【目的】研究炭基肥及增施生物炭对覆膜水稻产量、氮素利用的影响，以期为水稻覆膜技术可持续发展应用提供理论依据。【方法】以优质粳型常规水稻品种浙禾香2号和籼粳杂交稻甬优538为材料，2021年覆膜机插种植设置CK(不施氮)、T1(施用缓释肥)和T2(施用炭基肥)处理。2022年覆膜机插种植设置CK(不施氮)、T2(施用炭基肥)、T3(炭基肥增施 6 t/hm²生物炭)和T4(炭基肥增施 12 t/hm² 生物炭)处理，研究覆膜稻田施用炭基肥对水稻干物质积累、产量及产量构成和氮素吸收利用的影响。【结果】炭基肥促进了覆膜水稻的生长，提高了覆膜水稻产量。炭基肥显著增加水稻干物质积累量，与T1相比干物质积累显著增加5.40%~29.69%，增施生物炭与T2相比增加了覆膜水稻干物质积累量9.28%~46.91%。浙禾香2号整个生长期效果明显，甬优538在后期作用更显著。与T1相比，炭基肥能显著提高水稻产量3.84%~4.65%。增施生物炭较T2进一步提高了覆膜水稻产量7.97%~15.06%；炭基肥促进了覆膜水稻对氮素的吸收利用，提高水稻氮素利用效率。施用炭基肥显著增加覆膜水稻各生长关键时期的氮素积累量4.87%~31.68%，且氮素积累量随炭基肥增施生物炭量的增加而提高，炭基肥增施12 t/hm² 生物炭(T4)氮素积累最高，较施炭基肥(T2)增加11.87%~40.59%。炭基肥降低了覆膜水稻氮素干物质生产率和氮素稻谷生产率，提高了氮肥偏生产力、氮肥农学效率和氮肥吸收利用效率。增施生物炭处理进一步提高氮素利用，减少氮素损失。【结论】覆膜稻田施用炭基肥有利于水稻干物质量和氮素积累量增加，增施生物炭能够进一步提高其效果，从而增加产量，提高氮素利用效率。浙禾香2号增产主要通过增加穗数和每穗粒数，甬优538则通过增加穗数增产，炭基肥增施12 t/hm² 生物炭增产效果最好。

【Objective】To investigate the impact of biochar-based fertilizers and increased biochar application on grain yield and nitrogen utilization of film-mulched rice, aiming to provide a theoretical foundation for sustainable rice mulching technology.【Methods】Utilizing the high-quality conventional japonica rice variety Zhehexiang 2(ZHX2) and the indica-japonica hybrid rice Yongyou 538(YY538), film-mulched mechanical transplanting experiments were conducted in 2021 with CK (no nitrogen application), T1 (slow-release fertilizers), and T2 (biochar-based fertilizers) treatments. In 2022, similar experiments were conducted with CK, T2, T3 (biochar-based fertilizers with an additional 6 t/hm² biochar), and T4 (biochar-based fertilizers with an additional 12 t/hm² biochar) treatments. The study assessed the effects of biochar-based fertilizer application on dry matter accumulation, yield, yield components, and nitrogen uptake and utilization in mulched rice fields. 【Result】 Biochar-based fertilizers enhanced the growth and yield of mulched rice. They significantly increased dry matter accumulation by 5.40% to 29.69% compared to T1, and additional biochar application further increased dry matter accumulation by 9.28% to 46.91% compared to T2. The impact was consistent throughout ZHX2's growth duration, with YY538 showing more significant effects in the later stages. Biochar-based fertilizers significantly boosted rice yield by 3.84% to 4.65% compared to T1. Increased biochar application led to a 7.97% to 15.06% yield increase compared to T2. Biochar-based fertilizers enhanced nitrogen uptake and utilization, improving nitrogen utilization efficiency. They increased nitrogen accumulation in critical growth periods by 4.87% to 31.68%, with higher accumulation observed with additional biochar application. The highest nitrogen accumulation was achieved in T4, showing an 11.87% to 40.59% increase compared to T2. Biochar-based fertilizers reduced nitrogen dry matter productivity and nitrogen grain production efficiency but enhanced nitrogen partial factor productivity, nitrogen agronomic efficiency, and nitrogen recovery efficiency. Increased biochar application further improved nitrogen utilization and reduced losses.【Conclusion】 Applying biochar-based fertilizers in mulched rice fields enhances dry matter mass and nitrogen accumulation, with additional biochar application further improving these effects, leading to increased yield and nitrogen utilization efficiency. The yield increase in ZHX2 was primarily due to panicle number and grain number per panicle, while in YY538, it was due to panicle number, with the best effect observed in T4.