Characterizations of wet mercury deposition on a remote high-elevation site in the southeastern Tibetan Plateau.
Accurate measurements of wet mercury (Hg) deposition are critically important for the assessment of ecological responses to pollutant loading. The Hg in wet deposition was measured over a 3-year period in the southeastern Tibetan Plateau. The volume-weighted mean (VWM) total Hg (HgT) concentration was somewhat lower than those reported in other regions of the Tibetan Plateau, but the VWM methyl-Hg concentration and deposition flux were among the highest globally reported values. The VWM HgT concentration was higher in non-monsoon season than in monsoon season, and wet HgT deposition was dominated by the precipitation amount rather than the scavenging of atmospheric Hg by precipitation. The dominant Hg species in precipitation was mainly in the form of dissolved Hg, which indicates the pivotal role of reactive gaseous Hg within-cloud scavenging to wet Hg deposition. Moreover, an increasing trend in precipitation Hg concentrations was synchronous with the recent economic development in South Asia.
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, Mikkeli FI-50130, Finland.
Jie
J
Huang
State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: shichang.kang@lzb.ac.cn.
Shichang
S
Kang
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China.
Qianggong
Q
Zhang
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
Junming
J
Guo
Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, Mikkeli FI-50130, Finland.
Mika
M
Sillanpää
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.
Yongjie
Y
Wang
State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
Shiwei
S
Sun
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
Xuejun
X
Sun
Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China.
Lekhendra
L
Tripathee
D000393:Air Pollutants / Q000032:analysis*; D000531:Altitude; D001208:Asia; D004784:Environmental Monitoring / Q000379:methods*; D005740:Gases; D008628:Mercury / Q000032:analysis*; D011891:Rain; D012621:Seasons; D018609:Tibet
D000393:Air Pollutants; D005740:Gases; D008628:Mercury
Long-term variation; Mercury speciation; Southeastern Tibetan Plateau; Wet deposition