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1.
Article in English | MEDLINE | ID: mdl-38722773

ABSTRACT

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).


Subject(s)
Bacterial Typing Techniques , Base Composition , DNA, Bacterial , Fatty Acids , Ice Cover , Phylogeny , RNA, Ribosomal, 16S , Sequence Analysis, DNA , Vitamin K 2 , RNA, Ribosomal, 16S/genetics , Arctic Regions , Fatty Acids/chemistry , Vitamin K 2/analogs & derivatives , DNA, Bacterial/genetics , Ice Cover/microbiology , Phospholipids , Svalbard
2.
Glob Chang Biol ; 30(5): e17273, 2024 May.
Article in English | MEDLINE | ID: mdl-38727723

ABSTRACT

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.


Subject(s)
Biodiversity , Climate Change , Fishes , Temperature , Animals , Fishes/physiology , Norway , Arctic Regions
3.
Environ Microbiol ; 26(5): e16640, 2024 May.
Article in English | MEDLINE | ID: mdl-38775217

ABSTRACT

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.


Subject(s)
Genome, Bacterial , Phylogeny , Soil Microbiology , Tundra , Acidobacteria/genetics , Acidobacteria/classification , Acidobacteria/isolation & purification , RNA, Ribosomal, 16S/genetics , Arctic Regions
4.
Int J Circumpolar Health ; 83(1): 2359161, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38785137

ABSTRACT

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.


Subject(s)
Food Security , Food Supply , Humans , Alaska , Female , Male , Adult , Diet , Middle Aged , Surveys and Questionnaires , Alaska Natives , Arctic Regions
5.
Parasite ; 31: 26, 2024.
Article in English | MEDLINE | ID: mdl-38775717

ABSTRACT

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.


Subject(s)
Phylogeny , Trematoda , Trematode Infections , Animals , Trematoda/classification , Trematoda/anatomy & histology , Trematoda/isolation & purification , Trematoda/genetics , Arctic Regions , Trematode Infections/veterinary , Trematode Infections/parasitology , Sweden , Fish Diseases/parasitology , RNA, Ribosomal, 28S/genetics , Gadiformes/parasitology , Svalbard , DNA, Helminth
6.
BMC Health Serv Res ; 24(1): 656, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778349

ABSTRACT

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.


Subject(s)
Focus Groups , Health Services Research , Leadership , Rural Health Services , Humans , Rural Health Services/organization & administration , Female , Arctic Regions , Male , Staff Development , Program Development , Adult , Middle Aged , Qualitative Research
7.
Article in English | MEDLINE | ID: mdl-38780584

ABSTRACT

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.


Subject(s)
DNA, Fungal , Phylogeny , Seawater , Sequence Analysis, DNA , Arctic Regions , DNA, Fungal/genetics , Seawater/microbiology , Mycological Typing Techniques , Svalbard , RNA, Ribosomal, 28S/genetics , Basidiomycota/genetics , Basidiomycota/classification , Basidiomycota/isolation & purification , Fresh Water/microbiology , Ecosystem , Cold Temperature , Saccharomycetales/classification , Saccharomycetales/genetics , Saccharomycetales/isolation & purification
8.
Sci Adv ; 10(20): eadl5904, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758795

ABSTRACT

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.


Subject(s)
Climate Change , Ecosystem , Phytoplankton , Phytoplankton/physiology , Arctic Regions , Hot Temperature , Global Warming
9.
Environ Sci Technol ; 58(19): 8490-8500, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38696308

ABSTRACT

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.


Subject(s)
Carbon , Soil Pollutants , Soil , Soil/chemistry , Persistent Organic Pollutants , Environmental Monitoring , Arctic Regions , Ecosystem
10.
Int J Circumpolar Health ; 83(1): 2349330, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38726478

ABSTRACT

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.


Subject(s)
Health Promotion , Qualitative Research , Stress, Psychological , Humans , Sweden , Male , Female , Health Promotion/organization & administration , Adult , Middle Aged , Interviews as Topic , Nature , Arctic Regions , Health Personnel/psychology
11.
Proc Natl Acad Sci U S A ; 121(21): e2315513121, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38739784

ABSTRACT

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.


Subject(s)
Feathers , Mercury , Animals , Mercury/analysis , Atlantic Ocean , Feathers/chemistry , Arctic Regions , Greenland , Environmental Monitoring/methods , Birds , Food Chain , Water Pollutants, Chemical/analysis , Ecosystem
12.
Sci Rep ; 14(1): 12027, 2024 May 26.
Article in English | MEDLINE | ID: mdl-38797747

ABSTRACT

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.


Subject(s)
Ursidae , Zoonoses , Ursidae/microbiology , Ursidae/parasitology , Animals , Arctic Regions , Zoonoses/parasitology , Zoonoses/microbiology , Zoonoses/epidemiology , Canada/epidemiology , Toxoplasma/genetics , Toxoplasma/isolation & purification , Trichinella/isolation & purification , Trichinella/genetics , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , Francisella tularensis/isolation & purification , Francisella tularensis/genetics , Female , Male
13.
Sci Total Environ ; 933: 173049, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38735321

ABSTRACT

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.


Subject(s)
Biomass , Environmental Monitoring , Soil , Environmental Monitoring/methods , Soil/chemistry , Finland , Norway , Wetlands , Tundra , Arctic Regions , Remote Sensing Technology
14.
Glob Chang Biol ; 30(5): e17300, 2024 May.
Article in English | MEDLINE | ID: mdl-38738563

ABSTRACT

Rhodoliths built by crustose coralline algae (CCA) are ecosystem engineers of global importance. In the Arctic photic zone, their three-dimensional growth emulates the habitat complexity of coral reefs but with a far slower growth rate, growing at micrometers per year rather than millimeters. While climate change is known to exert various impacts on the CCA's calcite skeleton, including geochemical and structural alterations, field observations of net growth over decade-long timescales are lacking. Here, we use a temporally explicit model to show that rising ocean temperatures over nearly 100 years were associated with reduced rhodolith growth at different depths in the Arctic. Over the past 90 years, the median growth rate was 85 µm year-1 but each °C increase in summer seawater temperature decreased growth by a mean of 8.9 µm (95% confidence intervals = 1.32-16.60 µm °C-1, p < .05). The decrease was expressed for rhodolith occurrences in 11 and 27 m water depth but not at 46 m, also having the shortest time series (1991-2015). Although increasing temperatures can spur plant growth, we suggest anthropogenic climate change has either exceeded the population thermal optimum for these CCA, or synergistic effects of warming, ocean acidification, and/or increasing turbidity impair rhodolith growth. Rhodoliths built by calcitic CCA are important habitat providers worldwide, so decreased growth would lead to yet another facet of anthropogenic habitat loss.


Subject(s)
Climate Change , Rhodophyta , Temperature , Arctic Regions , Rhodophyta/growth & development , Rhodophyta/physiology , Seawater/chemistry
15.
Environ Sci Technol ; 58(20): 8748-8759, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38709019

ABSTRACT

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.


Subject(s)
Aerosols , Glucose , Salinity , Seawater , Arctic Regions , Seawater/chemistry , Glucose/metabolism , Phytoplankton
16.
Glob Chang Biol ; 30(5): e17335, 2024 May.
Article in English | MEDLINE | ID: mdl-38771086

ABSTRACT

Global climate change has altered the timing of seasonal events (i.e., phenology) for a diverse range of biota. Within and among species, however, the degree to which alterations in phenology match climate variability differ substantially. To better understand factors driving these differences, we evaluated variation in timing of nesting of eight Arctic-breeding shorebird species at 18 sites over a 23-year period. We used the Normalized Difference Vegetation Index as a proxy to determine the start of spring (SOS) growing season and quantified relationships between SOS and nest initiation dates as a measure of phenological responsiveness. Among species, we tested four life history traits (migration distance, seasonal timing of breeding, female body mass, expected female reproductive effort) as species-level predictors of responsiveness. For one species (Semipalmated Sandpiper), we also evaluated whether responsiveness varied across sites. Although no species in our study completely tracked annual variation in SOS, phenological responses were strongest for Western Sandpipers, Pectoral Sandpipers, and Red Phalaropes. Migration distance was the strongest additional predictor of responsiveness, with longer-distance migrant species generally tracking variation in SOS more closely than species that migrate shorter distances. Semipalmated Sandpipers are a widely distributed species, but adjustments in timing of nesting relative to variability in SOS did not vary across sites, suggesting that different breeding populations of this species were equally responsive to climate cues despite differing migration strategies. Our results unexpectedly show that long-distance migrants are more sensitive to local environmental conditions, which may help them to adapt to ongoing changes in climate.


Subject(s)
Animal Migration , Climate Change , Nesting Behavior , Seasons , Animals , Arctic Regions , Animal Migration/physiology , Female , Charadriiformes/physiology , Reproduction
19.
Sci Rep ; 14(1): 9925, 2024 04 30.
Article in English | MEDLINE | ID: mdl-38688926

ABSTRACT

Drowsiness while driving negatively impacts road safety, especially in truck drivers. The present study investigated the feasibility and alerting effects of a daylight-supplementing in-truck lighting system (DS) providing short-wavelength enriched light before, during, and after driving. In a within-participants design, eight truck drivers drove a fully-loaded truck under wintry Scandinavian conditions (low daylight levels) with a DS or placebo system for five days. Subjective and objective measures of alertness were recorded several times daily, and evening melatonin levels were recorded three times per study condition. DS significantly increased daytime light exposure without causing negative side effects while driving. In addition, no negative carry-over effects were observed on evening melatonin and sleepiness levels or on nighttime sleep quality. Moreover, objective alertness (i.e., psychomotor vigilance) before and after driving was significantly improved by bright light exposure. This effect was accompanied by improved subjective alertness in the morning. This field study demonstrated that DS was able to increase daytime light exposure in low-daylight conditions and to improve alertness in truck drivers before and after driving (e.g., during driving rest periods). Further studies are warranted to investigate the effects of daylight-supplementing in-cabin lighting on driving performance and road safety measures.


Subject(s)
Automobile Driving , Lighting , Melatonin , Motor Vehicles , Humans , Male , Adult , Melatonin/metabolism , Seasons , Arctic Regions , Wakefulness/physiology , Wakefulness/radiation effects , Female , Middle Aged , Psychomotor Performance/radiation effects , Light , Circadian Rhythm/physiology , Truck Drivers
20.
Int J Circumpolar Health ; 83(1): 2341990, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38669637

ABSTRACT

The Circumpolar region, comprising the Arctic territories encircling the North Pole, is home to diverse Indigenous cultures facing unique socio-economic challenges. Indigenous communities such as the Inuit, Sámi, Athabaskan, Gwitchin, and Russian Arctic groups exhibit rich traditions and adaptive practices tied to their environments. Environmental diversity, from icy tundra to boreal forests, influences livelihoods and biodiversity, while significant socio-economic disparities persist, impacting access to healthcare, education, and economic opportunities. Against this backdrop, the global COVID-19 pandemic accentuated the intersection of environment, culture, and health in remote Arctic regions, presenting distinct challenges and opportunities. Initiated by a collaborative research project led by Fulbright Arctic Initiative Alumni, this special issue of the International Journal of Circumpolar Health explores the impacts of COVID-19 on Arctic Indigenous and rural communities. Building on previous work and recommendations, the issue features community case studies, highlighting community experiences and collaborative approaches to understand and address the pandemic's effects. The authors highlight both positive and negative societal outcomes, presenting community-driven models and evidence-based practices to inform pan-Arctic collaboration and decision-making in public health emergencies. Through sharing these insights, the special issue aims to privilege local and Indigenous knowledge systems, elevates community responses to complex and multifaceted challenges, and contributes to the evidence base on global pandemic response.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19/epidemiology , COVID-19/ethnology , Arctic Regions/epidemiology , Pandemics
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