Where does Earth's nitrogen go? Two atoms offer a clue

A rare atomic fingerprint reveals how nitrogen cycles through the biosphere

University of California - Santa Barbara

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(Santa Barbara, Calif.) — Nitrogen is one of life’s building blocks, but it’s only helpful in the right amounts. Too much nitrogen in water, for example, can lead to poor water quality and the gradual death of aquatic organisms. Microbes remove nitrogen from water by converting it to a gas that escapes into the atmosphere. But scientists have difficulty determining how much nitrogen is removed this way.

Biogeochemists at UC Santa Barbara, UCLA and collaborating institutions have shown that a rare form of nitrogen gas can act as a natural fingerprint for microbial nitrogen conversion. The study, published in Science, reveals microbial nitrogen loss that conventional methods obscure.

The technique requires sophisticated machinery, so it won't find its way into routine field monitoring any time soon. However, it offers a new tool to improve water-quality assessments and estimates of the global nitrogen budget.

“The problem is that our water naturally has a huge amount of nitrogen gas that is dissolved from the air, so the gas that microbes produce can be very difficult to see,” explained first author Jiarui Liu, who conducted the research as a postdoctoral fellow at UCSB’s Marine Science Institute and at UCLA. “The answer is written in the way nitrogen atoms are paired inside the nitrogen molecule.”

The nitrogen cycle

Nitrogen is essential for proteins and DNA, yet most organisms can’t use nitrogen gas directly from the atmosphere. As nitrogen cycles through air, water and life, some microbes convert the gas into usable compounds while others return those compounds to gas. The balance between these processes helps determine how much nitrogen is available to support life. However, quantifying these processes has proven challenging.

Nitrogen gas, or N2, consists of two nitrogen atoms joined together. These come in two weights, called isotopes: the common nitrogen-14 and the heavier nitrogen-15, which has one extra neutron. Most N2 molecules contain two nitrogen-14 atoms; some contain one of each isotope; and very rarely, both atoms are nitrogen-15.

In atmospheric nitrogen gas, the two heavy nitrogen-15 atoms pair up more often than expected by chance. Meanwhile, the nitrogen gas produced by microbes has atoms paired nearly at random. When nitrogen from microbes mixes with nitrogen from the air, it reduces that excess of heavy pairs. As a result, the relative abundance of the rare molecule can reveal how much nitrogen gas was produced by microbial activity.

Using a bigger machine

The team measured nitrogen gas extracted from water and sediment samples using UCLA’s Panorama mass spectrometer. The instrument uses electric and magnetic fields to separate molecules according to their mass and charge. Usually, the rare nitrogen pairs are difficult to distinguish because other molecules have almost exactly the same mass. But Panorama’s unusually large size enables it to separate molecules with these tiny differences in mass.

“At UCLA we discovered the anomalous pairing of heavy nitrogen atoms in Earth’s atmosphere and are now making use of this signature of nitrogen in air as a powerful and unique geochemical tool,” said geochemist Edward Young, one of the paper’s co-authors and Liu’s postdoctoral advisor at UCLA.

The study brought together researchers working in groundwater, lakes and marine environments. Their combined field and laboratory expertise made it possible to apply the approach to Texas groundwater, lakes in Antarctica and Minnesota, coastal basins off Southern California, the Bay of Bengal and deep-sea sediments offshore from Alaska.

Results with global reach

In modern times, fertilizer runoff, wastewater discharge and other human activities have played an increasingly large role in the nitrogen cycle. Excess nitrogen from these sources can degrade water quality and fuel harmful algal blooms. As blooms die off, their decay consumes oxygen and can create low-oxygen “dead zones” that threaten fish and other aquatic life.

Studying the nitrogen cycle helps scientists identify how people can intervene to reduce or remediate environmental harm. By measuring how much nitrogen microbes remove naturally, the approach can help assess fertilizer and wastewater inputs and inform efforts to protect water quality.

“We want to understand whether microbes in groundwater can mitigate nitrate pollution, and how much nitrogen is removed along the way before it can fuel algal growth in lakes, rivers and coastal waters,” Liu said. “This gives us a clearer picture of whether nitrogen stays in an ecosystem or is removed from the nutrient pool as N2 gas.”

The approach could also address a gap in groundwater monitoring. “Many routine groundwater-quality monitoring programs do not measure the N2 gas produced within an aquifer, which can create substantial biases in our accounting of where nitrogen comes from and where it goes,” said co-author Alan Seltzer, assistant professor of hydrogeology at University College Dublin. “This study, and this exciting new technique, opens the door to a much more complete picture of the sources and fate of nitrogen in groundwater systems.”

The broader goal is to understand the pace of Earth’s nitrogen cycle. Scientists calculate nitrogen budgets to compare the rates at which usable nitrogen is supplied and removed. This balance influences the growth of plants and microbes that sustain food webs around the world.

“We study how nitrogen cycles on the planet, and we know that these processes of nitrogen removal occur,” said co-author David Valentine, the Norris Presidential Chair of Biogeochemistry and Liu’s postdoctoral advisor at UCSB. “But it’s very difficult to figure out how quickly that’s happening in a given environment, which makes it hard to work out the global nitrogen budget. Our new approach gives us a direct measure of that loss.”

Combined with information about water transport and how nitrogen gas accumulates, the measurements allow researchers to estimate nitrogen-loss rates at the ecosystem level. Extending those measurements across environments can link local estimates of nitrogen loss to regional and global budgets. Together, they offer an independent way to test whether nitrogen inputs and losses balance across the planet, and how that balance changes over time.

This story was written by Harrison Tasoff and Holly Ober at UCLA.

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Journal

Science

DOI

10.1126/science.aei0940

Article Title

Natural 15N15N abundances constrain fixed nitrogen loss

Article Publication Date

8-Oct-2026

 

UTIA researchers create hybrid materials to break down harmful farming chemicals

Nanocellulose with metal-organic frameworks prototype project wins USDA funding

University of Tennessee Institute of Agriculture

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Mi Li, associate professor in the Center for Renewable Carbon and the School of Natural Resources, left, and Jisoo Jeon, post-doctoral research associate, work in the lab to create special materials called Cello-MOFs, which are a combination of nanocellulose and metal-organic frameworks. Li received a $300,000 grant from the USDA to use nanotechnology and plant fibers to mitigate chemicals used on crop land.

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Credit: Photo by R. Lazarian, courtesy UTIA.

Nanotechnology using plant-based fibers could be the answer to detecting and cleaning up pesticides, fertilizers and other chemicals before they become harmful on the farm and in the environment.

A University of Tennessee Institute of Agriculture research project led by Mi Li, associate professor in the Center for Renewable Carbon and the School of Natural Resources, received $300,000 for two years from the USDA National Institute of Food and Agriculture’s Agriculture and Food Research Initiative nanotechnology program to create these prototype materials. The project also includes researchers from the University of Memphis and Auburn University.

Li and his lab focus on the conversion of plant-based resources into valuable chemicals, functional materials and polymers. His research combines wood chemistry, chemical synthesis, chemical engineering, polymer science and nanotechnology for green chemistry, circular carbon economy and a clean environment. His circular biorefining lab in the Center for Renewable Carbon taps renewable forestry and agricultural resources for value-added bioproducts.

Using chemicals like pesticides, fertilizers, and plant growth boosters in farming helps increase crop production, but it often leads to health hazards and environmental pollution. Mitigation of these chemicals can be a challenge because it is difficult to detect leftover chemicals in produce, soil and water and then turn them into harmless substances.

“The goal of my research is to mitigate environmental pollution by using renewable biomass feedstock and green chemistry technology,” Li said.

Through this project, Li and his team will create special materials called Cello-MOFs, which are a combination of nanocellulose, tiny plant-based fibers, with metal-organic frameworks, which are advanced porous and functional particles.

“These hybrids will work together to take in, detect, and break down harmful farming chemicals. The porous materials of MOFs are great for multiple tasks due to their large surface area and high functionality, but they’re brittle and small and hard to handle on their own. Pairing them with flexible, eco-friendly nanocellulose in paper or filter forms solves these problems, creating a powerful synergy,” he said.

The ultimate goal is to design and engineer Cello-MOFs in a tangible and portable pad-foam that can be used as a sponge in wastewater or on the surface of crops and produce. Upon taking in certain pollution chemicals, even in trace amounts, the sensitive Cello-MOFs will change their optical appearance that can be detected under UV light. By controlling the exposure to certain light, the Cello-MOFs will start degrading the adsorbed pollutants into, ideally, non-toxic compounds, or products with reduced toxicity.

The Cello-MOFs will be made of plant fibers, metals and linking molecules to make them effective at absorbing, sensing and decomposing pollutants. “It could lead to breakthrough technology for quick, on-the-spot monitoring and cleanup of chemical residues, while also advancing approaches to purify air, detect threats and protect the environment in agriculture and other fields,” he said.

The University of Tennessee Institute of Agriculture is comprised of the Herbert College of Agriculture, UT College of Veterinary Medicine, UT AgResearch and UT Extension. Through its land-grant mission of teaching, research and outreach, the Institute touches lives and provides Real. Life. Solutions. to Tennesseans and beyond. utia.tennessee.edu.

A researcher holds a vial of hybrid cellulose and metal-organic frameworks, or Cello-MOF, foams made from nanocellulose and functional MOFs.

Credit

Photo by R. Lazarian, courtesy UTIA.

 

Turning invasive plants into powerful filters for fluoride-contaminated water

Nano-magnesium oxide combined with plant-derived pyro-hydrochar achieves high fluoride adsorption while offering a new route for invasive biomass utilization

Shenyang Agricultural University Collaborative Journals

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Nano-MgO/pyro-hydrochar for enhancing adsorption of fluoride ion from aqueous solution: performance, influencing factors, and mechanisms

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Credit: Yao Tong, Donglin Wang, Lingqing Gu, Yujie Tai, Xianjie Tang, Xi Zhang, Rongdi An, Til Feike & Jiunian Guan

Excess fluoride in water is a persistent environmental and public health concern in many parts of the world. Now, researchers have developed a new plant-derived material that can capture fluoride efficiently while also creating value from invasive plant biomass.

A research team led by Jiunian Guan at Northeast Normal University has developed a nano-magnesium oxide modified pyro-hydrochar, or nMgO/Py-HyC, made from residues of the invasive plant Rhus typhina. The material achieved a maximum fluoride adsorption capacity of 469.64 milligrams per gram, outperforming the MgO-based adsorbents compared in the study.

“Our goal was to address two environmental challenges at the same time: fluoride contamination in water and the growing accumulation of invasive plant biomass,” said Jiunian Guan, corresponding author of the study. “By converting this biomass into a functional carbon material and combining it with nano-magnesium oxide, we created an adsorbent with strong fluoride-removal performance and promising environmental adaptability.”

Fluoride occurs naturally in groundwater, but industrial activities such as semiconductor manufacturing, glass production, electroplating, lithium refining, pesticide production and pharmaceutical manufacturing can also generate fluoride-containing wastewater. Excessive fluoride exposure can cause serious health problems, making effective treatment technologies important for both drinking water protection and industrial wastewater management.

The researchers first converted Rhus typhina biomass into hydrochar and then produced the magnesium-containing composite through a relatively simple pyrolysis process. The resulting porous carbon structure helped disperse nano-MgO particles and provided numerous sites where fluoride could be captured.

A major advantage was the material's ability to perform under different water conditions. Fluoride adsorption remained stable across a broad pH range from 5.0 to 11.0. Common coexisting ions such as nitrate and sulfate caused little interference, although high concentrations of bicarbonate reduced fluoride uptake.

Detailed material analyses revealed that fluoride was not captured through a single process. Instead, several mechanisms worked together, including electrostatic attraction, surface complexation, anion and ligand exchange, precipitation, and hydrogen bonding. Fluoride could interact directly with magnesium and form stable compounds such as MgF₂ and fluorine-containing magnesium hydroxide phases.

The researchers also observed a clear synergistic effect between the carbon support and nano-MgO. Under the same experimental conditions, the adsorption capacity of the combined material was substantially greater than the capacities of the two components considered separately. Its porous framework helped expose active magnesium sites and improved contact between fluoride ions and the adsorbent.

The study therefore points to a potential circular strategy: invasive plant residues can be transformed from an ecological management burden into a useful material for water remediation.

The authors note that further work is needed to evaluate the material under different real-world wastewater conditions and at engineering scale. Still, the findings provide a promising foundation for developing high-efficiency, low-carbon fluoride treatment technologies based on renewable biomass resources.

 

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Journal reference: Tong Y, Wang D, Gu L, Tai Y, Tang X, et al. 2026. Nano-MgO/pyro-hydrochar for enhancing adsorption of fluoride ion from aqueous solution: performance, influencing factors, and mechanisms. Biochar X 2: e023 doi: 10.48130/bchax-0026-0021  

https://www.maxapress.com/article/doi/10.48130/bchax-0026-0021  

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About the Journal: 

Biochar X (e-ISSN: 3070-1686) is an open access, online-only journal aims to transcend traditional disciplinary boundaries by providing a multidisciplinary platform for the exchange of cutting-edge research in both fundamental and applied aspects of biochar. The journal is dedicated to supporting the global biochar research community by offering an innovative, efficient, and professional outlet for sharing new findings and perspectives. Its core focus lies in the discovery of novel insights and the development of emerging applications in the rapidly growing field of biochar science. 

Follow us on Facebook, X, and Bluesky.  

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Journal

Biochar X

DOI

10.48130/bchax-0026-0021

Method of Research

Experimental study

Article Title

Nano-MgO/pyro-hydrochar for enhancing adsorption of fluoride ion from aqueous solution: performance, influencing factors, and mechanisms

 

Gaps in Awareness, Poor Communication Caused Tug, Barge, Workboat Collision

Former ferry Isabelle X being used for accommodations (TSB)

Published Oct 2, 2026 6:36 PM by The Maritime Executive

Marine investigators in Canada released a report outlining how gaps in situational awareness and a breakdown in communication caused a collision involving a tug, a barge, and a workboat in Squamish Harbor, British Columbia, in December 2024. The incident involved the tug Haisla Northwind, the barge BSG Lubricator, and the workboat Triton 1. It occurred in the marine safety zone of the Woodfibre LNG Project site.

The incident on December 18, 2024, occurred while the tug was pushing the barge on a scheduled run carrying provisions to the Isabelle X, a former ferry that was being used as a floating accommodation (floatel) for project workers, which was moored at the site. The barge collided with Triton 1, which was idling on standby, causing the workboat to capsize and sink.

The workboat’s operator, who was the only person on board, entered the water before being rescued by the workboat Roe 5 that was nearby and was treated for hypothermia. Only minor pollution was observed following the collision, with spill containment booms being deployed as a precaution. While no damage to the tug or barge was reported, the Triton 1 was not salvaged.

The Transportation Safety Board of Canada (TSB) has released its report on the incident, indicating that gaps in situational awareness and breakdown in communication were the main cause of the collision. The report shows that as Haisla Northwind pushed BSG Lubricator forward, visibility from the wheelhouse was obstructed by structures on board the tug and the barge, which reduced the tug master’s ability to visually detect the Triton 1 as it idled on the water.  

Due to the obstructed visibility from the wheelhouse, the master of Haisla Northwind was not aware of the workboat directly on his path. The investigators also established that bright lights from the construction site and nearby vessels also reflected off the water, creating glare that made the Triton 1’s navigation light difficult to distinguish from other lights in the area.

It was also established that Triton 1’s operator heard no arrival message on the VHF radio, did not expect any vessel to be approaching, and his attention was distracted by a cellphone call. Also, the operator is said to have expected the workboat’s navigation lights to make it visible to other vessels.

Built in 2018, the 110 gross tonnage Haisla Northwind was a multipurpose tug that supported various marine operations at the Woodfibre LNG project site, including anchor handling, crane operations, line handling, towing, and cargo stowage. She also transported wastewater, provisions, and equipment for workers. On the day of the incident, she had three crewmembers onboard. The 1964-built barge BSG Lubricator was mainly used to transport wastewater from, and provisions to, the Isabelle X. Built in 2021, the 7.6-meter Triton 1 did not have any fixed role at the site and was used as needed in various activities.

The investigation established that on the day of the incident at 1533, tug Haisla Northwind departed from Tymac Launch Station in Vancouver Harbor on a scheduled run to the floatel. She was pushing the barge BSG Lubricator, which was secured using a winch system on the tug’s bow. At around 1932, the two arrived at the project’s marine safety zone, approximately 600 meters south of the floatel. At this point, the tug’s speed was about 6.2 knots, with the master gradually reducing speed as she approached the ramp located at the floatel’s stern. The master relied primarily on visual navigation.

At about 1940, when the tug and barge were approximately 370 meters from the floatel, and while the deckhands were preparing to take their lookout positions, the master felt a sudden impact. The BSG Lubricator had struck the workboat Triton 1 that had been idling on standby. While initially the tug’s crew thought the barge had hit a submerged log, it soon became apparent that it was a workboat.

Investigators were able to establish that in the incident, gaps in situational awareness were a major factor in the collision. This is because the master of the tug was not aware that the workboat was in the path of the tug and the barge. Likewise, the operator of the workboat was unaware that the workboat was positioned in the direct path of the oncoming tug and barge. Another critical factor was visibility, as the view from the tug’s wheelhouse was obstructed by the crane located on the tug’s forward deck. Further, it was obstructed when pushing the barge with the four wastewater containers and one refrigerated container on the barge deck.

The investigation also found that operations at night posed further challenges to the tug master’s visibility. When approaching the floatel, bright lights from shore-based structures and nearby vessels caused significant light pollution, reflecting off the water and creating glare. This made it difficult for the tug master to distinguish the navigation lights of other vessels that may have been in the tug and barge’s path.  

TSB said that following the collision, organizations involved have since taken safety actions, including strengthening lookout and communication procedures, installing additional vessel-tracking and visibility equipment, and introducing new marine safety plans. Other measures include restricting all barge movements to daylight hours and improving coordination among vessels operating within the marine safety zone.
 

 

Palermo, first coffee grown and harvested in Italy: warmer climate is changing farming

Copyright AP Photo/Andre Penner

By Gabriele Barbati

Published on 02/10/2026 - EURONEWS

Rising temperatures now allow coffee to be grown in Italy. In Sicily, the Morettino family has completed its first harvest, showing how climate change is reshaping crops worldwide.

A plantation on the outskirts of Palermo has for the first time produced Arabica coffee beans grown and harvested entirely in Italy. The result, achieved on the Morettino family estate, has been made possible by climate change, which has effectively brought tropical temperatures to southern Italy.

While global warming had already enabled southern England to produce champagne-style sparkling wine, pushing the traditional growing areas of France and northern Italy further north, the jump made by coffee from equatorial zones to the Mediterranean is clearly even greater.

As the daily newspaper La Stampa reported on Thursday (source in Italian), the Sicilian plantation in the San Lorenzo ai Colli area, a few hundred metres above sea level, is currently producing around 100 kilograms of drupes (the fruit of the coffee plant, also known as cherries), which yield just over 15 kilograms of roasted beans.

The project, which involves the University and the Botanical Garden of Palermo (source in Italian) in studying how tropical crops adapt to the new Mediterranean climate, is still far from large-scale commercial production in terms of volume, but it already has considerable scientific and symbolic value.

Typical coffee makers used in Italy, on display at a 2013 exhibition in Milan by historic manufacturer Bialetti (AP Photo/Luca Bruno)

Where coffee is grown: the world’s main producing countries

Traditionally, coffee is grown in the planet’s tropical and equatorial regions, where high temperatures, humidity and steady rainfall favour its growth.

For this reason, the world’s main producers and exporters are largely concentrated in Latin America, Africa and Asia, with the Arabica variety, which delivers higher quality, grown at higher altitudes than Robusta.

The leading producer countries include Brazil, Colombia, Peru and Costa Rica in Latin America; Ethiopia, Uganda, Kenya and Tanzania in Africa; and Vietnam and Indonesia in Asia.

According to the promoters of the initiative, the coffee produced in Palermo develops distinctive aromatic notes reminiscent of raisins, a feature that sets it apart from beans grown in traditional coffee-growing regions.

Before the Morettino family’s venture, a local farm had already grown coffee entirely in greenhouses (source in Italian) in Terrasini, also in the Palermo area.

Similar experiments have been attempted in various forms elsewhere in southern Europe.

In Spain, particularly in the province of Granada, experimental projects have been launched to test the resilience of the plants, with results quite different from those in Gran Canaria where, thanks to its more southerly latitude, coffee has been grown since the 19th century, taking advantage of the fertility and humidity of volcanic soils.

On the Azores islands in Portugal, where numerous private plantations have been reported that benefit from the mild climate, the archipelago marks one of the northernmost points where coffee is grown.

Former Italian prime minister and ECB president Mario Draghi sips an espresso during a break in proceedings in the Chamber of Deputies (18 February 2021) (AP Photo/Andrew Medichini)

How coffee consumption in Italy has changed

The growing interest in niche products such as the Sicilian coffee comes in a context in which Italy is the EU’s leading producer of roasted coffee, with over 400 tonnes produced in 2025.

The national coffee industry, although it relies on importing raw material from other producer countries (that is, unroasted beans, or "green coffee"), includes around a thousand roasters and generates an annual turnover of 5.9 billion euros.

The prospect of local cultivation, made possible by global warming, which is unfortunately also bringing more natural disasters, is in step with Italian consumption patterns, which remain robust and are growing, according to several studies published on 1 October to mark International Coffee Day.

According to a survey by AstraRicerche in partnership with the Segafredo brand, 82.6% of Italians consider the quality of the raw material decisive, while 71.8% pay attention to aromatic characteristics and 51.5% want to know the product’s origin and its journey along the supply chain.

Another survey, carried out by the Italian Coffee Committee of Unione Italiana Food and by Altroconsumo on more than 1,200 consumers, shows that three out of four Italians drink coffee regularly and almost one in two see it as one of the symbols of the country’s culture and lifestyle, on a par with pasta.

Among those who drink espresso, 83% have it every day, at home and at the bar, either with a moka pot or with modern capsule machines, which are now neck and neck in people’s habits.

Any commercial prospects must of course be weighed against environmental sustainability when growing coffee outside its traditional areas of origin.

Processing the beans after harvest can require between 50 and 200 litres of water for every kilogram of green coffee and produces wastewater which, if not properly treated, can affect local ecosystems.

And if, instead of the tropical rains that have always sustained coffee plantations, growing moves to areas where seasonal drought is becoming endemic, it becomes essential to match the agricultural challenge of coffee with a technological one, cutting the amount of water needed to grow and process the crop.