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1.
Int J Circumpolar Health ; 83(1): 2349330, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38726478

RESUMEN

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.


Asunto(s)
Promoción de la Salud , Investigación Cualitativa , Estrés Psicológico , Humanos , Suecia , Masculino , Femenino , Promoción de la Salud/organización & administración , Adulto , Persona de Mediana Edad , Entrevistas como Asunto , Naturaleza , Regiones Árticas , Personal de Salud/psicología
2.
Artículo en Inglés | MEDLINE | ID: mdl-38722773

RESUMEN

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).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Cubierta de Hielo , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Vitamina K 2 , ARN Ribosómico 16S/genética , Regiones Árticas , Ácidos Grasos/química , Vitamina K 2/análogos & derivados , ADN Bacteriano/genética , Cubierta de Hielo/microbiología , Fosfolípidos , Svalbard
3.
Glob Chang Biol ; 30(5): e17273, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38727723

RESUMEN

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.


Asunto(s)
Biodiversidad , Cambio Climático , Peces , Temperatura , Animales , Peces/fisiología , Noruega , Regiones Árticas
4.
Proc Natl Acad Sci U S A ; 121(21): e2315513121, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38739784

RESUMEN

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.


Asunto(s)
Plumas , Mercurio , Animales , Mercurio/análisis , Océano Atlántico , Plumas/química , Regiones Árticas , Groenlandia , Monitoreo del Ambiente/métodos , Aves , Cadena Alimentaria , Contaminantes Químicos del Agua/análisis , Ecosistema
5.
Glob Chang Biol ; 30(5): e17300, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38738563

RESUMEN

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.


Asunto(s)
Cambio Climático , Rhodophyta , Temperatura , Regiones Árticas , Rhodophyta/crecimiento & desarrollo , Rhodophyta/fisiología , Agua de Mar/química
6.
Environ Sci Technol ; 58(19): 8490-8500, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696308

RESUMEN

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.


Asunto(s)
Carbono , Contaminantes del Suelo , Suelo , Suelo/química , Contaminantes Orgánicos Persistentes , Monitoreo del Ambiente , Regiones Árticas , Ecosistema
7.
Proc Natl Acad Sci U S A ; 121(19): e2311116121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38683977

RESUMEN

Conventionally, women are perceived to feel colder than men, but controlled comparisons are sparse. We measured the response of healthy, lean, young women and men to a range of ambient temperatures typical of the daily environment (17 to 31 °C). The Scholander model of thermoregulation defines the lower critical temperature as threshold of the thermoneutral zone, below which additional heat production is required to defend core body temperature. This parameter can be used to characterize the thermoregulatory phenotypes of endotherms on a spectrum from "arctic" to "tropical." We found that women had a cooler lower critical temperature (mean ± SD: 21.9 ± 1.3 °C vs. 22.9 ± 1.2 °C, P = 0.047), resembling an "arctic" shift compared to men. The more arctic profile of women was predominantly driven by higher insulation associated with more body fat compared to men, countering the lower basal metabolic rate associated with their smaller body size, which typically favors a "tropical" shift. We did not detect sex-based differences in secondary measures of thermoregulation including brown adipose tissue glucose uptake, muscle electrical activity, skin temperatures, cold-induced thermogenesis, or self-reported thermal comfort. In conclusion, the principal contributors to individual differences in human thermoregulation are physical attributes, including body size and composition, which may be partly mediated by sex.


Asunto(s)
Regulación de la Temperatura Corporal , Humanos , Femenino , Masculino , Regulación de la Temperatura Corporal/fisiología , Adulto , Regiones Árticas , Adulto Joven , Tejido Adiposo Pardo/fisiología , Tejido Adiposo Pardo/metabolismo , Caracteres Sexuales , Factores Sexuales , Temperatura Corporal/fisiología , Termogénesis/fisiología , Metabolismo Basal/fisiología
8.
Mar Pollut Bull ; 202: 116365, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608430

RESUMEN

Plastic pollution threatens many organisms around the world. In particular, the northern fulmar, Fulmarus glacialis, is known to ingest high quantities of plastics. Since data are sparse in the Eurasian Arctic, we investigated plastic burdens in the stomachs of fulmar fledglings from Kongsfjorden, Svalbard. Fifteen birds were collected and only particles larger than 1 mm were extracted, characterised and analysed with Fourier Transform InfraRed spectroscopy. All birds ingested plastic. In total, 683 plastic particles were found, with an average of 46 ± 40 SD items per bird. The most common shape, colour and polymer were hard fragment, white, and polyethylene, respectively. Microplastics (< 5 mm) were slightly more represented than mesoplastics (> 5 mm). This study confirms high numbers of ingested plastics in fulmar fledglings from Svalbard and suggests that fulmar fledglings may be suitable for temporal monitoring of plastic pollution, avoiding potential biases caused by age composition or breeding state.


Asunto(s)
Aves , Monitoreo del Ambiente , Plásticos , Animales , Plásticos/análisis , Svalbard , Contaminantes Químicos del Agua/análisis , Microplásticos/análisis , Regiones Árticas
9.
Mar Pollut Bull ; 202: 116338, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38640763

RESUMEN

Comprehensive methodologies for monitoring microplastics (MPs) in the ocean are critical for accurately assessing abundances across a broad size spectrum, and to document distributions, sources, sinks, temporal trends, and exposure risks for organisms. Discrete 0.5-L water samples from the northeastern-coast of Venezuela (NECV), Pacific-Arctic Ocean (PAO), and Gulf Stream Current (GSC) were analyzed by Raman microspectroscopy to detect MPs not captured by net-tow surveys. Equivalent spherical diameters (ESD) of most MPs were <5 µm, accounting for 68, 83, 86 % of total inventories in NECV, GSC, PAO samples. We did not observe a single MP particle >53 µm ESD. Abundances of MPs in the 0.5-200 µm size fraction were 5-6 orders of magnitude higher than previous surveys that were almost exclusively based on net tow collections of MPs > 300 µm ESD. Abundances of MPs in NECV samples were ~10-fold higher than those from PAO and GSC. The most abundant polymers were polypropylene (PP), polystyrene (PS) and polyethylene terephthalate (PET), consistent with composition of plastic waste generated globally.


Asunto(s)
Monitoreo del Ambiente , Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Contaminantes Químicos del Agua/análisis , Regiones Árticas , Región del Caribe , Plásticos/análisis , Océanos y Mares
10.
Int J Circumpolar Health ; 83(1): 2339561, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38615335

RESUMEN

In the last decade, policy strategies were adopted in response to population ageing in the Nordic countries. Governmental actions have to be evaluated in terms of their efficacy. The objective of this article is to identify and review the policies related to age-inclusive outdoor spaces in the Arctic regions of Nordic countries. Our analysis focuses on central government white papers that address the older adults in Finland, Norway, Sweden, and Iceland. A review of such policy documents provides insights into the predominant understandings of older adults and healthy ageing. Moreover, such analysis may identify "blind spots" in the national policies, especially regarding the sparsely researched northernmost and rural Arctic territories. Our results demonstrate how the older populations in the Nordic Arctic and their access to outdoor spaces are addressed in the policy documents. We found that with few exceptions, the older people of the rural Arctic is strikingly absent in the Nordic national governmental papers. Moreover, access to outdoor spaces is mentioned in general terms, and specific challenges of the rural Arctic context, such as the harsh climate, long winters and geographical distances are not addressed. The noticed omissions might be the result of "urban-rural", "south-north", "indoor-outdoor", and "generalisation" biases.


Asunto(s)
Políticas , Humanos , Anciano , Regiones Árticas , Países Escandinavos y Nórdicos , Finlandia , Islandia
11.
FEMS Microbiol Ecol ; 100(6)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38653723

RESUMEN

Cyanobacterial mats are commonly reported as hotspots of microbial diversity across polar environments. These thick, multilayered microbial communities provide a refuge from extreme environmental conditions, with many species able to grow and coexist despite the low allochthonous nutrient inputs. The visibly dominant phototrophic biomass is dependent on internal nutrient recycling by heterotrophic organisms within the mats; however, the specific contribution of heterotrophic protists remains little explored. In this study, mat community diversity was examined along a latitudinal gradient (55-83°N), spanning subarctic taiga, tundra, polar desert, and the High Arctic ice shelves. The prokaryotic and eukaryotic communities were targeted, respectively, by V4 16S ribosomal RNA (rRNA) and V9 18S rRNA gene amplicon high-throughput sequencing. Prokaryotic and eukaryotic richness decreased, in tandem with decreasing temperatures and shorter seasons of light availability, from the subarctic to the High Arctic. Taxonomy-based annotation of the protist community revealed diverse phototrophic, mixotrophic, and heterotrophic genera in all mat communities, with fewer parasitic taxa in High Arctic communities. Co-occurrence network analysis identified greater heterogeneity in eukaryotic than prokaryotic community structure among cyanobacterial mats across the Canadian Arctic. Our findings highlight the sensitivity of microbial eukaryotes to environmental gradients across northern high latitudes.


Asunto(s)
Biodiversidad , Cianobacterias , ARN Ribosómico 16S , Regiones Árticas , Cianobacterias/genética , Cianobacterias/clasificación , Canadá , ARN Ribosómico 16S/genética , Microbiota , ARN Ribosómico 18S/genética , Tundra
12.
Environ Microbiol ; 26(4): e16617, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38558266

RESUMEN

Sunlight penetrates the ice surfaces of glaciers and ice sheets, forming a water-bearing porous ice matrix known as the weathering crust. This crust is home to a significant microbial community. Despite the potential implications of microbial processes in the weathering crust for glacial melting, biogeochemical cycles, and downstream ecosystems, there have been few explorations of its microbial communities. In our study, we used 16S rRNA gene sequencing and shotgun metagenomics of a Svalbard glacier surface catchment to characterise the microbial communities within the weathering crust, their origins and destinies, and the functional potential of the weathering crust metagenome. Our findings reveal that the bacterial community in the weathering crust is distinct from those in upstream and downstream habitats. However, it comprises two separate micro-habitats, each with different taxa and functional categories. The interstitial porewater is dominated by Polaromonas, influenced by the transfer of snowmelt, and exported via meltwater channels. In contrast, the ice matrix is dominated by Hymenobacter, and its metagenome exhibits a diverse range of functional adaptations. Given that the global weathering crust area and the subsequent release of microbes from it are strongly responsive to climate projections for the rest of the century, our results underscore the pressing need to integrate the microbiome of the weathering crust with other communities and processes in glacial ecosystems.


Asunto(s)
Cubierta de Hielo , Microbiota , Cubierta de Hielo/microbiología , ARN Ribosómico 16S/genética , Microbiota/genética , Bacterias/genética , Regiones Árticas
13.
Int J Circumpolar Health ; 83(1): 2341990, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38669637

RESUMEN

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.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/etnología , Regiones Árticas/epidemiología , Pandemias
14.
Sci Rep ; 14(1): 8192, 2024 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589522

RESUMEN

In Fram Strait, we combined underway-sampling using the remote-controlled Automated Filtration System for Marine Microbes (AUTOFIM) with CTD-sampling for eDNA analyses, and with high-resolution optical measurements in an unprecedented approach to determine variability in plankton composition in response to physical forcing in a sub-mesoscale filament. We determined plankton composition and biomass near the surface with a horizontal resolution of ~ 2 km, and addressed vertical variability at five selected sites. Inside and near the filament, plankton composition was tightly linked to the hydrological dynamics related to the presence of sea ice. The comprehensive data set indicates that sea-ice melt related stratification near the surface inside the sub-mesoscale filament resulted in increased sequence abundances of sea ice-associated diatoms and zooplankton near the surface. In analogy to the physical data set, the underway eDNA data, complemented with highly sampled phytoplankton pigment data suggest a corridor of 7 km along the filament with enhanced photosynthetic biomass and sequence abundances of sea-ice associated plankton. Thus, based on our data we extrapolated an area of 350 km2 in Fram Strait with enhanced plankton abundances, possibly leading to enhanced POC export in an area that is around a magnitude larger than the visible streak of sea-ice.


Asunto(s)
Plancton , Zooplancton , Animales , Biomasa , Plancton/genética , Zooplancton/genética , Fotosíntesis , Fitoplancton/genética , Regiones Árticas , Ecosistema , Cubierta de Hielo
15.
Int J Circumpolar Health ; 83(1): 2336284, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38573784

RESUMEN

This paper outlines the methodological approaches to a multi-site Circumpolar case study exploring the impacts of COVID-19 on Indigenous and remote communities in 7 of 8 Arctic countries. Researchers involved with the project implemented a three-phase multi-site case study to assess the positive and negative societal outcomes associated with the COVID-19 pandemic in Arctic communities from 2020 to 2023. The goal of the multi-site case study was to identify community-driven models and evidence-based promising practices and recommendations that can help inform cohesive and coordinated public health responses and protocols related to future public health emergencies in the Arctic. Research sites included a minimum of 1 one community each from Canada (Nunavut,) United States of America (Alaska), Greenland, Iceland, Norway, Sweden, Finland. The approaches used for our multi-site case study provide a comprehensive, evidence-based account of the complex health challenges facing Arctic communities, offering insights into the effectiveness of interventions, while also privileging Indigenous local knowledge and voices. The mixed method multi-site case study approach enriched the understanding of unique regional health disparities and strengths during the pandemic. These methodological approaches serve as a valuable resource for policymakers, researchers, and healthcare professionals, informing future strategies and interventions.


Asunto(s)
COVID-19 , Pandemias , Humanos , Regiones Árticas , Alaska/epidemiología , Canadá , Groenlandia
17.
Nature ; 629(8010): 105-113, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38632407

RESUMEN

Arctic and alpine tundra ecosystems are large reservoirs of organic carbon1,2. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5-7. This hampers the accuracy of global land carbon-climate feedback projections7,8. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9-2.0 °C] in air and 0.4 °C [CI 0.2-0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22-38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.


Asunto(s)
Respiración de la Célula , Ecosistema , Calentamiento Global , Tundra , Regiones Árticas , Carbono/metabolismo , Carbono/análisis , Ciclo del Carbono , Conjuntos de Datos como Asunto , Concentración de Iones de Hidrógeno , Nitrógeno/metabolismo , Nitrógeno/análisis , Plantas/metabolismo , Estaciones del Año , Suelo/química , Microbiología del Suelo , Temperatura , Factores de Tiempo
18.
FEMS Microbiol Ecol ; 100(5)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38621717

RESUMEN

The hydrographic variability in the fjords of Svalbard significantly influences water mass properties, causing distinct patterns of microbial diversity and community composition between surface and subsurface layers. However, surveys on the phytoplankton-associated bacterial communities, pivotal to ecosystem functioning in Arctic fjords, are limited. This study investigated the interactions between phytoplankton and heterotrophic bacterial communities in Svalbard fjord waters through comprehensive eDNA metabarcoding with 16S and 18S rRNA genes. The 16S rRNA sequencing results revealed a homogenous community composition including a few dominant heterotrophic bacteria across fjord waters, whereas 18S rRNA results suggested a spatially diverse eukaryotic plankton distribution. The relative abundances of heterotrophic bacteria showed a depth-wise distribution. By contrast, the dominant phytoplankton populations exhibited variable distributions in surface waters. In the network model, the linkage of phytoplankton (Prasinophytae and Dinophyceae) to heterotrophic bacteria, particularly Actinobacteria, suggested the direct or indirect influence of bacterial contributions on the fate of phytoplankton-derived organic matter. Our prediction of the metabolic pathways for bacterial activity related to phytoplankton-derived organic matter suggested competitive advantages and symbiotic relationships between phytoplankton and heterotrophic bacteria. Our findings provide valuable insights into the response of phytoplankton-bacterial interactions to environmental changes in Arctic fjords.


Asunto(s)
Bacterias , Procesos Heterotróficos , Fitoplancton , ARN Ribosómico 16S , ARN Ribosómico 18S , Estaciones del Año , Fitoplancton/genética , Fitoplancton/metabolismo , Regiones Árticas , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/aislamiento & purificación , ARN Ribosómico 16S/genética , ARN Ribosómico 18S/genética , Código de Barras del ADN Taxonómico , Estuarios , Svalbard , Cubierta de Hielo/microbiología , Ecosistema , ADN Bacteriano/genética , Biodiversidad , Microbiota/genética
19.
Sci Total Environ ; 929: 172431, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38663616

RESUMEN

Recent advancements in spatial modelling leverage remote sensing data and statistical species-environment relationships to forecast the distribution of a specific species. Our study focuses on Disko Bay in West Greenland, recognized as a significant marine biodiversity hotspot in the region. We conducted comprehensive analyses using multiple datasets spanning from 2010 to 2019, incorporating shrimp and fish surveys, commercial shrimp fishery catches, high-resolution (25 × 25 m) multibeam bathymetry and backscatter data along with a medium-resolution (200 × 200 m) bathymetric model, measured and modelled oceanographic data, and satellite chlorophyll data. Through multivariate regression analysis, we tested the significance of various physical factors (seafloor depth, sediment class, bottom water temperature, bottom water salinity, bottom current velocity, space, and time), biological factors (chlorophyll a, Greenland halibut (Reinhardtius hippoglossoides)), and anthropogenic impact (shrimp fishery; standardized catch per unit effort) on the density of northern shrimp in the area. Our results indicate a significant association between northern shrimp density, seafloor depth, and sediment class, explaining 36 % of the variation in shrimp density. Subsequently, we developed a high-resolution (optimized) spatial linear mixed-effect model to map the distribution of northern shrimp across Disko Bay, representing the first model of its kind developed for an Arctic area. The optimal habitat for northern shrimp is characterized by medium-deep waters (approximately 150-350 m), turbulent conditions, and mixed sediments, predominantly located in the northern and southern regions of Disko Bay. Notably, the northern region hosts a relatively diverse benthic community, with northern shrimp and sponges as the primary contributors of epibenthic biomass. This novel high-resolution model significantly enhances our understanding of the physical drivers and detailed spatial patterns influencing the distribution of northern shrimp in the Arctic.


Asunto(s)
Bahías , Ecosistema , Pandalidae , Animales , Groenlandia , Monitoreo del Ambiente , Biodiversidad , Regiones Árticas , Explotaciones Pesqueras
20.
Glob Chang Biol ; 30(5): e17293, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38687495

RESUMEN

Polar regions are relatively isolated from human activity and thus could offer insight into anthropogenic and ecological drivers of the spread of antibiotic resistance. Plasmids are of particular interest in this context given the central role that they are thought to play in the dissemination of antibiotic resistance genes (ARGs). However, plasmidomes are challenging to profile in environmental samples. The objective of this study was to compare various aspects of the plasmidome associated with glacial ice and adjacent aquatic environments across the high Arctic archipelago of Svalbard, representing a gradient of anthropogenic inputs and specific treated and untreated wastewater outflows to the sea. We accessed plasmidomes by applying enrichment cultures, plasmid isolation and shotgun Illumina sequencing of environmental samples. We examined the abundance and diversity of ARGs and other stress-response genes that might be co/cross-selected or co-transported in these environments, including biocide resistance genes (BRGs), metal resistance genes (MRGs), virulence genes (VGs) and integrons. We found striking differences between glacial ice and aquatic environments in terms of the ARGs carried by plasmids. We found a strong correlation between MRGs and ARGs in plasmids in the wastewaters and fjords. Alternatively, in glacial ice, VGs and BRGs genes were dominant, suggesting that glacial ice may be a repository of pathogenic strains. Moreover, ARGs were not found within the cassettes of integrons carried by the plasmids, which is suggestive of unique adaptive features of the microbial communities to their extreme environment. This study provides insight into the role of plasmids in facilitating bacterial adaptation to Arctic ecosystems as well as in shaping corresponding resistomes. Increasing human activity, warming of Arctic regions and associated increases in the meltwater run-off from glaciers could contribute to the release and spread of plasmid-related genes from Svalbard to the broader pool of ARGs in the Arctic Ocean.


Asunto(s)
Plásmidos , Plásmidos/genética , Regiones Árticas , Farmacorresistencia Bacteriana/genética , Svalbard , Farmacorresistencia Microbiana/genética , Virulencia/genética , Aguas Residuales/microbiología , Cubierta de Hielo/microbiología , Genes Bacterianos
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