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21st-century modeled permafrost carbon emissions accelerated by abrupt thaw beneath lakes.

https://arctichealth.org/en/permalink/ahliterature297387
Source
Nat Commun. 2018 08 15; 9(1):3262
Publication Type
Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Date
08-15-2018
Author
Katey Walter Anthony
Thomas Schneider von Deimling
Ingmar Nitze
Steve Frolking
Abraham Emond
Ronald Daanen
Peter Anthony
Prajna Lindgren
Benjamin Jones
Guido Grosse
Author Affiliation
Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA. kmwalteranthony@alaska.edu.
Source
Nat Commun. 2018 08 15; 9(1):3262
Date
08-15-2018
Language
English
Publication Type
Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Alaska
Carbon - chemistry
Carbon Cycle
Carbon Dioxide - chemistry
Conservation of Natural Resources - methods - trends
Freezing
Geography
Geologic Sediments - chemistry
Global warming
Lakes - chemistry
Methane - chemistry
Models, Theoretical
Permafrost - chemistry
Soil - chemistry
Abstract
Permafrost carbon feedback (PCF) modeling has focused on gradual thaw of near-surface permafrost leading to enhanced carbon dioxide and methane emissions that accelerate global climate warming. These state-of-the-art land models have yet to incorporate deeper, abrupt thaw in the PCF. Here we use model data, supported by field observations, radiocarbon dating, and remote sensing, to show that methane and carbon dioxide emissions from abrupt thaw beneath thermokarst lakes will more than double radiative forcing from circumpolar permafrost-soil carbon fluxes this century. Abrupt thaw lake emissions are similar under moderate and high representative concentration pathways (RCP4.5 and RCP8.5), but their relative contribution to the PCF is much larger under the moderate warming scenario. Abrupt thaw accelerates mobilization of deeply frozen, ancient carbon, increasing 14C-depleted permafrost soil carbon emissions by ~125-190% compared to gradual thaw alone. These findings demonstrate the need to incorporate abrupt thaw processes in earth system models for more comprehensive projection of the PCF this century.
PubMed ID
30111815 View in PubMed
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Aerobic biodegradation of vinyl chloride and cis-1,2-dichloroethylene in aquifer sediments.

https://arctichealth.org/en/permalink/ahliterature83353
Source
Chemosphere. 2005 Sep;60(11):1555-64
Publication Type
Article
Date
Sep-2005
Author
Broholm Kim
Ludvigsen Liselotte
Jensen Thorkild Feldthusen
Østergaard Henrik
Author Affiliation
DHI--Institute for Water and Environment, HSW, Agern Alle 5, DK-2970 Hørsholm, Denmark. kib@dhi.dk
Source
Chemosphere. 2005 Sep;60(11):1555-64
Date
Sep-2005
Language
English
Publication Type
Article
Keywords
Aerobiosis
Biodegradation, Environmental
Dichloroethylenes - chemistry
Geologic Sediments - chemistry
Methane - chemistry
Oxygen - chemistry
Vinyl Chloride - chemistry
Abstract
Laboratory batch experiments have been performed with sediment and groundwater obtained from two sites in Denmark to study the aerobic biodegradation of vinyl chloride (VC) and cis-1,2-dichloroethylene (c-1,2-DCE) to assess the natural aerobic biodegradation potential at two sites. The experiments revealed that VC was degraded to below the detection limit within 204 and 57 days at the two sites. c-1,2-DCE was also degraded in the experiments but not completely. At the two sites 50% and 35% was removed by the end of the experimental period of 204 and 274 days. The removal of c-1,2-DCE seems to occur concomitantly with VC indicating that the biodegradation of c-1,2-DCE may depend on the biodegradation of VC. However, in both cases natural groundwater was mixed with sediment and consequently there may be other compounds (e.g. ammonium, natural organic compound etc.) that serves as primary substrates for the co-metabolic biodegradation of c-1,2-DCE. At one of the sites methane was supplied to try to enhance the biodegradation of VC and c-1,2-DCE. That was successful since the time for complete biodegradation of VC decreased from 204 days in the absence of methane to 84 days in the presence of methane. For c-1,2-DCE the amount that was biodegraded after 204 days increased from 50% to 90% as a result of the addition of methane. It seems like a potential for natural biodegradation exists at least for VC at these two sites and also to some degree for c-1,2-DCE.
PubMed ID
16083761 View in PubMed
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Alder, Nitrogen, and Lake Ecology: Terrestrial-Aquatic Linkages in the Postglacial History of Lone Spruce Pond, Southwestern Alaska.

https://arctichealth.org/en/permalink/ahliterature284914
Source
PLoS One. 2017;12(1):e0169106
Publication Type
Article
Date
2017
Author
Bianca B Perren
Yarrow Axford
Darrell S Kaufman
Source
PLoS One. 2017;12(1):e0169106
Date
2017
Language
English
Publication Type
Article
Keywords
Alaska
Alnus - growth & development - metabolism
Animals
Biota
Climate
Climate change
Diatoms - physiology
Ecosystem
Geologic Sediments - chemistry
Lakes - chemistry
Nitrogen - metabolism
Picea - growth & development - metabolism
Ponds - chemistry
Soil
Abstract
Diatoms, combined with a multiproxy study of lake sediments (organic matter, N, d15N, d13C, biogenic silica, grain size, Cladocera and chironomids, Alnus pollen) from Lone Spruce Pond, Alaska detail the late-glacial to Holocene history of the lake and its response to regional climate and landscape change over the last 14.5 cal ka BP. We show that the immigration of alder (Alnus viridis) in the early Holocene marks the rise of available reactive nitrogen (Nr) in the lake as well as the establishment of a primarily planktonic diatom community. The later establishment of diatom Discostella stelligera is coupled to a rise of sedimentary d15N, indicating diminished competition for this nutrient. This terrestrial-aquatic linkage demonstrates how profoundly vegetation may affect soil geochemistry, lake development, and lake ecology over millennial timescales. Furthermore, the response of the diatom community to strengthened stratification and N levels in the past confirms the sensitivity of planktonic diatom communities to changing thermal and nutrient regimes. These past ecosystem dynamics serve as an analogue for the nature of threshold-type ecological responses to current climate change and atmospheric nitrogen (Nr) deposition, but also for the larger changes we should anticipate under future climate, pollution, and vegetation succession scenarios in high-latitude and high-elevation regions.
Notes
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PubMed ID
28076393 View in PubMed
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Anaerobic microbial Fe(II) oxidation and Fe(III) reduction in coastal marine sediments controlled by organic carbon content.

https://arctichealth.org/en/permalink/ahliterature285578
Source
Environ Microbiol. 2016 Sep;18(9):3159-74
Publication Type
Article
Date
Sep-2016
Author
Katja Laufer
James M Byrne
Clemens Glombitza
Caroline Schmidt
Bo Barker Jørgensen
Andreas Kappler
Source
Environ Microbiol. 2016 Sep;18(9):3159-74
Date
Sep-2016
Language
English
Publication Type
Article
Keywords
Anaerobiosis
Bacteria - classification - genetics - isolation & purification - metabolism
Carbon - analysis - metabolism
Denmark
Ferric Compounds - metabolism
Ferrous Compounds - metabolism
Geologic Sediments - chemistry - microbiology
Nitrates - metabolism
Oxidation-Reduction
Abstract
Coastal marine sediments contain varying concentrations of iron, oxygen, nitrate and organic carbon. It is unknown how organic carbon content influences the activity of nitrate-reducing and phototrophic Fe(II)-oxidizers and microbial Fe-redox cycling in such sediments. Therefore, microcosms were prepared with two coastal marine sediments (Kalø Vig and Norsminde Fjord at Aarhus Bay, Denmark) varying in TOC from 0.4 to 3.0 wt%. The microcosms were incubated under light/dark conditions with/without addition of nitrate and/or Fe(II). Although most probable number (MPN) counts of phototrophic Fe(II)-oxidizers were five times lower in the low-TOC sediment, phototrophic Fe(II) oxidation rates were higher compared with the high-TOC sediment. Fe(III)-amended microcosms showed that this lower net Fe(II) oxidation in the high-TOC sediment is caused by concurrent bacterial Fe(III) reduction. In contrast, MPN counts of nitrate-reducing Fe(II)-oxidizers and net rates of nitrate-reducing Fe(II) oxidation were comparable in low- and high-TOC sediments. However, the ratio of nitratereduced :iron(II)oxidized was higher in the high-TOC sediment, suggesting that a part of the nitrate was reduced by mixotrophic nitrate-reducing Fe(II)-oxidizers and chemoorganoheterotrophic nitrate-reducers. Our results demonstrate that dynamic microbial Fe cycling occurs in these sediments and that the extent of Fe cycling is dependent on organic carbon content.
PubMed ID
27234371 View in PubMed
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Anaerobic reductive dechlorination of 1,2,3,4-tetrachlorodibenzofuran in polychlorinated dibenzo-p-dioxin- and dibenzofuran-contaminated sediments of the Kymijoki River, Finland.

https://arctichealth.org/en/permalink/ahliterature258016
Source
Chemosphere. 2014 Mar;98:58-65
Publication Type
Article
Date
Mar-2014
Author
S. Kuokka
A-L Rantalainen
M M Häggblom
Author Affiliation
University of Helsinki, Dept. of Environmental Sciences, Lahti, Finland. Electronic address: sanna.kuokka@helsinki.fi.
Source
Chemosphere. 2014 Mar;98:58-65
Date
Mar-2014
Language
English
Publication Type
Article
Keywords
Anaerobiosis
Benzofurans - analysis - chemistry - metabolism
Biodegradation, Environmental
Finland
Geologic Sediments - chemistry - microbiology
Humans
Rivers - chemistry - microbiology
Tetrachlorodibenzodioxin - analogs & derivatives - analysis - chemistry - metabolism
Abstract
Sediments of the Kymijoki River are highly contaminated with polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). These persistent PCDD/Fs resist biotic degradation and therefore the potential for microbial reductive dechlorination was assessed to determine how microbes impact the fate of these compounds. Anaerobic sediment microcosms of five different sites in the river were spiked with 1,2,3,4-tetrachlorodibenzofuran (1,2,3,4-TeCDF) as a model compound to determine the dechlorination potential in the sediments. Dechlorinating bacteria were active in all the study sites of the river. The extent of dechlorination over 10 and 29 months corresponded to the levels of aged PCDD/Fs, with sediments of the most contaminated site at Kuusankoski being the most active for reductive dechlorination. The dechlorination activity and levels of aged PCDD/Fs were correlated within the sediment cores at the all sites. The pathway of 1,2,3,4-TeCDF dechlorination was mainly via 1,3,4-trichlorodibenzofuran (TrCDF) to 1,3-dichlorodibenzofuran (DiCDF). Dechlorination via 1,2,4-TrCDF to further dechlorination products was also detected. Lateral reductive dechlorination would decrease the toxicity of 2,3,7,8-substituted PCDD/Fs. Our data suggest that sediments of the Kymijoki River contain indigenous microorganisms that are responsible for dechlorination of PCDD/Fs, especially at the most contaminated site.
PubMed ID
24210554 View in PubMed
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Arctic antibiotic resistance gene contamination, a result of anthropogenic activities and natural origin.

https://arctichealth.org/en/permalink/ahliterature294570
Source
Sci Total Environ. 2018 Apr 15; 621:1176-1184
Publication Type
Journal Article
Date
Apr-15-2018
Author
Lu Tan
Linyun Li
Nicholas Ashbolt
Xiaolong Wang
Yuxiao Cui
Xiao Zhu
Yan Xu
Yang Yang
Daqing Mao
Yi Luo
Author Affiliation
Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, China.
Source
Sci Total Environ. 2018 Apr 15; 621:1176-1184
Date
Apr-15-2018
Language
English
Publication Type
Journal Article
Keywords
Anti-Bacterial Agents
Arctic Regions
China
Drug Resistance, Microbial - genetics
Genes, Bacterial
Geologic Sediments - chemistry
Human Activities
Humans
Phylogeny
RNA, Ribosomal, 16S - analysis
Abstract
The increasing global prevalence of antibiotic resistance genes (ARGs) in the environment is attributed to anthropogenic activities, particularly the misuse of antimicrobial drugs in human care and animal production. In the present study, we first examined Arctic/sub-Arctic (polar) sediments for the abundance and diversity of 30 ARGs against sulfonamide, tetracycline, aminoglycoside, quinolone, macrolide, and ß-lactam antibiotics. Polar sediment ARGs were detected by qPCR at relatively low levels (10-9 to 10-5 copies/16S rRNA gene copies) compared to the reference sites, which were heavily impacted regions of China (the Haihe River, the Tianjin Water Park water and the Qilihai Wetland water, at 10-8 to 10-2 copies/16S rRNA gene copies). A human mitochondrial gene target, Hmt, was first used to aid in the identification of ARGs associated with anthropogenic activities, being relatively persistent, in high copy number and a human-specific molecular marker. Hmt was consistently present in easily quantifiable amounts in the polar sediment samples, indicating their relationship with human-impact, and it was also positively correlated with the relative abundance of ARGs and to the concentrations of modern-day antibiotics. Phylogenetic analyses of resistance sequences from both the Arctic marine sediments and a major database of human pathogens indicated that the ARGs in polar region were the result of a mix of human influence and natural origins. To our knowledge, this is the first study to show that ARGs in Arctic marine sediments appear to be a mixture of both natural origins and recent human influence. This study provides a significant reference regarding the global reach of antibiotic resistance, which is associated with anthropogenic activities.
PubMed ID
29070451 View in PubMed
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Arctic hydrology during global warming at the Palaeocene/Eocene thermal maximum.

https://arctichealth.org/en/permalink/ahliterature95711
Source
Nature. 2006 Aug 10;442(7103):671-5
Publication Type
Article
Date
Aug-10-2006
Author
Pagani Mark
Pedentchouk Nikolai
Huber Matthew
Sluijs Appy
Schouten Stefan
Brinkhuis Henk
Damsté Jaap S Sinninghe
Dickens Gerald R
Author Affiliation
Department of Geology and Geophysics, Yale University, PO Box 208109, New Haven, Connecticut 06520, USA. mark.pagani@yale.edu
Source
Nature. 2006 Aug 10;442(7103):671-5
Date
Aug-10-2006
Language
English
Publication Type
Article
Keywords
Alkanes - metabolism
Arctic Regions
Biological Markers - analysis
Calcium Carbonate - analysis - metabolism
Carbon - metabolism
Carbon Isotopes
Geologic Sediments - chemistry
Greenhouse Effect
History, Ancient
Humidity
Hydrogen - analysis - chemistry
Marine Biology
Oceans and Seas
Plants - metabolism
Rain
Seawater - analysis - chemistry
Sodium Chloride - analysis
Temperature
Time Factors
Abstract
The Palaeocene/Eocene thermal maximum represents a period of rapid, extreme global warming 55 million years ago, superimposed on an already warm world. This warming is associated with a severe shoaling of the ocean calcite compensation depth and a >2.5 per mil negative carbon isotope excursion in marine and soil carbonates. Together these observations indicate a massive release of 13C-depleted carbon and greenhouse-gas-induced warming. Recently, sediments were recovered from the central Arctic Ocean, providing the first opportunity to evaluate the environmental response at the North Pole at this time. Here we present stable hydrogen and carbon isotope measurements of terrestrial-plant- and aquatic-derived n-alkanes that record changes in hydrology, including surface water salinity and precipitation, and the global carbon cycle. Hydrogen isotope records are interpreted as documenting decreased rainout during moisture transport from lower latitudes and increased moisture delivery to the Arctic at the onset of the Palaeocene/Eocene thermal maximum, consistent with predictions of poleward storm track migrations during global warming. The terrestrial-plant carbon isotope excursion (about -4.5 to -6 per mil) is substantially larger than those of marine carbonates. Previously, this offset was explained by the physiological response of plants to increases in surface humidity. But this mechanism is not an effective explanation in this wet Arctic setting, leading us to hypothesize that the true magnitude of the excursion--and associated carbon input--was greater than originally surmised. Greater carbon release and strong hydrological cycle feedbacks may help explain the maintenance of this unprecedented warmth.
Notes
Erratum In: Nature. 2006 Oct 5;443(7111):598
PubMed ID
16906647 View in PubMed
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Assessing PCB pollution in the Baltic Sea - An equilibrium partitioning based study.

https://arctichealth.org/en/permalink/ahliterature290670
Source
Chemosphere. 2018 Jan; 191:886-894
Publication Type
Journal Article
Date
Jan-2018
Author
Susann-Cathrin Lang
Philipp Mayer
Andrew Hursthouse
Danijela Kötke
Ines Hand
Detlef Schulz-Bull
Gesine Witt
Author Affiliation
University of Applied Sciences Hamburg, Department of Environmental Engineering, Ulmenliet 20, 21033 Hamburg, Germany; Institute of Biomedical and Environmental Health Research, School of Science & Sport, University of the West of Scotland, Paisley Campus, Paisley PA 1 2BE, United Kingdom. Electronic address: susann-cathrin.lang@agilent.com.
Source
Chemosphere. 2018 Jan; 191:886-894
Date
Jan-2018
Language
English
Publication Type
Journal Article
Keywords
Environmental Monitoring - methods
Environmental pollution - analysis
Finland
Gas Chromatography-Mass Spectrometry
Geologic Sediments - chemistry
Organic Chemicals - analysis
Polychlorinated biphenyls - analysis
Seawater - chemistry
Water Pollutants, Chemical - analysis
Abstract
Sediment cores and bottom water samples from across the Baltic Sea region were analyzed for freely dissolved concentrations (Cfree), total sediment concentrations (CT) and the dissolved aqueous fraction in water of seven indicator PCBs. Ex-situ equilibrium sampling of sediment samples was conducted with polydimethylsiloxane (PDMS) coated glass fibers that were analyzed by automated thermal desorption GC-MS, which yielded PCB concentrations in the fiber coating (CPDMS). Measurements of CPDMS and CT were then applied to determine (i) spatially resolved freely dissolved PCB concentrations; (ii) baseline toxicity potential based on chemical activities (a); (iii) site specific mixture compositions; (iv) diffusion gradients at the sediment water interface and within the sediment cores; and (vi) site specific distribution ratios (KD). The contamination levels were low in the Gulf of Finland and moderate to elevated in the Baltic Proper, with the highest levels observed in the western Baltic Sea. The SPME method has been demonstrated to be an appropriate and sensitive tool for area surveys presenting new opportunities to study the in-situ distribution and thermodynamics of hydrophobic organic chemicals at trace levels in marine environments.
PubMed ID
29107230 View in PubMed
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Assessment of the direct effects of biogenic and petrogenic activated carbon on benthic organisms.

https://arctichealth.org/en/permalink/ahliterature268307
Source
Environ Sci Technol. 2015 Mar 17;49(6):3705-10
Publication Type
Article
Date
Mar-17-2015
Author
Adam Lillicrap
Morten Schaanning
Ailbhe Macken
Source
Environ Sci Technol. 2015 Mar 17;49(6):3705-10
Date
Mar-17-2015
Language
English
Publication Type
Article
Keywords
Animals
Aquatic Organisms - drug effects
Charcoal - pharmacology
Crustacea - drug effects
Ecosystem
Geologic Sediments - chemistry
Norway
Petroleum
Toxicity Tests, Acute
Abstract
Activated carbon (AC) has long been associated with the capacity to effectively remove organic substances from aquatic and sediment matrices; however, its use in remediation purposes has drawn some concern due to possible impacts on benthic communities. Within the inner Oslofjord, the use of AC has been well documented for reducing the risks associated with dioxins or dioxin-like compounds from contaminated areas. However, benthic surveys performed on areas treated with AC have revealed that the abundance of organisms inhabiting these areas can be reduced significantly in the subsequent years following treatment. The reason for the reduction in the benthic communities is currently unknown, and therefore, an integrated approach to assess the effects of 2 different forms of AC (biogenic and petrogenic) on benthic organisms has been performed. A battery of 3 different benthic organisms with different feeding and life-cycle processes has been used encompassing sediment surface feeders, sediment ingestors, and sediment reworkers. Results of the tests indicated that although AC is not acutely toxic at concentrations up to 1000 mg/L, there may be physical effects of the substance on benthic dwelling organisms at environmentally relevant concentrations of AC at remediated sites.
PubMed ID
25723541 View in PubMed
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143 records – page 1 of 15.