A new perspective published in Biochar warns that biochar's long-term carbon storage potential and its soil improvement benefits should not be treated as the same thing. The authors argue that clearer communication is urgently needed as biochar becomes a major player in voluntary carbon markets and climate mitigation strategies.
Biochar, a carbon-rich material produced by heating organic residues under low-oxygen conditions, is widely promoted for both carbon dioxide removal and agricultural benefits. However, the paper explains that these two goals often require different types of biochar. Highly stable biochar, often produced at higher pyrolysis temperatures, can store carbon for long periods but tends to be more chemically inert. In contrast, lower-temperature biochar may retain more surface functional groups that help support nutrient retention, water retention, microbial activity, and pollutant stabilization, but it may not be as durable for long-term carbon storage.
"Biochar is not a single, uniform product," said lead author Robert W. Brown. "A biochar designed for durable carbon removal may not deliver the same soil benefits as one designed as a soil conditioner. Recognizing this distinction is essential for credible science, policy, and carbon markets."
The authors highlight that feedstock type, pyrolysis temperature, and resulting chemical properties, especially hydrogen to carbon and oxygen to carbon ratios, should be reported more consistently. Without these details, claims about both climate benefits and agricultural co-benefits may become overstated or misleading.
The perspective also notes that soil context matters. Degraded or tropical soils may show stronger responses to biochar application than productive temperate soils, while activation strategies such as composting, fertilizer blending, or microbial inoculation may help enhance the soil benefits of more stable biochars.
The authors call for a "designer biochar" approach, in which products are tailored to specific end uses rather than marketed as universally beneficial. As biochar carbon credits continue to expand, transparent reporting and realistic claims will be vital to maintain trust and avoid misallocation of climate resources.
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Journal Reference: Brown, R.W., Chadwick, D.R. & Jones, D.L. Clarifying the conflation of biochar carbon stability and its soil co-benefits. Biochar 8, 67 (2026).
https://doi.org/10.1007/s42773-026-00581-4
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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.
