Universal temperature sensitivity of denitrification nitrogen losses in forest soils

Soil nitrous oxide (N2O) and dinitrogen (N2) emissions from denitrification are crucial to the nitrogen (N) cycle. However, the temperature sensitivities (Q10) of gaseous N losses in forest soils are poorly understood, with implications for prediction of N cycle responses to warming. Here, we quantify temperature sensitivities of denitrification-derived potential N2O and N2production. Using soils from 18 forest sites in China along a 4,000 km north–south transect we find that N2O and N2production rates increased with temperature, with large variations across soils. In contrast, the Q10values for N2O (2.1 ± 0.5) and N2(2.6 ± 0.6) were similar across soils. N2was more sensitive to temperature than N2O, suggesting that warming could promote complete denitrification. Moreover, the Q10for denitrification (2.3 ± 0.5) was comparable to Q10for aquatic sediments. This finding of universal temperature sensitivity of gaseous N losses from denitrification will facilitate modelling N losses in response to warming globally.