A shadow- eliminated vegetation index (SEVI) for removal of self and cast shadow effects on vegetation in rugged terrains

作     者：Hong Jiang Sen Wang Xiaojie Cao Chenghai Yang Zhaoming Zhang Xiaoqin Wang 

作者机构：Key Laboratory of Spatial Data Mining&Information Sharing of MOEand Fujian Spatial Information Research CenterFuzhou UniversityFuzhouPeople’s Republic of China Aerial Application Technology Research UnitUSDAAgricultural Research ServiceCollege StationTXUSA Chinese Academy of SciencesInstitute of Remote Sensing and Digital EarthBeijingPeople’s Republic of China 

出 版 物：《International Journal of Digital Earth》 (国际数字地球学报（英文）)

年 卷 期：2019年第12卷第9期

页      面：1013-1029页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 07[理学] 

基　　金：China National Key Research and Development Plan[grant number 2017YFB0504203] China Scholarship Fund[grant number 201706655028] Natural Science Foundation of Fujian Province[grant number 2017J01658] 

主　　题：Vegetation indices shadoweliminated vegetation index(SEVI) terrain shadow effect self shadow cast shadow 

摘      要：The effect of terrain shadow, including the self and cast shadows, is one ofthe main obstacles for accurate retrieval of vegetation parameters byremote sensing in rugged terrains. A shadow- eliminated vegetation index(SEVI) was developed, which was computed from only red and nearinfrared top-of-atmosphere reflectance without other heterogeneous dataand topographic correction. After introduction of the conceptual modeland feature analysis of conventional wavebands, the SEVI was constructedby ratio vegetation index (RVI), shadow vegetation index (SVI) andadjustment factor (f (Δ)). Then three methods were used to validate theSEVI accuracy in elimination of terrain shadow effects, including relativeerror analysis, correlation analysis between the cosine of solar incidenceangle (cosi) and vegetation indices, and comparison analysis between SEVIand conventional vegetation indices with topographic correction. Thevalidation results based on 532 samples showed that the SEVI relativeerrors for self and cast shadows were 4.32% and 1.51% respectively. Thecoefficient of determination between cosi and SEVI was only 0.032 and thecoefficient of variation (std/mean) for SEVI was 12.59%. The results indicatethat the proposed SEVI effectively eliminated the effect of terrain shadowsand achieved similar or better results than conventional vegetation indiceswith topographic correction.