Abstract
The proper delimitation of planning regions is a critical issue in the success of regional plans, and it constitutes a rich domain of research. In this paper, it is argued that planning regions should be based on functional regions– if the main intention is to increase the driving power of the people behind the planning process. Within this context, the aims of this paper are twofold: (1) to develop an algorithm (FRGIS) for the delimitation of planning regions on the bases of functional regions, and to implement it by using the scripting facilities available in Free and Open Source Software for Geographic Information Systems (GIS); and (2) to delimit the planning regions in Turkey by using FRGIS and the script developed for this purpose, by employing the commuting flows occurring between districts in the case country (Turkey) in 2010. The results show that FRGIS is successful in terms of the formation of spatially-balanced regions having higher levels of self-containment compared to those of existing regions. Nevertheless, it is also evident from this study that a combination of the nomothetic and ideographic methods of science is inevitable if functional regions are to be employed as planning regions.