A new vegetation index combination for leaf carotenoid-tochlorophyll ratio: minimizing the effect of their correlation  

作　　者：Chunmei He Jia Sun Yuwen Chen Lunche Wang Shuo Shi Feng Qiu Shaoqiang Wang Torbern Tagesson 

机构地区：[1]Hubei Key Laboratory of Regional Ecology and Environmental Change,School of Geography and Information Engineering,China University of Geosciences,Wuhan,People’s Republic of China [2]Department of Physical Geography and Ecosystem Science,Lund University,Lund,Sweden [3]State Key Laboratory of Information Engineering in Surveying,Mapping,and Remote Sensing,Wuhan University,Wuhan,People’s Republic of China [4]International Institute for Earth System Science,Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology,Nanjing University,Nanjing,People’s Republic of China [5]Department of Geosciences and Natural Resource Management,University of Copenhagen,Copenhagen,Denmark

出　　处：《International Journal of Digital Earth》2023年第1期272-288,共17页国际数字地球学报（英文）

基　　金：supported by the National Natural Science Foundation of China(42001314);the Open Research Fund of the State Laboratory of Information Engineering in Surveying,Mapping,and Remote Sensing,Wuhan University(grant number 20R02);Torbern Tagesson was additionally funded by the Swedish National Space Agency(SNSA 2021-00144);FORMAS(Dnr.2021-00644).

摘　　要：The ratio of leaf carotenoid to chlorophyll(Car/Chl)is an indicator of vegetation photosynthesis,development and responses to stress.However,the correlation between Car and Chl,and their overlapping absorption in the visible spectral domain pose a challenge for optical remote sensing of their ratio.This study aims to investigate combinations of vegetation indices(VIs)to minimize the influence of Car-Chl correlation,thus being more sensitive to the variability in the ratio across vegetation species and sites.VIs sensitive to Car and Chl variability were combined into four candidates of combinations,using a simulated dataset from the PROSPECT model.The VI combinations were then tested using six simulated datasets with different Car-Chl correlations,and evaluated against four independent datasets.The ratio of the carotenoid triangle ratio index(CTRI)with the red-edge chlorophyll index(CIred-edge)was found least influenced by the Car-Chl correlation and demonstrated a superior ability for estimating Car/Chl variability.Compared with published VIs and two machine learning algorithms,CTRI/CIred-edge also showed the optimal performance in the fourfield datasets.This new VI combination could be useful to provide insights in spatiotemporal variability in the leaf Car/Chl ratio,applicable for assessing vegetation physiology,phenology,and response to environmental stress.

关 键 词：Leaf carotenoids content leaf chlorophyll content PROSPECT model ratio of Car to Chl vegetation index 

分 类 号：Q94[生物学—植物学]