関東地方における旧軍用飛行場跡地の土地利用変化 Changing Land Use of the Former Military Airfields in the Kanto District
Military establishments are special kinds of public facilities which are not oriented to common users and are under direct government control. To verify their strong spatial influence, the author reviewed a series of policies on the disposal of national properties, and studied changing land use of the former military airfields in the Kanto District.<BR>With the end of World War II, a large number of military establishments and properties all over Japan lost their functions. Many of them were released for public use and others were taken over by U.S. military. Their disposal was affected by three groups of government policies : fundamental laws on the disposal of national property exercised by the Finance Ministry; several policies on postwar reconstruction, industrial promotion, regional development, etc. ; and the occupation policies with military purposes and defense policies based on the Security Treaty between Japan and U.S.A.<BR>Based on the investigations covering 60 airfields in the Kanto District, the author has found that three stages characterize the major patterns of land use conversion.<BR>In the first stage (1945-1960), most of the former Japanese military airfields became farmlands for food supply and unemployment relief under the reclamation policy. The other airfields, especially those located closer to the metropolis, remained for military use by the U.S. Armed Forces.<BR>The second stage (1960-1975) corresponds with the period of rapid economic development, and a lot of industrial estates were developed on the former airfields. Most of them were converted from reclaimed farmlands. Another conspicuous land use emerging on the former airfields in this period was military use by the Japanese Self Defense Forces, taking over the U.S. military bases or reclaimed farmland.<BR>The third stage (1975-) is characterized by large-scale redevelopment for public purposes on the former U.S. military airfields which were returned to the Japanese Government.<BR>Although these three stages generally correspond with the Japanese socio-economic changes throughout the postwar period, some of the land use changes preceded general changes, because they were authorized by the government policies.<BR>Actual cases of the changing of land use on the 60 airfields are classified into five types : A (farmlands), B (farmlands to industrial sites), C (U.S. military to public use), D (U.S.military or Japanese Self Defense Forces), and E (farmlands or U.S. military to airfields). The average distance from the metropolis is the greatest in type A, followed by B and D. C and E are situated closest to the metropolis. Type C has had the most extensive and various spatial effects on surrounding areas. It is also worth noting that the boundaries of former military airfields can be easily identified in many cases even after land use conversion.<BR>These changes have influenced various aspects of the changing spatial structure in the Kanto District, mainly because of the land property characteristics (large-scale area, firm ground surface, land ownership with grid pattern, etc.) and historical factors (former national lands with special public facilities).