基于物候特征的植物光谱识别方法研究  

Plant Spectral Discrimination Based on Phenological Features

作　　者：张磊 赵健龙[2] 贾坤[3] 李晓松[1] 

机构地区：[1]中国科学院遥感与数字地球研究所中国科学院数字地球重点实验室,北京100101 [2]中国地质大学地球科学与资源学院,北京100083 [3]北京师范大学地理学与遥感科学学院,北京100875

出　　处：《光谱学与光谱分析》2015年第10期2836-2840,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金面上项目(41371361);北京市科技计划项目(Z141100000614001)资助

摘　　要：光谱分析对于植物识别特征与机理研究具有重要意义,长期以来在植被光谱的叶绿素吸收特征、水分吸收特征、红边效应、光谱波形参数提取、波形转换、以及植被叶面结构和化学组份对光谱的影响方面进行了大量研究,而在植物因季节变化引起的叶面结构、叶绿素、叶面积指数变化而产生的光谱变化研究较少。通过开展对不同生活型、叶面结构与大小、物候特征的11类植物季节生长过程的地物光谱观测,提取植物的归一化植被指数NDVI、包络线去除后的绿波段最大光谱吸收深度、红波段最大光谱吸收深度参数,对该参数时间过程曲线的均值、变幅、斜率进行分析,研究植物生长期和成熟期特征参数的植物光谱可分性研究。提出了植被光谱区分度的参数运算方法,利用该参数进行植被识别能力分析。结果表明:植物生长过程的光谱特征比成熟期的光谱特征更容易区分。在相同参数对比中,生长期植物区分度比成熟期区分度高出三个点。在植物生长过程中,总体上植被的季节变幅区分度>斜率区分度>均值区分度,而对于NDVI参数季节变化,植物季节斜率区分度最大。所以利用植物的季节NDVI斜率、绿波段最大光谱吸收深度的季节变幅、红波段最大光谱吸收深度的季节变幅进行植物的识别效果最佳。Spectral analysis plays asignificant role onplant characteristic identification and mechanism recognition ,there were many papers published on the aspects of absorption features in the spectra of chlorophyll andmoisture ,spectral analysis onvege‐tation red edge effect ,spectra profile feature extraction ,spectra profile conversion ,vegetation leaf structure and chemical com‐position impacts on the spectra in past years .However ,fewer researches issued onspectral changes caused by plant seasonal changes oflife form ,chlorophyll ,leaf area index .This paper studied on spectral observationof 11 plantsof various life form , plant leaf structure and its size ,phenological characteristics ,they includedeciduous forest with broadvertical leaf ,needleleafever‐green forest ,needleleafdeciduous forest ,deciduous forest with broadflat leaf ,high shrub with big leaf ,high shrub with little leaf ,deciduous forest with broad little leaf ,short shrub ,meadow ,steppe andgrass .Field spectral data were observed with SVC‐HR768 （Spectra Vista company ,USA） ,the band width covers 350-2 500 nm ,spectral resolution reaches 1-4 nm .The features of NDVI ,spectral maximum absorption depth in green band ,and spectral maximumabsorption depth in red bandwere measured after continuum removal processing ,the mean ,amplitude andgradientof thesefeatures onseasonalchange profilewere analyzed ,meanwhile ,separability research on plant spectral feature of growth period and maturation period were compared .The paper presents a calculation method ofseparabilityof vegetation spectra which consider feature spatial distances .This index is car‐ried on analysis of the vegetation discrimination .The results show that ：the spectral featuresduring plant growth periodare easier to distinguish than them during maturation period .With the same features comparison ,plant separabilityof growth period is 3 points higherthan it during maturation period .The overall separabilityof vegetation spectrumfeatures shows seasonal amplitude〉seasonal gra

关 键 词：植物识别 物候特征 包络线去除 最大光谱吸收深度 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置]