Influence of Road Patterns on PM2.5 Concentrations and the Available Solutions: The Case of Beijing City, China

With the increase in urbanization and energy consumption, PM2.5 has become a major pollutant. This paper investigates the impact of road patterns on PM2.5 pollution in Beijing, focusing on two questions: Do road patterns significantly affect PM2.5 concentrations? How do road patterns affect PM2.5 concentrations? A land-use regression model (LUR model) is used to quantify the associations between PM2.5 concentrations, and road patterns, land-use patterns, and population density. Then, in the condition of excluding other factors closely correlated to PM2.5 concentrations, based on the results of the regression model, further research is conducted to explore the relationship between PM2.5 concentrations and the types, densities, and layouts of road networks, through the controlling variables method. The results are as follows: (1) the regression coefficient of road patterns is significantly higher than the water area, population density, and transport facilities, indicating that road patterns have an obvious influence on PM2.5 concentrations; (2) under the same traffic carrying capacity, the layout of “a tight network of streets and small blocks” is superior to that of “a sparse network of streets and big blocks”; (3) the grade proportion of urban roads impacts the road patterns’ rationality, and a high percentage of branch roads and secondary roads could decrease PM2.5 concentrations. These findings could provide a reference for the improvement of the traffic structure and air quality of Beijing.