农作物冠层光谱分析及反演技术综述

农作物的冠层光谱反射率与作物的氮含量、叶绿素含量及叶面积指数等参数之间具有很强的相关性，通过对作物冠层光谱进行分析可反演出作物的生物物理参数，并应用在长势分析、产量预测、病虫害预警等领域。本文首先阐述了作物冠层反射率采集方法，对地面、机载及遥感卫星3个采集层面的优缺点进行了对比；其次给出了植被指数构建原理及常用植被指数，分析了物理模型反演法和统计反演法的复杂度和性能；最后提出了农作物冠层光谱分析及反演技术的下一步发展方向及面临的挑战。

Review on crop canopy spectral analysis and retrieval

The crop canopy spectral reflectance has a strong correlation with the biological and physical parameters of crops such as the leaf nitrogen content, the chlorophyll content and the leaf area index. The biological and physical parameters can be retrieved by crop canopy spectral analysis, and applied to the field of growth analysis, yield prediction, pest and disease warning and so on. Firstly, three kinds of canopy reflectance acquisition methods based on ground, airborne and space-borne spectral meters are expounded separately, whose advantages and disadvantages are compared. Secondly, the principle of vegetation index construction is given, and the complexity and performance of physical model based retrieval and statistical retrieval methods are analyzed. Finally, the future and challenges of crop canopy spectral analysis and retrieval are suggested.