Dynamic Monitoring and Evaluation of Environmental Air Pollution in Zigong

Objectives To explore the dynamic situation of urban air pollution, evaluate air quality, and provide evidence for prevention and control of air pollution in Zigong.

Methods Three monitoring points were selected according to the national urban air pollution monitoring standards, and automatic analytical method was used for real-time automatic online monitoring of SO₂, NO₂, CO, O₃-8 h, PM₁₀ and PM_2.5 at each point every day. National and provincial monitoring platforms were used for data transmission, summarization and processing. Descriptive statistical analysis was used to analyze the monitoring result.

Results PM_2.5 was the primary pollutant and its pollution level was over the standard. PM_2.5 and PM₁₀ were dominated in winter, spring and autumn, but O₃-8 h was dominated in summer. The number of excellent AQI (Class Ⅰ) days increased from 25 in 2014 to 73 in 2018.

Conclusions There were PM_2.5, O₃-8 h, PM₁₀ and NO₂ pollution in the air of Zigong city from 2014 to 2018, but the air quality has been improved year by year.