Marine Habitat Mapping Using High Spatial Resolution Multispectral Satellite Data

Abstract

Abstract The application of high spatial resolution and multi-sensor satellite was assessed to map the sensitive marine habitat of Tarut Bay in the western Arabian Gulf. The coastal zone of the Gulf is becoming more populated and industrialized with time, which requires an integrated monitoring approach to manage the valuable marine resources. In this study, Spectral Mixture Analysis (SMA) and a water depth removal model were applied to derive sea-bottom reflectance data. High spatial resolution Ikonos multispectral and panchromatic imagery are being integrated with SeaWiFS ocean coverage data to produce biotope maps for the project area. The image processing sequence includes linear spectral mixture analysis using the first four Ikonos bands, application of the water removal procedure, another stage of spectral mixture analysis, and then machine learning based feature extraction of marine ecosystem biotopes including coastal beaches, coastal vegetation, mud flats, rock flats, tidal channels, seagrass beds, subtidal sands, subtidal mud, and algal mats. Spectral Mixture Analysis models the recorded radiance from each pixel as a linear combination of endmember materials. The result is a set of fraction images that relate digital numbers to material abundance. Water attenuation coefficient k is being extracted from the SeaWiFS eight spectral bands for depth modeling over the study area. The goals of this study include: an assessment of the capability of high-resolution multispectral data and new remote sensing processing techniques for coastal monitoring, evaluation of the depth modeling algorithm for mitigating effects of the water column to map target features, development of a prototype geodatabase model for integrating diverse data about targets in a large enterprise database, and assessment of whether these techniques will lower the costs of expensive field data collection programs in the marine environment. Introduction The term biotope is defined here as a marine habitat that forms a recognizable entity based on the animals and plants that live within it (Basson et al., 1975). Our study area extends from Ras Tanura peninsula southward to the inlet bay north of Dawhat Zalum and includes a unique array of intertidal and subtidal biotopes (Figure 2). The northern portion includes Tarut Bay, which is a low-energy inlet bay and host to a fishing port, residential community, oil facility, and a major port. The coastal area south of Dammam to the Gulf of Salwah includes both exposed coastlines of relatively higher-energy and very shallow protected bays characterized by high salinity and extremely limited tidal circulation (Basson et al., 1975).