Tag: Environment

Researchers Produce Highly Efficient, Low-cost “Green” Hydrogen

Written by AUFTAU on 17 July 2023. Posted in Newsroom.

Tel Aviv University researchers have achieved a groundbreaking milestone by successfully producing highly efficient and low-cost “green” hydrogen. By harnessing the power of green electricity and utilizing a highly efficient biocatalyst, this innovative process generates hydrogen without any air pollution.

Hydrogen plays a vital role as raw material in both agriculture and industry. However, most of the hydrogen produced globally, approximately 95%, falls in the “black” or “gray” category. These types of hydrogen are derived from coal or natural gas, emitting a significant 9-12 tons of carbon dioxide for every ton of hydrogen produced.

Over 90% Efficiency

The new method was developed by doctoral student Itzhak Grinberg and Dr. Oren Ben-Zvi, under the guidance of Prof. Iftach Yacoby of the School of Plant Sciences and Food Security at the Faculty of Life Sciences and Prof. Lihi Adler-Abramovich of the School of Dental Medicine and the Center for Nanoscience and Nanotechnology. The promising research results were published in the prominent journal Carbon Energy, focusing on advanced materials and technology for clean energy and CO2 emission reduction.

“Hydrogen is very rare in the atmosphere,” explains Itzhak Grinberg, “although it is produced by enzymes in microscopic organisms, which receive the energy for this from photosynthesis processes. In the lab, we ‘electrify’ those enzymes, that is, an electrode provides the energy instead of the sun. The result is a particularly efficient process, with no demand for extreme conditions, that can utilize electricity from renewable sources such as solar panels or wind turbine. However, the enzyme ‘runs away’ from the electric charge, so it needs to be held in place through chemical treatment. We found a simple and efficient way to attach the enzyme to the electrode and utilize it.”

The researchers used a hydrogel (a water-based gel) to attach the enzyme to the electrode and were able to produce green hydrogen using a biocatalyst, and with over 90% efficiency; that is, over 90% of the electrons introduced into the system were deposited in the hydrogen without any secondary processes.

“We hope that in the future, it will be possible to employ our method commercially, to lower the costs, and to make the switch towards using green hydrogen in industry, agriculture, and as a clean energy source.” – Dr. Oren Ben-Zvi

Prof. Iftach Yacoby explains that, “The material of the gel itself is known, but our innovation is to use it to produce hydrogen. We soaked the electrode in the gel, which contained an enzyme for producing hydrogen, called hydrogenase. The gel holds the enzyme for a long time, even under the electric voltage, and makes it possible to produce hydrogen with great efficiency and at environmental conditions favorable to the enzyme — for example, in salt water, in contrast to electrolysis, which requires distilled water.

Prof. Lihi Adler-Abramovich adds: “Another advantage is that the gel assembles itself — you put the material in water, and it settles into nanometric fibers that form the gel. We demonstrated that these fibers are also able to stick the enzyme to the electrode. We tested the gel with two other enzymes, in addition to the hydrogenase, and proved that it was able to attach different enzymes to the electrode.”

“Today, ‘green’ hydrogen is produced primarily through electrolysis, which requires precious and rare metals such as platinum along with water distillation, which makes the green hydrogen up to 15 times more expensive than the polluting ‘grey’ one, says Dr. Oren Ben-Zvi. “We hope that in the future, it will be possible to employ our method commercially, to lower the costs, and to make the switch towards using green hydrogen in industry, agriculture, and as a clean energy source.”

Due to Climate Change, More Animals will Become Extinct Outside of Nature Reserves than Within Them

Written by AUFTAU on 12 July 2023. Posted in Newsroom.

A new international study has found that amphibians and reptiles inhabiting the world’s nature reserves, or Protected Areas (PAs), will be better protected against climate change than species found outside of these areas, but are still likely to be harmed.

The research findings provide evidence, on a global scale, of the crucial role Protected Areas play in conserving amphibian and reptile biodiversity under human-induced climate change scenarios. The study reveals that more animals will become extinct because of climate change outside of Protected Areas than inside them — in the world in general and on most individual continents.

Protected Areas as Refuges

Prof. Shai Meiri of Tel Aviv University’s School of Zoology, The George S. Wise Faculty of Life Sciences and The Steinhardt Museum of Natural History took part in the study, in collaboration with leading researchers from 19 countries. The study was published in the prestigious journal Nature Communications.

“Approximately 91% of the amphibian and reptile species we examined are protected, to some degree, in Protected Areas, and this proportion will remain unchanged under future climate change.” – Prof. Shai Meiri

The purpose of the study was to evaluate the effectiveness of existing Protected Areas in protecting the amphibians and reptiles living within them under future climate scenarios, as well as to identify conservation gaps in order to outline a road map for the development of conservation actions based on the current global network of Protected Areas.

“In this study, we collected distribution data for more than 14,000 species of amphibians and reptiles — about 70% of the known species — to perform a global assessment of the conservation effectiveness of Protected Areas in an era of climate change, using species distribution models,” explains Prof. Meiri. “Our analyses revealed that approximately 91% of the amphibian and reptile species we examined are protected, to some degree, in Protected Areas, and that this proportion will remain unchanged under future climate change. Furthermore, species protected in Protected Areas will lose smaller portions of their distribution ranges inside the nature reserve than outside of them. Therefore, the proportion of species within reserves is expected to increase.”

Relative Optimism

However, Prof. Meiri points out, “We predict that more than 300 of the amphibian species and 500 of the reptile species we studied will become extinct due to climate change in the coming decades, and probably also hundreds of species for which we did not have sufficient data to model. Our research highlights the importance of Protected Areas in providing refuge for amphibians and reptiles in face of climate change and points out areas where there are not enough nature reserves that can better preserve biodiversity around the world.”

“Despite the relative optimism emerging from the new research, the models still predict extremely high rates of loss of species and habitats due to climate change. Protected Areas do indeed protect the animals living within them, but nothing is foolproof.” – Prof. Shai Meiri

He adds: “We compiled a comprehensive global database with more than 3.5 million observation records spanning 5,403 amphibian species and 8,993 reptile species from online databases, fieldwork data, museum collections, and published references. For all species in our database, we predicted habitat availability according to current (1960–1990) climate data and future scenarios (for the years 2060–2080) at a high spatial resolution (1 km × 1 km) using species distribution models. Then, we evaluated the effectiveness of Protected Areas in conserving amphibians and reptiles by calculating the coverage of their distribution range inside and outside of Protected Areas, as well as the proportion of species for whom a significant portion of their distribution range (for example, 15% or 30%) is protected in PAs under current and future climate conditions (assuming that the future use of the land remains unchanged over the years — that is, that there will be no conversion of nature reserves into agricultural, industrial, or urban areas.)”

Prof. Meiri concludes: “Our evidence shows that the current global network of Protected Areas already plays an important role in preserving the global biodiversity of amphibians and reptiles, and will continue to do so under the expected future climate. However, many species do not live in the existing Protected Areas. These include, for example, many amphibians and reptiles in Mexico, Jamaica, the Andes, West Africa, South Africa, the southern and northern coast of Turkey, Yemen and other places. Moreover, in our study we could create a model for only about two-thirds of reptile and amphibian species. Good models can’t be created for the rarest species, which are known to be more vulnerable to extinction and less protected in Protected Areas. At the same time, it is important to remember that despite the relative optimism emerging from the new research, the models still predict extremely high rates of loss of species and habitats due to climate change. Protected Areas do indeed protect the animals living within them, but nothing is foolproof.”

New Studies Expose Coral Reef Crisis in Eilat

Written by AUFTAU on 28 May 2023. Posted in Newsroom.

Recent, unsettling studies conducted by Tel Aviv University have unveiled a deadly epidemic responsible for the widespread decimation of black sea urchins in the Mediterranean Sea and the Gulf of Eilat. Over the span of just a few months, the entire population of black sea urchins in Eilat was eradicated. For instance, within a few weeks, thousands of sea urchins inhabiting a site near the northern shore of the Gulf of Eilat perished. The severity of the epidemic is such that only skeletal remains of black urchins now occupy the site. Disturbingly, similar occurrences have been observed at various other locations in the Gulf of Eilat, as well as in neighboring countries including Jordan, Egypt, Saudi Arabia, Greece, and Turkey.

“At first we thought it was some kind of pollution or poisoning, or a local chemical spill (…) but when we examined additional sites in Eilat, Jordan, and Sinai, we quickly realized that this was not a local incident. All findings pointed to a rapidly spreading epidemic.” – Dr. Omri Bronstein.

Unveiling Deadly Epidemic

The studies were led by Dr. Omri Bronstein and PhD students Rotem Zirler, Lisa-Maria Schmidt, Gal Eviatar, and Lachan Roth from the School of Zoology, at The George S. Wise Faculty of Life Sciences, and The Steinhardt Museum of Natural History at Tel Aviv University. The papers were published in Frontiers in Marine science and Royal Society Open Science.

The researchers underscore the vital importance of sea urchins, particularly the long-spined Diadema setosum, as keystone species essential for the thriving equilibrium of coral reefs. They express a pressing concern, stating, “It must be understood that the threat to coral reefs is already at an all-time peak, and now a previously unknown variable has been added. This situation is unprecedented in the documented history of the Gulf of Eilat.”

According to the researchers’ hypothesis, the cause of the deadly epidemic can be attributed to a pathogenic ciliate parasite that has spread from the Mediterranean to the Red Sea. In response to the gravity of the situation, an urgent report outlining the current state has been submitted to the Israel Nature and Parks Authority, instigating deliberation on emergency measures to safeguard Israel’s coral reefs.

“Sea urchins in general, and Diadema setosum in particular, are considered key species essential for the healthy functioning of coral reefs. The sea urchins are the reef’s ‘gardeners’ – they feed on the algae and prevent them from taking over and suffocating the corals that compete with them for sunlight.” – Dr. Omri Bronstein

Dr. Omri Bronstein and a dying sea urchin

“At first we thought it was some kind of pollution or poisoning, or a local chemical spill, from the industry and hotels in the north of the Gulf of Eilat, but when we examined additional sites in Eilat, Jordan, and Sinai, we quickly realized that this was not a local incident,” explains Dr. Bronstein. “All findings pointed to a rapidly spreading epidemic. Similar reports are coming in from colleagues in Saudi Arabia. Even sea urchins that we grow for research purposes in our aquariums at the Interuniversity Institute, and sea urchins at the Underwater Observatory Marine Park in Eilat, contracted the disease and died, probably because the pathogen got in through the pumping systems.”

Dr. Bronstein describes it as a fast and violent death: “Within just two days a healthy sea urchin becomes a skeleton with massive tissue loss. While some corpses are washed ashore, most sea urchins are devoured while they are dying and unable to defend themselves, which could speed up contagion by the fish who prey on them.”

Invasion and Vanishing Species

In recent years, Dr. Bronstein’s research group has dedicated their efforts to the investigation of marine invasions, with a specific focus on the long-spined Diadema setosum. “Until recently, the black sea urchins with long spines, familiar to many of us, was one of the dominant species in Eilat’s coral reef,” reflects Dr. Bronstein. “Sea urchins in general, and Diadema setosum in particular, are considered key species essential for the healthy functioning of coral reefs. The sea urchins are the reef’s ‘gardeners’ – they feed on the algae and prevent them from taking over and suffocating the corals that compete with them for sunlight. Regrettably, these once-thriving sea urchins have vanished from the Gulf of Eilat and are quickly disappearing from constantly expanding parts of the Red Sea further to the south,” shares Dr. Bronstein with a sense of lament.

A dying urchin in the Mediterranean Sea (photo: Dr. Omri Bronstein)

Several months ago, Dr. Bronstein was alerted to the initial reports of widespread mortality by colleagues in Greece and Turkey, where the sea urchins had invaded, likely via the Suez Canal. “In 2006, the first sighting of this species of sea urchin occurred in the southern regions of Turkey,” Dr. Bronstein adds. This phenomenon, known as biological invasion, carries far-reaching ecological implications, pervasively affecting the eastern Mediterranean, particularly along Israel’s coastline. “We have been monitoring the dynamics of this species’ invasion in the Mediterranean since its first emergence,” he shares.

In 2016, they discovered the first Diadema setosum sea urchin along Israel’s Mediterranean coastline – a lone urchin sighted at Gordon Beach in Tel Aviv. For over a decade since the first discovery in Turkey, the Mediterranean populations of these sea urchins remained small and usually hidden. However, since 2018 the sea urchin population in the Mediterranean has been growing exponentially, reaching a state of population explosion – with giant populations of thousands and even tens of thousands found in Greece and Turkey.

“The window of opportunity for preserving a thriving population of this species in Eilat has regrettably closed. To establish a safeguard population, we must act without delay, by preserving healthy individuals from the Israeli Mediterranean before the encroaching disease from the north reaches this region.” Dr. Omri Bronstein

“However, during the course of our research, while scrutinizing the invasion of sea urchins in the Mediterranean, we began to receive reports on sudden extensive mortality,” says Dr. Bronstein. “While the extinction of an invasive species is supposedly not a bad thing, we must be aware of two major risks: Firstly, we don’t yet know how this mortality and its causes might impact local species in the Mediterranean. Secondly, and of far greater significance, the geographic proximity shared by the eastern Mediterranean and the Red Sea provides a potential conduit for the swift transmission of the pathogen into the Red Sea. As we feared and predicted, this is what appears to have happened.”

Dr. Bronstein and his research team (photo: courtesy of Dr. Omri Bronstein)

A Reminiscent Crisis

The massive loss of sea urchins reminded the TAU researchers of one of the most devastating events in marine ecology: the disappearance of the sea urchins in the Caribbean. Until 1983, the Caribbean coral reef thrived as a vibrant tropical ecosystem, much like the one in the Gulf of Eilat. But as the sea urchins vanished, the uncontrollable growth of algae took over, blocking sunlight from reaching the corals and forever altering the reef into a sea of algae.

Dr. Bronstein reveals, “Just last year, the Caribbean experienced another outbreak of the disease, resulting in the demise of the remaining urchin populations. However, unlike previous incidents, we now possess advanced scientific and technological resources to analyze the forensic evidence. Researchers from Cornell University successfully pinpointed the cause of mortality in the Caribbean: a pathogenic ciliate parasite. The identical pathology observed in the dying sea urchins of Greece, Turkey, and the Red Sea corroborates this finding.”

Dr. Bronstein’s pioneering research not only identified the unprecedented mass mortality of an invasive species in the Mediterranean but also shed light on the alarming decline of the widely prevalent sea urchin species, Diadema setosum. In a groundbreaking study, Dr. Bronstein issued a a warning that the epidemic plaguing the Mediterranean could extend its reach to the nearby Red Sea. Sadly, this cautionary prediction has become a disheartening reality.

Urgent Measures and Closing Window

“The gravity of the situation cannot be understated: the Red Sea is witnessing an alarming surge in mortality, surpassing the extent observed in the Mediterranean. Looming in the background is an ominous uncertainty: What is the exact cause of the sea urchin die-offs? Is it the same Caribbean pathogen or an entirely new and unfamiliar factor? Regardless, it is evident that this pathogen spreads through water, and we anticipate a rapid escalation of sickness and demise among the entire population of these sea urchins in both the Mediterranean and the Red Sea.”

“In my view, it is imperative that we swiftly establish a safeguard population for these sea urchins, ensuring the potential for their reintroduction into the wild. Similar to the approach taken with COVID-19, the trajectory of this epidemic remains uncertain. Will it eventually subside on its own, or persist for years, radically transforming coral reefs? However, unlike the COVID-19 pandemic, there are no available vaccines or treatments for the afflicted sea urchins. Hence, our efforts must be steadfastly directed towards prevention. The window of opportunity for preserving a thriving population of this species in Eilat has regrettably closed. To establish a safeguard population, we must act without delay, by preserving healthy individuals from the Israeli Mediterranean before the encroaching disease from the north reaches this region. While this is a complex undertaking, it is imperative if we aspire to secure the future of this unique species, which plays a critical role in the destiny of coral reefs,” concludes Dr. Bronstein.

Plants Emit Sounds – Especially When Stressed

Written by AUFTAU on 1 April 2023. Posted in Newsroom.

In a world first, Tel Aviv University researchers record and analyze sounds distinctly emitted by plants.

Do you talk to your plants? While you may not be able to hear them, yaour plants could very well be chatting away as well (perhaps they are not such great listeners after all), and that’s especially true if they are having a bad day (did you forget to water them again?). For the first time in the world, TAU researchers recorded and analyzed sounds distinctly emitted by plants. The click-like sounds, resembling the popping of popcorn, are emitted at a volume similar to human speech, but at high frequencies, beyond the hearing range of the human ear. The researchers: “We found that plants usually emit sounds when they are under stress, and that each plant and each type of stress is associated with a specific identifiable sound. While imperceptible to the human ear, the sounds emitted by plants can probably be heard by various animals, such as bats, mice, and insects.”

“From previous studies we know that vibrometers attached to plants record vibrations, but do these vibrations also become airborne soundwaves – sounds that can be recorded from a distance? Our study addressed this question, which researchers have been debating for many years.” Prof. Lilach Hadany

Resolving Old Scientific Controversy

The study was led by Prof. Lilach Hadany from the School of Plant Sciences and Food Security at The George S. Wise Faculty of Life Sciences, together with Prof. Yossi Yovel, Head of the Sagol School of Neuroscience and faculty member at the School of Zoology and the Steinhardt Museum of Natural History, and research students Itzhak Khait and Ohad Lewin-Epstein, in collaboration with researchers from the Raymond and Beverly Sackler School of Mathematical Sciences, the Institute for Cereal Crops Research, and the Sagol School of Neuroscience – all at Tel Aviv University. The paper was published in the prestigious scientific journal Cell.

“From previous studies we know that vibrometers attached to plants record vibrations,” says Prof. Hadany. “But do these vibrations also become airborne soundwaves – sounds that can be recorded from a distance? Our study addressed this question, which researchers have been debating for many years.”

WATCH: Prof. Yossi Yovel and Prof. Lilach Hadany on their findings

At the first stage of the study the researchers placed plants in an acoustic box in a quiet, isolated basement with no background noise. Ultrasonic microphones recording sounds at frequencies of 20-250 kilohertz (the maximum frequency detected by a human adult is about 16 kilohertz) were set up at a distance of about 10cm from each plant. The study focused mainly on tomato and tobacco plants, but wheat, corn, cactus and henbit were also recorded.

“Our findings suggest that the world around us is full of plant sounds, and that these sounds contain information – for example about water scarcity or injury (…) We believe that humans can also utilize this information, given the right tools – such as sensors that tell growers when plants need watering.” – Prof. Lilach Hadany

Mapping Plants’ Complaints with AI

Before placing the plants in the acoustic box, the researchers subjected them to various treatments: some plants had not been watered for five days, in some the stem had been cut, and some were untouched. Prof. Hadany explains that their intention was to test whether the plants emit sounds, and whether these sounds are affected in any way by the plant’s condition: “Our recordings indicated that the plants in our experiment emitted sounds at frequencies of 40-80 kilohertz. Unstressed plants emitted less than one sound per hour, on average, while the stressed plants – both dehydrated and injured – emitted dozens of sounds every hour.”

The recordings collected in this way were analyzed by specially developed machine learning (AI) algorithms. The algorithms learned how to distinguish between different plants and different types of sounds, and were ultimately able to identify the plant and determine the type and level of stress from the recordings. Moreover, the algorithms identified and classified plant sounds even when the plants were placed in a greenhouse with a great deal of background noise.

In the greenhouse, the researchers monitored plants subjected to a process of dehydration over time and found that the quantity of sounds they emitted increased up to a certain peak, and then diminished.

“In this study we resolved a very old scientific controversy: we proved that plants do emit sounds!” says Prof. Hadany. “Our findings suggest that the world around us is full of plant sounds, and that these sounds contain information – for example about water scarcity or injury. We assume that in nature the sounds emitted by plants are detected by creatures nearby, such as bats, rodents, various insects, and possibly also other plants – that can hear the high frequencies and derive relevant information. We believe that humans can also utilize this information, given the right tools – such as sensors that tell growers when plants need watering. Apparently, an idyllic field of flowers can be a rather noisy place. It’s just that we can’t hear the sounds.”

In future studies the researchers will continue to explore a range of intriguing questions, such as: What is the mechanism behind plant sounds? How do moths detect and react to sounds emitted by plants? Do other plants also hear these sounds? Stay tuned.

The research team

Does a Food Sharing Economy Benefit the Environment?

Written by AUFTAU on 14 February 2023. Posted in Newsroom.

According to researchers it depends on how the saved money is spent.

Researchers from Tel Aviv University and Ben Gurion University explored the true benefit of the so-called “digital food sharing economy”: when people advertise and pass on surplus food items to others instead of throwing them away. Is this indeed an environmentally friendly practice that saves resources and significantly reduces harm to the environment? The researchers focused on the effectiveness of food sharing according to three environmental indicators: water depletion, land use, and global warming. They found that a significant proportion of the benefit to the environment is offset when the money saved is then used for purposes that have a negative environmental impact.

“While there is nothing new about sharing food, digitalization has lowered transaction costs substantially, allowing food to be shared not only within social circles of family and friends but also with absolute strangers.” Dr. Tamar Makov

Sharing Food Got Cheaper

The study was led by Tamar Meshulam, under the guidance of Dr. Vered Blass of the Porter School of Environment and Earth Sciences at the Raymond & Beverly Sackler Faculty of Exact Sciences of Tel Aviv University and Dr. Tamar Makov of Ben-Gurion University, and in collaboration with Dr. David Font-Vivanco, an expert on “rebound effect.” The article won the award for the “Best Article” at the PLATE (Product Lifetimes and the Environment) conference and was published in the Journal of Industrial Ecology.

“Food waste is a critical environmental problem,” explains Tamar Meshulam: “We all throw away food, from the farmer in the field to the consumer at home. In total, about a third of the food produced in the world is lost or wasted. This wasted food is responsible for roughly 10% of GHG [greenhouse gas] emissions, and the land area used to grow food that is then wasted is equal in size to the vast territory of Canada! That’s why it is so important to look for ways to reduce food waste and examine their potential contribution to mitigating climate change.”

According to Dr. Tamar Makov, “Internet platforms for sharing food are gaining popularity all over the world and are seen as a natural solution that can help tackle both food waste and food insecurity at the same time. While there is nothing new about sharing food, digitalization has lowered transaction costs substantially, allowing food to be shared not only within social circles of family and friends but also with absolute strangers.”

“Is it possible that at least some of the money saved is then spent on carbon intensive products and services that negate the benefit of sharing? (…) In this study, we sought to examine this troubling issue in depth.” Dr. Vered Blass

From left to right: Dr. Vered Blass (Tel Aviv University) and Dr. Tamar Makov (Ben-Gurion University)

Where Does the Money Go?

“At the same time, sharing platforms as well as other digitally enabled food waste reduction platforms (e.g., too good to go) can save users a lot of money, which raises the question of what do people typically do with such savings? Considering what people do with the money they save via sharing platforms is critical for evaluating environmental impacts,” notes Makov.

Dr. Vered Blass adds: “Is it possible that at least some of the money saved is then spent on carbon intensive products and services that negate the benefit of sharing?” She offers an example to illustrate: “Let’s say that for one month a young couple lives only on food they obtained for free through a sharing platform, and then they decide to use the money they saved to fly abroad. In such a case, it’s obvious that the plane they will be flying in creates pollution that harms the environment more than all the benefits of sharing. In this study, we sought to examine this troubling issue in depth.”

“As long as our savings are measured in money, and the money is used for additional expenses, the rebound effect will erode our ability to reduce environmental burdens through greater efficiency.” The research team

“Rebound Effect” Detected

The researchers chose to focus on the app OLIO, an international peer-to-peer food-sharing platform, and specifically on its activity in the United Kingdom between the years 2017 and 2019.

Combining models from the fields of industrial ecology, economics, and data science, they measured the benefits of sharing food using three environmental indicators: global warming, the depletion of water sources, and land use. To understand how OLIO users spend their savings they used statistical data published by the UK Office for National Statistics on household spending by consumption purpose to as COICOP (classification of individual consumption according to purpose).

“The location in which the food-sharing took place allowed us to assign each collecting user to their UK income percentile,” shares Meshulam. “We found that about 60% of the app’s users belong to the bottom five deciles, while about 40% of the shares were carried out by the top five deciles. We also found that the second and tenth deciles made up a relatively large number of shares, so we chose to focus on them, along with data on the general population – what they spend their money on, and what the significance of these consumption habits is regarding the savings made possible by sharing.”

The researchers performed a variety of statistical analyses, which yielded fascinating findings. In many cases, there was a considerable gap, or “rebound effect” between the expected environmental benefit and the benefit that was attained.

This rebound effect changed depending on the population and the environmental impact category. Tamar Meshulam cites several examples: For the general population, 68% of the benefit was offset in the global warming category, about 35% was offset in the water depletion category, and about 40% was offset in the land use category. Furthermore, in households that used half of their savings on food, the rebound effect in all categories increased to 80-95%.

The researchers sum up: “The conclusion from our research is that the actual environmental benefits from efficiency improvements often fall short of expectations. This is because the infrastructures supporting human activities are still carbon intensive. As long as our savings are measured in money, and the money is used for additional expenses, the rebound effect will erode our ability to reduce environmental burdens through greater efficiency.”

The researchers also examined what the results would have been if the sharing had been conducted in 2011 (these results are not included in this article). A comparison with the findings of 2019 shows a significant improvement. The explanation for this is that in recent years, Britain has made great efforts to switch to renewable energies, and the impact of this is evident in the decrease of greenhouse gas emissions. The bottom line? The researchers conclude that “as our findings demonstrate, we need to combine a transition to green infrastructure with green consumerism. Each of these individually will not achieve the desired and critical impact needed for humanity and the planet.”

Featured image: Volunteers receive groceries for the elderly in Bat Yam, Israel during the coronavirus before the feast of Pesach (April 7, 2020) (Photo Credit: TAU)

Light Pollution is Killing Desert Rodents

Written by AUFTAU on 10 February 2023. Posted in Newsroom.

New study shows that artificial light at night can be harmful to ecosystems, biodiversity, and human health.

A new study from Tel Aviv University’s School of Zoology tested the impact of prolonged low-intensity light pollution on two species of desert rodents: the diurnal golden spiny mouse, and the nocturnal common spiny mouse. The findings were highly disturbing: on two different occasions, entire colonies exposed to ALAN (Artificial Light At Night) died within days, and reproduction also decreased significantly compared to control groups. According to the researchers, the results show clearly for the first time that light pollution can be extremely harmful to these species, and suggest they may be harmful to ecosystems, biodiversity, and even human health.

“According to latest studies, about 80% of the world’s human population is exposed to ALAN, and the area affected by light pollution grows annually by 2-6%. In a small and overcrowded state like Israel, very few places remain free of light pollution.” Hagar Vardi-Naim

Humans Changed the Rules

The study was led by Prof. Noga Kronfeld-Schor, Chief Scientist of Israel’s Ministry of Environmental Protection, and PhD student Hagar Vardi-Naim, both from TAU’s School of Zoology and the Steinhardt Museum of Natural History. The paper was published in Scientific Reports.

“We have been studying these closely related rodent species for years. They both live in Israel’s rocky deserts: the golden spiny mouse (Acomys russatus) is diurnal [active during the day], and the common spiny mouse (A. cahirinus) in nocturnal [active during the night],” explains Prof. Kronfeld-Schor. “The two species share the same natural habitat but use it at different times to avoid competition. By comparing closely related species that differ in activity times, we gain new insights into the biological clock and its importance to the health of both animals and humans.”

Hagar Vardi-Naim notes that, “in most species studied to date, including humans, the biological clock is synchronized by light. This mechanism evolved over millions of years in response to the daily and annual cycles of sunlight – day and night and their varying lengths that correspond to the change of seasons. Different species developed activity patterns that correspond to these changes in light intensity and daylength and developed anatomical, physiological and behavioral adaptations suitable for day or night activity and seasonality.”

“However, over the last decades, humans have changed the rules by inventing and extensively using artificial light, which generates light pollution. According to latest studies, about 80% of the world’s human population is exposed to ALAN, and the area affected by light pollution grows annually by 2-6%. In a small and overcrowded state like Israel, very few places remain free of light pollution. In our study, we closely monitored the long-term effects of ALAN on individuals and populations under semi-natural conditions.”

“We had seen no preliminary signs (…) We assume that exposure to ALAN had impaired the animals’ immune response, leaving them with no protection against some unidentified pathogen [organism causing disease to its host].” Prof. Noga Kronfeld-Schor

Prof. Noga Kronfeld-Schor

Dramatic Turn of Events

In the study, the researchers placed 96 spiny mice, males and females in equal numbers, in eight spacious outdoor enclosures at TAU’s Zoological Research Garden. The enclosures simulated living conditions in the wild: all animals were exposed to natural environmental conditions, including the natural light/dark cycle, ambient temperatures, humidity, and precipitation. Each enclosure contained shelters, nesting materials and access to sufficient amounts of food. The experimental enclosures were exposed to low-intensity ALAN (like a streetlamp in urban areas) of different wavelengths (colors) for 10 months: two enclosures were exposed to cold white light, two to warm white (yellowish) light, and two to blue light, while two of the enclosures remained dark at night and served as controls. All animals were marked to enable accurate monitoring of changes in behavior and physical condition. The experiment was conducted twice in two successive years.

“The average life expectancy of spiny mice is 4-5 years, and our original plan was to monitor the effects of ALAN on the same colonies, measuring the effects on reproductive output, wellbeing and longevity,” says Prof. Kronfeld-Schor. “But the dramatic results thwarted our plans: on two unrelated occasions, in two different enclosures exposed to white light, all animals died within several days. We had seen no preliminary signs, and autopsies at TAU’s Faculty of Medicine and the Kimron Veterinary Institute in Beit Dagan revealed no abnormal findings in the dead spiny mice. We assume that exposure to ALAN had impaired the animals’ immune response, leaving them with no protection against some unidentified pathogen. No abnormal mortality was recorded in any of the other enclosures, and as far as we are aware, no similar event has ever been documented by researchers before.”

“Our findings show that light pollution, especially cold white and blue light, increases mortality and disrupts reproduction, and thus may be detrimental to the fitness and survival of species in the wild. This adverse effect can have far-reaching consequences at the current wide distribution of light pollution.” Prof. Noga Kronfeld-Schor

Disrupted Reproduction

Other findings also indicated that exposure to ALAN disrupts the reproductive success of spiny mice: “In the wild both species of spiny mice breed mainly during summer, when temperatures are high, and the newborn pups are most likely to survive,” shares Hagar Vardi-Naim. “Artificial light, however, seemed to confuse the animals. The common spiny mice began to breed year-round but produced a lower number of pups per year. Pups born during winter are not expected to survive in nature, which would further reduce the species’ reproductive success in the wild.”

“The reproduction of golden spiny mice was affected in a different way: colonies exposed to ALAN continued to breed in the summer, but the number of young was reduced by half compared to the control group, which continued to thrive and breed normally. These findings are in accordance with the fact that in seasonal long day breeders the cue for reproduction is day length.”

Additional tests revealed that exposure to ALAN caused physiological and hormonal changes – most significantly in the level of cortisol, an important stress hormone involved in the regulation and operation of many physiological pathways, including the regulation of the immune system. Lab tests indicated that exposure to blue light increased cortisol levels of golden spiny mice, while white light reduced cortisol levels of golden spiny mice males in winter.

“Our findings show that light pollution, especially cold white and blue light, increases mortality and disrupts reproduction, and thus may be detrimental to the fitness and survival of species in the wild. This adverse effect can have far-reaching consequences at the current wide distribution of light pollution. Our clear results are an important step toward understanding the impact of light pollution on biodiversity and will help us promote science-based policies, specifically with regard to the use of artificial light in both built and open areas. In future studies we plan to investigate what caused the extensive deaths in the enclosures exposed to ALAN, focusing on the effect of light pollution exposure on the immune system,” concludes Prof. Kronfeld Schor.

Plastic Additives Harm Corals’ Reproductive Processes

Written by AUFTAU on 12 December 2022. Posted in Newsroom.

A new study by Tel Aviv University and the Interuniversity Institute for Marine Sciences in Eilat examined the effect of plastic additives on the reproductive process and larvae development of corals and other organisms commonly found in the coral reef of Eilat.

Plastic additives are chemicals that are added to plastic products during manufacturing, and many of them are known to be endocrine disrupting compounds. The current study shows that these chemicals can have species-specific effects that may damage the population structure and biodiversity of coral reefs.

The study was led by Ph.D. student Gal Vered of the Interuniversity Institute for Marine Sciences in Eilat and Tel Aviv University, and Prof. Noa Shenkar of Tel Aviv University’s School of Zoology in the George S. Wise Faculty of Life Sciences and the Steinhardt Museum of Natural History. The study was published in the prestigious journal Environmental Pollution.

The researchers focused on four organisms: a stony coral, a soft coral, a fire coral, and a solitary ascidian. These organisms play an important role in the ecology of tropical coral reefs, and damage to their reproduction and development may affect the structure of the reef community.

In addition, the researchers examined four chemical additives that are widely used in plastic products, and which have been found in seawater in tropical areas inhabited by coral reefs. Two of these were phthalate chemicals, which are used to soften and increase the flexibility of different types of plastic and can be found in a wide variety of consumer products such as food packaging, toys, medical devices, and adhesives. The others were 4-nonylphenol a stabilizer used in plastic packaging and as an additive in cleaning agents, and bisphenol A found in polycarbonate plastic that is used for food and beverage packaging, baby bottles, boxes, and more. The European Chemicals Agency has classified bisphenol A as a substance that may cause damage to human fertility, based on evidence found in laboratory animals.

“To better understand the impact of plastic additives on this endangered ecosystem, we suggest developing better methods for measuring the actual concentrations within the tissues of the organisms to produce relevant risk assessments.” Prof. Noa Shenkar

Selective Effect on Different Species

“Plastic additives are chemical additives that are incorporated into plastic products during the manufacturing process,” explains Gal Vered. “These substances reach marine environments through plastic waste and wastewater. Some of them are known to activate or suppress hormonal processes and can therefore disrupt biological systems. However, their effects on organisms in coral reefs have hardly been studied.”

“The structure of the coral reef population depends on the success of the reproduction, development and settlement of corals and other reef organisms. Interference with their hormonal systems may affect the chances of success of these processes, and an uneven effect on the different species may lead to a change in the community’s structure and damage to the entire system.”

The researchers conducted a series of exposure experiments in which the effects of the plastic additives were tested at environmentally relevant concentrations in seawater, and at higher laboratory concentrations. The parameters measured were fertilization, larvae development, larvae survival, and larvae settlement and metamorphoses.

The environmentally relevant concentration of 4-nonylphenol was found to inhibit larvae settlement in the soft coral, while a high concentration of the same compound damaged the fertilization, development, and settlement of all the studied organisms. The higher laboratory concentration of one of the studied phthalate chemicals damaged the settlement only of the stony coral larvae, and not of the other organisms’ reproductive products. These findings add to the accumulating evidence that plastic pollution has a selective effect on different species.

According to Prof. Shenkar, their findings “demonstrate plastic additives’ negative and selective effects on the development and reproduction of coral reef organisms. The environmentally relevant concentrations used in our experiments were concentrations found in seawater; alarmingly, some had deleterious effects on organisms’ reproduction. Nevertheless, concentration within organisms’ tissues may reach higher levels as these compounds can potentially bioaccumulate.”

“To better understand the impact of plastic additives on this endangered ecosystem, we suggest developing better methods for measuring the actual concentrations within the tissues of the organisms to produce relevant risk assessments.”

“Most of the coral reefs in the world are found in developing countries where the human population is expanding rapidly, and waste management is lacking. Steps towards preventing plastic waste from reaching the environment include proper local waste management that reduces transportation of waste, and sustainable consumption of products regulated for additives.” Gal Vered

The Importance of Proper Waste Management

“Climate change, ocean acidification, and ongoing anthropogenic stressors place coral reefs at existential risk,” says Gal Vered. Furthermore, she notes that, “most of the coral reefs in the world are found in developing countries where the human population is expanding rapidly, and waste management is lacking. Steps towards preventing plastic waste from reaching the environment include proper local waste management that reduces transportation of waste, and sustainable consumption of products regulated for additives.”

“We emphasize the importance of proper waste management that will reduce the presence of plastic waste from reaching the marine environment, as well as the need for methods to measure the concentration of chemicals inside the bodies of organisms, in order to assess the possible risk to their reproductive and developmental processes,” the researchers conclude.

Featured image: Prof. Noa Shenkar (photo: Hadas Zion)

TAU Students Continue to Work on Solving the Water Crisis in Northern Tanzania

Written by AUFTAU on 6 December 2022. Posted in Newsroom.

The delegation “Africa Group, Engineers Without Borders Israel – Tel Aviv” went to Tanzania during the country’s worst droughts in history

Tel Aviv University students from The Iby and Aladar Fleischman Faculty of Engineering and the Raymond & Beverly Sackler Faculty of Exact Sciences recently returned from the Babati district in northern Tanzania, where they worked to supply safe drinking water to the local rural population. The students are part of a team of 20 volunteers from various fields and degree levels, called “Africa Group, Engineers Without Borders Israel – Tel Aviv”.

The solution TAU students bring to Tanzania’s water shortage problem is simple and sustainable: through hefty use of the roofs of the regional schools, water can be stored in low-cost rainwater harvesting containers to meet the needs of the children throughout the dry season. The team uses several simple filters and chlorine tablets for storage.

Throughout the year, when TAU volunteers are in Israel and busy with their studies, they still find time to manage all the different aspects of the project, including its fundraising and marketing needs as well as the systems’ construction and implementation. This time around, the students were in Tanzania while the country experienced a severe drought, which resulted in a water crisis and severe hunger.

“During the expedition, we preserved and upgraded our water systems, which at this point provide water to 5,000 children in six schools. We also conducted several pilots for water purification systems; cultivated relationships with organizations that operate in the Babati district; and delivered an extensive educational program on water and sanitation issues together with our local partners. We also visited the area’s new water laboratory (together with the local water authorities). The new lab will be carrying out water tests for us, including in new areas where we are looking to operate in,” say delegation members Aviv Avinoam, Yaeli Benovich, Dan Komiserchick, Sharon Berkovich and Offir Inbar.

Children who get to drink clean water and participate in an extensive educational program on water and sanitation issues

A New Meteorological Station and Empowering School Management

According to Dan Komiserchick, more accurate meteorological data is needed in the Babati district. The team, therefore, together with the local community, installed the first automatic meteorological station in the region, which will be helpful for the planning of future water systems. The station measures parameters such as rain, wind, humidity, and temperature, and the information gathered is transmitted to the water authorities and local farmers and organizations.

One of the highlights of the delegation was organizing a first-of-its-kind executive seminar for all school principals in Babati. “Investing time and resources in training and empowering school principals is critical for the success of the project, as the school principals are very involved in all aspects of the operation of the water purification systems,” explains Aviv Avinoam. “The main topics discussed were maintenance of the systems; insights and suggestions for improvements; educating the students about water safety and training the teachers. The discussions were very enlightening and productive, and it was decided (in agreement with the regional director of education) that the seminar will be held on an annual basis going forward.”

“We also expanded the existing educational program by collaborating with local organizations and creating instructive content on topics like ‘How is rain created?’, ‘Seasons of the year’, ‘How to build water systems’, ‘What pollutants are present in water?’ and more.”

Principals’ Seminar, October 2022

No Room for White Elephants

The team is also conducting a comprehensive academic study to examine the impact of the water systems on the local communities throughout the years, in terms of health, nutrition, entrepreneurship, and more.

The research is led by Yaeli Benovich, who is writing a thesis on the subject with the guidance of Prof. Dror Avisar, Head of the Water Research Center at Tel Aviv University, and Dr. Shira Bookchin from the Hebrew University of Jerusalem, who researches interdisciplinary aspects of sustainability in the developing world.

As part of the research, hundreds of students and educators answered questionnaires aiming to ensure that the activities of Engineers Without Borders are not causing any harm, and making sure that the water project does, in fact, benefit the community. The research adds a professional and academic dimension to the ongoing project and examines the impact of the systems in a broad perspective.

“Visiting the schools and building the water purification systems is only half of the job,” emphasizes Yaeli Benovich. “A lot of projects initiated in Africa quickly turn into so-called ‘white elephants.’ Typically, some foreign organization arrives, pours some money out and leaves the country. Shortly thereafter, the project is abandoned and terminated. We seek to avoid such a situation, by involving the local authorities and the communities as part of the planning and construction of the systems already from an early stage. We are very clear from the start that the local community is responsible for the project.”

Over the years, the Engineers Without Borders delegations have conducted dozens of meetings with the local authorities, including village leaders, heads of the districts and members of parliament. Additionally, they’ve cultivated a close relationship with the local water authorities.

“We signed a contract this year, a memorandum of understanding (MOU), which clearly outlines the role each party has for the success of the project. This contract guides our cooperation with the local representatives,” explains Yael. “The document lists all the responsibilities of our team, as well as those of the local authorities and community – before, during and following the construction of any water purification system. Introducing these written agreements has had a very positive impacted on the contributions by the local authorities and community. There’s no doubt that this is the right way to work. It is a necessary step that will help the community to maintain the project over the years.”

Members of the delegation during a tour of the new water laboratory of Babati district

Offir Inbar shares that in this type of projects, the team’s presence on the ground is critical: “It is only when you physically present and meet with people face to face that you fully understand the situation, the people involved, the challenges at play and in what direction one should be heading.”

“It is hard to bridge various gaps over Zoom conversations or messages. Close relationships are formed by sitting down and talking together at eye level. When you sit down and talk everything seems much simpler – opportunities emerge, you meet with organizations and key people who may lead you to form new connections. It is the only way to fully grasp the challenges facing the local community. Sometimes the challenges on ground are different from what we imagine from afar.”

Close relationships are formed by sitting down and talking together at eye level. An educational activity with school children on the importance of hygiene

Help Ensure the Supply of Water to an Additional 1,000 Children

The drought that hit Africa during the past nine months has emphasized the importance of creating a variety of water solutions. “On our next expedition to Tanzania, planned for April 2023, we will install two new water purification systems to provide clean water to a thousand more children,” says Sharon Berkovich.

“One of the systems will be based on rainwater and the other on the use of filters. The filter system will provide a solution for areas where groundwater or surface water sources exist, but where these are contaminated by bacteria that harm the health of the local community.”

The project is funded mainly by donations from Tel Aviv University, private companies and individual businessmen, philanthropic foundations, and the Embassy of Israel in Kenya. A significant fundraising operation is currently taking place for the upcoming expeditions.

Featured image: Local women collecting water from a polluted water source, drying up in Tanzania

Will COP27 Change the World Order?

Written by AUFTAU on 27 November 2022. Posted in Newsroom.

Our researchers went to Egypt for the 2022 United Nations Climate Change Conference and returned with new insights.

The annual international climate conference held on November 6-20 was attended by world leaders, climate researchers and key officials from all over the world. On the agenda for this year’s summit was the implementation of decisions made at last year’s event, including the design of a global emissions trading program and provision of “loss and damage” funding to vulnerable countries hit hard by the climate crisis. Tel Aviv University researchers participated in several events held at the Israel Pavilion. They presented their groundbreaking research in various fields, aiming to provide practical solutions to the crisis facing our world.

We asked them to share their contributions and takeaways from the event.

“The enthusiasm for outer space is so great that we forget that by launching many satellites, up to hundreds every year, we pollute space and the effect can be fatal in the future.” Prof. Eyal Ben-Dor

Monitoring Climate Change from Space

Prof. Eyal Ben-Dor from the Department of Geography at the Porter School of the Environment and Earth Sciences is a world leading expert in hyperspectral (remote) sensing, a method of imaging the earth’s surface. He participated in a session on how space technologies can contribute to climate action. In the session, organized by the Israel Space Agency and Ministry of Foreign Affairs, Ben-Dor demonstrated innovative applications such as a quantitative monitoring of methane emissions; quantitative assessment of soil erosions following extreme rainfall; and the assessment of vegetation and risk of forest fires given extreme temperature increase.

Ben-Dor gives more details: “Dust constitutes a major problem in several respects: air pollution and breathing problems; migration of dust and with it, bacteria; its lowering of the intensity of radiation; its effect on plants (reducing their photosynthesis), and more. In addition, weather changes impact the risk of forest fires, so it is necessary to monitor this potential to prepare for fires long before they occur. We participate in projects run by foreign space agencies such as NASA [America’s civil space program] and ESA [European Space Agency], in order to monitor atmospheric dust from soil undergoing climatic decay, as well as changes in the organic carbon content in the world’s soils, which is an important component of the global balance of atmospheric carbon.”

His conclusions from the summit? That space can be used to monitor climate change and the phenomena that occur as a result, but with limited liability.

“The enthusiasm for outer space is so great that we forget that by launching many satellites, up to hundreds every year, we pollute space and the effect can be fatal in the future,” he warns. “Space gets filled up with human waste, and humanity must take into account not only the pollution of the earth’s surface, but also of space. Therefore, there should be regulation for planned launches, a sort of ‘launch treaty’ agreed upon by all countries, and priority should be given to launching satellites with a large capacity instead of a large number of satellites with little (but complementary) capacity.”

Ben-Dor returned from the conference with mixed feelings. “The event,” he says, “was good for ‘letting off steam’ between scientists and getting an idea of what is being done in tangential or other environmental fields. New collaborations were created, but it happened at the individual level and not in an organized way. The event was, in my opinion, one big political show of heads of state.”

Monitoring the Earth’s climate from space. Prof. Eyal Ben-Dor

“I was very hopeful that together we will be able to reach a solution and stop global warming. Some will say that this is a naive position, but if we don’t believe there’s a chance to succeed, then what’s the point of participating?” Meital Peleg Mizrahi

“Shocking and Unsettling”

Meital Peleg Mizrahi, is a PhD candidate from TAU’s Department of Public Policy at the Gershon H. Gordon Faculty of Social Sciences and a researcher of consumerism, sustainable fashion and environmental justice. She also presented at the conference, discussing a path to promote green employment and a just transition to a low-carbon economy.

“To be honest, participating at the climate conference was shocking and unsettling,” shares Peleg Mizrahi. “I arrived skeptical, but at the same time I was very hopeful that together we will be able to reach a solution and stop global warming. Some will say that this is a naive position, but if we don’t believe there’s a chance to succeed, then what’s the point of participating?”

According to her, the conference played out more like a business-academic conference than humanity’s greatest effort to fight the climate crisis. As a result, hardly any concrete achievements were made. “This is a very depressing situation, which puts a lot of personal responsibility on us, as researchers and as members of the public.”

“My main conclusion from Sharm El-Sheikh is that the solution won’t come from the governments of the world. The responsibility lies with us.”

Taking responsibility and promoting sustainable consumerism. Meital Peleg Mizrahi

“If we all act responsibly, we can change this world for the better.” Prof. Hadas Mamane

“We Can Change This World for the Better”

Prof. Hadas Mamane, Head of the Environmental Engineering Program at the Iby and Aladar Fleischman Faculty of Engineering, presented on the SoLED project, which aims to make safe drinking water available all over the world. The project offers a groundbreaking off-grid water disinfection device, designed for infrastructure-limited areas such as developing countries and deserts. It is designed to provide maximum disinfection at a low cost, and minimal human intervention is required for installment and operations purposes.

“At the conference, I had the opportunity to meet very interesting people, and listen to discussions that are not standard in terms of professional conferences,” says Mamane. “These included discussions on the climate crisis and women; how students can share their research through media; and the effects of the climate on environmental conflicts between Israel and the Palestinian Authority and between Israel and Jordan.”

“Although I have criticisms – a lot has already been said about ‘greenwashing’ [a critical term that describes the creation of an environmentally conscious public image to supposedly conceal harmful actions] in the context of Coca Cola as supporting sponsor to COP27 – I remain optimistic and think that if we all act responsibly, we can change this world for the better.”

Featured image: Israel’s pavilion at the COP27 conference. From left: Prof. Marcelo Sternberg; Prof. Hadas Mamane; Israel’s Minister of Environmental Protection Tamar Zandberg and Prof. Colin Price

Mobilizing for Efficient Climate Action

Written by AUFTAU on 24 November 2022. Posted in Newsroom.