中红外光谱土壤有机质含量估测研究进展

Research progress on prediction of soil organic matter content by mid-infrared spectroscopy

中红外光谱波段(2.5~25μm)对土壤有机质内部分子振动高度敏感,基于中红外光谱技术的土壤有机质含量估测是土壤学科新兴的研究方向和热点。文章采用文献综述的方法,全面总结了土壤有机质含量中红外光谱估测方法的发展和应用,简述了中红外光谱响应与土壤有机质分子结构的相关性研究,对比分析了室内台式、手持式和机载中红外光谱设备估测土壤有机质含量的优势和局限性,比较分析了中红外、近红外、可见光-近红外光谱及其光谱组合估测土壤有机质含量的模型精度和稳定性,总结分析了基于中红外光谱技术的土壤有机质含量建模方法研究进展,以及土样制备、光谱数学变换、敏感波段选择等前处理对土壤有机质含量估测精度的影响研究,最后提出了土壤有机质含量中红外光谱估测存在的问题及发展趋势,为土壤有机质含量的测定工作提供参考。

The mid-infrared spectrum(2.5 ~ 25 μm)is highly sensitive to the internal molecular vibration of soil organic matter.The prediction of soil organic matter content based on mid-infrared spectroscopy technology is an emerging research direction and hotspot in soil science.The paper comprehensively summarizes the development and application of soil organic matter content prediction methods based on mid-infrared spectroscopy by means of literature review.Firstly,the paper briefly reviewed the research on the correlation between mid-infrared spectroscopy and soil organic matter molecular composition.The advantages and limitations of indoor desktop,handheld and airborne mid-infrared spectroscopy equipment for prediction of soil organic matter content,coupled with the accuracy and stability of mid-infrared,near-infrared,visiblenear-infrared spectroscopy and their spectral combinations are compared and analyzed.Secondly,the paper summarizes and analyzes the research progress of soil organic matter content modeling methods based on mid-infrared spectroscopy,as well as the effects of pre-processing such as soil sample preparation,spectral mathematical transformation,and selection of sensitive bands on the accuracy of soil organic matter content prediction.Finally,the problems and development trends in the prediction of soil organic matter content based on mid-infrared spectroscopy are put forward in order to provide references for measurement of soil organic matter content.