Multitemporal Analysis of Geoenvironmental Elements of the Coastal Dynamics of the Region of the Ponta do Tubarão, City of Macau/RN, on the Basis of Remote Sensing Products and Integration in GIS

The study area is inserted on the region of Macau in the northern coast of the Rio Grande do Norte State, composed of tertiary and quaternary sediments. This region is characterized by the intense action of coastal processes, causing the morphologic instability in the area beyond the interference of human activities, petroliferous industry, salt companies and the expansion of shrimp farms. This situation justifies the integration of scientific multidisciplinary and multitemporal studies to the evaluation of the changing behavior of this coastal environment. This study of environmental characterization is a basic tool to the identification of areas for protection and recovery, mainly those that suffer huge social-economic intervention. The main goal of this paper is the geoenvironmental monitoring by the analysis of multitemporal images (from years 1989, 2000 and 2001) of georeferencing orbital sensors, from the topographic maps (SUDENE SB-24-X-D-II Macau and SB-24-X-D-III São Bento do Norte, both with 1:100.000 scale) and photos from low altitude aerial surveys. These sensors products had been analyzed by through digital image processing techniques to produce index maps (land use, geology, geomorphology and soil) and environmental vulnerability to the social-economic occupation, aiming to determine sensitive and/or damaged areas. The thematic maps had been produced on 1:50.000 scale and stored in georeferencing database composed in a GIS, being used as source of consultations in a decision making to the environmental sustainable of the region and on Oil-Spill Environmental Sensitivity Maps of the Coast Areas. The application of these techniques in the area allowed the optimization and/or implantation of social-economic activities causing low environmental impact, avoiding environmental protected areas and benefiting the investors with better productivity and security in areas selection.