過疎高齢島嶼地域における減災計画のための地域分析方法

抄録

A detached island in Okinawa Prefecture is roughly typified as an island that is a tourist resort or not tourist resort. Both types of islands have important problems. The resort islands have problems such as drought, waste disposal and succession of tradition. On the other hand, aging and a decrease in the population are progressing in islands that are not resorts. This study focused on the Tonaki Village, a small island that is not a resort.
The Tonaki Island has a population of 440 with an elderly ratio of approximately 40%. According to the Okinawa tsunami and high tide assessment damage report, if an earthquake occurs off the Kume Island north of Tonaki a tsunami is predicted to arrive at this island in 16 minutes. Furthermore, the entire community will be flooded by high tide.
The purpose of this study was to develop a planning system for disaster risk mitigation suitable for this region. In this paper, I clarify problems with the structure of the social network that pays attention to vulnerable persons at the time of a disaster using information from resident's daily life activities and associations with neighbors.
The following experiments were carried out. First, a field survey was conducted to clarify the disaster weak factors. Although a historic preservation district is the pride of the residents, but it is also a factor vulnerable to the disaster. Second, refuge actions after a tsunami were simulated. This simulation was analyzed for four cases: case 1, each person taking refuge in designated evacuation spaces; case 2, a school and a welfare center added as evacuation spaces to case 1; case 3, when one support person helps a vulnerable person at the time of a disaster in addition to case 2; case 4, when two support persons help a vulnerable person in addition to case 2. Even if the safest situation represented by case 4 is assumed, the results of the simulation shows the time for reaching a refuge is only 3 minutes and 48 seconds. Finally, an analysis of the relationships between residents clearly showed that support persons do not recognize vulnerable persons. Many of the support persons are teachers. Most teachers in the detached island are precious young persons essential for risk management. Therefore, the relationships between young teachers and vulnerable persons need to be developed in daily life.

JEL Classification: Q54