New study by researchers from Pusan National University explores the prevalence of heatwaves in East Asia

How do heatwaves develop and how will human-induced climate change affect them?

Peer-Reviewed Publication

PUSAN NATIONAL UNIVERSITY

 

IMAGE: CATEGORIZATION AND CHARACTERIZATION OF HEATWAVES IN DAYS TO COME CAN HELP HUMANITY ADEQUATELY PLAN FOR CATASTROPHIC CLIMATIC CONDITIONS, SUGGESTS A NEW STUDY BY PUSAN NATIONAL UNIVERSITY RESEARCHERS. view more 

CREDIT: PUSAN NATIONAL UNIVERSITY

Described as periods of excessively high temperatures, heatwaves have a devastating impact on human life, agriculture, and water resources. Weather and atmospheric conditions can lead to two types of heatwaves: dry heatwaves occur when the skies are clear, exposing the area to large amounts of solar radiation, while moist heatwaves occur when water vapor traps heat due to cloudy, humid conditions. Owing to the effects of global warming, these events have grown more intense and frequent in recent years. With climate simulations predicting heatwaves to be more frequent and intensify with increasing greenhouse gas emissions, it becomes important to map out vulnerable regions so that adequate plans can be made to deal with them in the future.

Now, in a study published in npj climate and atmospheric science, a team of international researchers led by Professor Kyung-Ja Ha from Pusan National University, South Korea, have analyzed the prevalence of the two types of heatwaves in East Asia. Using historical climate data, they determined for the first time how and where these heatwaves form and also predicted the occurrence of heatwaves in the future under different greenhouse gas emission scenarios.

According to their study, dry heatwaves occur mainly in northwestern East Asia, while moist heatwaves are prevalent over southern East Asia. These heatwaves were observed to have intensified in duration and frequency over the past 60 years (1958–2019).  The research team found that these heatwaves tend to be frequent under favorable large-scale atmospheric conditions, which vary for dry and moist heatwaves. “In dry heatwave regions, anticyclonic, that is clockwise circulation, is amplified after the onset of heatwaves under the influence of the convergence of anomalous wave activity flux over northern East Asia. This results in surface warming via adiabatic processes. In contrast, the moist heatwaves are triggered by the locally generated anticyclonic circulation anomalies, and surface warming in these cases is amplified by cloud and water vapor feedback,” explains Prof. Ha.

The researchers then went on to analyze how increases in greenhouse gas emissions would affect heatwaves. The simulations revealed more frequent dry heatwaves and longer-lasting moist heatwaves even when greenhouse gas emissions were kept to a minimum to limit the temperature rise to 1.5°C, suggesting the need for further reductions in greenhouse gas emissions to avoid severe heatwave conditions.

Studying heatwaves by their types is essential as these events form under different conditions and lead to different outcomes. “Increases in dry heatwaves are expected to damage agriculture, while moist heatwaves can be extremely detrimental to the human body,” cautions Prof. Ha. Identifying vulnerable regions can assist governing bodies in developing strategies that will mitigate the impacts of severe heatwaves. This involves planning for increased electricity use in places at risk of experiencing moist heatwaves and managing water supplies in regions susceptible to dry heatwaves.

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Reference

Authors: Kyung-Ja Ha 1,2, Ye-Won Seo 1,3, Ji-Hye Yeo 1,2, Axel Timmermann 1,3, Eui-Seok Chung 4*, Christian L. E. Franzke 1,3, Johnny C. L. Chan 5, Sang-Wook Yeh 6 and Mingfang Ting 7

DOI: https://doi.org/10.1038/s41612-022-00272-4

Affiliations:     

1 Center for Climate Physics, Institute for Basic Science, Busan, South Korea

2 Department of Atmospheric Sciences, Pusan National University, Busan, South Korea

3 Pusan National University, Busan, South Korea

4 Korea Polar Research Institute, South Korea

5 City University of Hong Kong, China

6 Hanyang University, South Korea

7 Columbia University, USA

 

Lab Page: https://ibsclimate.org , http://gmcl.pusan.ac.kr

ORCID ID (Kyung-Ja Ha): https://orcid.org/0000-0003-1753-9304

 

About Pusan National University

Pusan National University, located in Busan, South Korea, was founded in 1946, and is now the no. 1 national university of South Korea in research and educational competency. The multi-campus university also has other smaller campuses in Yangsan, Miryang, and Ami. The university prides itself on the principles of truth, freedom, and service, and has approximately 30,000 students, 1200 professors, and 750 faculty members. The university is composed of 14 colleges (schools) and one independent division, with 103 departments in all.    

Website: https://www.pusan.ac.kr/eng/Main.do

 

About the authors

Prof. Kyung-Ja Ha, an expert in the climatic extreme and monsoon hydrology at Pusan National University. She joined the department of atmospheric sciences as a faculty member in 1994. Her research group has been leading the research on monsoon dynamics, climate physics, and boundary layer physics. She has also been working at the IBS Center for Climate Physics (ICCP) with Prof. Axel Timmermann (director of ICCP) from 2017 as affiliated professor.

She has coauthored this article with co-corresponding authors, Dr. Ye-Won Seo (ICCP) and Dr. Eui-Seok Chung (KOPRI) who are experts in climate physics and dynamics, developing mechanisms for extremes such as heatwaves, droughts, and compound climatic hazards.

ICCP’s Ji-Hye Yeo, Axel Timmermann, Christian Franzke (ICCP), Johnny Chan (City University of Hong Kong), Sang-Wook Yeh (Hanyang University), and Mingfang Ting (Lamont-Doherty Earth Observatory, Columbia University) are also co-authors of this study.

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JOURNAL

npj Climate and Atmospheric Science

DOI

10.1038/s41612-022-00272-4 

METHOD OF RESEARCH

Computational simulation/modeling

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Dynamics and characteristics of dry and moist heatwaves over East Asia

Do fish suffer from oxygen starvation?

Peer-Reviewed Publication

RADBOUD UNIVERSITY NIJMEGEN

 

IMAGE: BASED ON THEIR INSIGHTS, THE RESEARCHERS HAVE IDENTIFIED – IN GREAT DETAIL AND WORLDWIDE – WHICH FISH ARE LIKELY TO THRIVE IN WHICH BODIES OF WATER, FROM OCEANS TO SMALL RIVERS. "WE CALCULATED THIS FOR TWO 'HYPOTHETICAL' FISHES, ONE LARGE AND ONE SMALL. SMALL FISH DO WELL IN WARM ENVIRONMENTS, SUCH AS THE TROPICS, AND LARGE FISH DO BETTER IN COLDER REGIONS. WE MAY ALSO BE ABLE TO EXTEND THESE PROJECTIONS IN THE FUTURE TO CALCULATE THE EFFECTS OF ENVIRONMENTAL CHANGE." view more 

CREDIT: RADBOUD UNIVERSITY

Larger fishes are more likely to experience oxygen deficiency in warming water than smaller species. The same applies to fish with large cells, note researchers at Radboud University in their latest study. In addition, marine fishes are less tolerant of oxygen-depleted water than freshwater fishes. Based on these insights, the researchers ultimately aim to predict which aquatic species are at risk due to changes in their habitat caused by global warming and human activities. The study will be published in the journal Global Change Biology on 25 July.

Declining dissolved oxygen levels represent a major problem for fish and other aquatic organisms. Oxygen levels decline because the water is heating up due to climate change and because it is becoming more polluted. General biological rules can tell us which fish attributes are beneficial or detrimental when environmental conditions change. "Once we have identified these rules for fish,” says researcher Wilco Verberk, "we can ultimately predict which fish species are most at risk from environmental change."

Large and small cells

There is a lively debate among biologists on the role of oxygen in the sensitivity of fish to water subject to warming. "Many oxygen hypotheses are being fiercely debated. The problem is that the various effects are lumped together. For example, some studies look at how fish respond to oxygen levels in the water but do not account for the temperature of the water or the size of the fish. As a result, the reported patterns are variable," Verberk explains.

Verberk and colleagues have systematically separated the various effects and compiled data on tolerance to deficiency oxygen from 195 fishes to resolve this discussion. When analysing the data, they saw that larger fishes are more sensitive to oxygen stress, but only in warm water. When the water is cold, the effect is reversed.

The researchers saw a similar effect for fish that have relatively large cells. "Many people think that all animal species have the same cell size, but some animals have large cells, and some have small cells, even within the same species. There are many advantages to having small cells, especially in warm water. For example, small cells have relatively more membrane area, which is needed to absorb oxygen from their surrounding environment.”

Fresh water and saltwater

In addition, the researchers found differences between freshwater fish and marine fish. "Far too often, scientific studies only compare marine and terrestrial life. Indeed, freshwater species are sometimes lumped with terrestrial species. It is a missed opportunity because taking these differences into account can greatly increase our understanding of the environmental impacts of climate change."

According to the study by Verberk and colleagues, freshwater fishes appear to be more tolerant of oxygen-depleted water than marine fishes. "The explanation probably involves different selection pressures on freshwater fish during their evolutionary history. In the ocean, the temperature is relatively stable, but in fresh water the fish are more often confronted with higher temperatures. Fluctuations in oxygen levels are also larger in rivers and especially in lakes, for example, due to the presence of algae."

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JOURNAL

Global Change Biology

DOI

10.1111/GCB.16319 

ARTICLE TITLE

Body mass and cell size shape the tolerance of fishes to low oxygen in a temperature-dependent manner

ARTICLE PUBLICATION DATE

25-Jul-2022

Disclaimer: AAAS

Effects of lead poisoning may be reversible with early-childhood enrichment

New research shows that the majority of gene changes in the brain caused by lead can be reversed by raising animals in stimulating environments.

Peer-Reviewed Publication

THOMAS JEFFERSON UNIVERSITY

PHILADELPHIA -- Lead exposure in early childhood can lead to severe cognitive and behavioral impairments in children that last well into adolescence and adulthood. Although researchers have looked at effects of early life lead exposure on a small number of genes involved in learning, memory, and brain development, research was lacking as to the full extent of the toxicity.  New research from Thomas Jefferson University shows that over 3,500 genes in the hippocampus, a part of the brain involved in learning and memory are affected by lead poisoning. The work also shows that providing animals with stimulating environments early in life can reverse the large majority of these genetic changes, reinforcing the potentially important role of early-childhood education in combating the effects of lead poisoning.

“Children who live in housing stock built before 1978, the year in which lead was banned as an ingredient in paint, are at high risk of being exposed to lead from lead dust or chipping and peeling lead-containing paint in their homes,” says senior author Jay Schneider, PhD, professor of Pathology, Anatomy and Cell Biology at Thomas Jefferson University. “Recent estimates suggest that there are at least a half million children in the U.S. with blood lead levels at or above amounts that can adversely affect cognitive function. Our work demonstrates that by providing an enriched early life environment, the adverse effects of lead on the brain may be minimized or potentially reversed, emphasizing how important early childhood interventions may be.”

Together with lead author Garima Singh, PhD, a research assistant professor in the department of Pathology, Anatomy and Cell Biology and colleagues, the authors looked at rats that were exposed to lead from birth to the time of weaning, at 21 days of age. “Our experiments aimed to replicate conditions of human lead exposure,” says Dr. Singh. “21 days of age for rats is the equivalent to an age of about 2-3 years in humans, which is commonly when lead exposure occurs. That is because crawlers and toddlers are likely to put many things in their mouths including paint chips or toys covered in dust from deteriorating lead paint.”

From 21 days, the lead-exposed animals were separated into two different housing conditions:  ones that were either enriched or ones that lacked stimulation. The so-called enriched cages had more social activity, with a total of 6 rats, together with chew toys and various things to climb on and burrow through that were changed twice every week for novelty. The non-enriched cages were smaller, only held 3 animals and did not contain any additional stimulation. “We now know that stimulating social environments are as important for rodents as they are for human children, in terms of cognitive and behavioral health and with effects on physical health as well,” says Dr. Singh.

The researchers looked at changes in expression of genes from the part of the brain involved in memory – the hippocampal region. They found that the expression levels of over 3,500 genes were affected by the lead exposure, either abnormally churning out more or less of their gene products.  “These data show for the first time that at a genome-wide level, a large number of hippocampal genes involved in various biological processes and functions are affected by lead exposure and further modified by an enriched environment,” says Dr. Schneider. In rats exposed to lead, the genes affected were amongst those involved in memory and nerve signaling pathways, and also those involved in brain development.

However, approximately 80% of the gene expression changes induced by the lead exposure were reversed in the group of animals that lived in the stimulating environment until day 55, which is roughly equivalent to adolescence in humans. Additionally, the animals living in the non-enriched environment had memory deficits while the animals living in the enriched environment did not.

“We know that there is no safe level of lead exposure for children,” says Dr. Schneider. “Lead can damage the brain and derail normal brain development. However, our work suggests that it may be possible to mitigate the wide-spread adverse effects of lead on the young brain by providing adequate access to stimulating, interesting environments and activities in early childhood and perhaps longer. Unfortunately, these kinds of resources are often not available to the population most at risk for lead poisoning, that is, children who are growing up in impoverished or low socioeconomic environments.”  Drs. Schneider and Singh agree that although more research needs to be done in this area, the importance of early intervention programs with environmental enrichment cannot be overstated.

This research was supported by NIH grant R01ES030742. Bioinformatics support was provided in part from the Center of Excellence in Environmental Toxicology (CEET), University of Pennsylvania, Center Grant. The authors report no competing interests.

Article reference: G. Singh, V. Singh, T. Kim, A. Ertel, W. Fu and J.S. Schneider, “Altered Genome-Wide Hippocampal Gene Expression Profiles Following Early Life Lead Exposure and their Potential for Reversal by Environmental Enrichment,” Scientific Reports, 2022.

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JOURNAL

Scientific Reports

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Altered Genome-Wide Hippocampal Gene Expression Profiles Following Early Life Lead Exposure and their Potential for Reversal by Environmental Enrichment

ARTICLE PUBLICATION DATE

25-Jul-2022

Bacterial community signatures reveal how cities urbanize water sources

Peer-Reviewed Publication

LEIBNIZ INSTITUTE FOR ZOO AND WILDLIFE RESEARCH (IZW)

 

IMAGE: STECHLINSEE view more 

CREDIT: SOLVIN ZANKL/IGB

Bacterial communities are often well adapted and stable in a particular environment whether it be a human mouth or a lake. Humans are altering environments at an increasing rate, none more so than in cities and their surroundings in the process of urbanization. In a study published today in the journal “Science of the Total Environment“, led by scientists from the Leibniz Institute for Freshwater Ecology and Inland Fisheries (IGB) and the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) as part of the Leibniz Research Alliance “Infections”, bacterial communities were examined in urban water bodies and wastewater in Berlin and compared to less anthropogenically influenced lakes from surrounding rural regions. The results reveal that urbanization introduces large amounts of nutrients, chemical pollutants and antimicrobial products, and thereby changes the makeup of the microbiome by favouring groups of bacteria that contain human pathogenic bacteria, with yet unknown consequences for ecosystem functioning and human and animal health.

Whether an armpit, garden soil or water, almost every place on earth has its own natural bacterial community. By altering environments, humans also change the bacterial composition of such places by creating new conditions that favour some groups of bacteria over others. In a new study, scientists from IGB and Leibniz-IZW along with colleagues from other members of the Leibniz Research Alliance tracked these changes in bacterial composition connected with the process of urbanization and demonstrated that bacterial communities in urban waterbodies and wastewater in Berlin are distinctly different from those of rural lakes in surrounding regions in the federal states of Brandenburg and Mecklenburg-Vorpommern. The process of urbanization does not only introduce human bacteria (“humanisation”) but can also introduce excessive amounts of nutrients (“eutrophication”), chemical pollutants and antimicrobial products such as antibiotics, which can drastically favour specific bacteria over others and change the makeup of the microbiome with yet unknown consequences for ecosystem functioning and human and animal health. 

“We wanted to know whether urban water shows signatures of urbanization that are predictive of the types of bacteria present in a given community within the city limits,” says Prof Hans Peter Grossart of the IGB, co-principle investigator of the study. The results demonstrate that multiple bacterial groups are enriched in urban waters, the most extreme examples being found in the inflows and outflows of a wastewater treatment plant, pointing to a “humanisation” of urban lake microbiomes.

“Surprisingly, the enriched bacterial groups in urban environments are those that often contain pathogenic species. This suggests that if a pathogen gets into such an environment, it will find a very supportive environment in which to grow,” says Prof Alex Greenwood, head of the Leibniz-IZW Department of Wildlife Diseases and co-principle investigator of the study. This could potentially lead to outbreaks in such environments compared to rural water bodies, where such favourable conditions for pathogens were not found in general. 

In the future, water hygiene may have to consider de-urbanizing the microbiomes of city water sources to establish more natural water ecosystems within the city. This will become increasingly challenging and important as climate change makes many urban areas dryer and more nutrient rich, further altering the bacterial communities of urbanized water. This may have profound effects for human and animal health as the risk of contamination with harmful microbes increases.

Press Contact

Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) in the Forschungsverbund Berlin e.V.
Müggelseedamm 310, 12587 Berlin, Germany

Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) in the Forschungsverbund Berlin e.V.
Alfred-Kowalke-Straße 17, 10315 Berlin, Germany

JOURNAL

Science of The Total Environment

DOI

10.1016/j.scitotenv.2022.157321 

METHOD OF RESEARCH

Meta-analysis

ARTICLE TITLE

Urbanization promotes specific bacteria in freshwater microbiomes including potential pathogens.

ARTICLE PUBLICATION DATE

15-Jul-2022

Floors in ancient Greek luxury villa were laid with recycled glass

Peer-Reviewed Publication

UNIVERSITY OF SOUTHERN DENMARK

 

IMAGE: EXCAVATION AND MOSAIC FLOORS OF VILLA. view more 

CREDIT: UNIVERSITY OF SOUTHERN DENMARK

Although this 1700 years old luxury villa was excavated and examined both in 1856 and in the 1990s, it still has secrets to reveal.

New secrets have now been revealed by an international research team, with Professor and expert in archaeometry, Kaare Lund Rasmussen from University of Southern Denmark leading the so called archaeometric analyses: using chemical analysis to determine which elements an object was made of, how it has been processed, etc.

Others in the team are Thomas Delbey from Cranfield University in England and the classical archaeologists Birte Poulsen and Poul Pedersen from Aarhus University and University of Southern Denmark. The team’s work is published in the journal Heritage Science, including archaeometric analysis of 19, approximately, 1600 years old mosaic tesserae.

One of seven wonders of the world

The tesserae originate from an excavation of a villa from late antiquity, located in Halikarnassos (today Bodrum in Anatolia, Turkey). Halikarnassos was famous for King Mausolus' giant and lavish tomb, which was considered one of the seven wonders of the world.

The villa was laid out around two courtyards and the many rooms were adorned with mosaic floors. In addition to geometric patterns, there were also motifs of various mythological figures and scenes taken from Greek mythology; e.g. Princess Europa being abducted by the god Zeus in the form of a bull and Aphrodite at sea in her seashell.

Motifs from the stories of the much younger Roman author Virgil are also represented.

Inscriptions in the floor have revealed that the owner was named Charidemos and that the villa was built in the mid-fifth century.

CAPTION

selection of the mosaic tesserae, investigated by professor Kaare Lund Rasmussen/ University of Southern Denmark.

CREDIT

Kaare Lund Rasmussen/University of Southern Denmark

A costly luxury

Mosaic flooring was a costly luxury: expensive raw materials like white, green, black, and other colors of marble had to be transported from distant quarries. Other stone materials, ceramics and glasses also had to be imported.

- I received 19 mosaic tesserae for analysis in my lab in Denmark. Of these, seven were of glass in different colors; purple, yellow, red, and deep red. My conclusion is that six of them are probably made of recycled glass, says Kaare Lund Rasmussen.

This conclusion is based on a chemical analysis called inductively coupled plasma mass spectrometry. With it, the research team has determined the concentrations of no less than 27 elements, some of them all the way down to a concentration of billionths of a gram.

Waning of Roman Empire

- We were able to distinguish between base glass from Egypt and base glass from the Middle East and also, we could determine which elements were added by the ancient craftsmen to color the glasses and to make them opaque, which was preferred at the time, he says.

It is of course difficult to extrapolate from only seven glass mosaic tesserae, but the new results fit very well with the picture of Anatolia in late antiquity. As the power of the Roman Empire waned, trade routes were closed or rerouted, which probably led to a shortage of goods in many places - including raw materials for glass production in Anatolia.

This, together with the stories depicted on the floors, allows the classical archaeologists to put together a more detailed picture of what was fashionable in late antiquity and what the possibilities were for the artistic unfolding.

CAPTION

Detail of mosaic floor

CREDIT

Kaare Lund Rasmussen/University of Southern Denmark.

JOURNAL

Heritage Science

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Materials and technology of mosaics from the House of Charidemos at Halikarnassos (Bodrum, Turkey)

Study: Explosive volcanic eruption produced rare mineral on Mars

Researchers publish scenario that explains 2016 discovery by NASA’s Curiosity rover

Peer-Reviewed Publication

RICE UNIVERSITY

 

IMAGE: KIRSTEN SIEBACH IS AN ASSISTANT PROFESSOR IN RICE’S DEPARTMENT OF EARTH, ENVIRONMENTAL AND PLANETARY SCIENCES AND A MISSION SPECIALIST ON NASA’S CURIOSITY MARS ROVER TEAM. view more 

CREDIT: PHOTO BY TOMMY LAVERGNE/RICE UNIVERSITY

HOUSTON – (July 25, 2022) – Planetary scientists from Rice University, NASA’s Johnson Space Center and the California Institute of Technology have an answer to a mystery that’s puzzled the Mars research community since NASA’s Curiosity rover discovered a mineral called tridymite in Gale Crater in 2016.

Tridymite is a high-temperature, low-pressure form of quartz that is extremely rare on Earth, and it wasn’t immediately clear how a concentrated chunk of it ended up in the crater. Gale Crater was chosen as Curiosity’s landing site due to the likelihood that it once held liquid water, and Curiosity found evidence that confirmed Gale Crater was a lake as recently as 1 billion years ago.

“The discovery of tridymite in a mudstone in Gale Crater is one of the most surprising observations that the Curiosity rover has made in 10 years of exploring Mars,” said Rice’s Kirsten Siebach, co-author of a study published online in Earth and Planetary Science Letters. “Tridymite is usually associated with quartz-forming, explosive, evolved volcanic systems on Earth, but we found it in the bottom of an ancient lake on Mars, where most of the volcanoes are very primitive.”

Siebach, an assistant professor in Rice’s Department of Earth, Environmental and Planetary Sciences, is a mission specialist on NASA’s Curiosity team. To suss out the answer to the mystery, she partnered with two postdoctoral researchers in her Rice research group, Valerie Payré and Michael Thorpe, NASA’s Elizabeth Rampe and Caltech’s Paula Antoshechkina. Payré, the study’s lead author, is now at Northern Arizona University and preparing to join the faculty of the University of Iowa in the fall.

Siebach and colleagues began by reevaluating data from every reported find of tridymite on Earth. They also reviewed volcanic materials from models of Mars volcanism and reexamined sedimentary evidence from the Gale Crater lake. They then came up with a new scenario that matched all the evidence: Martian magma sat for longer than usual in a chamber below a volcano, undergoing a process of partial cooling called fractional crystallization that concentrated silicon. In a massive eruption, the volcano spewed ash containing the extra silicon in the form of tridymite into the Gale Crater lake and surrounding rivers. Water helped break down the ash through natural processes of chemical weathering, and water also helped sort the minerals produced by weathering.

The scenario would have concentrated tridymite, producing minerals consistent with the 2016 find. It would also explain other geochemical evidence Curiosity found in the sample, including opaline silicates and reduced concentrations of aluminum oxide.

“It's actually a straightforward evolution of other volcanic rocks we found in the crater,” Siebach said. “We argue that because we only saw this mineral once, and it was highly concentrated in a single layer, the volcano probably erupted at the same time the lake was there. Although the specific sample we analyzed was not exclusively volcanic ash, it was ash that had been weathered and sorted by water.”

If a volcanic eruption like the one in the scenario did occur when Gale Crater contained a lake, it would mean explosive volcanism occurred more than 3 billion years ago, while Mars was transitioning from a wetter and perhaps warmer world to the dry and barren planet it is today.

“There’s ample evidence of basaltic volcanic eruptions on Mars, but this is a more evolved chemistry,” she said. “This work suggests that Mars may have a more complex and intriguing volcanic history than we would have imagined before Curiosity.”

The Curiosity rover is still active, and NASA is preparing to celebrate the 10th anniversary of its landing next month.

The research was funded by NASA (15-MSLPSP15_2-0051, 15-MSLPSP15_0015, 80NSSC22K0732), the National Science Foundation (1947616) and Rice’s Department of Earth, Environmental and Planetary Sciences.

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Peer-reviewed paper:

“Tridymite in a lacustrine mudstone in Gale Crater, Mars: Evidence for an explosive silicic eruption during the Hesperian” | Earth and Planetary Science Letters | DOI: 10.1016/j.epsl.2022.117694

Authors: Valerie Payré, Kirsten Siebach, Michael Thorpe, Paula Antoshechkina and Elizabeth Rampe

https://doi.org/10.1016/j.epsl.2022.117694

Image downloads:

https://mars.nasa.gov/resources/7438/looking-up-at-mars-rover-curiosity-in-buckskin-selfie/
CAPTION: NASA's Curiosity Mars rover snapped this low-angle self-portrait at the site where it drilled into a rock July 30, 2015, producing a powder (visible in foreground) that was later confirmed to contain the rare mineral tridymite. (Image courtesy of NASA/JPL-Caltech/MSSS)

https://mars.nasa.gov/resources/7604/buckskin-drill-hole-and-chemin-x-ray-diffraction/
CAPTION: NASA's Curiosity Mars Rover drilled this hole to collect sample material from a rock target called "Buckskin" on July 30, 2015. The diameter of the hole is slightly smaller than a U.S. dime. Rock powder from the drill site was subsequently delivered to a laboratory inside the rover and found to contain the rare mineral tridymite. (Image courtesy of NASA/JPL-Caltech/MSSS)

https://news-network.rice.edu/news/files/2022/07/0725_MARS-ks-lg.jpg
CAPTION: Kirsten Siebach (Photo courtesy of Rice University)

Related stories:

Mars, happy to see you again – Feb. 22, 2021
https://news.rice.edu/news/2021/mars-happy-see-you-again

Rice scientist joins next Mars adventure – Dec. 2, 2020
https://news.rice.edu/news/2020/rice-scientist-joins-next-mars-adventure

Links:

Siebach Lab: kirstensiebach.com/lab

Department of Earth, Environmental and Planetary Sciences: earthscience.rice.edu

Wiess School of Natural Sciences: naturalsciences.rice.edu

This release can be found online at news.rice.edu.

Follow Rice News and Media Relations via Twitter @RiceUNews.

Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation’s top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 4,240 undergraduates and 3,972 graduate students, Rice’s undergraduate student-to-faculty ratio is just under 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for lots of race/class interaction and No. 1 for quality of life by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger’s Personal Finance.

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JOURNAL

Earth and Planetary Science Letters

DOI

10.1016/j.epsl.2022.117694 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Tridymite in a lacustrine mudstone in Gale Crater, Mars: Evidence for an explosive silicic eruption during the Hesperian

New methodology helps predict soil recovery after wildfires

Peer-Reviewed Publication

AMERICAN SOCIETY FOR MICROBIOLOGY

Washington, D.C. - Soils influence water quality, and they are critical to plant growth. However, it has been difficult to predict how plant growth and water quality would change in the wake of wildfires. Now, a team of Colorado investigators has devised new methodology to enable such predictions. The research is published in Applied and Environmental Microbiology, a journal of the American Society for Microbiology.

“To make practical predictions about recovery, we had to use a modern artificial intelligence tool called statistical learning,” said John Spear, Ph.D., professor, Civil and Environmental Engineering, Colorado School of Mines, Golden, Colo. “When we fed data about the microbes and nutrients into this model, we were able to predict how soil is changed by fire far more accurately.”

Spear emphasized that combining information on the types and quantities of both microbes and nutrients increased accuracy. Another intriguing discovery was that including microbiota that are uncommon in soil—those that constituted less than 1% of the microbiome—was critical to the predictions’ accuracy.

“This apparent contradiction is a fascinating outcome of our study and runs contrary to the common wisdom that if we measure 99% of what’s living in soil, we’ll have a great sense of how that soil will behave,” said first author Alexander S. Honeyman, Ph.D., research associate at the Colorado School of Mines.

The investigators were also able to predict water quality by analyzing the microbiome for species that affect both soil regeneration and downstream waters, said Spear, who added that the methodology may lead to a better understanding of both terrestrial and aquatic ecosystem recovery post-wildfire.

In the study, “We went out to 2 active wildfires in Colorado in 2018 and 2019, and collected soil shortly after the smoldering stopped,” said Spear. “This was as simple as shoveling soil into a bucket. We returned to the same sites for 3 summers [2018, 2019, and 2020], collecting more samples, and followed up as the landscape recovered from the black of burn to the green of new growth.”

Back in the lab, the investigators measured soil carbon, nitrogen and other important molecules. They also took the census of the microbiome—the species present, and the quantities of each in the soils.

“The trick,” said Spear, “was to do this over and over in a thorough fashion for 3 years, generating a dataset of more than 500 soil samples. Then, we wanted to see if the pattern of recovery of soil after fire could be predicted from this unique dataset, using statistical learning.”

The methodology worked, despite the fact that the dataset is quite diverse—representing different severities of wildfire and various soil types and seasons. “That’s good news for our approach, because [the methodology] appears to work on many different conditions of soil,”  said Spear.

The research was motivated by Honeyman’s decade of experience as a volunteer firefighter, and having lost his home to a Colorado wildfire in 2010. This experience raised important questions for him. Would soil recover nutrients that had been lost in a fire? The investigators also wanted to know whether water quality would be renewed. "We asked ourselves how we could describe recovery in a way that’s actually useful to land managers,” said Spear, noting that, “our forest service coauthors, who are land managers, really liked this work.”

As climate change contributes to more frequent fires, it is critical that we understand how to manage the recovery of burned soil, particularly in the western U.S., said Spear.

Spear noted that the methodology could likely also be applied to agriculture to boost food production “even while using less water and less fertilizer, thus saving money.”
 

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JOURNAL

Applied and Environmental Microbiology

DOI

10.1128/aem.00343-22 

ARTICLE TITLE

Statistical Learning and Uncommon Soil Microbiota Explain Biogeochemical Responses after Wildfire