Causes and consequences of sprawl in the central city- region of Mazandaran

The central city-region of Mazandaran Province, including the cities of Sari, Qaemshahr, Babol, and Amol, contains more than 53% of the population in only 30% of its area. Based on the set of issues that the spatial patterns of sprawling have brought about in the central city-region of Mazandaran Province, a research gap seems to be there in the presentation of a conceptual model of the relations governing the causes of sprawling and the consequences in this city-region. This research attempts to take an effective step in that regard.

Theoretical Framework:

There are two perspectives on the issue of sprawling: spatial and non-spatial. From the spatial point of view, issues such as land use changes, housing and land demands, transportation and infrastructure development, and inefficient land development have been raised, which directly or indirectly affect the causes and consequences of sprawling. From the non-spatial point of view, on the other hand, socio-demographic, economic, environmental, and management and supervisory system issues are discussed, the impacts of which on the causes and consequences of sprawling cannot be ignored. In line with the diversity in the spatial patterns of this type of growth in the urban and regional space, the causes of occurrence and the consequences arising from the spatial patterns of sprawling are different, an issue that is controversial due to the dynamic nature of the phenomenon. If sprawling is accompanied by poor control and supervision, there will be many negative consequences such as development inefficiency, extensive change in land use, destruction and waste of natural lands, excessive growth, increase in land and housing prices, formation and prosperity of temporary residence and second housing patterns, unplanned formation of residential centers, spatial imbalance, change in peri-urban and rural landscape, and combination of urban and rural boundaries. This causes many more issues in the physical and spatial subsystem of the planning environment and also has negative effects on spatial development processes.

The purpose of this study is to investigate the causes of sprawling by planning subsystems and to analyze the consequences of sprawling and achieve the underlying, causal, and continuity conditions in the city-region under study. This applied descriptive-analytical survey adopts a library-documentary method of data collection.

In the first part, the experts were provided with a questionnaire on the variables affecting sprawling extracted from studies around the world using purposive sampling, and the results were then analyzed using the fuzzy Delphi method. In the second part, structured interviews were made with the experts in the grounded theory system using the MAXQDA software, and they were then reviewed, analyzed, and coded. To investigate the causes of sprawling, 38 variables on 6 factors were provided to 25 experts who were selected based on purposive sampling. We used semi-structured interviews with 34 participants in the study area in order to analyze the consequences of sprawling, studied the spatial consequences of sprawling in the city-region, and specified 249 initial codes and 28 focal codes. Then, we formulated with the technique of continuous comparison the underlying conditions of development and economic structure change, the causal conditions of the inefficiency of the management and supervision system, the conditions to continue the transformation of the local community and destroy the natural structure, the consequences of change in the physical and spatial structure of the extraction area, and the grounded theory of the consequences of sprawling.

The most common causes of sprawling in the study area include per capita household income, land and housing trade, and land prices. In the analysis of the consequences of sprawling, we explained the background conditions for economic development and restructuring, the causal conditions of the inefficiency of the management and supervision system, the conditions of continuity including the transformation of the indigenous community and the destruction of the natural structure, and the consequences of physical and spatial restructuring of the region. To interrupt the process of formation and reduce the negative effects of sprawling, proposals were made on attempts to regulate and reform the decision-making structure, apply economic policies and adjust the market, slow down the accelerated process of destruction of the natural environment, improve the structure of regional planning (draft a codified, updated land use plan, apply detailed policies and ones to avoid promotion of land speculation, avoid provision of construction and building permits for peri-urban lands in the study area, partition natural lands and prioritize future developments in low-value lands, adopt approaches to endogenous development, development in brown lands, and intermediate development, and achieve a sustainable local society.