Biology

What a relief! Microbes transform plastic waste into paracetamol

By ScientifiCult 23 June 2025

What a relief! Microbes transform plastic waste into paracetamol

Paracetamol production could be revolutionised by the discovery that a common bacterium can turn everyday plastic waste into the painkiller, a study reveals.

The new method leaves virtually no carbon emissions and is more sustainable than the current production of the medicine, researchers say.

Paracetamol is traditionally made from dwindling supplies of fossil fuels including crude oil.

Thousands of tons of fossil fuels are used annually to power the factories that produce the painkiller, alongside other medicines and chemicals – making a significant contribution to climate change, experts say.

The breakthrough addresses the urgent need to recycle a widely used plastic known as polyethylene terephthalate (PET), which ultimately ends up in landfill or polluting oceans.

The strong, lightweight plastic is used for water bottles and food packaging, and creates more than 350 million tons of waste annually, causing serious environmental damage worldwide.

PET recycling is possible, but existing processes create products that continue to contribute to plastic pollution worldwide, researchers say.

plastic into paracetamol: A PhD student checks the growth of a culture of Escherichia coli in the Wallace Lab. Photo Credits: University of Edinburgh. — A PhD student checks the growth of a culture of Escherichia coli in the Wallace Lab. Photo Credits: University of Edinburgh.

A team of scientists from the University of Edinburgh’s Wallace Lab used genetically reprogrammed E. coli, a harmless bacterium, to transform a molecule derived from PET known as terephthalic acid into the active ingredient of paracetamol.

Researchers used a fermentation process, similar to the one used in brewing beer, to accelerate the conversion from industrial PET waste into paracetamol in less than 24 hours.

The new technique was carried out at room temperature and created virtually no carbon emissions, proving that paracetamol can be produced sustainably.

Further development is needed before it can be produced at commercial levels, the team says.

Some 90 per cent of the product made from reacting terephthalic acid with genetically reprogrammed E. coli was paracetamol.

The University of Edinburgh is a world-leader in engineering biology, which uses engineering principles to harness biological processes to create new products and services. The University hosts the largest and most comprehensive group of researchers in the country.

Experts say this new approach demonstrates how traditional chemistry can work with engineering biology to create living microbial factories capable of producing sustainable chemicals while also reducing waste, greenhouse gas emissions and reliance on fossil fuels.

The research, published in Nature Chemistry, was funded by an EPSRC CASE award and biopharmaceutical company AstraZeneca, supported by Edinburgh Innovations (EI), the University’s commercialisation service.

Professor Stephen Wallace, lead author, UKRI Future Leaders Fellow and Chair of Chemical Biotechnology, School of Biological Sciences, University of Edinburgh, said:

“This work demonstrates that PET plastic isn’t just waste or a material destined to become more plastic – it can be transformed by microorganisms into valuable new products, including those with potential for treating disease.”

Professor Stephen Wallace. Photo Credits: Edinburgh Innovations and Maverick Photography

Ian Hatch, Head of Consultancy at EI, said: “We are bringing in exceptional companies like AstraZeneca to work with Stephen and others at the University to translate these cutting-edge discoveries into world-changing innovations.

“Engineering biology offers immense potential to disrupt our reliance on fossil fuels, build a circular economy and create sustainable chemicals and materials, and we would invite potential collaborators to get in touch.”

Bibliographic information:

Johnson, N.W., Valenzuela-Ortega, M., Thorpe, T.W. et al., A biocompatible Lossen rearrangement in Escherichia coli, Nat. Chem. (2025), DOI: https://doi.org/10.1038/s41557-025-01845-5

Press release from the University of Edinburgh

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Biology

Massive marimo algae balls at risk from deadly winter sunburn

By ScientifiCult 23 December 2022

Massive marimo algae balls at risk from deadly winter sunburn

Reduced lake-ice cover due to climate change may further decline of endangered species

Climate change could overexpose rare underwater “marimo” algae balls to sunlight, killing them off according to a new study at the University of Tokyo. Marimo are living fluffy balls of green algae. The world’s largest marimo can be found in Lake Akan in Hokkaido, Japan’s northern main island. Here they are sheltered from too much winter sunlight by a thick layer of ice and snow, but the ice is thinning due to global warming. Researchers found that the algae could survive bright light for up to four hours and would recover if then placed under a moderate light for 30 minutes. However, the algae died when exposed to bright light for six hours or more. The team hopes this discovery will highlight the threat of climate change to this endangered species and the urgent need to protect their habitat.

Some people have pet cats, others pet rocks, but how about pet algae? Marimo are fluffy, squishy green balls of underwater algae which have become popular with tourists, nature enthusiasts and aquarium owners. They range in size from about a pea to a basketball, and form naturally when floating strands of the algae Aegagropila linnaei are bundled together through the gentle rolling motion of lake water. They are only found in a few countries and the largest marimo, found in Lake Akan, can grow up to 30 centimeters in diameter. In Japan, they are so popular that they have their own annual festival, merchandise and even a mascot. However, marimo are an endangered species and globally their numbers are generally in decline.

Temperatures underwater are kept relatively stable and warm at around 1-4 degrees Celsius, thanks to the blanket of ice and snow. Above ground, however, they vary from minus 18 degrees to 1 degree Celsius. Credits: copyright 2022 Asami Fujita

Marimo rely on nutrients and photosynthesis to survive. Their decline is usually attributed to human intervention altering or polluting the freshwater lakes in which they live. However, there has not been much research into the effect of changing access to sunlight.

“We know that marimo can survive bright sunlight in warm summer waters, but the photosynthetic properties in marimo at low winter temperatures have not been studied, so we were fascinated by this point,” said Project Assistant Professor Masaru Kono from the Graduate School of Science at the University of Tokyo. “We wanted to find out whether Marimo could tolerate it and how they respond to a low-temperature, high light-intensity environment.”

Kono and team visited Lake Akan’s Churui Bay in winter to measure the temperature and light intensity underwater, both with and without ice cover. First, they bored a small hole in the ice 80 meters offshore and then carved a large 2.5 meter-by-2.5 meter square to take readings from. They also carefully collected several marimo balls about the size of a shot put (10-15 cm) by hand. Back in Tokyo, the team recreated the environmental conditions using trays of ice made with an icemaker and white LED lamps. Algae strands were removed from the marimo balls and tested for their normal photosynthetic ability. They were then placed in containers in the ice under the artificial light, which was adjusted to shine at different intensities for different periods of time.

“We demonstrated a new finding that damaged cells in marimo can repair themselves even after exposure to simulated strong daylight for up to four hours at cold temperatures (2-4 degrees Celsius), when followed by moderate light exposure for just 30 minutes. This moderate light had a restorative effect which did not occur in the dark. However, when exposed to strong daylight for six hours or more, certain cells involved in photosynthesis were damaged and the algae died, even after being treated with moderate light,” explained Kono. “These results suggest that photoinhibition (the inability to photosynthesize due to cell damage) would be a serious threat to marimo in Lake Akan, which receives more than 10 hours of sunlight a day in winter, if global warming proceeds and ice cover recedes.”

Next, the team want to find out what would happen to whole marimo balls and whether the outcome would be the same as with the smaller threads.

“In the present study, we used dissected filamentous cells, so we did not consider the effects of the structure of the spherical marimo and how it might protect against exposure to bright light. However, if damage to the surface cells increases under longer exposure to the direct sunlight, in an extreme case, this may affect the maintenance of their round bodies and lead to the disappearance of giant marimo. So, we need to constantly monitor the conditions at Lake Akan in the future” said Kono.

Kono hopes this research will help both local and national governments to understand the urgent need to protect Japan’s unique marimo and their habitat.

“We also hope this will be an opportunity for all people to think seriously about the effects of global warming,” he said.

Too much sun in cold temperatures cannot be processed and instead causes harmful, reactive chemicals to form. This damages the marimo’s ability to photosynthesize and repair itself. Credits: Copyright 2022 Akina Obara

#####

Paper Title:

Akina Obara, Mari Ogawa, Yoichi Oyama, Yoshihiro Suzuki, Masaru Kono. Effects of high irradiance and low water-temperature on photoinhibition and repair of photosystems in Marimo (Aegagropila linnaei) in Lake Akan, Japan. Int. J. Mol. Sci. 2023, 24(1), 60; https://doi.org/10.3390/ijms24010060

Press release from the University of Tokyo.

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Genetics

Discovery of world’s oldest DNA breaks record by one million years

By ScientifiCult 7 December 2022

A new chapter in the history of evolution

Discovery of world’s oldest DNA breaks record by one million years

Two-million-year-old DNA has been identified for the first time opening a new chapter in the history of evolution.

Microscopic fragments of environmental DNA were found in Ice Age sediment in northern Greenland. The fragments are one million years older than the previous record for DNA sampled from a Siberian mammoth bone.

The ancient DNA has been used to map a two-million-year-old ecosystem which weathered extreme climate change. The results could help predict the long-term environmental toll of today’s global warming.

The discovery was made by a team of scientists led by Professor Eske Willerslev and Professor Kurt Kjær. Professor Willerslev is a Fellow of St John’s College, University of Cambridge and Director of the Lundbeck Foundation GeoGenetics Centre at the University of Copenhagen where Professor Kjær, a geology expert, is also based.

The results of the 41 usable samples found hidden in clay and quartz are published today in Nature.

“A new chapter spanning one million extra years of history has finally been opened and for the first time we can look directly at the DNA of a past ecosystem that far back in time,” says Willerslev.

“DNA can degrade quickly but we’ve shown that under the right circumstances, we can now go back further in time than anyone could have dared imagine.”

“The ancient DNA samples were found buried deep in sediment that had built-up over 20,000 years,” says Kjær. “The sediment was eventually preserved in ice or permafrost and, crucially, not disturbed by humans for two million years.”

Close-up of organic material in the coastal deposits. The organic layers show traces of the rich plant flora and insect fauna that lived two million years ago in Kap København in North Greenland. Credits: Professor Kurt H. Kjær

The incomplete samples, a few millionths of a millimetre long, were taken from the København Formation, a sediment deposit almost 100 metres thick tucked in the mouth of a fjord in the Arctic Ocean in Greenland’s northernmost point. The climate in Greenland at the time varied between Arctic and temperate and was between 10-17C warmer than Greenland is today. The sediment built up metre by metre in a shallow bay.

Evidence of animals, plants and microorganisms including reindeer, hares, lemmings, birch and poplar trees were discovered. Researchers even found that Mastodon, an Ice Age mammal, roamed as far as Greenland before later becoming extinct. Previously it was thought the range of the elephant-like animals did not extend as far as Greenland from its known origins of North and Central America.

Detective work by 40 researchers from Denmark, the UK, France, Sweden, Norway, the USA and Germany, unlocked the secrets of the fragments of DNA. The process was painstaking – first they needed to establish whether there was DNA hidden in the clay and quartz, and if there was, could they successfully detach the DNA from the sediment to examine it? The answer, eventually, was yes. The researchers compared every single DNA fragment with extensive libraries of DNA collected from present-day animals, plants and microorganisms. A picture began to emerge of the DNA from trees, bushes, birds, animals and microorganisms.

A two million- year-old trunk from a larch tree still stuck in the permafrost within the coastal deposits. The tree was carried to the sea by the rivers that eroded the former forested landscape. Credits: Professor Svend Funder

Some of the DNA fragments were easy to classify as predecessors to present-day species, others could only be linked at genus level, and some originated from species impossible to place in the DNA libraries of animals, plants and microorganisms still living in the 21st century.

The two-million-year-old samples also help academics build a picture of a previously unknown stage in the evolution of the DNA of a range of species still in existence today.

“Expeditions are expensive and many of the samples were taken back in 2006 when the team were in Greenland for another project, they have been stored ever since,” says Kjær.

“It wasn’t until a new generation of DNA extraction and sequencing equipment was developed that we’ve been able to locate and identify extremely small and damaged fragments of DNA in the sediment samples. It meant we were finally able to map a two-million-year-old ecosystem.”

“The Kap København ecosystem, which has no present-day equivalent, existed at considerably higher temperatures than we have today – and because, on the face of it, the climate seems to have been similar to the climate we expect on our planet in the future due to global warming,” says co-first author Assistant Professor Mikkel Pedersen of the Lundbeck Foundation GeoGenetics Centre.

“One of the key factors here is to what degree species will be able to adapt to the change in conditions arising from a significant increase in temperature. The data suggests that more species can evolve and adapt to wildly varying temperatures than previously thought. But, crucially, these results show they need time to do this. The speed of today’s global warming means organisms and species do not have that time so the climate emergency remains a huge threat to biodiversity and the world – extinction is on the horizon for some species including plants and trees.”

While reviewing the ancient DNA from the Kap København Formation, the researchers also found DNA from a wide range of microorganisms, including bacteria and fungi, which they are continuing to map. A detailed description of how the interaction – between animals, plants and single-cell organisms – within the former ecosystem at Greenland’s northernmost point worked biologically will be presented in a future research paper.

It is now hoped that some of the ‘tricks’ of the two-million-year-old plant DNA discovered may be used to help make some endangered species more resistant to a warming climate.

“It is possible that genetic engineering could mimic the strategy developed by plants and trees two million years ago to survive in a climate characterised by rising temperatures and prevent the extinction of some species, plants and trees,” says Kjær. “This is one of the reasons this scientific advance is so significant because it could reveal how to attempt to counteract the devastating impact of global warming.”

The findings from the Kap København Formation in Greenland have opened up a whole new period in DNA detection.

“DNA generally survives best in cold, dry conditions such as those that prevailed during most of the period since the material was deposited at Kap København,” says Willerslev. “Now that we have successfully extracted ancient DNA from clay and quartz, it may be possible that clay may have preserved ancient DNA in warm, humid environments in sites found in Africa.

“If we can begin to explore ancient DNA in clay grains from Africa, we may be able to gather ground-breaking information about the origin of many different species – perhaps even new knowledge about the first humans and their ancestors – the possibilities are endless.”

Bibliographic information:

A 2-million-year-old ecosystem in Greenland uncovered by environmental DNA, Nature (7-Dec-2022), DOI: 10.1038/s41586-022-05453-y

Press release from the University of Cambridge on the discovery of world’s oldest DNA.

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Biology

Global warming spawned the age of reptiles

By ScientifiCult 19 August 2022

Global warming spawned the age of reptiles

Harvard researchers find rapid evolution of reptiles was triggered by nearly 60 million years of global warming and climate change

Artistic reconstruction of the reptile adaptive radiation in a terrestrial ecosystem during the warmest period in Earth’s history. Image depicts a massive, big-headed, carnivorous erythrosuchid (close relative to crocodiles and dinosaurs) and a tiny gliding reptile at about 240 million years ago. The erythrosuchid is chasing the gliding reptile and it is propelling itself using a fossilized skull of the extinct Dimetrodon (early mammalian ancestor) in a hot and dry river valley. Credits: Image created by Henry Sharpe

Studying climate change-induced mass extinctions in the deep geological past allows researchers to explore the impact of environmental crises on organismal evolution. One principal example is the Permian-Triassic climatic crises, a series of climatic shifts driven by global warming that occurred between the Middle Permian (265 million years ago) and Middle Triassic (230 million years ago). These climatic shifts caused two of the largest mass extinctions in the history of life at the end of the Permian, the first at 261myo and the other at 252myo, the latter eliminating 86% of all animal species worldwide.

The end-Permian extinctions are important not only because of their magnitude, but also because they mark the onset of a new era in the history of the planet when reptiles became the dominant group of vertebrate animals living on land. During the Permian, vertebrate faunas on land were dominated by synapsids, the ancestors of mammals. After the Permian extinctions, in the Triassic Period (252-200 million years ago), reptiles evolved at rapid rates, creating an explosion of reptile diversity. This expansion was key to the construction of modern ecosystems and many extinct ecosystems. These rapid rates of evolution and diversification were believed by most paleontologists to be due to the extinction of competitors allowing reptiles to take over new habitats and food resources that several synapsid groups had dominated before their extinction.

Global warming spawned the age of reptiles — Evolutionary response from reptiles to global warming and fast climatic changes. Rates of evolution (adaptive anatomical changes) in reptiles start increasing early in the Permian (at about 294 million years ago), which also marks the onset of the longest period of successive fast climatic shifts in the geological record. From 261 until 235 million years ago, increased global warming from massive volcanic eruption contributed to further climate change and led to the hottest period in Earth’s history. This resulted in two mass extinctions and the demise of reptile competitors on land (mammalian ancestors). The most intensive period of global warming coincided with the fastest rates of evolution in reptiles, marking the diversification of reptile body plans and the origin of modern reptile groups. Credits: Figure by Tiago Simões

However, in a new study in Sciences Advances researchers in the Department of Organismic and Evolutionary Biology and the Museum of Comparative Zoology at Harvard University and collaborators reveal the rapid evolution and radiation of reptiles began much earlier, before the end of the Permian, in connection to the steadily increasing global temperatures through a long series of climatic changes that spanned almost 60 million years in the geological record.

“We found that these periods of rapid evolution of reptiles were intimately connected to increasing temperatures. Some groups changed really fast and some less fast, but nearly all reptiles were evolving much faster than they ever had before,” said lead author postdoctoral fellow Tiago R Simões.

Previous studies on the impacts of these changes have often neglected terrestrial vertebrates due to limited data availability, focusing mostly on the response from marine animals

In this study, Simões and senior author Professor Stephanie E. Pierce (both at Harvard) worked alongside collaborators Professor Michael Caldwell (University of Alberta, Canada) and Dr. Christian Kammerer (North Carolina Museum of Natural Sciences) to examine early amniotes, which represent the forerunners of all modern mammals, reptiles, birds, and their closest extinct relatives, at the initial phase of their evolution. At this point in time the first groups of reptiles and mammal ancestors were splitting from each other and evolving along their own separate evolutionary paths.

“Reptiles represent an ideal and rare terrestrial system to study this question as they have a relatively good fossil record and survived a series of climatic crises including the ones leading up to the largest extinction in the history of complex life, the Permian-Triassic mass extinction,” said Simões.

Reptiles were relatively rare during the Permian compared to mammalian ancestors. However, things took a major shift during the Triassic when reptiles underwent a massive explosion in the number of species and morphological variety. This lead to the appearance of most of the major living groups of reptiles (crocodiles, lizards, turtles) and several groups that are now entirely extinct.

The researchers created a dataset based on extensive first-hand data collection of more than 1,000 fossil specimens from 125 species of reptiles, synapsids, and their closest relatives during approximately 140 million years before and after the Permian-Triassic extinction. They then analyzed the data to detect when these species first originated and how fast they were evolving using state-of-the-art analytical techniques such as Bayesian evolutionary analysis, which is also used to understand the evolution of viruses such as SARS-COVID 19. The researchers then combined the new dataset with global temperature data spanning several million years in the geological record to provide a broad overview of the animals’ major adaptive response towards climatic shifts.

“Our results reveal that periods of fast climatic shifts and global warming are associated with exceptionally high rates of anatomical change in most groups of reptiles as they adapted to new environmental conditions,” said Pierce, “and this process started long before the Permian-Triassic extinction, since at least 270 million years ago, indicating that the diversification of reptile body plans was not triggered by the P-T extinction event as previously thought, but in fact started tens of million years before that.”

“One reptile lineage, the lepidosaurs, which gave rise to the first lizards and tuataras, veered in the opposite direction of most reptile groups and underwent a phase of very slow rates of change to their overall anatomy,” said Simões, “essentially, their body plans were constrained by natural selection, instead of going rogue and radically changing like most other reptiles at the time.” The researchers suggest this is due to pre-adaptations on their body size to better cope with high temperatures.

“The physiology of organisms is really dependent on their body size,” said Simões, “small-bodied reptiles can better exchange heat with their surrounding environment. The first lizards and tuataras were much smaller than other groups of reptiles, not that different from their modern relatives, and so they were better adapted to cope with drastic temperature changes. The much larger ancestors of crocodiles, turtles, and dinosaurs could not lose heat as easily and had to quickly change their bodies in order to adapt to the new environmental conditions.”

Simões, Pierce, and collaborators also mapped out how body size changed across geographical regions during this timeframe. They revealed that climatic pressures on body size were so high there was a maximum body size for reptiles to survive in tropical regions during the lethally hot periods of this time.

“Large-sized reptiles basically took two routes to deal with these climate shifts,” said Pierce, “they either migrated closer to temperate regions or invaded the aquatic world where they didn’t need to worry about overheating because water can absorb heat and maintain its temperature much better than air.”

“This strong association between rising temperatures in the geological past and a biological response by dramatically different groups of reptiles suggests climate change was a key factor in explaining the origin and the explosion of new reptile body plans during the latest Permian and Triassic,” said Simões.

The researchers would like to thank the Museum of Comparative Zoology (MCZ), Harvard University, vertebrate paleontology staff and the curators across 50+ natural history collections worldwide for their help with specimen access. Funding was provided by: Alexander Agassiz Postdoctoral Fellowship, MCZ; National Sciences and Engineering Research Council of Canada (NSERC) postdoctoral fellowship; Grant KA 4133/1-1 from the Deutsche Forschungsgemeinschaft; NSERC Discovery Grant #23458 and NSERC Accelerator Grant; Faculty of Science, Chairs Research Allowance, University of Alberta; Lemann Brazil Research Fund; Funds made available through Harvard University.

Successive climate crises in the deep past drove the early evolution and radiation of reptiles, Science Advances (19-Aug-2022), DOI: 10.1126/sciadv.abq1898

Press release from Harvard University, Department of Organismic and Evolutionary Biology.

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Environmental Science

Heat stress: the climate is putting European forests under sustained pressure

By ScientifiCult 19 July 2020

Heat stress: the climate is putting European forests under sustained pressure

No year since weather records began was as hot and dry as 2018. A first comprehensive analysis of the consequences of this drought and heat event shows that central European forests sustained long-term damage. Even tree species considered drought-resistant, such as beech, pine and silver fir, suffered. The international study was directed by the University of Basel, which is conducting a forest experiment unique in Europe.

In a forest near Basel researchers study the effects of climate change on the most important and sensitive part of the trees – the canopy. A total of 450 trees between 50 and 120 years old grow on the 1.6 hectare research area. Credits: University of Basel

Until now, 2003 has been the driest and hottest year since regular weather records began. That record has now been broken. A comparison of climate data from Germany, Austria and Switzerland shows that 2018 was significantly warmer. The average temperature during the vegetation period was 1.2°C above the 2003 value and as high as 3.3°C above the average of the years from 1961 to 1990.

Part of the analysis, which has now been published, includes measurements taken at the Swiss Canopy Crane II research site in Basel, where extensive physiological investigations were carried out in tree canopies. The goal of these investigations is to better understand how and when trees are affected by a lack of water in order to counter the consequences of climate change through targeted management measures.

When trees die of thirst

Trees lose a lot of water through their surfaces. If the soil also dries out, the tree cannot replace this water, which is shown by the negative suction tension in the wood’s vascular tissue. It’s true that trees can reduce their water consumption, but if the soil water reservoir is used up, it’s ultimately only a matter of time until cell dehydration causes the death of a tree.

Physiological measurements at the Basel research site have shown the researchers that the negative suction tension and water shortage in trees occurred earlier than usual. In particular, this shortage was more severe throughout all of Germany, Austria and Switzerland than ever measured before. Over the course of the summer, severe drought-related stress symptoms therefore appeared in many tree species important to forestry. Leaves wilted, aged and were shed prematurely.

Death of a beech tree in a forest near Basel: during the 2018 heatwave the leaves died prematurely, the following year the tree stopped forming new shoots. Credits: Urs Weber, University of Basel

Spruce, pine and beech most heavily affected

The true extent of the summer heatwave became evident in 2019: many trees no longer formed new shoots – they were partially or wholly dead. Others had survived the stress of the drought and heat of the previous year, but were increasingly vulnerable to bark beetle infestation or fungus. Trees with partially dead canopies, which reduced the ability to recover from the damage, were particularly affected.

“Spruce was most heavily affected. But it was a surprise for us that beech, silver fir and pine were also damaged to this extent,” says lead researcher Professor Ansgar Kahmen. Beech in particular had until then been classified as the “tree of the future”, although its supposed drought resistance has been subject to contentious discussion since the 2003 heatwave.

heat European forests — Death of a beech tree in a forest near Basel: during the 2018 heatwave the leaves died prematurely, the following year the tree stopped foring new shoots. Credits: Urs Weber, University of Basel

Future scenarios to combat heat and drought

According to the latest projections, precipitation in Europe will decline by up to a fifth by 2085, and drought and heat events will become more frequent. Redesigning forests is therefore essential. “Mixed woodland is often propagated,” explains plant ecologist Kahmen, “and it certainly has many ecological and economic advantages. But whether mixed woodland is also more drought-resistant has not yet been clearly proven. We still need to study which tree species are good in which combinations, including from a forestry perspective. That will take a long time.”

Another finding of the study is that it is only possible to record the impacts of extreme climate events on European forests to a limited extent using conventional methods, and thus new analytical approaches are needed.“The damage is obvious. More difficult is precisely quantifying it and drawing the right conclusions for the future,” says Kahmen. Earth observation data from satellites could help track tree mortality on a smaller scale. Spatial patterns that contain important ecological and forestry-related information can be derived from such data: which tree species were heavily impacted, when and at which locations, and which survived without damage? “A system like this already exists in some regions in the US, but central Europe still lacks one.”

Original source

Schuldt, Bernhard & Buras, Allan & Arend, Matthias & Vitasse, Yann & Beierkuhnlein, Carl & Damm, Alexander & Gharun, Mana & Grams, Thorsten & Hauck, Markus & Hajek, Peter & Hartmann, Henrik & Hilbrunner, Erika & Hoch, Günter & Holloway-Phillips, Meisha & Körner, Christian & Larysch, Elena & Luebbe, Torben & Nelson, Daniel & Rammig, Anja & Kahmen, Ansgar.

A first assessment of the impact of the extreme 2018 summer drought on Central European forests.
Basic and Applied Ecology (April 2020); doi: 10.1016/j.baae.2020.04.003

Press release on the heat stress upon European forests from the University of Basel.

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Environmental Science

World can likely capture and store enough carbon dioxide to meet climate targets

By ScientifiCult 3 June 2020

World can likely capture and store enough carbon dioxide to meet climate targets

The world is currently on track to fulfil scenarios on diverting atmospheric CO2 to underground reservoirs, according to a new study by Imperial.

The capture and storage of carbon dioxide (CO₂) underground is one of the key components of the Intergovernmental Panel on Climate Change’s (IPCC) reports keeping global warming to less than 2°C above pre-industrial levels by 2100.

Carbon capture and storage (CCS) would be used alongside other interventions such as renewable energy, energy efficiency, and electrification of the transportation sector.

carbon dioxide storage — Picture by Gerd Altmann

The IPCC used models to create around 1,200 technology scenarios whereby climate change targets are met using a mix of these interventions, most of which require the use of CCS.

Their reports are available here and here.

Now a new analysis from Imperial College London suggests that just 2,700 Gigatonnes (Gt) of carbon dioxide (CO₂) would be sufficient to meet the IPCC’s global warming targets. This is far less than leading estimates by academic and industry groups of what is available, which suggest there is more than 10,000 Gt of CO₂ storage space globally.

It also found that that the current rate of growth in the installed capacity of CCS is on track to meet some of the targets identified in IPCC reports, and that research and commercial efforts should focus on maintaining this growth while identifying enough underground space to store this much CO₂.

The findings are published in Energy & Environmental Science.

Capturing carbon

CCS involves trapping CO₂ at its emission source, such as fossil-fuel power stations, and storing it underground to keep it from entering the atmosphere. Together with other climate change mitigation strategies, CCS could help the world reach the climate change mitigation goals set out by the IPCC.

However, until now the amount of storage needed has not been specifically quantified.

The research team, led by Dr Christopher Zahasky at Imperial’s Department of Earth Science and Engineering, found that worldwide, there has been 8.6 per cent growth in CCS capacity over the past 20 years, putting us on a trajectory to meet many climate change mitigation scenarios that include CCS as part of the mix.

Dr Zahasky, who is now an assistant professor at the University of Wisconsin-Madison but conducted the work at Imperial, said: “Nearly all IPCC pathways to limit warming to 2°C require tens of Gts of CO₂ stored per year by mid-century. However, until now, we didn’t know if these targets were achievable given historic data, or how these targets related to subsurface storage space requirements.

“We found that even the most ambitious scenarios are unlikely to need more than 2,700 Gt of CO₂ storage resource globally, much less than the 10,000 Gt of storage resource that leading reports suggest is possible.?Our study shows that if climate change targets are not met by 2100, it won’t be for a lack of carbon capture and storage space.”

Study co-author Dr Samuel Krevor, also from the Department of Earth Science and Engineering, said: “Rather than focus our attention on looking at how much storage space is available, we decided for the first time to evaluate how much subsurface storage resource is actually needed, and how quickly it must be developed, to meet climate change mitigation targets.”

Speed matters

The study has shown for the first time that the maximum storage space needed is only around 2,700 Gt, but that this amount will grow if CCS deployment is delayed. The researchers worked this out by combining data on the past 20 years of growth in CCS, information on historical rates of growth in energy infrastructure, and models commonly used to monitor the depletion of natural resources.

The researchers say that the rate at which CO₂ is stored is important in its success in climate change mitigation. The faster CO₂ is stored, the less total subsurface storage resource is needed to meet storage targets. This is because it becomes harder to find new reservoirs or make further use of existing reservoirs as they become full.

They found that storing faster and sooner than current deployment might be needed to help governments meet the most ambitious climate change mitigation scenarios identified by the IPCC.

The study also demonstrates how using growth models, a common tool in resource assessment, can help industry and governments to monitor short-term CCS deployment progress and long-term resource requirements.

However, the researchers point out that meeting CCS storage requirements will not be sufficient on its own to meet the IPCC climate change mitigation targets.

Dr Krevor said: “Our analysis shows good news for CCS if we keep up with this trajectory – but there are many other factors in mitigating climate change and its catastrophic effects, like using cleaner energy and transport as well as significantly increasing the efficiency of energy use.”

Funding for this work was provided by ACT ELEGANCY, DETEC (CH), BMWi (DE), RVO (NL), Gassnova (NO), BEIS (UK), Gassco, Equinor and Total, the European Commission under the Horizon 2020 programme, the UK CCS Research Centre and EPSRC.

“Global geologic carbon storage requirements of climate change mitigation scenarios” by Christopher Zahasky and Samuel Krevor, published 21 May 2020 in Energy & Environmental Science.

Press release by Caroline Brogan, from the Imperial College London

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Environmental Science

A rising tide of marine disease? How parasites respond to a warming world

By ScientifiCult 3 June 2020

A rising tide of marine disease? How parasites respond to a warming world

Sea star wasting disease, pictured here, is likely caused by the sea star associated densovirus. Credits: Oregon State Parks

Warming events are increasing in magnitude and severity, threatening many ecosystems worldwide. As the global temperatures continue to climb, it also raises uncertainties as to the relationship, prevalence, and spread of parasites and disease.

A recent study from the University of Washington explores the ways parasitism will respond to climate change, providing researchers new insights into disease transmission. The paper was published in May in Trends in Ecology and Evolution.

The review builds upon previous research by adding nearly two decades worth of new evidence to build a framework showing the parasite–host relationship under climate oscillations. Traditionally, climate related research is done over long time scales, however this unique approach examines how increasingly frequent “pulse warming” events alter parasite transmission.

“Much of what is known about how organisms and ecosystems can respond to climate change has focused on gradual warming,” said lead author Danielle Claar, a postdoctoral researcher at the UW School of Aquatic and Fishery Sciences. “Climate change causes not only gradual warming over time, but also increases the frequency and magnitude of extreme events, like heat waves.”

Claar explains that both gradual warming and pulse warming can and have influenced ecosystems, but do so in different ways. Organisms may be able to adapt and keep pace with the gradual warming, but an acute pulse event can have sudden and profound impacts.

parasites warming — A sea star ravaged by sea star wasting disease. Credits: Alison Leigh Lilly

The 2013-2015 “blob” is one such extreme heat pulse event which has been linked to a massive die-off of sea stars along the Pacific coast of the U.S. and Canada. Many species of sea stars, including the large sunflower sea star, were decimated by a sudden epidemic of wasting disease. Five years later, populations in the region are still struggling to recover. The abnormally warm waters associated with the blob are thought to have favored the spread of the sea star-associated densovirus, the suggested cause of the disease.

The authors compare the prevalence of these marine diseases to a rising tide, an ebbing tide, or a tsunami. Disease transmission can rise or ebb in concert with gradual warming or a series of pulse warming events. However, a severe pulse warming event could result in a tsunami, “initiating either a deluge or drought of disease,” as was observed with sea stars along the Pacific Northwest.

However, not all pulse heat events will cause the same response. What may benefit a particular parasite or host in one system can be detrimental in another. Warming can alter a parasite’s life cycle, limit the range of suitable host species, or even impair the host’s immune response. Some flatworms which target wildlife and humans cannot survive as long in warmer waters, decreasing their window for infecting a host. Another recent UW study shows parasites commonly found in sushi are on the rise with their numbers increasing 283-fold in the past 40 years, though the relationship between heat pulse events and their abundance is not yet clear.

“The relationships between hosts, parasites, and their corresponding communities are complex and depend on many factors, making outcomes difficult to predict,” said Claar, who recommends researchers make predictions on a case-by-case basis for their individual systems.

The authors conclude that rather than a straightforward tidal prediction, they would expect pulse warming to cause “choppy seas with the occasional rogue wave.”

“It is important that we are able to understand and predict how parasitism and disease might respond to climate change, so we can prepare for, and mitigate, potential impacts to human and wildlife health,” said Claar.

The paper’s co-author is Chelsea Wood, a UW assistant professor of aquatic and fishery sciences.

This research was supported by the NOAA Climate and Global Change Postdoctoral Fellowship Program, administered by UCAR’s Cooperative Programs for the Advancement of Earth System Science (CPAESS); the US National Science Foundation; a Sloan Research Fellowship from the Alfred P. Sloan Foundation; a UW Innovation Award from the UW President’s Innovation Imperative; and a UW Royalty Research Fund Award.

Press release by Dan Nicola from the School of Aquatic and Fishery Sciences of the University of Washington.

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Biology

When pollen is in short supply, Bumblebees speed up flowering

By ScientifiCult 28 May 2020

When pollen is in short supply, bumblebees damage plant leaves in a way that accelerates flower production, as an ETH research team headed up by Consuelo De Moraes and Mark Mescher has demonstrated.

Spring has sprung earlier than ever before this year, accompanied by temperatures more typical of early summertime. Many plants were already in full bloom by mid-April, about three to four weeks earlier than normal. These types of seasonal anomalies are becoming increasingly frequent due to climate change, and the resulting uncertainty threatens to disrupt the timing of mutualistic relationships between plants and their insect pollinators.

A research team led by ETH Professors Consuelo De Moraes and Mark Mescher has now discovered that one peculiar bumblebee behaviour may help to overcome such challenges by facilitating coordination between the bees and the plants they pollinate. The group has found that bumblebee workers use their mouth parts to pinch into the leaves of plants that haven’t flowered yet, and that the resulting damage stimulates the production of new flowers that bloom earlier than those on plants that haven’t been given this “nudge”.

Their study has just been published in the journal Science. “Previous work has shown that various kinds of stress can induce plants to flower, but the role of bee-inflicted damage in accelerating flower production was unexpected,” Mescher says.

bumblebees pollen — If bumblebees find too little pollen, they pierce the leaves of non-flowering plants in order to force them to produce flowers more quickly. Credits: Photograph: Hannier Pulido / ETH Zurich

Surprising behaviour from bumblebees

The researchers first noticed the behaviour during other experiments being undertaken by one of the authors, Foteini Pashalidou: pollinators were biting the leaves of test plants in the greenhouse. “On further investigation, we found that others had also observed such behaviours, but no one had explored what the bees were doing to the plants or reported an effect on flower production,” Mescher explains.

Following up on their observations, the ETH researchers devised several new laboratory experiments, and also conducted outdoor studies using commercially available bumblebee colonies – typically sold for the pollination of agricultural crops – and a variety of plant species.

Based on their lab studies, the researchers were able to show that the bumblebees’ propensity to damage leaves has a strong correlation with the amount of pollen they can obtain: Bees damage leaves much more frequently when there is little or no pollen available to them. They also found that damage inflicted on plant leaves had dramatic effects on flowering time in two different plant species. Tomato plants subjected to bumblebee biting flowered up to 30 days earlier than those that hadn’t been targeted, while mustard plants flowered about 14 days earlier when damaged by the bees.

“The bee damage had a dramatic influence on the flowering of the plants – one that has never been described before,” De Moraes says. She also suggests that the developmental stage of the plant when it is bitten by bumblebees may influence the degree to which flowering is accelerated, a factor the investigators plan to explore in future work.

The researchers tried to manually replicate the damage patterns caused by bees to see if they could reproduce the effect on flowering time. But, while this manipulation did lead to somewhat earlier flowering in both plant species, the effect was not nearly as strong as that caused by the bees themselves. This leads De Moraes to suggest that some chemical or other cue may also be involved. “Either that or our manual imitation of the damage wasn’t accurate enough,” she says. Her team is currently trying to identify the precise cues responsible for inducing flowering and characterising the molecular mechanisms involved in the plant response to bee damage.

Phenomenon also observed in the field

The ETH research team was also able to observe the bees’ damaging behaviour under more natural conditions, with doctoral student Harriet Lambert leading follow-up studies on the rooftops of two ETH buildings in central Zurich. In these experiments, the researchers again observed that hungry bumblebees with insufficient pollen supplies frequently damaged the leaves of non-blooming plants. But the damaging behaviour was consistently reduced when the researchers made more flowers available to the bees.

Furthermore, it was not only captive-bred bumblebees from the researchers’ experimental colonies that damaged plant leaves. The investigators also observed wild bees from at least two additional bumblebee species biting the leaves of plants in their experimental plots. Other pollinating insects, such as honeybees, did not exhibit such behaviour, however: they seemed to ignore the non-flowering plants entirely, despite being frequent visitors to nearby patches of flowering plants.

Delicate balance starting to tip

“Bumblebees may have found an effective method of mitigating local shortages of pollen,” De Moraes says. “Our open fields are abuzz with other pollinators, too, which may also benefit from the bumblebees’ efforts.” But it remains to be seen whether this mechanism is sufficient to overcome the challenges of changing climate. Insects and flowering plants have evolved together, sharing a long history that strikes a delicate balance between efflorescence and pollinator development. However, global warming and other anthropogenic environmental changes have the potential to disrupt the timing of these and other ecologically important interactions among species. Such rapid environmental change could result in insects and plants becoming increasingly out of sync in their development, for example. “And that’s something from which both sides stand to lose,” Mescher says.

Reference paper on bumblebees when pollen is in short supply

Paschalidou FG, Lambert H, Peybernes T, Mescher MC, De Moraes CM. Bumble bees damage plant leaves and accelerate flower production when pollen is scarce. Science, published online May 21st 2020. DOI: 10.1126/science.aay0496

Press release from ETH Zürich

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