EVALUATION OF LANDSAT 7 ETM+ DATA FOR COASTAL HABITAT ASSESSMENT IN SUPPORT OF FISHERIES MANAGEMENT

摘要

Coastal habitats such as coral reefs, mangroves, seagrasses, and algae are important to fisheries management since these serve as indicators of fish stock, the health status of the coastal environment, and others. The suitability of Landsat 7 ETM+ data for mapping these coastal habitats was evaluated by the study. The study areas are two bays located in the province of Palawan in the Philippines, namely Puerto Princesa Bay and Honda Bay. Although adjacent to one another, the two bays actually represent different environmental conditions. Typical algorithms for the correction for the effects of water depth, radiometry, the atmosphere, and scene orientation were applied to the image. The resulting satellite image map was evaluated for visual interpretability of the coastal habitats under consideration. The appearance of these habitats, as well as that of some coastal landforms, in selected combinations of Landsat 7 ETM+ bands, is shown in the paper. Limitations in the level of habitat classification that are possible with Landsat 7 ETM+ data are also enumerated. The preprocessed satellite image was also subjected to digital classification techniques using field and other data gathered during site visits conducted in November 2000 and April 2001. Results of the classification are also discussed in the paper.