The Establishment of a Dynamic Simulation on the Impucts of Oil Split Accidents on Coastal Ecosystem

船舶碰撞、搁浅、油轮装卸困难等油液分离事故造成的油液污染，除了给当地社会带来社会经济问题外，还容易造成生态系统的破坏。特别是，根据石油污染的程度，对生态系统的严重影响有长期延续的趋势，这取决于采取适当的措施来防止扩散和收集分离的石油。因此，应采取措施科普石油污染对海岸带生态系统的影响。为此，采用系统动力学的方法，以浮游植物、浮游动物、游泳动物、碎屑物和溶解氧为控制因子，建立了海洋石油污染与海岸生态系统的分析模型。并对广岛湾围隔海域的海岸生态系统在不同溢油量、溢油种类、溢油事故发生季节、溢油收集量等条件下进行了数值模拟。从计算结果可以较好地把握石油污染对海岸带生态系统的影响。

Oil pollution by the oil split accident, such as ship collision, running aground and awkward cargo handling of oil tanker, may apt to cause the damage of the ecological system, in addition to get the local community into socio-economic trouble. Especially, the serious effect upon ecosystem has a tendency to extend over a long period of time, according to the extent of oil pollution that depends on taking the suitable measures to prevent from spreading and to gather the split oil. Thus, the countermeasures should be taken to cope with the impact of oil pollution that is related to the influence on the coastal ecosystem. Accordingly, the relation between the degree of oil pollution and the coastal ecosystem has to be clarified by taking some appropriate step.For this purpose, an analytical model on the coastal ecosystem was established by using the way of System Dynamic in which phytoplankton, zooplankton, nekton, detritus and dissolved oxygen are assumed to be governing factors in this environmental problem. And a numerical simulation on coastal ecosystem in an enclosed area of Hiroshima bay was carried out in varying the quantity and kind of spilt oil, the season of outbreak of accident, the oil gathering quantity. From the calculated results, the impacts of oil pollution on coastal ecosystem can be grasped considerably.