2016年长沙市环境空气质量的“周末效应”及“假日效应”

通过获取2016年长沙市连续在线观测得到的PM₁₀、PM_2.5、NO₂、O₃、CO和 SO₂逐时浓度资料,对工作日、周末、节假日（尤其是春节）的空气质量优良天数、污染物浓度变化特征进行对比分析,长沙市2016年6项污染物均表现出一定的"周末效应"现象,周末日平均浓度均低于工作日及全年的日平均浓度,其中PM_2.5最为明显;PM₁₀和PM_2.5浓度均星期一最高,星期六最低,CO和 SO₂浓度周末也均处于相对最低水平,NO₂和O₃在周末的平均浓度略低于工作日水平或与其持平。国庆假期,由于城区人口、车辆减少,长沙大气环境质量相对较好,而春节假期,由于受到烟花爆竹集中燃放的影响,PM₁₀、PM_2.5和SO₂浓度远超过全年平均水平,这在一定程度上说明人类活动对污染物浓度及大气环境质量变化具有一定的影响力。

Holiday Effects on Ambient Air Quality in Changsha During 2016

Based on the PM₁₀, PM_2.5, NO₂, O₃, CO and SO₂ concentrations in Changsha obtained from the continuous online monitoring system in 2016, the variation features of pollutants concentration and excellent days on weekdays, weekend and holiday especially Spring Festival were analyzed. It showed that there were weekend effects with six pollutants in Changsha. The average concentrations of the pollutants, especially PM_2.5, on weekend were lower than those of weekdays and annual average value. PM₁₀ and PM_2.5 concentrations are highest on Monday and lowest on Saturday. On weekend, the concentrations of CO and SO₂ remain lowest level, the average concentrations of NO₂ and O₃ were a little lower than or similar with those on weekdays. During National Day, the air quality in Changsha was very good due to the emission reduction from vehicles. However, PM₁₀, PM_2.5 and SO₂ concentrations were far above annual average level that ascribe to firecrackers during Spring Festival. It mainly occurred at midnight, dawn and dusk, which indicated that pollutants concentrations and air quality are effected by human activities to some extent.