内蒙古河套灌区盐碱土壤N2O排放特征

选择内蒙古河套灌区强度盐碱土壤S₁[电导率（EC）2.60dS/m]和轻度盐碱土壤S₂[电导率（EC） 0.74dS/m]为研究对象，2014~2016年，利用静态箱法3年野外原位观测试验，研究盐碱土壤氧化亚氮（N₂O）排放通量.结果表明：2种不同盐碱程度土壤N₂O排放每年均存在显著差异，轻度盐碱土壤N₂O累积排放量低；随EC升高，土壤盐碱程度加重，土壤N₂O累积排放量升高.2014~2016年作物生长季（4~11月）轻度盐碱土壤N₂O累积排放量分别为180.6，167.6，118.2mg/m²；强度盐碱土壤N₂O累积排放量比轻度盐碱土壤分别增加19%、26%和45%，修复盐碱土壤成为减缓盐碱土壤N₂O累积排放的重要农艺措施.

N2O emissions from saline-alkaline soil with different saline-alkaline levels in the Hetao Irrigation District of Inner Mongolia,China

It were chosen for high saline-alkaline soil, S₁[electrical conductivity (EC) 2.60dS/m] and low saline-alkaline soil, S₂[electrical conductivity (EC) 0.74dS/m] in Hetao Irrigation District of Inner Mongolia. The static box method was used in field in-situ observation test for 3year. A 3-yr study was conducted with sunflower crops in intensively managed saline-alkaline soils cropping systems in northeastern China to examine the effects of salt and alkali on N₂O emissions. Results indicated that high saline-alkaline soil significantly increased N₂O emissions with obvious differences as compared with low saline-alkaline soil. The accumulative emissions of N₂O during the 3-year observation period were estimated at 180.6mg/m², 167.6mg/m² and 118.2mg/m² for the low saline-alkaline soil. Compared with low saline-alkaline soil, the high saline-alkaline soil significantly increased the accumulative emissions of N₂O by 19%, 26% and 45% from 2014 to 2016, respectively. Our findings suggest that mitigating N₂O emissions on saline-alkaline soil can be achieved by remediating saline-alkaline soil.