The Use of Central Place Theory and Gravity-flow Analysis to Delineate Economic Areas

A growing awareness of the need for a comprehenThe first written exposition of central place theory sive approach to regional and local planning for dates from the publication in 1933 of Walter studying urban and rural areas as parts of an interrelaChristaller's Die Zentralen Orte in Suddeutschland.1 ted socio-economic system has stimulated interest in Briefly, Christaller noted that the spatial organization the problem of delineating economic regions, areas, of economic activities was ordered around a hierarchy and sub-areas. The Office of Business Economics, U. of urban places. At the top of the hierarchy are the S. Department of Commerce, has designated 173 cities which serve as the central place for a broad economic sub-areas in the U. S. for purposes of planhinterland relative to very specialized services (such as ning by federal agencies. State governments are also higher education, regional government, the arts, etc.). busy delineating planning areas for state and local At the bottom of the hierarchy are the hamlets and agencies. Ten such planning areas were designated in villages, which serve as the central place for a someSouth Carolina by executive order of the Governor in what smaller hinterland relative to such everyday March 1969. Presumably, future public policies and activities as food purchasing and local government. In programs in such fields as natural resource managethe middle strata are wholesale centers, area shopping ment, industrial development, housing, and highway centers, etc., which serve intermediate-sized hinterconstruction, etc., will be designed and implemented lands[l, p. 107]. on the basis of these spatial delineations. The role of the central place as the economic cenAlthough economic geography has made major ter of some spatial expanse may be demonstrated by strides in recent years toward the development of observing traffic flows as manifested in shopping analytical tools for the study of spatial economic patterns, distribution systems or the journey-to-work phenomena, there is no definitive system for delineof commuters. Ideally, all three measures should be ating economic areas. However, there are two basic used together, but data limitations often intervene to concepts upon which such delineation may be postuforce a more restricted observation. In such cases, lated: (1) the "homogeneity concept," which views commuter patterns appear to be a useable index of an area as being composed of spatial units which are the attraction of a central place over some hinterland. of similar economic structure and character; (2) the A particular pattern of commuting is built up because development pole, or nodal development theory, of the local geographic distribution of jobs [5, p. which views an area as the hinterland of some central 125]. The number of jobs in any one location is place [7, pp. 709-727]. Actually, areas defined on proportional to the number of economic functions the basis of the development pole or nodal concept performed at that site. The larger the central place, may be homogeneous to the extent that the residents the greater the number of functions it performs, the of the surrounding hinterland interact in the same greater the employment requirements of each funccentral place [2, p. 366]. Our objective is to employ tion, and the wider the hinterland over which it a synthesis of the two concepts using tools developed attracts workers to man its economic activities. It by economic geographers and traffic planners for follows, therefore, that there is also a hierarchy of other purposes. hinterlands (regions, areas, sub-areas) which corre-