本研究旨在揭示利用有机肥部分替代氮肥实现作物增产和土壤改良的可能性及其机理。以南粳9108为供试水稻品种，设置4个处理：常规施肥（T1），低量自配有机肥部分替代氮肥（T2），高量自配有机肥部分替代氮肥（T3），不施肥（CK），T1、T2和T3采用等氮量设计（315 kg/hm²），开展田间试验。研究结果表明：较常规施肥，有机肥部分替代氮肥能够显著降低土壤pH、提升土壤有效磷和速效钾、增强脲酶和碱性磷酸酶活性、增加土壤有机质和碱解氮；能够显著增加收获时的水稻干物质积累量，一定程度地提升水稻株高，促进水稻分蘖并且增加穗粒数、结实率和千粒重。有机肥部分替代氮肥能够实现土壤改良和水稻增产。

A field experiment was carried out to reveal the possibility and mechanism of partially replacing nitrogen fertilizer with organic fertilizer to increase crop yield and improve soil quality, in which, Nanneng 9108 of the rice variety was selected for test, and four treatments were set up (T1, conventional fertilization; T2 and T3, low and high amount of self-prepared organic fertilizer replacing part of conventional nitrogen fertilization; and CK, no fertilization). The results showed that compared with T1, T2 and T3 significantly reduced soil pH, increased the contents of soil organic matter, alkali-hydrolyzed nitrogen, available phosphorus and available potassium, enhanced the activities of urease and alkaline phosphatase, significantly increased rice dry matter accumulation, and increased grain number per spike, seed setting rate, 1000-grain weight and yield during harvest to some extent. In conclusion, organic fertilizer can partially replace conventional nitrogen fertilizer to improve soil quality and increase rice production.

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国家重点研发计划项目（2022YFD1900104）和江苏省沿海开发集团有限公司青年创新项目（2021110101）资助。