Rice is a staple food for millions, but growing it in calcareous soils presents challenges. These soils tend to fix phosphorus (P), making it unavailable to plants, while also contributing to greenhouse gas emissions, particularly methane (CH₄). A recent study by Keteku et al. in International Journal of Plant Production explores how biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More and silicon, when combined with inorganic fertilizers, can enhance soil fertility, improve rice yields, and reduce CH₄ emissions​.

The researchers conducted a two-year field study, testing different combinations of nitrogen-phosphorus-potassium (NPK) fertilizer, biochar, and silicon (Si). They found that adding biochar significantly improved soil organic carbon content, increasing it by up to 108.5%. The combination of ½NPK + biochar + 100 kg Si per hectare yielded results comparable to full NPK treatments while reducing CH₄ emissions.

Biochar’s ability to retain nutrients and improve soil aeration contributed to higher phosphorus and silicon uptake. Silicon played a key role in strengthening plant structures and enhancing nutrient efficiency. The best results came from treatments combining biochar, Si, and reduced NPK rates, showing that farmers could maintain productivity while cutting fertilizer use and emissions.

The study highlights biochar’s potential as a climate-smart agricultural tool. By integrating it with targeted silicon applications, farmers can boost yields sustainably while mitigating environmental impacts.

Keteku, A. K., Amegbor, I. K., Yeboah, S., Amankwaa-Yeboah, P., Dormatey, R., Agyeman, K., Brempong, M. B., Baafi, E., Asante, M. D., Oppong, A., Poku, S. A., Danquah, E. O., Frimpong, F., Ghanney, P., Addy, S., Obeng, E. A., & Bosompem, F. (2025). Sustaining productivity while reducing methane emission in calcareous soils: Implications of combining inorganic fertilizer and biochar. International Journal of Plant Production. https://doi.org/10.1007/s42106-024-00325-z