Excessive fertilization, poor management, low nitrogen (N) use efficiency and heavy pollution are the current issues that exist in intensively cultivated summer maize-winter wheat rotation system in China. To address these problems, we adopted the Nutrient Expert (NE) decision support system and compared it with the Farmer's Practice (FP). We explored the effects of NE and FP on grain yield, N use efficiency, soil N accumulation, environmental cost, and profitability in the rotation system from 2009 to 2018. The results showed that there was no significant yield difference between the NE (14.4 Mg ha⁻¹) and FP (14.3 Mg ha⁻¹), while reducing N application by 23.1 % in NE. Compared with the FP treatment, the NE increased the apparent recovery efficiency of N (apparent RE_N), accumulated recovery efficiency of N (accumulated RE_N), agronomic efficiency of N (AE_N) and partial factor productivity of N (PFP_N) by 25.0 %, 26.8 %, 31.1 % and 32.1 %, respectively, which also indicated a less N loss achieved by NE. The NE resulted in less N accumulation in the soil profile than FP, with reductions of 32.1 % and 44.2 % in the 0−100 cm and 60−100 cm soil layers, respectively. Moreover, calculations of economic benefit that considered the environmental cost showed that NE had an economic advantage (13.8 % of increase in net income; and 27.2 % of decrease in environmental cost) over FP. This study proved that long-term NE management is a sustainable management approach with advantages in maintaining grain yield, improving N use efficiency and profitability, and reducing environmental cost for the summer maize-winter wheat rotation system.

施肥过多、管理不善、氮（N）利用效率低、污染严重是目前我国夏玉米-冬小麦集约化轮作制度存在的问题。为了解决这些问题，我们采用了营养专家（NE）决策支持系统，并将其与农民实践（FP）进行了比较。我们探讨了 2009 年至 2018 年轮作系统中 NE 和 FP 对粮食产量、氮利用效率、土壤氮积累、环境成本和盈利能力的影响。结果表明，NE (14.4 Mg ha ^-1 ) 和 FP (14.3 Mg ha ^-1 )，同时将 NE 中的施氮量减少 23.1 %。与FP处理相比，NE提高了N的表观回收效率（表观RE _N)、N 的累积回收效率（accumulated RE _N）、_{N 的}农艺效率（AE _N）和_{N 的}部分要素生产力（PFP _N) 分别减少了 25.0 %、26.8 %、31.1 % 和 32.1 %，这也表明 NE 实现的 N 损失较少。NE 导致土壤剖面中的 N 积累少于 FP，在 0-100 cm 和 60-100 cm 土层中分别减少了 32.1% 和 44.2%。此外，考虑环境成本的经济效益计算表明，NE 比 FP 具有经济优势（净收入增加 13.8%；环境成本减少 27.2%）。本研究证明，长期氮肥管理是一种可持续的管理方法，对于夏玉米-冬小麦轮作制度，在保持粮食产量、提高氮肥利用效率和盈利能力、降低环境成本等方面具有优势。