摘要
于2017年10月~2018年9月,在青岛胶州湾沿岸城区连续采集了10个月的降水样品,测定了其不同形态汞的浓度,并计算其湿沉降量。结果表明,降水中总汞(THg)、溶解态总汞(DTHg)、颗粒态总汞(PTHg)、总甲基汞(TMeHg)、溶解态甲基汞(DMeHg)和颗粒态甲基汞(PMeHg)的年体积加权平均浓度(VWM)分别为5.7、3.6、2.1、0.22、0.16和0.06 ng·L^-1;年沉降量分别为3145.4、1975.9、1169.5、118.91、86.63和32.28 ng·m^-2。THg浓度与降水量之间呈显著负相关,不同形态汞的湿沉降量与降雨量之间呈显著正相关,说明降水量是影响THg浓度及不同形态汞湿沉降的重要因素。此外,降水中THg浓度还受大气中的PM 2.5、PM 10、NO2浓度和降水pH等反映人为活动的因子的影响,表明人类活动也显著干扰青岛胶州湾沿岸地区降水中汞的浓度。HYSPLIT模型后向轨迹分析结果表明冬季降水中高浓度的汞主要来自于北方和青岛当地的燃煤取暖,而夏季降水中高浓度的甲基汞以及较高的TMeHg/THg比例主要是因为来源于海洋的气团携带了较高浓度的甲基汞,说明海源可能也是青岛胶州湾沿岸城区降水中甲基汞的一个重要来源。
Precipitation samples were collected from October 2017 to September 2018 in the urban areas of Qingdao(adjacent to the Jiaozhou Bay)to determine the concentrations of different species of mercury(Hg)and calculate their wet deposition fluxes.The results showed that annual volume-weighted mean(VWM)concentrations of total Hg(THg),dissolved THg(DTHg),particulate THg(PTHg),total methylmercury(TMeHg),dissolved MeHg(DMeHg),and particulate methylmercury(PMeHg)were 5.7,3.6,2.1,0.22,0.16,and 0.06 ng·L^-1,separately.The annual deposition fluxes were estimated to be 3145.4 ng·m^-2 for THg,1975.9 ng·m^-2 for DTHg,1169.5 ng·m^-2 for PTHg,118.91 ng·m^-2 for TMeHg,86.63 ng·m^-2 for DMeHg,and 32.28 ng·m^-2 for PMeHg,respectively.The significant negative correlation between THg concentration and precipitation,and the significant positive correlation between the wet deposition of various Hg species and precipitation,indicated that rainfall may be an important factor for THg concentrations and wet deposition of Hg in Qingdao.In addition,the THg concentration in precipitation also showed a good correlation with PM 2.5,PM 10,NO2 and pH in the atmosphere,suggesting that human activities may have significant effects on the concentrations of Hg in the precipitation in the coastal urban areas of Qingdao.The results of 72 h backward trajectory conducted by HYSPLIT model showed that the atmospheric Hg in winter mainly originates from the northern and local sources where coal burning is the dominant heating way.The high concentration of methylmercury in summer precipitation could be due to the higher concentration of methylmercury carried by marine air masses,and suggested that marine source may also be an important source of methylmercury in precipitation in coastal urban area of Qingdao Jiaozhou Bay.
作者
李颖
邵主峰
陈路锋
韩秀荣
李雁宾
LI Ying;SHAO Zhu-Feng;CHEN Lu-Feng;HAN Xiu-Rong;LI Yan-Bin(The Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingda O266100,China;Institute of Environment and Health,Jianghan University,Wuhan 430056,China;College of Chemistry and Chemical Engineering,Ocean University of China,Qingda O266100,China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第5期104-115,共12页
Periodical of Ocean University of China
基金
中央高校基本科研业务费专项项目(201762031,201841008)
国家自然科学基金项目(21577134)资助。
关键词
汞
形态
湿沉降
沉降量
青岛
mercury
species
precipitation
deposition flux
Qingdao
