Systematic analysis of primary and secondary mechanisms affecting air pollution in Tehran

Today, the world's population in 2018 is 7,632,819,325 billion. %54 of the world's population lives in urban areas and that trend is expected to increase to 66 percent by 2050. In other words, half of the world's population currently lives in cities, and %95 of population growth will occur in developing cities over the next 90 years. Until 1800, only %3 of the population lived in cities, and by 1900, less than %15 lived in cities. Among the problems of urban development is one of the most important risk of air pollution, which has greatly affected the lives of human societies and has caused a lot of costs in the field of health and urban management. According to the World Health Organization, 9 out of 10 people breathe polluted air, and it is estimated that 7 million people die each year as a result of environmental and household pollution. Iran in general and the metropolis of Tehran in particular are no exception to this rule, so that according to statistical data in 2017, 29,098 people died due to air pollution in Iran..The number of factors affecting air pollution based on the method and cases studied is 18 factors. These factors include, Natural factors, Fossil Fuels, Environmentally friendly technologies, Migration and population density, transportation and traffic, Planning and policy making, green space, Lack of proper budget allocation, Urban location and focus of administrative and commercial centers, Establishment of a factory in the west of Tehran, Improper expansion of the city and construction of urban highways, Weakness in waste management and landfill.

The philosophical foundations of research are interpretive. The research orientation is applied. In this research, the research approach is combined. The research method in this research is qualitative and quantitative .The research layer was in the form of field and library activities. The research strategy in this research is survey. The objectives of the research are descriptive and data collection procedures using questionnaires and documents. Also, data analysis tools in this research have been performed using Wizard scenario software.

For this purpose, first, the factors affecting air pollution in Tehran must be identified, which has been achieved in the previous stages. Also, the classification of factors into primary and secondary has been done by experts. The classification of primary and secondary factors is such that factors, natural factors, fossil fuels, environmentally friendly technologies, establishment of a factory in the west of Tehran, urban location and concentration of administrative and commercial centers and transportation and traffic are among the primary factors. And factors, migration and population density, expansion and growth of industry, home and industrial cooling and heating equipment, design and program and policy, cultural factors, high-rise construction, e-government, allocation of appropriate budget, uncontrolled expansion of the city and construction Urban highways, waste management and landfilling, agricultural and mining activities are among the secondary factors.In order to perform the analysis process, it is necessary to define different modes (descriptors) for each identified indicator or factor, because to work with Wizard scenario software, different modes of a factor must be specified, in order to be able to accurately analyze the previous conditions. After identifying its modes and descriptors, a cross-impact analysis questionnaire was designed, which was completed by 10 experts in air pollution. Each of them has a master's or doctoral degree in environmental and policy-making. Then, by taking the mode (frequency of the most selected number) from the answer sheet of the experts, the final numbers in the form related to the software are loaded. By placing the factors and descriptors in the Wizard scenario software as well as the descriptions related to the descriptors in the matrix in the data output software, the Wizard scenario software has provided 6,718,464 scenarios, of which only two The scenario is adaptable and exploitable.

The city of Tehran is facing the same problem. However, the issue that is of special importance in this regard should be considered from a trans-organizational point of view, and serious and fundamental attention should be paid to this institutionalized problem in Tehran, because the costs of preventing air pollution will be far less than treating and eradicating it. In fact, according to the results obtained from the Wizard scenario software, structurally, the most important primary factors affecting air pollution in Tehran, including urban location and focus of administrative and commercial centers, environmentally friendly technologies, natural factors, Fossil fuel is the plant's location in the west of Tehran and transportation and traffic. In this category, we have examined the primary impact mechanisms on the system. Of course, in addition to being effective on the system, each mechanism has a certain amount of passive on the system, and there is no absolute active or absolute passive. Among the primary active mechanisms of urban location and concentration of commercial administrative centers, it has the greatest active factor on the system, while on the least active on the system and the most passive factor is transportation and traffic. Also, the most important secondary factors affecting air pollution in Tehran in terms of structure, according to the analysis of the grade system provided by the software, can be design, program and policy, allocation of appropriate budget, migration and population density, e-government, Western factors, respectively. He pointed to the expansion and growth of industry, the uncontrolled expansion of Tehran and the construction of urban highways, high-rise construction, waste management and landfill management, green space, home cooling and heating equipment, and agricultural and mining activities. In fact, these secondary mechanisms represent a discussion of the direct effects on the system.