贵阳市2001/2002和2009/2010两个年度大气气态总汞浓度变化特征及其对区域大气汞排放强度的指示意义

Variations of Atmospheric Total Gaseous Mercury Concentrations for the Sampling Campaigns of 2001 /2002 and 2009 /2010 and Implications of Changes in Regional Emissions of Atmospheric Mercury

本研究对贵阳市2001/12-2002/11和2009/12-2010/11两个年度大气气态总汞分别进行了为期1年的连续观测。结果显示,贵阳市大气气态总汞几何平均值由2001/2002年度的7.45±12.80ng/m^3升高到2009/2010年度的8.88±7.06ng/m^3,升高幅度为19%。2009/2010年度大气气态总汞（TGM）浓度的升高主要出现在冬季、秋季和春季,而其夏季的TGM浓度和2001/2002年度基本相当。另外,2009/2010年度白天TGM浓度较2001/2002年度的升高幅度（33%）明显大于夜间（7%）。贵阳市TGM升高的现象与贵阳市和贵州省人为源汞释放量增强的趋势是一致的,说明区域人为源汞释放的增加是贵阳市大气汞含量升高的首要原因。此外,中国内陆和中南半岛人为源汞释放强度的增强可能也是不可忽视的原因。

The long-term measurement of atmospheric mercury is an important indicator for understanding the temporal variation of regional Hg emissions. We carried out two one-year-long continuous measurements of the atmospheric total gaseous mercury （TGM） in Guiyang in the campaigns of 2001/2002 and 2009/2010. The geometric mean of TGM concentrations in Guiyang increased from 7.45±12.80 ng/m^3 in 2001/2002 to 8.88±7.06 ng/m^3 in 2009/2010, showing an increasing rate of 19%. The increasing of atmospheric TGM concentrations mainly occurred in winter, autumn, and spring, whereas the levels of TGM in summer for the two campaigns were consistent. Also, the increasing rate of atmospheric TGM from 2009/2010 to 2001/2002 was much higher during day-time （33%） than during night-time （7%）. The increasing trend of atmospheric TGM in Guiyang agrees well with the anthropogenie mercury emissions in Guiyang as well as in the Guizhou province, indicating the increasing of regional anthropogenic mercury emissions played an important role. In addi- tion, impact of increasing emissions of atmospheric mercury in the mainland of China and the Indo-China Peninsula, which may contribute to the increasing TGM via long-range atmospheric transports, cannot be ruled out.