氧化亚氮（N2O）的过量排放会对臭氧层造成破坏, 合理施肥和采取减排措施对减缓温室效应具有重要的现实意义。 本文利用FTIR光谱法研究了施肥和水分对白菜地土壤排放N2O的影响。 为了提高系统的灵敏度, 我们利用多个反射镜加长了光程。 通过比对施肥前后N2O红外光谱和NIST谱库N2O红外光谱, 最终选取2 160～2 225 cm-1作为定量计算N2O的特征波段。 研究发现, 施肥和水分能促进白菜地土壤N2O气体排放, 这为农田N2O的减排和减缓温室效应提供了理论依据。 最后, 还研究了施肥后土壤N2O的昼夜排放规律, 结果表明, N2O白天的排放量高于晚上, 通过和前人研究结果对比, 验证了此方法的可行性。 本文研究证实, 基于长光程的FTIR光谱法是一种测量土壤排放N2O气体规律的快速有效方法, 它可以对施肥后的白菜地土壤N2O气体排放进行测量, 相对其他传统测量方法具有高速、 简便等优势。

The excessive emission of N2O (Nitrous oxide) will destroy the ozone layer, reasonable fertilization and adopting measures of emission reduction of N2O are of great significance to slowing down the greenhouse effect. The article studied the impact of fertilization and water on the emission of N2O from the cabbage farmland using FTIR spectrometry. To enhance the sensitivity of the measuring system, we used multi-reflecting mirrors to increase the optical pathlength. By comparing the infrared spectra between the before and after fertilizer application and the NIST spectral library, finally, the band at 2 160～2 225 cm-1 was chosen as the spectral characteristics band of quantitative calculation of N2O through analyzing. The research found that fertilization and water could promote the emission of N2O from the cabbage farmland soil, which could supply theory bases for emission reduction of N2O and slowing down the greenhouse effect. Finally, we also studied the diurnal emission rules of N2O from the fertilized soil; the results showed that the emission of N2O was lower at night and the results were compared with that of previous’ studies, which verifies the feasibility of this method. The results proved that FTIR with long optical path was a rapid and effective method to measure the emission rules of N2O from the cabbage farmland soil, which can measure the gas emissions of N2O from the fertilized cabbage farmland soil and compared with other traditional measuring methods, it had the advantages such as rapidness and convenience.