Global warming may exacerbate drought, decrease crop yield and affect greenhouse gas (GHG) emissions in semi-arid regions. However, the interactive effects of increases in temperature and water availability on winter wheat yield and GHG emissions in semi-arid climates are not well-understood. Here, we report on a two-year field experiment that examined the effects of a mean soil temperature increase of ~2 °C (at 5 cm depth) with and without additional irrigation on wheat yield and GHG emissions. Infrared heaters were placed above the crop canopy at a height of 1.8 m to simulate warming. Fluxes of CH₄, CO₂ and N₂O were measured using closed static chamber technique once per week during the wheat growing seasons. Warming decreased wheat yield by 28% in the relatively dry year of 2015, while supplemental irrigation nullified the warming effect completely. Warming did not alter the wheat yield significantly in the relatively wet year of 2016, but supplemental irrigation with no warming decreased the wheat yield by 25%. Warming increased CO₂ emissions by 28% and CH₄ uptake by 24% and tended to decrease N₂O emissions. Supplemental irrigation increased N₂O emissions but had little effect on CO₂ emissions and CH₄ uptake. Evidently, warming and supplemental irrigation had interactive effects on wheat yield, GHG emissions and GHG emissions intensity. Precision irrigation appears to be a means of simultaneously increasing wheat yield and reducing GHG emissions under warming conditions in semi-arid areas.

全球变暖可能加剧干旱，降低作物产量并影响半干旱地区的温室气体排放。但是，在半干旱气候下，温度和水供应量增加对冬小麦单产和温室气体排放的互动影响尚未得到很好的理解。在这里，我们报告了一项为期两年的田间试验，该试验研究了在不增加灌溉和不增加灌溉的情况下，平均土壤温度升高〜2°C（在5 cm深度）对小麦产量和温室气体排放的影响。将红外加热器放置在作物冠层上方，高度为1.8 m，以模拟变暖。CH ₄，CO ₂和N _2的通量在小麦生长季节，每周使用密闭静态室技术测量一次O。在2015年相对干燥的一年里，变暖使小麦单产降低了28％，而补充灌溉完全消除了变暖效应。在2016年相对潮湿的一年里，变暖并没有显着改变小麦的产量，但是没有变暖的补充灌溉使小麦的产量降低了25％。气候变暖使CO ₂排放增加了28％，CH ₄吸收增加了24％，并倾向于减少N ₂ O排放。补充灌溉增加了N ₂ O排放，但对CO ₂排放和CH _4的影响很小摄取。显然，增温和补充灌溉对小麦产量，温室气体排放和温室气体排放强度具有交互作用。在半干旱地区，在温暖的条件下，精确灌溉似乎是同时增加小麦单产和减少温室气体排放的一种手段。