油菜红边特征及其叶面积指数的高光谱估算模型  

Red edge characteristics and leaf area index estimation model using hyperspectral data for rape

作　　者：黄敬峰[1] 王渊[1] 王福民[1] 刘占宇[1] 

机构地区：[1]浙江大学农业遥感与信息技术应用研究所浙江大学农业信息科学与技术中心浙江省农业遥感与信息技术重点研究实验室,杭州310029

出　　处：《农业工程学报》2006年第8期22-26,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家"863"项目(2002AA130010-2-7);国家自然科学基金(40271078);科技部科技基础性工作专项(2003DEA2C010-13)

摘　　要：在2003～2004年油菜生长季，选用6个油菜品种，设置3个氮素水平的小区试验。在不同发育期同步测定油菜冠层的光谱反射率及对应叶片的叶面积指数。利用油菜冠层的光谱反射率数据提取红边参数，分析其变化规律，油菜叶面积指数与红边参数的相关性，估算结果表明：油菜冠层红边一阶导数光谱具有“双峰”现象，红边位置λred位于690～720nm之间，在油菜生长旺盛期间出现“红边平台”，前期有“红移”，后期有“蓝移”现象；叶面积指数与冠层光谱红边参数λred、Dλred、Sred之间在开花前存在显著相关，但开花后相关性不显著；利用开花前的红边参数可以估算油菜的叶面积指数，开花后的红边参数不能用于估算油菜的叶面积指数；最后建立了不同时期和开花前油菜叶面积指数的估算模型。The hyperspectral reflectances for rape canopies consisting of five cultivars and three nitrogen levels were measured in 2003～2004 growth period by an ASD FieldSpec Pro FR^TM. The corresponding leaf area indices were observed. The red edge parameters were extracted using the spectral reflectances of the rape canopies. There exist ‘two peak’ phenomena for the red edge of rape canopy spectra. The position of red edge λred is located between 690 nm and 720 nm. There is a ‘platform of red edge’ at the bloom stage of rape. The red edge shift was detected before flowering stage and blue shift after flowering stage. The relationship between red edge parameters and the leaf area index（LAl） was investigated during 8 development periods. Results were not consistently significant at any wavelengths. The leaf area indices were significantly correlative to the red edge parameters λred, Dλred and Sred of the canopy spectra before flowering stage, whereas the correlation coefficient showed very low r values that were in significant after flowering stage. So the red edge parameters of rape canopies before the flowering stage can be used to estimate the leaf area indices. The results for different stages, linear and non-linear regression models were compared and the optimum model for LAI before flowering stage was recommended.

关 键 词：油菜 高光谱遥感 红边参数 叶面积指数 相关分析 估算模型 

分 类 号：TP701[自动化与计算机技术—检测技术与自动化装置]