基于改进距离投影比值指数的植被冠层水分反演  

Inversion of vegetation canopy water content by improved distance projection ratio index

作　　者：雷俊杰 杨武年[1] 杨鑫 李红 LEI Junjie;YANG Wunian;YANG Xin;LI Hong(College of Earth Science,Chengdu University of Technology,Chengdu 610059,China;Shangqiu Normal University,Shangqiu 476000,China;Henan Engineering Technology Research Center of Ecological protection and management,Shangqiu 476000,China;Chongqing vocation Institute of engineering,Chongqing 402260,China)

机构地区：[1]成都理工大学地球科学学院,四川成都610059 [2]商丘师范学院,河南商丘476000 [3]河南省黄河故道生态保护与治理工程技术研究中心,河南商丘476000 [4]重庆工程职业技术学院,重庆402260

出　　处：《人民长江》2021年第9期113-118,共6页Yangtze River

基　　金：国家自然科学基金项目(41671432);重庆市教育委员会科学技术研究项目(KJQN201803402);黄河故道生态保护和高质量发展项目(2021KYFZ06)。

摘　　要：针对两个特征波段组成的植被指数存在的饱和以及植物类型依赖问题,利用便携式地物光谱仪(analytical spectral devices,ASD)和哨兵2号多光谱卫星(Sentinel 2,S2)数据,使用改进的距离投影比值指数(improved distance projection ratio index,DPRI2)建立新叶片等效水厚度(leaf equivalent water thickness,LEWT)反演模型,进而反演冠层等效水厚度(canopy equivalent water thickness,CEWT)。研究表明:①R语言随机森林(random forest,RF)算法可减少特征波段选取过程中人为因素;②DPRI2结构简单,能充分反映特征波段之间角度、距离、投影三者组合关系,有利于提高LEWT、CEWT反演精度;③DPRI2不受植被类型限制,适用于具有多种植被类型的研究区CEWT反演。通过遥感手段监测CEWT,有利于探究植被在区域水文循环中的调控机制,以及科学评估区域水资源储量。To solve the problem of saturation and plant type dependence of vegetation index composed of two feature bands,this study used analytical spectra devices(ASD)and Sentinel 2 multispectral satellite(S2)data to establish a new leaf equivalent water thickness(LEWT)inversion model by using the improved distance projection ratio index(DPRI2),and then inverted the canopy equivalent water thickness(CEWT).The results show that:①Random forest(RF)algorithm of R language can reduce the human factors in the selection of feature bands.②The structure of DPRI2 is simple,which can fully reflects the combination of angle,distance and projection between feature bands,and is conducive to improving the inversion accuracy of LEWT and CEWT.③DPRI2 cannot be limited by vegetation types and is suitable for CEWT inversion in the study area with multiple vegetation types.Monitoring CEWT by remote sensing is helpful to exploring the regulation mechanism of vegetation in regional hydrological cycle,and to scientifically evaluating regional water resources reserves.

关 键 词：植被水文效应 冠层等效水厚度 遥感反演 高光谱分析 多光谱卫星 特征波段 R语言 

分 类 号：TP75[自动化与计算机技术—检测技术与自动化装置] TP79[自动化与计算机技术—控制科学与工程]