Estimating the fractional abundance of coral reef benthic compositions using linear spectral unmixing

Abstract

The present work is focused on providing the application of linear spectral unmixing technique to Landsat-8 images of Operational Land Imager (OLI) bands in coral reef environment at Gulf of Mannar (GoM) islands along the coast of Tamilnadu, India. The spectral characteristics of benthic compositions namely sand, seagrass, branched corals and mass corals in the GoM are recorded in-situ using RAMSES-TriOS Hyperspectral radiometer and the signatures recorded from in-situ have been used as input for linear spectral unmixing technique. The results of linear spectral unmixing provide the fractional abundances of coral reef benthic communities in the Islands of GoM region. Such maps can be used to characterize the landscape structure and composition of reefs, which can in turn be linked to environmental and human impacts. This kind of approaches is cost-effective and acts as a valuable tool for the evaluation and periodical monitoring of coral reef community.