重庆市主城区大气汞调查研究

Investigation of Atmospheric Mercury in the Main Urban Area of Chongqing

利用Lumex RA-915^＋汞分析仪，对重庆主城区大气汞浓度进行了系统的调查监测．结果显示，重庆主城区大气汞浓度范围为0．10-86．82ng／m^3，均值6．45±0．03ng／m^3，高于全球背景水平．重庆主城区大气汞具有一定的空间分布特征和明显的时间变化特征．交通区，工业区和商业区大气汞浓度分别为7．07，7．05和6．71ng／m^3，差异性不显著，但明显高于文教区（5．97ng／m^3）和自然保护区（4．65ng／m^3）．不同功能区大气汞浓度月变化特征基本一致，从8月到11月大气汞浓度逐月升高，11月达到峰值，而后急剧下降，并趋于相对稳定．在缙云山，大气汞浓度白天明显高于夜间，而西南大学和重庆火力发电厂大气汞日变化特征与之刚好相反，说明大气汞浓度的日变化特征受地区空气污染状况的影响．重庆主城区大气汞浓度与光照强度呈极显著的负相关，与相对湿度呈极显著的正相关，与气温和气压的相关性不显著．

The concentration of atmospheric mercury in the main urban area of Chongqing was measured using the Lumex RA-915% mercury analyzer. The concentrations of atmospheric mercury during the study period ranged from 0.10 to 86.82 ng/ma , averaging 6.45±0.03 ng/ma , which was much higher than the accepted global background concentration. The atmospheric mercury concentrations in Chongqing were greatly influenced by the land-use and the ambient environment. The atmospheric mercury concentrations were 7.07, 7.05 and 6.71 ng/m^3 in the transport, industrial and commercial areas, respectively, which were non-significantly different from each other, but were significantly higher than in the educational （5.97 ng/ma） and natural conservation areas （4.65 ng/m^3 ）. The atmospheric mercury showed monthly and diurnal variation during the study period. In all the function areas, it gradually increased from Aug. to Nov. , reached the peak values in Nov. , dropped sharply thereafter and then became gradually stabilized. The characteristics of diurnal patterns of atmospheric mercury were influenced by the ambient environ- ment. The atmospheric mercury concentrations in the Jinyun Mountains were distinctly higher during the day than at night, which was contrary to the situation at the two sites of Southwest University and Chongqing Power Plant. The concentrations of atmospheric mercury were in a highly significant negative correlation with solar radiation, in a highly significant positive correlation with atmospheric relative humidity and in a non-significant correlation with air temperature or atmospheric pressure.