عنوان مقاله [English]
This research from the methodology aspect is the descriptive-analytic and categorized in the development - applied type. The required data were collected using library and documentary studies. Environmental, social and physical criteria were identified in 12 variables. Then, by preparing the layers of each criterion, we defined the weight of each layer based on its importance in the infill development analysis. In this study, the Analytical Hierarchy Process (AHP) was applied by Expert choice software for prioritizing, the weighting of criteria and fuzzy multivariate analysis model in GIS environment for production, weighting, and fuzzy combination of layers were used. Finally, using the weights obtained from AHP Analysis, the suitability map for infill development of uremia was prepared using Fuzzy Overly extending in ArcGIS software and the exponential population growth model and land per capita are used to predict the amount of land that could be effective for preventing urban growth sprawl using infill development option. The results showed that from the total of 5502.6 hectares of Uremia, 367.83 (6.69%) of the land quite suitable, 863.55 hectares (15.71%) of land medium suitable, 1448.91 hectares (26.33%) somewhat inappropriate, 1721.25 hectares (28.31%) inappropriate, and 11.61% (20%) are totally inappropriate and the amount of land that can be increased by the applying of an infill development strategy for preventing of urban sprawl growth estimated at 3680000 square meters in the 1405.
Introduction:Today, the sprawl growth of cities has led to the encroachment to precious agricultural lands and the disproportionate distribution of urban services that the, it also provided the basis for the instability of the urban environment. In the meantime, infill development by focusing on urban vacancy lands and old and worn-out fabric for development can reduce sprawl urban growth.Therefore, in view of the above mentioned necessities, this research was conducted with the aim of measuring the capacities of infill development in Urmia urban. It has been formulated in response to two main questions, What opportunities and capacities does Urmia have for infill development? And in the horizon of 1405, to what extent can urban sprawl be prevented by focusing on infill development?
Methodology:The present research is descriptive-analytical method and has a developmental-applied nature. Various sources such as websites, books, articles, etc. have been used to study the literature related to the research. Secondary data were also obtained through documentary studies using the Urmia Master Plan studies and other documentary studies. In this research, AHP in Expert choice software was used to prioritize and weight the criteria and from Fuzzy Multivariate Analysis in GIS Software Environment to Generate, Weight, Fuzzification, Integrate and Overlay Layers and an exponential growth and land per capita model was used to predict the role of infill development in preventing peripheral growth in the 1405 horizon.
Results and Discussion:In this research, after knowing the general principles of infill development considering the natural environment and man-made conditions of Urmia urban and the Literature review and studies on the subject of research, determination of infill development indices in Urmia urban as a case study was paid. These criteria are in the form of natural, social and physical criteria in the form of 14 criteria (slope, slope direction, distance from flood path, distance from the fault, distance from the river, distance from military range, distance from main roads, number of floors, age of buildings, Quality of buildings, distance from educational, medical and green spaces centers, zoning) were determined. The hierarchical analysis method was used to weight the identified criteria and sub-criteria. Weighting and prioritization of criteria and sub-criteria were done using experts' opinions in different organizations of Urmia urban. According to the results of this weighting, the highest weight belongs to the building quality criterion. After that, the number of floors has the highest weight. Also, inconsistency coefficient in this weighting is 0.07. The basic layers related to natural, social and physical indicators identified were obtained from governmental organisations, municipal and master plan of Urmia urban. A then prepares, for extraction and new layers prepare in GIS environment done. The following related Information Layers were generated using digital information and GIS databases based on the final weight of the criteria obtained by AHP hierarchical analysis. Next, standardization of each layer was performed using fuzzy functions by Fuzzy Membership plugin in GIS environment and Based on this, standardized fuzzy maps for each criterion were prepared. In this step, Fuzzy Overlay Spatial Analysis plugin was used to integrate and overlap fuzzy maps created in GIS environment and using three levels of fuzzy gamma (0.9, 0.8 and 0.7), three land suitability maps were prepared for infill development in Urmia urban and among them a layer (with 0.8 gamma) indicating the capability and suitability of city limits lands for infill development and it was closer to the realities of the lands of Urmia urban. selected. Also in the next, different parts of Urmia urban were identified as suitable and unsuitable lands for infill development using Intersect and Reclass functions by dividing the land into 5 range completely inappropriate, inappropriate, partially inappropriate, appropriate and completely inappropriate on the map and the area of each was calculated in hectares and square meters. An exponential growth and per capita model was used to measure the role of infill development in preventing urban peripheral growth in the 1405 horizon. For this purpose, we first calculated the growth rate between the years 2011 to 2016 (1.1%) and then based on the growth rate obtained, the population of Urmia urban in 1405 by exponential growth formula where Pt is the population of the destination year, Po the population of the year of origin, r the growth rate and time interval is between years, 837147 people were predicted. Next, using the population and per capita land (98 square meters), the urban area was calculated in 1405 (118291000 square meters) (area = per capita * population). Finally, the rate of development of the urban during the next 10 years was determined by the above calculations (17291000 hectares) and also the amount of land that can be considered as reserve land by implementing infill development and there by reducing the peripheral development of the urban, an estimated 3680000.
Conclusion: The results show that most of the lands of Urmia urban are 77.61% in inappropriate group, so that, partially inappropriate lands with 26.33%, inappropriate lands with 28.31% and totally inappropriate with 20% is dedicated to himself. Suitable land group is also in the next category with 22.39%, so that, completely suitable and suitable lands is dedicated to himself with 6.68% and 15.69%, respectively. Also, according to the final result, whatever we move northeast of the urban of Urmia towards its center and southern parts, the land suitable for infill development is reduced. Therefore, most compatible and suitable for redevelopment and infill development are located in the northeast fabric and the least adapt in the southwest fabric and river bed. Results of the analysis performed to predict the amount of land that can be saved by implementing infill development on the horizon of 1405 in Urmia urban and by doing it, slowed the peripheral growth of the urban, estimated 3680000 square meters. This amount of land indicates that storing it can significantly prevent sprawl urban growth and there by prevented the loss of precious urban land, which is usually allocated to agriculture to provide for the food of citizens, and so on and it also protects the urban environment.