New insights into biochar reveal how to better capture phosphorus and protect water systems
image:
Different adsorption of organic phosphorus on calcium modified biochar: comprehensive insights from molecular levels
view moreCredit: Ning Wang, Liangjie Tang, Xiaohui Zhang, Dongtan Yao, Xiaolei Sun, Alain Mollier, Xiaolong Lin & Xiaoqian Jiang
A new study uncovers how specially engineered biochar can more effectively capture organic phosphorus, offering a promising solution to reduce nutrient pollution while improving sustainable phosphorus use in agriculture.
Phosphorus is essential for crop growth, but its overuse has led to widespread environmental problems. When excess phosphorus leaches into rivers and lakes, it can trigger harmful algal blooms and degrade water quality. While scientists have long explored biochar as a tool to retain phosphorus in soils, most research has focused on inorganic forms, leaving a major knowledge gap in how biochar interacts with organic phosphorus compounds.
Now, researchers have developed a calcium-modified biochar and revealed, at the molecular level, how it interacts with different types of organic phosphorus. Their findings provide a clearer roadmap for designing more effective materials to control phosphorus loss and enhance nutrient recycling.
“We wanted to understand not just how much phosphorus biochar can adsorb, but why different molecules behave differently,” said the study’s corresponding author. “By uncovering the mechanisms at the molecular scale, we can better design biochar materials for real-world environmental applications.”
The team produced the modified biochar using agricultural waste materials, combining corn straw with eggshells to introduce calcium-rich active sites. These calcium components significantly enhanced the material’s ability to capture organic phosphorus across a range of environmental conditions.
Experiments showed that the biochar exhibited strong adsorption performance for several key organic phosphorus compounds, including inositol hexaphosphate, glycerophosphate, glucose-6-phosphate, and ATP. Among them, inositol hexaphosphate demonstrated the highest adsorption capacity, reaching over 290 milligrams of phosphorus per gram of biochar.
The study revealed that different molecular structures led to distinct adsorption mechanisms. For most compounds, calcium-driven chemical precipitation dominated, forming stable calcium-phosphate complexes on the biochar surface. In contrast, ATP adsorption relied more on hydrogen bonding and electrostatic interactions.
Importantly, the researchers found that both phosphate groups and carbon chain structures play key roles in determining how organic phosphorus interacts with biochar. Molecules with multiple reactive phosphate groups were able to bind more strongly and resist desorption, reducing the risk of phosphorus release back into the environment.
Advanced analytical techniques and computational modeling further showed that the adsorption process is not governed by a single mechanism. Instead, it involves a combination of chemical reactions, surface interactions, and molecular-level coordination, all influenced by the structure of the phosphorus compound.
“Our results highlight that molecular structure matters,” the authors explained. “Even small differences in functional groups or charge distribution can significantly affect how phosphorus is retained or released.”
Beyond improving phosphorus capture, the modified biochar also demonstrated stability under varying environmental conditions such as changes in pH and the presence of competing ions. This resilience is critical for real-world applications in soils and wastewater systems.
The findings have important implications for sustainable agriculture and environmental protection. By enhancing phosphorus retention in soils, such materials could reduce fertilizer losses, improve nutrient efficiency, and help mitigate water pollution.
More broadly, the study advances the understanding of how biochar can be engineered at the molecular level to target specific contaminants. As global phosphorus resources become increasingly limited, technologies that enable efficient recycling and recovery will play a vital role in future food systems.
“This work bridges the gap between material design and environmental function,” the researchers said. “It opens new opportunities for using biochar not only as a soil amendment, but as a precision tool for managing nutrients and protecting ecosystems.”
===
Journal Reference: Wang, N., Tang, L., Zhang, X. et al. Different adsorption of organic phosphorus on calcium modified biochar: comprehensive insights from molecular levels. Biochar 8, 47 (2026).
https://doi.org/10.1007/s42773-025-00562-z
===
About Biochar
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
Follow us on Facebook, X, and Bluesky.
Journal
Biochar
Method of Research
Experimental study
Article Title
Different adsorption of organic phosphorus on calcium modified biochar: comprehensive insights from molecular levels
New biochar-based technology boosts antibiotic removal from water using low-energy ultrasound
Biochar Editorial Office, Shenyang Agricultural University
image:
Sustainable removals of antibiotics via biochar-enhanced ultrasound cavitation effect: synergy of carbon nanotube bonded biochar@Fe3C composite and low frequency energy efficiency
view moreCredit: Ao Wang, Nan Zhao, Lei He, Ye Xiao, Chuanfang Zhao, Siyuan Guo, Xiang Liu, Weihua Zhang, Kunyuan Liu & Rongliang Qiu
Researchers have developed a new carbon-based material that dramatically improves the removal of persistent antibiotics from water, offering a promising and energy-efficient solution to a growing environmental challenge.
Antibiotics such as enrofloxacin and amoxicillin are widely used in human and veterinary medicine, but their residues often accumulate in wastewater and natural environments. These compounds are difficult to degrade and can contribute to antibiotic resistance and ecological risks. Conventional treatment methods, including ultrasound alone, often require high energy input but still achieve limited removal efficiency.
In a new study, scientists designed a novel composite material that combines biochar, carbon nanotubes, and iron carbide into a single structure. When paired with low-frequency ultrasound, the material significantly accelerates the breakdown of antibiotics in water.
“Our goal was to create a material that not only adsorbs antibiotics but also actively promotes their degradation under mild conditions,” said one of the study’s lead authors. “By integrating biochar with carbon nanotubes and iron, we were able to enhance both the efficiency and sustainability of the process.”
The newly developed material, referred to as a biochar-based solid cavitation material, works by amplifying the physical and chemical effects generated during ultrasound treatment. When ultrasound waves pass through water, they create tiny bubbles that rapidly collapse, producing localized high temperatures and reactive species capable of breaking down pollutants. However, this process is typically inefficient at low frequencies.
The researchers found that their material significantly enhances this cavitation effect. The biochar component increases hydrophobicity and surface stability, allowing more cavitation bubbles to form and persist on the material surface. At the same time, carbon nanotubes and iron sites facilitate chemical reactions that generate reactive oxygen species, which further degrade antibiotic molecules.
As a result, the system achieved up to 15 times higher removal rates compared to conventional materials. More than 90 percent of both enrofloxacin and amoxicillin were removed within several hours under low-frequency ultrasound, while requiring substantially less energy than traditional approaches.
Importantly, the study revealed that antibiotic removal occurs through a dual mechanism. First, the pollutants are adsorbed onto the material surface through hydrophobic interactions and molecular bonding. Then, they are degraded by reactive species generated during cavitation. This combination of adsorption and degradation ensures more complete and efficient treatment.
“We observed a strong synergy between the material and ultrasound,” the authors explained. “The material improves bubble formation and stability, while ultrasound enhances dispersion and prevents surface deactivation, leading to sustained performance.”
The technology also demonstrated robustness across a wide range of pH conditions and maintained high efficiency after multiple reuse cycles. Tests in real water samples showed only a slight reduction in performance, indicating strong potential for practical applications.
Beyond its effectiveness, the system offers a more sustainable alternative to existing treatment methods. By operating at lower ultrasound frequencies and energy inputs, it reduces operational costs while maintaining high removal efficiency.
The findings provide new insights into how engineered carbon materials can be used to control cavitation processes and improve water treatment technologies. The researchers believe that this approach could be extended to remove other persistent organic pollutants from wastewater.
“This work opens up new possibilities for designing low-cost and energy-efficient materials for environmental remediation,” the authors said. “It represents a step forward in addressing antibiotic pollution and protecting water quality.”
===
Journal Reference: Wang, A., Zhao, N., He, L. et al. Sustainable removals of antibiotics via biochar-enhanced ultrasound cavitation effect: synergy of carbon nanotube bonded biochar@Fe3C composite and low frequency energy efficiency. Biochar 8, 46 (2026).
https://doi.org/10.1007/s42773-025-00551-2
===
About Biochar
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
Follow us on Facebook, X, and Bluesky.
Journal
Biochar
Method of Research
Experimental study
Article Title
Sustainable removals of antibiotics via biochar-enhanced ultrasound cavitation effect: synergy of carbon nanotube bonded biochar@Fe3C composite and low frequency energy efficiency
Turning waste into a solution: micro-nano bone biochar boosts rice yield and cuts toxic cadmium
Biochar Editorial Office, Shenyang Agricultural University
image:
Micro-nanoscale bone char alters Cd accumulation and rhizosphere functional genes to enhance rice yield and quality
view moreCredit: Anqi Liang, Yi Hao, Zeyu Cai, Weitao Wu, Xinxin Xu, Weili Jia, Yini Cao, Lanfang Han, Luca Pagano, Marta Marmiroli, Elena Maestri, Nelson Marmiroli, Jason C. White, Chuanxin Ma & Baoshan Xing
Researchers have developed a novel soil amendment made from animal bone waste that can both increase rice production and significantly reduce the accumulation of toxic cadmium in edible grains, offering a promising strategy for safer and more sustainable agriculture.
Cadmium contamination in agricultural soils is a growing global concern, particularly for rice, a staple food for more than half of the world’s population. Because rice readily absorbs cadmium, even low levels in soil can lead to dangerous concentrations in grains, posing risks to food safety and human health. Finding effective and scalable solutions to reduce cadmium uptake while maintaining crop productivity remains a major challenge.
In a new study, scientists investigated the use of micro-nanoscale bone char, a biochar derived from waste pork bones and processed into extremely fine particles. The material was produced through controlled heating and mechanical milling, resulting in a highly reactive amendment with a large surface area and abundant functional groups.
“We aimed to develop a strategy that not only reduces cadmium risks but also improves crop performance and soil health,” said the study’s corresponding author. “Using waste-derived materials makes this approach both environmentally and economically attractive.”
The research team conducted a 140 day full life cycle experiment growing rice in cadmium contaminated soil under greenhouse conditions. Their results show that the application of micro-nano bone char had striking benefits.
Rice yield increased by nearly 50 percent under one treatment, while the number of productive tillers rose by more than 20 percent. At the same time, cadmium accumulation in polished rice grains dropped by up to 68 percent compared to untreated contaminated soil. This reduction brings cadmium levels much closer to food safety standards.
The material works through multiple mechanisms. It binds cadmium in the soil, reducing its bioavailability and limiting its transport into plant tissues. It also alters soil chemistry, including increasing pH and enhancing nutrient availability, particularly phosphorus. These changes create a more favorable environment for plant growth.
In addition, advanced metagenomic analyses revealed that the amendment reshaped the soil microbial community. Beneficial microorganisms involved in carbon, nitrogen, and phosphorus cycling became more abundant, while genes associated with phosphorus availability were significantly enhanced. These microbial shifts further support plant nutrition and soil resilience.
The researchers also found that the treatment influenced the metabolic composition of rice grains. It slowed the breakdown of key carbohydrates and amino acids, suggesting potential improvements in grain nutritional quality.
Importantly, the raw material used to produce the biochar is widely available as an agricultural and food industry byproduct. Converting bone waste into a high value soil amendment supports circular economy principles while addressing environmental challenges.
A preliminary cost benefit analysis suggests that the approach is economically viable. Although there are costs associated with producing and applying the material, the increase in yield and the reduction in contaminated grain losses can generate substantial net benefits for farmers.
“Our findings demonstrate that micro-nano bone char can serve as a powerful tool for managing contaminated soils,” the authors noted. “It offers a pathway to safer food production while improving sustainability in agriculture.”
The study highlights the potential of combining waste recycling, nanotechnology, and soil science to tackle one of the most pressing issues in global food security. Further research and field scale applications could help bring this technology closer to real world implementation.
===
Journal Reference: Liang, A., Hao, Y., Cai, Z. et al. Micro-nanoscale bone char alters Cd accumulation and rhizosphere functional genes to enhance rice yield and quality. Biochar 8, 45 (2026).
https://doi.org/10.1007/s42773-025-00548-x
===
About Biochar
Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field.
Follow us on Facebook, X, and Bluesky.
Journal
Biochar
Method of Research
Experimental study
Article Title
Micro-nanoscale bone char alters Cd accumulation and rhizosphere functional genes to enhance rice yield and quality
Biochar’s climate promise depends on soil type: Cuts N₂O in dry fields but boosts it in rice paddies
Maximum Academic Press
image:
Dynamics of (a) soil N2O production rate, and (b) cumulative soil N2O emission, and (c) inorganic nitrogen concentrations after biochar or CaO addition in two studied soils. Error bars indicate the standard deviations of the means (n = 3). Different capital letters indicate significant differences between BC treatments in the same soil (p < 0.05); different lowercase letters indicate significant differences between CaO treatments in the same soil (p < 0.05). * Indicate statistical significance at p < 0.05. BC, Biochar; CaO, lime; US, upland soil; PS, paddy soil.
view moreCredit: The authors
By tracing the exact microbial pathways responsible for N₂O production, the scientists reveal why the same soil amendment produces opposite climate outcomes under different land uses.
Nitrous oxide is a potent greenhouse gas with a global warming potential 265 times that of carbon dioxide over 100 years and is now the leading ozone-depleting substance in the 21st century. Agricultural nitrogen fertilization is its dominant source, particularly in acidic soils common in humid subtropical regions. Biochar has been widely promoted as a solution: it can raise soil pH, alter microbial processes, and in many cases reduce N₂O emissions. However, previous studies have reported inconsistent results, especially in strongly acidic soils and under different water regimes. A key unresolved question has been whether biochar’s mitigation effect arises simply from pH changes—similar to liming—or from deeper microbial mechanisms that vary across land-use types.
A study (DOI: 10.48130/nc-0025-0021) published in Nitrogen Cycling on 22 January 2026 by Jinbo Zhang’s team, Hainan University, highlights the need for land-use-specific mitigation strategies and offers a mechanistic roadmap for designing smarter, climate-resilient soil management practices.
Using a controlled short-term incubation experiment combined with natural-abundance isotopic tracing and high-resolution molecular analyses, the researchers quantified N₂O fluxes and partitioned their microbial sources in acidic upland and flooded paddy soils amended with graded biochar or CaO. N₂O emissions were monitored over 96 hours following urea addition, and isotopic signatures (δ¹⁵N_bulk, δ¹⁵N_SP, and δ¹⁸O) were integrated into a Bayesian FRAME model to apportion contributions from bacterial denitrification (bD), fungal denitrification (fD), nitrifier denitrification (nD), autotrophic nitrification (Ni), and heterotrophic nitrification (hN). Parallel measurements of soil physicochemical properties, nitrogen species, and functional gene abundances (including amoA, nirS, nirK, and nosZII) were conducted using qPCR and high-throughput sequencing. The results revealed sharply contrasting responses between land-use types. In upland soil, biochar significantly reduced cumulative N₂O emissions relative to the control and CaO treatments, with isotopic modeling showing marked declines in bD- and fD-derived N₂O. This reduction corresponded with decreased abundance of high N₂O-producing fungi such as Chaetomium and a substantial increase in the nosZII/(N₂O-producing genes) ratio, indicating enhanced microbial reduction of N₂O to N₂. Biochar also lowered residual N₂O fractions and increased total N₂ production, confirming more complete denitrification. In contrast, in flooded paddy soil, biochar dramatically increased cumulative N₂O emissions—by more than five- to fourteen-fold at higher application rates. All five microbial pathways contributed nearly equally, and their absolute N₂O production rates were amplified following biochar addition. Gene abundances linked to nitrification and denitrification increased, and high soil organic carbon and nitrogen availability appeared to stimulate multiple N₂O-producing processes simultaneously. Collectively, the pathway-based isotope and molecular evidence demonstrates that biochar suppresses denitrification-driven N₂O in upland soil but enhances multi-pathway N₂O production in flooded paddy soil.
Overall, the study reveals that biochar’s climate benefits are not universal but depend critically on land-use type and underlying microbial ecology. By combining isotopic pathway partitioning with molecular analyses, the research demonstrates that upland mitigation arises from targeted suppression of N₂O-producing fungi and enhanced N₂O reduction, whereas in flooded systems, biochar can stimulate multiple production routes simultaneously. These findings underscore the importance of mechanistic, pathway-level assessments before scaling up biochar applications and point toward precision soil manageme.
###
References
DOI
Original Souce URL
https://doi.org/10.48130/nc-0025-0021
Funding information
This work was supported by the Hainan Provincial Natural Science Foundation of China (Grant No. 425CXTD606), the National Natural Science Foundation for Excellent Youth Science Foundation of China (Grant No. RZ2400002277), and College initial funding (Grant No. 1677772342Y).
About Nitrogen Cycling
Nitrogen Cycling is a multidisciplinary platform for communicating advances in fundamental and applied research on the nitrogen cycle. It is dedicated to serving as an innovative, efficient, and professional platform for researchers in the field of nitrogen cycling worldwide to deliver findings from this rapidly expanding field of science.
Method of Research
Experimental study
Subject of Research
Not applicable
Article Title
Biochar's contrasting effects on N2O emissions in acidic upland and flooded paddy soils
