عنوان مقاله [English]
Optimal establishment is one of the basic issues in studying industrial towns around metropolitan areas. This optimization helps accessability to markets and manpower in an easy and cost effective manner. Spatial disperssion of industrial towns based on adaptability indexes is an essential factor. Balanced distribution of industrial towns should be analyzed by physical models.In this article the authors has tried to use strategic location of Tabriz in Azarbaijan Province, northwest of Iran, as the basis for studying industrial towns surounding this metropolis. A primary study resulted in selecting six industrial towns (Salimi, Saeid Abad, Rajaei, Fanavari Khodro, S.G. Khareji, Sahand) as case studies. Based on their location and using combined models of Fuzzy and Boolean, spaial dimensions and indexes for each town was determined. This helped analyzing their optimal and favourable placement. In fact, the main goal of this research is recognition and systematic classification of small towns sorounding Tabriz Metropolis in order to create spatial balance in the area. Understanding geographical location of these towns and their spatial distribution is the second goal of the research.
2- Theoretical bases
An industrian town is defined as: a place with specified limits and area where its location is selected according to laws and regulations of industrial projects site selection based on national industrial towns development strategy and where required infrastructures and services are provided in accordance with activity. An industrial town is a prepared land divided into smaller parcels for the establishment of different industries and will be available to investors with permits based on legal regulations. In the assessment of global challenges of industrial locations, issues like standard distance and performance are frequently discussed. In different countries industries are classified in a way that they are established in different areas in a harmoneous manner. Another important subject highly considered is employment generation for people who reside in or around projected site, specially rural residents. At present agriculture is unable to create employment for all villagers and industrial towns can enhance opportunities. Of course, this requires planners to be familiar with new production technologies and economic management.
The Boolean Logic is based on weighing elements between 0 to 1, in which exact boundry between ideal and heterogeneous points are defined. Considering communication lines in the studied area, all selected industrial towns receive high value, or 1. This, in most cases, is related to their location along Tehran â Tabriz transport routes. The northern Tabriz fault runs along this route and except 2 towns (Salimi and Rajaei) others are built on or near the fault, threatened by earthquakes. Hight classifiation of Boolean Logic indicates that S.G.Khareji town has better standardized location than others because its establishment in Urumieh Lake basin in Sufian â Shabastar region. The slope map of the area indicates that lands around Tabriz towards Oskoo, where Rajaei and Sahand are built, has more heterogeneous slope than others. On the other side, Saeid Abad, near Bostan Abad, provides best lands for the establishment of industrial towns. Studying all six towns from the view point of their location within influence zones of major cities, the northeast-southwest corridor of Tabriz â Oskoo â Azarshar provides the best place for indusrial towns. The low influence degree of Sufian on S.G.Khareji town and long distance of Saeid Abad from two cities of Bostan Abad and Tabriz, result in 0 points for these towns.The Fuzzy Logic indicates that land performance increases from southern Tabriz highlands towards Sufian, Marand and Shabastar. This is a reliable indicator for optimization of sites for the establishment of industrial towns. It should also be noted that except S.G.Khareji town, other sites are greatly affected by availablity of water. The fuzzy also indicates that all towns are heavily influenced by Tabriz metropolis and Azarshar city.
Studies indicate that Boolean method, though very simple and easily analyzable on data layers, it has some disadvantages. The most important of these is that it is not spectral as Fuzzy Logic. Another point is that one should always consider that selecting criteria and number of locations is important for any decision making. Factors like wind direction, geology, soil, etc., might have different effects on analytical results. In general, this research shows that increasing distance from Tabriz metropolis decreases desirablity of sites selected for industrial towns and increases limitations.
On suggested map, the optimal points for the establishment of industrial towns are shown based on Fuzzy Logic analysis. The most optimal point is from Rajaei to Salimi towns, the region between Oskoo, Khosro Shahr, Sardrood and Esfanjan, based on geological structure, transportation network, distance from earthquake faults and proximity to Tabriz metropolis. Next optimal point would be the southern part of Sufian due to its distance from geologic faults. Iranagh, south of Saeid Abad, for the same reason, can be a desirable place for the establishment of new industrial towns.