Soil clay content determined the temperature response of N2O emissions derived from denitrification

Soil nitrous oxide (N₂O) emissions resulting from denitrification constitute a significant source of greenhouse gas emissions in the agricultural sector. However, how warming affects denitrification-derived N₂O emissions in croplands remains poorly understood, presenting challenges for predicting greenhouse gas feedback loops under climate change. In this study, we evaluated the temperature sensitivity of potential N₂O emissions from denitrification in cropland soils, employing the N₂O site preference approach to differentiate between bacterial and fungal contributions. Our findings reveal that fungal denitrification dominated N₂O emissions; however, warming decreased its contribution from 57.5 % to 51.5 %. Denitrification-derived N₂O emissions displayed significant variability across sites, and a strong positive correlation was observed between soil clay content and the Q₁₀ value of N₂O. This relationship was further supported by the global data provided. Our findings underscore the importance of incorporating both soil properties and fungal processes when projecting future N₂O emissions under global warming scenarios.