Research on the impact of land use and meteorological factors on the spatial distribution characteristics of PM2.5 concentration

Precisely capturing the spatial distribution characteristics of fine particulate matter (PM_2.5) is the key to air pollution prevention and control. Researches suggests that PM_2.5 concentrations is jointly affected by meteorological factors and urban land use. This study comprehensively considered these factors, with land cover, meteorology and road traffic as potential independent variables. The land use regression (LUR) model was used to identify the main influences on the spatial distribution of PM_2.5 concentration under different types of land use, and the importance of these factors was assessed using a random forest (RF) model. The research findings indicate that: (1) The fluctuations of PM_2.5 concentration in residential and industrial land use are relatively severe, ranging from 0 to 50 μg/m³. The changes in commercial and public service land use range from 0 to 40 μg/m³. And the in green space range from 15 to 33 μg/m³ (2) The distribution of PM_2.5 concentration in residential land is primarily influenced by precipitation and relative humidity, with relative importance of 36.3% and 23.9%, respectively. And that in industrial land use is primarily influenced by wind speed, with a relative importance of 30.6%. (3) The most influential determinant of spatial distribution of PM_2.5 concentration is meteorological factors, with relative importance exceeding 62%. The relative importance of road traffic ranges from 15.6% to 24.9%. And that of land cover factors ranges from 9.9% to 22.4%. This study analyzes the coupling connection between urban land use and spatial distribution of PM_2.5 concentration, and elaborates the specific influence of the former on the latter.