Multispectral Change Vector Analysis for Monitoring Coastal Marine Environments

Abstract

Documenting temporal changes to coastal zones is an essen­tial part of understanding and managing these environ­ments. The exclusive use of traditional surveying tools may not be practical for monitoring large, remote, or rapidly changing areas. This paper investigates the utility of multispectral Landsat Thematic Mapper satellite data for docu­menting changes to a Caribbean coastal zone using the change vector analysis processing technique. The area of study was the coastal region near the village of Buen Hombre on the north coast of the Dominican Republic. The primary habitats of interest were the intertidal mangrove for­ ests, and the shallow water seagrasses, macroalgae, and coral reefs. The change vector analysis technique uses any number of spectral bands from multidate satellite data to produce change images that yield information about both the magnitude and direction of differences in pixel values (which are proportional to radiance). The final products were created by appending color-coded change pixels onto a black-and-white base map. The advantages and limitations of the technique for coastal inventories are discussed.