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Significant advances have been made in remote sensing methods that support accurate and repeatable methods for mapping the composition, structure and condition of submerged, coastal, coral reef and marine environments. One of the newer developments in substrate and benthic cover mapping are algorithms which have been developed using spectral reflectance libraries of the cover types composing the bottom of these environments. The spectral libraries are used either to constrain the approach taken or as an input parameterisation tool for mapping specific features. As a water column lies between the substratum, benthos and the air-water interface, any complete shallow aquatic water habitat spectral library for remote sensing purposes also needs to consider the apparent optical properties of the water column. Substratum mapping projects using these spectral data sets in a range of environments around the world demonstrate the necessity of appropriate spectral reflectance measurements.

In order to assess the estuarine, coastal, coral reef and marine environments extent from airborne or satellite imagery parameterized by in situ spectral reflectance libraries, a set of standards for the capture, storage and use of these spectral signature files needs to be established. The shallow water environment creates unique challenges for systematic and standardised underwater or above-water spectral reflectance measurements due to variations in solar angle, atmospheric conditions, sea surface conditions, currents, water column optical properties, etc. Globally useful spectral field data will need to include complete metadata (what is measured …