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DOI	10.1016/j.scitotenv.2018.11.338
	Spatial and temporal distribution of total mercury in atmospheric wet precipitation at four sites from the Nepal-Himalayas
	Tripathee, Lekhendra; Guo, Junming; Kang, Shichang; Paudyal, Rukumesh; Huang, Jie; Sharma, Chhatra Mani; Zhang, Qianggong; Chen, Pengfei; Ghimire, Prakriti Sharma; Sigdel, Madan
发表日期	2019
ISSN	0048-9697
EISSN	1879-1026
卷号	655
英文摘要	The studies on global pollutant mercury (Hg), which is of public concern due to its high toxicity and capacity to long-range transport via atmospheric circulation, is poorly characterized in wet deposition over the Nepal-Himalayas region. Therefore, in order to understand the concentration levels, spatial distribution and seasonal variation of total Hg, 333 precipitation samples were collected from south to north: Kathmandu (1314 m a.s.l.), Dhunche (2065 m a.s.l.), Dimsa (3078 m a.s.l.) and Gosainkunda (4417 m a.s.l.) characterized as urban, rural, remote forest and remote alpine sites, respectively, for over one-year period. The highest Hg concentration was found in Kathmandu comparable to the urban sites worldwide, and significantly lower concentrations at other three sites demonstrated similar levels as in rural and remote alpine sites worldwide. Higher wet deposition fluxes of 34.91 and 15.89 mu gm(-2) year(-1) were found in Kathmandu and Dhunche respectively, due to higher precipitation amount. Clear and distinct seasonal differences were observed with higher concentrations in non-monsoon and lower values in monsoon periods due to less scavenging and high pollutant concentration loadings during the dry period. The positive correlation of Hg flux and precipitation amount with Hg concentration suggested that both precipitation amount and Hg concentration plays a vital role in Hg deposition in the central Himalayan region. Enrichment factor (EFHg) indicated that the anthropogenic emission sources play a significant role for Hg enrichment and a high ratio of EFmonsoon to EFnon-monsoon (>2.18) suggested that the anthropogenic atmospheric mercury could likely be long-range transported from south Asian regions to the Himalayas during the monsoon season. In addition, our results showed that the major ionic compositions (e.g., SO42-, NO3-, NH4+, K+, Ca2+) could influence Hg concentration in wet precipitation. The anthropogenic sources of Hg such as bio-mass and fossil fuel combustion, crustal aerosols may contribute to the Hg concentration in wet precipitation over the central Himalayas. (C) 2018 Elsevier B.V. All rights reserved.
关键词	Mercury Wet deposition Spatial distribution Central Himalayas South Asia
学科领域	Environmental Sciences & Ecology
语种	英语
WOS研究方向	Environmental Sciences
来源期刊	SCIENCE OF THE TOTAL ENVIRONMENT
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/112035
作者单位	Chinese Acad Sci, State Key Lab Cryospher Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Gansu, Peoples R China
推荐引用方式 GB/T 7714	Tripathee, Lekhendra,Guo, Junming,Kang, Shichang,et al. Spatial and temporal distribution of total mercury in atmospheric wet precipitation at four sites from the Nepal-Himalayas[J]. 中国科学院西北生态环境资源研究院,2019,655.
APA	Tripathee, Lekhendra.,Guo, Junming.,Kang, Shichang.,Paudyal, Rukumesh.,Huang, Jie.,...&Sigdel, Madan.(2019).Spatial and temporal distribution of total mercury in atmospheric wet precipitation at four sites from the Nepal-Himalayas.SCIENCE OF THE TOTAL ENVIRONMENT,655.
MLA	Tripathee, Lekhendra,et al."Spatial and temporal distribution of total mercury in atmospheric wet precipitation at four sites from the Nepal-Himalayas".SCIENCE OF THE TOTAL ENVIRONMENT 655(2019).