Wednesday, September 09, 2026

Europe's forests are still standing, but many are losing the ability to recover

New eLTER policy brief calls for forest resilience to become a measurable objective of European policy, underpinned by long-term ecosystem observation

Pensoft Publishers

Long-term observations are what turn resilience from an appealing concept into something we can test and improve - says Giorgio Vacchiano of the University of Milan — image:
Instruments and infrastructure for long-term observation at an eLTER site
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Credit: Evgeni Dimitrov/eLTER

A forest can look intact from the roadside and still have lost much of its capacity to bounce back. That gap between appearance and function is at the centre of a new policy brief published by eLTER, the European research infrastructure for long-term ecosystem, critical zone and socio-ecological research.

Across Europe, the rate at which forests are damaged by drought, storms, wildfire and insect outbreaks has more than doubled over the past three decades, and climate-driven damage already costs several billion euros a year. Compound events, where drought is followed by fire or by pest outbreaks, magnify those losses and slow recovery further.

The brief, Forests at Risk: Measuring and Building Resilience Against Extreme Climate Events, argues that resilience should become an explicit and measurable objective of European forest management and policy rather than an aspiration that is assessed only after damage has occurred.

“Summer 2026 has made the issue tangible: prolonged heat and drought have stressed forests across much of Europe, while by late August wildfires had burned more than 630,000 hectares in the EU, roughly twice the 20-year average for this point in the season. However, resilience is not simply whether a forest is still standing after a disturbance. The question is whether forests can maintain their functions, regenerate and adapt as conditions change. If we do not measure those processes, we cannot manage them,” says Giorgio Vacchiano of the University of Milan, author of the policy brief.

The stakes reach well past timber. Extreme events put biodiversity, rural livelihoods and cultural landscapes at risk, and raise the likelihood of floods and landslides. Europe's forests currently absorb around 360 million tonnes of carbon dioxide a year, but that sink is weakening as stands age, harvesting intensifies and disturbances grow more frequent. Without adaptation, the brief warns, European climate targets become harder to meet.

Looking beyond area and biomass

Forest monitoring and reporting still concentrate largely on how much forest there is and how much biomass it holds. Those figures matter, but they say little about whether a stand can resist a shock, recover afterwards or adjust to a changing climate.

The brief calls instead for a broader set of resilience indicators covering recovery capacity, regeneration, structural and functional diversity, landscape connectivity, and the capacity of species to adapt or shift their range.

Satellite observation can supply early-warning signals before decline becomes visible on the ground. A drop in photosynthetic activity, for instance, can indicate that recovery is slowing and that a stand is approaching a critical threshold. Monitoring also needs to capture compound disturbances, which are becoming more common yet remain poorly represented in conventional assessment systems.

Paired with long-term field observation, scenario-based models can combine three dimensions of risk at once: the climate hazard, the vulnerability of the forest and its adaptive capacity. That allows policymakers and forest managers to test "what-if" futures and target intervention where it is most needed.

Building resilience in practice

The brief sets out management approaches that can strengthen resilience, among them Closer-to-Nature and Climate-Smart Forestry, greater diversity of tree species and forest structures, restoration of hydrological function, and carefully planned assisted migration of suitable species and provenances. Biodiversity is central throughout: complementary species and functions help forests absorb uncertainty while continuing to store carbon, regulate water and support livelihoods.

Five directions for action are recommended:

Mainstream climate-smart planning using resilience indicators and scenario modelling.
Introduce quantitative resilience targets into national forest, climate, adaptation and nature restoration strategies.
Invest in long-term observation and research infrastructures such as eLTER.
Support biodiversity-based and closer-to-nature management through payments for ecosystem services and well-designed nature credits.
Align forest management more closely with natural disturbance regimes to sustain resilience and carbon uptake.

At regional level, the brief points to fire-prevention planning in Tuscany and Lombardy, where climate projections, vegetation dynamics and fire-behaviour models are already used to prioritise areas for intervention.

Why long-term observation is the missing link

Resilience cannot be read off a single measurement or judged only after a disaster. It has to be observed across years and decades.

Through its distributed network of long-term research sites and socio-ecological platforms, eLTER tracks tree growth and mortality, soil moisture, carbon pools and water balance over exactly those timescales. Remote-sensing time series help flag early warnings, while sustained field observation supplies the evidence needed to calibrate models and to test whether management interventions genuinely improve resistance and recovery. Comparable observations from across Europe also make it possible to identify which approaches work, under which conditions and with which trade-offs.

“Long-term observations are what turn resilience from an appealing concept into something we can test and improve. They allow us to see whether recovery is slowing, whether a forest is approaching a threshold, and whether management is actually increasing its capacity to cope with future extremes”, Vacchiano adds.

Europe's forests will keep meeting climate shocks. The choice, the brief concludes, is between reacting after each damaging event and building the capacity to anticipate, absorb, recover and adapt.

Read the full policy brief: Forests at Risk: Measuring and Building Resilience Against Extreme Climate Events

A forest can still be standing while losing its capacity to recover

Credit

Evgeni Dimitrov/eLTER

Chemists unlock new possibilities for rare-earth metal

Researchers report method to isolate and separate terbium under non-lab conditions, potentially expanding its use

University of Iowa

Caged metal — image:
Chemists led by the University of Iowa have isolated the rare-earth metal terbium under normal environmental conditions, which could lead to greater uses. The illustration shows how the team devised a cagelike, molecular structure primarily composed of tungsten (gray) and oxygen atoms (red) that bound the terbium (brown), creating the conditions for the terbium atom to change its oxidation state and be separated.
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Credit: Korey Carter lab, University of Iowa

Chemists led by the University of Iowa in a new study report they have isolated and described in detail an atypical state of the rare-earth metal terbium, an advance that could expand its use, such as in quantum technologies that could include computing and advanced sensors.

Terbium, a silvery-gray metal mined primarily in China but also found in the United States and a few other countries, is central to a host of devices and technologies. The element underpins green phosphors, which are essential for televisions, fluorescent lamps and LED displays. It also plays a key role in solid-state devices, fuel cells, and has been used to improve the safety of medical X-rays by allowing the same quality image to be produced with a much shorter exposure time.

While useful, terbium comes with obstacles to its access and use. It is part of a group of elements called the lanthanides, a suite of metals that have nearly the same physical properties, which makes it challenging to separate them unless under rigid laboratory conditions.

The Iowa chemists, led by Korey Carter, assistant professor in the Department of Chemistry, and Pere Miro, associate professor in the Department of Chemistry, sought a way to separate terbium under normal environmental conditions, which would make the process cheaper and easier, thus enabling the metal’s full range of properties to be explored.

To do that, he and his team devised a cage-like, molecular structure consisting of metal and oxygen atoms that bound the terbium and caused it to change its oxidation state –essentially yielding a new version that could be isolated and studied in detail.

It's a proof of concept that shows how terbium, and potentially other lanthanides, can be more efficiently separated from each other, opening up new avenues for how each of these rare-earth metals could be used more widely.

“One of challenges with lanthanides is they prefer to be in the same oxidation state, and it’s tricky to change that state and thus separate one from another without it being performed in a tightly controlled environment, such as a lab,” says Carter, the study’s co-corresponding author. “But we devised a method to isolate, or separate terbium, by changing its oxidation state in an environment that doesn’t require specialized lab controls.”

That could open terbium, like other rare-earth metals, for wider use. One area is quantum technology, the unseen world where atoms and other smaller constituents act in strange, hard-to-predict ways.

Among the potential applications there could be computing and advanced sensors in navigation, medical imaging, and other fields.

Terbium, like the other lanthanides, prefers to be in a plus-3 oxidation state, terminology that refers to the number of floating, or “free,” electrons orbiting the nucleus. Terbium’s properties in the plus-3 oxidation state – where it’s most stable – have been well documented, but its characteristics in other states have been little explored.

One of those under-explored areas is the plus-4 oxidation state, in which terbium would have an electron removed, changing its charge and in essence turning it into a new species. But like a stubborn person, terbium resists being transformed and only succumbs when forced.

“You can compel it to give away or accept an electron,” Carter explains, “but it's generally energetically unfavorable.”

Researchers have turned terbium into the plus-4 oxidation state, but they did so in rigorous air-free environments, according to Carter.

His team sought to lower the barriers by creating a molecular assembly of tungsten and oxygen, or polyoxometalate, and adding binding agents known as ligands. With the terbium atom sandwiched in these cages, the Iowa chemists added a chemical oxidant called potassium persulfate. That initiated a reaction that caused the terbium atom to lose an electron, change its oxidation state, and thus be isolated. Moreover, Carter’s team isolated terbium in ambient conditions, meaning in an environment that didn’t require special controls, such as temperature, humidity, or pressure.

“If you were in your house and you were setting up a chemistry experiment, it would be analogous to what we were doing in the lab,” he says.

The benefit to changing terbium’s chemistry in a normal environment could make it easier to access and potentially broaden its applications, such as in quantum technologies or through knowledge gained to separate other metals, Carter says. His group now wants to take what they learned with separating terbium to investigating actinides, a group of highly radioactive elements used in cancer-fighting treatments and devices, such as powering cardiac pacemakers in the body and smoke detectors.

“Our findings highlight the ability to do transformative research at the University of Iowa, and they provide a platform to extend the chemistry to the actinide series in UI Radiochemistry laboratories,” Carter says.

The study is titled “Structural and spectroscopic characterization of a Tb(IV) polyoxometalate.” It was published on July 16 in the journal Nature Communications.

Miro is a co-corresponding author on the study. Other co-corresponding authors are Benjamin Stein and Stosh Kozimor, from Los Alamos National Laboratory; and Jennifer Wacker, from Lawrence Berkeley National Laboratory.

Contributing authors include Primadi Subintoro, Brett Lottes, S. Genevieve Duggan, Daniel Unruh, from Iowa; Felipe Pereiro, from Los Alamos and the Colorado School of Mines; Nolwenn Mahieu, Alexander Brown and Joshua Woods, from Lawrence Berkeley; Monica Mullis, Aldo Jordan, Cassandra Gates and Samuel Greer, from Los Alamos; Rebecca J. Abergel, from Lawrence Berkeley and the University of California-Berkeley; and Jenifer Shafer, from the Colorado School of Mines.

The research was funded by the U.S. Department of Energy.

Journal

Nature Communications

DOI

10.1038/s41467

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Structural and spectroscopic characterization of a Tb(IV) polyoxometalate

Study confirms Canada's last epishelf lake is gone for good

Loss of the millennia-old ecosystem shows that even the Arctic's projected last ice refuge is vulnerable to rapid change

University of British Columbia

Bernard Laval and Jérémie Bonneau — image:
Dr. Bernard Laval (right) and Dr. Jérémie Bonneau
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Credit: Jérémie Bonneau

Canada’s last epishelf lake drained into the Arctic Ocean following the 2020 breakup of the Milne Ice Shelf and will not recover, a new study confirms.

Epishelf lakes form when an ice shelf acts as a dam, trapping a layer of freshwater floating above seawater connected to the ocean. The Milne Fiord epishelf lake, located on northern Ellesmere Island in Nunavut, supported freshwater microorganisms near the surface and marine species below.

In July 2020, the Milne Ice Shelf broke apart, losing 45 per cent of its area and removing the barrier that held the freshwater in place.

Drawing on a decade of ocean measurements, satellite imagery, and field observations collected before and after the breakup, researchers from UBC, University of Alberta, Université Laval and Carleton University reconstructed the lake’s disappearance.

Their findings show that the freshwater layer began escaping immediately after the collapse and had mostly vanished by autumn 2020.

"The ice shelf and lake had been thinning for decades, but the 2020 breakup was the last straw. The lake drained within months," said study author Dr. Jérémie Bonneau, a professor of civil and water engineering at Université Laval who conducted part of the research during his PhD at UBC.

The first field measurements collected after the breakup showed that by July 2022, brackish water had fully replaced the lake's distinct freshwater layer. Annual monitoring since then has found no sign of recovery.

"Epishelf lakes can signal when an ice shelf is under stress, and that's what we saw here," said co-author Dr. Bernard Laval, a professor of civil engineering at UBC who leads its environmental fluid mechanics research group. "The data showed the ice shelf was failing. Once the ice is gone, the ecosystem goes with it. There's no coming back."

“Epishelf lakes are remarkable because a freshwater ecosystem sits directly above a marine one, separated only by a thin boundary between fresh water and salt water,” said co-author Dr. Andrew Hamilton, a research scientist at the University of Alberta who completed his PhD research at Milne Fiord. “When the ice shelf broke apart, that unique ecological structure disappeared.”

Dr. Derek Mueller, a professor of geography and environmental studies at Carleton University, established the research program that tracked the ice shelf and lake through years of accelerating change.

"There are much easier places to conduct research, but understanding change in the High Arctic requires returning year after year," said Dr. Mueller. "When we began this work, we knew the ice shelf and epishelf lake were vulnerable and designed this project to monitor the transition of the fiord from one with an epishelf lake and an ice shelf to one that is seasonally ice-free. We anticipate further profound changes in the coming years."

The research team included co-authors Silas Pijamini and Joseph Shoapik from Ausuittuq (Grise Fiord), who have participated in fieldwork since 2022.

A decade of data captures the loss

Published in Scientific Reports, the study provides the first complete reconstruction of the lake's drainage and its transformation from a freshwater ecosystem into a marine environment.

Researchers analyzed data from instruments anchored in Milne Fiord, along with annual water profiles, satellite imagery and field observations. Instruments left in place during the COVID-cancelled 2020 field season recorded the lake’s rapid salinization, though researchers could not retrieve the data until two years later.

The study found that freshwater entering Milne Fiord is now flushed directly into the ocean because the remaining ice shelf can no longer contain it. Re-establishing the lake would require the ice shelf to recover, which is not possible under the current climate trajectory.

Loss reaches the Last Ice Area

The Milne Ice Shelf lies within the Last Ice Area, a region expected to retain perennial sea ice longer than anywhere else in the Northern Hemisphere. It is also within the Tuvaijuittuq Marine Protected Area, whose name means "the place where the ice never melts" in Inuktitut.

The loss of the lake shows that even this potential refuge for ice-dependent ecosystems is undergoing rapid change.

"These systems took thousands of years to form and were lost in months," said Dr. Bonneau. "On any human timescale, they are not coming back."

Interview languages: English (Bonneau, Hamilton, Laval, Mueller), French (Bonneau, Laval)

Photo gallery of the research available for media use, with credits: https://wirl.carleton.ca/photo-gallery/

For more information on the loss of Arctic ice shelves in Summer 2020, visit https://wirl.carleton.ca/research/ice/ice-shelves/calving-2020/

SIDEBAR:

Science at the edge of the ice

Reaching Milne Fiord takes the better part of a week in a good year.

From Vancouver or Quebec City, researchers take multiple flights — to Ottawa, Iqaluit and then Resolute Bay via Arctic Bay. In Resolute, the team spends several days at the federal Polar Continental Shelf Program base, preparing equipment and weighing every load.

“The Twin Otter can carry only about 1,000 kilos,” said Dr. Jérémie Bonneau. “Everything has to be weighed and balanced before we go.”

From Resolute, the team flies to Eureka to refuel before continuing to Purple Valley near Milne Fiord.

“I’ve been delayed for 12 days because of poor weather,” said Dr. Bonneau. “You need to plan for about a month. The actual work, when conditions allow, may be only five or six days.”

Fieldwork takes place in July, when snowmelt allows aircraft with wheels to land. Researchers can travel about 10 kilometres from camp on foot, while helicopters connect them with instruments across the wider study area. Low cloud and poor visibility, however, can prevent flying about half the time.

The research program has brought scientists back to Milne Fiord for nearly two decades, building the long-term record that allowed the team to reconstruct the lake’s disappearance.

The team collects measurements using sensor tubes about the size of a thermos. The instruments record temperature, depth and conductivity, which researchers use to determine the water’s salt content.

The researchers also maintain a long-term mooring: a set of instruments anchored to the seafloor and held upright by buoys, recording conditions throughout the Arctic winter. Each summer, the team hauls the equipment up through the ice, downloads the data, replaces its batteries and redeploys it.

Those instruments remained in place during the COVID-cancelled 2020 field season and recorded the lake’s drainage, which no researchers were there to witness.

“We saw the breakup in satellite images, and two years later we got the data,” said Dr. Laval. “The instruments were there, observing. We just couldn’t reach them.”

Bernard Laval retrieving a mooring in a Milne Ice Shelf pond.