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1.
Glob Chang Biol ; 30(6): e17352, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822670

RESUMO

The Arctic is the fastest-warming region on the planet, and the lengthening ice-free season is opening Arctic waters to sub-Arctic species such as the killer whale (Orcinus orca). As apex predators, killer whales can cause significant ecosystem-scale changes. Setting conservation priorities for killer whales and their Arctic prey species requires knowledge of their evolutionary history and demographic trajectory. Using whole-genome resequencing of 24 killer whales sampled in the northwest Atlantic, we first explored the population structure and demographic history of Arctic killer whales. To better understand the broader geographic relationship of these Arctic killer whales to other populations, we compared them to a globally sampled dataset. Finally, we assessed threats to Arctic killer whales due to anthropogenic harvest by reviewing the peer-reviewed and gray literature. We found that there are two highly genetically distinct, non-interbreeding populations of killer whales using the eastern Canadian Arctic. These populations appear to be as genetically different from each other as are ecotypes described elsewhere in the killer whale range; however, our data cannot speak to ecological differences between these populations. One population is newly identified as globally genetically distinct, and the second is genetically similar to individuals sampled from Greenland. The effective sizes of both populations recently declined, and both appear vulnerable to inbreeding and reduced adaptive potential. Our survey of human-caused mortalities suggests that harvest poses an ongoing threat to both populations. The dynamic Arctic environment complicates conservation and management efforts, with killer whales adding top-down pressure on Arctic food webs crucial to northern communities' social and economic well-being. While killer whales represent a conservation priority, they also complicate decisions surrounding wildlife conservation and resource management in the Arctic amid the effects of climate change.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Orca , Animais , Orca/fisiologia , Regiões Árticas , Espécies em Perigo de Extinção , Canadá
2.
Glob Chang Biol ; 30(6): e17353, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38837850

RESUMO

Rapid climate change is altering Arctic ecosystems at unprecedented rates. These changes in the physical environment may open new corridors for species range expansions, with substantial implications for subsistence-dependent communities and sensitive ecosystems. Over the past 20 years, rising incidental harvest of Pacific salmon by subsistence fishers has been monitored across a widening range spanning multiple land claim jurisdictions in Arctic Canada. In this study, we connect Indigenous and scientific knowledges to explore potential oceanographic mechanisms facilitating this ongoing northward expansion of Pacific salmon into the western Canadian Arctic. A regression analysis was used to reveal and characterize a two-part mechanism related to thermal and sea-ice conditions in the Chukchi and Beaufort seas that explains nearly all of the variation in the relative abundance of salmon observed within this region. The results indicate that warmer late-spring temperatures in a Chukchi Sea watch-zone and persistent, suitable summer thermal conditions in a Beaufort Sea watch-zone together create a range-expansion corridor and are associated with higher salmon occurrences in subsistence harvests. Furthermore, there is a body of knowledge to suggest that these conditions, and consequently the presence and abundance of Pacific salmon, will become more persistent in the coming decades. Our collaborative approach positions us to document, explore, and explain mechanisms driving changes in fish biodiversity that have the potential to, or are already affecting, Indigenous rights-holders in a rapidly warming Arctic.


Assuntos
Mudança Climática , Animais , Regiões Árticas , Canadá , Salmão/fisiologia , Temperatura , Distribuição Animal , Ecossistema , Estações do Ano
4.
Glob Health Action ; 17(1): 2354008, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38828500

RESUMO

BACKGROUND: Postpartum depression (PPD) affects approximately 17% of the women worldwide with nearly half of all cases going undetected. More research on maternal mental health, particularly among healthcare professionals and pregnant mothers, could help identify PPD risks and reduce its prevalence. OBJECTIVE: Given that awareness of PPD is a crucial preventive factor, we studied PPD awareness among midwives and pregnant women in Arkhangelsk, Arctic Russia. METHODS: A qualitative study was conducted using in-depth semi-structured interviews. Midwives and pregnant women were recruited from the women's clinic of the Arkhangelsk municipal polyclinic. Seven midwives and 12 pregnant mothers were interviewed. RESULTS: Midwives described limited time for psychological counselling of pregnant women; they reported that their primary focus was on the physiological well-being of women. Pregnant women have expressed a desire for their families to share responsibilities. The participants considered PPD as a mix of psychological and physiological symptoms, and they also highlighted a discrepancy between the expectations of pregnant women and the reality of motherhood. The present study underscored the limited understanding of PPD identification. CONCLUSIONS: The findings suggest that there is a need for increased awareness among midwives and pregnant women regarding PPD. Prevention programs targeting PPD with a specific emphasis on enhancing maternal mental health knowledge are warranted.


Main findings: Pregnant women and midwives in an Arctic Russian setting have low awareness of postpartum depression.Added knowledge: Improved awareness among pregnant women and midwives about the mental health of women after childbirth, educating pregnant women about symptoms of postpartum depression, encourage them to express their needs and collaboration with family supporters may help to reduce postpartum depression burden.Global health impact for policy and action: Updated campaigns and prevention programs with the focus on increasing the knowledge on mental health among pregnant women and health personnel may be effective support for Primary health care.


Assuntos
Depressão Pós-Parto , Conhecimentos, Atitudes e Prática em Saúde , Tocologia , Pesquisa Qualitativa , Humanos , Feminino , Depressão Pós-Parto/psicologia , Depressão Pós-Parto/epidemiologia , Gravidez , Federação Russa , Adulto , Gestantes/psicologia , Regiões Árticas , Entrevistas como Assunto , Adulto Jovem
5.
Glob Chang Biol ; 30(5): e17273, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38727723

RESUMO

Rapid warming at high latitudes triggers poleward shifts of species' distributions that impact marine biodiversity. In the open sea, the documented redistributions of fish lead to a borealization of Arctic fauna. A climate-driven borealization and increased species diversity at high latitudes are also expected in coastal fish communities, but they have not been previously documented on a large, biogeographic scale. Here, we investigate the impact of temperature change over the last 25 years on fish communities along the coast of Norway. The study area, spanning different ecoclimatic zones between 62° and 71° N, harbors over 200 species of boreal and Arctic fish. Several of these fish species are harvested by coastal and indigenous communities, influencing settlement geography and livelihood. The long-term data on coastal water temperatures and fish species were obtained from monitoring stations and scientific surveys. Water temperature measured at three fixed sampling stations distributed along the coast show increased temperatures during the study period. The fish species distribution and abundance data were obtained from the annually standardized scientific bottom trawl survey program. Fish species richness, which was highest in the south, increased with warming first in the south and then, gradually, further north, eventually affecting biodiversity in the whole study area. Fish community composition showed a distinct latitudinal pattern early in the study, with Arctic fish species confined to the north and boreal species dominating the south. The poleward shifts eventually eroded this zoogeographic pattern, resulting in more boreal fish species in the north and an increased homogenization of species composition along the Norwegian coast. The climate-driven reorganization of fish communities affects coastal ecosystems that are exposed to fisheries, aquaculture, and other rapidly expanding human activities, stressing the urgent need for a climate adaptation of integrated coastal management.


Assuntos
Biodiversidade , Mudança Climática , Peixes , Temperatura , Animais , Peixes/fisiologia , Noruega , Regiões Árticas
6.
Sci Adv ; 10(20): eadl5904, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758795

RESUMO

Marine heatwaves are increasing in frequency and intensity as climate change progresses, especially in the highly productive Arctic regions. Although their effects on primary producers will largely determine the impacts on ecosystem services, mechanistic understanding on phytoplankton responses to these extreme events is still very limited. We experimentally exposed Arctic phytoplankton assemblages to stable warming, as well as to repeated heatwaves, and measured temporally resolved productivity, physiology, and composition. Our results show that even extreme stable warming increases productivity, while the response to heatwaves depends on the specific scenario applied and is not predictable from stable warming responses. This appears to be largely due to the underestimated impact of the cool phase following a heatwave, which can be at least as important as the warm phase for the overall response. We show that physiological and compositional adjustments to both warm and cool phases drive overall phytoplankton productivity and need to be considered mechanistically to predict overall ecosystem impacts.


Assuntos
Mudança Climática , Ecossistema , Fitoplâncton , Fitoplâncton/fisiologia , Regiões Árticas , Temperatura Alta , Aquecimento Global
7.
Environ Microbiol ; 26(5): e16640, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38775217

RESUMO

Increased temperatures in Arctic tundra ecosystems are leading to higher microbial respiration rates of soil organic matter, resulting in the release of carbon dioxide and methane. To understand the effects of this microbial activity, it is important to better characterize the diverse microbial communities in Arctic soil. Our goal is to refine our understanding of the phylogenetic diversity of Terriglobia, a common but elusive group within the Acidobacteriota phylum. This will help us link this diversity to variations in carbon and nitrogen usage patterns. We used long-read Oxford Nanopore MinION sequences in combination with metagenomic short-read sequences to assemble complete Acidobacteriota genomes. This allowed us to build multi-locus phylogenies and annotate pangenome markers to distinguish Acidobacteriota strains from several tundra soil isolates. We identified a phylogenetic cluster containing four new species previously associated with Edaphobacter lichenicola. We conclude that this cluster represents a new genus, which we have named Tunturibacter. We describe four new species: Tunturibacter lichenicola comb. nov., Tunturibacter empetritectus sp. nov., Tunturibacter gelidoferens sp. nov., and Tunturibacter psychrotolerans sp. nov. By uncovering new species and strains within the Terriglobia and improving the accuracy of their phylogenetic placements, we hope to enhance our understanding of this complex phylum and shed light on the mechanisms that shape microbial communities in polar soils.


Assuntos
Genoma Bacteriano , Filogenia , Microbiologia do Solo , Tundra , Acidobacteria/genética , Acidobacteria/classificação , Acidobacteria/isolamento & purificação , RNA Ribossômico 16S/genética , Regiões Árticas
8.
Parasite ; 31: 26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38775717

RESUMO

Several studies have shown that the euryxenic trematode Derogenes varicus (Müller, 1784) represents a species complex. Four lineages have been designated (DV1-4) with the DV1 clade corresponding to D. varicus sensu stricto. Herein, we investigate newly collected specimens of D. varicus sensu lato from Scandinavian and Arctic waters using integrative taxonomy. The trematodes were collected from Melanogrammus aeglefinus, Eutrigla gurnardus, Trachinus draco, and Merluccius merluccius off the Atlantic coast of Sweden and from Hippoglossoides platessoides from Arctic Svalbard. 28S sequences of derogenids from Sweden were identical to D. varicus sensu stricto, confirming its euryxeny. The 28S sequences of Derogenes sp. from H. platessoides were identical to Derogenes DV2 and differed from D. varicus sensu stricto by 3% and from Derogenes DV3 by 2%. The 28S sequence divergences of Derogenes sp. from H. platessoides with D. ruber and D. lacustris were 3 and 10%, respectively. ITS2 and cox1 divergences between Derogenes sp. from H. platessoides and other Derogenes species/lineages were at levels of interspecific differences. The species from H. platessoides is described here as D. abba n. sp. We also examined the type material of Progonus muelleri (Levinsen, 1881), the type and only species of the genus Progonus, with redescription and designations of paralectotypes. Based on specimens from Theodor Odhner's collections at the Swedish Museum of Natural History, SMNH, Stockholm, we provide novel morphological and anatomical data for D. varicus sensu lato species complex. Lastly, we investigated Arthur Looss's "lost collection" of Trematodes at the SMNH and characterised a putative species Derogenes sp. "limula".


Title: Démêler le complexe d'espèces Derogenes varicus dans les eaux scandinaves et arctiques : description de Derogenes abba n. sp. (Trematoda, Derogenidae) parasite d'Hippoglossoides platessoides et nouveaux signalements d'hôtes pour D. varicus (Müller, 1784) sensu stricto. Abstract: Plusieurs études ont montré que le trématode euryxene Derogenes varicus (Müller, 1784) représente un complexe d'espèces. Quatre lignées ont été désignées (DV1­4), le clade DV1 correspondant à D. varicus sensu stricto. Ici, nous étudions des spécimens nouvellement collectés de D. varicus sensu lato dans les eaux scandinaves et arctiques en utilisant la taxonomie intégrative. Les trématodes ont été collectés de Melanogrammus aeglefinus, Eutrigla gurnardus, Trachinus draco et Merluccius merluccius au large de la côte atlantique de la Suède et d'Hippoglossoides platessoides du Svalbard arctique. Les séquences 28S des Derogenidae de Suède étaient identiques à D. varicus sensu stricto, confirmant son euryxénie. Les séquences 28S de Derogenes sp. de H. platessoides étaient identiques à Derogenes DV2 et différaient de D. varicus sensu stricto par 3% et de Derogenes DV3 par 2%. Les divergences des séquence 28S de Derogenes sp. de H. platessoides avec D. ruber et D. lacustris étaient respectivement de 3 et 10%. Les divergences ITS2 et cox1 entre Derogenes sp. de H. platessoides et d'autres espèces/lignées de Derogenes se situaient à des niveaux de différences interspécifiques. L'espèce de H. platessoides est décrite ici comme Derogenes abba n. sp. Nous avons également examiné le matériel type de Progonus muelleri (Levinsen, 1881), type et seule espèce du genre Progonus, avec une redescription et des désignations de paralectotypes. Sur la base de spécimens des collections de Theodor Odhner au Musée suédois d'histoire naturelle (SMNH), Stockholm, nous fournissons de nouvelles données morphologiques et anatomiques sur le complexe d'espèces de D. varicus sensu lato. Enfin, nous avons étudié la « collection perdue ¼ de Trématodes d'Arthur Looss au SMNH et caractérisé une espèce putative, Derogenes sp. « limula ¼.


Assuntos
Filogenia , Trematódeos , Infecções por Trematódeos , Animais , Trematódeos/classificação , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação , Trematódeos/genética , Regiões Árticas , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Suécia , Doenças dos Peixes/parasitologia , RNA Ribossômico 28S/genética , Gadiformes/parasitologia , Svalbard , DNA de Helmintos
9.
Artigo em Inglês | MEDLINE | ID: mdl-38780584

RESUMO

Four yeast strains belonging to the basidiomycetous yeast genus Mrakia were isolated from diverse habitats in the Ny-Ålesund region (Svalbard, High Arctic): two from vascular plants, one from seawater and one from freshwater. Phylogenetic analysis, based on the ITS region and the D1/D2 domain of the 28S rRNA gene, identified these four strains as representing two novel species within the genus Mrakia. The names Mrakia polaris sp. nov. (MycoBank number: MB 852063) and Mrakia amundsenii sp. nov. (MycoBank number: MB 852064) are proposed. These two new species show distinct psychrophilic adaptations, as they exhibit optimal growth at temperatures between 10 and 15°C, while being unable to grow at 25°C. The holotype of M. polaris sp. nov. is CPCC 300345T, and the holotype of M. amundsenii sp. nov. is CPCC 300572T.


Assuntos
DNA Fúngico , Filogenia , Água do Mar , Análise de Sequência de DNA , Regiões Árticas , DNA Fúngico/genética , Água do Mar/microbiologia , Técnicas de Tipagem Micológica , Svalbard , RNA Ribossômico 28S/genética , Basidiomycota/genética , Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Água Doce/microbiologia , Ecossistema , Temperatura Baixa , Saccharomycetales/classificação , Saccharomycetales/genética , Saccharomycetales/isolamento & purificação
10.
BMC Health Serv Res ; 24(1): 656, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778349

RESUMO

BACKGROUND: An increasingly complex healthcare system entails an urgent need for competent and resilient leadership. However, there is a lack of extensive research on leadership development within healthcare. The knowledge gaps extend to various frameworks and contexts, particularly concerning municipal healthcare, knowledge leadership, and the application of knowledge in the field of practice. This study is the first in a larger action research project that aims to co-create a knowledge-based continuous leadership development program for healthcare in a rural Arctic municipality. This present study aims to explore the knowledge and experiences of the participating healthcare leaders to develop a common basis for co-creating the program. METHODS: This hermeneutical study presents the first cycle of the larger action research project. An appreciative approach facilitated the project. Twenty-three healthcare leaders from three different leadership levels attended and evaluated two leadership development workshops and participated in four focus groups. The data were analyzed using Braun and Clarke's reflexive thematic analysis. RESULTS: Two main themes were identified: (1) changing from striving solo players to team players, and (2) learning to handle a conflicting and complex context. These results influenced how the leadership development program based on the participants' co-creation was organized as a collective and relational process rather than an individual competence replenishment. CONCLUSIONS: The knowledge and experiences of healthcare leaders led to the co-creation of a knowledge-based continuous leadership development program based on the facilitated interaction of four essential elements: (1) competence development, (2) structures for interaction, (3) interpersonal safety, and (4) collective values and goals. The interaction was generated through trusted reflection facilitated by appreciative inquiry. The four elements and core played a crucial role in fostering relationships and facilitating learning, driving transformative change in this leadership development program. The study's results provide a solid foundation for further co-creating the program. However, more research is needed to fully explore the practical application and overall significance.


Assuntos
Grupos Focais , Pesquisa sobre Serviços de Saúde , Liderança , Serviços de Saúde Rural , Humanos , Serviços de Saúde Rural/organização & administração , Feminino , Regiões Árticas , Masculino , Desenvolvimento de Pessoal , Desenvolvimento de Programas , Adulto , Pessoa de Meia-Idade , Pesquisa Qualitativa
11.
Int J Circumpolar Health ; 83(1): 2359161, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38785137

RESUMO

A food assessment questionnaire was completed by Alutiiq and Eyak peoples of the Chugach Region of Alaska in 2016-2017. This questionnaire, conducted by the Chugach Regional Resource Commission, gathered 87 responses from adults residing in seven communities. The questions related to traditional food systems, food security, and food sovereignty and were organised into six sections: Community Food Resources, Diet and Health, Culture, Organisation and Governance, Food Resources, and Natural Resources and Environment. Nine questions directly addressed food sovereignty. Results revealed the importance of traditional food sources in the communities, foods that are not readily available or are difficult to access, resources that are useful to improve traditional food security, health problems that are perceived to be caused or exacerbated by the lack of traditional foods in the area, traditional foods commonly consumed, and barriers from accessing traditional foods. Additionally, recommendations for improving food systems and addressing barriers are provided.


Assuntos
Segurança Alimentar , Abastecimento de Alimentos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alaska , Nativos do Alasca , Regiões Árticas , Dieta , Inquéritos e Questionários
12.
Int J Circumpolar Health ; 83(1): 2349330, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38726478

RESUMO

Stress-related illness is a common and increasing cause for sick leave in Sweden. Spending time in nature reduces stress and promotes health and well-being. Accordingly, nature-based interventions (NBI) for people with stress-related illness have been developed and implemented in southern Scandinavia; however, such interventions are uncommon in the Circumpolar North. Previous studies have examined the effects and experiences of participating in NBI, but research about different stakeholders' perspectives on NBI is lacking. The aim of this study was to explore different key stakeholders' perceptions of the value of NBI in promoting health in people with stress-related illness. Data were collected through semi-structured interviews with 11 persons with stress-related illness experience, 14 healthcare professionals, and 11 entrepreneurs offering NBI. Qualitative content analysis resulted in four categories: Providing opportunity for recovery, Offering new perspectives and opportunity for reflection, Empowering balance and control in life, and Enabling one to overcome barriers. Although the study was conducted in a region where NBI is not widely implemented, the different stakeholders expressed similar perceptions of the value of NBI, indicating that NBI may be a valuable complement to health care which reaches people with stress-related illness needs and promotes their health.


Assuntos
Promoção da Saúde , Pesquisa Qualitativa , Estresse Psicológico , Humanos , Suécia , Masculino , Feminino , Promoção da Saúde/organização & administração , Adulto , Pessoa de Meia-Idade , Entrevistas como Assunto , Natureza , Regiões Árticas , Pessoal de Saúde/psicologia
13.
Environ Sci Technol ; 58(19): 8490-8500, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696308

RESUMO

Persistent organic pollutants (POPs) tend to accumulate in cold regions by cold condensation and global distillation. Soil organic matter is the main storage compartment for POPs in terrestrial ecosystems due to deposition and repeated air-surface exchange processes. Here, physicochemical properties and environmental factors were investigated for their role in influencing POPs accumulation in soils of the Tibetan Plateau and Antarctic and Arctic regions. The results showed that the soil burden of most POPs was closely coupled to stable mineral-associated organic carbon (MAOC). Combining the proportion of MAOC and physicochemical properties can explain much of the soil distribution characteristics of the POPs. The background levels of POPs were estimated in conjunction with the global soil database. It led to the proposition that the stable soil carbon pools are key controlling factors affecting the ultimate global distribution of POPs, so that the dynamic cycling of soil carbon acts to counteract the cold-trapping effects. In the future, soil carbon pool composition should be fully considered in a multimedia environmental model of POPs, and the risk of secondary release of POPs in soils under conditions such as climate change can be further assessed with soil organic carbon models.


Assuntos
Carbono , Poluentes do Solo , Solo , Solo/química , Poluentes Orgânicos Persistentes , Monitoramento Ambiental , Regiões Árticas , Ecossistema
14.
Proc Natl Acad Sci U S A ; 121(21): e2315513121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739784

RESUMO

Mercury (Hg) is a heterogeneously distributed toxicant affecting wildlife and human health. Yet, the spatial distribution of Hg remains poorly documented, especially in food webs, even though this knowledge is essential to assess large-scale risk of toxicity for the biota and human populations. Here, we used seabirds to assess, at an unprecedented population and geographic magnitude and high resolution, the spatial distribution of Hg in North Atlantic marine food webs. To this end, we combined tracking data of 837 seabirds from seven different species and 27 breeding colonies located across the North Atlantic and Atlantic Arctic together with Hg analyses in feathers representing individual seabird contamination based on their winter distribution. Our results highlight an east-west gradient in Hg concentrations with hot spots around southern Greenland and the east coast of Canada and a cold spot in the Barents and Kara Seas. We hypothesize that those gradients are influenced by eastern (Norwegian Atlantic Current and West Spitsbergen Current) and western (East Greenland Current) oceanic currents and melting of the Greenland Ice Sheet. By tracking spatial Hg contamination in marine ecosystems and through the identification of areas at risk of Hg toxicity, this study provides essential knowledge for international decisions about where the regulation of pollutants should be prioritized.


Assuntos
Plumas , Mercúrio , Animais , Mercúrio/análise , Oceano Atlântico , Plumas/química , Regiões Árticas , Groenlândia , Monitoramento Ambiental/métodos , Aves , Cadeia Alimentar , Poluentes Químicos da Água/análise , Ecossistema
15.
Sci Rep ; 14(1): 12027, 2024 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797747

RESUMO

Increasing Arctic temperatures are facilitating the northward expansion of more southerly hosts, vectors, and pathogens, exposing naïve populations to pathogens not typical at northern latitudes. To understand such rapidly changing host-pathogen dynamics, we need sensitive and robust surveillance tools. Here, we use a novel multiplexed magnetic-capture and droplet digital PCR (ddPCR) tool to assess a sentinel Arctic species, the polar bear (Ursus maritimus; n = 68), for the presence of five zoonotic pathogens (Erysipelothrix rhusiopathiae, Francisella tularensis, Mycobacterium tuberculosis complex, Toxoplasma gondii and Trichinella spp.), and observe associations between pathogen presence and biotic and abiotic predictors. We made two novel detections: the first detection of a Mycobacterium tuberculosis complex member in Arctic wildlife and the first of E. rhusiopathiae in a polar bear. We found a prevalence of 37% for E. rhusiopathiae, 16% for F. tularensis, 29% for Mycobacterium tuberculosis complex, 18% for T. gondii, and 75% for Trichinella spp. We also identify associations with bear age (Trichinella spp.), harvest season (F. tularensis and MTBC), and human settlements (E. rhusiopathiae, F. tularensis, MTBC, and Trichinella spp.). We demonstrate that monitoring a sentinel species, the polar bear, could be a powerful tool in disease surveillance and highlight the need to better characterize pathogen distributions and diversity in the Arctic.


Assuntos
Ursidae , Zoonoses , Ursidae/microbiologia , Ursidae/parasitologia , Animais , Regiões Árticas , Zoonoses/parasitologia , Zoonoses/microbiologia , Zoonoses/epidemiologia , Canadá/epidemiologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Trichinella/isolamento & purificação , Trichinella/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Francisella tularensis/isolamento & purificação , Francisella tularensis/genética , Feminino , Masculino
16.
Environ Sci Technol ; 58(20): 8748-8759, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38709019

RESUMO

Sea spray aerosols (SSA) greatly affect the climate system by scattering solar radiation and acting as seeds for cloud droplet formation. The ecosystems in the Arctic Ocean are rapidly changing due to global warming, and the effects these changes have on the generation of SSA, and thereby clouds and fog formation in this region, are unknown. During the ship-based Arctic Century Expedition, we examined the dependency of forced SSA production on the biogeochemical characteristics of seawater using an on-board temperature-controlled aerosol generation chamber with a plunging jet system. Our results indicate that mainly seawater salinity and organic content influence the production and size distribution of SSA. However, we observed a 2-fold higher SSA production from waters with similar salinity collected north of 81°N compared to samples collected south of this latitude. This variability was not explained by phytoplankton and bacterial abundances or Chlorophyll-a concentration but by the presence of glucose in seawater. The synergic action of sea salt (essential component) and glucose or glucose-rich saccharides (enhancer) accounts for >80% of SSA predictability throughout the cruise. Our results suggest that besides wind speed and salinity, SSA production in Arctic waters is also affected by specific organics released by the microbiota.


Assuntos
Aerossóis , Glucose , Salinidade , Água do Mar , Regiões Árticas , Água do Mar/química , Glucose/metabolismo , Fitoplâncton
17.
Sci Total Environ ; 933: 173049, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735321

RESUMO

Arctic and subarctic ecosystems are experiencing rapid changes in vegetation composition and productivity due to global warming. Tundra wetlands are especially susceptible to these changes, which may trigger shifts in soil moisture dynamics. It is therefore essential to accurately map plant biomass and topsoil moisture. In this study, we mapped total, wood, and leaf above ground biomass and topsoil moisture in subarctic tundra wetlands located between Norway and Finland by linking models derived from Unoccupied Aerial Vehicles with multiple satellite data sources using the Extreme Gradient Boosting algorithm. The most accurate predictions for topsoil moisture (R2 = 0.73) used a set of red edge-based vegetation indices with a spatial resolution of 20 m per pixel. On the contrary, wood biomass showed the lowest accuracies across all tested models (R2 = 0.38). We found a trade-off between the spatial resolution and the performance of upscaling models, where smaller pixel sizes generally led to lower accuracies. However, we were able to compensate for reduced accuracy at smaller pixel sizes using Copernicus phenology metrics. A modelling uncertainty assessment revealed that the uncertainty of predictions increased with decreasing pixel sizes and increasing number of co-predictors. Our approach could improve efforts to map and monitor changes in vegetation at regional to pan-Arctic scales.


Assuntos
Biomassa , Monitoramento Ambiental , Solo , Monitoramento Ambiental/métodos , Solo/química , Finlândia , Noruega , Áreas Alagadas , Tundra , Regiões Árticas , Tecnologia de Sensoriamento Remoto
18.
Nat Microbiol ; 9(6): 1454-1466, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38806673

RESUMO

With rising global temperatures, permafrost carbon stores are vulnerable to microbial degradation. The enzyme latch theory states that polyphenols should accumulate in saturated peatlands due to diminished phenol oxidase activity, inhibiting resident microbes and promoting carbon stabilization. Pairing microbiome and geochemical measurements along a permafrost thaw-induced saturation gradient in Stordalen Mire, a model Arctic peatland, we confirmed a negative relationship between phenol oxidase expression and saturation but failed to support other trends predicted by the enzyme latch. To inventory alternative polyphenol removal strategies, we built CAMPER, a gene annotation tool leveraging polyphenol enzyme knowledge gleaned across microbial ecosystems. Applying CAMPER to genome-resolved metatranscriptomes, we identified genes for diverse polyphenol-active enzymes expressed by various microbial lineages under a range of redox conditions. This shifts the paradigm that polyphenols stabilize carbon in saturated soils and highlights the need to consider both oxic and anoxic polyphenol metabolisms to understand carbon cycling in changing ecosystems.


Assuntos
Ciclo do Carbono , Microbiota , Pergelissolo , Polifenóis , Microbiologia do Solo , Polifenóis/metabolismo , Pergelissolo/microbiologia , Bactérias/metabolismo , Bactérias/genética , Bactérias/enzimologia , Bactérias/classificação , Carbono/metabolismo , Oxirredução , Regiões Árticas , Monofenol Mono-Oxigenase/metabolismo , Monofenol Mono-Oxigenase/genética , Solo/química , Ecossistema
19.
Mar Pollut Bull ; 203: 116473, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38820879

RESUMO

EcoQS assessment of the marine intertidal zone based on its fauna is challenging because the assemblages have a low diversity and consist of stress tolerant species. The new approach we propose is to pool foraminiferal diversity (effective number of species exp(H'bc)) across the whole intertidal zone including the salt marsh and tidal flat. In seven fjordheads studied in northern Fennoscandia, polycyclic aromatic hydrocarbon (PAH) concentrations indicated low levels of pollution (EcoQSPAH Excellent to Moderate). Jadammina or Balticammina dominated the salt marsh, Elphidium albiumbilicatum, Elphidium williamsoni, Elphidium clavatum, and Buccella frigida occurred in the tidal flat. Ovammina opaca thrived in both belts. While foraminiferal test abnormalities are often proposed to measure pollution impacts, we did not detect any correlation with PAHs. EcoQS based on foraminiferal diversity (EcoQSforam Excellent to Good) matched EcoQS based on PAHs suggesting that pooled foraminiferal diversity reliably measures intertidal EcoQS.


Assuntos
Biodiversidade , Monitoramento Ambiental , Foraminíferos , Hidrocarbonetos Policíclicos Aromáticos , Foraminíferos/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental/métodos , Regiões Árticas , Poluentes Químicos da Água/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-38722773

RESUMO

A yellow pigmented, Gram-stain-positive, motile, facultatively anaerobic and irregular rod-shaped bacteria (strain M0-14T) was isolated from a till sample collected from the foreland of a high Arctic glacier near the settlement of Ny-Ålesund in the Svalbard Archipelago, Norway. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that M0-14T formed a lineage within the family Cellulomonadaceae, suborder Micrococcineae. M0-14T represented a novel member of the genus Pengzhenrongella and had highest 16S rRNA gene sequence similarity to Pengzhenrongella sicca LRZ-2T (97.3 %). Growth occurred at 4-25 °C (optimum 4-18 °C), at pH 6.0-9.0 (optimum pH 7.0), and in the presence of 0-5 % (w/v) NaCl. The predominant menaquinone was MK-9(H4) and the major fatty acids were anteiso-C15 : 0, C16 : 0 and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). The major polar lipids were phosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylinositol, one undefined phospholipid and five undefined phosphoglycolipids. The cell-wall diamino acid was l-ornithine whereas rhamnose and mannose were the cell-wall sugars. Polyphosphate particles were found inside the cells of M0-14T. Polyphosphate kinase and polyphosphate-dependent glucokinase genes were detected during genomic sequencing of M0-14. In addition, the complete pstSCAB gene cluster and phnCDE synthesis genes, which are important for the uptake and transport of phosphorus in cells, were annotated in the genomic data. According to the genomic data, M0-14T has a metabolic pathway related to phosphorus accumulation. The DNA G+C content of the genomic DNA was 70.8 %. On the basis of its phylogenetic relationship, phenotypic properties and chemotaxonomic distinctiveness, strain M0-14T represents a novel species of the genus Pengzhenrongella, for which the name Pengzhenrongella phosphoraccumulans sp. nov. is proposed. The type strain is M0-14T (= CCTCC AB 2012967T = NRRL B-59105T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Camada de Gelo , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Vitamina K 2 , RNA Ribossômico 16S/genética , Regiões Árticas , Ácidos Graxos/química , Vitamina K 2/análogos & derivados , DNA Bacteriano/genética , Camada de Gelo/microbiologia , Fosfolipídeos , Svalbard
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