| Summary: | The alpine meadow of Zoige Plateau plays a key role in local livestock production of cattle and sheep. However, it remains unclear how animal grazing or its intensity affect nitrous oxide (N<sub>2</sub>O) emissions, and the main driving factors. A grazing experiment including four grazing intensities (G0, G0.7, G1.2, G1.6 yak ha<sup>−1</sup>) was conducted between January 2013 and December 2014 to evaluate the soil nitrous oxide (N<sub>2</sub>O) fluxes under different grazing intensities in an alpine meadow on the eastern Qinghai–Tibet Plateau of China. The N<sub>2</sub>O fluxes were examined with gas collected by the static chamber method and by chromatographic concentration analysis. N<sub>2</sub>O emissions in the growing seasons (from May to September) were lower than that in non-growing seasons (from October to April) in 2013, 1.94 ± 0.30 to 3.37 ± 0.56 kg N<sub>2</sub>O ha<sup>−1</sup> yr<sup>−1</sup>. Annual mean N<sub>2</sub>O emission rates were calculated as 1.17 ± 0.50 kg N<sub>2</sub>O ha<sup>−1</sup> yr<sup>−1</sup> in non-grazing land (G0) and 1.94 ± 0.23 kg N<sub>2</sub>O ha<sup>−1</sup> yr<sup>−1</sup> in the grazing land (G0.7, G1.2, and G1.6). The annual mean N<sub>2</sub>O flux showed no significant differences between grazing treatments in 2013. However, there were significantly greater fluxes from the G0.7 treatment than from the G1.6 treatment in 2014, especially in the growing season. Over the two years, the soil N<sub>2</sub>O emission rate was significantly negatively correlated with soil water-filled pore space (WFPS) and dissolved organic carbon (DOC) content as well as positively correlated with soil available phosphorus (P). No relationship was observed between soil N<sub>2</sub>O emission rate and temperature or rainfall. Our results showed that the meadow soils acted as a source of N<sub>2</sub>O for most periods and turned into a weak sink of N<sub>2</sub>O later during the sampling period. Our results highlight the importance of proper grazing intensity in reducing N<sub>2</sub>O emissions from alpine meadow. The interaction between grazing intensity and N<sub>2</sub>O emissions should be of more concern during future management of pastures in Zoige Plateau.
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