不同施肥条件下烟草冠层光谱特征与叶绿素、叶面积指数的关系

Relationship of Spectral Characteristics with Chlorophyll and Leaf Area Index in Flue-cured Tobacco Leaf

为快速、无损、准确地估测烟草叶绿素含量和叶面积指数,获取烟草长势信息,通过不同条件施氮试验,采用ASDField HH光谱仪,分析不同处理烤烟冠层光谱特征,同时运用相关、回归等统计方法,研究了不同施氮条件下冠层高光谱遥感特征与叶绿素含量和叶面积指数的相关性。结果表明,不同施肥条件下烟草冠层光谱反射率差异显著,经筛选,绿波段植被指数(GNDVI)与叶绿素含量和叶面积指数关系显著,建立的回归方程的R2分别为0.436和0.568,均达到显著水平。因此,可利用建立的估测模型对烟草生长状况进行快速测定,及时指导烟田施肥和采取合适的栽培管理措施。

This study aims to estimate the chlorophyll content and leaf area index （LAI） of tobacco with rapid, harmless and accurate methods to obtain the information on its growth vigor and to provide technological support for the management of cultivation. Under different fertilization conditions, we analyzed the spectral characteristics of tobacco canopy treated in different ways through ASD Field HH spectrometer, and studied the correlation of hyperspectral characteristics with chlorophyll content and LAI in tobacco canopy at nitrogen fertilizer of different levels through relevant statistical methods （such as correlation analysis and regression etc.）. Under different fertilization conditions, the spectral reflectance of tobacco canopy was significantly different, normalized different vegetation index （NDVI （green） was significantly related to chlorophyll content and LAI, and the regression coefficient of established regression equation, associated probability and determination coefficient were all reaching to significant level. Therefore, the growth state of tobacco could be quickly investigated through this established estimation model, so as to control the fertilization of tobacco field and take suitable planting management measures on time.