Evaluation for Characteristics of Flood Plain in Urban Area by Geographic Information on Space and Time

利用地形图、航片和地理信息系统中的卫星数据，研究了日本城市河流三条河、大分河、大鱼岛河和志拉河泛滥平原的地形条件及其变化。考虑了过去发生自然灾害地区的地面条件。结果表明，在利用这些地理信息对滨河地区进行分析时，可以从滨河地区地表条件的分布及其变化特征来定性和定量地评价城市地区的自然灾害。证实了地理信息系统分析过程不仅适用于泛滥平原，也适用于滨海平原和国外泛滥平原。

In this study, ground conditions and their changes of flood plain of Japanese urban rivers such as the Mikasa River, the Ooita River, the Ooyodo River and the Shira River were investigated by using topographic maps, aerial photographs and satellite data in GIS. The ground conditions at the area where the natural disaster occurred in the past were considered. As a result, in the analysis using such geographic information for the flood plain, it was clarified that we can evaluate the natural disaster at the urban area qualitatively and quantitatively from the characteristics on the distribution and its change of the ground condition in the riverside area. We confirmed that the GIS analysis process is applicable to not only flood plain but also coastal plain and foreign flood plain.