Spatial and Temporal Trends of PM2.5 Concentration in Wansheng Economic Development Zone in Chongqing from 2006 to 2023

PM2.5 is fine particulate matter with a diameter of 2.5 microns, which can penetrate deep into the respiratory tract and alveoli, causing respiratory and CVD, and thus leading to premature death. Remote sensing technology can break through the limitations of ground monitoring stations to achieve seamless monitoring of the region, clearly presenting the gradient of spatial distribution of PM2.5 concentration and identifying pollution hotspots. This paper analyses the changes of PM2.5 pollution in Wansheng Economic Development Zone (WEDZ), from 2006 to 2023 based on the PM2.5 data in China High Air Pollutants dataset, in terms of the temporal evolution pattern, the spatial distribution characteristics, and its spatial centre of gravity migration, respectively. The results show that on the time scale, PM2.5 pollution in the study area shows a U-shaped trend, with higher concentrations at the beginning and end of each year, and with obvious seasonal characteristics, high in winter and low in spring; spatially, PM2.5 concentrations in the WEDZ are high in the northwest and low in the southeast; the spatial centre of gravity of PM2.5 concentrations fluctuates in different years, but the overall trend shows a slow migration towards the northwest, reflecting that the centre of gravity of pollution is gradually moving away from the central living area. The total spatial and temporal distribution characteristics changed dramatically with time, indicating that the overall air quality in WEDZ is getting better year by year, and the air pollution management measures have achieved certain results.