Anthropogenic and natural drivers of seesaw-like spatial patterns in precipitation mercury over western China. (15th August 2022)

• Record Type: Journal Article
• Authors: Huang, Jie; Kang, Shichang; Wang, Long; Liu, Kaiyun; Ram, Kirpa; Sillanpää, Mika; Tang, Wenjun; Guo, Junming; Zhang, Qianggong; Ma, Ming; Tripathee, Lekhendra; Wang, Feiyue
• Is Part Of: Environmental pollution. Volume 307(2022)
• Publication Date: 2022-08-15
• Subjects: Precipitation mercury -- Seesaw-like patterns -- Anthropogenic and natural drivers -- Western China; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2022.119525
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Investigation of mercury (Hg) from atmospheric precipitation is important for evaluating its ecological impacts and developing mitigation strategies. Western China, which includes the Tibetan Plateau and the Xinjiang Uyghur Autonomous Region, is one of the most remote region in the world and is understudied in regards to Hg precipitation. Here we report seesaw-like patterns in spatial variations of precipitation Hg in Western China, based on Hg speciation measurements at nine stations over this remote region. The Hg fraction analyzed included total Hg (HgT ), particulate-bound Hg (HgP ) and methylmercury (MeHg). Spatially, HgT concentrations and percentage of HgP in precipitation were markedly greater in the westerlies domain than those in the monsoon domain, but the higher wet HgT flux, MeHg concentration and percentage of MeHg in precipitation mainly occurred in the monsoon domain. Similar spatial patterns of wet Hg deposition were also obtained from GEOS-Chem modeling. We show that the disparity of anthropogenic and natural drivers between the two domains are mainly responsible for this seesaw-like spatial patterns of precipitation Hg in Western China. Our study may provide a baseline for assessment of environmental Hg pollution in Western China, and subsequently assist in protecting this remote alpine ecosystem. Graphical abstract: Image 1 Highlights: We found a distinct seesaw-like pattern in spatial variation of precipitation Hg. Precipitation Hg varies significantly between the westerlies and monsoon domains. GEOS-Chem modeling captures similar seesaw-like patterns of wet Hg deposition. Abstract : A distinct seesaw-like pattern in spatial variation of precipitation Hg was first revealed over Western China.