Review and Prospects on the Study of Traffic Flows in Geography

Abstract

Since 1960's, a new philosophy in geography was developed around two interdependent foci; the spatial science and the study of systems. The objects of transportation geography consist of inventory, network, flow and modal systems of transportation, and transportation geography aims to clarify the pattern of their spatial structure through their spatial connections and interaction. Therefore, transportation geography is one of the most systematic fields in modern geography, and it should be understood in terms of relationships between many elements in a whole system.
The passenger and freight flows are the important spatial flows in socio-economic system. The regional interrelation in the flows of passengers and freights involves all human behaviors that help to create socio-economic system, and this relation is required to maintain spatial organization and stimulates the development of the system. Accordingly, in transportation geography the study of passenger and freight flows is important to clarify the regional relationships.
In the review and prospects on the traffic flows in the past, the passenger flows were not treated with, and only freight flows were studied by some geographers. The purpose of this paper is to present the problems and prospects of the study of traffic flows. The author attempts to deal with the study of passenger flows in the items of aggregation and disaggregation based on data characteristics of the flows, and the study of freight flows is divided into three aspects of volume of shipments, efficiency of flows and structure of flows according to Smith (1970).
Major prospects and problems are as follows:
(1) The consideration to the scale of study area is a basic problem in the study of traffic flows, and standardization of size of traffic zones to be set is also important. And the definition of level of resolution (international transport, regional transport and local transport) as geographic scale is a major problem as pointed out by Hay (1981).
(2) New kinds of flow data are needed in the traffic flows study. In some cases, there is a limitation in the conclusions derived from an analysis of interregional freight flows in terms of physical volumes (ton). However, if necessary, the data on the physical volumes of flows should be transformed into the estimated monetary value or the other forms. In addition, with regard to production, consumption, foreign trade and economic growth processes, the data should be broken down by region. An important problem in the analysis of passenger flows is the identification of a suitable basis for classifying the trip purpose, the occupation and socio-economic status of the travellers. The data on trip purpose and occupation or socio-economic status are in need on the regional or national scale.
(3) In the study of traffic flows, dynamic (time serial) analysis is indispensable to clarify the spatial reorganization in the process of the socio-economic development and improvement of transportation facilities.
(4) In disaggregated analysis of passenger flows, the modal approach is of significance, because the aspects of passenger flows are different individually in terms of travel time, cost, convenience of facilities and the behavior of traveller and his purpose. Additionally, the socio-economic development and the improvement of transportation facilities act to diversify the passenger flows.
(5) The freight flows should be analysed to clarify the regional structure of origin and destination of traffic, as pointed out by Hay (1979), as well as the pattern of flows and the special characters of regions. In other words, flow pattern can be explained in terms of regional character under the consideration of the positive and negative factors of supply and demand, and the analysis of flows as a link between origin and destination is efficient to explain the traffic distribution and regional relationship.
(6) In transportation geography, the traff