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134 records – page 1 of 14.

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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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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Air-water exchange of brominated anisoles in the northern Baltic Sea.

https://arctichealth.org/en/permalink/ahliterature260092
Source
Environ Sci Technol. 2014 Jun 3;48(11):6124-32
Publication Type
Article
Date
Jun-3-2014
Author
Terry F Bidleman
Kathleen Agosta
Agneta Andersson
Peter Haglund
Olle Nygren
Matyas Ripszam
Mats Tysklind
Source
Environ Sci Technol. 2014 Jun 3;48(11):6124-32
Date
Jun-3-2014
Language
English
Publication Type
Article
Keywords
Air Movements
Air Pollutants - analysis - chemistry
Anisoles - analysis - chemistry
Bromine - analysis - chemistry
Environmental monitoring
Oceans and Seas
Salinity
Seawater - analysis - chemistry
Sweden
Volatilization
Water Movements
Water Pollutants, Chemical - analysis - chemistry
Abstract
Bromophenols produced by marine algae undergo O-methylation to form bromoanisoles (BAs), which are exchanged between water and air. BAs were determined in surface water of the northern Baltic Sea (Gulf of Bothnia, consisting of Bothnian Bay and Bothnian Sea) during 2011-2013 and on a transect of the entire Baltic in September 2013. The abundance decreased in the following order: 2,4,6-tribromoanisole (2,4,6-TBA)>2,4-dibromoanisole (2,4-DBA)»2,6-dibromoanisole (2,6-DBA). Concentrations of 2,4-DBA and 2,4,6-TBA in September were higher in the southern than in the northern Baltic and correlated well with the higher salinity in the south. This suggests south-to-north advection and dilution with fresh riverine water enroute, and/or lower production in the north. The abundance in air over the northern Baltic also decreased in the following order: 2,4,6-TBA>2,4-DBA. However, 2,6-DBA was estimated as a lower limit due to breakthrough from polyurethane foam traps used for sampling. Water/air fugacity ratios ranged from 3.4 to 7.6 for 2,4-DBA and from 18 to 94 for 2,4,6-TBA, indicating net volatilization. Flux estimates using the two-film model suggested that volatilization removes 980-1360 kg of total BAs from Bothnian Bay (38000 km2) between May and September. The release of bromine from outgassing of BAs could be up to 4-6% of bromine fluxes from previously reported volatilization of bromomethanes and bromochloromethanes.
PubMed ID
24811233 View in PubMed
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Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years.

https://arctichealth.org/en/permalink/ahliterature294791
Source
Nature. 2018 04; 556(7700):227-230
Publication Type
Historical Article
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Date
04-2018
Author
David J R Thornalley
Delia W Oppo
Pablo Ortega
Jon I Robson
Chris M Brierley
Renee Davis
Ian R Hall
Paola Moffa-Sanchez
Neil L Rose
Peter T Spooner
Igor Yashayaev
Lloyd D Keigwin
Author Affiliation
Department of Geography, University College London, London, UK. d.thornalley@cantab.net.
Source
Nature. 2018 04; 556(7700):227-230
Date
04-2018
Language
English
Publication Type
Historical Article
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Arctic Regions
Atlantic Ocean
Climate Change - statistics & numerical data
Convection
Fresh Water - analysis
Greenland
History, 15th Century
History, 16th Century
History, 17th Century
History, 18th Century
History, 19th Century
History, 20th Century
History, 21st Century
History, Medieval
Ice Cover - chemistry
Newfoundland and Labrador
Oceans and Seas
Reproducibility of Results
Seawater - analysis
Time Factors
Water Movements
Abstract
The Atlantic meridional overturning circulation (AMOC) is a system of ocean currents that has an essential role in Earth's climate, redistributing heat and influencing the carbon cycle1, 2. The AMOC has been shown to be weakening in recent years 1 ; this decline may reflect decadal-scale variability in convection in the Labrador Sea, but short observational datasets preclude a longer-term perspective on the modern state and variability of Labrador Sea convection and the AMOC1, 3-5. Here we provide several lines of palaeo-oceanographic evidence that Labrador Sea deep convection and the AMOC have been anomalously weak over the past 150 years or so (since the end of the Little Ice Age, LIA, approximately AD 1850) compared with the preceding 1,500 years. Our palaeoclimate reconstructions indicate that the transition occurred either as a predominantly abrupt shift towards the end of the LIA, or as a more gradual, continued decline over the past 150 years; this ambiguity probably arises from non-AMOC influences on the various proxies or from the different sensitivities of these proxies to individual components of the AMOC. We suggest that enhanced freshwater fluxes from the Arctic and Nordic seas towards the end of the LIA-sourced from melting glaciers and thickened sea ice that developed earlier in the LIA-weakened Labrador Sea convection and the AMOC. The lack of a subsequent recovery may have resulted from hysteresis or from twentieth-century melting of the Greenland Ice Sheet 6 . Our results suggest that recent decadal variability in Labrador Sea convection and the AMOC has occurred during an atypical, weak background state. Future work should aim to constrain the roles of internal climate variability and early anthropogenic forcing in the AMOC weakening described here.
Notes
CommentIn: Nature. 2018 Apr;556(7700):149 PMID 29643490
CommentIn: Nature. 2018 Apr;556(7700):180-181 PMID 29636556
PubMed ID
29643484 View in PubMed
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Anthropogenic iodine-129 in the Arctic Ocean and Nordic Seas: numerical modeling and prognoses.

https://arctichealth.org/en/permalink/ahliterature172161
Source
Mar Pollut Bull. 2006 Apr;52(4):380-5
Publication Type
Article
Date
Apr-2006
Author
V. Alfimov
G. Possnert
A. Aldahan
Author Affiliation
Tandem Laboratory, Uppsala University, Sweden. alfimovv@phys.ethz.ch
Source
Mar Pollut Bull. 2006 Apr;52(4):380-5
Date
Apr-2006
Language
English
Publication Type
Article
Keywords
Arctic Regions
Computer simulation
Geography
Humans
Iodine Radioisotopes - analysis
Models, Theoretical
Oceans and Seas
Time Factors
Water Movements
Water Pollutants, Radioactive - analysis - metabolism
Abstract
A numerical model simulation has been used to predict extent and variability in the anthropogenic (129)I pollution in the Arctic Ocean and Nordic Seas region over a period of 100 years. The source function of (129)I used in the model is represented by a well-known history of discharges from the Sellafield and La Hague nuclear reprocessing facilities. The simulations suggest a fast transport and large inventory of the anthropogenic (129)I in the Arctic and North Atlantic Oceans. In a fictitious case of abrupt stop of the discharges, a rapid decline of inventories is observed in all compartments except the North Atlantic Ocean, the deep Nordic Seas and the deep Arctic Ocean. Within 15 years after the stop of releases, the model prediction indicates that near-equilibrium conditions are reached in all compartments.
PubMed ID
16266731 View in PubMed
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Assessing receptivity for change in urban stormwater management and contexts for action.

https://arctichealth.org/en/permalink/ahliterature266348
Source
J Environ Manage. 2014 Dec 15;146:29-41
Publication Type
Article
Date
Dec-15-2014
Author
Annicka Cettner
Richard Ashley
Annelie Hedström
Maria Viklander
Source
J Environ Manage. 2014 Dec 15;146:29-41
Date
Dec-15-2014
Language
English
Publication Type
Article
Keywords
Conservation of Natural Resources
Humans
Policy
Questionnaires
Rain
Sweden
Urban health
Water Movements
Water supply
Abstract
Individual and organisational receptivity for change towards the use of sustainable stormwater management systems has been previously examined, but the significance of the different contexts for achieving this has been largely unexplored. This paper examines the significance of contexts associated to the actions to bring this about by proposing and evaluating an emerging framework based on two related receptivity theories: the individual or organisational approach and the contextual approach. Results from a Swedish national questionnaire with professionals in stormwater management have been used, together with a limited number of interviews to develop and understand the validity of the framework. The analysis has indicated that the respondents were professionally prepared for change (action) but not practically prepared due to inadequate supportive contexts. In response, a number of potential contexts associated to the necessary actions were identified. The framework was found to provide new insights into the influence of receptive contexts for a change in water management practice. These insights can be used by policy makers and others to better support the realization of professional openness for change and thus accelerate the process of change to sustainable stormwater practice.
PubMed ID
25156263 View in PubMed
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Assessing the effects of hydromorphological degradation on macroinvertebrate indicators in rivers: examples, constraints, and outlook.

https://arctichealth.org/en/permalink/ahliterature89057
Source
Integr Environ Assess Manag. 2009 Jan;5(1):86-96
Publication Type
Article
Date
Jan-2009
Author
Friberg Nikolai
Sandin Leonard
Pedersen Morten L
Author Affiliation
Macaulay Land Use Research Institute, Catchment Management Group, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom. n.friberg@macaulay.ac.uk
Source
Integr Environ Assess Manag. 2009 Jan;5(1):86-96
Date
Jan-2009
Language
English
Publication Type
Article
Keywords
Animals
Conservation of Natural Resources
Ecosystem
Environmental Monitoring - methods
Geology
Invertebrates - drug effects
Rivers - chemistry
Sweden
Water Movements
Water Pollutants, Chemical - toxicity
Abstract
An extensive amount of literature on linkages between the in-stream physical environment and river benthic macroinvertebrates reports a number of relationships across multiple spatial scales. We analyzed data on different spatial scales to elucidate the linkages between different measurements of hydromorphological degradation and commonly used macroinvertebrate indices. A regression analysis of 1049 sites from 3 countries revealed that the strongest relationship between a biotic metric--average score per taxon--and physiochemical variables (R2 = 0.61) was obtained with a multiple regression model that included concentration of total phosphorus and percent arable land in the catchment, as well as hydromorphological quality variables. Analyses of 3 data sets from streams primarily affected by hydromorphological degradation showed an overall weak relationship (max R2 = 0.25) with the River Habitat Survey data of 28 Swedish streams, whereas moderate (R2 approximately 0.43) relationships with more detailed measurements of morphology were found in 2 Danish studies (39 and 6 streams, respectively). Although evidence exists in the literature on the importance of physical features for in-stream biota in general and macroinvertebrates specifically, we found only relatively weak relationships between various measures of hydromorphological stress and commonly used macroinvertebrate assessment tools. We attribute this to a combination of factors, including 1) the mixed nature of pressures acting on the majority of river reaches, 2) scaling issues (spatial and temporal) when relating habitat surveys to macroinvertebrate assessments, and 3) the scope of commonly used macroinvertebrate assessment systems (mainly focusing on water chemistry perturbation, such as eutrophication and acidification). The need is urgent to develop refined and updated biological assessment systems targeting hydromorphological stress for the use of the European Water Framework Directive (WFD) and national water-related policies.
PubMed ID
19431294 View in PubMed
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Assessing the robustness of raingardens under climate change using SDSM and temporal downscaling.

https://arctichealth.org/en/permalink/ahliterature293433
Source
Water Sci Technol. 2018 Mar; 77(5-6):1640-1650
Publication Type
Journal Article
Date
Mar-2018
Author
Erle Kristvik
Guro Heimstad Kleiven
Jardar Lohne
Tone Merete Muthanna
Author Affiliation
Department of Civil and Environmental Engineering, The Norwegian University of Science and Technology (NTNU), S. P. Andersens veg 5, 7491 Trondheim, Norway E-mail: erle.kristvik@ntnu.no.
Source
Water Sci Technol. 2018 Mar; 77(5-6):1640-1650
Date
Mar-2018
Language
English
Publication Type
Journal Article
Keywords
Cities
Climate change
Drainage, Sanitary
Floods
Norway
Rain
Time Factors
Water Movements
Abstract
Climate change is expected to lead to higher precipitation amounts and intensities causing an increase of the risk for flooding and combined sewer overflows in urban areas. To cope with these changes, water managers are requesting practical tools that can facilitate adaptive planning. This study was carried out to investigate how recent developments in downscaling techniques can be used to assess the effects of adaptive measures. A combined spatial-temporal downscaling methodology using the Statistical DownScaling Model-Decision Centric (SDSM-DC) and the Generalized Extreme Value distribution was applied to project future precipitation in the city of Bergen, Norway. A raingarden was considered a potential adaptive measure, and its performance was assessed using the RECARGA simulation tool. The benefits and limitations of using the proposed method have been demonstrated and compared to current design practices in Norway. Large differences in the raingarden's performance with respect to percentage overflow and lag-time reduction were found for varying projections. This highlights the need for working with a range of possible futures. Further, it was found that Ksat was the determining factor for peak-flow reduction and that different values of Ksat had different benefits. Engineering flexible solutions by combining measures holding different characteristics will induce robust adaptation.
PubMed ID
29595166 View in PubMed
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Assessment of potential transport of pollutants into the Barents Sea via sea ice--an observational approach.

https://arctichealth.org/en/permalink/ahliterature187977
Source
Mar Pollut Bull. 2002 Sep;44(9):861-9
Publication Type
Article
Date
Sep-2002
Author
Reinert Korsnes
Olga Pavlova
Fred Godtliebsen
Author Affiliation
Norwegian Polar Institute, Polar Environment Center, Tromsø. reinert.korsnes@ffi.no
Source
Mar Pollut Bull. 2002 Sep;44(9):861-9
Date
Sep-2002
Language
English
Publication Type
Article
Keywords
Arctic Regions
Humans
Ice
Oceans and Seas
Seasons
Water Movements
Water Pollutants
Abstract
The present estimates of ice drift in the Arctic include utilization of satellite imagery data (special sensor microwave/imager) and a reconstruction of air pressure for the period 1899-1998. A significant part of the sea ice in the Arctic Ocean has its origin in the Kara Sea and melts in the Greenland and the Barents Sea (BS). Consequently there may be a particular risk of pollutants in the Kara Sea entering the food webs of the Greenland and BS. The ice export from the Kara Sea between 1988 and 1994 was about 208,000 km2 (154 km3) per year. The import of ice into the BS was during the same period 161,000 km2 (183 km3) per year while the ice drift through the Fram Strait into the Greenland Sea was 583,000 km2 (1859 km3) per year. Ice which formed adjacent to the Ob and Yenisey rivers in early January, drifted into the BS within two years (with a probability of about 50%.
PubMed ID
12405210 View in PubMed
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Biogeography of Asterias: North Atlantic climate change and speciation.

https://arctichealth.org/en/permalink/ahliterature95952
Source
Biol Bull. 2001 Aug;201(1):95-103
Publication Type
Article
Date
Aug-2001
Author
Wares J P
Author Affiliation
Duke University Zoology, Box 90325, Durham, North Carolina 27708, USA. jpwares@unm.edu
Source
Biol Bull. 2001 Aug;201(1):95-103
Date
Aug-2001
Language
English
Publication Type
Article
Keywords
Animals
Atlantic Ocean
Climate
Echinodermata - classification - genetics - growth & development
Evolution
Geography
Phylogeny
Water Movements
Abstract
Fossil evidence suggests that the seastar genus Asterias arrived in the North Atlantic during the trans-Arctic interchange around 3.5 Ma. Previous genetic and morphological studies of the two species found in the Atlantic today suggested two possible scenarios for the speciation of A. rubens and A. forbesi. Through phylogenetic and population genetic analysis of data from a portion of the cytochrome oxidase I mitochondrial gene and a fragment of the ribosomal internal transcribed spacer region, I show that the formation of the Labrador Current 3.0 Ma was probably responsible for the initial vicariance of North Atlantic Asterias populations. Subsequent adaptive evolution in A. forbesi was then possible in isolation from the European species A. rubens. The contact zone between these two species formed recently, possibly due to a Holocene founding event of A. rubens in New England and the Canadian Maritimes.
PubMed ID
11526068 View in PubMed
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134 records – page 1 of 14.