This study aims at estimating the wheat yield response to future challenges (land degradation and climate change) through a statistical emulator. Data from Global Agro‐ecological Zones on the overall wheat yields of 254 provinces for nine main wheat‐producing countries and corresponding climate and land suitability information were collected to estimate the statistical relationship between regressors and wheat yields. Once the statistical emulator was calibrated, three scenarios were developed to predict, separately and jointly, the impact of climate change and land degradation on wheat yields and productions in 2050 using the global climate model ECHAM4 information under the B2 scenario with the CO₂ fertilization effect. Results showed that under temperature and precipitation projections wheat yield would increase on average by 8% (first scenario); however, the impact of future land suitability (second scenario) on wheat yields would be negative, lowering the average yield (−5%), and overall wheat production (−14%). Combining both effects in the third scenario, future wheat yields would increase by 4.6%, while overall production will decrease by 5.5% since the harvest area will be reduced by 9.7%. Thus, land degradation more than climate change is likely to pose significant challenges for overall wheat production in the future.

中文翻译：

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土地退化和气候变化：对小麦单产的全球影响

这项研究旨在通过统计仿真器估算小麦产量对未来挑战（土地退化和气候变化）的反应。来自全球农业生态区的数据收集了9个主要小麦生产国254个省的小麦总产量，并收集了相应的气候和土地适宜性信息，以估算回归因子与小麦产量之间的统计关系。一旦对统计仿真器进行了校准，便会使用B2情景和CO ₂情景下的全球气候模型ECHAM4信息，开发出三种情景来分别和共同预测2050年气候变化和土地退化对小麦产量和产量的影响。施肥效果。结果表明，在温度和降水预测下，小麦单产将平均提高8％（第一种情况）。但是，未来土地适宜性（第二种情况）对小麦单产的影响为负，降低了平均单产（−5％）和小麦总产量（−14％）。结合第三种情况下的两种影响，未来小麦单产将增加4.6％，而总产将减少5.5％，因为收割面积将减少9.7％。因此，土地退化比气候变化更可能对未来的小麦总产构成重大挑战。