A recent study conducted by researchers at the Institute of Applied Ecology and Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, has made significant advancements in understanding the temperature sensitivity of soil gaseous nitrogen (N₂O and N₂) loss in forest ecosystems. The study addresses the crucial role of gaseous nitrogen loss in nitrogen limitation and its implications for carbon sink function in terrestrial ecosystems, particularly in the context of climate warming.

The research team developed a novel technique using ¹⁵N tracer to quantify the production rates of N₂O and N₂ derived from denitrification in forest soils across 18 sites in China, covering a wide range of climatic gradients. The results revealed an exponential increase in denitrification N₂O and N₂ production rates with rising temperature, exhibiting a geographical pattern. Importantly, the study found consistent temperature sensitivity for N₂O and N₂ release across different climatic zones, with Q₁₀ values of 2.1 ± 0.5 and 2.6 ± 0.6, respectively.

The temperature sensitivity obtained in this study were comparable to those reported for denitrification in aquatic ecosystems, suggesting a consistent response across soil and marine sediment environments. This consistency facilitates future model simulations and predictions of denitrification response under global warming. Notably, the study highlighted that N₂O, a potent greenhouse gas, would be further exacerbated by warming, creating a positive feedback loop on climate change. Additionally, a warmer climate was found to promote more complete denitrification, leading to increased soil gaseous nitrogen loss as N₂.

The study emphasized that the loss of gaseous nitrogen and resulting nitrogen limitation due to climate warming would likely further restrict the primary productivity and carbon sink function of terrestrial ecosystems, as most forests currently remain nitrogen-limited. To assess the impact of global warming on forest soil gaseous nitrogen losses, the researchers applied the ecosystem process model DyN-LPJ to simulate future global forest soil denitrification gaseous nitrogen release under different warming scenarios (SSP2-4.5 and SSP5-8.5). The model projected an increase in N₂O and N₂ release rates by 2100 under these scenarios.

In conclusion, this study provides important insights into the temperature sensitivities of N₂O and N₂ release from denitrification in forest soils, contributing valuable data for model simulations. The findings enhance our understanding of the intricate carbon and nitrogen coupling processes in forest ecosystems and their feedback mechanisms in the face of future warming.