气候变化领域集成服务门户(CCPortal): Previously unaccounted atmospheric mercury deposition in a midlatitude deciduous forest

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DOI	10.1073/pnas.2105477118
	Previously unaccounted atmospheric mercury deposition in a midlatitude deciduous forest
	Obrist D.; Roy E.M.; Harrison J.L.; Kwong C.F.; William Munger J.; Moosmüller H.; Romero C.D.; Sun S.; Zhou J.; Commane R.
发表日期	2021
ISSN	0027-8424
卷号	118 期号:29
英文摘要	Mercury is toxic to wildlife and humans, and forests are thought to be a globally important sink for gaseous elemental mercury (GEM) deposition from the atmosphere. Yet there are currently no annual GEM deposition measurements over rural forests. Here we present measurements of ecosystem–atmosphere GEM exchange using tower-based micrometeorological methods in a midlatitude hardwood forest. We measured an annual GEM deposition of 25.1 μg · m−2 (95% CI: 23.2 to 26.7 1 μg · m−2), which is five times larger than wet deposition of mercury from the atmosphere. Our observed annual GEM deposition accounts for 76% of total atmospheric mercury deposition and also is three times greater than litterfall mercury deposition, which has previously been used as a proxy measure for GEM deposition in forests. Plant GEM uptake is the dominant driver for ecosystem GEM deposition based on seasonal and diel dynamics that show the forest GEM sink to be largest during active vegetation growing periods and middays, analogous to photosynthetic carbon dioxide assimilation. Soils and litter on the forest floor are additional GEM sinks throughout the year. Our study suggests that mercury loading to this forest was underestimated by a factor of about two and that global forests may constitute a much larger global GEM sink than currently proposed. The larger than anticipated forest GEM sink may explain the high mercury loads observed in soils across rural forests, which impair water quality and aquatic biota via watershed Hg export. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Dry deposition \| mass balance \| mercury cycling
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
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/238473
作者单位	Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts Lowell, Lowell, MA 01854, United States; Lamont–Doherty Earth Observatory, Columbia University, Palisades, NY 10964, United States; Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, United States; Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, United States; Division of Atmospheric Sciences, Desert Research Institute, Reno, NV 89512, United States; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, University of Chinese Academy of Sciences, Lanzhou, 730000, China
推荐引用方式 GB/T 7714	Obrist D.,Roy E.M.,Harrison J.L.,et al. Previously unaccounted atmospheric mercury deposition in a midlatitude deciduous forest[J]. 中国科学院西北生态环境资源研究院,2021,118(29).
APA	Obrist D..,Roy E.M..,Harrison J.L..,Kwong C.F..,William Munger J..,...&Commane R..(2021).Previously unaccounted atmospheric mercury deposition in a midlatitude deciduous forest.Proceedings of the National Academy of Sciences of the United States of America,118(29).
MLA	Obrist D.,et al."Previously unaccounted atmospheric mercury deposition in a midlatitude deciduous forest".Proceedings of the National Academy of Sciences of the United States of America 118.29(2021).