重庆大学城PM_(10)和PM_(2.5)污染分析与预测

Analysis and Prediction of PM_(10) and PM_(2.5) Pollution in Chongqing University Town

利用2015年1月—2016年12月重庆大学城空气质量国控点实时发布的颗粒物污染监测数据,对PM_(10)和PM_(2.5)达标情况、两者之间的相关性以及影响因素进行了分析,并预测了未来的变化。结果表明:重庆大学城PM_(10)日均质量浓度为0.006~0.283 mg/m^3,均值为0.075 mg/m^3,超标率为4.7%;PM_(2.5)日均质量浓度为0.005~0.193 mg/m^3,均值为0.052 mg/m^3,超标率为15.4%。两者存在明显的正相关性(R=0.955 9~0.987 9),全年β值(ρ(PM_(2.5))/ρ(PM_(10)))为0.333~0.940,均值为0.697。高β值和降雨对PM_(2.5)清除显著说明:重庆大学城PM_(2.5)二次污染所占比重较大,且PM_(2.5)的前体物为易被降雨清除的物质。2016年重庆大学城PM_(10)和PM_(2.5)日均质量浓度均值较2015年分别下降8.9%,5.6%,预计未来PM_(10)和PM_(2.5)日均质量浓度降幅将变小甚至出现增加现象,而重污染天数将减少且程度也会减轻。

The demonstrating compliance,relativity and influence factors of PM_(10) and PM_(2.5) from Chongqing University Town national control sites were analyzed by utilizing real-time date from January of 2015 to December of 2016,and their future mass concentration changes were predicted.The results shows that daily mass concentrations of PM_(10) varied between 0.006 mg/m^3and 0.283mg/m^3with the average value of 0.075 mg/m^3and the over standard rate of 4.7%;and the above data of PM_(2.5) were 0.005 mg/m^3and0.193 mg/m^3,0.052 mg/m^3,15.4%,respectively.Daily mass concentrations of PM_(10) and PM_(2.5) varied similarly and were significantly positive correlated(R=0.955 9~0.987 9),the rate ofρ(PM_(2.5) )/ρ(PM_(10) )(also calledβ)ranged from 0.333 to 0.940 with the average value was 0.697.The high value ofβand PM_(2.5) was removed by rainfall significantly,indicating that PM_(2.5) had a higher proportion of secondary pollution,and the precursors of PM_(2.5) were easily removed by rainfall.In 2016,the average of daily mass concentrations of PM_(10) and PM_(2.5) in Chongqing University Town were 8.9%,which was 5.6%lower than that in the year of 2015.It is expected that in the future the decline range of daily mass concentrations of PM_(10) and PM_(2.5) in Chongqing University Town will be reduced and even the mass concentrations of PM_(10) and PM_(2.5) will be increased,but the days of heavy pollution will be decreased and the degree of extreme pollution will be reduced.