Environmental Sensitivity Index Mapping for Oil Spill using GIS Approach, Case Study from Bashayer Oil Terminal, Sudan

— The Environmental Sensitivity Index (ESI) has become a benchmark for coastal managers, planners, and scientists in determining the effects of oil spill on coastal habitats. The Sudanese Red Sea Coast is highly important for the country exports and imports. It is characterized by rich environment of mangrove, fishes and coral reefs. This study aimed to produce ESI of Red Sea Coast to oil spill during the period from December 2007 to January 2008 using geospatial techniques with considering of Bashayer II Crude Oil Export Terminal. The data used include digital elevation model, LandSat scene and coraf reef distribution in the coast, slope of the area and the distance from marine terminal (MT).Various image processing techniques were conducted including true color composite (bands 2/3/4), clipping the study area, on-screen digitization and shapefile conversion of land use/land cover classes and buffering tool to categorize the distance from MT. Wind direction data was used to identify the imminent effects of wind on the coral reef. Then a model was formed to rank the different coral segments to oil spill. The result showed that six segments ranged from the most sensitive to the least sensitive; three segments were far from MT, two were close and one was very far. Moreover, the study ranks reef segments sensitivity following the wind direction. Closed reef segment to MT and moderately sheltered (ESI-6) were the most highly sensitive category, followed by next five ESI ranks; whereas very far reef segment from MT (ESI-1) with moderately sheltered characteristic was ranked as the least sensitive. The study has demonstrated the effectiveness of GIS in monitoring and modeling oil spill in the area. The study recommended preparation of ESI maps by consulting multidisciplinary scientists to monitor oil spill.