Fig. 1. Effects of different differential window scales on first derivative spectral response characteristics of reed leaves. (a) ω=5；(b) ω=10； (c) ω=15； (d) ω=20

Fig. 2. Effects of different differential window scales on correlation coefficient of reed leaf first derivative spectra and water content. (a) ω=5； (b) ω=10； (c) ω=15； (d) ω=20

Fig. 3. Effects of different differential window scales on the correlation coefficients of characteristic parameters. (a) Before smoothing; (b) after smoothing

Fig. 4. Effects of different differential window scales on the first derivative spectral response characteristics of reed leaves after smoothing. (a) ω=5； (b) ω=10； (c) ω=15； (d) ω=20