Abstract Given the high nitrogen (N) fertilizer input in crop production systems, the residual effects of the N fertilizer have been increasing continuously. However, its influence on methane (CH4) emissions remains unknown. A field experiment was carried out to investigate the response of CH4 emissions from rice cultivation to the preceding rapeseed N fertilization in a rapeseed-rice rotation system. The N fertilizer was applied during the rapeseed season at N loading rates of 0 and 150 kg N ha−1. During the rice season, the original treatment during the rapeseed season was split into with and without N application subtreatments, totaling in four treatments (N0–0, N0–150, N150–150, and N150–0). Results showed that CH4 emissions were not influenced by N fertilization during the rapeseed season. However, that N fertilization remarkably enhanced CH4 emissions at the seedling stage of the rice-growing season in the fertilized or nonfertilized treatments. This result was caused by the increased soil carbon budget and soil ammonium (NH4+-N) content. The residual effects of N fertilizer contributed 20.3% (N150–0) and 17.5% (N150–150) to the cumulative CH4 emissions of the whole rice-growing season. CH4 emissions at the tillering stage were significantly (p

中文翻译：

---

先前施氮肥通过增加油菜-水稻轮作中的土壤碳储量来调节水稻种植中的 CH4 排放

摘要 鉴于作物生产系统中氮肥的高投入，氮肥的残留效应不断增加。然而，它对甲烷 (CH4) 排放的影响仍然未知。通过田间试验研究了油菜-水稻轮作系统中水稻种植 CH4 排放对油菜前施氮肥的响应。氮肥在油菜籽季节以 0 和 150 kg N ha-1 的氮负载率施用。在稻季，油菜季的原始处理分为施肥和不施氮亚处理，共四个处理（N0-0、N0-150、N150-150和N150-0）。结果表明，CH4 排放不受油菜季节施氮的影响。然而，施氮和未施氮处理显着增加水稻生长期苗期 CH4 排放。这一结果是由增加的土壤碳收支和土壤铵 (NH4+-N) 含量引起的。氮肥的残留效应对整个水稻生长季的 CH4 累积排放贡献了 20.3%（N150-0）和 17.5%（N150-150）。分蘖期 CH4 排放显着（p