Continuous biochar amendment to achieve long-term CH4 mitigation in paddy fields under water-saving irrigation: a 5-year experiment

作者：Yu Jin Han, Peng Chen, Zhongxue Zhang, Zhongxue Zhang, Xiaoyuan Yan, Zuohe Zhang, Zuohe Zhang, Zuohe Zhang, Tiecheng Li, Tangzhe Nie, Sicheng Du · 发表于：Biochar · 年份：2026 · DOI：10.1007/s42773-026-00578-z · 被引用次数：9 · 研究领域：Soil Carbon and Nitrogen Dynamics、Atmospheric and Environmental Gas Dynamics、Landfill Environmental Impact Studies

Abstract Biochar amendment is an effective strategy for mitigating methane (CH 4 ) emissions in paddy fields. However, the long-term efficacy of different biochar amendment strategies for mitigating CH 4 emissions remains unclear, particularly under different water management regimes. To address this knowledge gap, a 5-year (2018–2022) field experiment was conducted to determine CH 4 production potential, CH 4 oxidation potential, and CH 4 emissions in paddy fields under six treatments: flooded irrigation (F) without biochar amendment (FB0), F with once biochar amendment (12.5 t ha −1 , FB1), F with continuous biochar amendment (2.5 t ha −1 year −1 , FB5), controlled irrigation (C) without biochar amendment (CB0), C with once biochar amendment (12.5 t ha −1 , CB1), and C with continuous biochar amendment (2.5 t ha −1 year −1 , CB5). Additionally, random forest analysis and structural equation modeling (SEM) were used to elucidate interaction pathways among biochar amendment, water management, CH 4 production and oxidation potentials, and key soil properties affecting CH 4 emissions. In the first year, once biochar amendment demonstrated optimal CH 4 mitigation efficacy under different water management regimes, reducing cumulative CH 4 emissions by 18.87–36.32% compared to other treatments. However, this mitigation effect diminished progressively over 5 years under different water management regimes, with the most rapid decline occurring under C. Consequently, there was no sig...