20 C.-H.Xiao et al 0.50 0.50 =0.40 A Jingdong 0.40 0.30 o. A Zhongyou9507 0.20 0.20 0.10 0.00 0.00 300 300 800130018002300 39 二30 -90 —120 10 二180 —30 Fig.3.Spectra of removing the forth leaf layer at different angles for Jingdong8 and Zhongyou9507 wheat .60 0.40 Jingdong8 Zhongyou9507 0.30 0.00 300 300 2300 800 230 Fig.4.Spectra of removing different leaf layers at 60angles for Jingdong8 and Zhongyou9507 Comparing the direction spectral characteristic of the two wheat canopies,the respons of月 v angles more signif t tha that of Zhonyou5thlewayebands:the mat reeetivity o Jingdong8 was 31%higher than that of Zhongyou9507 at 350-700nm and 22.4% higher at 800-1300nm. The spectral curve of doing away with different leaves at the 60 view angle showed that the leaf influenced the curve of visible and near infrared wavebands(Fig.4).The change for Jingdong8 was more significant than for Zhongyou9507;the spectra reflectivity of Jingdong&was 11.higher than that of 350-70 and 26.8%highe at800-130 To further analyze the relation between canopy spectra and leaves,we selected six spectral reflectivities at 450,550,670,980,1090,1200nm. 3.2 Analysis of Spectral Reflectivity of Leaf Layers at Different View Angles As shown in Fig.5,for Jingdong8.the spectral reflec imila r with the if layer remova ILLCreduced the refetivity.The changes in reflectivity at550nm were more 20 C.-H. Xiao et al.            :DYHOHQJWKQP 5HIOHFWLRQ e e e e e e e            :DYHOHQWKQP 5HIOHFWLRQ e e e e e e e Jingdong8 Zhongyou9507 Fig. 3. Spectra of removing the forth leaf layer at different angles for Jingdong8 and Zhongyou9507 wheat                 :DYHOHQJWKQP 5HIOHFWLRQ ,//& ,//& ,//& ,//& ::& (/&            :DYHOHQJWKQP 5HIOHFWLRQ ,//& (/& ,//& ,//& ,//& ::& Jingdong8 Zhongyou9507 Fig. 4. Spectra of removing different leaf layers at 60°angles for Jingdong8 and Zhongyou9507 Comparing the direction spectral characteristic of the two wheat canopies, the spectral response of Jingdong8 with different view angles was more significant than that of Zhongyou9507 at visible and near infrared wavebands; the max reflectivity of Jingdong8 was 31% higher than that of Zhongyou9507 at 350-700nm and 22.4% higher at 800-1300nm. The spectral curve of doing away with different leaves at the 60° view angle showed that the leaf influenced the curve of visible and near infrared wavebands (Fig.4). The change for Jingdong8 was more significant than for Zhongyou9507; the spectral reflectivity of Jingdong8 was 11.2% higher than that of Zhongyou9507 at 350-700nm and 26.8% higher at 800-1300nm. To further analyze the relation between canopy spectra and leaves, we selected six spectral reflectivities at 450, 550, 670, 980, 1090, 1200nm. 3.2 Analysis of Spectral Reflectivity of Leaf Layers at Different View Angles As shown in Fig.5, for Jingdong8, the spectral reflectivity of the whole canopy was similar with the leaf layer removal treatment, ILLC-4; doing away with ELC and ILLC-1 reduced the reflectivity. The changes in reflectivity at 550nm were more