中文摘要：

在青藏高原海北站,选择高寒矮嵩草草甸为研究对象,基于密闭箱-气相色谱法,探索高寒草甸N2O排放速率对模拟氮沉降、增水及其交互作用的响应特征。结果表明：氮沉降、氮沉降和增水交互作用可以极显著增加高寒草地土壤N2O排放速率（P〈0.01）,其分别增加了145.9%和193.5%。降水处理同样增加草地土壤N2O排放速率,但增加幅度仅为27.2%,未达到显著水平。高寒草地土壤N2O排放速率呈现较大的季节异质性,最高值出现于6月份,为197.0±8.8μg/m^2·h（交互作用处理样方）;最低值出现于生长季末期对照样方,约为3.1±0.23μg/m^2·h。

英文摘要：

The response characteristics of N2O emissions rate to simulated nitrogen deposition and adding precipitation,and its interaction in alpine meadow on the Tibetan Plateau were studied.This manipulation was carried out with a static chamber-gas chromatograph at Haibei station in Qinghai province.It was revealed that nitrogen deposition and the interaction significantly increased grassland N2O emission rates in the growing season.It increased by 145.9% and 193.5% than the control plot.Precipitation could raise soil N2O emission rates by 27.2% ,but it was not significantly different with the control plot.The highest emission rates reached 197.0±8.8μg/m^2·h in June（interaction plots of nitrogen deposition and precipitation adding）.However,the lowest value was about 3.1±0.23μg/m^2·h during the late growing season in the control plot.Thus,the emission characteristics of N2O emission showed significant temporal heterogeneity.