Combined Effects of Tillage, Crop Rotation, and Biochar on Estimated Net Global Warming Potential in a Rainfed Wheat Agroecosystem

Document Type : Original Article

Authors
1 Department of Plant Production and Genetics, Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Islamic Republic of Iran.
2 Agricultural Research, Education and Extension Organization AREEO, Tabriz, Islamic Republic of Iran.
Abstract
Conservation-oriented management practices, such as reduced soil disturbance, diversified crop rotations, and biochar application, have been increasingly considered as potential approaches to reduce the environmental impact of cereal production systems. This study evaluated the effects of tillage system, crop rotation, and biochar application on soil carbon and estimated greenhouse gas balance in a rainfed wheat agroecosystem in Khosroshahr, northwestern Iran. A split–split plot experiment was conducted during 2020–2023 using three tillage systems (conventional tillage (CT), reduced tillage (RT), and no-tillage (NT)), three crop rotations (continuous wheat, wheat–fallow–wheat, and wheat–grass pea–wheat), and three biochar rates (0, 5, and 10 t ha⁻¹). Climate impacts were quantified using IPCC Tier 1 emission factors with management-specific adjustments. Management practices significantly affected soil carbon, grain yield, and estimated greenhouse gas balance. Soil organic carbon was 19.5 to 28.7 t C ha⁻¹, while estimated GWPnet varied from −11053 to +466 kg CO₂-eq ha⁻¹ across treatments. Conservation-oriented systems, particularly NT and RT combined with biochar application, generally produced more negative estimated GWPnet values than CT systems.
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Articles in Press, Accepted Manuscript
Available Online from 22 September 2026