广州市大气气态总汞含量季节和日变化特征

利用高时间分辨率自动测汞仪(tekran 2537B),于2010-11~2011-11对广州市大气气态总汞(TGM)进行了连续1a的观测.结果表明,广州市大气气态总汞的年平均含量为(4.86±1.36)ng/m3,表明该地区受到了一定程度的大气汞污染.TGM浓度按季节表现为:春季>冬季>秋季>夏季.TGM污染呈现春高夏低的现象,气象因素如边界层、静止风是影响其季节分布不同的主要原因.日变化趋势为中午最低,早晚出现2个高峰,边界层和温度对TGM日变化有很大影响.对广州市大气气态汞的可能来源分析结果表明,TGM主要来源于本地人为排放,其中市内燃煤电厂和水泥厂等人为源排放可能是广州市大气气态总汞的主要来源.

Seasonal and diurnal variation of total gaseous mercury in Guangzhou City

Total gaseous mercury(TGM) was continuously monitored using high-resolution automatic atmospheric mercury vapor analyzer(Tekran 2537B) from November 2010 to November 2011 in Guangzhou.The annual average TGM concentration was(4.86±1.36)ng/m3,suggesting that the atmosphere was polluted by mercury in this area.The TGM level exhibited distinct seasonal variation by the following order: spring>winter>autumn>summer.TGM pollution was more serious in winter but less in summer,which was caused by meteorological factors such as boundary layer,static wind.The diurnal variation showed that the minimum concentration was at noon and dual peaks appeared in the morning and evening,respectively.Boundary layer and temperature had significant impact on the diurnal variation.According to the source appointment of gaseous mercury in Guangzhou,local coal-fired power and cement plants may be the major contributors to the TGM in Guangzhou.