Application Of Oil Spill Modeling To Natural Resource Damage Assessment In Bohai Sea

Oil spills not only cause large-scale seawater pollution,but also pose a serious damage to the ecosystem,which will lead to the loss of the ecological resources of the sea area.To this end,using appropriate methods to assess the ecological risk of oil spills and calculate the natural resource losses caused by accidents is of great significance for post-disaster response and ecological restoration.This paper takes the Penglai 19-3 oil spill incident in Bohai Sea as an example,to study the ecological risk assessment(ERA)and the natural resource damage assessment(NRDA)of the accident.Firstly,two oil spill models(GNOME and ADIOS)simulate the trajectory movement and weathering process of oil film at the beginning of the accident.The results show that the oil film diffuses to the northwest coastline at an average rate of about 500km~2/day.The density,viscosity,emulsifying water content and evaporation rate are also increased.The airborne benzene concentration reaches 0.1ppm.Base on the simulation results,the main dominant species in the Bohai Sea area were used as experimental objects,and 24,48 and 96 hours were used as the exposure duration.Three sets of species sensitivity distribution(SSD)curves were fitted to the oil spill accident for the ecological risk assessment.According to Henry's law,the concentration of the main toxic substances(benzene series)in the polluted seawater has reached 1300?g/L,and the ecological effect risk on the Bohai Sea species increased at 1%/day.This concentration almost reached the 5%species Hazard Concentration 5%(HC5)at the 96-hour exposure duration.In the comprehensive simulation experiment,the increase of the coverage area of the oil spill and the increase of the ecological effect can be seen that the ecological effect risk of the accident on the Bohai Sea area has a quadratic function growth trend in the short term.Meanwhile,the Bohai Sea Natural Resource Damage Assessment(NRDA)system has divided into two parts:physical impact assessment and ecological impact assessment,and used Resource Equivalency Analysis(REA)and Habitat Equivalence Analysis(HEA)to calculat the two aspects of the oil spill accident.The results show that the direct loss of resources caused by the accident is 4.1-6.8 million yuan/day,and the loss of ecological resources 1-4 days after the accident respectively.For:604,000 yuan,3,383,000 yuan,9,788,000 yuan and 21,267,000 yuan.