Biodiversity in the city: Designing urban spaces for humans and animals

Technical University of Munich (TUM)

Animals and plants also live and thrive on public squares. This creates opportunities for greater biodiversity and well-being for the human population. Researchers at the Technical University of Munich (TUM) have studied at 103 locations in Munich how various factors affect flora and fauna. They advocate a close examination of local conditions and a more nature-focussed approach to the design of public spaces.

Biodiversity is the foundation of functional ecosystems: diverse ecosystems are more stable and have greater resiliency to the effects of climate change. However, humans also benefit directly from having a wide range of plant and animal life in their surroundings. A growing number of studies have demonstrated the positive effects on the human immune system, moods and the microbiome, as the microorganism population of the body is known. “Especially with rising urbanization, it makes sense to take a closer look at the coexistence of humans and animals in the city,” says Wolfgang Weisser, Professor of Terrestrial Ecology at TUM.

Together with Andrew J. Fairbairn and Sebastian T. Meyer, the first authors of the study, and students and staff of the chair, Wolfgang Weisser studied biodiversity at 103 public squares in Munich. The team looked at such factors as size, the occurrence of lawn, plant and tree growth, artificial light sources and green in the surroundings of the location within a 1,000 meter radius. The squares varied from almost entirely sealed to park-like squares.

Their results show, with Munich as an example, how greatly the different spaces can differ in the animals and other organisms that can live there. At the heavily sealed Marienplatz, the researchers counted only 20 species, with just one bird and moss species as well as insects and bat species. Meanwhile, at Pfrontener Platz, a space with lawns, bushes and trees, they found 156 taxa, including 21 different kinds of birds. At Johannisplatz, 118 species are present, as it has trees, hedges and some grassy areas despite being sealed to a relatively large extent.

More detailed planning needed for plantings

Unsurprisingly, more plants are beneficial to many animal species. This is a factor that urban planning models already take into account. However, the study also shows that lawns, trees and bushes vary widely in terms of the diversity and numbers of the species they attract. So far, public spaces are designed with humans in mind, with little consideration to animals and other species.

Almost all of the species investigated benefit from lawns as they are home to soil organisms that also serve as a food source, for hedgehogs and birds, for example. Trees and bushes also have positive effects, especially when combined with grassy vegetation. At the same time the team was able to show that some species also seek the heat of the city center, while others prefer the cooler outlying areas, where there is also less light pollution.

Consciously planning for the coexistence of humans and animals

Based on those insights, the researchers concluded that the chances for greater biodiversity are increased if, instead of applying the same patterns to every location, planners take into account the local conditions and the needs of different species. To encourage more bee species, for example, they should not only plant nectar-bearing flowers, but also provide open space as habitat for the bees and a source of nest-building material – even  close to the city center because pollinators like warm conditions.

“We understand that spaces fulfil various functions and that not every area is suitable for large-scale restructuring,” says Wolfgang Weisser. “But with just a few measures one can already achieve a lot and allow for positive people-nature-relationships. If we incorporate factors with a positive influence on biodiversity in urban planning, we can utilize the available potential to do good not only for nature but also for ourselves.”

Publication:
Fairbairn, A.J., Meyer, S.T., Mühlbauer, M. et al.: Urban biodiversity is affected by human-designed features of public squares. Nat Cities 1 (2024). DOI: 10.1038/s44284-024-00126-5

Further recent publications on the coexistence of humans and animals:

• Weisser, W. W., Hauck, T. E.: Animal-Aided Design – planning for biodiversity in the built environment by embedding a species’ life-cycle into landscape architectural and urban design processes. Landscape Research (2024). DOI: 10.1080/01426397.2024.2383482
• Visintin, C., Garrard, G. E., Weisser, W. W. et al.: Designing cities for everyday nature. Conservation Biology, (2024). DOI: 10.1111/cobi.14328

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Journal

Nature Cities

DOI

10.1038/s44284-024-00126-5 

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Colorado.eduspot.colorado.edu/~norcross/Wh1.pdf

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Method of Research

Observational study

Subject of Research

Animals

Article Title

Urban biodiversity is affected by human-designed features of public squares

 

NASA satellites reveal abrupt drop in global freshwater levels

The Earth’s total amount of freshwater dropped abruptly starting in May 2014 and has remained low ever since. The shift could indicate Earth's continents have entered a persistently drier phase.

NASA/Goddard Space Flight Center

 

image: 

This map shows the years that terrestrial water storage hit a 22-year minimum (i.e., the land was driest) at each location, based on data from the GRACE and GRACE/FO satellites. A significantly large portion of the global land surface reached this minimum in the nine years since 2015, which happen to be the nine warmest years in the modern temperature record.

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Credit: Image by NASA Earth Observatory/Wanmei Liang with data courtesy of Mary Michael O’Neill

An international team of scientists using observations from NASA-German satellites found evidence that Earth’s total amount of freshwater dropped abruptly starting in May 2014 and has remained low ever since. Reporting in Surveys in Geophysics, the researchers suggested the shift could indicate Earth's continents have entered a persistently drier phase.

From 2015 through 2023, satellite measurements showed that the average amount of freshwater stored on land — that includes liquid surface water like lakes and rivers, plus water in aquifers underground — was 290 cubic miles (1,200 cubic km) lower than the average levels from 2002 through 2014, said Matthew Rodell, one of the study authors and a hydrologist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “That’s two and a half times the volume of Lake Erie lost.”

During times of drought, along with the modern expansion of irrigated agriculture, farms and cities must rely more heavily on groundwater, which can lead to a cycle of declining underground water supplies: freshwater supplies become depleted, rain and snow fail to replenish them, and more groundwater is pumped. The reduction in available water puts a strain on farmers and communities, potentially leading to famine, conflicts, poverty, and an increased risk of disease when people turn to contaminated water sources, according to a UN report on water stress published in 2024.

The team of researchers identified this abrupt, global decrease in freshwater using observations from the Gravity Recovery and Climate Experiment (GRACE) satellites, operated by the German Aerospace Center, German Research Centre for Geosciences, and NASA. GRACE satellites measure fluctuations in Earth’s gravity on monthly scales that reveal changes in the mass of water on and under the ground. The original GRACE satellites flew from March 2002 to October 2017. The successor GRACE–Follow On (GRACE–FO) satellites  launched in May 2018.

The decline in global freshwater reported in the study began with a massive drought in northern and central Brazil, and was followed shortly by a series of major droughts in Australasia, South America, North America, Europe, and Africa. Warmer ocean temperatures in the tropical Pacific from late 2014 into 2016, culminating in one of the most significant El Niño events since 1950, led to shifts in atmospheric jet streams that altered weather and rainfall patterns around the world. However, even after El Niño subsided, global freshwater failed to rebound.  In fact, Rodell and team report that 13 of the world’s 30 most intense droughts observed by GRACE occurred since January 2015. Rodell and colleagues suspect that global warming might be contributing to the enduring freshwater depletion.

Global warming leads the atmosphere to hold more water vapor, which results in more extreme precipitation, said NASA Goddard meteorologist Michael Bosilovich. While total annual rain and snowfall levels may not change dramatically, long periods between intense precipitation events allow the soil to dry and become more compact. That decreases the amount of water the ground can absorb when it does rain. 

“The problem when you have extreme precipitation,” Bosilovich said, “is the water ends up running off,” instead of soaking in and replenishing groundwater stores. Globally, freshwater levels have stayed consistently low since the 2014-2016 El Niño, while more water remains trapped in the atmosphere as water vapor. “Warming temperatures increase both the evaporation of water from the surface to the atmosphere, and the water-holding capacity of the atmosphere, increasing the frequency and intensity of drought conditions,” he noted.

While there are reasons to suspect that the abrupt drop in freshwater is largely due to global warming, it can be difficult to definitively link the two, said Susanna Werth, a hydrologist and remote sensing scientist at Virginia Tech, who was not affiliated with the study. “There are uncertainties in climate predictions,” Werth said. “Measurements and models always come with errors.”

It remains to be seen whether global freshwater will rebound to pre-2015 values, hold steady, or resume its decline. Considering that the nine warmest years in the modern temperature record coincided with the abrupt freshwater decline, Rodell said, “We don’t think this is a coincidence, and it could be a harbinger of what’s to come.”

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Journal

Surveys in Geophysics

DOI

10.1007/s10712-024-09860-w 

Article Title

An Abrupt Decline in Global Terrestrial Water Storage and Its Relationship with Sea Level Change

 

Novel magnetic field integration enhances green hydrogen peroxide production

Advanced Institute for Materials Research (AIMR), Tohoku University

 

image: 

Title image

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Credit: ©Hao Li et al.

Researchers have achieved a breakthrough in improving the efficiency of an electrochemical reaction that produces hydrogen peroxide - a vital chemical for industrial applications such as disinfection, bleaching, and sewage treatment. This reaction, called the oxygen reduction reaction (ORR), was improved by developing a new class of heterogeneous molecular catalysts with an integrated magnetic field.

The conventional methods of producing hydrogen peroxide (H2O2) have unfortunate downsides. The process is energy-intensive, and the concentrated end product is difficult to transport safely. To face this issue, the research team looked towards an electrochemical method that is not only more efficient, but also environmentally friendly.

The research team designed a novel catalyst by anchoring cobalt phthalocyanine (CoPc) molecules on carbon black (CB), then integrating it with polymer-protected magnetic (Mag) nanoparticles. This unique structure enables effective spin state manipulation of the cobalt active sites, significantly enhancing catalytic performance.

The researchers discovered the CoPc/CB-Mag catalyst achieved a remarkable H2O2 production efficiency of 90% and significantly enhanced the reaction's efficiency. Notably, the catalyst requires only minimal amounts of magnetic materials - up to seven orders of magnitude less than previous approaches - making it both safer and more practical for large-scale applications.

"Our integrated magnetic field approach can shift the cobalt center from low-spin to high-spin state without modifying its atomic structure," said Di Zhang of the Advanced Institute for Materials Research (WPI-AIMR), "This spin transition dramatically improves the catalyst's intrinsic activities in both oxygen reduction and evolution reactions."

To understand the fundamental mechanism behind this new catalyst, they used a technique called comprehensive density functional theory (DFT) calculations. Understanding why and how it works is important for future studies. "We found that the high-spin Co site exhibits stronger binding with oxygen-containing intermediates, which is crucial for efficient catalysis," explained Associate Professor Hao Li, "The magnetic field-induced spin polarization also facilitates electron transfer and spin transitions during the reaction steps, boosting the catalytic kinetics."

"The combination of experimental results and theoretical insights provides a comprehensive picture of how magnetic fields can enhance catalytic performance," added Li, "This can serve as guidance when designing new catalysts in the future."

The findings could lead to the rational design of catalytic active materials, targeting for more efficient and environmentally friendly pathways to produce hydrogen peroxide and other value-added chemicals, contributing to global efforts in sustainable industrial processes and carbon-neutral energy technologies.

Integration of magnetic nanoparticles with molecular catalysts: Schematic illustration showing the CoPc/CB-Mag catalyst with polymer-protected magnetic nanoparticles, enabling spin state manipulation of cobalt centers. 

Catalytic performance enhancement: Comparative results showing improved hydrogen peroxide production efficiency and oxygen evolution reaction performance with the magnetic field-integrated catalyst.

CREdit

©Hao Li et al.

About the World Premier International Research Center Initiative (WPI)

The WPI program was launched in 2007 by Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT) to foster globally visible research centers boasting the highest standards and outstanding research environments. Numbering more than a dozen and operating at institutions throughout the country, these centers are given a high degree of autonomy, allowing them to engage in innovative modes of management and research. The program is administered by the Japan Society for the Promotion of Science (JSPS).

See the latest research news from the centers at the WPI News Portal: https://www.eurekalert.org/newsportal/WPI
Main WPI program site:  www.jsps.go.jp/english/e-toplevel

 

Advanced Institute for Materials Research (AIMR)
Tohoku University
Establishing a World-Leading Research Center for Materials Science

AIMR aims to contribute to society through its actions as a world-leading research center for materials science and push the boundaries of research frontiers. To this end, the institute gathers excellent researchers in the fields of physics, chemistry, materials science, engineering, and mathematics and provides a world-class research environment.

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Journal

Advanced Materials

DOI

10.1002/adma.202408461 

Article Title

Spin Manipulation of Heterogeneous Molecular Electrocatalysts by an Integrated Magnetic Field for Efficient Oxygen Redox Reactions

 SPACE/COSMOS

Chang’e-6 lunar samples reveal 2.83-billion-year-old basalt with depleted mantle source

Chinese Academy of Sciences Headquarters

 

image: 

Fig. 1 Landing site of the Chang’e-6 mission on the Moon’s far side

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Credit: Image by GIGCAS

The Moon has a global dichotomy, with its near and far sides having different geomorphology, topography, chemical composition, crustal thickness, and evidence of volcanism.
To better understand this dichotomy, Professor XU Yigang’s team from the Guangzhou Institute of Geochemistry of the Chinese Academy of Sciences investigated lunar soil samples from the far side South Pole-Aitken (SPA) Basin of the Moon returned by the Chang’e-6 mission.
Their work was published in Science on Nov. 15.
“The samples returned by Chang’e-6 provide a best opportunity to investigate the lunar global dichotomy,” said Professor XU.
Volcanic eruptions flooded parts of the surface with lava, producing rocks known as mare basalts, which are more common on the near side, where they cover ~30% of the surface compared to 2% of the far side. It is obvious that to investigate the lunar global dichotomy, samples from both the near and far sides are needed.
The Chang’e-6 lunar soils contain two types of mare basalts: low-Ti and very low-Ti (VLT). The predominant low-Ti basalt represents the local basalt unit around the landing site, whereas the VLT basalt possibly came from the unit to the east of the landing site (Figure 1B).
The high-precision Pb-Pb dating of Zr-bearing minerals and Rb-Sr dating of plagioclase and late-stage mesostasis of the low-Ti basalt yield consistent isochron ages of 2.83 Ga (Figure 2), indicating that “young magmatism also exits on the lunar far side,” according to the study.
Compared to the near side samples returned by the Apollo and Chang’e-5 missions, the Chang’e-6 low-Ti basalt has a low μ value and 87Sr/86Sr and a very high εNd value (Figure 3), suggesting a very depleted mantle source.
Crustal thickness has been suggested as a key factor in accounting for asymmetry in the abundance of volcanism between the lunar near side and far side. However, this model has been questioned since the SPA basin on the far side, which has an anomalously thin crust, appears deep and significantly underfilled by volcanism.
Based on the investigation of Chang’e-6 low-Ti basalt, XU’s team suggested that the composition of the mantle source is another important factor controlling the generation of lunar volcanic activity.
“Although the SPA basin has a thin crust, the depleted and refractory mantle source beneath the SPA basin hinders partial melting to a large degree,” said XU.
This work also provides an additional calibration point at 2.83 Ga for the lunar crater chronology and implies a constant impact flux after 2.83 Ga. This newly calibrated chronology model improves the age estimation tool based on crater statistics for both the Moon and other terrestrial bodies, and also has additional implications for the evolution of lunar impactors, potentially related with early planet migration in the early Solar System.
This work was financially supported by the Chinese Academy of Sciences and the lunar research program of GIGCAS.

Figure 2 The two types of basalts in Chang’e-6 soils and isochrons of the Chang’e-6 low-Ti basalt.

Figure 3 Initial Pb and Sr-Nd isotopes of lunar basalts.

Figure 4 Incorporating the Chang’e-6 landing site into a lunar crater chronology model.

Credit

Image by GIGCAS

Journal

Science

DOI

10.1126/science.adt1093 

Article Title

A sample of the Moon's far side retrieved by Chang'e-6 contains 2.83-billion-year-old basalt

Article Publication Date

15-Nov-2024

Chang’e-6 basalts offer insights on lunar farside volcanism

Chinese Academy of Sciences Headquarters

 

image: 

Distribution of distinct volcanic episodes on the Moon’s farside. The remote sensing image highlights the Chang’e-6 landing site along with nearby mare and cryptomare basaltic units.

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Credit: Image by YANG Muhan

Basalt samples returned by the Chang’e-6 mission have revealed volcanic events on the lunar farside at 2.8 billion years ago (Ga) and 4.2 Ga, according to research conducted by Prof. LI Qiuli’s lab at the Institute of Geology and Geophysics of the Chinese Academy of Sciences. This work was recently published in Nature.

“Unraveling the volcanic history of the lunar farside is crucial for understanding the hemispheric dichotomy of the Moon,” said Prof. LI.

The asymmetry between the Moon’s nearside and farside—encompassing differences in basalt distribution, topography, crustal thickness, and thorium (Th) concentration—has long been a mystery. However, China’s Chang’e-6 mission—the first to return samples from the lunar farside—has created a unique opportunity to explore volcanic activity in this hemisphere, with the 1,935.3 g lunar soil sample it retrieved.

Led by Prof. LI, postdoctoral researcher ZHANG Qian conducted systematic radioisotope dating on 108 basalt fragments from this sample. Of these, 107 fragments revealed a consistent formation age of 2807 ± 3 million years ago (Ma), indicating the eruption age of local basalts at the Chang’e-6 landing site. Notably, this 2.8 Ga volcanic episode has not been observed in nearside samples.

The remaining fragment, of high-aluminum basalt and dating to 4203 ± 4 Ma, is thought to have originated from a cryptomare region south of the landing site. It is the oldest lunar basalt sample yet returned whose age has been precisely determined.

These data indicate that volcanic activity on the lunar farside persisted for at least 1.4 billion years, from 4.2 Ga to 2.8 Ga. Initial lead isotope analysis suggests that these basalts derive from distinct mantle sources: The 4.2 Ga basalt came from a KREEP-rich source, i.e., one with abundant potassium (K), rare earth elements (REE), and phosphorous (P), while the 2.8 Ga basalt came from a KREEP-poor source.

The close alignment between the 2.8 Ga basalt age and crater-counting estimates suggests that the cratering chronology model, established based on nearside observations, is also applicable to the lunar farside. The radioisotope ages of the Chang’e-6 basalts provide an essential calibration point for refining lunar crater-counting chronology, thus enhancing its accuracy, according to Prof. LI.

This research was conducted in collaboration with the National Astronomical Observatories, with samples provided by the China National Space Administration. Funding was provided by the National Natural Science Foundation of China, the Strategic Priority Research Program (Category B) of the Chinese Academy of Sciences, and the Key Research Program of the Institute of Geology and Geophysics, Chinese Academy of Sciences.

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Journal

Nature

DOI

10.1038/s41586-024-08382-0 

Article Title

Lunar farside volcanism 2.8 billion years ago from Chang’e-6 basalts

Article Publication Date

15-Nov-2024

 

Rainforest protection reduces the number of respiratory diseases

Study by the University of Bonn shows that deforestation in the Amazon region is also detrimental to human health

University of Bonn

Rainforest protection is not only good for biodiversity and the climate – it also noticeably improves the health of humans who live in the corresponding regions. This is the conclusion drawn by a current study by the University of Bonn and the Universidade Federal de Minas Gerais in Brazil. In this, the researchers show that measures to combat slash-and-burn techniques significantly reduce the concentration of particulate matter in the air. The number of hospital stays and deaths due to respiratory diseases thus also decreases. The results have been published now in the journal Nature Communications, Earth & Environment.

In 2019, almost 70,000 square kilometers of forest were burned in the Amazon region – this equates to an area the size of Bavaria. Natural fires are normally rare in the damp conditions that prevail there. However, major landowners and landgrabbers often clear huge areas to use them as pastures or for arable farming.

This overexploitation of Brazil’s green lung destroys the habitats of many species of flora and fauna and also accelerates climate change. However, the current study also takes into account another consequence that is often not given enough attention: The smoke generated during the fires is an important trigger of respiratory and cardiovascular diseases.

“We have thus investigated to what extent forest protection measures affect the health of people living in the corresponding regions,” explains Yannic Damm. The scientist is a member of Prof. Dr. Jan Börner’s research group at the Institute for Food and Resource Economics (ILR) at the University of Bonn. He conducted the study together with his ILR colleague Dr. Nicolas Gerber and with Prof. Dr. Britaldo Soares-Filho from the Universidade Federal de Minas Gerais in Brazil.

How does forest protection affect human health?

The Amazon region of Brazil is divided into two different zones: The legally defined Amazon, which follows the borders of the Amazonian states, and what is known as the Amazon biome, which follows the original forest boundary. “Between 2004 and 2010, a whole range of laws were adopted to curb the ongoing deforestation throughout the Amazon region,” says Damm. “However, in our study, we concentrated on three measures that exclusively apply within the Amazon biome and came into force from 2006.”

The most well-known of these three measures is presumably the Soy Moratorium. In this, globally operating trading companies agreed to no longer purchase soy grown in freshly deforested areas. “As a result, deforestation pressure has measurably reduced,” explains Damm. However, the moratorium (along with the other two resolutions investigated) only applies to the Amazon biome, but not to the neighboring Legal Amazon region with a lower protection status.

The researchers made use of this fact: They compared several hundred municipalities on the biome border with neighboring regions that lay outside of this border and to which the three measures did not, therefore, apply. “In this way, we were able to identify what effect the increased protection efforts had on public health,” highlights Damm. The group evaluated, among other things, the particulate matter pollution in the air, and analyzed the reasons why people in the investigated regions were taken to hospital or died.

Protective measures save 680 human lives per year

The effects of forest protection measures on each of these parameters were clear. The concentration of fine dust particles in the air fell in all of the investigated regions after 2006. However, this decrease was almost 7 percent higher in the municipalities within the biome borders. The number of hospital treatments and deaths due to respiratory and cardiovascular diseases also fell. Around four million men, women, and children live in the regions in which the three measures were established. The researchers estimate that around 680 human lives in this group were saved each year thanks to the reduced air pollution.

“Our study has two messages,” explains ILR researcher Prof. Dr. Jan Börner, who is also a member of the Transdisciplinary Research Area (TRA) Sustainable Futures and the Cluster of Excellence “PhenoRob” at the University of Bonn. “Namely, firstly, that the destruction of the rainforest can be successfully curbed. And, secondly, that this benefits not only the diversity of species and the global climate but also very specifically and very quickly the local population. This is an aspect that is still given too little consideration when assessing protective measures.”

Participating institutions and funding:

The University of Bonn and the Universidade Federal de Minas Gerais in Brazil took part in the study. The work was supported with funding from the German Research Foundation (DFG), the German Federal Ministry of Education and Research (BMBF), and the EU research and innovation program Horizon Europe.

Journal

Communications Earth & Environment

DOI

10.1038/s43247-024-01840-7 

Method of Research

Data/statistical analysis

Subject of Research

People

Article Title

Health benefits of reduced deforestation in the Brazilian Amazon

Article Publication Date

15-Nov-2024

 

Recycling batteries with citric acid

Highly efficient recycling process for NCM lithium-ion batteries

Wiley

A simple, highly efficient, inexpensive, and environmentally friendly process could provide a viable pathway for the sustainable recycling of depleted lithium-ion batteries (LIBs): No chemicals beyond citric acid need to be added to leach out and separate over 99 % of the lithium, nickel, cobalt, and manganese metals contained in NCM batteries. The resulting recycled material can be directly converted into NCM electrodes, reports a research team in the journal Angewandte Chemie.

From smartphones to electric vehicles, lithium-ion batteries are everywhere in our daily lives. They are also an important component of our transition to renewable energy, as they are used to store excess solar and wind energy and send it back into the power grid on demand. The downside is that their limited lifespan results in vast numbers of spent LIBs that contain dangerous heavy metals and other hazardous materials. In addition, metal resources are being depleted.

Most recycling processes suffer from high energy usage, high emissions, and limited or low-quality recovered material. Or they require very large amounts of chemicals, are complicated and expensive, and produce toxic gases and run-off. Leaching with biocompatible acids like citric acid is one alternative to these processes. However, conventional processes (chelation-gel process) require a significant excess of the acid, and the pH value must constantly be adjusted with ammonia—complicated and not very environmentally friendly.

A team at China University of Mining and Technology (Beijing), Fuzhou University, Beijing University of Chemical Technology, and Tsinghua University, Shenzhen (China) led by Guangmin Zhou and Ruiping Liu has now developed a novel citric-acid-based method for the leeching, separation, and reclamation of metals from NCM cathodes. NCM is a mixed oxide containing nickel, cobalt, and manganese in a lamellar structure. Lithium ions are enclosed between the layers.

The trick to their method: Instead of leeching with an excess of citric acid like conventional methods, they use a relatively small amount. Because of this, only two of the three acid groups in the citric acid dissociate. The released protons break up the lithium-oxygen bonds, releasing lithium ions from the NCM into the solution. Bonds between the other metal ions and the oxygen ions are also broken. Nickel, cobalt, and manganese enter the solution, where they are bound into stable complexes by the citric acid anions. The third acid group of the citric acid then reacts with the hydroxyl group on the same molecule. A ring closure occurs in an intramolecular esterification (Fischer lactonization) reaction. This facilitates the reaction of the intermediates with each other to make a polyester, which gels into solid particles that can easily be separated out. Energy consumption and CO2 emissions are significantly less than in conventional hydrometallurgical recycling processes.

The gel can subsequently be heated to burn off the organic fragment. This results in a new NCM lamellar framework with included lithium ions, which can be used as a high-quality electrode material.

(3235 characters)

About the Author

Dr Ruiping Liu is Professor at the School of Chemical and Environmental Engineering at China University of Mining and Technology (Beijing). His major research mainly focused on the synthesis of functional materials, and their applications in batteries and catalysts.

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Journal

Angewandte Chemie International Edition

DOI

10.1002/anie.202414484 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

The Fischer-Lactonization-Driven Mechanism for Ultra-Efficient Recycling of Spent Lithium-Ion Batteries

 

One or many? Exploring the population groups of the largest animal on Earth

University of Washington

 

Hunted nearly to extinction during 20th century whaling, the Antarctic blue whale, the world’s largest animal, went from a population size of roughly 200,000 to little more than 300. The most recent estimate in 2004 put Antarctic blue whales at less than 1% of their pre-whaling levels.

But is this population recovering? Is there just one population of Antarctic blue whales, or multiple? Do these questions matter for conservation?

A team led by Zoe Rand, a University of Washington doctoral student, tackles these questions in a study, published Nov. 14 in Endangered Species Research. Building on the last assessment of Antarctic blue whales in 2004 and using old whaling records, which were surprisingly detailed, Rand and her colleagues investigated if the Antarctic blue whales consist of different populations or are one big circumpolar population. Study co-authors are Trevor Branch, a UW professor of aquatic and fishery sciences, and Jennifer Jackson from the British Antarctic Survey.

Antarctic blue whales are listed as an endangered species, and understanding their population structure is essential for their conservation. Conservation at the population-level increases biodiversity, which helps the species adapt better to environmental changes and increases chances of long-term survival.

During the whaling years, biologists began the Discovery Marking Program. Foot-long metal rods with serial numbers were shot into the muscles of whales. When these whales were caught, the metal rod was returned, and the whale’s size, sex, length and location where it was caught was noted. Looking at where whales were marked compared to where they were caught could shed valuable insight into the movement of Antarctic blue whales, but these data have never been used before to look at population structure.

In this new study, this historical data were used alongside contemporary survey data in Bayesian models to calculate inter-annual movement rates among the three ocean basins that make up the Southern Ocean — Atlantic, Indian and Pacific — which make up the feeding grounds for Antarctic blue whales. The team found frequent mixing among the ocean basins, suggesting that whales do not return to the same basin every year. This points to Antarctic blue whales being one single circumpolar population in the Southern Ocean.

These results are consistent with studies of Antarctic blue whale songs, heard throughout the Southern Ocean. Only one song type has been recorded among the Antarctic blue whales. In comparison, pygmy blue whales have five different songs corresponding to five different populations. These results are also consistent with genetic studies, which found that Antarctic blue whales are more closely related than would be expected if they were separate populations.

This study is the first time that historical mark-recovery data from the Discovery Marking Program has been analyzed using modern quantitative methods. These data exist for many other hunted whale species, such as fin and sei whales, so the new study’s methods could provide a framework for similar analyses for those whale species too.

There is still a lot scientists don’t know about the Antarctic blue whale. Even though they do not appear to be separated geographically on their feeding waters in different ocean basins, they could still have distinct population structures based on differences in breeding habitats or the timing of migration. However, almost nothing is known about Antarctic blue whale breeding behavior, according to the researchers. Using historical data from whaling alongside contemporary data — such as satellite tagging and photo-identification — remains scientists’ best hope for uncovering the secrets of the largest animal on Earth.

The research was funded by the International Whaling Commission’s Southern Ocean Research Partnership.

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For more information, contact Rand at zrand@uw.edu and Branch at tbranch@uw.edu.

Text by Niamh Owen-McLaughlin.

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Journal

Endangered Species Research

DOI

10.3354/esr01361 

Method of Research

Meta-analysis

Subject of Research

Animals

Article Title

High historical movement rates of Antarctic blue whales on Southern Ocean feeding grounds estimated from Discovery mark data

Article Publication Date

14-Nov-2024