The trend of changes in air quality index (AQI) in Mashhad using ‎GIS

Mashhad is one of the largest city in Iran which heavy transport vehicles and industries is threaten air quality. The aim of this study was to evaluate the changes in air quality index (AQI) from 1391 to 1393 spring seasons and zoning with ArcGIS.
this study is descriptive, the spring of 1391 to 1393 PM10, PM2.5, NO2, SO2, CO and O3 were evaluated for AQI index at four online stations in the city and then classified air quality into six group’s daily include good, moderate, unhealthy for sensitive people, unhealthy, very unhealthy. Zoning was done with ArcGIS.
The most average on days of air quality obtained in good condition and has been responsible for PM2.5 and NO2 emissions is these days. According to the zoning maps AQI values in 1391 to 1393 years gained in Sadaf station the northwest of Mashhad in good condition but center and south of Mashhad was more polluted. AQI index values between 1391 and 1392 from April to June, have improved but the air quality has dropped in 1393.
The air quality in Mashhad city in the crowded southern and center city is unhealthy in some spring days, so in next years for pollution control, traffic management, changes in fuel quality, management of home heating systems, use of electric transportation will be needed.