The Change of Spectral Signatures of Beech and Spruce by Forest Damage.

Abstract

To improve our understanding of spectral signature changes by forest damage and to optimize damage identification and separation high resolution spectroradiometer measurements of tree components were performed in the laboratory, simulating scanner data acquisition. The measurements of healthy and damaged beech and spruce branches proved the influence of primary effects of damage on spectral reflectance in the 0.49-2.50 ym region. In the visible discoloration influences largely the course of spectral signatures, causes red shift of the reflection peak and a variation of shape at the beginning to the NIR plateau. In the IR reflectance decreases with increasing damage level for beech. For spruce branches the NIR plateau level reduces alsomwith increasing damage. For wavelengths greater 1.4 ym the curves raise with higher damage level.