Crop straw application in combination with fertilizer nitrogen (N) dose reduction is recommended to improve crop yields and carbon sequestration in soil. This practice may also promote soil nitrous oxide (N₂O) emission, thus partially counterbalancing the expected benefits. However, the full straw return effect on the reduction of soil N₂O to dinitrogen (N₂) is not yet well known, owing to the methodological difficulties in quantifying soil N₂ fluxes against the high atmospheric N₂ concentration. This study was carried out in a long-term experimental field of a calcareous soil cultivated with summer maize and winter wheat in rotation. For the three field treatments since 2006, i.e., optimal fertilizer N with and without full straw return, and the control (without N and straw application), we conducted in- or ex-situ observations on field N₂O fluxes, soil N₂ emissions, crop yields, soil organic carbon (SOC) contents and soil/environmental factors. During a rotation cycle, we found that soil ammonium and nitrite concentrations, moisture and temperature jointly determined the N₂O emissions, while nitrate concentration, dissolvable organic carbon to nitrate-N ratio and moisture jointly dominated the N₂ emissions. Compared to straw removal, the straw return promoted reduction of more soil N₂O to N₂ in the wheat season than in the maize season, showing increases in the N₂ emissions by 57% versus − 10% (P = 0.06). Nevertheless, it significantly enhanced the N₂O emissions measured in situ by approximately 137% and 21% in the wheat and maize seasons, respectively (P < 0.05). It also significantly increased the annual crop yields by 20% on average (P < 0.05). Meanwhile it tended to enhance the SOC stock (0−20 cm) by 15‰ yr⁻¹ (P = 0.14), showing a trend of more intensive carbon sequestration than the direct soil N₂O emission (−948 versus 378 kg CO₂e ha⁻¹ yr⁻¹ on average). We conclude that the long-term full straw return helps to sequester more carbon that offsetting the enhanced N₂O emissions from the calcareous soil in the rotation system as it promotes reduction of more N₂O to N₂ in the wheat season.

建议将作物秸秆施用与肥料氮 (N) 剂量减少相结合，以提高作物产量和土壤中的碳固存。这种做法还可能促进土壤一氧化二氮 (N ₂ O) 的排放，从而部分抵消预期的收益。_{然而，由于在量化土壤 N 2}通量对抗高大气 N ₂浓度的方法学上存在困难，秸秆还田对土壤 N ₂ O还原为二氮 (N ₂ ) 的影响尚不为人所知。这项研究是在一个长期的试验田中进行的，该土壤采用夏玉米和冬小麦轮作种植的钙质土壤。对于 2006 年以来的三个田间处理，即.，最佳施肥 N 有和没有完全秸秆还田，以及控制（没有施氮和施肥），我们对田间 N ₂ O 通量、土壤 N ₂排放、作物产量、土壤有机碳进行了原位或异地观察(SOC) 含量和土壤/环境因素。在一个轮作周期中，我们发现土壤铵和亚硝酸盐浓度、水分和温度共同决定了 N ₂ O 排放，而硝酸盐浓度、可溶性有机碳与硝酸盐-N 比和水分共同主导 N ₂排放。与除草相比，秸秆还田促进了更多土壤 N ₂ O 向 N _2的减少与玉米季节相比，小麦季节的 N ₂排放量增加了 57% ，而− 10% ( P  = 0.06)。然而，它显着提高了小麦和玉米季节原位测量的 N ₂ O 排放量，分别约为 137% 和 21% ( P  < 0.05)。它还显着增加了年平均作物产量20％（P  <0.05）。同时它倾向于将 SOC 储量（0-20 cm）增加 15‰ yr ^-1（P = 0.14），显示出比直接土壤 N ₂ O 排放 更密集的碳固存趋势（-948对378 kg CO₂ e ha ^-1 yr ^-1平均）。我们得出的结论是，长期的全秸秆还田有助于封存更多的碳，从而抵消轮作系统中钙质土壤增加的 N ₂ O 排放，因为它促进了小麦季节更多的 N ₂ O 向 N _{2的减少。}