Climatic change effects on crop yields are expected to be crop‐ and site specific. Here, Decision Support System for Agrotechnology Transfer models were used to evaluate climatic change effects and mitigation strategies on maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] yields in soils of the subtropical and semi‐arid region of Chaco. Simulations were performed for the DK747 and A8000 genotypes, calibrated for the CERES‐Maize model in a previous report and for the CROPGRO‐Soybean model in the present study, respectively. Both crops markedly differ in their response to climatic change and putative levels of atmospheric CO₂ concentration. The observed significant reductions in maize yields in future climate scenarios (5–42% compared with the baseline, 1986–2010) were more associated with increased temperatures that shortened the crop cycle than with water stress. Delaying the sowing date is a feasible strategy to mitigate this effect. Projected temperature increases are expected to play a secondary role in determining soybean yields. Instead, water stress will continue to be an important constraint to soybean yield in the context of global warming, but this effect is strongly affected by rainfall regimes. Responses to raising CO₂ levels were more pronounced in soybean (+10–40%) than in maize (+2–4%). Soil degradation exacerbated the negative effects of global warming on crop yields, especially on maize, which highlights the importance of soil conservation practices. The observed high interannual climatic variability and the different sensitivities of maize and soybean to climatic variables indicate that crop diversification would be the key to improve the resilience of the agrosystems under the future scenarios.

中文翻译：

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模拟南美地区玉米和大豆对气候变化和土壤退化的响应

气候变化对农作物产量的影响预计将因作物和地点而异。在这里，使用了农业技术转移模型的决策支持系统来评估气候变化 对亚热带和半干旱地区土壤中的玉米（Zea mays L.）和大豆[ Glycine max（L.）Merr。]产量的影响和缓解策略。 Chaco。对DK747和A8000基因型进行了仿真，分别针对先前报告中的CERES-玉米模型和本研究中的CROPGRO-大豆模型进行了校准。两种作物对气候变化和大气CO ₂假定水平的反应明显不同专注。在未来气候情景中观察到的玉米单产的大幅下降（与1986-2010年的基准水平相比下降了5–42％）与温度升高，缩短了农作周期的相关性大于与水分胁迫的相关性。推迟播种日期是减轻这种影响的可行策略。预计温度升高将在确定大豆单产中发挥次要作用。取而代之的是，在全球变暖的情况下，水分胁迫将继续成为限制大豆产量的重要因素，但是这种影响受到降雨制度的强烈影响。对提高CO _2的反应大豆（+ 10–40％）比玉米（+ 2-4％）更显着。土壤退化加剧了全球变暖对农作物产量，特别是对玉米产量的负面影响，这突出了土壤保护措施的重要性。观测到的高年际气候变化以及玉米和大豆对气候变量的不同敏感性表明，在未来情况下，作物多样化将是提高农业系统抗逆能力的关键。