Saturday, November 26, 2022

Researchers from Gwangju Institute of Science and Technology develop an intelligent observer for Esports

It utilizes an object detection algorithm that learns human spectating data to find engaging viewports

Peer-Reviewed Publication

GIST (GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY)

GIST researchers develop and intelligent observer to enhance Esport spectator experience 

IMAGE: AN ARTIFICIAL OBSERVER WILL INTERACT WITH COMMENTATORS WHILE ANALYZING REAL-TIME IN-GAME STATE FOR THE BEST SPECTATOR EXPERIENCE. view more 

CREDIT: KYUNG-JOONG KIM

Esports, already a billion-dollar industry, is growing, partly because of human game observers. They control the camera movement and show spectators the most engaging portions of the game screen. However, these observers might miss significant events occurring concurrently across multiple screens. They are also difficult to afford in small tournaments. Consequently, the demand for automatic observers has grown. Artificial observing methods can either be rule-based or learning-based. Both of them predefine events and their importance, necessitating extensive domain knowledge. Moreover, they cannot capture undefined events or discern changes in the significance of the events.

Recently, researchers from South Korea, led by Dr. Kyung-Jong Kim, Associate Professor in Gwangju Institute of Science and Technology, have proposed an approach to overcome these problems. “We have created an automatic observer using object detection algorithm, Mask R-CNN, to learn human spectating data,” explains Dr. Kim. Their findings were made available online on 10 October 2022 and published in Volume 213 Part B of Expert Systems with Applications journal.

The novelty lies in defining the object as the two-dimensional spatial area viewed by the spectator. In contrast, conventional object detection treats a single unit, for instance, a worker or a building, as the object. In this study, the researchers first collected StarCraft in-game human observation data from 25 participants. Next, the viewports—areas viewed by the spectator—were identified and labeled as “one.” The rest of the screen was filled with “zeroes.” While the in-game features are used as input data, the human observations constituted the target information.

The researchers then fed the data into the convolution neural network (CNN), which learnt the patterns of the viewports to find the “region of common interest” (ROCI)—the most exciting area for the spectators to watch. They then compared the ROCI Mask R-CNN approach with other existing methods quantitatively and qualitatively. The former evaluation showed that CNN’s predicted viewports were similar to the collected human observational data. Additionally, the ROCI-based method outperformed others in the long run during the generalization test, which involved different matchup races, starting locations, and playing maps. The proposed observer was able to capture the scenes of interest to humans. In contrast, it could not be done by behavior cloning—an imitation learning technique.

Dr. Kim points out the future applications of their work. “The framework can be applied to other games representing some of the overall game state, not only StarCraft. As services such as multi-screen transmission continue to grow in Esports, the proposed automatic observer will play a role in these deliverables. It will also be actively used in additional content developed in the future.”

 

***

 

Reference

DOI: https://doi.org/10.1016/j.eswa.2022.118979

 

Authors: Ho-Taek Joo1, Sung-Ha Lee2, Cheong-mok Bae1, Kyung-Joong Kim1,2

 

Affiliations:     

1School of Integrated Technology, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, South Korea

2AI Graduate School, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, South Korea

 

About the Gwangju Institute of Science and Technology (GIST)
The Gwangju Institute of Science and Technology (GIST) is a research-oriented university situated in Gwangju, South Korea. Founded in 1993, GIST has become one of the most prestigious schools in South Korea. The university aims to create a strong research environment to spur advancements in science and technology and to promote collaboration between international and domestic research programs. With its motto of “A Proud Creator of Future Science and Technology,” GIST has consistently received one of the highest university rankings in Korea.

Website: http://www.gist.ac.kr/

 

About the author
KYUNG-JOONG KIM (Member, IEEE) received the B.S., M.S., and Ph.D. degrees in computer science from Yonsei University, in 2000, 2002, and 2007, respectively. He worked as a Postdoctoral Researcher with the Department of Mechanical and Aerospace Engineering, Cornell University, in 2007. He is currently an Associate Professor with the School of Integrated Technology, Gwangju Institute of Science and Technology (GIST). His research interests include artificial intelligence, game, and robotics.

 

Funding Information:
This research was supported by the National Research Foundation of Korea (NRF) funded by the MSIT (2021R1A4A1030075).

Wireless smart bandage provides new insights on healing chronic wounds

A new type of bandage combines wireless electrical stimulation and biosensors to bring hope to patients with slow-to-heal injuries.

Peer-Reviewed Publication

STANFORD WEARABLE ELECTRONICS INITIATIVE

Wireless smart bandage 

IMAGE: DRAWING OF WIRELESS SMART BANDAGE ON HUMAN ARM view more 

CREDIT: JIAN-CHENG LAI, BAO RESEARCH GROUP @ STANFORD UNIVERSITY

By Andrew Myers

Some wounds just won’t heal. Infections, diseases like diabetes, and suppressed immune systems often stack up to slow healing. Chronic wounds can last months and lead to anxiety and depression. In the worst cases, they are life threatening. Cost of treatment has soared to $25 billion each year.

So far, however, solutions for treating chronic wounds have been few and far between, but researchers at Stanford University now report that they have developed a wireless smart bandage that has shown promise in speeding up tissue repair by monitoring the wound healing process and treating the wound simultaneously. The researchers say in a paper published November 24th in Nature Biotechnology that their device promotes faster closure of wounds, increases new blood flow to injured tissue, and enhances skin recovery by significantly reducing scar formation.

The smart bandage is composed of wireless circuitry that uses impedance/temperature sensors to monitor the progression of wound healing. If the wound is less healed or an infection is detected, the sensors inform a central processing unit to apply more electrical stimulation across the wound bed to accelerate tissue closure and reduce infection. The researchers were able to track the sensor data in real time on a smart phone, all without the need for wires.

Engineering marvel

The electronic layer, including a microcontroller unit (MCU), radio antenna, memory, electrical stimulator, biosensors, and other components, is just 100 microns thick—about the thickness of a single coat of latex paint.

All that circuitry rides atop a cleverly engineered hydrogel—a rubbery, skin-like polymer—that is integrated to both deliver healing electrical stimulation to the injured tissue and collect real-time biosensor data.

The polymer in the hydrogel is carefully designed to adhere securely to the wound surface when needed, yet to pull away cleanly and gently without harm to the wound when warmed to just a few degrees above body temperature (40°C/104°F).

“In sealing the wound, the smart bandage protects as it heals,” says Yuanwen Jiang, co-first author of the study and a post-doctoral scholar in the lab of Zhenan Bao, the K.K. Lee Professor in Chemical Engineering in the Stanford School of Engineering. “But it is not a passive tool. It is an active healing device that could transform the standard of care in the treatment of chronic wounds.”

Electrical stimulation, also known as galvanotaxis, has been previously reported to accelerate the migration of keratinocytes to the wound site, limit bacterial infections and prevent the development of biofilms on wound surfaces, to proactively promote tissue growth and help with tissue repair. The researchers were able to take this well-studied technology and integrate it with real-time biosensor data to provide a novel automated treatment modality that is informed by biosensors.

The smart bandage’s biosensing capabilities monitor biophysical changes in the local environment, providing a real-time, rapid, robust, and extremely accurate way to measure wound condition. Technically speaking, the smart bandage senses conductivity and temperature changes in the skin as the wound heals—electrical impedance increases as wounds heal and local temperatures decline as inflammation subsides. “With stimulation and sensing in one device, the smart bandage speeds healing, but it also keeps track as the wound is improving,” says Artem Trotsyuk, likewise a co-first author of the study who completed his graduate work in the lab of Geoffrey Gurtner, MD, formerly the Johnson & Johnson Distinguished Professor of Surgery (Emeritus) in the Stanford School of Medicine, and currently the Chair of the Department of Surgery and Professor of Biomedical Engineering at the University of Arizona in Tucson. “We think it represents a new modality that will enable new biological discovery and the exploration of previously difficult-to-test hypotheses on the human healing process.”


Welcome results, new directions

The researchers took their study a step further, venturing to understand why and how electrical stimulation heals the wound faster. They now believe that electrical stimulation promotes the activation of pro-regenerative genes such as Selenop, an anti-inflammatory gene that has been found to help with pathogen clearance and wound repair, and Apoe, which has been shown to increase muscle and soft tissue growth. Likewise, electrical stimulation increased the amount of white blood cell populations, namely monocytes and macrophages, through the recruitment of greater amounts of M2 anti-inflammatory macrophages, which have been previously reported as pro-regenerative and playing a key role in the extracellular matrix formation that is required during the proliferative phases of wound healing.

The researchers caution that the smart bandage is, as yet, a proof of concept, albeit a promising one. Many challenges remain, however. These include increasing the size of the device to human scale, reducing cost, and solving long-term data storage issues - all necessary to scale up to mass production should need and opportunity arise. Likewise, there are potentially new sensors not currently integrated that might be added, such as those that measure metabolites, biomarkers, and pH. And there are some potential roadblocks to clinical use, such as hydrogel rejection, in which the skin may react to the device and create a bad gel-to-skin combination, or biofouling of the sensors, which can cause irritation.

Despite these hurdles, the researchers are pushing ahead and remain optimistic about the potential of their smart bandage to provide hope for patients suffering with chronic wounds.

Stanford co-first authors: Yuanwen Jiang is a postdoctoral fellow in the Bao Group; Artem Trotsyuk is a former graduate student in the Gurtner Lab; Simiao Niu is a former postdoctoral scholar in the Bao Group.

Other Stanford co-authors: Dominic Henn, Kellen Chen, Zeshaan Maan, Melanie Rodrigues, Clark A. Bonham, Michael Januszyk, Ethan Beard, Tanish Jain, Jagannath Padmanabhan, Katharina Fischer and Sun Hyung Kwon are members of the Gurtner Lab; Alana Mermin-Bunnell, Smiti Mittal, Sydney Steele, Gurupranav Gurusankar, Christopher Neimeth, Hudson Kussie, Madelyn Larson, and Serena Jing are undergraduates in the Gurtner Lab; Dharshan Sivaraj and Melissa Leeolou are MD students in the Gurtner Lab; David Perrault and Arhana Chattopadhyay are residents in plastic surgery and are members of the Gurtner Lab; Chien-Chung Shih, Jian-Cheng Lai, Jing Tang and Donglai Zhong are postdoctoral fellows; Willian Viana and Eric Zhao are graduate students; Ronjon Nag is a Stanford Distinguished Careers Institute Fellow and an Adjunct Professor of Genetics; Michael Snyder is professor and Chair of the Genetics Department; Aref Saberi, Kefan Sun, and Kui Liang; Zhenan Bao is also a member of Stanford Bio-X, the Stanford Cardiovascular Institute, the Maternal & Child Health Research Institute (MCHRI), the Precourt Institute for EnergySarafan ChEM-HStanford Woods Institute for the Environment, the Wu Tsai Human Performance Alliance, the Wu Tsai Neurosciences Institute, and an investigator of CZ Biohub; Geoffrey Gurtner is also a member of Stanford Bio-Xthe Stanford Cardiovascular Institutethe Stanford Cancer Instituteand the Wu Tsai Neurosciences Institute and was the founding director of the Stanford Advanced Wound Care Center (AWCC). Kailiang Zhang is a Research Scientist with BOE Technology Group.

The eWEAR-TCCI awards for science writing is a project commissioned by the Wearable Electronics Initiative (eWEAR) at Stanford University and made possible by funding through eWEAR industrial affiliates program member Shanda Group and the Tianqiao and Chrissy Chen Institute (TCCI®).

A study offers new insights into the record 2021 Western North America heat wave

Combined unusual weather systems, supercharged by climate change

Peer-Reviewed Publication

COLUMBIA CLIMATE SCHOOL

Deadly Meanders 

IMAGE: HE 2021 HEAT WAVE OVER WESTERN NORTH AMERICA CAME IN PART FROM BENDING OF THE NORTHERN HEMISPHERE’S JET STREAM INTO FOUR HUGE NORTH-SOUTH PEAKS AND TROUGHS. ABOVE, REDDER COLORS INDICATE HIGHER TEMPERATURES; BLACK ARROWS SHOW WIND DIRECTIONS. UNDER THE PEAKS, WESTERN EURASIA AND NORTHEAST SIBERIA EXPERIENCED TEMPERATURE SPIKES, BUT NORTH AMERICA (INSIDE BOX) SAW THE WORST. WITHIN A FOURTH PEAK, ICELAND ALSO SAW ELEVATED TEMPERATURES. view more 

CREDIT: ADAPTED FROM BARTUSEK ET AL., NATURE CLIMATE CHANGE 2022

The heat wave that hammered western North America in late June and early July 2021 was not just any midsummer event. Over nine days, from British Columbia through Washington and Oregon and beyond, it exceeded average regional temperatures for the period by 10 degrees C (18 F), and on single days in some locales, by an astounding 30 C, or 54 F. Among many new daily records, it set a new national benchmark for all of Canada, at 121.3 F in Lytton, British Columbia. The next day, the entire town burned down amid an uncontrollable wildfire—one of many sparked by the hot, dry weather. Across the region, at least 1,400 people died from heat-related causes.

Within weeks, scientists blamed the event’s extremity largely on climate change. Now, a new study in the journal Nature Climate Change affirms that conclusion, and for the first time comprehensively elucidates the multiple mechanisms—some strictly climate-related, others more in the realm of disastrous coincidences—that they say led to the mind-bending temperatures.

“It was so extreme, it’s tempting to apply the label of a ‘black swan’ event, one that can’t be predicted,” said lead author Samuel Bartusek, a Ph.D. student at the Columbia Climate School’s Lamont-Doherty Earth Observatory. “But there’s a boundary between the totally unpredictable, the plausible, and the totally expected that’s hard to categorize. I would call this more of gray swan.”

The study pulled climate data starting in the 1950s together with daily weather observations from the weeks preceding and during the heat wave to form an intimate portrait. A core conclusion: Such an event would have been virtually impossible absent human-induced warming. It was impossible in the 1950s, but atmospheric warming since then has moved the needle to a prospective 1-in-200-year event—still rare, but now feasible. The researchers predicts that if warming continues at even a moderate pace, such heat waves could hit the region about every 10 years by 2050.

Average global temperatures have risen less than 2 degrees F in the last century. But small upward increments may shift interactions between atmosphere and land in ways that drive chances of extreme temperature spikes far beyond just the average temperature rise. Boiled down to the simplest terms, the study says much of the 2021 heat wave arose from the multiplying effects of higher overall temperatures, including drying of soils in some areas. Additionally, about a third of the heat wave came from what the researchers call “nonlinear” forces—short-term weather patterns that helped lock in the heat that may also have been amplified by changing climate.

One major driver, they say, was a disruption of the jet stream, which normally carries air west to east across the Northern Hemisphere midlatitudes along a more or less circular path. Preceding the heat wave, though, the jet stream stalled and bent into huge waves, with four north-south peaks and troughs. These concentrated high-pressure systems underneath each peak; high pressure compresses air more and more as it approaches the surface, and this generates heat. One of those systems settled on western North America, then stayed there there day after day, creating what meteorologists call a “heat dome.”

Some scientists believe big jet-stream waves are becoming more frequent and extreme due to human-induced warming. The jet stream normally forms a boundary between frigid polar air and warmer southern air, but recent outsize warming in the Arctic is breaking down the temperature difference, destabilizing the system, they say. This idea is still being debated. That said, part of the groundwork for the new study was laid by coauthor Kai Kornhuber, who published a 2019 study identifying such meanders as threats to world food security should they hit multiple major agricultural regions simultaneously. In 2021, concurrent major heat waves tied to the meanders hit not just North America, but within a dome spanning much of Scandinavia, Eastern Europe, western Russia and the Caucasus; and another over northwestern Siberia.

Western North America’s was by far the worst. One factor, the authors say, was a series of smaller-scale atmospheric waves generated in the western Pacific Ocean. These moved east, and upon hitting land, latched onto the larger jet-stream wave and amplified it. Meteorologists could see these patterns coming some 10 days out, and thus accurately warned of the heat wave well in advance.

A longer-term key factor, the researchers say, is climate-driven drying that has overtaken much of the U.S. and Canadian west in recent decades, reducing soil-moisture levels in many areas. During the heat wave, that meant reduced evaporation of water from vegetation that previously would have helped counteract heating of the air near the surface. With less evaporation, in some places the surface more effectively heated the air above it. Indeed, the researchers found that the heat wave was most extreme in areas with the driest soils.

“Global warming is gradually making the Pacific Northwest drier,” said study coauthor Mingfang Ting, a Lamont-Doherty professor, pushing it into a long-term state where such extreme events are becoming ever more likely.

Extraordinary heat and drought continue to affect the region. In mid-October of this year, many daily temperature records were shattered with spikes more characteristic of high summer than mid-autumn. These included 88 degrees in Seattle on Oct. 16—a full 16 degrees above the previous daily record. The same day, there were records in Vancouver (86); Olympia, Wash. (85); and Portland, Ore. (86), its fifth consecutive day in the 80s. The hot, dry weather has sparked forest fires so fierce and widespread that on Oct. 20, smoke caused Seattle to see the worst air quality of any big city in the world, ahead of usual favorites like Beijing and Delhi.

“We can certainly expect more hot periods in this area and other areas, just due to the increase in global temperatures, and the way it shifts the probability of extreme events by huge amounts,” said Bartusek

Hot, dry weather during the heat wave sparked numerous wildfires, destroying large areas and worsening air quality.

CREDIT

USDA photo by Kari Greer

525-million-year-old fossil defies textbook explanation for brain evolution

According to a new study, fossils of a tiny sea creature with a delicately preserved nervous system solve a century-old debate over how the brain evolved in arthropods, the most species-rich group in the animal kingdom

Peer-Reviewed Publication

UNIVERSITY OF ARIZONA

Reconstruction of the armored lobopodian Cardiodictyon catenulum 

IMAGE: ARTIST'S IMPRESSION OF AN INDIVIDUAL 525-MILLION-YEAR-OLD CARDIODICTYON CATENULUM ON THE SHALLOW COASTAL SEA FLOOR, EMERGING FROM THE SHELTER OF A SMALL STROMATOLITE BUILT BY PHOTOSYNTHETIC BACTERIA. view more 

CREDIT: NICHOLAS STRAUSFELD/UNIVERSITY OF ARIZONA

Fossils of a tiny sea creature that died more than half a billion years ago may compel a science textbook rewrite of how brains evolved.

A study published in Science – led by Nicholas Strausfeld, a Regents Professor in the University of Arizona Department of Neuroscience, and Frank Hirth, a reader of evolutionary neuroscience at King's College London – provides the first detailed description of Cardiodictyon catenulum, a wormlike animal preserved in rocks in China's southern Yunnan province. Measuring barely half an inch (less than 1.5 centimeters) long and initially discovered in 1984, the fossil had hidden a crucial secret until now: a delicately preserved nervous system, including a brain.

"To our knowledge, this is the oldest fossilized brain we know of, so far," Strausfeld said.

Cardiodictyon belonged to an extinct group of animals known as armored lobopodians, which were abundant early during a period known as the Cambrian, when virtually all major animal lineages appeared over an extremely short time between 540 million and 500 million years ago. Lobopodians likely moved about on the sea floor using multiple pairs of soft, stubby legs that lacked the joints of their descendants, the euarthropods – Greek for "real jointed foot." Today's closest living relatives of lobopodians are velvet worms that live mainly in Australia, New Zealand and South America.

A debate going back to the 1800s

Fossils of Cardiodictyon reveal an animal with a segmented trunk in which there are repeating arrangements of neural structures known as ganglia. This contrasts starkly with its head and brain, both of which lack any evidence of segmentation.

"This anatomy was completely unexpected because the heads and brains of modern arthropods, and some of their fossilized ancestors, have for over a hundred years been considered as segmented," Strausfeld said.

According to the authors, the finding resolves a long and heated debate about the origin and composition of the head in arthropods, the world's most species-rich group in the animal kingdom. Arthropods include insects, crustaceans, spiders and other arachnids, plus some other lineages such as millipedes and centipedes.

"From the 1880s, biologists noted the clearly segmented appearance of the trunk typical for arthropods, and basically extrapolated that to the head," Hirth said. "That is how the field arrived at supposing the head is an anterior extension of a segmented trunk."

"But Cardiodictyon shows that the early head wasn't segmented, nor was its brain, which suggests the brain and the trunk nervous system likely evolved separately," Strausfeld said.

The fossilized Cardiodictyon catenulum was discovered in 1984 among a diverse assemblage of extinct creatures known as the Chengjian fauna in Yunnan, China. In this photo, the animal's head is to the right.

CREDIT

Nicholas Strausfeld/University of Arizona

Brains do fossilize

Cardiodictyon was part of the Chengjiang fauna, a famous deposit of fossils in the Yunnan Province discovered by paleontologist Xianguang Hou. The soft, delicate bodies of lobopodians have preserved well in the fossil record, but other than Cardiodictyon none have been scrutinized for their head and brain, possibly because lobopodians are generally small. The most prominent parts of Cardiodictyon were a series of triangular, saddle-shaped structures that defined each segment and served as attachment points for pairs of legs. Those had been found in even older rocks dating back to the advent of the Cambrian. 

"That tells us that armored lobopodians might have been the earliest arthropods," Strausfeld said, predating even trilobites, an iconic and diverse group of marine arthropods that went extinct around 250 million years ago.

"Until very recently, the common understanding was 'brains don't fossilize,'" Hirth said. "So you would not expect to find a fossil with a preserved brain in the first place. And, second, this animal is so small you would not even dare to look at it in hopes of finding a brain.”  

However, work over the last 10 years, much of it done by Strausfeld, has identified several cases of preserved brains in a variety of fossilized arthropods.

Fossilized head of Cardiodictyon catenulum (anterior is to the right). The magenta-colored deposits mark fossilized brain structures.

CREDIT

Nicholas Strausfeld

A common genetic ground plan for making a brain

In their new study, the authors not only identified the brain of Cardiodictyon but also compared it with those of known fossils and of living arthropods, including spiders and centipedes. Combining detailed anatomical studies of the lobopodian fossils with analyses of gene expression patterns in their living descendants, they conclude that a shared blueprint of brain organization has been maintained from the Cambrian until today.

"By comparing known gene expression patterns in living species," Hirth said, "we identified a common signature of all brains and how they are formed."

In Cardiodictyon, three brain domains are each associated with a characteristic pair of head appendages and with one of the three parts of the anterior digestive system.

"We realized that each brain domain and its corresponding features are specified by the same combination genes, irrespective of the species we looked at," added Hirth. "This suggested a common genetic ground plan for making a brain." 

Lessons for vertebrate brain evolution

Hirth and Strausfeld say the principles described in their study probably apply to other creatures outside of arthropods and their immediate relatives. This has important implications when comparing the nervous system of arthropods with those of vertebrates, which show a similar distinct architecture in which the forebrain and midbrain are genetically and developmentally distinct from the spinal cord, they said.

Strausfeld said their findings also offer a message of continuity at a time when the planet is changing dramatically under the influence of climatic shifts.

"At a time when major geological and climatic events were reshaping the planet, simple marine animals such as Cardiodictyon gave rise to the world's most diverse group of organisms – the euarthropods – that eventually spread to every emergent habitat on Earth, but which are now being threatened by our own ephemeral species."

The paper, "The Lower Cambrian Lobopodian Cardiodictyon Resolves the Origin of Euarthropod Brains" was co-authored by Xianguang Hou at the Yunnan Key Laboratory for Paleontology in Yunnan University in Kunming, China, and Marcel Sayre, who has appointments at Lund University in Lund, Sweden, and at the Department of Biological Sciences at Macquarie University in Sydney.

Funding for this work was provided by the National Science Foundation, the University of Arizona Regents Fund, and the UK Biotechnology and Biological Sciences Research Council.

Increased grazing pressure threatens the most arid rangelands


Peer-Reviewed Publication

FACULTY OF SCIENCES OF THE UNIVERSITY OF LISBON

Patagonian steppe (Argentina). 

IMAGE: PATAGONIAN STEPPE (ARGENTINA). view more 

CREDIT: JUAN JOSÉ GAITÁN

A new study published in Science reports results from the first-ever global field assessment of the ecological impacts of grazing in drylands. The international research team found that grazing can have positive effects on ecosystem services, particularly in species-rich rangelands, but these effects turn to negative under a warmer climate.

Grazing is an essential land use that sustains the livelihood of billions of people and is tightly linked to many UN Sustainable Development Goals. Grazing is particularly important in drylands, which cover about 41% of the Earth's land surface, host one in three humans inhabiting our planet and over 50% of all livestock existing in our planet.

Despite the importance of grazing for humans and ecosystems, to date no previous study had attempted to characterize its impacts on the delivery of ecosystem services at the global scale using field data. For doing so, an international research team of more than 100 specialists, led by Dr. Fernando T. Maestre (University of Alicante, Spain), carried out a unique global survey conducted in 326 drylands located in 25 countries from six continents.

“We used standardized protocols to assess the impacts of increasing grazing pressure on the capacity of drylands to deliver nine essential ecosystem services, including soil fertility and erosion, forage/wood production and climate regulation. Doing so allowed us to characterize how the impacts of grazing depend on local climatic, soil and local biodiversity conditions, and to gain additional insights on the role of biodiversity on the provision of ecosystem services essential to sustain human livelihoods”, says Dr. Maestre, director of the Dryland Ecology and Global Change Laboratory (Alicante, Spain).

Researchers found that the relationships between climate, soil conditions, biodiversity and the ecosystem services measured varied with grazing pressure. "The effects of increasing grazing pressure on ecosystem services were mostly negative in warmer drylands. These results highlight the importance of managing grazing locally, to cope with ongoing climate change in drylands, a particularly important issue in oak woodlands (montados) that we studied in Portugal and were part of this work” points Dr. Alice Nunes from the Centre for Ecology, Evolution and Environmental Changes – cE3c, at the Faculty of Sciences of the University of Lisbon (Ciências ULisboa) and coauthor of the study.

The impacts of increasing grazing pressure shifted from mostly positive in colder drylands with a lower rainfall seasonality and higher plant species richness to negative in hotter drylands with lower plant diversity and higher rainfall seasonality. “There is no one-size-fits-all when it comes to grazing in drylands. Any effects of grazing, particularly overgrazing, will vary across the globe, making it important to consider local condition when managing livestock and wild herbivores” says Dr. David Eldridge from the University of New South Wales (Australia) and coauthor of the study.

The authors also found positive relationships between plant species richness and the delivery of multiple ecosystem services such as soil carbon storage, erosion control, and both forage quality and quantity, regardless of grazing pressure. “Our results highlight the importance of conserving and restoring diverse plant communities to prevent land degradation, ensure the delivery of essential ecosystems services for humans, and mitigate climate change in grazed drylands”, says the PhD student Melanie Köbel from cE3c at Ciências ULisboa and coauthor of the study.

The findings of this study are of great relevance for achieving a more sustainable management of grazing, as well as for establishing effective management and restoration actions aimed at mitigating the effects of ongoing climate change and desertification across global drylands.

This work has been carried out as part of the BIODESERT project, awarded by the Consolidator Grant program of the European Research Council (ERC) to Fernando T. Maestre. “I am very grateful to the ERC for supporting this global survey, as such a high risk-high gain project would have not been possible without the generous funding and freedom that comes with an ERC grant. And of course, it would not have been possible without our network of international collaborators, who provided their expertise, resources, and work to survey sites in their respective study areas. The BIODESERT survey also provides a very nice example of the power of global and collaborative research networks to conduct frontier research”, says Dr. Maestre.

Using a standardized survey at 98 sites across six continents, we show that the impacts of increased grazing pressure on the delivery of fundamental ecosystem services depend on climate, soil, and biodiversity across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and species-poor drylands, whereas positive effects of grazing were observed in colder and species-rich areas.

CREDIT

Illustration by Cirenia Arias Baldrich.