A Preliminary Research on Dominant Species Identification of Red Tide Organism by Airborne Hyperspectral Technique

摘要

The fine spectra data of red tide can be obtained by airborne hyperspectral red tide monitor. The identification of dominant species of red tide organism by airborne hyperspectral is of great significance for the red tide monitoring. By making spectral angle analysis and calculating the angle between reflectance of hyperspectral image pixel and that of reference spectra, the similarity of spectra of dominant species to be identified to reference spectra can be determined, and the species of red tide organism whose spectrum makes a smallest angle with the spectra of hyperspectral image pixel is chosen as dominant one. Reference spectra was measured from the red tide water body during two mesocosm ecosystem experiments and its surrounding water body in August 2002, and the spectra to be identified is the hyperspectral data collected from Bayuquan water body in the Liaodong Bay. By means of spectral angle analysis, red mesodinium rubrum is identified as the dominant species in the red tide on August 25, 2001, which is verified by the synchronous measured data at sea. It is shown from the study results that the airborne hyperspectral approach to identify the dominant species of red tide is feasible, and will offer valuable service for red tide monitoring.