A novel strategy for detecting trace-level nanoplastics in aquatic environments: Multi-feature machine learning-enhanced SERS quantification leveraging the coffee ring effect

Compuscript Ltd

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Figure 1. Novel SERS detection strategy for nanoplastics based on coffee ring effect.

view more 

Credit: OEA

A new publication from Opto-Electronic Advances; DOI  10.29026/oea.2025.240260 discusses a novel strategy for detecting trace-level nanoplastics in aquatic environments.

 

Plastic materials have revolutionized human lifestyles through their versatile applications, yet their environmental legacy now presents critical challenges to global ecosystems and public health. Current models estimate annual plastic influx into aquatic systems at 4.8-12.7 million metric tonnes, with projections suggesting cumulative marine plastic accumulation could reach 12 billion metric tonnes by mid-century an environmental crisis demanding urgent scientific attention. Nanoplastics are one of the many plastic wastes that are usually less than 1 μm in size, it has multiple sources, is widely distributed in soil and water environments, and can enter the body through breathing and eating. Nanoplastics present unique biological hazards, possessing enhanced capacity to traverse biological barriers through cellular membrane penetration while serving as persistent organic pollutant vectors through surface adsorption, thereby amplifying ecotoxicological impacts.

 

There are many methods for detecting nanoplastics, including transmission/scanning electron microscopy, dynamic light scattering, nanoparticle tracking analysis. Among the many detection methods for nanoplastics, surface-enhanced Raman spectroscopy (SERS) is an electromagnetic field enhancement phenomenon mainly based on the resonance of light between precious metal particles, can not only accurately reflect the chemical bonding information of the nanoplastics to be tested, but also provide high-resolution imaging of the morphology of the nanoplastics to be tested, and thus has received widespread attention in the field of nanoplastics detection.

 

However, critical limitations persist in translating this technology to environmental monitoring applications, particularly regarding quantitative analysis of trace-level nanoplastics. Field samples typically contain nanoplastic concentrations in the μg/L range, where conventional SERS substrates demonstrate insufficient sensitivity for practical monitoring requirements. This analytical challenge stems from fundamental physical constraints: at ultralow concentrations, stochastic nanoparticle distribution creates sparse deposition patterns where interparticle distances exceed typical laser spot dimensions (~1 μm). This spatial dispersion results in minimal signal variance across concentration gradients, as most sampled regions contain comparable nanoparticle counts, effectively nullifying intensity-based quantification methods dependent on characteristic peak amplitude variations.

 

To address these challenges, a research team from the School of Physics and Electronic Science at Shandong Normal University has proposed an innovative SERS detection strategy leveraging the coffee ring effect. Experimentally, the team first developed a superhydrophobic CuO/Ag SERS substrate with enhanced sensitivity to generate the coffee ring effect. Crucially, they employed an infrared radiation technique during the hydrophobic modification process, effectively eliminating potential interference caused by traditional organic modifiers such as fluorosilanes and stearic acid. This methodological advancement ensures cleaner spectral signatures while maintaining substrate functionality for precise nanoplastic detection.

 

The experimental results further demonstrated that when a nanoplastic-containing solution is deposited on this substrate surface, the Marangoni flow within the droplet transports "coffee particles" (nanoplastics) toward the droplet periphery, forming a distinct coffee ring upon drying. Owing to the pinning effect, nanoplastics become concentrated within the coffee ring structure, effectively addressing the challenge of insufficient Raman signal differentiation caused by nanoparticle dispersion at low concentrations. During experimentation, the research team observed an inverse correlation between the inner diameter of the coffee ring and nanoplastic concentration in the solution. Moreover, the coffee ring's enrichment effect enables efficient Raman mapping scans within smaller detection areas even at low nanoplastic concentrations, yielding abundant valid spectral data. Notably, the detection probability of valid Raman spectra within the scanned area also exhibits an inverse relationship with nanoplastic concentration. This dual observation establishes a novel quantification framework: at low concentrations, nanoplastic levels can be determined not only through spectral identification but also via coffee ring diameter measurements and detection probability analysis within the ring.

 

Remarkably, the superhydrophobic CuO/Ag SERS substrate not only generates intense electromagnetic hot spots for signal enhancement but also provides multiple concentration-dependent detection parameters. By integrating machine learning algorithms to analyze three distinct features (signal intensity, coffee ring diameter, and detection probability) through multivariate analysis, the team achieved breakthrough quantification performance. Across a broad concentration range (1% to 10-10%), the multivariate approach demonstrated mean squared errors (MSE) of 0.54 (PLSR) and 0.21 (SVR)—a 19-fold improvement over traditional linear regression based solely on characteristic peak intensity variations (MSE=4.06). Furthermore, this method achieved an ultralow quantification limit of 10-10%, establishing unprecedented sensitivity for environmental nanoplastic detection.

 

This work innovatively combines SERS technology with surface wettability engineering, simultaneously preserving the technique's inherent advantages of high sensitivity and molecular fingerprint specificity while overcoming the critical limitation of unreliable Raman intensity-concentration correlations at ultralow analyte levels. The demonstrated operational practicality establishes a transformative framework for nanoplastic detection, offering a novel paradigm for conducting precise SERS-based measurements in environmental monitoring scenarios. This methodological breakthrough holds significant implications for advancing risk assessment protocols and developing mitigation strategies against nanoplastic contamination in agricultural ecosystems.

 

Keywords: quantitative detection of trace nanoplastics / surface-enhanced Raman scattering / coffee ring / multiplex-feature analysis / machine learning

 

# # # # # #

Figure 2. Hydrophobic CuO/Ag SERS substrate morphology.

Figure 3. Machine learning algorithm based analysis of multiple features of coffee rings formed by nanoplastic droplets.

Credit

OEA

Jing Yu (corresponding author of this paper) is an Associate Professor at the School of Physics and Electronics, Shandong Normal University. His long-term research focuses on innovative explorations of structural light field manipulation in surface-enhanced Raman scattering (SERS) and analytical model development. Currently, he leads the "Ultra-Sensitive In-Situ Spectral Detection Innovation Team" supported by the Shandong Provincial Higher Education Youth Innovation Science and Technology Support Program. He has completed five national and provincial/ministerial-level research grants as principal investigator.

 

Over the past five years, he has published over 30 SERS-related papers as first or corresponding author in prominent SCI-indexed journals including Opto-Electronic Advances, Advanced Functional Materials, Nano Energy, Small, ACS Photonics, Analytical Chemistry, Applied Physics Letters, Advanced Optical Materials, etc., accumulating over 4,100 citations. His research achievements have earned multiple honors, including the 2023 Second Prize of Shandong Natural Science Award and the 2020 First Prize of Shandong Higher Education Institutions Science and Technology Award.

 

Chao Zhang (corresponding author of this paper) is the Associate Dean for Academic Affairs at the School of Physics and Electronics, Shandong Normal University, a Taishan Scholar Young Expert, a recipient of the Shandong Provincial Outstanding Youth Scholar award, and the Director of the Condensed Matter Physics Degree Program at Shandong Normal University. His long-term research focuses on surface plasmon-enhanced spectroscopy.

 

He has led over 10 major research projects, including the National Natural Science Foundation of China (NSFC) General Program, Youth Program, and the Shandong Provincial Outstanding Youth Fund. Under his leadership, the "Low-Dimensional Materials and Devices Youth Innovation Team" was recognized as an Innovation Team under the Shandong Provincial Higher Education Youth Innovation Science and Technology Support Program.

 

As first or corresponding author, he has published more than 60 papers in leading optics journals such as Opto-Electronic Advances, Laser & Photonics Reviews, and Advanced Functional Materials, including two invited review articles. His work has garnered 6,188 total citations, with a single paper receiving up to 242 citations. Notably, he has been consistently ranked among the top 2% of the World's Top Scientists list for five consecutive years (2020-2024).

 

# # # # # #

Opto-Electronic Advances (OEA) is a rapidly growing high-impact, open access, peer reviewed monthly SCI journal with an impact factor of 15.3 (Journal Citation Reports for IF2023). Since its launch in March 2018, OEA has been indexed in SCI, EI, DOAJ, Scopus, CA and ICI databases over the time, and expanded its Editorial Board to 34 members from 17 countries.

# # # # # #

 

 

More information: http://www.oejournal.org/oea

Editorial Board: http://www.oejournal.org/oea/editorialboard/list

All issues available in the online archive (http://www.oejournal.org/oea/archive).

Submissions to OEA may be made using ScholarOne (https://mc03.manuscriptcentral.com/oea).

ISSN: 2096-4579

CN: 51-1781/TN

Contact Us: oea@ioe.ac.cn

Twitter: @OptoElectronAdv (https://twitter.com/OptoElectronAdv?lang=en)

WeChat: OE_Journal

# # # # # #

 

Lin XN, Lei FC, Liang X et al. Quantitative detection of trace nanoplastics (down to 50 nm) via surface-enhanced raman scattering based on the multiplex-feature coffee ring. Opto-Electron Adv 8, 240260 (2025). doi: 10.29026/oea.2025.240260 

 

---

Journal

Opto-Electronic Advances

DOI

10.29026/oea.2025.240260 

 

Increase in alcohol deaths in England an ‘acute crisis’

University College London

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

The persistent higher rate of alcohol deaths in England since the pandemic in 2020 is an “acute crisis” requiring urgent action from government, according to a new study led by researchers at UCL and the University of Sheffield.

For the study, published in Lancet Public Health, researchers analysed Office for National Statistics (ONS) figures of deaths caused solely by alcohol in England. They found that death rates were stable between 2009 and 2019, but increased by a fifth in 2020, rising by a further 13.5% between 2020 and 2022.

The team estimated that 3,911 more people had died solely because of alcohol in England between 2020 and 2022 than would have been the case if pre-pandemic trends had continued.

The largest increases were among groups most likely to be affected before the pandemic – men, people from deprived areas, and those aged 50 to 69. The main cause, the researchers found, was a steep rise in liver damage caused by alcohol. Deaths from acute causes such as alcohol poisoning also increased.

The latest ONS figures from 2023, though not analysed by the new study, show alcohol deaths continuing to rise in England, up to 8,274*.

Lead author Dr Melissa Oldham, of the UCL Institute of Epidemiology & Health Care, said: “The sharp increase in alcohol deaths during the pandemic was no flash in the pan. The higher rate has persisted and is getting worse each year.

“It is an acute crisis, and urgent action is needed to prevent further avoidable deaths. This includes substantial investment in health services to better detect and treat liver disease as well as policies to reduce alcohol consumption in the population as a whole, such as minimum unit pricing and advertising restrictions.”

Senior author Professor Colin Angus, of the University of Sheffield’s School of Medicine and Population Health, said: “The increase in alcohol deaths is entrenching existing health inequalities, with large absolute increases among men and among people from deprived areas. Men, just as before the pandemic, are twice as likely to die because of alcohol compared to women, with almost three times as many additional alcohol-specific deaths in the most deprived areas compared to the least deprived.”

In the paper the researchers said the increase in liver disease deaths may be partly explained by an increase in drinking among heavier drinkers and by more frequent binge drinking, as well as reduced access to health services during the pandemic and reduced treatment seeking. Increases in drinking seen during the pandemic and lockdowns do not seem to have returned to pre-pandemic levels, which could partly explain the continuing increase in alcohol-specific deaths each year.

They said obesity may be a factor, as increased drinking during the pandemic lockdowns may have been accompanied by weight gain and a more sedentary lifestyle, and obesity increases the risk of an alcohol-related liver disease death. Covid-19 may also have had an impact, as having established cirrhosis (scarring of the liver) is linked to a two- to threefold risk of death from a Covid-19 infection, the researchers said.

Co-author Dr Gautam Mehta, of the UCL Division of Medicine, said: “There are marked inequities in the provision of liver care in England. The average age of death from liver disease is nine years lower in the most deprived parts of the country, compared to the least. And, overall, rates of death following a hospital admission with liver cirrhosis are several times higher than comparable admissions for stroke or heart disease. New treatments and strategies for earlier detection are urgently needed.”

Persistent higher alcohol death rates since the pandemic have also been reported in Germany, Estonia, Latvia, Bulgaria, Australia, and the United States.

The researchers added that it was unclear why changes in alcohol consumption at the start of the pandemic had persisted, when for most people day to day life had returned to pre-pandemic routines.

This could be that habits formed during the lockdowns were difficult to break. They suggested that, in England, it could be linked to the cost-of-living crisis, as well as worse mental health, with higher rates of severe psychological distress reported in England between 2020 and 2022.

The study used the ONS definition of alcohol deaths as those registered on the death certificate as having an underlying cause that is wholly attributable to alcohol. This excludes deaths caused partially by alcohol such as alcohol-related cancers or road traffic accidents.

The researchers received funding from the Society for the Study of Addiction, Cancer Research UK and the National Institute for Health Research.

Dr Katherine Severi, Chief Executive, Institute of Alcohol Studies, said: “It’s shocking to see that almost 4,000 more people died in England from alcohol than was expected since the pandemic, with the number continuing to rise.

“We’ve known for years now that changing drinking habits during lockdowns increased levels of alcohol harm – this study underlines the impact that had on worsening health inequalities across England.

“The government has made tackling inequalities one of its health priorities. There is no way of doing that without introducing a comprehensive alcohol strategy that tackles cheap, excessively available, and aggressively marketed alcohol.”

Professor Sir Ian Gilmore, Chair, Alcohol Health Alliance, said: “Five years on from the start of the pandemic, we are still seeing the devastating consequences of increased alcohol consumption. Drinking trends have not returned to pre-pandemic levels, and the latest data confirms that alcohol-specific deaths remain at record highs – hitting those who were already at greatest risk before the pandemic the hardest.

“Alarmingly, the burden of alcohol harm continues to fall disproportionately on the most deprived communities, and it is deepening existing health inequalities. The government must act urgently to introduce evidence-based policies, such as minimum unit pricing, to reduce alcohol harm and save lives.”

---

Journal

The Lancet Public Health

Method of Research

Observational study

Subject of Research

People

Article Title

Trends in alcohol-specific deaths in England between 2001-2022: an observational study

Article Publication Date

10-Apr-2025

 

UK Government urged to tackle inequality in ‘low-carbon tech’ like solar panels and electric cars

University of Sheffield

• Decarbonisation in the automotive and housing sectors is paramount if the UK’s legally binding commitment to achieving net zero by 2050 is to succeed, say researchers at University of Sheffield

• Exploring the presence of socioeconomic inequalities in the uptake of low-carbon technologies (LCTs), such as solar panels and electric vehicles, has important policy implications for the decarbonisation in the UK

• The new report advocates for interventions at an individual, as well as community-level, to help those from more disadvantaged backgrounds adopt technologies that could lower their household bills,

• Education, age, occupation, gender and ethnicity are all contributing factors in an individual's ability to adopt LCTs

The UK government needs to go beyond offering subsidies for low-carbon technologies (LCTs) like electric cars and solar panels for energy and heating, if it is to meet its net-zero targets by 2050, a new report from the University of Sheffield suggests.

The report, published with partners from the universities of Nottingham and Macedonia, found that although gains are being made in encouraging people to adopt low-carbon technologies, not enough is being done to continue to reduce the inequalities in uptake amongst some socioeconomic groups.

In recent years households using solar panels for electricity generation has increased from 3 to 6.5 per cent, the adoption of solar panels being used for heating increased from 1.4 to 2.1 per cent and households using an electric or hybrid-electric vehicle increased from less than 1 per cent to 2.8 per cent, reflecting the growing adoption of LCTs nationally.

However, the study found that although socioeconomic inequalities in LCTs adoption have decreased over the past decade, they still persist. Factors such as age, education, occupation, ethnicity and gender all contribute directly and indirectly to people’s ability to invest in LCTs. 

The report authors say more needs to be done to level the playing field, and help those from more disadvantaged backgrounds adopt technologies that could lower their household bills, and contribute to the UK’s decarbonisation in the housing and automotive sectors.

Dr Andrew Burlinson, from the University of Sheffield’s School of Economics, said: “Our research suggests that some socioeconomic groups have not been adequately supported to adopt LCTs. So it is important to emphasise that by limiting the ability of the most disadvantaged groups to invest in technology that can lower their bills and increase resilience to fluctuating living costs – such as current high energy prices – may further exacerbate broader inequalities in our society.

“Our analysis reveals that educated and affluent households are more likely to have been able to adopt low-carbon technologies early, such as solar energy, solar heating and electric or hybrid transport. 

“Yet some existing financial subsidies to help people transition to LCTs have now ended, so those members of society who were unable to become early-adopters are now being left behind in the transition to net-zero.”

The UK government currently subsidises the purchase of some types of electric vehicles at the point of sale, but these subsidies are largely independent of the socioeconomic status of the consumer. Alongside this, subsidies to install domestic solar panels ended in 2019, which means that incentives to help people adopt LCTs are now limited, and may be working less well for those members of society with a lower socioeconomic status.

The authors say exploring the presence of socioeconomic inequalities in LCTs in the UK has important policy implications for the low-carbon transition, and the achievements of the UK government's ambitious and legally binding environmental targets.

There are positive signs that some consumers are increasingly adopting more sustainable ways to live and travel. But the Climate Change Committee reports that for the UK to make significant gains in reaching its net-zero targets, the market share for new electric vehicles needs to be at 100 per cent, from only 16.5 per cent today, and that solar panel installation rates need to increase by five times that of current levels.

Professor Monica Giulietti, from the University of Nottingham, said: “In our report and new policy brief, we suggest it is vital that new interventions should be targeted towards those groups that could potentially benefit the most from cost-reducing technologies, not just at individual level but at a community level as well. This action will rely on addressing policy gaps in the private, rented and social housing sectors.”

As well as more targeted financial incentives for those of a lower socioeconomic position, the report calls for information incentives provided by trusted organisations to establish educational guidance and increase awareness of LCTs; to help those most in need navigate decision making about adoption.

The report also argues that new interventions need to be made at community level. Rather than advocating for solar technology just for individual households, a shift towards community installations is suggested to help alleviate the cost burden of adoption, and help level the playing field for those who do not have individual control over their property or transport.

Commenting on the research, Dr Jayne Carrick, from the South Yorkshire Sustainability Centre, said: “A recent survey conducted by the South Yorkshire Sustainability Centre into the region’s energy consumption habits revealed a significant hurdle to low-carbon technologies: 46 per cent of residents are reluctant to adopt solar panels, and 57 per cent are hesitant about heat pumps.

“Much more needs to be done in UK policy to address the inequality in uptake and beyond. For example, the opportunity to unlock the power of community energy initiatives is a crucial area, streamlining processes and fostering collective investment to make LCTs accessible for all.”

Dr Andrew Burlinson added: “The findings of the new report add to the growing debate on the low individual uptake of LCTs, and the problems created for consumers from more disadvantaged backgrounds when access to the benefits of low-carbon technologies is unequally distributed.

“Our results lead us to support policies targeting specific socioeconomic groups at individual and community level, which is not only crucial to mitigate the observed inequalities in LCT adoption, but also relevant in promoting energy efficiency and resilience to high energy prices as we transition towards a low-carbon future.”

---

Journal

Energy Economics

DOI

10.1016/j.eneco.2025.108244 

Article Title

Socioeconomic inequality in low-carbon technology adoption

 

Caspian Sea decline threatens endangered seals, coastal communities and industry

University of Leeds

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

A white, fluffy Caspian seal pup looks at the camera while sitting on some ice.

view more 

Credit: ©Sarah DelBen, Central Asian Institute of Ecological Research (CAIER), Almaty, Kazakhstan

Urgent action is needed to protect endangered species, human health and industry from the impacts of the Caspian Sea shrinking, research led by the University of Leeds has found.

Water levels in the Caspian Sea – the world’s largest landlocked water body – are getting lower, as hotter temperatures cause more water to evaporate than is flowing in. Even if global warming is limited to below 2°C, it is likely that the level of the Caspian Sea will decline by 5 to 10 m, but if temperatures rise further, water levels could drop by as much as 21 m by 2100. 

Researchers led by Leeds have mapped the potential risks this poses to the region’s biodiversity and human infrastructure, in a paper published today (Thursday 10 April) in Communications Earth & Environment. 

The findings show that an area of 112,000 km² – which is larger than the size of Iceland – is likely to dry up, even in an optimistic scenario for global warming with a 10 m decline. Since many of the most ecologically and economically important areas are located in shallow water, this could have significant consequences for biodiversity and the sustainability of the region’s human population.  

The Caspian Sea is home to the endangered Caspian seal and six species of sturgeon, as well as hundreds of species of fish and invertebrates found nowhere else. According to the research, the declining water levels will leave Caspian seals with significantly reduced breeding habitat, restrict access to spawning rivers for sturgeons, and lead to the loss of coastal lagoons and reed beds important for the spawning of other fish species and migrating birds. 

More than 15 million people live around the Caspian coast, in Azerbaijan, Iran, Kazakhstan, Russia and Turkmenistan. The bordering nations rely on the water body for fishing, shipping and trade, and the sea is important for regulating climate in Central Asia.  

In the northern Caspian, the findings show that some settlements, ports and industrial facilities could end up being stranded tens or even hundreds of kilometres from new shorelines. The exposed dry seabed is likely to release dust containing industrial contaminants and salt, posing serious threats to human health, as previously occurred with the drying of the Aral Sea. 

The researchers say policymakers and conservationists need to take a dynamic approach to biodiversity protection, rather than relying on traditional protected areas with fixed boundaries, since these may quickly become obsolete due to the rapidly changing water levels. 

Dr Simon Goodman from the School of Biology at the University of Leeds, who supervised the research, said: “Some Caspian Sea level decline appears unavoidable, even with action to reduce global greenhouse gas emissions. However, with the anticipated effects unfolding over a few decades, it should be possible to find ways to protect biodiversity while safeguarding human interests and wellbeing. That might sound like a long timescale, but, given the immense political, legislative and logistical challenges involved, it is advisable to start action as soon as possible to give the best chance of success.” 

Biodiversity 

Currently the Caspian Sea extends approximately 1150 km by 450 km, with a total area of 387,000 km². 

With a 10 m decline, four out of 10 ecosystem types unique to the Caspian Sea would be expected to disappear completely, and the coverage of existing marine protected zones (areas earmarked for conservation) would be reduced by up to 94%. 

Caspian seals give birth to their white-coated pups between mid-January and early March on ice in the northern Caspian Sea. However, the research shows a 5 m decline could reduce the area of this habitat by up to 81% - putting huge stressors on their already reduced population.  

The Caspian seal was listed as Endangered by the International Union for the Conservation of Nature (IUCN) in 2008, and is included in the national Red Books of all five Caspian countries, signifying its recognition as a species at risk of extinction.   

The decline will also make all current and historical haul-out sites – areas on land where seals rest – inaccessible. While receding water levels may create some new islands, further research is needed to assess their suitability for seals. 

Sturgeons are an ancient family of large fish, and critically endangered due to overfishing for their meat and caviar (fish eggs or roe). The fish usually inhabit shallower parts of the sea in summer and autumn, but these areas are facing a potential reduction of 25% to 45% due to the fall in water levels, which may stop them accessing their few remaining spawning sites in rivers that flow into the Sea.  

The Caspian Sea is also a globally important habitat for birds migrating between Europe, Asia and Africa. Migratory birds rely on coastal lagoons and reed beds for resting, shelter and food during their migrations, but such habitats are vulnerable to loss as waters recede. 

Biodiversity in the Caspian Sea is already threatened by over-fishing, introduction of invasive species and pollution. Although work has been done to protect areas important for biodiversity, the paper predicts that overall coverage of existing Caspian marine protected areas disappear almost entirely for all countries except Kazakhstan, which would retain about 5% of current coverage. 

Rebecca Court, PhD researcher in the School of Earth and Environment at Leeds, worked on the research as part of her Masters degree in the School of Biology. She said: “We hope this research will help to raise awareness of the trajectory and potential impacts of the falling sea level. The mapping should better equip policymakers and conservationists to plan for and address the numerous issues in advance.” 

Industry and society 

The findings also predict a concerning trajectory for industry, with critical ports in all bordering countries being impacted. Baku (Azerbaijan), Anzali (Iran), and Aktau (Kazakhstan) are expected to experience increases in distance to shore of 1 km or more, while Turkmenbashi (Turkmenistan), and Lagan (Russia; planned future site), could see increases of 16 km and 115 km respectively, according to the paper. 

The Volga is the only river connecting the Caspian to the outside maritime world, and this vital trade route could be critically compromised by declines of just 5 m.  

The Kashagan (Kazakhstan) and Filanovsky (Russia) oil fields in the northern Caspian are two of the region’s most important hydrocarbon production sites. Production currently occurs at offshore installations, with ship-based logistics, but these will become landlocked if Caspian Sea levels decline by 5 to 15 m.  

Coastal communities in the north are likely to be hit hard as income from fishing disappears, and harsh climatic conditions make other economic activity like agriculture more difficult, potentially threatening social stability. 

Some cities around the Caspian use desalination (removing salt and minerals from saltwater) for fresh water supplies, and water level declines are already impacting desalination operations at Aktau in Kazakhstan.   

Loss of water from the Caspian could also affect the regional climate, leading to reduced rainfall and drier conditions across central Asia with indirect impacts on agriculture.  

The energy resources of the Caspian Sea make it important geopolitically, so social, economic and environmental instability due to climate change could have worldwide repercussions. 

Recommendations 

Going forward, a balance needs to be struck between protecting biodiversity and human prosperity and wellbeing. The researchers’ recommendations include:

• Investing to enhance regional capacity for biodiversity monitoring, conservation planning and sustainable development 

• Supporting coastal communities to diversify economically and develop resilient infrastructure 

• Developing legislation that enables the creation of protected areas with flexible borders 

• Taking a pre-emptive planning approach to avoid conflicts between biodiversity protection and efforts to adapt human infrastructure 

• Tracking rapidly changing ecosystems and implementing species translocations and ecosystem restoration where needed 

• Reducing greenhouse gas emissions at a global scale.  

The researchers stress that urgent action is needed, with coordinated regional planning and global collaboration, to mitigate the projected impacts.

Dr Elchin Mamedov from the Ministry of Ecology and Natural Resources, Azerbaijan, said: "This is an important study because it highlights the risks posed by climate change for Caspian region biodiversity and local communities and the need to enhance regional and international cooperation to help manage the impacts."

The international collaboration involved researchers from Technische Universität Braunschweig (Germany), Technische Universität Berlin (Germany), Kaspika Caspian Seals Conservation Agency (Russia), Institute of Hydrobiology & Ecology (Kazakhstan), Museum of Natural History (Azerbaijan), Central Asian Institute of Ecological Research (Kazakhstan), Fisheries and Aquaculture Research Centre (Azerbaijan), Ramsar Regional Initiative of Central Asia (Turkmenistan), University of Bremen (Germany) and Justus Liebig University Giessen (Germany). 

---

Journal

Communications Earth & Environment

DOI

10.1038/s43247-025-02212-5 

Subject of Research

Not applicable

Article Title

Court R., Lattuada M., Shumeyko N., Baimukanov M., Eybatov T., Kaidarova A., Mamedov E. V., Rustamov E., Tasmagambetova A., Prange M., Wilke T., Hassall C., Goodman S. J. (2025). Rapid decline of Caspian Sea level threatens ecosystem integrity, biodiversity protection, and human infrastructure. Communications Earth and Environment.

Article Publication Date

10-Apr-2025