The New Epistemic and Theoretical Rationality Governing the Spatial Organization of Urban Systems

By reviewing the literature of spatial organization and analyzing urban systems as an interdisciplinary field, two different paradigms have been recognized: size-based and network-based paradigms. The first one relies on the definition of urban system as a collection of nodes (urban settlements) organized based on their internal attributes. This paradigm, while ignoring interaction among them, focuses on the concentration of activities or functions in nodes. In the last few decades and with the emergence of the system approach, defined as “an interdependent national or regional set of cities” as a system, considerable attention has been paid to investigating reciprocal interurban relationships. In this period, the element of interaction became more important in the description of urban systems. Following this, since the position of a given city in the urban system is a function of interurban flows, it is affected by the relationship with others. This approach considers the interurban relationship as horizontal and non-local interactions, which are features of service economies versus industrial economies. Thus, to understand and apply these approaches, first, the theoretical literature on space organization in urban systems and its evolution were reviewed; then, the new dominant theoretical and epistemological rationality, with its attributes and components, was explained, compared and categorized in order to develop new insights for operational research. This article is fundamental in its objective, and has employed descriptive methodology based on contextual data to do a comparative study of theoretical content and ontological basics of traditional approaches versus new ones

Exploring an integrated spatially model for land-use scenarios simulation in a metropolitan region

Spatial simulation of land-use change scenarios in metropolitan areas is essential for analyzing both the causes and consequences of various future scenarios and is also valuable for land-use planning and management. However, current simulation models primarily focus on spatial and rarely on quantitative driving factors. This article aims to simulate future scenarios of land-use changes in the Tehran metropolitan region (TMR) by combining different models to fill this gap. Thus, in the first step, land-use changes were analyzed in the period 1985, 2000, and 2015. Then, by identifying the impact of driving factors and land-use transition potentials with Logistic regression (LR), land-use changes were allocated using the Cellular Automata (CA) method. Finally, with the validation of the model, four scenarios of the current trend(CT), socioeconomic growth(SEG), ecological-oriented(EO), and integrated development(ID) were suggested with the combination of the System Dynamic (SD) model. The results show that the trend of land-use changes in TMR has led to the destruction of grassland, agricultural, and uncultivated lands and the continuation of this trend will increase the damage of built-up areas on valuable natural and ecological resources. In this way, proximity to roads, distance from built-up areas, and natural factors had the greatest impact on changes. Based on future scenarios in 2030, the change in the SEG-scenario shows a rapid increase in built-up areas (2858km and encroachment on agricultural lands (2171km . In the EO-scenario, destruction of grassland and agricultural lands and the growth of built-up areas will be limited, while CT-scenario leads to the high growth of built-up areas along with destructive impacts on natural and open spaces. In the ID-scenario, the built-up areas and grasslands will increase to 2808km and 7438km , respectively. Accordingly, policy-makers can use simulation of different scenarios to mitigate probable consequences of land-use changes in the metropolitan regions. 2) 2) 2