The prevention and control of air pollution in the Qinghai-Tibet Plateau(QTP)is imperative to meet the goals of the Blue-Sky Protection Campaign,to protect the ecological security barrier,and to achieve high-quality and sustainable economic development.Based on the long time-series fine particulate matter(PM2.5)data with a high spatial resolution,the spatial autocorrelation model was adopted to analyze the static spatial correlation characteristics of county-scale PM2.5 concentrations in the QTP.Furthermore,the dynamic evolution and long-term transfer trend of PM2.5 distribution were explored by combining traditional and spatial kernel density estimation.Finally,the spatial Markov chain model was used to characterize the spatial transfer characteristics of county-scale PM2.5 concentrations in the study area.The results showed that:(1)On the county scale,the PM2.5 concentrations started with a higher value,and the spatial lock-in characteristics were significant.PM2.5 emissions were high in the following areas:southern Xinjiang,and Qaidam Basin,Xining city,and Haidong city of Qinghai province.(2)The county-scale PM2.5 concentrations presented significant spatial correlation characteristics,and the local spatial correlation was mainly dominated by two homogeneous spatial correlations:H-H and L-L.(3)The PM2.5 concentrations in counties of the QTP showed an overall decline in the distribution and dynamic evolution,and the local differences were still large.Furthermore,there was a"club convergence"phenomenon when spatial conditions were not considered.When the spatial influence of adjacent regions was considered,the spatial convergence pattern and significant spatial positive correlation were presented.Under the condition of a three-period time lag,the"siphon effect"in the area with high PM2.5 concentrations was enhanced.Additionally,the results revealed that the combined effect of PM2.5 emissions from different regions would affect the future spatial distribution of PM2.5 in the QTP.(4)The spatial transfer trend of PM2.5 concentrations was stable at the county level,and it is difficult to realize the jump transfer in the level of county units.This study provides a theoretical reference for identifying the spatial dynamic evolution characteristics of PM2.5 concentrations in the QTP on the county scale and implementing targeted air pollution prevention and control measures to construct ecological civilization in the plateau region.
PM2.5spatial correlationdynamic evolutionspatial dynamic kernel density estimationQinghai-Tibet Plateau
NETL
NSTL
万方数据
