This study investigated the effects of cow manure (NF), sheep manure (YF), and biochar (BC) applications on soil organic carbon (SOC) accumulation and silage corn yield enhancement in saline-alkali farmland in Ningxia. The research aimed to elucidate the impacts of these three organic amendments on soil organic carbon fractions and water-stable aggregate stability, providing theoretical support for carbon sequestration and yield improvement in Ningxia’s saline-alkali fields.[Methods] Seven treatments were established at Baofeng Village, Pingluo County, Ningxia:NF1: 250 kg/mu cow manure application,NF2: 500 kg/mu cow manure application,YF1: 250 kg/mu sheep manure application,YF2: 500 kg/mu sheep manure application,BC1: 250 kg/mu biochar application, BC2: 500kg/mu biochar application, CK: No additional organic fertilizer. Key indicators, including dissolved organic carbon (DOC), microbial biomass carbon (MBC), easily oxidizable organic carbon (ROC), water-stable aggregate particle size distribution, and silage corn yield, were measured.[Results]①Organic amendments significantly increased silage corn yield, with NF2 achieving the highest enhancement (24.99% higher than CK).②Organic amendments markedly elevated soil SOC content. BC2 exhibited the highest SOC after a full growth cycle (27.15% increase compared to pre-application). Except for BC1 and BC2, cow and sheep manure applications significantly increased ROC, DOC, and MBC, with soil carbon pool management indices significantly higher than CK (NF2 being the highest among all treatments).③Organic amendments significantly increased the proportion of >0.25 mm water-stable aggregates and improved mean weight diameter (MWD) compared to CK.④Principal component analysis (PCA) revealed that cow manure application contributed most to silage corn yield, plant height, stem thickness, and increases in active organic carbon fractions (ROC, DOC). Biochar treatments primarily enhanced SOC content and MWD.[Conclusion]500 kg/mu cow manure (NF2) significantly boosted silage corn yield and enriched soil active organic carbon fractions.500 kg/mu biochar (BC2) substantially increased SOC content and demonstrated optimal aggregate-promoting effects. Comprehensive evaluation identified NF2 as the optimal treatment for synergizing carbon sequestration and fertilization efficiency.