Spectral reflectance library of algal, seagrass and substrate types in Moreton Bay, Australia.

Ten samples of each substrata were collected randomly and placed on a black background where each sample covered a homogenous 5 cm x 5 cm area. Radiance-reflectance measurements were collected using an Analytical Spectral Devices spectrometer (ASD VNIR), which recorded in the visible to infrared (400-1050 nm) wavelengths in 1024 bands (at 2 nm intervals, with a 7 nm Full-Width-Half Maximum power resolution), using a 68 field of view.
Upwelling radiance measurements (Lu) were obtained in sunlight by placing the spectrometer optics 15 cm vertically above the target. A SpectralonTM panel, approximating a 100% reflective Lambertian surface, was measured prior to each sample as a surrogate for down-welling irradiance (Ed). A radiance-reflectance signature was then calculated for each sample by dividing the target radiance by the Spectralon panel radiance (Lu/Ed). A mean spectral reflectance signature was produced by averaging 10 measurements for each target.
Spectral signatures include: seagrass and algae species, sand, mud and cyanobacteria (Lyngbya majuscula).