基于高光谱特征参数的樟树叶绿素含量的估算模型研究

Study on modeling chlorophyll content of camphor by characteristic variables of hyperspectra

叶绿素在植物的生理生态过程中非常重要,而高光谱遥感的快速发展使得定量估算植被叶绿素含量成为可能。采用美国ASD公司生产的野外光谱辐射仪测量樟树幼林的叶片光谱,对观测叶片进行了同步叶绿素含量的测定。利用基于光谱位置变量的分析方法,分析樟树叶片光谱与叶绿素含量之间的关系。结果表明:樟树幼林叶绿素含量与Db、Rg、Rg/Ro、(Rg-Ro)/(Rg+Ro)之间的相关程度很高,相关系数达到极显著检验水平;通过建立特征参数与叶绿素含量之间的估算模型,并进行精度检验,得出了叶绿素含量估算的高光谱模型为y=exp〔1.356+(-361.973)Db〕。说明利用高光谱遥感数据可以估测樟树幼林的叶绿素含量。

Chlorophyll is vital in the physiological processes of plants.The fast development of hyperspectral remote sensing make it possible to estimate the vegetation chlorophyll content quantitatively.In this study,young camphor was selected as interesting object,and the spectral reflectance of foliage was measured by ASD HandHeld Spectrometer in field.The chlorophyll contents were measured in lab at the same time.The relationships between the spectral reflectance of foliage and chlorophyll contents were analyzed by hyperspectrum position variables of analysis method.The results showed that there were relationships between the chlorophyll content and the characteristic variables of hyperspectra,such as Db,Rg,Rg/Ro,（Rg-Ro）/（Rg＋Ro）.Several estimation models between the characteristic variables of hyperspectra and chlorophyll content were built.The fittest hyperspectral estimation models of chlorophyll content was kept after precision tested which was following：y=exp（1.356＋（-361.973）×Db）.These results suggested that the hyperspectral estimation models could be used to estimate the leaf chlorophyll content of young camphor.