Most municipalities place railway stations as the core of their “Location Optimization Plan”. Those plans are for compactification urban and residential areas to around railway stations. However, as the porous phenomenon proves, urban shrinkage does not always occur from outer edges of the area. Furthermore, suburban areas have motorized society as one of its aspects. There are difficulties on carrying out the compactification and demographic aggregation around railway stations.
This thesis clarifies the possibility of compactification in the station area at suburbia. It is analyzed based on the trend of population increase and decrease in each subregion in the suburban area. To identify the suburban municipalities that strongly related to the urban central area, the Keihanshin-Employment District is stated. The district includes municipalities with more than 10 % of employees are commuting to the central urban area. To observe the situation of population aggregation around the suburban railway stations, the spatial autocorrelation method is used. The targeted areas for the method is subregions in the suburban area of Keihanshin-Employment District. The value for the calculation is Demographic Cohort Ratio of each generations. The generations are separated into 4 groups based on the life stages; 1) Young-Aged (20 to 34), 2) Middle-Aged (35 to 49), 3) Pre-Retired (50 to 64), 4) Early Elderlies (65 to 69).
Findings are under below;
1. The area of all generations without Y-A where population settlement and influx occur, decreases its aggregation tendency. Especially P-R and EE still settle on the outer edge of suburbia.
2. The increasement of population settlement and influx tendency within the station sphere occurs at younger generations. Even in the same station sphere, the population influx tendency is relatively stronger at subregions which is near by stations than the outer area of the sphere. On the other hand, the population settlement tendency is relatively stronger at subregions which is far away from stations than the inner area of the sphere.
3. Younger generations choose their residential areas at the place where directly accessible to the central urban station. On the other hand, elderlies mostly settle or flow in the areas around the branch railways.
4. Subregions where population settlement and influx occur relatively spread along the railway lines compared to 2005.
5. Y-A settle or inflow with facial continuity in the station sphere of stations that express trains stop. On the other hand, the same tendency of EE occurs as topically.
6. In the case of Y-A, population settlement and influx have been occurring at same express stations since 2005. On the other hand, the bipolarization of express stations either station with continuance of population settlement and inflow tendency or station that decreases the tendency, is observed at the case of M-A.
7. Even some part of suburban area such as southern part of Osaka prefecture, has relatively low tendency of population settlement and influx, there are few station spheres at the area that demographic cohort ratio is relatively high in all generations.
8. There are stations that population settlement and influx tendency is different in each generation, even if the stations are on the same railway line or close to each other.
9. The structure of railway station sphere is bipolarized into either the sphere with areally population settlement and influx tendency or the sphere the tendency occurs topically.
