HYPERSPECTRAL DISCRIMINATION AND SEPARABILITY ANALYSIS OF CORAL REEF COMMUNITIES IN REDANG ISLAND
Loading...
Date
2009
Journal Title
Journal ISSN
Volume Title
Publisher
Journal of Sustainability Science and Management
Abstract
An assessment ofthe spectral separability between different reefspecies was undertaken
using underwater hyperspectral measurements. In-situ upwelling and downwelling radiances were
collected for eight substrates of Redang Island reef communities, including five corals, algae and
sediments. Underwater spectral measurements ranging from 350 to 800 nm were taken 0.25 m
above the substrate using a Satlantic HyperOCR spectroradiometer. Hyperspectral retlectance and
derivative datasets were analysed using the stepwise discriminant function analysis to determine the
best discriminating wavelength for each species at Chagar Hutang, Redang Island. Results showed
that major reflectance features of reef species were identified by two distinctive peaks at 575 and
610 nm. Stepwise wavelength selection revealed that reefspecies could be well-distinguished using
the derivative dataset (15 non-contiguous wavelengths) compared to hyperspectral reflectance (4
non-contiguous wavelengths). These preliminary results are encouraging and demonstrated the
possibility to spectrally distinguish different types of coral reef community using hyperspectral
remote sensing.
Description
Keywords
Coral reef, hyperspectral, reflectance, discrimination, remote sensing