ABoVE: Tundra Plant Leaf-level Spectral Reflectance
Schematic of FluoWat leaf clip operation for measuring leaf reflectance, transmittance, and upward and downward fluorescence (SIF). The leaf is placed in the clip and illuminated through the open port (A). Reflected and transmitted radiance are measured by attaching a fiber optic cable from the spectrometer to the top or bottom of the clip. To measure fluorescence spectra a low pass filter is placed across the illumination port (B). Two filters are applied in sequence, they block incident wavelengths above 650 nm and 700 nm, therefore any radiance measured in the longer wavelengths can come only from fluorescence.