Sensibilidade Ambiental a Derramamento de Óleo e Mapeamento de Unidades de Paisagem na Região Portuária do Maranhão

Abstract

Several cases of oil spills in the world have encouraged the agencies and entities to improve methods, both preventive and corrective. In order to minimize the damage generated by the potential environmental impact, the environmental sensitivity mapping must be performed. Thus, the objective of this work is to apply the Environmental Sensitivity Index (ESI), from the mapping of the landscape units. The landscape units (17 in total) were identifed by visual interpretation of Ikonos high-resolution images, feldwork and a Geographic Information System. Subsequently, the ESI was applied, numerically represented by 1 to 10, on an operational scale. The corresponding study area is the port region of Itaqui on the island of São Luís, Maranhão, where there is an intense port trafc and an imminent threat of oil spills. The results point to the presence of high to low environmental sensitivity indices in the following environments: mangroves (ISA 10D), low banks and tidal flats (ISA 9A), sheltered scarps in bedrock (Paleo-clifl) (ISA 8A), exposed sand tidal flats (ISA 7), scarps and steep slopes in sand (ISA 3B), fne to medium grained sand beaches (ISA 3A), exposed rocky clifls with boulder talus base (ISA 1C), exposed, solid man-made structures (ISA 1B).