Geographical Detection of Spatial Heterogeneity and Drivers of PM2.5 in the Yangtze River Economic Belt

Abstract

Based on ground monitoring data, we explored the spatiotemporal characteristics and drivers of PM2.5 in the Yangtze River Economic Belt (YREB) in 2018 using spatial autocorrelation analysis and geodetector modeling methods. The results showed that:① the PM2.5 concentration in the YREB posed the obvious characteristics of low values in summer and high values in winter, seasonal variation in spring and autumn, monthly U-shaped variation, and daily pulse variation. The low value area was mainly concentrated in the south bank of the upper reaches, whereas the high value area was located in the north of the middle-lower reaches of the YREB. ② PM2.5 pollution in the YREB had a stable positive spatial correlation, and the local association pattern showed a significant HH and LL spatial convergence. ③ The spatial correlation of PM2.5 in the YREB decreased with the increase in geographical distance, and its spatial autocorrelation threshold was approximately 870 km, within which the spatial agglomeration of PM2.5 pollution was strong. ④ The influences of natural and anthropogenic factors on PM2.5 had significant spatial differences. Altitude, relief, and population density were the high impact factors of PM2.5 pollution in the YREB. The interaction of factors had a far greater explanatory power on PM2.5 pollution than that of single factors. The dominant interaction factor was industrial structure ∩ altitude, which reflected the complexity of the drivers of air pollution in the YREB.