Variations in air quality during rapid urbanization in Shanghai, China

Shanghai is the largest commercial and industrial city of China, but air quality issues have hindered its development in becoming a "global city." This study used monitoring data on SO₂, NO_x, acid rain pH, dustfall, and total suspended particles (TSP) from the Shanghai Environmental Monitoring Center to evaluate and analyze the air quality in urban, suburban, and rural areas during the period 1983-2005. The results showed that the spatial pattern of air parameters was determined by the level of urbanization; thus, the higher the level of urbanization, the worse the air quality. On the whole, the atmospheric environment of the three spatial regions improved gradually because of economical growth and environmental protection since the 1990s. For the entire region of Shanghai, the relationship between the integrated air quality index and gross domestic product (GDP) per capita was an N-shaped environmental Kuznets curve (EKC) due to decreasing air quality in suburban and rural areas this century. Thus, environmental controls should be increased in Shanghai, especially in developing suburban and rural areas during rapid urbanization.