Universal temperature sensitivity of denitrification nitrogen losses in forest soils

Soil nitrous oxide (N2O) and dinitrogen (N2) emissions from
denitrification are crucial to the global nitrogen (N)
cycle. However, the temperature sensitivities of gaseous N losses
in forest soils are poorly understood, limiting our ability to predict N
cycling responses to global warming. We quantified temperature
sensitivities (Q10) of denitrification-derived potential N2O and
N2 production ex-situ for 18 forest soils across China.
N2O and N2 production rates increased exponentially with
temperature, showing large variation among soils. By contrast, the
Q10 values for N2O (2.1±0.5) and N2 (2.6±0.6) were
surprisingly similar across soils. N2 was more sensitive to temperature
than N2O, suggesting warming could promote complete denitrification. The
Q10 values for denitrification (2.3±0.5) were similar to
those reported for aquatic sediments. Collectively, our results indicate a
universal temperature sensitivity of gaseous N losses from
denitrification, which will facilitate modelling N losses in response to
warming on the global scale.