Road construction and air quality: Empirical study of cities in China

Traffic-related air pollution has become an urgent problem in many developing countries with rapid industrialization and urbanization. Traffic infrastructure construction, especially road reconstruction, is a prominent instrument of improving the road capacity and then affecting air quality. We employ the road area as the proxy variable of road infrastructure construction and further divide the road reconstruction pattern into lengthening pattern and widening pattern, respectively to evaluate the impact on urban air quality. The empirical result shows that the coefficient of road infrastructure construction represented by the road area is between −0.0818 and −0.0905, which means increasing road area has an emission-alleviating effect on air pollution. Moreover, we also find that the effect of road lengthening on air quality is better than road widening in the eastern China, but the improvement of road widening in the Central and Western China is better than the road lengthening. The result provides a valuable reference for policy recommendations on urban road infrastructure planning to improve air quality.