[Spatial and Temporal Distribution Characteristics and Fugitive Dust Emission of Building Sites in Beijing]

Because of the continuous expansion of the city and the evacuation of non-core functions, the city pattern of Beijing has gradually changed in recent years. Based on many construction projects, building sites are widely distributed within the city. Therefore, fugitive dust emission is an important factor affecting the air quality in Beijing. This article focuses on the plain area in Beijing. Remote sensing was used to extract building sites from 2013 to 2017, analyze the spatial and temporal distribution characteristics of the building sites, estimate the fugitive dust emission, and propose a grid-based emission classification management program. Research shows that the building sites form a belt surrounding the central urban area, mainly distributed in the urban-rural integration area. From 2013 to 2017, the area of the building sites first decreased and then increased. After 2015, the center of the building sites in Beijing shifted to the southeast and started to show an uneven distribution. The area of the building sites is positively correlated with the PM₁₀ concentration. The correlation coefficients of 23 automatic ground monitoring stations are all above 0.80. Combined with the building site activity levels and emission factors, the estimated air pollutant emissions of TSP, PM₁₀, and PM_2.5 from building sites in 2017 were 39.5×10⁴, 19.4×10⁴, and 4.0×10⁴ t, respectively. The emission intensity of the pollution in the grid has developed towards polarization, which further increased the emission intensity of high-strength pollution grids. Based on standardized PM₁₀ grid emissions of building suites, the plain area of Beijing can be divided into five categories:lower pollution, low pollution, medium pollution, high pollution, and higher pollution.