass, guardrails, barriers and crash attenuators.
House and garage exterior with accessibility ramp for first-mile/last-mile testing, deliveries and ride hailing.

Mcity is continuously adding new features, and officials have worked to make the facility and its technologies available to a larger group of researchers. In 2022, a $5.1 million grant from the National Science Foundation funded development of Mcity's digital infrastructure, enabling remote use of the Mcity Test Facility—dubbed Mcity 2.0. The 2022 grant also funded creation of the Mcity digital twin.

Mcity officially launched its remote use capabilities in October. Researchers operating from their home bases can test their autonomous algorithms in virtual and mixed reality environments by connecting to Mcity's cloud-based digital infrastructure. Using 5G wireless communications, they can control physical vehicles and traffic signals on Mcity's test streets and receive real-time data in return—all while protecting proprietary information.

"What differentiates the Mcity digital twin is that it supports virtual testing, while remote use involves testing a physical vehicle at our physical test track from a remote location," said Mcity Director Henry Liu, professor of civil and environmental engineering and the Bruce D. Greenshields Collegiate Professor.

"As an open-source tool, the Mcity digital twin lowers barriers to use of the test facility by technology developers and researchers. The digital twin could also help developers better prepare for on-site testing at Mcity."

Written by Jim Lynch, U-M College of Engineering

Detailed bedbug genome analysis may improve pesticides

UT Arlington study sequencing the pest’s genome may help prevent outbreaks

University of Texas at Arlington

Updated bedbug genome — image:
“This new high-quality reference genome provides a valuable resource for enhancing scientific investigations into this medically and economically resurging pest,” said author Todd Castoe, professor of biology at UTA.
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Credit: Courtesy UT Arlington

Bedbugs. Just mentioning the tiny, biting insects that live on human blood and infest mattresses, couches, and bedding strikes fear into most people. In addition to the anxiety, itching, and rashes an outbreak can cause, bedbugs can be difficult to identify and expensive to treat.

Thanks to a new University of Texas at Arlington study published in the Journal of Heredity, scientists now have a better genetic understanding of the insect. The research offers an updated genome analysis of the common bedbug Cimex lectularius, providing new insight for those working to prevent bedbug infestation, develop remediation strategies and track pesticide resistance.

“This new high-quality reference genome provides a valuable resource for enhancing scientific investigations into this medically and economically resurging pest,” said author Todd Castoe, professor of biology at UTA.

“We now have an important additional tool for studying patterns of human-associated evolution and adaption for this insect that has wreaked havoc on human populations since the beginning of civilization,” added co-author Yannick Francioli, a Ph.D. student in Dr. Castoe’s lab.

Although bedbugs have been mentioned in the written record for more than 3,000 years, the pest rose to prominence 1940s, when infestations plagued military bases during World War II. With the introduction of the powerful pesticide DDT (dichlorodiphenyltrichloroethane), the insect was thought to be eradicated in many industrialized nations.

In the 1990s, a combination of the elimination of DDT use due to health concerns, increased pesticide resistance among insects, and increased international travel helped fuel a resurgence of bedbug infestations. Bedbug outbreaks around the world now routinely make news headlines, such as the infestation in Paris hotels before the summer 2024 Olympic Games.

To better understand the genetics of the bedbug, Castoe and Francioli, along with researchers from Virginia Polytechnic Institute and State University, the University of Arkansas, the Dana-Farber Cancer Center, Harvard Medical School, and the Broad Institute of Massachusetts Institute of Technology and Harvard University, obtained a sample specimen of the insect and flash froze it to allow its DNA to be extracted.

From that extraction, the team was able to create a chromosome-level reference genome for the insect using PacBio long-read and Omni-C proximity genetic sequencing tools. This approach, combined with sampling additional male and female individuals, allowed the team to map a contiguous bedbug genome with 15 chromosomes (13 autosomes and two sex chromosomes: X1 and X2), providing a comprehensive genetic map that enhances our understanding of the pest’s biology, evolution and insecticide resistance.

Specifically, the identification of the sex chromosomes will help researchers understand the genetic basis of sex determination in bedbugs. This can be particularly useful for developing targeted pest control strategies that exploit sex-specific traits.

“The creation of a chromosome-level reference genome gives us a new and highly accurate contiguous map of the bedbug's genetic material,” said Castoe. “This new foundational resource will allow researchers to further understand the genetic basis of traits for the insect that cause issues such as insecticide resistance, which is crucial for developing more effective pest control strategies.”

This research was supported by the National Science Foundation Division of Environmental Biology (DEB-1754394), startup funds from the University of Tulsa and Virginia Polytechnic Institute and State University, and the Joseph R. and Mary W. Wilson Urban Entomology Endowment. Additional funding came from a National Science Foundation Doctoral Dissertation Improvement Grant (DEB-1401747).

About The University of Texas at Arlington (UTA)

Located in the heart of the Dallas-Fort Worth Metroplex, The University of Texas at Arlington is a comprehensive teaching, research, and public service institution dedicated to the advancement of knowledge through scholarship and creative work. With an enrollment of approximately 41,000 students, UT Arlington is the second-largest institution in the UT System. UTA’s combination of outstanding academics and innovative research contributes to its designation as a Carnegie R-1 “Very High Research Activity” institution, a significant milestone of excellence. The University is designated as a Hispanic Serving-Institution and an Asian American Native American Pacific Islander-Serving Institution by the U.S. Department of Education and has earned the Seal of Excelencia for its commitment to accelerating Latino student success. The University ranks in the top five nationally for veterans and their families (Military Times, 2024), is No. 4 in Texas for advancing social mobility (U.S. News & World Report, 2025), and is No. 6 in the United States for its undergraduate ethnic diversity (U.S. News & World Report, 2025). UT Arlington’s approximately 270,000 alumni occupy leadership positions at many of the 21 Fortune 500 companies headquartered in North Texas and contribute to the University’s $28.8 billion annual economic impact on Texas.

Credit

Photo courtesy UT Arlington

Journal

Journal of Heredity

DOI

10.1093/jhered/esae071

Method of Research

Data/statistical analysis

Subject of Research

Cells

Article Title

A chromosome-level reference genome for the common bed bug, Cimex lectularius, with identification of sex chromosomes

Shrubs can help or hinder a forest’s recovery after wildfire

Timing of tree replanting is key to its success

University of California - Davis

Pine tree among shrubs — image:
A young pine tree grows among shrubs in a wildfire restoration research plot in the Sierra Nevada.
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Credit: Andrew Latimer, UC Davis

Research from the University of California, Davis, is shedding light on when and where to plant tree seedlings to help restore forests after high-severity wildfires, and it has a lot to do with shrubs.

In hotter, drier areas where natural regeneration is weaker, well-timed tree planting can boost recovery by up to 200%, but the outcome also depends on competition with shrubs, a paper in the journal Forest Ecology and Management concludes.

“Generally, where there are more shrubs, the climate and soil are more hospitable for plant growth,” lead author and assistant professional researcher Derek Young said. “But what that also means is there’s more competition for trees.”

In areas where a lot of shrubs are present, it’s best to plant seedlings within a year of a wildfire to avoid competition from these woody plants. In areas with fewer shrubs, planting three years after a fire would be more effective because some of these woody plants would have grown back but not so many to consume available nutrients and water.

“Some vegetation in those really harsh sites might actually facilitate tree establishment by providing shade,” Young said.

Data-based findings

Understanding how to foster recovery is critical to restoration efforts as climate change intensifies the frequency and severity of forest fires. Land managers also must use data to help direct limited resources, said Andrew Latimer, senior author on the paper and a professor in the Department of Plant Sciences.

“We’re aiming to help optimize tree planting by targeting it to where it’s really needed,” Latimer said. “Doing this matters because we’re facing a reforestation backlog – limited capacity to replant and a lot of severely burned area.”

Look at past events

Researchers surveyed areas in the Sierra Nevada that were representative of a mix of climates and management strategies in California and had been replanted with conifer tree seedlings one to three years after intense wildfires. In each of the five 400-square-meter circular plots, which included replanted and nonplanted areas, the team counted seedlings, shrub cover and other environmental details.

This allowed researchers to gauge how replanting affects the composition of forests and map out the best strategies across wide swaths of land that would be challenging to survey on foot.

“I think the real benefit is being able to make those predictions across a huge landscape,” Young said. “Now we have quantified the effects of certain environmental variables that allow us to make those maps.”

Latimer is experimenting to see how removing shrubs two years after a fire affects tree regeneration. Young will soon use aerial imagery and drones at wildfire sites to determine how management actions affected forests in the 40 years since the trees burned.

Quinn Sorenson, who was in Department of Plant Sciences at the time of the analysis also contributed to the research, which was funded by the Joint Fire Science Program and the U.S. Department of Agriculture’s Hatch Project.