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以贵州省的玉米－油菜轮作田、大豆－冬小麦轮作和休耕地为研究对象，采用密闭箱－气相色谱法，对整个轮作期的土壤Ｎ２Ｏ释放进行观测，初步研究我国亚热带旱田的Ｎ２Ｏ释放特征．实验研究结果表明，３试验田Ｎ２Ｏ释放通量具有相同的规律性日变化形式，秋收作物达通量极大值的时间比越冬作物滞后２ｈ～３ｈ，气温是控制Ｎ２Ｏ通量日变化的主要环境因子：３试验田Ｎ２Ｏ释放通量（以Ｎ２Ｏ中的Ｎ计）分别在９．８１～４３３．１１，４．００～１８０．４１和９．７４～２８２．００μｇ·ｍ － ２·ｈ－ １，高于我国水田和北方旱田的Ｎ２Ｏ释放通量；进一步分析表明，３试验田Ｎ２Ｏ释放通量具有相同的季节变化模式，Ｎ２Ｏ 释放峰受降雨事件的直接影响，Ｎ２Ｏ通量与降雨量和土壤湿度间有显著的正相关性，而与温度的关系不明显
In this study, the rotation of maize-rapeseed crop rotation, soybean-winter wheat rotation and fallow cropland in Guizhou Province were studied. The closed-chamber gas chromatography was used to observe the soil N2O release during the whole crop rotation period, and to study the N2O release characteristics in subtropical dryland in China. The experimental results show that the N2O flux has the same regular diurnal variation pattern in three experimental fields. The maximum flux of autumn harvest reaches the lag of 2 h ~ 3 h compared with that of the overwintering crop. The temperature is the main environmental factor controlling diurnal variation of N 2 O flux : 3 The N2O fluxes (calculated as N in N2O) in the experimental field ranged from 9.81 to 433.11, from 4.00 to 180.41 and from 9.74 to 282.00 μg · m -2 · h -1 respectively N2O flux in paddy fields of China and northern China. Further analysis showed that N2O fluxes had the same seasonal variation pattern in the three experimental plots. The N2O release peak was directly affected by rainfall events. N2O fluxes were correlated with rainfall and soil moisture Significant positive correlation, while the relationship with the temperature is not obvious