Influencing Variables on Urban Spatial Structure in Metropolitan Regions; a Study in the Contemporary Theoretical Approaches and Practices

Abstract: metropolitan regions as a result of the steady stream of urbanization in industrial periodwhich have occurred during 20th century, become the engine of countries growth and development.in the process of formation and development in these areas, spatial structuring that define through twoelements of population and activity with the communication structure interacting between them, has beeneffective on the overall performance and the characteristics of spatial structure in metropolitan regions.the main goal of this research is to study the most important factors influencing the trends in the spatialstructure of metropolitan regions. through studying the various theories and also the contemplation ofmetropolitan region samples in developed and developing countries, it is hoped that a better and deeperunderstanding of total trends of spatial changing will be reached. besides the main reasons influencingthese trends can be identified. the research method is comparative-analytical, and the study is done by thehelp of recent literature analysis and review on the spatial structure of metropolitan regions. results showthat in a general, metropolitan regions in developing countries have similar trends in their structure, butwith time delay more than developed western examples. moreover the four major factors: communicationinfrastructure, economic globalization, decentralization and more effective communication betweenagencies and companies have had the most influence on the spatial processes and changes.