Underground water source in North China Plain (NCP) is limited and extensively explored for wheat irrigation, which has caused high carbon emission. Reduced irrigation strategies and soil amendments have been advocated for sustainable agricultural production. However, the interactive effects of irrigation schedule and soil amendment on direct and indirect greenhouse gas (GHG) emissions, soil organic carbon (SOC) sequestration and carbon footprint (CF) have rarely been systematically quantified. A two-year field study was conducted in wheat season under three irrigation schedules (W0: pre-sowing irrigation only, W1: pre-sowing + jointing irrigation, and W2: pre-sowing + jointing + anthesis irrigation) and three fertilization types (Fc: chemical fertilizer only, Fm: chemical fertilizer + manure, and Fb: chemical fertilizer + biochar). In the Fc treatments, direct emissions from soil N₂O and CH₄ significantly decreased from W2 or W1 to W0, but SOC also decreased from W2 to W1 or W0. Net GHG emissions (${\mathrm{GHG}}_{\mathrm{net}}$) was 14.6% higher in W1 +Fc but 6.0% lower in W0 +Fc compared with W2 +Fc because of the difference in electricity use for irrigation. Notably, the CF in W1 +Fc and W0 +Fc was 40.9% and 63.8% higher than in W2 +Fc mainly due to yield loss. Compared with Fc, direct emissions averaged 63.1% higher under Fm coupled with increased soil nitrate content, microbial biomass carbon (MBC) and nitrogen (MBN). The SOC significantly decreased from W0, W1 to W2 under Fm. Under the identical irrigation level, SOC stocks were 40.0% and 53.9% higher in Fm than in Fc under W1 and W0, while no significant difference under W2. Relative to Fc treatments, under Fm, CF was 28.5% lower in W0 but 6.2% and 45.7% higher in W1 and W2. Compared with Fc, direct emissions averaged 7.7% lower under Fb due to smaller MBN and higher soil porosity under Fb. The CF was lower in Fb than in Fc resulting from SOC increase. Thus, manure and biochar amendment could decrease CF following reduced irrigation, although manure application increased the risk of C loss.

华北平原（NCP）地下水资源有限，大量开采用于小麦灌溉，导致高碳排放。为可持续农业生产提倡减少灌溉策略和土壤改良剂。然而，很少系统地量化灌溉计划和土壤改良对直接和间接温室气体 (GHG) 排放、土壤有机碳 (SOC) 封存和碳足迹 (CF) 的交互影响。在三种灌溉计划（W0：仅播前灌溉，W1：播前+拔节灌溉，W2：播前+拔节+开花期灌溉）和三种施肥类型（ Fc:仅化肥，Fm：化肥+有机肥，Fb：化肥+生物炭）。在Fc 处理中，土壤N ₂ O 和CH ₄的直接排放从W2 或W1 显着降低到W0，但SOC 也从W2 降低到W1 或W0。净温室气体排放量（${\mathrm{温室气体}}_{\mathrm{网}}$) 与 W2 +Fc 相比，W1 +Fc 高 14.6%，但 W0 +Fc 低 6.0%，这是因为灌溉用电量不同。值得注意的是，W1 +Fc 和 W0 +Fc 中的 CF 分别比 W2 +Fc 高 40.9% 和 63.8%，这主要是由于产量损失。与 Fc 相比，Fm 下的直接排放量平均高出 63.1%，同时土壤硝酸盐含量、微生物生物量碳 (MBC) 和氮 (MBN) 增加。在 Fm 下，SOC 从 W0、W1 到 W2 显着下降。在相同灌溉水平下，W1 和 W0 下 Fm 的 SOC 储量比 Fc 高 40.0% 和 53.9%，而 W2 下无显着差异。相对于 Fc 处理，在 Fm 下，CF 在 W0 中降低 28.5%，但在 W1 和 W2 中分别升高 6.2% 和 45.7%。与 Fc 相比，由于 MBN 较小和较高，Fb 下的直接排放平均降低 7.7%Fb 下的土壤孔隙率。由于 SOC 增加，Fb 中的 CF 低于 Fc。因此，粪肥和生物炭改良剂可以在减少灌溉后降低 CF，尽管施用粪肥会增加 C 损失的风险。