Application of Fractional Differential Calculation in Pretreatment of Saline Soil Hyperspectral Reflectance Data

Figure 6

between salt content and raw spectral reflectance for area A. (a) 0–0.4-order differential. (b) 0.6–1^st-order differential. (c) 1.2–1.4-order differential. (d) 1.6–2^nd-order differential.

(a)

(b)

(c)

(d)