Spatial distribution characteristics of PM2.5 and PM10 in Xi'an City predicted by land use regression models

PM2.5 and PM10, could increase the risk for cardiovascular and respiratory diseases in the general public and severely limit the sustainable development in urban areas. Land use regression models are effective in predicting the spatial distribution of atmospheric pollutants, and have been widely used in many cities in Europe, North America and China. To reveal the spatial distribution characteristics of PM2.5 and PM10, in Xi'an during the heating seasons, the authors established two regression prediction models using PM2.5 and PM10, concentrations from 181 monitoring stations and 87 independent variables. The model results are as follows: for PM2.5, R-2 = 0.713 and RMSE = 8.355 mu g/m(3); for PM10, R-2 = 0.681 and RMSE = 14.842 mu g/m(3). In addition to the traditional independent variables such as area of green space and road length, the models also include the numbers of pollutant discharging enterprises, restaurants, and bus stations. The prediction results reveal the spatial distribution characteristics of PM2.5 and PM10, in the heating seasons of Xi'an. These results also indicate that the spatial distribution of pollutants is closely related to the layout of industrial land and the location of enterprises that generate air pollution emissions. Green space can mitigate pollution, and the contribution of traffic emission is less than that of industrial emission. To our knowledge, this study is the first to apply land use regression models to the Fenwei Plain, a heavily polluted area in China. It provides a scientific foundation for urban planning, land use regulation, air pollution control, and public health policy making. It also establishes a basic model for population exposure assessment, and promotes the sustainability of urban environments.