Assessing the Impact of Urban Streets Networks Connectivity on Vehicular Movement and Urban Air Quality for Lahore City, Pakistan

Urban environment is considered as a complex system comprised of physical, social, economic and environmental features and activities. With the passage of time, after realising its contribution in changing the function and morphological pattern of cities, researchers are keenly interested to explore the relationship of its physical component among social, economic and environmental activities. Among all physical components, buildings and street networks are considered as main morphological elements of urban cities. By keeping in view, the above illustrated importance of urban environment: different component, this research study has been planned to carry out for a city of Lahore, Pakistan by focusing physical built environment, particularly urban street networks and its associated impacts on vehicular movement in addition to urban air quality. Street networks are being considered as facilitator of the human movement in a city based on its capability to join or to segregate different parts/areas of city and this feature of urban street networks is strongly dependent on degree of accessibility of street networks. As accessibility is very vast concept and have different definitions which are used according to research objectives of the study. For this research study, accessibility is considered in terms of integration (closeness of one street to another street) and choice (street which is likely to pass through while moving in a city) of urban street networks. These accessibility measures are used as a determinant to describe the extent of urban street networks connectivity of a city, measured through axial lines (number of turns: topological point of view) using space syntax as a measuring tool. From applications of space syntax in different field like crime, land particularly in transportation sector, it is considered a good predictor of pedestrian as well vehicular movement. In this research, it is used to investigate the extent of influence of urban street connectivity on vehicular movement as well as on urban air quality by finding out relationship of integration and choice with vehicular movement first, and then determining the relationship of vehicular movement with urban air quality through research model 1 (Urban Street Connectivity and Vehicular Movement) and research model 2 (Air Pollution with Urban Street Connectivity in terms of vehicular Movement) by using multiple regression and simple linear regression as a statistical analysis methods. From the results of first part of research study, it is examined that there is a significant relationship exists between vehicular movement and urban street connectivity shows that approximately 48-50% of the variance in traffic flows is accountable by the urban street connectivity for the city of Lahore, Pakistan. Outcomes of the statistical analysis also demonstrate that choice_Nor has a slightly greater impact on vehicular movement as compared to integration. Furthermore, second part of the research study based on research model 2, in this case urban street connectivity is taken in account in terms of vehicular movement and PM10 as indicator of urban air quality. Results explained that only 20% variance is occurred in PM10 concentration due to vehicular movement which shows a very weak relationship between urban street connectivity in terms of vehicular movement and urban air quality. Due to unavailability of data for controlled variables they are not taken in account during analysis and considered as a limitation of research study. Therefore, it is recommended to do the same research for same city under similar circumstances by collecting the data of control variables to analyses how significantly other variables have an influence on vehicular movement and on urban air quality along with urban street connectivity. It is also suggested to perform the same research by taking in account geometric analysis for urban street connectivity to explore the difference in results among both type of analysis and discover which analysis best fits to describe the vehicular movement flow.