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579 records – page 1 of 58.

[Abundance and diversity of methanotrophic Gammaproteobacteria in northern wetlands].

https://arctichealth.org/en/permalink/ahliterature259581
Source
Mikrobiologiia. 2014 Mar-Apr;83(2):204-14
Publication Type
Article
Author
O V Danilova
S N Dedysh
Source
Mikrobiologiia. 2014 Mar-Apr;83(2):204-14
Language
Russian
Publication Type
Article
Keywords
Biodiversity
Fresh Water - microbiology
Gammaproteobacteria - genetics - isolation & purification - metabolism
Hydrogen-Ion Concentration
In Situ Hybridization, Fluorescence
Methane - metabolism
Methylococcaceae - genetics
Methylocystaceae - genetics
Molecular Sequence Data
Oxygenases - genetics
Phylogeny
RNA, Ribosomal, 16S
Russia
Wetlands
Abstract
Numeric abundance, identity and pH preferences of methanotrophic Gammaproteobacteria (type I methanotrophs) inhabiting the northern acidic wetlands were studied. The rates of methane oxidation by peat samples from six-wetlands of European Northern Russia (pH 3.9-4.7) varied from 0.04 to 0.60 µg CH4 g(-1) peat h(-1). The number of cells revealed by hybridization with fluorochrome-labeled probes M84 + M705 specific for type I methanotrophs was 0.05-2.16 x 10(5) cells g(-1) dry peat, i.e. 0.4-12.5% of the total number of methanotrophs and 0.004-0.39% of the total number of bacteria. Analysis of the fragments of the pmoA gene encoding particulate methane monooxygenase revealed predominance of the genus Methylocystis (92% of the clones) in the studied sample of acidic peat, while the proportion of the pmoA sequences of type I methanotrophs was insignificant (8%). PCR amplification of the 16S rRNA gene fragments of type I methanotrophs with TypeIF-Type IR primers had low specificity, since only three sequences out of 53 analyzed belonged to methanotrophs and exhibited 93-99% similarity to those of Methylovulum, Methylomonas, and Methylobacter species. Isolates of type I methanotrophs obtained from peat (strains SH10 and 83A5) were identified as members of the species Methylomonaspaludis and Methylovulum miyakonense, respectively. Only Methylomonaspaludum SH10 was capable of growth in acidic media (pH range for growth 3.8-7.2 with the optimum at pH 5.8-6.2), while Methylovulum miyakonense 83A5 exhibited the typical growth characteristics of neutrophilic methanotrophs (pH range for growth 5.5-8.0 with the optimum at pH 6.5-7.5).
PubMed ID
25423724 View in PubMed
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Abundance of actinobacteria and production of geosmin and 2-methylisoborneol in Danish streams and fish ponds.

https://arctichealth.org/en/permalink/ahliterature83047
Source
FEMS Microbiol Ecol. 2005 Apr 1;52(2):265-78
Publication Type
Article
Date
Apr-1-2005
Author
Klausen Cecilie
Nicolaisen Mette H
Strobel Bjarne W
Warnecke Falk
Nielsen Jeppe L
Jørgensen Niels O G
Author Affiliation
Department of Ecology, Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg, Denmark.
Source
FEMS Microbiol Ecol. 2005 Apr 1;52(2):265-78
Date
Apr-1-2005
Language
English
Publication Type
Article
Keywords
Actinobacteria - genetics - isolation & purification - metabolism
Animals
Aquaculture
Bornanes - analysis - metabolism
Denmark
Fishes - physiology
Fresh Water - chemistry - microbiology
Naphthols - analysis - metabolism
Nitrogen - analysis - metabolism
Seasons
Abstract
Occurrence of the odours geosmin and 2-methylisoborneol (MIB) in freshwater environments indicates that odour-producing organisms are commonly occurring. In the present study, we assumed actinomycetes to be a major source of the odours. Seasonal concentrations of odours and abundance of Actinobacteria, which includes actinomycetes and other G+ and high GC bacteria, were determined in one oligotrophic and two eutrophic freshwater streams, as well as in aquacultures connected to these streams, in Denmark. Concentrations of geosmin and MIB ranged from 2 to 9 ng l(-1) and were lowest in the winter. Passage of stream water in the aquacultures increased the amount of geosmin and MIB by up to 55% and 110%, respectively. Densities of actinobacteria were determined by fluorescence in situ hybridization with catalyzed reporter deposition (CARD-FISH) technique and were found to make up from 4 to 38 x 10(7) cells l(-1), corresponding to 3-9% of the total bacterial populations. The lowest densities of actinobacteria occurred in the winter. Filamentous bacteria targeted by the FISH probe made up about 2.7-38% (average was 22%) of the actinobacteria and were expected to be actinomycetes. Combined microautoradiography and CARD-FISH demonstrated that 10-38% (incorporation of 3H-thymidine) and 41-65% (incorporation of 3H-leucine) of the actinobacteria were metabolically active. The proportion of active actinobacteria increased up to 2-fold during passage of stream water in the aquacultures, and up to 98% of the cells became active. Sequencing of 16S rRNA genes in 8 bacterial isolates with typical actinomycete morphology from the streams and ponds demonstrated that most of them belonged to the genus Streptomyces. The isolated actinomycetes produced geosmin at rates from 0.1 to 35 aggeosmin bacterium(-1)h(-1). MIB was produced at similar rates in 5 isolates, whereas no MIB was produced by three of the isolates. Addition of the odours to stream water demonstrated that indigenous stream bacteria were capable of reducing the odours, and that enrichment with LB medium stimulated the degradation. Our study shows that bacterial communities in freshwater include geosmin- and MIB-producing actinobacteria. However, the mechanisms controlling production as well as degradation of the odours in natural waters appear complex and require further research.
PubMed ID
16329912 View in PubMed
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Accumulated state of the Yukon River watershed: part I critical review of literature.

https://arctichealth.org/en/permalink/ahliterature121234
Source
Integr Environ Assess Manag. 2013 Jul;9(3):426-38
Publication Type
Article
Date
Jul-2013
Author
Monique G Dubé
Breda Muldoon
Julie Wilson
Karonhiakta'tie Bryan Maracle
Author Affiliation
Canadian Rivers Institute, University of New Brunswick, Alberta, Canada. Dub.mon@hotmail.com
Source
Integr Environ Assess Manag. 2013 Jul;9(3):426-38
Date
Jul-2013
Language
English
Publication Type
Article
Keywords
Alaska - epidemiology
Animal Migration
Animals
British Columbia - epidemiology
Climate change
Environment
Environmental Monitoring - methods
Fish Diseases - epidemiology - microbiology - parasitology
Fishes - physiology
Fresh Water - analysis - microbiology - parasitology
Humans
Neoplasms - chemically induced - epidemiology
Seasons
Water Movements
Water Pollutants, Chemical - analysis - metabolism - toxicity
Water Quality
Yukon Territory - epidemiology
Abstract
A consistent methodology for assessing the accumulating effects of natural and manmade change on riverine systems has not been developed for a whole host of reasons including a lack of data, disagreement over core elements to consider, and complexity. Accumulated state assessments of aquatic systems is an integral component of watershed cumulative effects assessment. The Yukon River is the largest free flowing river in the world and is the fourth largest drainage basin in North America, draining 855,000 km(2) in Canada and the United States. Because of its remote location, it is considered pristine but little is known about its cumulative state. This review identified 7 "hot spot" areas in the Yukon River Basin including Lake Laberge, Yukon River at Dawson City, the Charley and Yukon River confluence, Porcupine and Yukon River confluence, Yukon River at the Dalton Highway Bridge, Tolovana River near Tolovana, and Tanana River at Fairbanks. Climate change, natural stressors, and anthropogenic stresses have resulted in accumulating changes including measurable levels of contaminants in surface waters and fish tissues, fish and human disease, changes in surface hydrology, as well as shifts in biogeochemical loads. This article is the first integrated accumulated state assessment for the Yukon River basin based on a literature review. It is the first part of a 2-part series. The second article (Dubé et al. 2013a, this issue) is a quantitative accumulated state assessment of the Yukon River Basin where hot spots and hot moments are assessed outside of a "normal" range of variability.
PubMed ID
22927161 View in PubMed
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[Accumulation and distribution of 137Cs and 90Sr radionuclides in the components of water-bottom sediments-macrophytes of Lake Malye Kirpichiky].

https://arctichealth.org/en/permalink/ahliterature263700
Source
Radiats Biol Radioecol. 2014 Nov-Dec;54(6):650-6
Publication Type
Article
Author
K V Kablova
V V Deryagin
S G Levina
A A Sutyagin
Source
Radiats Biol Radioecol. 2014 Nov-Dec;54(6):650-6
Language
Russian
Publication Type
Article
Keywords
Cesium Radioisotopes - analysis
Ecosystem
Fresh Water
Geologic Sediments - analysis
Humans
Lakes
Radioactive Hazard Release
Russia
Strontium Radioisotopes - analysis
Water Pollutants, Radioactive - analysis
Abstract
This research work is devoted to analyzing the processes of accumulation and distribution of long-lived radionuclides of 90Sr and 137Cs in the components of water-sediment-macrophytes of Lake Malye Kirpichiky (Chelyabinsk region). The characteristic features of redistribution of radioactive substances, depending on the texture of the bottom sediments of the lake and the species composition of aquatic vegetation are shown. Also shown is the total stock of radionuclides in water and bottom sediments. The coefficients of 90Sr and 137Cs accumulation in bottom sediments and macrophytes have been calculated.
PubMed ID
25980292 View in PubMed
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Accumulation features and temporal trends of PCDDs, PCDFs and PCBs in Baikal seals (Pusa sibirica).

https://arctichealth.org/en/permalink/ahliterature90631
Source
Environ Pollut. 2009 Mar;157(3):737-47
Publication Type
Article
Date
Mar-2009
Author
Imaeda Daisuke
Kunisue Tatsuya
Ochi Yoko
Iwata Hisato
Tsydenova Oyuna
Takahashi Shin
Amano Masao
Petrov Evgeny A
Batoev Valeriy B
Tanabe Shinsuke
Author Affiliation
Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan.
Source
Environ Pollut. 2009 Mar;157(3):737-47
Date
Mar-2009
Language
English
Publication Type
Article
Keywords
Adipose Tissue - chemistry - metabolism
Animals
Body Burden
Ecotoxicology - methods
Environmental Pollutants - analysis - pharmacokinetics
Female
Fresh Water
Male
Polychlorinated Biphenyls - analysis - pharmacokinetics
Seals, Earless - metabolism
Siberia
Tetrachlorodibenzodioxin - analogs & derivatives - analysis - pharmacokinetics
Time Factors
Abstract
This study investigated the accumulation features and temporal trends of PCDD/Fs, dioxin-like PCBs (DL-PCBs) and non-dioxin-like PCBs (NDL-PCBs) in the blubber of Baikal seals collected in 1992 and 2005. DL-PCBs (480-3600ng/g) and NDL-PCBs (980-35,000ng/g) were dominant contaminants. Concentrations of PCDDs and PCBs in males were significantly higher than in females. In males, age-dependent accumulation was observed for PCDDs, mono-ortho PCBs and NDL-PCBs. PCDFs and non-ortho PCBs showed no such trends, implying that exposure of seals to these contaminants has been decreasing in recent years. No decreasing temporal trend was observed for PCDDs, mono-ortho PCBs and NDL-PCBs, suggesting that Baikal seals are still exposed to PCDDs and PCBs. TEQs of PCDDs and mono-ortho PCBs in seals collected in 2005 accounted for 62-77% of total TEQs. The TEQ levels in 40% of the specimens exceeded the threshold level for immunosuppression observed in harbor seals (209pg/g).
PubMed ID
19110354 View in PubMed
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Acidification remediation alternatives: exploring the temporal dimension with cost benefit analysis.

https://arctichealth.org/en/permalink/ahliterature143359
Source
Ambio. 2010 Feb;39(1):40-8
Publication Type
Article
Date
Feb-2010
Author
Göran Bostedt
Stefan Löfgren
Sophia Innala
Kevin Bishop
Author Affiliation
Department of Forest Economics, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden. goran.bostedt@sekon.slu.se
Source
Ambio. 2010 Feb;39(1):40-8
Date
Feb-2010
Language
English
Publication Type
Article
Keywords
Conservation of Natural Resources
Cost-Benefit Analysis
Ecosystem
Environmental Monitoring - economics
Environmental Remediation - economics
Fresh Water - analysis - chemistry
Humans
Hydrogen-Ion Concentration
Socioeconomic Factors
Soil - analysis
Sulfur Compounds
Sweden
Time Factors
Water Pollutants, Chemical - adverse effects - economics
Abstract
Acidification of soils and surface waters caused by acid deposition is still a major problem in southern Scandinavia, despite clear signs of recovery. Besides emission control, liming of lakes, streams, and wetlands is currently used to ameliorate acidification in Sweden. An alternative strategy is forest soil liming to restore the acidified upland soils from which much acidified runoff originates. This cost-benefit analysis compared these liming strategies with a special emphasis on the time perspective for expected benefits. Benefits transfer was used to estimate use values for sport ffishing and nonuse values in terms of existence values. The results show that large-scale forest soil liming is not socioeconomically profitable, while lake liming is, if it is done efficiently-in other words, if only acidified surface waters are treated. The beguiling logic of "solving" an environmental problem at its source (soils), rather than continuing to treat the symptoms (surface waters), is thus misleading.
Notes
Cites: Nature. 2007 Nov 22;450(7169):537-4018033294
PubMed ID
20496651 View in PubMed
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[A laboratory model of the cyanobacterial mat from the Kotel'nikovskii hot spring (Baikal Region)]

https://arctichealth.org/en/permalink/ahliterature91824
Source
Mikrobiologiia. 2008 Jul-Aug;77(4):551-7
Publication Type
Article
Author
Brianskaia A V
Orleanskii V K
Dagurova O P
Source
Mikrobiologiia. 2008 Jul-Aug;77(4):551-7
Language
Russian
Publication Type
Article
Keywords
Fresh Water - microbiology
Hot Springs - microbiology
Hot Temperature
Models, Biological
Oscillatoria - cytology - isolation & purification - physiology
Siberia
Water Microbiology
Abstract
A laboratory model of the cyanobacterial community of the Kotel'nikovskii hot spring (Baikal Region) was developed. A step-by-step description of the algocenosis formation along both the time and temperature gradient was given. The natural and laboratory mats were compared, and the major differences in the qualitative and quantitative composition of the cyanobacterial community were revealed. The laboratory algocenosis was stratified by species composition and was characterized by rapid replacement of the dominant cyanobacterial species depending on the temperature gradient. The formation of the community structure occurred over the 18 days of the experiment. In space and time, the sequence of species emergence in the cyanobacterial mat was as follows: Mastigocladus laminosus --> Phormidium tenue --> Ph. ambiguum --> Ph. valderiae. The species composition of the laboratory mat was similar to that of the natural mat; however it was found to be less diverse.
PubMed ID
18825983 View in PubMed
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[A Legionella circulation study in the central Volga Valley area].

https://arctichealth.org/en/permalink/ahliterature220029
Source
Zh Mikrobiol Epidemiol Immunobiol. 1993 Nov-Dec;(6):52-3
Publication Type
Article

Altitudinal and thermal gradients of hepatic Cyp1A gene expression in natural populations of Salmo trutta from high mountain lakes and their correlation with organohalogen loads.

https://arctichealth.org/en/permalink/ahliterature98080
Source
Environ Pollut. 2010 May;158(5):1392-8
Publication Type
Article
Date
May-2010
Author
Sergio Jarque
Eva Gallego
Mireia Bartrons
Jordi Catalan
Joan O Grimalt
Benjamin Piña
Author Affiliation
Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia, Spain.
Source
Environ Pollut. 2010 May;158(5):1392-8
Date
May-2010
Language
English
Publication Type
Article
Keywords
Altitude
Animals
Cytochrome P-450 CYP1A1 - genetics - metabolism
Environmental monitoring
Environmental Pollutants - analysis - toxicity
Fish Proteins - genetics - metabolism
Fresh Water - analysis
Gene Expression - drug effects
Hydrocarbons, Halogenated - analysis - toxicity
Liver - enzymology
Norway
Temperature
Trout - metabolism
Abstract
The biomarker of xenobiotic exposure cytochrome p450A1 (Cyp1A) was used to analyze the biological response to chemical pollution in Salmo trutta (brown trout) from nine high mountain European lakes in Norway, Tatras, Tyrol, and central Pyrenees. Hepatic Cyp1A mRNA levels correlated both with the reciprocal of absolute annual average air temperatures of the sampled lakes and with muscle concentrations of several hydrophobic organohalogen compounds (OC), including chlorinated polychlorobiphenyls (PCB), DDE, and DDT. The correlation between Cyp1A expression and OC content was observed across the whole temperature range (between -0.7 degrees C and +6.2 degrees C), but also in the absence of any thermal gradient. We concluded that airborne pollutants accumulate in high mountain lake fish at concentrations high enough to increase Cyp1A expression, among other possible effects. As geographical distribution of semi-volatile OC is strongly influenced by air temperatures, future climate modifications will potentially enhance their physiological effects in lake ecosystems.
PubMed ID
20149942 View in PubMed
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579 records – page 1 of 58.