Climate change poses a significant threat to agriculture, highlighting the need for adaptation strategies to reduce its impacts. Agronomic adaptation strategies, such as changes in planting dates, fertilization, and irrigation, might sustain crop yield. However, their impact on soil greenhouse gas (GHG) emission is unknown under future climate scenarios. Using the LandscapeDNDC model, we assessed the effect of agronomic adaptation strategies (early sowing, increased fertilization dose, and increased irrigation amount) on soil GHG emission, yield, and yield-scaled GHG emission. A diversified crop rotation (potato – winter wheat – spring barley – faba bean) of a long-term experiment in Denmark was used for model validation. The adaptation practices to climate change were implemented for two representative concentration pathways (RCPs; 4.5 and 8.5) and five coupled global circulation and regional climate models. The adaptation scenarios were contrasted against a baseline scenario under current management practices. Soil-related variables showed better model fit (refined index of agreement ≥ 0.38) and lower errors (mean absolute error ≤ 8.18) than crop-based outputs for model validation. A total yield of ∼29 (± 3) t DW ha, and soil GHG emission of ∼3.02 (± 1.39) t COe ha (RCP8.5) were obtained for the crop rotation system under the baseline for 2071–2100. Early sowing and its combination with increased fertilization decreased the yield compared to the baseline by 6.1 and 4.8 %, respectively (RCP8.5). Conversely, early sowing with increased irrigation, and early sowing with increased fertilization and irrigation, produced higher yields by 2.3 and 4.0 %, respectively (RCP8.5). All the agronomic adaptation strategies increased soil GHG emissions (ranging from 4.1 to 17.8 %) as well as yield-scaled GHG emissions (varying from 3.0 to 12.9 %) (RCP8.5). The highest soil GHG emission was simulated for early sowing in combination with increased fertilization and irrigation. Our study indicates that soil GHG emission will increase in the coming decades and that the agronomic adaptation strategies needed to sustain food production may further exacerbate this emission.

中文翻译：

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气候变化的共同农艺适应策略可能会增加北欧土壤温室气体排放

气候变化对农业构成重大威胁，凸显了采取适应战略以减少其影响的必要性。农业适应策略，例如改变种植日期、施肥和灌溉，可能会维持作物产量。然而，在未来的气候情景下，它们对土壤温室气体（GHG）排放的影响尚不清楚。使用LandscapeDNDC模型，我们评估了农艺适应策略（提前播种、增加施肥剂量和增加灌溉量）对土壤温室气体排放、产量和产量规模温室气体排放的影响。丹麦长期实验的多样化轮作（马铃薯 - 冬小麦 - 春大麦 - 蚕豆）用于模型验证。针对两个代表性浓度路径（RCP；4.5 和 8.5）和五个耦合的全球环流和区域气候模型实施了气候变化适应实践。适应情景与当前管理实践下的基线情景进行了对比。与基于作物的模型验证输出相比，与土壤相关的变量显示出更好的模型拟合（精确一致性指数≥0.38）和更低的误差（平均绝对误差≤8.18）。在 2071-2100 年基线下，轮作系统的总产量为 ∼29 (± 3) t DW ha，土壤温室气体排放量为 ∼3.02 (± 1.39) t COe ha (RCP8.5)。与基线相比，早播及其与增加施肥的结合使产量分别降低了 6.1% 和 4.8% (RCP8.5)。相反，早播并增加灌溉，以及早播并增加施肥和灌溉，产量分别提高了 2.3% 和 4.0% (RCP8.5)。所有农艺适应策略都增加了土壤温室气体排放（从 4.1% 到 17.8%）以及产量规模的温室气体排放（从 3.0% 到 12.9%）（RCP8.5）。模拟了早期播种结合增加施肥和灌溉的最高土壤温室气体排放量。我们的研究表明，未来几十年土壤温室气体排放量将会增加，而维持粮食生产所需的农艺适应策略可能会进一步加剧这种排放。