Soil emissions of nitrous oxide (N₂O), a potent greenhouse gas associated with agricultural systems, can be reduced by the activity of arbuscular mycorrhizal (AM) fungi. It is unclear, however, whether climate change may impact this ecosystem service provided by AM fungi. To assess the extent that warming may affect AM fungal mediation of N₂O emissions from pastures, we grew lucerne (Medicago sativa, also called alfalfa) and tall fescue (Festuca arundinacea) under ambient (aT) and elevated (eT) temperature (+4 °C) regimes in the presence or absence of the AM fungus Rhizophagus irregularis. N₂O emissions were measured from pots at five timepoints over a four-month period, while total plant biomass, nitrogen, phosphorus and mycorrhizal parameters (root length colonised and extraradical hyphal biomass in soil) were measured following a final destructive harvest. For both species, AM fungi significantly reduced N₂O fluxes to a similar extent under both temperatures. The N₂O reduction due to AM fungal inoculation was not influenced by warming. Overall, AM fungi were shown to reduce N₂O emissions under current and predicted future warming scenarios for these two common pasture species, highlighting the role of microbial symbionts in mediating terrestrial feedbacks to future climate change.

一氧化二氮 (N ₂ O) 是一种与农业系统相关的强效温室气体，可通过丛枝菌根 (AM) 真菌的活动减少土壤排放。然而，尚不清楚气候变化是否会影响 AM 真菌提供的这种生态系统服务。为了评估该升温可影响AM N个真菌调解的程度_2个从牧场O排放，我们长大苜蓿（紫花苜蓿，也称为紫花苜蓿）和高羊茅（高羊茅环境（AT）和升高（ET）温度下）（+ 4 °C) 存在或不存在 AM 真菌Rhizophagus normis 的情况。N ₂在四个月的时间内测量了五个时间点的花盆的 O 排放量，而在最终破坏性收获后测量了植物总生物量、氮、磷和菌根参数（土壤中定植的根长和根外菌丝生物量）。对于这两个物种，AM 真菌在两种温度下都以相似的程度显着降低了 N ₂ O 通量。由于 AM 真菌接种导致的 N ₂ O 减少不受变暖的影响。总体而言，在这两种常见牧场物种的当前和预测的未来变暖情景下，AM 真菌被证明可以减少 N ₂ O 排放，突出了微生物共生体在介导对未来气候变化的陆地反馈中的作用。