Abstract
The housing development of hilly regions always accompanies the topographical trans-formation. The present study attempts to measure and explain the relationship between the progression of housing developments and the original surface of land in the northern hilly region of the Osaka plain by applying the “mesh” method to micro-topography. The results obtained are as follows:
1. The front of housing developments moved from farm land to forest regions. Senri Hill being the hub, it first proceeded from the outer fringes into the interior and then moved back again to the outer zones. As population increased, bus and railroad lines developed. Consequently, the time required to reach the nearest station decreased from twenty or thirty minutes to ten or fifteen minutes.
2. The main agents of housing developments gradually shifted from public corporations to private enterprises. Capital investment, machinery used, construction methods, and type of organization changed in the course of time in direct proportion to the ups and downs of economic conditions. Emphasis on housing supply shifted from quantity to quality. Underlying causes that compelled the compact and good quality housing led to high land prices, while topographically suitable construction sites were limited. And the stag-nation of purchasing power followed.
3. As Senri is the diluvial plateau lacking ground water resources, it had been left unused and remained sparsely populated until the 1960's and regarded as an empty and unproductive land, in spite of the fact that it was only fifteen kilometers to the center of Osaka City. Thus land prices were less expensive. This area was transformed into Senri New Town by an economically efficient cut-and-fill of soils, making use of the most of the complicated topography. As a result, the present land consists of many slopes, overpasses, and steep hills. As for community organization, the concept of the neighborhood-unit and disposition of housing contributed to the effective community development.
4. The transformation of the original terrain started in the areas characterized by the small relief features, low elevation, and low density of valleys. In terms of the direction of a slope, the intensity of housing development decreased in the land slanted toward the south where there was a good exposure to the sun and also in the land inclined toward the east, while it gradually increased in the shady slope with a northern exposure. The choice of land and the alteration of terrain advanced in the northwest and southwest sections where surface undulations were small, in the southeast where elevation was low, and in the south-west where there were fewer valleys.
5. The development of land that was formerly considered unsuitable for housing in terms of topographical conditions appeared at a later stage of the housing developments and could be seen in those areas adjacent to the already developed sections. The reason for this was that the high level of social conditions increased the pressure to develop further housing and resulted in quickening its pace, which in turn became the cause of developing the areas topographically unsuitable for housing.
