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1.
Environ Sci Technol ; 54(5): 2734-2743, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013404

RESUMO

Organophosphate esters (OPEs) have been detected in the Arctic environment, but the influence of glacial melt on the environmental behavior of OPEs in recipient Arctic aquatic ecosystems is still unknown. In this study, water samples were collected from Lake Hazen (LH) and its tributaries to investigate the distribution of 14 OPEs in LH and to explore the input of OPEs from glacial rivers to LH and the output of OPEs from LH in 2015 and 2018. Σ14OPE concentrations in water of LH were lower than glacial rivers and its outflow, the Ruggles River. In 2015, a high melt year, we estimated that glacial rivers contributed 7.0 ± 3.2 kg OPEs to LH, compared to a 16.5 ± 0.3 kg OPEs output by the Ruggles River, suggesting that residence time and/or additional inputs via direct wet and dry deposition and permafrost melt likely result in OPE retention in the LH watershed. In 2018, a lower melt year, Σ14OPE concentrations in glacial rivers were much lower, indicating that the rate of glacier melt may govern, in part, the concentrations of OPEs in the tributaries of LH. This study highlights long-range transport of OPEs, their deposition in Arctic glaciers, landscapes, and lakes.


Assuntos
Retardadores de Chama , Regiões Árticas , Ecossistema , Monitoramento Ambiental , Ésteres , Lagos , Organofosfatos
2.
Int J Biometeorol ; 64(4): 689-699, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32006116

RESUMO

Climate oscillations affect fish population dynamics, ecological processes and fisheries activities in marine ecosystems. In the western Mediterranean, several atmospheric indices associated with pressure oscillations have been identified as the main drivers of the abundance or availability of certain resources exploited by fisheries. The main aim of this study was to explore the association between the potential effects of the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO) on the first sale price of fresh fish at the fish market of the most representative commercial species of the fisheries in the Alboran Sea (Mediterranean Sea). We used the Pearson correlation test to investigate correlations between the atmospheric oscillation indices and the fish market price of the selected species. The results suggest that inter- and intra-annual atmospheric oscillations may have an effect on bonito (Sarda sarda), European anchovy (Engraulis encrasicolus) and catsharks (Scyliorhinus spp.) abundance and catchability in the Alboran Sea and, therefore, an impact on their fish market presence and price variability according to the law of supply and demand.


Assuntos
Clima , Ecossistema , Animais , Regiões Árticas , Peixes , Mar Mediterrâneo
3.
Environ Sci Technol ; 54(5): 2780-2789, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32046488

RESUMO

Polar bears (Ursus maritimus) and ringed seals (Pusa hispida) have a strong predator-prey relationship and are facing climate-associated Arctic habitat loss and harmful dietary exposure to total mercury (THg) and other pollutants. However, little is known about whether both species inhabiting the same area exhibit similar temporal patterns in Hg concentration, niche dynamics, and body fat indices. We used THg, δ13C, and δ15N values of western Hudson Bay polar bear hair (2004-2016) and ringed seal muscle samples (2003-2015) to investigate temporal trends of these variables and multidimensional niche metrics, as well as body fat indices for both species. We found a decline in THg concentration (by 3.8% per year) and δ13C (by 1.5‰) in ringed seals suggesting a change in feeding habits and carbon source use over time, whereas no significant changes occurred in polar bears. In contrast, the polar bear 3-dimensional niche size decreased by nearly half with no change in ringed seal niche size. The δ13C spacing between both species increased by approximately 1.5× suggesting different responses to annual changes in sympagic-pelagic carbon source production. Ringed seal body fat index was higher in years of earlier sea ice breakup with no change occurring in polar bears. These findings indicate that both species are responding differently to a changing environment suggesting a possible weakening of their predator-prey relationship in western Hudson Bay.


Assuntos
Mercúrio , Focas Verdadeiras , Ursidae , Tecido Adiposo , Animais , Regiões Árticas
4.
Oecologia ; 192(3): 671-685, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32052180

RESUMO

Warming-induced nutrient enrichment in the Arctic may lead to shifts in leaf-level physiological properties and processes with potential consequences for plant community dynamics and ecosystem function. To explore the physiological responses of Arctic tundra vegetation to increasing nutrient availability, we examined how a set of leaf nutrient and physiological characteristics of eight plant species (representing four plant functional groups) respond to a gradient of experimental nitrogen (N) and phosphorus (P) enrichment. Specifically, we examined a set of chlorophyll fluorescence measures related to photosynthetic efficiency, performance and stress, and two leaf nutrient traits (leaf %C and %N), across an experimental nutrient gradient at the Arctic Long Term Ecological Research site, located in the northern foothills of the Brooks Range, Alaska. In addition, we explicitly assessed the direct relationships between chlorophyll fluorescence and leaf %N. We found significant differences in physiological and nutrient traits between species and plant functional groups, and we found that species within one functional group (deciduous shrubs) have significantly greater leaf %N at high levels of nutrient addition. In addition, we found positive, saturating relationships between leaf %N and chlorophyll fluorescence measures across all species. Our results highlight species-specific differences in leaf nutrient traits and physiology in this ecosystem. In particular, the effects of a gradient of nutrient enrichment were most prominent in deciduous plant species, the plant functional group known to be increasing in relative abundance with warming in this ecosystem.


Assuntos
Ecossistema , Tundra , Alaska , Regiões Árticas , Nutrientes
5.
Environ Sci Technol ; 54(4): 2112-2121, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31971780

RESUMO

Oil spills resulting from maritime accidents pose a poorly understood risk to the Arctic environment. We propose a novel probabilistic method to quantitatively assess these risks. Our method accounts for spatiotemporally varying population distributions, the spreading of oil, and seasonally varying species-specific exposure potential and sensitivity to oil. It quantifies risk with explicit uncertainty estimates, enables one to compare risks over large geographic areas, and produces information on a meaningful scale for decision-making. We demonstrate the method by assessing the short-term risks oil spills pose to polar bears, ringed seals, and walrus in the Kara Sea, the western part of the Northern Sea Route. The risks differ considerably between species, spatial locations, and seasons. Our results support current aspirations to ban heavy fuel oil in the Arctic but show that we should not underestimate the risks of lighter oils either, as these oils can pollute larger areas than heavier ones. Our results also highlight the importance of spatially explicit season-specific oil spill risk assessment in the Arctic and that environmental variability and the lack of data are a major source of uncertainty related to the oil spill impacts.


Assuntos
Poluição por Petróleo , Ursidae , Animais , Regiões Árticas , Ecossistema , Medição de Risco
6.
Ambio ; 49(3): 666-677, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31955396

RESUMO

Vegetation change has consequences for terrestrial ecosystem structure and functioning and may involve climate feedbacks. Hence, when monitoring ecosystem states and changes thereof, the vegetation is often a primary monitoring target. Here, we summarize current understanding of vegetation change in the High Arctic-the World's most rapidly warming region-in the context of ecosystem monitoring. To foster development of deployable monitoring strategies, we categorize different kinds of drivers (disturbances or stresses) of vegetation change either as pulse (i.e. drivers that occur as sudden and short events, though their effects may be long lasting) or press (i.e. drivers where change in conditions remains in place for a prolonged period, or slowly increases in pressure). To account for the great heterogeneity in vegetation responses to climate change and other drivers, we stress the need for increased use of ecosystem-specific conceptual models to guide monitoring and ecological studies in the Arctic. We discuss a conceptual model with three hypothesized alternative vegetation states characterized by mosses, herbaceous plants, and bare ground patches, respectively. We use moss-graminoid tundra of Svalbard as a case study to discuss the documented and potential impacts of different drivers on the possible transitions between those states. Our current understanding points to likely additive effects of herbivores and a warming climate, driving this ecosystem from a moss-dominated state with cool soils, shallow active layer and slow nutrient cycling to an ecosystem with warmer soil, deeper permafrost thaw, and faster nutrient cycling. Herbaceous-dominated vegetation and (patchy) bare ground would present two states in response to those drivers. Conceptual models are an operational tool to focus monitoring efforts towards management needs and identify the most pressing scientific questions. We promote greater use of conceptual models in conjunction with a state-and-transition framework in monitoring to ensure fit for purpose approaches. Defined expectations of the focal systems' responses to different drivers also facilitate linking local and regional monitoring efforts to international initiatives, such as the Circumpolar Biodiversity Monitoring Program.


Assuntos
Ecossistema , Tundra , Regiões Árticas , Mudança Climática , Solo , Svalbard
7.
Ambio ; 49(3): 732-748, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31955397

RESUMO

Tundra-breeding birds face diverse conservation challenges, from accelerated rates of Arctic climate change to threats associated with highly migratory life histories. Here we summarise the status and trends of Arctic terrestrial birds (88 species, 228 subspecies or distinct flyway populations) across guilds/regions, derived from published sources, raw data or, in rare cases, expert opinion. We report long-term trends in vital rates (survival, reproduction) for the handful of species and regions for which these are available. Over half of all circumpolar Arctic wader taxa are declining (51% of 91 taxa with known trends) and almost half of all waterfowl are increasing (49% of 61 taxa); these opposing trends have fostered a shift in community composition in some locations. Declines were least prevalent in the African-Eurasian Flyway (29%), but similarly prevalent in the remaining three global flyways (44-54%). Widespread, and in some cases accelerating, declines underscore the urgent conservation needs faced by many Arctic terrestrial bird species.


Assuntos
Aves , Tundra , Animais , Regiões Árticas , Mudança Climática , Reprodução
8.
Ambio ; 49(3): 655-665, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31955398

RESUMO

The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.


Assuntos
Ecossistema , Monitoramento Ambiental , Regiões Árticas , Biodiversidade
9.
Ambio ; 49(3): 833-847, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31955399

RESUMO

This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to inform the State of the Arctic Terrestrial Biodiversity Report developed by the Circumpolar Biodiversity Monitoring Program (CBMP) of the Conservation of Arctic Flora and Fauna (CAFF), Arctic Council working group. Salient points about the status and trends of Arctic biodiversity and biodiversity monitoring are organized by taxonomic groups: (1) vegetation, (2) invertebrates, (3) mammals, and (4) birds. This is followed by a discussion about commonalities across the collection of papers, for example, that heterogeneity was a predominant pattern of change particularly when assessing global trends for Arctic terrestrial biodiversity. Finally, the need for a comprehensive, integrated, ecosystem-based monitoring program, coupled with targeted research projects deciphering causal patterns, is discussed.


Assuntos
Biodiversidade , Ecossistema , Animais , Regiões Árticas , Aves , Invertebrados
10.
Glob Chang Biol ; 26(3): 1908-1925, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31957145

RESUMO

Warming occurs in the Arctic twice as fast as the global average, which in turn leads to a large enhancement in terpenoid emissions from vegetation. Volatile terpenoids are the main class of biogenic volatile organic compounds (VOCs) that play crucial roles in atmospheric chemistry and climate. However, the biochemical mechanisms behind the temperature-dependent increase in VOC emissions from subarctic ecosystems are largely unexplored. Using 13 CO2 -labeling, we studied the origin of VOCs and the carbon (C) allocation under global warming in the soil-plant-atmosphere system of contrasting subarctic heath tundra vegetation communities characterized by dwarf shrubs of the genera Salix or Betula. The projected temperature rise of the subarctic summer by 5°C was realistically simulated in sophisticated climate chambers. VOC emissions strongly depended on the plant species composition of the heath tundra. Warming caused increased VOC emissions and significant changes in the pattern of volatiles toward more reactive hydrocarbons. The 13 C was incorporated to varying degrees in different monoterpene and sesquiterpene isomers. We found that de novo monoterpene biosynthesis contributed to 40%-44% (Salix) and 60%-68% (Betula) of total monoterpene emissions under the current climate, and that warming increased the contribution to 50%-58% (Salix) and 87%-95% (Betula). Analyses of above- and belowground 12/13 C showed shifts of C allocation in the plant-soil systems and negative effects of warming on C sequestration by lowering net ecosystem exchange of CO2 and increasing C loss as VOCs. This comprehensive analysis provides the scientific basis for mechanistically understanding the processes controlling terpenoid emissions, required for modeling VOC emissions from terrestrial ecosystems and predicting the future chemistry of the arctic atmosphere. By changing the chemical composition and loads of VOCs into the atmosphere, the current data indicate that global warming in the Arctic may have implications for regional and global climate and for the delicate tundra ecosystems.


Assuntos
Aquecimento Global , Compostos Orgânicos Voláteis , Regiões Árticas , Ecossistema , Tundra
11.
Environ Sci Process Impacts ; 22(1): 207-216, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31894800

RESUMO

Scientists and decision makers need accurate, accessible and fast tools to assess and prioritize the persistence (POV) and environmental long-range transport potential (LRTP) of chemicals. Here we evaluated the Organisation for Economic Co-operation and Development (OECD) POV and LRTP Screening Tool ("the Tool") with respect to the POV and LRTP estimates that the Tool provides for organophosphate esters (OPEs). We found that the use of default parameter values could significantly underestimate POV and LRTP values of OPEs and, potentially, other Persistent Mobile Organic Compounds (PMOCs), by not accounting for episodic atmospheric transport and poleward river-based transport in the northern hemisphere. Specifically, sensitivity and Monte Carlo uncertainty analyses indicate that non-chlorinated OPEs could be subject to LRTP when uncertainties in gas-particle partitioning and its implications for atmospheric degradation are considered, and chlorinated OPEs when river-based transport is considered. Further, the analyses showed strong dependence of results on the accuracy of the environmental half-lives used as input parameters. We suggest that the Tool could be modified to include an optional "Arctic (PMOC) LRTP setting" that incorporates episodic atmospheric and river-based transport as well as decreased environmental half-lives due to cold temperatures.


Assuntos
Poluentes Ambientais , Organização para a Cooperação e Desenvolvimento Econômico , Organofosfatos , Regiões Árticas , Monitoramento Ambiental , Poluentes Ambientais/análise , Ésteres , Organofosfatos/análise
12.
Environ Sci Process Impacts ; 22(2): 285-293, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942888

RESUMO

Perfluorocarboxylic acids (PFCAs) are environmental contaminants that are highly persistent, and many are bio-accumulative and have been detected along with their atmospheric precursors far from emission sources. The overall importance of precursor emissions as an indirect source of PFCAs to the environment is uncertain. Previous studies have estimated the atmospheric source of PFCAs using models and degradation pathways of differing complexities, leading to quantitatively different results. We present results from simulations of atmospheric PFCA formation and fate using the chemical transport model GEOS-Chem. We simulate the most up-to-date chemistry available to our knowledge for the degradation of the precursors fluorotelomer alcohol (FTOH), fluorotelomer olefin (FTO), and fluorotelomer iodide (FTI), as well as the deposition and transport of the precursors, intermediates and end-products of the formation chemistry. We calculate yields of C3-C13 PFCAs formed from 4 : 2 to 12 : 2 fluorotelomer precursors and their deposition to the surface. We find that the ratio of long-chain to short-chain PFCAs increases strongly with distance from source regions. We compare our model results to remote deposition measurements and mid-latitude rainwater measurements. The model captures the observed relationship between rainwater abundance and PFCA chain length, as well as the average deposition rates at mid-latitude and Arctic sites, but underestimates the deposition of PFDoA, PFDA, and TFA at mid-latitudes and PFNA at the Devon Ice Cap. We provide estimates of cumulative PFCA deposition globally. We find that given the most recent emission inventory, the atmospheric source of PFCAs is 6-185 tonnes per year globally and 0.1-2.1 tonnes per year to the Arctic.


Assuntos
Fluorcarbonetos , Modelos Químicos , Movimentos do Ar , Regiões Árticas , Ácidos Carboxílicos
13.
Environ Pollut ; 256: 113389, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31685327

RESUMO

The boreoatlantic gonate squid (Gonatus fabricii) represents important prey for top predators-such as marine mammals, seabirds and fish-and is also an efficient predator of crustaceans and fish. Gonatus fabricii is the most abundant cephalopod in the northern Atlantic and Arctic Ocean but the trace element accumulation of this ecologically important species is unknown. In this study, trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) were analysed from the mantle muscle and the digestive gland tissue of juveniles, adult females, and adult males that were captured south of Disko Island off West-Greenland. To assess the feeding habitat and trophic position of this species, stable isotopes of carbon (δ13C) and nitrogen (δ15N) were measured in their muscle tissue. Mercury concentrations were positively correlated with size (mantle length) and trophic position. The Hg/Se ratio was assessed because Se has been suggested to play a protective role against Hg toxicity and showed a molar surplus of Se relative to Hg. Cadmium concentrations in the digestive gland were negatively correlated with size and trophic position (δ15N), which suggested a dietary shift from Cd-rich crustaceans towards Cd-poor fish during ontogeny. This study provides trace element concentration data for G. fabricii from Greenlandic waters, which represents baseline data for a northern cephalopod species. Within West-Greenland waters, G. fabricii appears to be an important vector for the transfer of Cd in the Arctic pelagic food web.


Assuntos
Bioacumulação , Decapodiformes/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Regiões Árticas , Oceano Atlântico , Clima Frio , Ecossistema , Feminino , Cadeia Alimentar , Masculino , Metais Pesados/metabolismo , Alimentos Marinhos/análise , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
14.
Environ Pollut ; 256: 113386, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31706761

RESUMO

After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, radionuclides released by this event were observed in the Pacific Ocean. Models predicted that these radionuclides would be transported to the Bering Sea; however, limited evidence currently reveals the transportation of these radionuclides to the Arctic Ocean. Here, we provide the first direct observation showing that FDNPP-derived 134Cs and 137Cs were present in subarctic regions and the Arctic Ocean (Chukchi Sea) in 2017. Furthermore, we conclude that these radionuclides were transported from the Pacific Ocean into the Bering and Chukchi Seas by ocean currents. Additionally, the 137Cs activity concentrations in the Bering Sea exceed those in all previous reports. Due to the continuous leaking of radionuclides from the FDNPP, we hypothesize that FDNPP-derived radionuclides will be continuously transported to the Arctic Ocean in the next several years. Our results suggest that though far away from Fukushima, the accident-derived anthropogenic radionuclides also influenced the Arctic Ocean by ocean currents.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Monitoramento de Radiação/métodos , Poluentes Radioativos da Água/análise , Regiões Árticas , Japão , Centrais Nucleares , Oceanos e Mares , Oceano Pacífico
15.
Ambio ; 49(3): 693-703, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31792797

RESUMO

We present a comprehensive list of non-native vascular plants known from the Arctic, explore their geographic distribution, analyze the extent of naturalization and invasion among 23 subregions of the Arctic, and examine pathways of introductions. The presence of 341 non-native taxa in the Arctic was confirmed, of which 188 are naturalized in at least one of the 23 regions. A small number of taxa (11) are considered invasive; these plants are known from just three regions. In several Arctic regions there are no naturalized non-native taxa recorded and the majority of Arctic regions have a low number of naturalized taxa. Analyses of the non-native vascular plant flora identified two main biogeographic clusters within the Arctic: American and Asiatic. Among all pathways, seed contamination and transport by vehicles have contributed the most to non-native plant introduction in the Arctic.


Assuntos
Espécies Introduzidas , Plantas , Regiões Árticas
16.
Int J Syst Evol Microbiol ; 70(1): 569-575, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31647406

RESUMO

Four strains of bacteria designated as AR-3-6T, AT-3-1, AR-3-8T and AR-3-15 were isolated from Arctic soil. Cells were aerobic, Gram-staining-negative, non-motile, non-spore-forming, rod-shaped and yellow-pigmented. Flexirubin-type pigments were present in all strains. All strains tolerated 2 % of NaCl and were psychrotolerant. A phylogenetic analysis based on its 16S rRNA gene sequence revealed that these strains formed a lineage within the family Cytophagaceae that were distinct from various members of the genus Dyadobacter. The closest member of strain AR-3-6T was D. koreensis DSM 19938T (97.2 % sequence similarity) and AR-3-8T was D. hamtensis HHS 11T (97.9 %). The predominant respiratory quinone was menaqinone-7. The major polar lipid was phosphatidylethanolamine. The major cellular fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0, C16 : 1ω5c and iso-C17 : 0 3-OH. The DNA G+C content of strains ranges from 40.1 to 42.1 mol%. On the basis of phenotypic, genotypic, chemotaxonomic and phylogenetic analysis, both strains AR-3-6T and AR-3-8T represent a novel member in the genus Dyadobacter, for which the name Dyadobacter psychrotolerans sp. nov. and Dyadobacter frigoris sp. nov. are proposed, respectively. The type strain of Dyadobacter psychrotolerans is AR-3-6T (=KEMB 9005-743T=KACC 21172T=NBRC 113790T) and type strain of Dyadobacter frigoris is AR-3-8T (=KEMB 9005-744T= KACC 21173T=NBRC 113791T).


Assuntos
Cytophagaceae/classificação , Filogenia , Microbiologia do Solo , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfatidiletanolaminas/química , Pigmentação , Polienos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Int J Syst Evol Microbiol ; 70(1): 44-50, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31513007

RESUMO

A novel psychrophilic, light-yellow-coloured, aerobic, Gram-stain-negative, rod-shaped, non-motile bacterium, designated strain AR-3-4T was isolated from a sample of Arctic soil. Strain AR-3-4T grew at 0-25 °C, pH 6.0-9.0 and 0-1.0 % (w/v) NaCl concentration. The 16S rRNA gene sequence analysis showed that strain AR-3-4T belonged to the genus Flavobacterium, with nearest phylogenetic neighbour being Flavobacterium fluvii H7T (97.5 % sequence similarity). The strain comprised phosphatidylethanolamine as the main polar lipid, MK-6 as predominant respiratory quinone, and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), anteiso-C15 : 0 and iso-C15 : 0 as the major fatty acids. The average nucleotide identity and in silico DNA-DNA hybridization values between strain AR-3-4T and closest members were below the threshold values of 95 % and 70 %, respectively. The DNA G+C content was 33.0 mol%. Based on the polyphasic taxonomic data, the novel species Flavobacterium cellulosilyticum sp. nov. is proposed with the type strain AR-3-4T (=KEMB 9005-740T=KACC 21171T=NBRC 113787T).


Assuntos
Flavobacterium/classificação , Filogenia , Microbiologia do Solo , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
Ambio ; 49(2): 407-418, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31236784

RESUMO

The scientific literature on physical changes in the Arctic region driven by climate change is extensive. In addition, the emerging understanding of physical feedbacks and teleconnections between the Arctic and the rest of the world suggests that the warming in the Arctic region is likely to cause impacts that extend well beyond the region itself. However, there is only limited research on how Arctic change may affect economies and individual industry sectors around the world. We argue that there is a pressing need for more research on this topic and present a conceptual framework to guide future research for assessing the regional and global economic impacts of Arctic change, including both possible benefits and costs. We stress on the importance of a transdisciplinary approach, which includes an integration of the natural sciences, economics and social sciences, as well as engagement with a wide range of stakeholders to better understand and manage the implications of Arctic change.


Assuntos
Mudança Climática , Regiões Árticas
19.
Ambio ; 49(3): 786-800, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31332767

RESUMO

Lemmings are a key component of tundra food webs and changes in their dynamics can affect the whole ecosystem. We present a comprehensive overview of lemming monitoring and research activities, and assess recent trends in lemming abundance across the circumpolar Arctic. Since 2000, lemmings have been monitored at 49 sites of which 38 are still active. The sites were not evenly distributed with notably Russia and high Arctic Canada underrepresented. Abundance was monitored at all sites, but methods and levels of precision varied greatly. Other important attributes such as health, genetic diversity and potential drivers of population change, were often not monitored. There was no evidence that lemming populations were decreasing in general, although a negative trend was detected for low arctic populations sympatric with voles. To keep the pace of arctic change, we recommend maintaining long-term programmes while harmonizing methods, improving spatial coverage and integrating an ecosystem perspective.


Assuntos
Arvicolinae , Ecossistema , Animais , Regiões Árticas , Canadá , Dinâmica Populacional , Federação Russa
20.
Ambio ; 49(3): 704-717, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31030417

RESUMO

The terrestrial chapter of the Circumpolar Biodiversity Monitoring Programme (CBMP) has the potential to bring international multi-taxon, long-term monitoring together, but detailed fundamental species information for Arctic arthropods lags far behind that for vertebrates and plants. In this paper, we demonstrate this major challenge to the CBMP by focussing on spiders (Order: Araneae) as an example group. We collate available circumpolar data on the distribution of spiders and highlight the current monitoring opportunities and identify the key knowledge gaps to address before monitoring can become efficient. We found spider data to be more complete than data for other taxa, but still variable in quality and availability between Arctic regions, highlighting the need for greater international co-operation for baseline studies and data sharing. There is also a dearth of long-term datasets for spiders and other arthropod groups from which to assess status and trends of biodiversity. Therefore, baseline studies should be conducted at all monitoring stations and we make recommendations for the development of the CBMP in relation to terrestrial arthropods more generally.


Assuntos
Artrópodes , Aranhas , Animais , Regiões Árticas , Biodiversidade , Estudos Longitudinais
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