Towards a subtropical forest spectral library: spectra consistency and spectral separability

Abstract

To meet the demand of standard spectral information for the subtropical forest, a three-level spectral library including leaf spectra of 67 typical subtropical tree species was built using two spectrometers. Towards the spectra measured by different spectrometers, the spectra consistency was tested using one-way Analysis of Variance (ANOVA) and Jeffries-Matusita distance (J-M distance). The optimal band range and spectral dimension reducing method for subtropical tree species discrimination were assessed using J-M distance based on original spectra and derivative spectra on visible-near infrared band (VNIR, 350–1000 nm), shortwave infrared band (SWIR, 1000–2500 nm) and full band (350–2500 nm). It was found that: (1) the spectra measured by the two spectrometers were significantly different, but the derivative spectra were not; (2) the SWIR spectral band was optimal for separating these subtropical tree species; (3) the selection method outperformed transform method for reducing spectra dimension and separating subtropical tree species