پژوهشهای اقتصادی (Sep 2024)
Urban Morphology and Public Transportation Demand with Special Emphasis on the Form of Urban Road Network
Abstract
Introduction In recent years, the ever-increasing population growth and rampant use of personal transportation and daily trips have caused many problems in the field of transportation, including high fuel consumption, air pollution, noise, high density streets, reduced physical activity, etc. In many metroplolitan areas during the past decades, the sudden increase of motor vehicles has caused heavy street traffic in intra-city trips, and the main reason for this can be considered the weak relationship between urban morphology and transportation, in other words, urban forms that avoid pedestrians and encourage motor trips. Urban morphology is one of the most important and main factors that affect the demand for urban transportation. The quality of land use (density of residential units or their dispersion) forms the important basis of urban morphology. In the formation of urban morphology, natural and human factors play varried roles, among them road network is of paramount importance in construction and morphology of a city. Since urban morphology has a significant effect on urban transportation, how to establish a strong relationship between urban morphology and travel modes has has always been of great interst of researchers. This study is aiming at investigating the impact of morphology characteristics on urban transportation demand. In this research, features of urban morphology, such as overall residential density, connectivity index, and the average width of roads, with the help of demographic characteristics, such as population density, female and female working poulation, total working population etc., on demand for urban transportation have been ivestigated. These include four parameters such as creation of public and personal trips and attraction of public and personal trips on in 186 traffic areas of Isfahan city. Methodology This research has been conducted with a descriptive causal approach based on the data and information required in the study areas. To achieve the research goals, 186 traffic areas of Isfahan City have been studied. For analyzing the characteristics of urban morphology, including average width of roads, overall residential density, and connectivity index (street density), in the form of GIS maps have been investigated, and for demographic characteristics, the population and housing census map of Isfahan City was obtained and researched from the Deputy Planning and Human Capital Development Organization of Isfahan Municipality. Then, using the map of 186 traffic areas of Isfahan City, the amount of these variables was calculated and extracted by GIS software. Moreover, the information related to urban transportation demand based on public transportation demand, including public travel creation, public travel attraction, and personal transportation demand, including personal travel creation and personal travel attraction from the origin-destination matrix of the year 2021 of Isfahan city on a normal working day and at the peak hour of 7:00 to 8:00 a.m., the transportation and traffic department of Isfahan municipality has been obtained and used for evaluation. In the present research, in order to reach a complete and comprehensive answer, after extracting the data from GIS software, the Eviuse software was used. According to the number and nature of the research variables, the specification of the model is done using the multivariate regression method and the weighted least squares method. GIS software was also used for drawing the maps. Findings The research findings show that in the TSS and JSS models, with the increase in the average width of traffic areas, the creation and attraction of personal travel have also increased, and in the TSO and JSO models, the creation and attraction of public travel have decreased with the increase in the average width of traffic areas. In TSS model, the coefficient is negative and in JSO model, the coefficient is positive, which shows that with an increase in the overall residential density, the use of private transportation decreases and the use of public transportation increases. In terms of street density, which also indicates the connection index, the coefficient value is positive in TSS and negative in TSO model. The results also show that women in general use public transportation, but working women use private transportation more. The estimation of TSS model shows that as population is aging in the traffic areas of Isfahan City, the preferrence in using personal transportation has been rising. In JSS model, the parking variable has a direct relationship with the attraction of personal travel. In the personal travel attraction model, health-therapeutic use and commercial use have a direct relationship with the attraction of personal trips, and in the public travel attraction model, commercial, educational, and health-therapeutic uses have a direct relationship with the attraction of public trips. Finally, the increased number and variety of the users will also increase intra-city trips. Discussion and Conclusion In this research, an attempt has been made to investigate the effect of urban morphology variables on urban transportation demand with a general perspective. The results of the estimation of the research models show that the widening of urban roads as a management policy for intra-city travel demand increases people's trips using personal transportation and as a result, increases the number of road users. Street density, which indicates the number of higher streets and therefore greater connectivity, has a direct relationship with citizens' use of private transportation. Residents of areas that have higher overall residential density and population density, which indicates denser urban fabric and more dispersion, are less likely to use personal transportation, and people in those areas prefer to use public transportation and walking options. Also, as the age of the residents of the area increases, they use private cars for their daily trips. Another examination of the results of the research indicates that areas with parking facility, will attract passengers who have used private transportation compared to the areas that do not have such possibility. In general, as the total working population increases in the areas, they use personal transportation to go to their workplace, and it can be said that the female population uses public transportation more for their daily trips. In the public travel attraction model, the positive coefficient of commercial use is higher than the coefficient of health-therapeutic use and educational use, and with the increase in the number of commercial uses, the attraction of public travel increases to a greater extent. In the personal travel absorption model, the effect value of the healthcare usage coefficient is higher than the commercial usage coefficient and it shows that with the increase in the number of healthcare usages, the absorption of personal travel will increase. Moreover, the increased number and variety of the users will also increase intra-city trips.
