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Atmospheric HCH concentrations over the Marine Boundary Layer from Shanghai, China to the Arctic Ocean: role of human activity and climate change.

https://arctichealth.org/en/permalink/ahliterature100196
Source
Environ Sci Technol. 2010 Nov 15;44(22):8422-8
Publication Type
Article
Date
Nov-15-2010
Author
Xiaoguo Wu
James C W Lam
Chonghuan Xia
Hui Kang
Liguang Sun
Zhouqing Xie
Paul K S Lam
Author Affiliation
Institute of Polar Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
Source
Environ Sci Technol. 2010 Nov 15;44(22):8422-8
Date
Nov-15-2010
Language
English
Publication Type
Article
Abstract
From July to September 2008, air samples were collected aboard the research expedition icebreaker XueLong (Snow Dragon) as part of the 2008 Chinese Arctic Research Expedition Program. Hexachlorocyclohexane (HCH) concentrations were analyzed in all of the samples. The average concentrations (? standard deviation) over the entire period were 33 ? 16, 5.4 ? 3.0, and 13 ? 7.5 pg m?? for a-, ?- and ?-HCH, respectively. Compared to previous studies in the same areas, total HCH (SHCH, the sum of a-, ?-, and ?-HCH) levels declined by more than 10 ? compared to those observed in the 1990s, but were approximately 4 ? higher than those measured by the 2003 China Arctic Research Expedition, suggesting the increase of atmospheric SHCH recently. Because of the continuing use of lindane, ratios of a/?-HCH showed an obvious decrease in North Pacific and Arctic region compared with those for 2003 Chinese Arctic Research Expedition. In Arctic, the level of a-HCH was found to be linked to sea ice distribution. Geographically, the average concentration of a-HCH in air samples from the Chukchi and Beaufort Seas, neither of which contain sea ice, was 23 ? 4.4 pg m??, while samples from the area covered by seasonal ice (~75?N to ~83?N), the so-called "floating sea ice region", contained the highest average levels of a-HCH at 48 ? 12 pg m??, likely due to emission from sea ice and strong air-sea exchange. The lowest concentrations of a-HCH were observed in the pack ice region in the high Arctic covered by multiyear sea ice (~83?N to ~86?N). This phenomenon implies that the re-emission of HCH trapped in ice sheets and Arctic Ocean may accelerate during the summer as ice coverage in the Arctic Ocean decreases in response to global climate change.
PubMed ID
20977270 View in PubMed
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d(13)C-CH4 reveals CH4 variations over oceans from mid-latitudes to the Arctic.

https://arctichealth.org/en/permalink/ahliterature265870
Source
Sci Rep. 2015;5:13760
Publication Type
Article
Date
2015
Author
Juan Yu
Zhouqing Xie
Liguang Sun
Hui Kang
Pengzhen He
Guangxi Xing
Source
Sci Rep. 2015;5:13760
Date
2015
Language
English
Publication Type
Article
Abstract
The biogeochemical cycles of CH4 over oceans are poorly understood, especially over the Arctic Ocean. Here we report atmospheric CH4 levels together with d(13)C-CH4 from offshore China (31°N) to the central Arctic Ocean (up to 87°N) from July to September 2012. CH4 concentrations and d(13)C-CH4 displayed temporal and spatial variation ranging from 1.65 to 2.63 ppm, and from -50.34% to -44.94% (mean value: -48.55?±?0.84%), respectively. Changes in CH4 with latitude were linked to the decreasing input of enriched d(13)C and chemical oxidation by both OH and Cl radicals as indicated by variation of d(13)C. There were complex mixing sources outside and inside the Arctic Ocean. A keeling plot showed the dominant influence by hydrate gas in the Nordic Sea region, while the long range transport of wetland emissions were one of potentially important sources in the central Arctic Ocean. Experiments comparing sunlight and darkness indicate that microbes may also play an important role in regional variations.
PubMed ID
26323236 View in PubMed
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Historical records and contamination assessment of potential toxic elements (PTEs) over the past 100 years in Ny-Ă…lesund, Svalbard.

https://arctichealth.org/en/permalink/ahliterature305231
Source
Environ Pollut. 2020 Nov; 266(Pt 1):115205
Publication Type
Journal Article
Date
Nov-2020
Author
Zhongkang Yang
Linxi Yuan
Zhouqing Xie
Jun Wang
Zhaolei Li
Luyao Tu
Liguang Sun
Author Affiliation
Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, 230026, China; College of Resources and Environment, Key Laboratory of Agricultural Environment in Universities of Shandong, Shandong Agricultural University, Tai'an, 271000, China.
Source
Environ Pollut. 2020 Nov; 266(Pt 1):115205
Date
Nov-2020
Language
English
Publication Type
Journal Article
Keywords
Environmental monitoring
Metals, Heavy - analysis
Risk assessment
Soil
Soil Pollutants - analysis
Svalbard
Abstract
Ny-Ålesund has been significantly impacted by anthropogenic activities (e.g. coal mining, scientific research, tourist shipping) over the past 100 years. However, the studies of potential toxic elements (PTEs) contamination in Ny-Ålesund currently mainly focus on surface soil or surface fjord sediments, and little is known about the history and status of PTEs contamination over the past 100 years. In this study, we collected a palaeo-notch sediment profile YN, analyzed the contents of six typical PTEs (Cu, Pb, Cd, Hg, As, Se) in the sediments, and assessed the historical pollution status in Ny-Ålesund using the pollution load index, geo-accumulation index and enrichment factor. The results showed that the contents of PTEs over the past 100 years increased rapidly compared with those during the interval of 9400-100 BP. In addition, Pb, Cd and Hg showed a clear signal of enrichment and were the main polluters among the PTEs analyzed. The contamination was likely linked to gas-oil powered generators, coal mining, research station, tourist shipping and long-range transport of pollutants.
PubMed ID
32707354 View in PubMed
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Sterols and stanols preserved in pond sediments track seabird biovectors in a High Arctic environment.

https://arctichealth.org/en/permalink/ahliterature274326
Source
Environ Sci Technol. 2016 Jul 13;
Publication Type
Article
Date
Jul-13-2016
Author
Wenhan Cheng
Liguang Sun
Linda E Kimpe
Mark L Mallory
John P Smol
Lauren R Gallant
Jinping Li
Jules M Blais
Source
Environ Sci Technol. 2016 Jul 13;
Date
Jul-13-2016
Language
English
Publication Type
Article
Abstract
Seabirds are major vertebrates in the coastal ecosystems of the Canadian High Arctic, where they transport substantial amounts of marine-derived nutrients and pollutants from oceans to land by depositing guano and stomach oils to their nesting area, which often includes nearby freshwater ponds. Here we present novel indicators for evaluating the impact of seabirds on freshwater ecosystems. The ratio of cholesterol : (cholesterol + sitosterol) in pond sediments showed significant enrichment near a nesting colony of northern fulmars (Fulmarus glacialis) and was significantly correlated with ornithogenic enrichment of sediment as determined by sedimentary d15N. The sterol ratio was also correlated with several bioaccumulative persistent organic pollutants (POPs), suggesting its usefulness in tracking biovector enrichment of contaminants. Human-derived epicoprostanol was also analyzed in the sediments, and its relationship with an abandoned, prehistoric settlement was recorded, suggesting its potential as a tracer of prehistoric human activities in the Arctic. Sterols and stanols preserved in sediments appear to be useful geochemical tools that will inform our understanding of migratory species and the presence of pre-historic human populations in the Arctic, and possibly other animal populations.
PubMed ID
27409713 View in PubMed
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