Cover crops (CC) promote the accumulation of soil organic carbon (SOC), which provides multiple benefits to agro-ecosystems. However, additional nitrogen (N) inputs into the soil could offset the CO2 mitigation potential due to increasing N2 O emissions. Integrated management approaches use organic and synthetic fertilizers to maximize yields while minimizing impacts by crop sequencing adapted to local conditions. The goal of this work was to test whether integrated management, centered on CC adoption, has the potential to maximize SOC stocks without increasing the soil greenhouse gas (GHG) net flux and other agro-environmental impacts such as nitrate leaching. To this purpose, we ran the DayCent bio-geochemistry model on 8,554 soil sampling locations across the European Union. We found that soil N2 O emissions could be limited with simple crop sequencing rules, such as switching from leguminous to grass CC when the GHG flux was positive (source). Additional reductions of synthetic fertilizers applications are possible through better accounting for N available in green manures and from mineralization of soil reservoirs while maintaining cash crop yields. Therefore, our results suggest that a CC integrated management approach can maximize the agro-environmental performance of cropping systems while reducing environmental trade-offs.

中文翻译：

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可持续耕作系统的综合管理：超越田间规模的温室平衡。

覆盖作物（CC）促进土壤有机碳（SOC）的积累，为农业生态系统带来多种好处。然而，由于 N2 O 排放量增加，向土壤中额外输入氮 (N) 可能会抵消 CO2 减排潜力。综合管理方法使用有机和合成肥料来最大限度地提高产量，同时通过适应当地条件的作物排序将影响降至最低。这项工作的目标是测试以 CC 采用为中心的综合管理是否有潜力在不增加土壤温室气体 (GHG) 净通量和其他农业环境影响（如硝酸盐浸出）的情况​​下最大化 SOC 储量。为此，我们对欧盟 8,554 个土壤采样点运行了 DayCent 生物地球化学模型。我们发现，可以通过简单的作物排序规则来限制土壤 N2 O 排放，例如当温室气体通量为正时从豆科作物转向草类 CC（来源）。通过更好地计算绿肥和土壤库矿化中的可用氮，同时保持经济作物产量，可以进一步减少合成肥料的施用。因此，我们的结果表明，CC 综合管理方法可以最大限度地提高种植系统的农业环境绩效，同时减少环境权衡。