سازمان‌یابی فضایی و گسترش سکونتگاه‌های غیررسمی در کلان‌شهر تبریز

Introduction
Urban spatial structure and organization is originated from natural, social, cultural, political and economic forces. From past to now, these forces as important factor have played main role in city arrangements. Informal settlements organization and creation are also originated from current forces in city spatial arrangement. Industrial revolution with mass production and centralized form and urban communication facilitated development around environments. This resulted in creation of organization and new spatial structure based on quantitative form (city spatial development) and qualitative form (origination residence certain form). Urban population increase, industries development and population activity and also urban fast changes framework can change the past equations of urban spatial organization and make the cities faced with many problems in environmental, social and framework arenas with some uncertain problems. One of the most important problems in urbanization development is related to creation of informal settlements in contemporary cities heart. Creation and development of organization in the settlements were initiated during some stages and various factors influenced immigration. In current research we want to conduct a spatial organization survey in Tabriz metropolitan settlements with the effective factors on the creation and development of the phenomenon. Informal residents in Tabriz metropolitan area is as an important urban problems as black spot in Tabriz framework since 1961. This residence pattern is increasing rapidly in Tabriz city.
 
Methodology
Current research method is applied-theoretical according to study type and it is analysis – descriptive according to nature. For data analysis, we have used document –field (measurement) method. Development Tabriz metropolitan informal settlements have initially been investigated using documentary form and reference to the related statistics. For measurement of the effective factors in informal settlements organization and development, questionnaires have been distributed among the managers, administrators and urban experts. We have selected 110 persons as sample volume by using simple randomized sampling (Statistical population is 1400 persons), for data analysis, regression coefficient and numerical average tests and Friedman’s ranking average in SPSS and also plans preparation in GIS. For inside validity measurement in current research, at first context validity has been used to increase the questionnaire reliability.
 
Results and discussion
Background of informal settlements in Tabriz refers to 50 years and it is increasing to now. Tabriz role as a major place in history of Iran and the necessity to allowance in entering to this city lead to some effects on rapid development of informal settlements. Tabriz informal settlements not only didn’t have something to do with the industrial development, but also it returned to industrial era. Contemporary informal resident phenomenon in Tabriz city since 1961 improved at the beginning of agrarian reforms in Iran. Creation and installation of large industrial units and vacancy of rural centers increased rapid expansion of informal residence.
Generally, organizing informal settlements in Tabriz city is divided into 3 periods. Before 1960s because of Tabriz political position and increasing immigration of rural population to the city and inexpensive lands in urban outskirt and immigrant residence in improper lands, the informal settlements were developed in the suburb areas. Tabriz metropolitan informal settlements received the spatial organization and arrangement before agrarian reforms based on natural, political and social factors. After 1960s, the agrarian reforms, rural industrialization and fast immigration to Tabriz City, and also increase in oil price led to development of informal settlements in outskirt areas. After 1983, development and organizing of these informal settlements in Tabriz metropolitan and around villages declined due to partial accessibility to valid formal systems and house loan for low-income persons in informal parts in South and Southwest regions.
 
Conclusion
Based on Tabriz metropolitan political position and increase in immigration, informal settlement developed again before agrarian reforms. Immigration increase and Tabriz metropolitan population growth especially since 1966 resulted in financial inability of the residents to have a home in formal outskirt and urban legal areas. They provided informal lands for living in urban outskirt places. Main reasons for development of informal settlement and residence in Tabriz metropolitan is related to some factors including unbalancing in urban system and surrounding villages, unfair distribution of power resources, wealth and income in the city, lack of anticipation sufficient residential space and proper case for people with low income in urban framework plans and standards out of their ability, low accessibility for valid and informal systems and house loan for low income persons and weakness in urban management and people participation in planning and preparing patterns. Development of the settlements in Tabriz metropolitan shows that informal ranges in north part of the city have long-term experience against other ranges. South and Northwest ranges were created and developed after 1971 to recent years. Southwest ranges are related to urban development in recent years and are combined with the surrounding villages in Tabriz metropolitan.