Abstract:
Background Acceleration in energy consumption and environmental degradation constrains economic development and degrades the quality of economic development. In 2012, China issued a new "Ambient Air Quality Standard" (GB 3095-2012), conducted real-time air quality monitoring, and publicized air quality reports for 74 cities including Beijing, Tianjin, and Hebei.
Objective This study is designed to understand the air quality, air pollutant levels, and their relationship with economic development in seven representative cities of China from 2014 to 2017.
Methods Air quality was described by air quality grade, air quality index (AQI), and main air pollutant concentrations, and the results were compared with the "Ambient Air Quality Standard" (GB 3095-2012). The relationship between air quality (AQI) and economic developmentannual per capita gross domestic product (GDP) was analyzed by environmental Kuznets curve (EKC). The relationship between industrial structure (added values of the primary, secondary, and tertiary sectors) and air quality AQI was analyzed by grey correlation analysis.
Results Shenzhen had the best air quality among the seven cities, with a lowest annual average AQI of 54.59 from 2014 to 2017. The days with good and moderate air quality in Shenzhen accounted for 95.8% of total studied days, and the polluted days accounted for 4.2%. Six main air pollutants in the seven cities exceeded national limits with varying degrees, especially PM2.5 and PM10. Among the seven cities, Tianjin had the most days (n=500) when PM2.5 was unqualified with the Grade 2 level, and Xi'an had the most days (n=454) when PM10 was unqualified with the Grade 2 level. The EKC results of Xi'an, Shenzhen, Nanjing, Tianjin, Chongqing, and Lanzhou were N-shaped, while the EKC of Wuhan was inverted N-shaped. Both per capita GDP and the added values of the three industries showed strong relationships with AQI, and annual per capita GDP showed the strongest relationship for all the seven cities.
Conclusion At present, the ambient air quality of the seven cities needs further improvement as main air pollutants exceed the national standard to different extents. The EKC of ambient air quality and economy is either N-shaped or inverted N-shaped. Annual per capita GDP and industrial structure have great impacts on ambient air quality.