scholarly journals Signatures of Molecular Unification and Progressive Oxidation Unfold in Dissolved Organic Matter of the Ob-Irtysh River System along Its Path to the Arctic Ocean

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
I. V. Perminova ◽  
E. A. Shirshin ◽  
A. Zherebker ◽  
I. I. Pipko ◽  
S. P. Pugach ◽  
...  
Keyword(s):  
Organic Matter ◽  
High Resolution Mass Spectrometry ◽  
Solid Phase ◽  
River System ◽  
Low Flow ◽  
The Arctic ◽  
The South ◽  
Molecular Features ◽  
The World ◽  
Irtysh River

AbstractThe Ob-Irtysh River system is the seventh-longest one in the world. Unlike the other Great Siberian rivers, it is only slightly impacted by the continuous permafrost in its low flow. Instead, it drains the Great Vasyugan mire, which is the world largest swamp, and receives huge load of the Irtysh waters which drain the populated lowlands of the East Siberian Plain. The central challenge of this paper is to understand the processes responsible for molecular transformations of natural organic matter (NOM) in the Ob-Irtysh river system along the South-North transect. For solving this task, the NOM was isolated from the water samples collected along the 3,000 km transect using solid-phase extraction. The NOM samples were further analyzed using high resolution mass spectrometry and optical spectroscopy. The obtained results have shown a distinct trend both in molecular composition and diversity of the NOM along the South-North transect: the largest diversity was observed in the Southern “swamp-wetland” stations. The samples were dominated with humic and lignin-like components, and enriched with aminosugars. After the Irtysh confluence, the molecular nature of NOM has changed drastically: it became much more oxidized and enriched with heterocyclic N-containing compounds. These molecular features are very different from the aliphatics-rich permafrost NOM. They witnesses much more conservative nature of the NOM discharged into the Arctic by the Ob-Irtysh river system. In general, drastic reduction in molecular diversity was observed in the northern stations located in the lower Ob flow.

scholarly journals Petrographical and Geochemical Signatures Linked to Fe/Mn Reduction in Subsurface Marine Sediments from the Hydrate-Bearing Area, Dongsha, the South China Sea

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 624 ◽  
Author(s):  
Xi Xiao ◽  
Qian-Zhi Zhou ◽  
Shao-Ying Fu ◽  
Qian-Yong Liang ◽  
Xiang-Po Xu ◽  
...  
Keyword(s):  
Organic Matter ◽  
South China Sea ◽  
Marine Sediments ◽  
South China ◽  
Inorganic Carbon ◽  
Solid Phase ◽  
The South China Sea ◽  
Anaerobic Oxidation Of Methane ◽  
The South ◽  
China Sea

Fe and Mn oxides and (oxy)-hydroxides are the most abundant solid-phase electron acceptors in marine sediments, and dissimilatory Fe/Mn reduction usually links with the anaerobic oxidation of methane (AOM) and organic matter oxidation (OMO) in sediments. In this study, we report the results from subsurface marine sediments in the Dongsha hydrate-bearing area in the South China Sea. The petrological and geochemical signatures show that the Fe/Mn reduction mediated by AOM and OMO might occur in sediments above the sulfate-methane transition zone. X-ray diffraction and scanning electron microscopy analyses of sediments indicate that Fe(III)/Mn(IV)-oxides and authigenic carbonate minerals coexisted in the Fe/Mn reduction zone. The lower δ13C values of dissolved inorganic carbon, coupled with an evident increase in total inorganic carbon contents and a decrease in Ca2+ and Mg2+ concentrations indicate the onset of AOM in this zone, and the greater variation of PO43− and NH4+ concentrations in pore water suggests the higher OMO rates in subsurface sediments. Geochemical and mineralogical analyses suggest that the previously buried Fe(III)/Mn(IV) oxides might be activated and lead to the onset of Fe/Mn reduction induced by AOM and OMO. These findings may extend our understanding of the biogeochemical processes involved in Fe/Mn reduction in continental shelves with abundant methane, organic matter, and terrigenous metal oxides.

‘Take it from the top’: northern conceptions about identity in the western Arctic and beyond

Polar Record ◽  
2012 ◽  
Vol 48 (3) ◽  
pp. 222-229 ◽  
Author(s):  
Suzanne Robinson
Keyword(s):  
Northwest Territories ◽  
The Arctic ◽  
The South ◽  
Research Project ◽  
The North ◽  
The World ◽  
Western Arctic ◽  
Student Researchers

ABSTRACTDuring the last decades the Arctic has become more central on the world stage. However, despite increased interest how much do people really know about ‘the north’ and the ‘northern people’? The aim of this article is to chronicle a research project by students, who saw themselves as northerners, that used video to capture northerners’ definitions of the north, as well as asking the community about what they wanted newcomers and southern Canada to know about the north. The group also embarked on a new discipline of northerners studying ‘the south’. 43 students interviewed 95 people in the Beaufort Delta, Northwest Territories and 25 people in Edmonton, Alberta. The student researchers’ responses and that of their interviewees are some of the most direct messages on how northerners view their identity and that of their fellow southern Canadians. This project created a video tool to share, educate, and commence a dialogue between people about the north straight from the source.

scholarly journals Jusshjelpa i Nord Norge – a Legal Advice Clinic in Northern Norway

2014 ◽  
Vol 7 ◽  
pp. 44
Author(s):  
Lancelot Robson ◽  
Christian Hanssen
Keyword(s):  
Law Students ◽  
The Arctic ◽  
The South ◽  
Arctic Circle ◽  
Northern Norway ◽  
Legal Advice ◽  
The World ◽  
Student Volunteers ◽  
The Law

<p>The area covered by the Clinic must be one of the largest and most remote in the world. It covers the whole of northern Norway from Bodo in the south to Kirkenes near the Russian border, and includes the “counties” of Nordland, Troms and Finnmark. All of it lies within the Arctic Circle, which brings special challenges from the climate and thinly spread population. The permanent base is in Tromso, in offices behind the port loaned from Tromso University. From there student volunteers travel to visit most communes in the area, including Norwegian Lapland. Volunteers attempt to visit clients in each major commune at least twice a year, (cases came from 78 communes in 2003), either upon request, or by advertising a clinic session in the local commune building. Sessions in 28 major communes outside Tromso were held in 2003.</p><p><br />The clinic is one of five similar clinics covering the whole of Norway, all founded upon operational and management principles pioneered by law students at Oslo University in the early 1970s. The Oslo JussBuss (literally the “law bus”) has passed into Norwegian legal legend.</p>

scholarly journals Implications of sample treatment on characterization of the riverine environmental metabolome

2021 ◽  
Author(s):  
Amelia R Nelson ◽  
Jason Toyoda ◽  
Rosalie K Chu ◽  
Nikola Tolic ◽  
Vanessa Garayburu-Caruso ◽  
...  
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
High Resolution Mass Spectrometry ◽  
Solid Phase ◽  
Sample Treatment ◽  
East River ◽  
Ionization Mode ◽  
Single Method ◽  
Pre Treatment

High-resolution mass spectrometry techniques are widely used in the environmental sciences to characterize natural organic matter and, when utilizing these instruments, researchers must make multiple decisions regarding sample pre-treatment and the instrument ionization mode. To identify how these choices alter organic matter characterization and resulting conclusions, we analyzed a collection of 17 riverine samples from East River, CO (USA) under four PPL-based Solid Phase Extraction (SPE) treatment and electrospray ionization polarity (e.g., positive and negative) combinations: SPE (+), SPE (-), non-SPE (-), and non-SPE (+). The greatest number of formula assignments were achieved with SPE-treated samples due to the removal of compounds that could interfere with ionization. Furthermore, the SPE (-) treatment captured the most formulas across the widest chemical compound diversity. In addition to a reduced number of assigned formulas, the non-SPE datasets resulted in altered thermodynamic interpretations that could cascade into incomplete assumptions about the availability of organic matter pools for microbial heterotrophic respiration. Thus, we infer that the SPE (-) treatment is the best single method for characterizing environmental organic matter pools unless the focus is on lipid-like compounds, in which case we recommend a combination of SPE (-) and SPE (+) to adequately characterize these molecules.

International Listening Post report summary: the world at the dawn of 2019

2019 ◽  
Vol 19 (1) ◽  
pp. 121-124
Author(s):  
Sandy Henderson ◽  
Ulrike Beland ◽  
Dimitrios Vonofakos
Keyword(s):  
South Africa ◽  
Faroe Islands ◽  
The South ◽  
The World ◽  
The Uk

On or around 9 January 2019, twenty-two Listening Posts were conducted in nineteen countries: Canada, Chile, Denmark, Faroe Islands, Finland, Germany (Frankfurt and Berlin), Hungary, India, Ireland, Israel, Italy (two in Milan and one in the South), Peru, Serbia, South Africa, Spain, Sweden, Taiwan, Turkey, and the UK. This report synthesises the reports of those Listening Posts and organises the data yielded by them into common themes and patterns.

Basic principles for assessing the safety of fish products from the ponds exposed to the influence of nuclear fuel cycle enterprises

2019 ◽  
pp. 106-114
Author(s):  
A. V. Trapeznikov ◽  
V. N. Trapeznikova ◽  
A. V. Korzhavin ◽  
V. N. Nikolkin ◽  
A. P. Plataev
Keyword(s):  
Fuel Cycle ◽  
Specific Activity ◽  
River System ◽  
Food Product ◽  
Human Consumption ◽  
Basic Principles ◽  
Fish Products ◽  
Permissible Levels ◽  
Irtysh River

Relevance. In connection with the development of nuclear energy, many aquatic ecosystems have been exposed to radioactive substances. Fish, as an element of biota, is capable to accumulate radionuclides. However, fish is a traditional food. The control of the technogenic radionuclides accumulation level in the ichthyofauna is an important link in ensuring human security.Intention. To analyze the long-term data on the content of long-lived technogenic radionuclides 90Sr and 137Cs in the ichthyofauna of the Ob-Irtysh river system for the period from 2004 to 2016 and Beloyarsky pond for the period from 1977 to 2018.Methodology. Fish as a food product was assessed according to two criteria: a) permissible levels of specific activity of radionuclides (SanPiN 2.3.2.1078-01); b) using the indicator of conformity B and the uncertainty of its definition В (GOST 32161-2013 and GOST 32163-2013).Results and Discussion. Fish of all species that live in the river Tetcha, is not suitable for food use according to the criteria of SanPiN 2.3.2.1078-01, GOST 32161-2013 and GOST 32163-2013. The fish of the Ob-Irtysh river system, the habitat of which is located outside the Tetcha, meets the requirements for fish products. In the period from 1977 to 1989 in the Beloyarsk pond the accumulations of technogenic radionuclides in fish in quantities exceeding sanitary and hygienic standards were possible. Currently, the fish of the Beloyarsky pond fully complies with the sanitary and hygienic requirements for the radiation factor and is safe for human consumption.Conclusion. In the ponds exposed to the atomic energy enterprises, it is necessary to continuously monitor the content of long-lived technogenic radionuclides in fish and assess their amount in accordance with the requirements of SanPiN 2.3.2.1078-01 and using the conformity indicator В and the uncertainty of its determination В. 

Sphagnum mosses (Sphagnaceae, Bryophyta) of South Ossetia (Caucasus)

2017 ◽  
Vol 51 ◽  
pp. 232-241 ◽  
Author(s):  
G. Ya. Doroshina ◽  
E. Yu. Kuzmina ◽  
I. A. Nikolajev
Keyword(s):  
The South ◽  
The Caucasus ◽  
South Ossetia ◽  
Sphagnum Mosses ◽  
Botanical Institute ◽  
Ecological Conditions ◽  
Komarov Botanical Institute ◽  
The World ◽  
First Time

Information on the Sphagnum mosses of the South Ossetia is generalized, the resulted list is presented. Nine species of Sphagnum are included in the list, whereabouts data and references to the publications are given, and the presence of a sample in the Herbarium of the Komarov Botanical Institute RAS (LE) is noted. The species Sphagnum platyphyllum (Lindb. ex Braithw.) Warnst. rarely occurring in the Caucasus is reported in the South Ossetia for the first time. The species was found in the Caucasus, South Ossetia, at the side of the Ertso Lake (42°28ʹN, 43°45ʹE), 1720 m a. s. l., among sedge thickets at the margin of the overgrowing lake. The peculiarities of its occurrence and ecological conditions are considered. Its distribution in the Caucasus and in the world is discussed.

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