Environmental Air Quality in Lanzhou City in 2014-2015

Objective To analyze the status of environmental air quality in Lanzhou city in 2014-2015.

Methods The monitoring data on the average daily concentration of air pollutants, including PM₁₀, PM_2.5, NO₂, CO, O_3-1h and SO₂ in Lanzhou during 2014-2015, were collected; the yearly, regional and seasonal characteristics in heating and non-heating season were analyzed, and then a comprehensive assessment was made.

Results The environmental air quality in Lanzhou city was improved. The concentration of PM₁₀, PM_2.5, CO and SO₂, was declined, the concentration of NO₂ and O_3-1h was increased. The concentration of air pollutants except O_3-1h in heating season was higher than that in non-heating season. The total concentration of pollutants was higher in the western urban area of Lanzhou in 2014-2015. The major pollutants in environmental air were PM₁₀, PM_2.5 and NO₂. The load factor of PM₁₀, PM_2.5, CO and SO₂ were declined, but that of NO₂ and O_3-1h were increased.

Conclusions The environmental air quality was improved gradually in Lanzhou in 2014-2015. The type of pollutants was different between heating season and non-heating season. According to the characteristics of major pollutants and contaminated areas, targeted measures should be taken to improve the quality of environmental air.