Oil Spill Risk Identification And Zonation At Sea Based On Remote Sensing And GIS

With the rapid development of ocean exploitation and marine economy,oil spills in the ocean is increasingly worse.In recent years,serious oil spill accidents happened frequently.For a better understanding of oil spill characteristics,identification and zonation of oil spill risk at sea is becoming an important part of oil spill risk management.However,limited research on this subject restricts effective technical support for oil spill risk management.The rapid development of satellite remote sensing and Geographic Information System(GIS)provides new methods for marine oil spill risk zonation.In this study,we apply natural disaster risk theory to oil spill risk identification and management,develop a new oil spill risk identification and zonation method based on remote sensing and GIS,and build up the framework of marine oil spill risk system,which includes three components.(1)Based on satellite remote sensing technology,a rapid identification and extraction method for two major oil spill sources(ships and off-shore platforms)were proposed.An oil spill source intensity assessment model was then studied.The results showed that the proposed algorithm can effectively remove ship azimuth ambiguities on Radarsat-2 images and further improve the accuracy of ship detection on SAR images.Meanwhile,off-shore platforms could be extracted by change detection method of multi-temporal SAR images.With oil spill source intensity assessment model,the contribution of different risk sources could be calculated,and the map of marine oil spill risk source intensity zoning could be created.(2)Utilizing remote sensing images with medium/high spatial resolution,such as GF-1 and GF-2,mariculture area with shorter variation period could be quickly and accurately identified.Then,other oil spill sensitive resources data were collected and managed in a geodatabase.The spatial distribution of these oil spill sensitive resources was mapped.After that,the oil spill sensitivity index of various sensitive resources was evaluated by expert scoring method.Marine oil spill risk damage zoning map was compiled by combining oil spill risk source intensity index and oil spill sensitivity index.The map could reflect the risk level of different zones potentially affected by oil spills.(3)Firstly,15 major ports around the study area were chosen for oil spill emergency capacity assessment.Secondly,oil spill emergency capacity index evaluation system,including clean-up capacity of shoreline,clean-up capacity at sea,and recycling and disposal capacity on land,was established with fuzzy comprehensive evaluation method.Then,from the perspective of the whole oil spill risk system,considering the three aspects of risk source,oil spill sensitive index and oil spill emergency capability index,we use the scenario simulation method and GIS spatial analysis technology to carry out oil spill risk zonation process.The oil spill risk management zoning map is used to describe risk degree of the whole area.This study aims to provide an effective tool for marine oil spill risk prevention and management.In this research,an oil spill risk identification and zonation method based on remote sensing and GIS was proposed,and a case analysis in the Bohai Sea was performed.This method could effectively identify and extract the relevant oil spill risk information.On the basis of marine oil spill risk system,three levels of risk zoning map were initially compiled,including marine oil spill risk source intensity zoning map,marine oil spill risk damage zoning map,and marine oil spill risk management zoning map.Using these maps,we can reveal the spatial distribution characteristics of oil spill risk,determine the priority management order,carry out effective oil spill emergency response,and improve the initiative and scientific level of marine oil spill risk management.