Biochar reshapes ant societies, revealing hidden ecological trade-offs in soil restoration
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Biochar application enhances ant (Formica japonica) ecological functions as indicated by their social behaviors
view moreCredit: Sha Liu, Danling Xiong, Liang Zeng, Wei Du, Yang Liu, Christian E. W. Steinberg, Bo Pan, Shu Tao & Baoshan Xing
A new study shows that biochar, widely promoted as a climate-smart soil amendment, can significantly reshape the social lives of ants, with cascading effects on ecosystem functioning. The findings highlight both the promise and the risks of using biochar in large-scale land restoration.
Soil ecosystems depend not only on chemistry and microbes, but also on animals that engineer the environment. Ants, in particular, play a central role in soil aeration, nutrient cycling, and community regulation. Yet until now, little was known about how biochar affects their behavior and ecological functions.
“Our results show that biochar does not simply improve soil conditions. It also changes how soil animals behave and interact, which can amplify or undermine ecosystem recovery,” said the study’s lead author.
The research, based on controlled experiments with the ant species Formica japonica, tested four biochar application rates ranging from 0 to 10 %. The results reveal a clear dose-dependent pattern.
At moderate levels, biochar significantly enhanced multiple aspects of ant performance. Ants exposed to 2.5 to 5 % biochar showed a 73.4 % increase in nest site selection specificity, a 2.8-fold increase in nest complexity, and a doubling of foraging efficiency. Social recognition accuracy also improved by 3.5 times, indicating stronger colony cohesion.
These behavioral changes translated into stronger ecological functions. More complex nests improved soil structure and aeration, while faster and more efficient foraging likely enhanced nutrient redistribution. Increased cooperation and territorial defense suggested more stable and resilient colonies.
The researchers link these improvements to moderate shifts in soil properties. Biochar slightly increased soil pH and organic matter, creating conditions that made excavation easier and improved sensory signaling among ants.
However, the benefits did not continue at higher doses.
At 10 % biochar, ant survival dropped sharply to around 55 to 60 % over ten days. Behavioral performance also declined. Foraging slowed dramatically, nest construction weakened, and social interactions became less effective.
The study points to two key stressors behind these negative effects. First, high biochar concentrations increased soil alkalinity beyond the optimal range for ants. Second, they introduced environmentally persistent free radicals, which are known to induce oxidative stress and neurotoxicity in soil organisms.
“These findings suggest a classic hormetic response, where low doses stimulate biological activity but high doses become harmful,” the authors explained.
Importantly, the research highlights that soil restoration strategies must consider biological complexity, not just chemical improvements. Ants and other soil fauna act as ecosystem engineers, and their behavior can determine whether soil interventions succeed or fail.
The study also raises broader ecological questions. Changes in ant aggression, cooperation, and recognition could alter species interactions, pest control, and biodiversity patterns in treated soils.
“Biochar has great potential, but its application must be carefully optimized. Too much can disrupt the very biological systems we aim to restore,” the authors noted.
As global efforts intensify to combat soil degradation and climate change, the findings provide a timely reminder. Sustainable solutions must balance physical, chemical, and biological dimensions of ecosystems.
This research offers a new perspective by linking soil amendments to animal behavior and ecosystem function, opening the door to more biologically informed approaches to land management.
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Journal Reference: Liu, S., Xiong, D., Zeng, L. et al. Biochar application enhances ant (Formica japonica) ecological functions as indicated by their social behaviors. Biochar 8, 77 (2026).
https://doi.org/10.1007/s42773-026-00594-z
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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.
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Journal
Biochar
Method of Research
Experimental study
Article Title
Biochar application enhances ant (Formica japonica) ecological functions as indicated by their social behaviors
Engineered biochar unlocks soil’s natural chemistry to break down antibiotic pollution
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In-situ and long-enduring oxidation of SMX by Fe-modified biochar activated O2 in soil: bridging Fe-redox cycling and electron transfer modulation
view moreCredit: Hongying Du, Lei Zhang, Wenbo Liu, Yuyang Xie, Xueyan Hou, Junkang Guo & Qixing Zhou
A new study reveals how an advanced iron-modified biochar can harness the natural chemistry of soils to break down persistent antibiotic contaminants, offering a sustainable and chemical-free approach to environmental remediation.
Antibiotics such as sulfamethoxazole are widely detected in agricultural soils due to manure application and wastewater reuse. These compounds can persist in the environment, contributing to antibiotic resistance and ecosystem risks. Traditional treatment methods often rely on strong chemical oxidants, which can disrupt soil health and are not well suited for low-concentration contaminants.
Researchers have now developed a novel iron-modified biochar that activates naturally occurring oxygen in soils to generate highly reactive hydroxyl radicals, enabling the in situ degradation of contaminants without external chemical inputs. The findings are reported in Biochar.
“This work shows that we can activate the soil’s own oxidative capacity rather than relying on added chemicals,” said the study’s corresponding author. “By engineering biochar to regulate iron cycling and electron transfer, we create a self-sustaining system for pollutant removal.”
The innovation lies in designing biochar that functions simultaneously as an “electron highway” and a “redox regulator.” By carefully controlling iron species and the carbon structure, the material enhances the cycling between Fe(II) and Fe(III), a key process that drives the production of hydroxyl radicals. These radicals are among the most powerful oxidants in nature and can break down complex organic pollutants.
Laboratory and soil incubation experiments showed that the optimized material increased hydroxyl radical production by up to 4.2 times compared to untreated soil, reaching levels as high as 881.6 micromolar. Even under field conditions, the enhancement remained significant at more than threefold.
This increase in reactive species translated into effective pollutant removal. The degradation of sulfamethoxazole reached over 80 percent in treated soils. The breakdown occurred through multiple pathways, including ring opening, hydroxylation, and bond cleavage, ultimately reducing the toxicity of the compound.
Importantly, the system operates through a dual mechanism. The biochar directly catalyzes reactions on its surface, while also amplifying natural soil processes by stimulating iron redox cycling. This combined effect enables continuous production of reactive species over time.
The study also highlights the role of soil microbes. Microbial activity contributed nearly 40 percent of hydroxyl radical generation, indicating a strong interaction between biological and chemical processes. The biochar amendment increased microbial diversity and enriched bacteria involved in iron cycling, further supporting sustained pollutant degradation.
Beyond contaminant removal, the approach offers additional environmental benefits. The transformation of pollutants produced less toxic intermediates, and plant growth tests showed improved seed germination and biomass in treated soils compared to contaminated controls. The system also promoted the formation of more stable soil organic matter, suggesting potential co-benefits for soil health and carbon management.
Unlike conventional advanced oxidation processes, which often require added chemicals such as hydrogen peroxide or persulfate, this method relies on abundant molecular oxygen and naturally occurring soil minerals. This makes it more environmentally friendly and potentially scalable for agricultural applications.
The researchers describe the approach as a “waste-to-remediation” strategy, as the biochar is produced from biomass residues. By turning agricultural waste into a functional material, the technology aligns with circular economy principles while addressing pressing environmental challenges.
Overall, the study provides a new framework for designing biochar-based materials that integrate chemical, electrochemical, and biological processes. By bridging iron redox cycling and electron transfer, the work opens new possibilities for sustainable soil remediation and the mitigation of emerging contaminants.
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Journal Reference: Du, H., Zhang, L., Liu, W. et al. In-situ and long-enduring oxidation of SMX by Fe-modified biochar activated O2 in soil: bridging Fe-redox cycling and electron transfer modulation. Biochar 8, 76 (2026).
https://doi.org/10.1007/s42773-026-00585-0
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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
In-situ and long-enduring oxidation of SMX by Fe-modified biochar activated O2 in soil: bridging Fe-redox cycling and electron transfer modulation
Tuning biochar temperature unlocks major nitrogen savings in food waste composting
Biochar Editorial Office, Shenyang Agricultural University
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Nitrogen conservation by hardwood biochar during food waste digestate composting: pyrolytic temperature dictates microbial mechanisms
view moreCredit: Dongyi Li, Jun Zhou, Jialin Liang, Qiuxiang Xu, Jiayu Zhang, Wenhua Xue & Jonathan W. C. Wong
Food waste is often seen as a problem, but it also represents a valuable resource in the transition toward a circular bioeconomy. A new study shows that a simple adjustment in how biochar is produced can dramatically improve the efficiency of composting food waste digestate, cutting nitrogen loss nearly in half while reducing harmful emissions.
Researchers have discovered that the temperature used to produce biochar plays a decisive role in how effectively it conserves nitrogen during composting. By carefully selecting this temperature, they were able to optimize both environmental performance and compost quality.
“Biochar is not just a passive material that absorbs gases,” said the study’s corresponding author. “It actively shapes the microbial community in compost, and that determines how nitrogen is retained or lost.”
Food waste digestate, a byproduct of anaerobic digestion, is rich in nutrients but difficult to manage. During composting, large amounts of nitrogen are lost as ammonia and nitrous oxide. Ammonia contributes to air pollution, while nitrous oxide is a potent greenhouse gas. These losses reduce the fertilizer value of compost and create environmental concerns.
To address this challenge, the research team produced hardwood biochar at three different temperatures, 300 degrees Celsius, 400 degrees Celsius, and 800 degrees Celsius. They then added the biochar to composting systems and tracked nitrogen transformations, gas emissions, and microbial activity.
The results revealed a clear trade-off. Biochar produced at lower temperature was highly effective at reducing ammonia emissions, cutting them by more than 39 percent. This was linked to the presence of oxygen-containing functional groups that enhance ammonium adsorption and stimulate microbial nitrification.
In contrast, high-temperature biochar performed best at reducing nitrous oxide emissions, achieving a reduction of nearly 48 percent. Its highly porous structure improved oxygen diffusion in compost, suppressing microbial processes that generate nitrous oxide.
However, neither extreme provided the best overall outcome. The breakthrough came with biochar produced at 400 degrees Celsius, which achieved the optimal balance between these competing processes. This treatment reduced total nitrogen loss by 46.3 percent compared to the control, the highest performance among all tested conditions.
According to the study, this balance arises because medium-temperature biochar simultaneously supports beneficial microbial communities and provides sufficient adsorption capacity. It enhances nitrification while avoiding excessive stimulation of incomplete denitrification, which can lead to nitrous oxide production.
The findings also highlight the importance of microbial ecology in composting systems. Biochar was shown to act as a habitat that selectively enriches key nitrogen-cycling microorganisms, including ammonia-oxidizing bacteria and nitrite-oxidizing bacteria. These microbes play a central role in converting nitrogen into stable forms that remain in the compost.
Beyond improving compost quality, the approach offers broader environmental benefits. Reducing nitrogen loss helps retain nutrients in agricultural systems, while lowering greenhouse gas emissions supports climate mitigation efforts.
The researchers note that biochar produced at moderate temperatures is also more practical from an energy and economic perspective, making it suitable for large-scale applications.
“This work provides a clear framework for designing biochar-based strategies to improve composting,” the author said. “By tuning pyrolysis temperature, we can steer microbial processes and achieve both environmental and agronomic benefits.”
The study provides new insights into how engineered carbon materials can be used to enhance sustainable waste management. Future research will focus on scaling up the approach and further refining biochar properties to target specific environmental outcomes.
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Journal Reference: Li, D., Zhou, J., Liang, J. et al. Nitrogen conservation by hardwood biochar during food waste digestate composting: pyrolytic temperature dictates microbial mechanisms. Biochar 8, 75 (2026).
https://doi.org/10.1007/s42773-026-00588-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
Nitrogen conservation by hardwood biochar during food waste digestate composting: pyrolytic temperature dictates microbial mechanisms
Magnetic biochar gel offers breakthrough solution for arsenic and antimony contamination in rice fields
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Magnetic silicon-enriched biochar for effectively mitigating As and Sb in soil-rice continuum: from integrated geochemical, microbial, and phytophysiological insights
view moreCredit: Yurong Gao, Hanbo Chen, Fenglin Wang, Jiayi Li, Zheng Fang, Xiaokai Zhang, Xing Yang, Jin Wang, Juan Liu, Caibin Li & Hailong Wang
A newly developed magnetic biochar material could help farmers grow safer rice in soils contaminated with toxic elements, while also improving crop yields and soil health.
Researchers have created a silicon-rich magnetic biochar gel that effectively reduces the uptake of arsenic and antimony in rice plants, two hazardous metalloids commonly found together in polluted agricultural soils. These contaminants pose serious risks to food safety and human health, particularly in rice-based diets.
“Managing arsenic and antimony together in flooded rice soils has long been a major challenge,” said one of the study’s authors. “Our work shows that this new biochar material can simultaneously stabilize both contaminants while supporting plant growth.”
The study introduces a novel material called FeRBG, a magnetic biochar gel produced from rice husk waste, iron oxides, and graphene. This combination forms a three-dimensional porous structure with enhanced adsorption capacity and chemical reactivity.
In greenhouse experiments using contaminated paddy soil, the new material significantly reduced the bioavailable forms of arsenic and antimony in soil. Compared to untreated soil, the biochar gel decreased extractable antimony and arsenic by over 20 percent. More importantly, it reduced their accumulation in rice grains by 16.1 percent and 34.0 percent, respectively.
The reduction in grain arsenic levels brought concentrations below national food safety limits, highlighting the material’s potential for real-world agricultural applications.
The researchers found that the biochar gel works through multiple mechanisms. Iron components form strong chemical bonds with arsenic and antimony, locking them into stable mineral forms. At the same time, the porous structure provides abundant sites for adsorption, while graphene enhances electron transfer and stability. Together, these features convert mobile contaminants into less bioavailable forms in the soil.
Beyond contaminant immobilization, the material also improved plant health. Rice plants grown in treated soil developed stronger root systems, with increases in root length, surface area, and root tip numbers. These changes enhance nutrient uptake and resilience under stress conditions.
The study also revealed that the biochar amendment reshaped soil microbial communities. Beneficial bacteria associated with nutrient cycling and stress tolerance became more abundant, while the overall diversity of soil microbes increased. These biological shifts are linked to reduced metal stress and improved soil conditions.
In addition, treated plants showed lower levels of physiological stress. Indicators such as proline content decreased, suggesting reduced oxidative damage, while antioxidant enzyme activity increased, helping plants better cope with environmental stress.
The researchers used advanced modeling to understand how these effects are connected. Their analysis showed that reducing arsenic availability in soil was the most important factor influencing plant growth and yield. By stabilizing contaminants and improving soil chemistry, the biochar gel created a more favorable environment for rice development.
This work highlights a promising strategy for addressing one of agriculture’s most persistent contamination problems. By combining waste-derived materials with advanced engineering, the approach supports both environmental remediation and sustainable food production.
The authors note that further field studies are needed to confirm long-term performance under real farming conditions. However, the results demonstrate strong potential for scaling up this technology in regions affected by metalloid pollution.
As global concerns about soil contamination and food safety continue to grow, innovations like magnetic biochar gel may offer a practical and sustainable path forward for cleaner agriculture.
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Journal Reference: Gao, Y., Chen, H., Wang, F. et al. Magnetic silicon-enriched biochar for effectively mitigating As and Sb in soil-rice continuum: from integrated geochemical, microbial, and phytophysiological insights. Biochar 8, 74 (2026).
https://doi.org/10.1007/s42773-026-00579-y
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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
Magnetic silicon-enriched biochar for effectively mitigating As and Sb in soil-rice continuum: from integrated geochemical, microbial, and phytophysiological insights
Coffee waste transformed into high-performance, biodegradable insulation material
Biochar Editorial Office, Shenyang Agricultural University
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Highly porous biochar from spent coffee ground for fully green thermal insulating composites with thermal conductivity of 0.04 W m−1 K−1
view moreCredit: Sung Jin Kim & Seong Yun Kim
A new study has transformed everyday coffee waste into a high-performance, eco-friendly insulation material, offering a promising alternative to petroleum-based products widely used in buildings and packaging.
Researchers have developed a biodegradable composite made from spent coffee grounds, a common global waste product, and a natural polymer. By converting coffee waste into a highly porous biochar and combining it with ethyl cellulose, the team created a material that delivers strong thermal insulation while remaining environmentally sustainable.
“Coffee waste is produced on a massive scale worldwide, yet most of it ends up in landfills or is incinerated,” said the study’s corresponding author. “Our work shows that this abundant waste stream can be upcycled into a high-value material that performs as well as commercial insulation products while being far more sustainable.”
Thermal insulation materials play a key role in reducing energy use in buildings, transportation, and food systems. However, commonly used materials such as expanded polystyrene are derived from fossil fuels and can pose environmental and disposal challenges. The newly developed composite addresses these issues by using renewable, biodegradable components.
The research team focused on overcoming a major limitation of raw coffee waste, which has relatively low porosity and limited insulation performance. Through a controlled carbonization process, they produced a biochar with a highly porous structure. This porous architecture is essential because it traps air, which has very low thermal conductivity and helps reduce heat transfer.
To further enhance performance, the researchers introduced a “pore restoration” strategy. They used environmentally friendly solvents to prevent the polymer matrix from filling the pores of the biochar during fabrication. This step preserved the internal pore structure and maximized insulation efficiency.
The result was a composite with a thermal conductivity of just 0.04 W per meter per Kelvin, a level comparable to commercial expanded polystyrene. Materials with thermal conductivity below 0.07 W per meter per Kelvin are generally considered effective insulators, placing this new material among top-performing options.
Beyond performance, the composite offers important environmental advantages. It is fully derived from renewable resources and does not rely on toxic or hazardous substances. The material also demonstrated biodegradability in laboratory tests, suggesting it could help reduce long-term environmental impacts associated with insulation waste.
The study highlights the importance of balancing material structure. While high porosity improves insulation by trapping air, excessive graphitic carbon structures can increase heat transfer. By optimizing processing conditions, the researchers achieved a balance that maximized insulation performance.
The potential applications of this material are wide-ranging. The team demonstrated its use in a model building-integrated photovoltaic system, where it effectively reduced heat transfer from solar panels. This suggests it could be used in energy-efficient building design, helping regulate indoor temperatures while supporting renewable energy systems.
In addition to construction, the material could be applied in packaging, transportation, and other industries where thermal management is critical. Its sustainable nature makes it especially attractive as industries seek alternatives to fossil-based materials.
“This approach not only improves material performance but also contributes to a circular economy,” the researcher added. “By turning waste into a functional product, we can reduce environmental burdens while creating new opportunities for sustainable materials.”
With millions of tons of coffee waste generated globally each year, this innovation points to a scalable pathway for converting everyday waste into advanced, eco-friendly technologies.
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Journal Reference: Kim, S.J., Kim, S.Y. Highly porous biochar from spent coffee ground for fully green thermal insulating composites with thermal conductivity of 0.04 W m−1 K−1. Biochar 8, 73 (2026).
https://doi.org/10.1007/s42773-026-00584-1
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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
Highly porous biochar from spent coffee ground for fully green thermal insulating composites with thermal conductivity of 0.04 W m−1 K−1
