Abstract
The spreads of urban districts have been eroding many kinds of land uses in and around the cities. For the conservation of open space, it is important to know the expanding directions of urban districts, which are mainly caused by the concentration of population. The purpose of this study is to clarify the change of land uses in proportion to the spread of "Densely Inhabited District (DID) ", for making a guideline of conserving open space. The distribution patterns of DID within a 50 km radius of Tokyo Metropolitan Area were compared during the period from 1960 to 1975. Over 70% of the newly spread DID areas appeared in the areas adjacent to the existing DID. There is a close interrelationship between the spread of DID and that of urban district in the northeastern area of Kanto district. On the basis of the distribution of open space in and around DID in Saitama prefecture, the author proposed four "Conservation Zones" of open space-central DID zone, marginal DID zone, fringe zone and remote zone. The conservation guideline of open space is discussed for each of four zones. (*DID is defined as an area within a local body that is composed of a group of contiguous enumeration districts, each of which has a population density of about 4, 000 or more inhabitants per square kilometer, and whose total population exceeds 5, 000 at the date of survey.)
