Abstract:

Abstract：In this study，we used ‘Xiushui 110’ to create the diagnostic models, and then used ‘Xieyou 9308’ to test. The results indicate that the first derivative spectra are significantly correlated to nitrogen content. The highest squared multiple correlation coefficients R2 =0.74. In the best predicting model of nitrogen content, R2 =0.84. Comparing with the first derivative transmittance spectra, we build three indices, including blue edge transmittance spectra nitrogen index (BETNI), yellow edge transmittance spectra nitrogen index (YETNI) and red edge transmittance spectra nitrogen index (RETNI), calculated from three edge specific wavebands respectively. The significant correlations (P<0.01) between the nitrogen content and these indices are more obvious than that between the nitrogen content and single leaf transmittance spectra of specific wavebands. YETNI610, YETNI630, YETNI643, YETNI652, and RETNI are better predictors for nitrogen content than others. From this preliminary analysis, it is observed that the transmittance spectra nitrogen indices YETNI570, YETNI592, and RETNI are the best predictors to estimated nitrogen content.