عنوان مقاله [English]
City cluster development is an urban-led approach that was proposed for achieving sustainable economic and social development in the regions. This approach utilizes eight key factors for identifying homogeneous urban centers for providing a joint development plan in the regions. The purpose of this research is to review the conceptual model and indicators that affect on and examine it in a part of Tehran province. According to the survey, the emergence of urban clusters is related to the urban field concept, but the effective indicators on this concept differ in periods of time and conditions of the regions, so the urban field analysis done by using content analysis method in 5 patterns and its relation with the above key factors. The results of the analysis show that four cases can be identified in homogeneous clusters and the rest can be presented in the proposed scheme.
Today, regions face major challenges in various fields, so planning for them is important and inevitable. CCD is a process of economic and social development which built-up a number of human settlements that linked together. CCD responds to the new patterns of urban growth, which are shifting from mono-centric to polycentric. Experiences show that at least eight key factors need to be assessed to determine whether or not to use CCD as an instrument for urban-led, inclusive economic and social development:
- institutional and governance mechanisms;
- demographic, resources, and spatial
- factors; development planning coordination over
- time and jurisdictions; use of land resources and land tenure;
- economic growth potential and trade functions;
- taxation, intergovernmental transfers, and fiscal discipline;
- infrastructure and information networks; and
- role of private sector participation
Many of the key factors mentioned are closely related. Therefore, efforts to achieve economic and social development through the CCD require a full understanding of various economic, social, institutional and technological resources. Therefore, the present study investigates the history of urban clusters and its relation with regional development.
In urban and regional planning, the emergence of city clusters is linked to the concept of an “urban field,” which is composed of the economic and social influences emanating from a particular city. The present study, considering the concept of urban field in different period times, investigates the dimensions and effective components of its recognition in five patterns. According to the study, four factors of the main approach will be considered in identifying urban clusters and the rest in planning time.
An analysis of this approach is carried out at two levels:
1. The regional dimension includes the desired Districts. This section identifies which cities can be located in each cluster in terms of performance and activity.
2. The local dimension that includes the cities located in each cluster and their characteristics in four dimensions (demographic, social, economic and physical).
To analyze the alternatives of this research, Cluster Analysis approach has been used at the regional level and the PROMETHEE technique in local level.
3. Results and discussion
The analysis result shows that the two main groups are within the scope of the study. The cluster number one consists of Shahriar, Malard and Rabat-Karim Districts. According to the survey, the cities of this area have a good elevation, slope and climate, but only Baghestan and Ferdosiye have a suitable soil for agricultural activities. Although there are some agricultural activities in some of these cluster cities like Shahriar and Malard. Furthermore, substantial industry activity is in of some cluster cities (like Mallard). So the proper activity for this area is agriculture and industry
Cluster number 2 consist Islamshahr, Qods and Baharestan Districts, which have a geographical distance from each other. This cluster includes Islamshahr, Chahardangeh, and other cities. The cities of this cluster have a good elevation, slope and climate, but they have no fertile soil. Therefore, the proper activity for this area is industry and services.
The second matrix is based on the cities located in each cluster and their ranked with using Visual PROMHETEE software. This ranking takes into account two other important factors in regional planning, human and space. Human, account by studying demographic factors such as population density, level of literacy and …, space by natural characteristics and the percentage of urban services and infrastructures allocated area
The results of the ranking indicate that Shahriar has the highest rank among the cluster cities. Mallard and Rabat Karim, which rank 2 and 3, are in competition with the central city. Ranking of the second cluster shows that Chahar-Dange, Ghods and Islamshahr cities ranked one to three. Thus, the central city of this cluster is Chahar-Dange and Quds and Islam Shahr compete with the main city.
In this approach (city cluster development), regional development create through interconnected or separate urban areas, and what the link urban centers in the form of urban clusters is Related economic and potential activities (from a natural and artistic perspective). If the areas concerned are similar or homogeneous in terms of dimensions and indicators studied, planning for them will have done in the form of a joint development plan. The city centers in the study areas may already have been linked to by a network of infrastructures or not.
The present study examined this issue in part of Tehran province. Tehran province, as one of the most densely populated provinces of the country due to the establishment of the capital (Tehran city), has undergone many changes.
The most important of these changes are, the abstraction of Karaj and its subordinate cities, the emergence of Pardis, Ghods, Baharestan, and …, into independent districts, the formation of new urban centers that create from rural areas and new cities.
Therefore, by using the city cluster development approach with considering porter diamond model and effective factors in determining urban-fields, the administrative-political divisions in the part of Tehran province were analyzed and evaluated.
The results of the analysis show that the studied areas have a coordinate activity and divide them in to separate area, cannot lead to coordinated development in them.