The Relationship between the Leaves' Relative Water Content and Spectral Signatures of Cinnamomum camphora

• Main Authors: Hui-Lin Wen, 溫慧霖
• Other Authors: Chinsu Lin
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/98561710753138177576

碩士 === 國立嘉義大學 === 森林暨自然資源學系研究所 === 96 === This study analyzes the relationship between the water content and spectral reflectance of the Cinnamonum camphora leaves by using hyperspectral technique and measure the water contents of the tree’s leaves and the corresponding spectral reflectance to establish the regression models with the correlated material. Results indicated that reflectance was negatively related to relative water content (RWC), while regression model showed that R2 value ranges from 0.65~0.80 for green and red bands with the spectral range of 515~560 nm and 600~740 nm, respectively. The results also showed that there exists a high correlation between RWC and reflectance of tree’s leaves (R2>0.95) in two SWIR regions (1320~1650 and 1840~2240 nm). Pearson’s correlation showed the RWC was negatively correlated with the reflectance of wavelength longer than 900nm and the correlation coefficient can reach -0.7, and the value can be even higher -0.9 in SWIR region. By multiple linear regressions for choose spectral signatures, the accuracy of proposed model for estimating water status of tree leaves can reach 95%. Studies had proved the absorption of visible band was controlled by the plant pigment, however, the variation of RWC can be also represented by the visible band with the ability of 81.8% in this study.