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552 records – page 1 of 56.

30 years of data reveal dramatic increase in abundance of brown trout following the removal of a small hydrodam.

https://arctichealth.org/en/permalink/ahliterature292608
Source
J Environ Manage. 2017 Dec 15; 204(Pt 1):467-471
Publication Type
Journal Article
Date
Dec-15-2017
Author
Kim Birnie-Gauvin
Martin H Larsen
Jan Nielsen
Kim Aarestrup
Author Affiliation
DTU Aqua, Section for Freshwater Fisheries and Ecology, Vejlsøvej 39, 8600 Silkeborg, Denmark. Electronic address: kbir@aqua.dtu.dk.
Source
J Environ Manage. 2017 Dec 15; 204(Pt 1):467-471
Date
Dec-15-2017
Language
English
Publication Type
Journal Article
Keywords
Animals
Conservation of Natural Resources - methods
Denmark
Ecosystem
Rivers
Trout
Water Movements
Abstract
Humans and freshwater ecosystems have a long history of cohabitation. Today, nearly all major rivers of the world have an in-stream structure which changes water flow, substrate composition, vegetation, and fish assemblage composition. The realization of these effects and their subsequent impacts on population sustainability and conservation has led to a collective effort aimed to find ways to mitigate these impacts. Barrier removal has recently received greater interest as a potential solution to restore river connectivity, and reestablish high quality habitats, suitable for feeding, refuge and spawning of fish. In the present study, we present thirty years of data from electrofishing surveys obtained at two sites, both prior to and following the removal of a small-scale hydropower dam in Central Jutland, Denmark. We demonstrate that the dam removal has led to a dramatic increase in trout density, especially in young of the year. Surprisingly, we found that this increase was not just upstream of the barrier, where the ponded zone previously was, but also downstream of the barrier, despite little changes in habitat in that area. These findings suggest that barrier removal may be the soundest conservation option to reinstate fish population productivity.
PubMed ID
28923580 View in PubMed
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[90Sr in residents of the Iset riverside settlements].

https://arctichealth.org/en/permalink/ahliterature144798
Source
Radiats Biol Radioecol. 2010 Jan-Feb;50(1):90-7
Publication Type
Article
Author
E I Tolstykh
L M Peremyslova
N B Shagina
M O Degteva
Source
Radiats Biol Radioecol. 2010 Jan-Feb;50(1):90-7
Language
Russian
Publication Type
Article
Keywords
Bone and Bones - chemistry
Humans
Radiation monitoring
Radioactive Hazard Release
Retrospective Studies
Rivers - chemistry
Rural Population
Siberia
Strontium Radioisotopes - analysis
Water Pollutants, Radioactive - analysis
Abstract
The river Iset belongs to the Techa-Iset-Tobol-Irtysh-Ob system contaminated by liquid radioactive wastes from Mayak plutonium facility in 1949-1956. This study represents the first retrospective analysis of postmortem measurements of 90Sr in bones from residents of the Iset riverside settlements in 1960-1982. It was shown that 90Sr concentration in bones of residents lived in settlements located downstream from the Techa river mouth (Shadrinsk, Isetskoye, Yalutorovsk) was 5 times higher than average 90Sr concentration in bones of the Russian residents. There was not statistically significant difference in accumulated 90Sr in bones between residents of the considered Iset' settlements indicating similar levels of 90Sr ingestion. Dietary 90Sr intake was reconstructed from the measurements of the radionuclide in bones. Total 90Sr dietary intake in 1950-1975 was 68 kBq; and 90% of the intake occurred in 1950-1961. In 1960s, 90Sr-contamination of the diet in settlements located downstream from the Techa river mouth was mostly (by 70%) due to global fallouts. Absorbed dose in the red bone marrow cumulated over 25 years of exposure was equal to 14 (4.7-42) mGy.
PubMed ID
20297686 View in PubMed
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Accumulation and exchange of parasites during adaptive radiation in an ancient lake.

https://arctichealth.org/en/permalink/ahliterature301785
Source
Int J Parasitol. 2018 03; 48(3-4):297-307
Publication Type
Journal Article
Date
03-2018
Author
Joseph E Ironside
Toby J Wilkinson
Author Affiliation
Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, Ceredigion SY23 3DA, United Kingdom. Electronic address: jei@aber.ac.uk.
Source
Int J Parasitol. 2018 03; 48(3-4):297-307
Date
03-2018
Language
English
Publication Type
Journal Article
Keywords
Adaptation, Biological
Amphipoda - classification - parasitology - physiology
Animals
Bayes Theorem
Biodiversity
Cloning, Molecular
DNA, Fungal - chemistry
DNA, Ribosomal - chemistry
Europe
Host Specificity
Lakes - parasitology
Microsporidia - classification - genetics - growth & development
Phylogeny
Ponds - parasitology
Rivers - parasitology
Russia
Abstract
In the ancient Lake Baikal, Russia, amphipod crustaceans have undergone a spectacular adaptive radiation, resulting in a diverse community of species. A survey of microsporidian parasites inhabiting endemic and non-endemic amphipod host species at the margins of Lake Baikal indicates that the endemic amphipods harbour many microsporidian parasite groups associated with amphipods elsewhere in Eurasia. While these parasites may have undergone a degree of adaptive radiation within the lake, there is little evidence of host specificity. Furthermore, a lack of reciprocal monophyly indicates that exchanges of microsporidia between Baikalian and non-Baikalian hosts have occurred frequently in the past and may be ongoing. Conversely, limitations to parasite exchange between Baikalian and non-Baikalian host populations at the margins of the lake are implied by differences in parasite prevalence and lack of shared microsporidian haplotypes between the two host communities. While amphipod hosts have speciated sympatrically within Lake Baikal, the parasites appear instead to have accumulated, moving into the lake from external amphipod populations on multiple occasions to exploit the large and diverse community of endemic amphipods in Lake Baikal.
PubMed ID
29273284 View in PubMed
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[Accumulation of radionuclides in food chains of the Yenisei River after the nuclear power plant shutdown at the mining-and-chemical enterprise].

https://arctichealth.org/en/permalink/ahliterature261756
Source
Radiats Biol Radioecol. 2014 Jul-Aug;54(4):405-14
Publication Type
Article
Author
T A Zotina
E A Trofimova
A D Karpov
A Ia Bolsunovskii
Source
Radiats Biol Radioecol. 2014 Jul-Aug;54(4):405-14
Language
Russian
Publication Type
Article
Keywords
Animals
Biota
Chemical Industry
Fishes - metabolism
Food chain
Industrial Waste - analysis
Mining
Muscle, Skeletal - radionuclide imaging
Nuclear Power Plants
Radiation Monitoring - methods
Radioisotopes - analysis - pharmacokinetics
Rivers - chemistry
Seasons
Siberia
Water Pollutants, Radioactive - analysis - pharmacokinetics
Abstract
Accumulation of artificial and natural radionuclides in the chains of food webs leading to non-predatory and piscivorous fish of the Yenisei River was investigated during one year before and three years after the shutdown of a nuclear power plant at the Mining-and-Chemical Combine (2009-2012). The activity of artificial radionuclides in the samples of biota ofthe Yenisei River (aquatic moss, gammarids, dace, grayling, pike) was estimated. The concentration of radionuclides with induced activity (51Cr, 54Mn, 58Co, 60Co, 65Zn, 141, 144Ce, 152, 154Eu, 239Np) decreased in the biomass of biota after the shutdown of the nuclear power plant; the concentration of 137Cs did not. Analysis of the accumulation factors (C(F)) allows us to expect the effective accumulation of 137Cs in the terminal level of the food web of the Yenisei River--pike (C(F) = 2.0-9.4), i.e. biomagnifications of radiocesium. Accumulation of artificial, radionuclides in non-predatory fish from gammarids was not effective (C(F)
PubMed ID
25775829 View in PubMed
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[Adaptive response of blood lymphocytes as a marker of hemopoiesis status in exposed persons].

https://arctichealth.org/en/permalink/ahliterature126505
Source
Radiats Biol Radioecol. 2011 Nov-Dec;51(6):645-50
Publication Type
Article
Author
A V Akleev
A V Aleshchenko
O V Kudriashova
L P Semenova
A M Serebrianyi
O I Khudiakova
I I Pelevina
Source
Radiats Biol Radioecol. 2011 Nov-Dec;51(6):645-50
Language
Russian
Publication Type
Article
Keywords
Adaptation, Physiological
Adult
Aged
Bone Marrow Cells - radiation effects
Dose-Response Relationship, Radiation
Female
Hematopoiesis - radiation effects
Hematopoietic Stem Cells - radiation effects
Humans
Industrial Waste - adverse effects
Lymphocyte Count
Lymphocytes - cytology - physiology - radiation effects
Male
Middle Aged
Radiation, Ionizing
Rivers
Russia
Strontium Radioisotopes - adverse effects
Water Pollution, Radioactive - adverse effects
Abstract
An obvious correlation between the type of reaction manifested by peripheral blood lymphocytes to low dose irradiation in vitro (adaptive potential), the RBM cell composition (during the period of the major exposure), and the peripheral blood cell composition (at a late time period coincident with the studies of induced radioresistance) has been found in the Techa riverside residents in the later periods after the onset of a long-term low-dose rate radiation exposure (55-60 years later) within a range of individual red bone marrow doses from 0.01 to 1.79 Gy. The nature of these dependences observed in chronically exposed individuals differs from that revealed in the controls. It can be suggested based on the results of the study that the capacity for the adaptive response shown by peripheral blood lymphocytes donated by exposed persons in the remote period after exposure can be regarded as a biological marker of the functional state of the hemopoietic stem cell pool.
PubMed ID
22384713 View in PubMed
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Aerial surveys cause large but ephemeral decreases in bear presence at salmon streams in Kodiak, Alaska.

https://arctichealth.org/en/permalink/ahliterature309083
Source
PLoS One. 2019; 14(9):e0222085
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Date
2019
Author
William W Deacy
William B Leacock
Eric J Ward
Jonathan B Armstrong
Author Affiliation
Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, United States of America.
Source
PLoS One. 2019; 14(9):e0222085
Date
2019
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Alaska
Animal Distribution
Animals
Biomass
Ecosystem
Female
Male
Remote Sensing Technology - adverse effects - methods - standards
Rivers
Salmon - physiology
Ursidae - physiology
Abstract
Aerial surveys are often used to monitor wildlife and fish populations, but rarely are the effects on animal behavior documented. For over 30 years, the Kodiak National Wildlife Refuge has conducted low-altitude aerial surveys to assess Kodiak brown bear (Ursus arctos middendorffi) space use and demographic composition when bears are seasonally congregated near salmon spawning streams in southwestern Kodiak Island, Alaska. Salmon (Oncorhynchus spp.) are an important bear food and salmon runs are brief, so decreases in time spent fishing for salmon may reduce salmon consumption by bears. The goal of this study was to apply different and complementary field methods to evaluate the response of bears to these aerial surveys. Ground-based counts at one stream indicated 62% of bears departed the 200m-wide survey zone in response to aerial surveys, but bear counts returned to pre-survey abundance after only three hours. Although this effect was brief, survey flights occurred during the hours of peak daily bear activity (morning and evening), so the three-hour disruption appeared to result in a 25% decline in cumulative daily detections by 38 time-lapse cameras deployed along 10 salmon streams. Bear responses varied by sex-male bears were much more likely than female bears (with or without cubs) to depart streams and female bears with GPS collars did not move from streams following surveys. Although bears displaced by aerial surveys may consume fewer salmon, the actual effect on their fitness depends on whether they compensate by foraging at other times or by switching to other nutritious resources. Data from complementary sources allows managers to more robustly understand the impacts of surveys and whether their benefits are justified. Similar assessments should be made on alternative techniques such as Unmanned Aerial Vehicles and non-invasive sampling to determine whether they supply equivalent data while limiting bear disturbance.
PubMed ID
31504063 View in PubMed
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[AEROMONAS BACTERIA ISOLATED FROM BITHYNIIDAE MOLLUSKS AND THEIR HABITATS: SPECIES COMPOSITION AND BIOLOGICAL PROPERTIES. COMMUNICATION 1].

https://arctichealth.org/en/permalink/ahliterature265353
Source
Med Parazitol (Mosk). 2015 Apr-Jun;(2):20-3
Publication Type
Article
Author
T F Stepanova
O V Bukharin
L V Kataeva
N B Perunova
N F Karpukhina
Source
Med Parazitol (Mosk). 2015 Apr-Jun;(2):20-3
Language
Russian
Publication Type
Article
Keywords
Aeromonas - classification - isolation & purification
Animals
Rivers - microbiology
Siberia
Snails - microbiology
Water Microbiology
Abstract
The purpose of this investigation was to study the species composition and biological properties of Aeromonas bacteria isolated from Bithyniidae mollusks and their habitat (a water reservoir). The Bithyniidae mollusks and water from their habitat were the material to be studied. A total of 176 Aeromonas strains were isolated from the mollusks and water. A. veronii, A. hydrophila, and A. ichthiosmia were most common in the mollusks and A. veronii and A. ichthiosmia were in the water. All the strains isolated had hemolytic activity and no lysozyme or plasma coagulase activity. The magnitude of lecithinase and antilysozymic activities and biofilm formation of the Aeromonas bacteria varied with the isolation source of their strains.
PubMed ID
26152033 View in PubMed
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Age-dependent accumulation of (137)Cs by pike Esox lucius in the Yenisei River.

https://arctichealth.org/en/permalink/ahliterature279980
Source
Dokl Biol Sci. 2016 May;468(1):133-6
Publication Type
Article
Date
May-2016
Author
T A Zotina
E A Trofimova
D V Dementyev
A Ya Bolsunovsky
Source
Dokl Biol Sci. 2016 May;468(1):133-6
Date
May-2016
Language
English
Publication Type
Article
Keywords
Aging
Animals
Cesium Radioisotopes - metabolism
Esocidae - metabolism
Muscle, Skeletal - metabolism
Rivers
Siberia
Abstract
Age-dependent accumulation of (137)Cs in the muscles and bodies of the pike Esox lucius (aged two to seven years) inhabiting a section of the Yenisei River polluted with artificial radionuclides has been studied. The content of (137)Cs in muscles varied from 0.5 to 7.0 Bq/kg of fresh weight. The maximum content of the radionuclide has been found in juveniles. The content of (137)Cs in pike muscles and body decreased considerably with age. The high content of (137)Cs in the muscles of juveniles is probably a consequence of their higher intensity of feeding as compared to older individuals, which is due to the intense growth of juveniles.
PubMed ID
27411826 View in PubMed
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Allochthonous inputs of riverine picocyanobacteria to coastal waters in the Arctic Ocean.

https://arctichealth.org/en/permalink/ahliterature95689
Source
FEMS Microbiol Ecol. 2007 Feb;59(2):356-65
Publication Type
Article
Date
Feb-2007
Author
Waleron Malgorzata
Waleron Krzysztof
Vincent Warwick F
Wilmotte Annick
Author Affiliation
Centre for Protein Engineering, Institute of Chemistry B6, Sart Tilman, University of Liège, Liège, Belgium.
Source
FEMS Microbiol Ecol. 2007 Feb;59(2):356-65
Date
Feb-2007
Language
English
Publication Type
Article
Keywords
Arctic Regions
Climate
Cyanobacteria - classification - genetics
DNA, Bacterial - analysis
DNA, Ribosomal - analysis
Gene Library
Molecular Sequence Data
Phylogeny
Plastids - genetics
RNA, Ribosomal, 16S - genetics
Rivers - microbiology
Seawater - microbiology
Sequence Analysis, DNA
Abstract
The observed onset of climate change at high northern latitudes has highlighted the need to establish current baseline conditions in the Arctic Ocean, and has raised concern about the potential for the invasion and growth of biota that have warm temperature optima, such as cyanobacteria. In this study, we used 16S rRNA gene sequences as a molecular marker to evaluate the hypothesis that Arctic rivers provide a major inoculum of cyanobacteria into the coastal Arctic Ocean. Surface samples were collected along a transect extending from the Mackenzie River (Northwest Territories, Canada), across its estuary, to 200 km offshore at the edge of the perennial Arctic pack ice (Beaufort Sea). The highest picocyanobacteria concentrations occurred in the river, with concentrations an order of magnitude lower at offshore marine stations. The 16S rRNA gene clone libraries of five surface samples and five strains along this gradient showed that the cyanobacterial sequences were divided into eight operational taxonomic units (OTUs), six OTUs closely related to freshwater and brackish Synechococcus and two OTUs of filamentous cyanobacteria. No typically marine Synechococcus sequences and no Prochlorococcus sequences were recovered. These results are consistent with the hypothesis of an allochthonous origin of picocyanobacteria in the coastal Arctic Ocean, and imply survival but little net growth of picocyanobacteria under the present conditions in northern high-latitude seas.
PubMed ID
17132157 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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552 records – page 1 of 56.