New Fossil Discoveries Indicate Asian Forest Tortoise Ancestors Evolved in Europe

Paleontologists from the Institute of Paleontology of the Polish Academy of Sciences and the Autonomous University of Barcelona have identified a new species within the genus Turtle, known as Manuria. This discovery is based on fossilized remains found in the Czech Republic.



Life restoration of Manulia morula. Image credit: Rudolf Hima.

Manulia morula thrived in the wetlands of what is now the Czech Republic during the early Miocene epoch, roughly 20 to 17 million years ago.

This species is recognized as the oldest member of Manuria, which currently exists solely in Southeast Asia and comprises four extinct species along with two living ones: Manulia Emmis and the impressed turtle (Manulia Impreza).

Tortoise paleontologist Dr. Milan Kraust from the Institute of Paleontology of the Polish Academy of Sciences remarked, ‘Turtles of the family Testudinidae are a clade highly specialized for terrestrial environments, predominantly inhabiting semi-arid conditions.’

“Members of the Testudinidae family, with carapace lengths ranging from 35 to 75 cm (14 to 30 inches), are categorized as medium to large-sized turtles, while those exceeding 75 cm are classified as giant-sized turtles.”

“Extant species of the Testudinidae can be divided into three main groups: gophers and Manuria (which appears as a basal genus or continuous branch), geokerona clade, and test duna clade, with the latter two forming the subfamily Testudininae.”

The fossil remains of Manulia morula include parts of the carapace and plastron, along with numerous unidentified shell fragments, which were uncovered at the Arnikov I fossil site in the Most Basin of Bohemia.

The length of the turtle’s shell is estimated to have been around 50 cm (20 inches).

“The Anikov I area has long been recognized as a region where wetlands featuring flooded rivers and shallow lakes have been documented,” the paleontologists stated.

“The wetland habitat near the coast was also inferred from the abundance of juvenile crocodiles and potentially the presence of Coristodere.”

“However, based on research findings regarding this genus, Manuria suggests a humid forest of evergreen broad-leaved trees situated near water, characterized by a rainy season and a distinct drier, cooler season, reminiscent of the current Kaeng Krachan National Park in Thailand.”

The discovery of Manulia morula broadens the paleobiogeographical distribution of this genus, Manuria, extending its range from Asia into the heart of Europe.

“According to our findings, the genus Manuria originated in Europe just prior to the Miocene climate optimum, subsequently spreading to Asia, where it continues to thrive today,” the researchers elaborated.

These findings were published on October 3, 2025, in the Swiss Journal of Paleontology.

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M. Kraust et al. 2025. Manulia morula sp. Nov.: An ancient large turtle from a Miocene swamp in Anikov, Czech Republic. Swiss Journal of Paleontology 144, 63; doi: 10.1186/s13358-025-00400-6

Source: www.sci.news

Forest Bathing: A Boost for Both Mental Wellness and Physical Health

Scientists have discovered further reasons to embrace nature

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It’s well established that “forest bathing” offers numerous psychological benefits, like alleviating stress and anxiety, but recent studies indicate that it may also help in lowering blood pressure and reducing inflammation, thereby enhancing physical health.

This practice, known as Shinrin Yoku, entails deep breathing and immersing oneself in nature while being aware of the surrounding sights, sounds, and scents.

Iwao Uehara from Tokyo University of Agriculture and his team aimed to delve deeper into the advantages of this practice by studying 36 adults aged between 60 and 80 who had high blood pressure.

Out of these, 24 participants engaged in a soothing hike lasting about 3.5 hours each day over the course of three days and two nights in the tranquil Qianjiangyuan National Park, China. They also took part in a one-hour guided mindfulness meditation session.

Additionally, they participated in Qigong, a traditional Chinese exercise characterized by slow, deliberate movements, along with a daily hour-long tea ceremony, enhancing their overall experience of forest bathing.

The researchers assigned 12 participants to urban living conditions, where they engaged in similar walking activities near their hotel and partook in a day-long group mindfulness meditation.

Both groups adhered to the same activity and sleep schedules and consumed identical meals, while the use of electronic devices, smoking, alcohol, and caffeine was forbidden during the study.

Heart rate, blood pressure, and C-reactive protein levels—a marker of inflammation—were measured in all participants before and after the intervention.

Results showed that those in the forest bathing group exhibited significantly reduced blood pressure and C-reactive protein levels in comparison to their urban counterparts. Additionally, a marked increase in heart rate variability was observed, which is associated with heart health. Higher scores correlate with better heart health.

“Forest therapy is a cost-effective and sensible treatment option for individuals with high blood pressure,” states Uehara. Researchers theorize that forest bathing may help soothe the nervous system and improve heart and circulatory health.

The forest group also reported notable decreases in anxiety and stress, along with enhanced energy levels compared to the urban group.

However, Julia Goffke of Virginia Tech pointed out that the study did not track the number of steps taken by the groups, suggesting that greater mobility among the forest bathing participants could explain some of the improved outcomes.

Nonetheless, the findings reinforce previous evidence that “being in a forest environment lessens stress-induced physiological and emotional reactions,” adds Gohlke.

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Source: www.newscientist.com

Paleontologists Discover New Extinct Species of Forest Wallabies

Paleontologists from Australia have unveiled fossilized remains of a new species within the extinct kangaroo genus Docopseud.

Greater Forest Wallaby (Dorcopsis Hageni). Image credit: Melvin Toullec/CC by-sa 4.0.

The newly identified species is part of the tribe Dokopshini, which currently includes six species of New Guinea forest wallabies.

However, this group has a fragmented fossil record that starts in the Australian mainland during the late Miocene epoch.

To date, two additional species of fossil forest wallabies have been described: Dorcopsoides buloloensis from the early Pliocene in southeastern Australia and Docopseudofossil from the late Miocene Alcuta Formation on the continent.

The new species, Dorcopsoides cowpatensis, is smaller than its relatives and exhibits varying combinations of dental characteristics and skeletal conditions.

“New Guinea forest wallabies are not well-known scientifically, and there is limited fundamental information regarding their diet and habitat,” noted Professor Gavin Prideaux of Flinders University.

“The existing forest wallabies are adorable and unique, featuring a slightly melancholic, whippet-like visage.”

“Their robust, curved tails function similarly to those of grey kangaroos, aiding in slow movements, almost acting as a fifth limb.”

The fossil of Dorcopsoides cowpatensis was unearthed at Kaupat Hill in the Alkuta Station of the Northern Territory.

“Forest wallabies likely migrated from Australia to New Guinea around 12 million years ago, disappearing from Australia for reasons still unclear over the past five million years,” remarked Dr. Isaac Kerr of Flinders University.

“During this time, low sea levels regularly connected the islands of New Guinea and mainland Australia, rather than being separated by the currently flooded Torres Straits.”

“Thus, early Australian mammals ventured into New Guinea’s rainforests.”

“However, once the Torres Strait was submerged again, these animal populations became isolated from their Australian counterparts, which did not endure the severe aridity characteristic of most of Australia.”

“Although Dorcopsoides cowpatensis shares many traits with contemporary forest wallabies, it inhabited remarkably different ecosystems.”

“Its environment comprised dry, scrubby bushes surrounded by thick forests, extensive marshes, and ephemeral streams and lakes.”

“These species are believed to have made quick, albeit brief, transitions from dense foliage to more open regions, foraging on leaves, fruits, and fungi.”

Research results were published in Alcheringa, the Australian Journal of Palaeontology.

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Isaac Kerr & Gavin J. Prideaux. New fossil kangaroo species of the genus Docopseud (Macropodina, Macropodinae) from the Onyeba Regional Fauna in the Late Miocene, Central Australia. Alcheringa published online on July 30th, 2025. doi:10.1080/03115518.2025.2521772

Source: www.sci.news

No Carbon Offset Programs Established Due to Forest Fires

Wildfires raging in the Amazon rainforest

Fernando Lessa/Alamy

Numerous forest-related carbon offset initiatives certified by Verra, the largest carbon registry globally, face potential risks from wildfires and other disturbances that may hinder effective carbon release from the atmosphere.

These forest-based carbon offset initiatives aim to conserve or restore forests to produce carbon credits, which can be sold to corporations or individuals to mitigate greenhouse gas emissions. Such schemes are designed to maintain a “buffer pool” of unsold carbon credits as insurance against future carbon losses due to factors like wildfires, pests, or severe weather events. Nevertheless, assessments of these buffer pools indicate that current carbon offset strategies are likely not sufficiently secured.

“The figures don’t really rely on scientific evidence, as far as we know,” stated William Anderegg from the University of Utah. A spokesperson from Verra defended the organization’s methodology, asserting that the determination of buffer pool size is grounded in rigorous, science-based risk evaluations, stressing that replenishment should align with what buffer-immersed projects have collected.

Buffer pools pose a significant challenge, especially when forest-based carbon credits are sold to offset emissions from fossil fuels that may have been in the atmosphere for centuries. “If you’re attempting to sequester carbon into trees, you need to guarantee its stability over an extended period,” Anderegg remarked.

In principle, by safeguarding adequate carbon to counterbalance potential losses over decades, a large buffer pool would suffice. However, previous research by Anderegg and his team revealed that forest carbon projects certified by Verra typically secured only 2% of their credits for protection against natural risks.

To evaluate whether this is an adequate safeguard, Anderegg and his colleagues employed ecological models to calculate the necessary size of the buffer to effectively manage the risk posed by natural disturbances across various tropical forest types. They juxtaposed these findings with the buffer pools currently mandated for Verra certification.

The results indicated that Verra’s standards fall short of ensuring permanent carbon storage in nearly all scenarios. In certain instances, the required buffer could be 11 times smaller than necessary. “Given these natural hazards, [the buffer] should be at least doubled, if not more, to be fitting,” Anderegg noted.

A Verra representative mentioned that the majority of the 76 million carbon credits presently within the buffer pool are utilized. They added, “previous reversals suggest that the buffer is not overwhelmed.” “The ongoing maintenance of buffer pools over time clearly demonstrates their effectiveness despite the risk of reversals,” the spokesperson stated.

Buffer pools are not merely a concern for Verra. For instance, California’s regulated carbon offset program has faced wildfires in recent years. A significant portion of the buffer pool was designed to endure for a century.

This concern is anticipated to grow as forest carbon losses escalate. “To secure sustainability extending beyond 100 years, you must ensure that the buffer is sufficiently robust to confront multiple climate variations,” Anderegg concluded.

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Source: www.newscientist.com

Forest Crisis Sparks Europe to Reassess Net Zero Goals

Extreme weather and bark beetles have devastated many trees in the Harz Mountains, Germany

Rob Cousins/Alamy

The abrupt and significant drop in carbon absorption by European forests has ignited concern among scientists, who fear that a marked decline could hinder efforts to combat global warming.

For many years, European forests, which span around 40% of the continent’s land area, have played a dual role as sources of timber and as carbon sinks. However, increasing extreme weather events are pushing these forests beyond their limits, swiftly altering the landscape.

“Many [European Union] countries will struggle to meet their [land-use climate] targets due to this sink reduction,” states Glen Peters from the Cicero International Climate Research Centre in Norway.

Earlier this year, Finnish officials revealed that their forest ecosystem had shifted from functioning as a net carbon sink to becoming a net carbon source. This development follows Germany’s declaration that its forests became the first in the country’s history to record a net increase in carbon emissions. Additionally, the Czech Republic has reported its forests as net carbon sources since 2018.

While these instances are particularly severe, carbon absorption rates are dwindling rapidly in many other nations. For instance, in France, the carbon uptake by forests has nearly halved in just 14 years, with a study released last month documenting a decrease from a peak of 37.8 million tonnes of carbon dioxide annually in 2008 to 74.1 million tonnes in 2022. Concurrently, Norway’s carbon absorption has plummeted from 32 million tonnes in 2010 to 18 million tonnes in 2022.

“The trend had remained relatively stable from 2013 to 2015,” comments Korosuo at the European Commission’s Joint Research Centre in Belgium. “This is a widespread issue, not confined to just one or two countries. Similar patterns are observable across nearly all forested nations.”

Many forests in Europe are privately owned and commercially managed. Some of the decrease in carbon sinks has been linked to increased logging, particularly following the sanctions on Russian timber imports due to the invasion of Ukraine in 2022. For example, Finland has seen strong demand for wood, leading to heightened harvesting levels, notes Raisa from the Natural Resources Institute of Finland.

However, scientists also attribute the rapid decline in carbon storage to the escalating impacts of climate change.

Europe has faced several droughts in recent years, with 2018 and 2022 marking the harshest conditions. Wouter Peters at Wageningen University in the Netherlands highlights that his research indicates the 2022 drought caused a significant reduction in carbon intake by European forests during summer months. “We’re observing immediate effects; the trees are under stress,” he comments.

Researchers had expected that as global temperatures rise, European forests would diminish in health, yet the extent of the recent decline is still astonishing. Wouter Peters explains, “The impact seems to be more severe than anticipated.”

This downturn could be a result of successive droughts occurring within a few years, exacerbated by other extreme weather events such as storms that disturb forests. “We see not just one drought in 2018, but additional ones in 2021 and 2022,” Wouter Peters notes. “Our models have not effectively accounted for this concentration of drought events over such a short time frame.”

Moreover, rising temperatures are leading to more frequent and widespread infestations of bark beetles across Europe, which are severely damaging spruce forests. The Czech Republic, in particular, has faced seven major bark beetle outbreaks from 2018 to 2021.

A declining carbon sink poses a threat to the EU’s climate objectives, which depend on forests to absorb the bulk of emissions generated by other sectors. The EU is even aiming to enhance this carbon sink to support its climate ambitions, targeting a removal of 310 million tonnes of CO2 equivalents annually by 2030, a significant increase from the approximately 230 million tonnes currently removed.

However, a recent analysis published in April warns that European carbon sinks are projected to decrease by around 29% below the 2030 target, with researchers cautioning that the capability of European forests to absorb carbon will “gradually deteriorate.”

Preventative measures can help mitigate this decline, such as reducing harvesting rates and prohibiting clear-cutting in plantations, which can maintain carbon stocks. Additionally, increasing species diversity and retaining some deadwood can enhance forest health and resilience against pests and droughts.

Nonetheless, Wouter Peters argues that policymakers are overestimating the carbon absorption potential of forests in warmer climates. “There has likely been an over-reliance on forests, particularly in the context of greenhouse gas emissions,” he contends. He emphasizes that other sectors must rapidly reduce emissions to meet European climate goals. “This implies that we need intensified efforts in other areas.”

Carbon dioxide levels in the atmosphere are rising at unprecedented rates, despite an overall stagnation in greenhouse gas emissions. Scientists attribute this acceleration to slower carbon absorption rates in forests, wetlands, and peatlands globally, compounded by deforestation and increased emissions from wildfires and droughts that weaken global land sinks.

This issue is most pronounced in mid-latitude regions. Alongside Europe, significant declines in carbon sink capacity have also been recorded in boreal forests of Alaska and Canada. Tropical forests are facing challenges from both deforestation and diminished carbon storage capacity, primarily due to wildfires.

This poses a serious challenge to global efforts to achieve net-zero emissions. “In a broad global context, the entire concept of net zero hinges on the functionality of forests and oceans. If these systems cease to effectively sequester carbon, it will lead to increased atmospheric carbon levels and accelerated global warming.”

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Source: www.newscientist.com

Tropical Forest Losses Soared in 2024 Amidst Surge in Wildfires

Forests have been cleared for mining in the Brazilian Amazon

Marcio Isensee e Sá/Getty Images

In 2024, the loss of tropical forests reached unprecedented levels, doubling the rate seen in the last two decades, primarily due to climate change making rainforests more vulnerable to uncontrollable fires.

A comprehensive annual analysis of satellite imagery conducted by Global Forest Watch and the University of Maryland revealed a staggering loss of 67,000 square kilometers of crucial tropical rainforests in 2024. Primeval forests, defined as mature woodlands that have not been subjected to logging, were particularly affected.

The report’s author indicated that the dramatic increase in forest loss can be largely attributed to the El Niño weather phenomenon alongside global warming, which has exacerbated conditions leading to catastrophic fires in rainforests.

“We don’t just have agricultural activities as the main cause of deforestation,” stated Rod Taylor from Global Forest Watch, an initiative of the World Resources Institute. “This new amplification effect constitutes a genuine climate change feedback loop, with fires becoming increasingly intense and destructive.”

Tropical forests play a vital role in regulating weather patterns, sequestering carbon, and cooling the planet. However, recent trends in deforestation have led to them releasing more carbon than they absorb, pushing them toward a critical tipping point.

The report also reveals that the area affected by wildfires in native forests during 2023 was five times greater than the losses registered in 2023, constituting 48% of all primary rainforest losses.

Globally, wildfires emitted greenhouse gases equivalent to 4.1 gigatonnes of carbon dioxide last year, significantly more than the total emissions from air travel in 2023.

Associated with warm and dry weather conditions in the tropics, the El Niño phenomenon officially ended in April 2024 but left lasting effects as rainforest soil and vegetation remained parched from earlier wildfires.

The context of global warming also played a significant role, making 2024 the driest year in Brazil in 70 years, as noted by Ane Alencar from the Amazon Environmental Research Institute in Belem, Brazil.

Brazil witnessed a loss of 28,000 square kilometers of its primary forest, the highest figure since 2016, accounting for 42% of all tropical native forest losses.

Fires in the Brazilian Amazon were responsible for 60% of the overall forest loss, as individuals exploited the dry conditions to clear land for agricultural purposes.

Elsewhere, countries such as Canada and Russia also reported significant wildfires beyond the tropical regions, contributing to a global forest loss of 300,000 square kilometers, a new record.

“Some experts argue that we are currently in a pyrocene, or age of fire, as opposed to the Anthropocene,” noted Erika Berenguer from Oxford University.

While bushfires pose a serious threat, Berenguer cautioned that the statistics might include degradation, where some trees were lost without complete deforestation, the latter being the total clearance of forests.

“Degradation diminishes carbon storage, undermines biodiversity, and increases susceptibility to future fires, but it’s not equivalent to transforming land into soy fields or pastures,” she explained.

The report highlights how ongoing degradation and a warming climate have rendered rainforests increasingly vulnerable, according to Alencar.

“Typically, if a fire breaks out in the Amazon, you can witness some degradation, but the forest has the potential to recover,” she stated. “However, this report indicates that during extreme droughts, forests can burn intensely, fostering conditions that may lead to complete loss of the forest.”

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Source: www.newscientist.com

Experience the Healing Benefits of Forest Bathing for Better Health – Here’s How

Forest bathing is an ancient Japanese therapeutic technique dating back to the 1980s. It involves spending restorative time in forests and natural environments to connect with nature and achieve sensory relaxation. Despite sounding like hippie nonsense, there is scientific evidence emerging that supports the benefits of forest bathing.

This practice does not involve any nudity or water activities; instead, it encourages mindfulness, disconnecting from technology, light exercise, and escaping the sensory overload of the modern world. Research has shown that spending time in nature can have a positive impact on mental and physical health, reducing blood pressure, cortisol levels, and heart rate.

Studies on green space exposure have demonstrated significant improvements in various health markers, such as lower rates of diabetes, cardiovascular disease, and mortality. Forest bathing is taken seriously in Japan and South Korea, where doctors prescribe it as a therapeutic intervention for stress and hypertension.

A UK study on forest bathing led by Dr. Kirsten McEwan has shown promising results, including a 12% improvement in heart rate variability and enhanced mood. The mechanism behind these health benefits is believed to involve the stimulation of the parasympathetic nervous system and the release of chemicals by trees that boost the immune system.

Nature’s impact on long-term health outcomes is still being studied, but initial findings suggest that spending time in nature can have significant health benefits. Perhaps Western medicine is beginning to recognize and embrace the benefits of traditional practices like forest bathing, aligning with generations of knowledge that being outside in nature is good for overall well-being.

About our experts

Dr. Kirsten McEwan, Associate Professor of Health and Wellbeing at the University of Derby, is leading research on forest bathing through the Forest Therapy Hub.

Source: www.sciencefocus.com

Forest plantations may not provide as many climate benefits as previously thought

Planting trees helps reduce global warming

PG Alfexado / Alamy

Planting forests helps reduce further global warming by absorbing some of the carbon dioxide we emit into the atmosphere. But the global climate benefit could be about 15 to 30 percent smaller than previously estimated, due to other influences such as sunlight absorption by trees.

“We're not saying don't plant trees,” he says. james webber at the University of Sheffield, UK. It's just that the climate benefits aren't as big as we thought, he says.

The impact of trees will depend in part on what other actions are taken to address climate change. Weber and his colleagues showed that the more forests are planted, the greater the benefits. “It’s more positive and efficient to do other things at the same time,” he says.

It has long been known that plants have both warming and cooling effects. In particular, dark foliage can have a warming effect by absorbing light that would otherwise be reflected into the space. This effect is strongest when trees are replaced by snow or ice, but can occur in other situations as well.

Plants also release volatile organic compounds into the air. “Those are the chemicals that create the smell of the forest,” team members say james king also at the University of Sheffield.

These biogenic compounds can affect the climate in a variety of ways. One important example is that it can react with chemicals in the atmosphere that react with methane. “So the methane stays around longer, and methane is a powerful greenhouse gas,” Weber said.

Compounds emitted by plants can also react with nitrogen oxides to form ozone, another greenhouse gas.

These effects will lead to further warming. However, compounds of biological origin can also form aerosol particles that reflect sunlight and have a cooling effect.

To understand the overall climate impact of afforestation, the researchers incorporated these and other processes into a climate model in which all available land is forested. This means, for example, trees that are located in areas that are currently grasslands, but not in farmland or urban areas.

“To our knowledge, this is the first time this has been done on a global scale and based on a plausible reforestation scenario,” King said.

The researchers modeled two scenarios. For one, little is being done to tackle climate change other than planting trees. In this case, the warming avoided by CO2-absorbing forests is reduced by 23 to 31 percent, once other forest impacts are taken into account.

In the second, more optimistic scenario, strong action is taken to limit further warming. In this case, avoided warming was reduced by 14 to 18 percent.

One reason for the difference is that reducing fossil fuel emissions reduces aerosols from air pollution. In a polluted world, adding more aerosols from forests won't make much of a difference, but in a cleaner world, the cooling effect will be greater.

The team acknowledges that the model is still incomplete and does not include all feedback effects. For example, it includes the greenhouse effect of ozone, but not its effects on vegetation. High levels of ozone can kill trees, meaning less CO2 is removed from the atmosphere. The model also does not include the effects of wildfires.

“It's very complicated,” King says. “It's not really possible to consider all feedback in one study.”

“Importantly, this study shows that preventing deforestation is a much more efficient way to mitigate climate change compared to reforestation, and therefore should be prioritized. It’s a necessity,” he says. Stephanie Law Climate Scientist at WWF in Washington, DC.

Another feedback missing from the model is the cooling effect of water evaporating from leaves, which can be greater in tropical regions, Roe says. So the climate benefits of tree planting may be overestimated, she says, but the study doesn't yet tell the full story.

Additionally, tree planting has many other benefits for humans and wildlife, including reducing erosion, maintaining water supply and quality, providing food and jobs, and reducing extreme heat in the region. “Afforestation, especially reforestation in forest biomes with native species, is absolutely worth pursuing,” says Lo.

“We've always known that forests have a warming effect under certain conditions and a cooling effect under others. What this study shows is that forests have an overwhelming net The effect is a cooling effect.” thomas crouser in ETH Zurich Swiss.

“But most importantly, even if the effects of cooling were not as great, we still need to conserve our natural forests to support the planet's biodiversity and the billions of people who depend on it.” “There is,” he says.

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Source: www.newscientist.com

Recent study challenges previous beliefs about forest resilience

Recent research has shown that trees in humid regions are more vulnerable to drought, challenging previous beliefs about tree resilience. The study, which included analysis of more than 6.6 million tree rings, revealed that trees in arid regions are surprisingly drought tolerant. This finding highlights the widespread effects of climate change on forests and suggests that genetic diversity in drier regions may be important for adapting to changing conditions. There is. Credit: SciTechDaily.com

Scientists have flipped the script and revealed that trees in humid regions are more sensitive to drought.

This holiday season brings some surprising news about Christmas trees. Scientists have found that globally, trees that grow in wetter regions are more sensitive to drought. This means that if your tree was grown in a humid climate, it has likely been damaged over generations.

Debate over drought tolerance of trees

Scientists have long debated whether arid environments make trees more or less tolerant of drought. It seems intuitive that trees living at the biological margin are most vulnerable to climate change. Because even the slightest bit of extra stress can send a tree over the brink. On the other hand, these populations may be better able to withstand drought because they are adapted to harsher environments.

The trees of this lush temperate forest in the Cascade Mountains of Washington state may be less drought tolerant than trees in drier regions of the South.Credit: Joan Dudney

Insights from new research

According to a new study published in the journal science Increased water availability could “kill” trees by reducing their ability to adapt to drought, according to researchers from the University of California, Santa Barbara and the University of California, Davis. “And that’s really important to understand when we think about the global vulnerability of forest carbon stocks and forest health.” said Joan Dudney, an assistant professor and ecologist. “You don’t want to be a ‘spoiled’ tree when faced with a major drought.”

Dudney and his co-authors predicted that trees growing in the driest regions would be more sensitive to drought because they were already living on the edge of their limits. Furthermore, climate change models predict that these regions will dry out more rapidly than wetter regions. This change in climate can expose trees to conditions beyond their ability to adapt.

Methodology: Tree ring analysis

To measure drought sensitivity, the authors analyzed 6.6 million tree ring samples from 122 trees. seed World wide. They measured whether a tree was growing faster or slower than average based on the width of its growth rings. They correlated these trends with historical climate data such as precipitation and temperature.

The team then compared different regions’ responses to drought. “As you move to the drier edge of a species’ range, trees become less and less sensitive to drought,” said lead author Robert Heilmeyer, an environmental economist with the Environmental Research Program and the Bren School. he said. “Those trees are actually very resilient.”

Dudney, Heilmeyer, and their co-author Frances Moore were partially inspired by UCSB professor Tamma Carleton’s research on the effects of climate change on humanity. “This paper highlights the value of interdisciplinary scientific research,” added Moore, an associate professor at the University of California, Davis. “We applied economics methods originally developed to study how people and businesses adapt to changing climate, and applied them to ecological contexts to study the sensitivity of forests to drought. could be applied to.”

“A heat wave is likely to kill more people in a cool place like Seattle than in a hot city like Phoenix,” Heilmeyer said. It’s already quite hot in the Southwest, with a scorching heatwave occurring. But cities in the region are adapted to extreme climates, he points out. We now know that forests exhibit similar trends.

Impact on warm regions

Unfortunately, temperate regions are expected to become disproportionately drier in the coming decades. “Significant parts of the species’ ranges will be faced with entirely new climates, a phenomenon that these species do not find anywhere else in their ranges today,” Heilmeyer explained. The authors found that in 2100, 11% of the average species’ range will be drier than the driest part of its historical range. For some species, this increases to 50% or more.

“Broadly speaking, our study highlights that very few forests will be immune to the effects of climate change,” Dudney said. “Even wet forests are under more threat than we realize.”

But there’s also the other side of the coin. This species stores drought-tolerant resources in drier parts of its range and has the potential to strengthen forests in wetter regions. Previous research UCSB researchers have revealed that many species have the ability to adapt to environmental changes. But these researchers also discovered that trees move slowly from one generation to the next. This means that human intervention, such as assisted migration, may be required to take advantage of this genetic diversity.

Christmas tree and the fate of the forest

Whether the Christmas tree lives in a dry or humid region, its growth may decrease in the future. But understanding how trees respond to climate change can help secure the future of Tannenbaum and its wild trees.

Reference: “Drought sensitivity of mesic forests increases vulnerability to climate change” by Robert Heilmeyer, Joan Dudney, and Frances C. Moore, December 7, 2023. science.
DOI: 10.1126/science.adi1071

Source: scitechdaily.com