كليدواژه :
نظام شهري , نخست شهري , تمركز , تعادل , منطقه شمال
چكيده لاتين :
Introduction
The urban system is a set of interconnected cities and towns that have been found within a particular territory. Urban system is a set of affiliated cities that create the structure of urban settlements in a region, region, country and the world. The urban system is not limited to an array of urban settlements, but also streams and connections between these settlements. These flows are: population, capital, factors of production, ideas, information and innovation, and their dynamism depend on the level of movement of goods, services, thoughts and population movements between settlements and rural areas. In fact, the dependence and relationship of the settlement they constitute one of the most important features of urban systems. The change in urban systems is a continuous process that simultaneously occurs at different levels of space. Due to the importance of urban systems, most urban and regional planner’s strategies, such as top-down focusing approaches, as well as low-level decentralization approaches have been undertaken to balance urban systems. Studies show that the spatial distribution of population and activity in the urban system of developing countries has been more unbalanced and unequal than developed countries. Evidence shows an increase in the population of cities, a disturbance in the balance of the urban network, and the emergence of the urban primary pattern in Iran. On the other hand, the lack of logical connection between cities of different levels has caused the inefficiency of urban systems at the regional and national levels. In this regard, the north area of the country has not been an exception to this rule. Over the past few decades, the rapid growth of urbanization and the increase of urban population in this area has accelerated, and the urban system seems to have led to spatial imbalance. Based on this research, the urban system of the north area of the country from 1956 to 2016 has been studied and analyzed. Given that such a study is being conducted for the first time in the north area of the country, it may be considered an innovation. The evaluation and analysis of urban systems shows the policies and the distribution of population in the territory. By studying this, the distribution and the amount of equilibrium in population distribution become clearer. The government's actions in regional planning, decentralization, and strengthening small and medium-sized cities over the past decades have yielded mixed results. Familiarity with the existing urban system of the north area of the country and comparing it with previous periods, the spatial consequence of government decisions and the movement of the population in the area of this area will determine. In fact, the study of the urban system of the northe area of the country shows the movements of capital, labor and population in the territorial area of this region between different urban classes. The main purpose of this study is to identify quantitative and population changes in the urban system of the north area of the country during the years 1956 to 2016 using different models, to determine the balance of the urban system of the north area.
Methodology
The research method of this research is descriptive-analytical and practical in terms of purpose. Library resources have been used to codification theoretical foundations and the results of general population and housing censuses of the country during the years 1956 to 2016 have been used to collect data. The statistical population includes all urban areas of the north area of the country in the period 1956 to 2016. In this research, using Excel software, while classifying the population data of urban areas been paid to study the urban system of the north area of the country using the indexes urban primacy includes primate city, tow city, Ginsberg, Mehta, moomaw and alwosabi, dominance mosavi and indexes centralization includes herfindahl and Henderson and indexes Balance includes entropy, coefficient of variation, rank-size.
Results and discussion
The results of urban primary indicators and concentration indicate that urban primary and concentration rates have been declining from 1956 to 1986, but from 1986 to 2011, the trend has risen until it rebounds slightly in 2016. The results of balance indicators also indicate that the imbalance in the spatial distribution of population in the urban system of the region has been continuously increased from 1956 to 2016. The results of the rank-size indicators also indicate that there is a significant difference between the actual population and the desirable population of the cities of the region during the studied years and as well as the relative importance of the intermediate cities from 1956 to 1976 and the urban primary dominance from 1976 to 2016.
Conclusion
According to that two main reasons for the imbalance in the urban system of the area migration from village to city and conversion of villages of the center of the district with any size of population to the city, the planning strategies of the regional development plan for strengthening the economy and develop job opportunities in the villages as well as the amendment of the village-to-city conversion law, taking into account the minimum population criterion for the conversion of the village into the city are provided.
