A study led by Shaobo Zhang, published in Industrial Crops & Products, investigates how different treatments of tea pruning litter affect soil organic carbon (SOC) mineralization in tea plantations. Researchers compared direct pruning litter addition to soil with its processed forms—biochar and organic fertilizer. The study aimed to determine how these methods influence carbon emissions, microbial activity, and SOC stability.

Results from a 60-day incubation showed that untreated pruning litter caused the highest cumulative CO2 emissions. Emissions decreased by 38% with organic fertilizer use and by 62% with 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 addition, compared to pruning litter. Biochar’s effectiveness is linked to its higher aromatic carbon content, which resists decomposition. Conversely, pruning litter, rich in labile carbon compounds, boosted microbial activity and carbon-degrading enzyme functions, accelerating SOC loss.

The study also explored the role of microbial communities. Biochar and organic fertilizer were associated with reduced populations of carbon-degrading microbes like Acidobacteria and enzyme-related genes (e.g., GH48 and cbhI), contributing to lower carbon loss. These findings suggest that converting pruning litter to biochar is a more sustainable approach, minimizing greenhouse gas emissions while maintaining soil carbon stocks.

This research highlights the potential of biochar to enhance the environmental sustainability of tea plantations, offering a practical solution to mitigate soil carbon loss and contribute to global carbon balance efforts.

SOURCE: Zhang, S., Huang, F., Guo, S., Luo, Y., Zhang, L., Zhang, L., Li, Z., Ge, S., Wang, H., Fu, J., Li, X., & Yan, P. (2025). Mitigation of soil organic carbon mineralization in tea plantations through replacement of pruning litter additions with pruning litter derived biochar and organic fertilizer. Industrial Crops & Products, 225, 120518. https://doi.org/10.1016/j.indcrop.2025.120518