Biochar amendments mitigate soil greenhouse gas emissions by shifted soil properties, enzyme activities, and nitrogen cycling processes

作者：Mbezele Junior Yannick Ngaba, Abubakari Said Mgelwa, Muhammed Mustapha Ibrahim, Heinz Rennenberg, Bin Hu · 发表于：Carbon Research · 年份：2026 · DOI：10.1007/s44246-025-00241-5 · 被引用次数：6 · 研究领域：Soil Carbon and Nitrogen Dynamics、Agriculture Sustainability and Environmental Impact、Atmospheric and Environmental Gas Dynamics

Abstract Amending agricultural soils with biochar has emerged as a promising approach to sustainably mitigate soil greenhouse gas (GHG) emissions, but information on mechanisms underlying biochar-induced emission dynamics of GHGs remains limited. Our study aimed to comprehensively explore the significance of biochar mediated changes of soil properties, enzyme activities, and nitrogen cycling processes, for mitigating GHG emissions and lowering the concomitant global warming potential (GWP). For this purpose, we conducted a meta-analysis of 78 published studies investigating the effects of biochar amendments on soil properties in agricultural systems worldwide. Biochar amendment significantly increased soil porosity, moisture and total carbon (+ 57% to + 62%), but also soil organic carbon (+ 24%) and total nitrogen (+ 26%). Additionally, salinity, cation exchange capacity, base saturation, and C:N ratio increased (+ 20% to + 29%), while bulk density, labile organic carbon, ammonium- and ammonia–nitrogen, nitrate- and nitrite-nitrogen decreased (− 8% to –38%). Biochar negatively affected the activities of key soil enzymes, such as β-glucosidase, N-acetyl glucose-aminidase, and acid phosphatase (− 14% to − 34%), enhanced ammonification and biological nitrogen fixation (+ 11% to + 13%), while suppressing denitrification and nitrification (− 6% to − 12%). These shifts contributed to significant reductions in GHG emissions: carbon dioxide (− 24% on average), methane (− 36% to − 22%...