Based on the monitoring data from national and provincial ambient air automatic monitoring sta-tions in Yongzhou,Hunan from 2016 to 2020,the evolution characteristics of ambient air quality in typical multi-provincial border region were investigated by HYSPLIT model,potential source contribution factor method and concentration weight trajectory analysis.The results showed that during the 13th Five-Year Plan period,the average proportion of days with good air quality in 11 districts of Yongzhou was 93.0％,the ambient air qual-ity comprehensive index ranged from 2.90 to 3.46.The concentration of SO2,PM2.5 and PM10 had an obvi-ous decreasing trend.External transport was mainly affected by long-distance transportation of pollutants in the northeast and short-distance transportation in the south.From October to next March,it was mainly affected by air mass from the northeast and southwest.The number of short-distance tracks accounted for 71.6％,and the long-distance tracks accounted for 28.4％.Heavily polluted weather was mainly affected by short-distance transportation of air mass from Changzhutan in Hunan and neighboring Guangxi and Guangdong prov-inces,with contribution rates of 31.8％and 31.4％,respectively.
关键词
环境空气质量/后向气团轨迹/多省交界区域/永州市
Key words
Ambient air quality/Backward air mass trajectory/Multi-provincial border region/Yongzhou
万方数据