摘要
利用中红外光声光谱对土壤顶空氨气（NH3）浓度进行测定。结果表明,在动镜速率为0.16 cm/s,分辨率为4 cm^–1时获得的NH3光谱噪音较少且信号强度高。利用选定的参数采集不同浓度NH3光谱,其中位于900-1 000 cm^–1的特征吸收峰适于定量分析。分别选用该特征吸收的峰高、峰面积和第一主成分与NH3浓度进行回归建模,线性决定系数（R2）均达到0.9以上,表明三者都呈显著线性相关,中红外光声光谱可以用于快速测定土壤顶空中NH3浓度,这为土壤氮素循环研究提供了新手段。
Mid-infrared spectroscopy was used to measure the concentration of ammonia（NH3） in soil headspace. The result showed that a spectrum with stronger signal and less noise could be got when using the mirror velocity of 0.16 cm/s and the resolution of 4 cm^–1. The spectra of NH3 of different concentrations were obtained with the selected parameters, and the absorption peak within 900–1 000 cm^–1 was appropriate for quantitative analysis. Linear regression models were established between NH3 concentrations and peak height, peak area and the first principle respectively, and the corresponding decision coefficients（R^2） were greater than 0.9, indicating that all of them had significant linear correlation with NH3 concentration. The concentration of NH3 in soil headspace could be predicted quickly using mid-infrared spectroscopy combined with principal component regression.
出处
《土壤》
CAS
CSCD
北大核心
2014年第6期1017-1023,共7页
Soils
基金
国家自然科学基金项目(41130749)资助
关键词
中红外光声光谱
氨挥发
土壤顶空
主成分回归
Mid-infrared spectroscopy
NH3 volatilization
Soil headspace
Principal component regression
