Salas EAL, Henebry GM (2009) Area between peaks feature in the derivative reflectance curve as a sensitive indicator of change in chlorophyll concentration. GIScience and Remote Sensing 46(3): 315-328.
Abstract: Vegetation spectral features can detect chlorophyll concentrations. Two key spectral features evident in the first derivative (FD) of reflectance constitute the two main peaks: one located around 685-705 nm and the other near 710-725 nm. We propose that the area between peaks (ABP) can be used as a sensitive indicator of changes in the photosynthetic pigments at leaf level and demonstrate it using a high-spectral-resolution dataset of maize leaves collected by Gitelson and coworkers (2005). We find significant high positive correlations (r^2 > 0.90) between chlorophyll concentrations and both the ABP and its continuum length feature.