Biochar shows promise for healthier soils and stronger forests, but careful use is key
image: Biochar impact on soil health and tree-based crops: a review
Credit: Joao A. Antonangelo, Xiao Sun & Humberto de Jesus Eufrade-Junior
A growing body of research suggests that biochar, a charcoal-like material made from plant and agricultural waste, could play a major role in improving soil health and supporting more resilient forests. A new review study brings together over two decades of research to evaluate how biochar affects soil quality and tree-based crops, while also highlighting important risks and knowledge gaps.
“Biochar has enormous potential as a sustainable tool for improving soil and supporting tree growth, but its success depends on how and where it is used,” said the study’s lead author. “Our goal was to provide a balanced understanding of both its benefits and its limitations.”
Biochar is produced through a process called pyrolysis, which heats organic materials such as wood, crop residues, or manure in a low-oxygen environment. This process creates a stable carbon-rich material with a highly porous structure. These properties allow biochar to retain water and nutrients in soil, making them more available to plants over time.
The review finds that biochar can significantly improve soil structure by increasing porosity and aggregation. This helps roots grow more easily, enhances water infiltration, and reduces erosion. In many cases, soils treated with biochar also show higher water retention, which is particularly valuable in drought-prone regions.
In forestry systems, these improvements translate into measurable benefits for trees. Studies analyzed in the review report increases in tree biomass, improved drought tolerance, and enhanced resistance to pests and diseases. In some cases, tree growth increased by more than 20 percent, while overall biomass gains reached over 40 percent in certain species and environments.
Another major advantage is carbon sequestration. Because biochar is highly stable, it can store carbon in soils for decades or even centuries. This makes it a promising strategy for mitigating climate change while simultaneously improving land productivity.
However, the study emphasizes that biochar is not a one-size-fits-all solution. Its effectiveness depends on factors such as the type of feedstock used to produce it, the temperature of production, soil conditions, and the species of trees involved.
Potential risks also need to be carefully managed. For example, biochar can increase soil pH, which may benefit acidic soils but harm plants in already alkaline conditions. It can also temporarily immobilize nutrients, making them less available to plants if applied incorrectly or in excessive amounts. In some cases, the benefits of biochar were minimal or inconsistent, especially in fertile soils where improvements are less needed.
The authors stress that more long-term and site-specific studies are required to better understand how biochar behaves in different environments. Economic considerations and practical implementation strategies also remain key challenges for large-scale adoption.
Despite these uncertainties, the overall conclusion is optimistic. Biochar offers a powerful opportunity to enhance soil health, support sustainable forestry, and contribute to climate solutions.
“This research highlights that biochar can be a valuable tool for the future of sustainable land management,” the author added. “But to unlock its full potential, we need tailored approaches that consider local soil, climate, and crop conditions.”
As global demand grows for sustainable agricultural and forestry practices, biochar may become an increasingly important part of the solution.
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Journal Reference: Antonangelo, J.A., Sun, X. & Eufrade-Junior, H.J. Biochar impact on soil health and tree-based crops: a review. Biochar 7, 51 (2025).
https://doi.org/10.1007/s42773-025-00450-6
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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.