Document Type : Original Article
Authors
1
Department of Soil Science and Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Tehran, Iran.
2
Department of Irrigation and Reclamation Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Tehran, Iran.
Abstract
This study aimed to investigate the effect of biochar on greenhouse gas emissions, particularly CO₂ and N₂O. Biochar influences environmental cycles by altering the physical, chemical, and biological properties of soil. The results showed that biochar produced from agricultural residues at 400 °C achieved the highest reduction in CO₂ emissions (240 mg kg⁻¹), while increasing the temperature to 600 °C reduced this effect and raised N₂O emissions to 45 mg kg⁻¹. The C:N ratio and feedstock type were key determinants; plant-derived biochars with higher C:N ratios were more effective in reducing CO₂ emissions, whereas manure-based biochars in moist soils tended to increase N₂O emissions. Biochar derived from peanut shells showed the lowest, and pig manure biochar the highest, levels of CO₂ and N₂O emissions. Particle size was also an important factor; coarser biochars (5–10 mm) reduced N₂O and CO₂ emissions by 41.7% and 39.4%, respectively, compared to finer particles (0.5–2 mm). These effects were attributed to the biochar’s chemical composition, porous structure, influence on soil microbial activity, and environmental factors such as moisture and temperature. Overall, selecting biochar with an optimal production temperature, stable feedstock, and appropriate particle size can effectively mitigate greenhouse gas emissions and improve soil quality.
Keywords
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