Artikler, rapporter og annet (arktisk og marin biologi): Recent submissions
Now showing items 121-140 of 1607
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Connecting the multiple dimensions of global soil fungal diversity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-29)How the multiple facets of soil fungal diversity vary worldwide remains virtually unknown, hindering the management of this essential species-rich group. By sequencing high-resolution DNA markers in over 4000 topsoil samples from natural and human-altered ecosystems across all continents, we illustrate the distributions and drivers of different levels of taxonomic and phylogenetic diversity of fungi ... -
Trophic relationships in the Early Miocene Upper Marine Molasse of Baden-Württemberg, Southwest Germany, with special emphasis on the elasmobranch fauna
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11)The Early Miocene Upper Marine Molasse (OMM) in south-western Germany contains a diverse fossil ecosystem in which elasmobranch teeth are especially abundant. However, the scarcity of outcrops and sometimes poor preservation of fossils resulted in scant recent literature about the OMM. Here, we focus on the elasmobranch fauna to determine the trophic relationships within the OMM, using fossil ... -
Snowmelt progression drives habitat selection and vegetation disturbance by an Arctic avian herbivore
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-17)Arctic tundra vegetation is affected by rapid climatic change and fluctuating herbivore population sizes. Broad-billed geese, after their arrival in spring, feed intensively on belowground rhizomes, thereby disturbing soil, mosses, and vascular plant vegetation. Understanding of how springtime snowmelt patterns drive goose behavior is thus key to better predict the state of Arctic tundra ecosystems. ... -
Gut microbiome biogeography in reindeer supersedes millennia of ecological and evolutionary separation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-29)Ruminants are dependent on their gut microbiomes for nutrient extraction from plant diets. However, knowledge about the composition, diversity, function, and spatial structure of gut microbiomes, especially in wild ruminants, is limited, largely because analysis has been restricted to faeces or the rumen. In two geographically separated reindeer subspecies, 16S rRNA gene amplicon sequencing revealed ... -
Global economic drivers in the development of different industrial hubs in the European Arctic
(Research report; Forskningsrapport, 2022-03)This project report discusses global drivers affecting the development of key industries in the European Arctic (EA). Aquaculture is important for littoral states in the North, forestry and mining for northern Scandinavia, and tourism throughout the northern regions in the EA, and all are affected by globalization. Globalization is not a homogeneous, uniform phenomenon, but consists of various global ... -
From Winter to Late Summer in the Northwestern Barents Sea Shelf: Impacts of Seasonal Progression of Sea Ice and Upper Ocean on Nutrient and Phytoplankton Dynamics
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-11)Strong seasonality is a key feature of high-latitude systems like the Barents Sea. While the interannual variability and long-term changes of the Barents Sea are well-documented, the seasonal progression of the physical and biological systems is less known, mainly due to poor accessibility of the seasonally ice-covered area in winter and spring. Here, we use an extensive set of physical and biological ... -
Photophysiological responses of bottom sea-ice algae to fjord dynamics and rapid freshening
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-13)Sea ice algae have a broad salinity tolerance but can experience stress during rapid decreases in salinity that occur with seasonal ice melt and during ice sample melt. This study investigated the impact of salinity on the photophysiological responses of bottom-ice algal communities from two Svalbard fjords (Tempelfjorden and Van Mijenfjorden). To further investigate the impact of salinity alone, ... -
Assessing net primary production in the northwestern Barents Sea using in situ, remote sensing and modelling approaches
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-24)The northwestern Barents Sea (NW-BS) is a highly productive region within the transitional zones of an Atlantic to Arctic-dominated marine ecosystem. The steep latitudinal gradients in sea ice concentration, Atlantic and Arctic Water, offer an opportunity to test hypotheses on physical drivers of spatial and temporal variability of net primary production (NPP). However, quantifying NPP in such a ... -
Development and calibration of a high dynamic range and autonomous ocean-light instrument to measure sub-surface profiles in ice-covered waters
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-23)The optical chain and logger (OptiCAL) is an autonomous ice-tethered observatory equipped with multiple light sensors for mapping the variation of light with depth. We describe the instrument and present an ensemble calibration for downwelling irradiance E<sub>PAR</sub> in [µmolm<sup>−2</sup>s<sup>−1</sup>]. Results from a long-term deployment in the Arctic Ocean demonstrate that the OptiCAL can ... -
Biogeography of microbial communities in high-latitude ecosystems: Contrasting drivers for methanogens, methanotrophs and global prokaryotes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-27)Methane-cycling is becoming more important in high-latitude ecosystems as global warming makes permafrost organic carbon increasingly available. We explored 387 samples from three high-latitudes regions (Siberia, Alaska and Patagonia) focusing on mineral/organic soils (wetlands, peatlands forest), lake/pond sediment and water. Physicochemical, climatic and geographic variables were integrated ... -
Cuscuta campestris fine-tunes gene expression during haustoriogenesis as an adaptation to different hosts
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-14)The Cuscuta genus comprises obligate parasitic plants that have an unusually wide host range. Whether Cuscuta uses different infection strategies for different hosts or whether the infection strategy is mechanistically and enzymatically conserved remains unknown. To address this, we investigated molecular events during the interaction between field dodder (Cuscuta campestris) and two host species ... -
Model-informed classification of broadband acoustic backscatter from zooplankton in an in situ mesocosm
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-07)Classification of zooplankton to species with broadband echosounder data could increase the taxonomic resolution of acoustic surveys and reduce the dependence on net and trawl samples for ‘ground truthing’. Supervised classification with broadband echosounder data is limited by the acquisition of validated data required to train machine learning algorithms (‘classifiers’). We tested the hypothesis ... -
Impacts of a warming climate on concentrations of organochlorines in a fasting high arctic marine bird: Direct vs. indirect effects?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-30)The present study examined how climate changes may impact the concentrations of lipophilic organochlorines (OCs) in the blood of fasting High Arctic common eiders (Somateria mollissima) during incubation. Polychlorinated biphenyls (PCBs), 1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p′-DDE), hexachlorobenzene (HCB) and four chlordane compounds (oxychlordane, trans-chlordane and trans- and ... -
The positive effect of plant diversity on soil carbon depends on climate
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-19)Little is currently known about how climate modulates the relationship between plant diversity and soil organic carbon and the mechanisms involved. Yet, this knowledge is of crucial importance in times of climate change and biodiversity loss. Here, we show that plant diversity is positively correlated with soil carbon content and soil carbon-to-nitrogen ratio across 84 grasslands on six continents ... -
Still Arctic? — The changing Barents Sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-13)The Barents Sea is one of the Polar regions where current climate and ecosystem change is most pronounced. Here we review the current state of knowledge of the physical, chemical and biological systems in the Barents Sea. Physical conditions in this area are characterized by large seasonal contrasts between partial sea-ice cover in winter and spring versus predominantly open water in summer and ... -
Diffusive and advective cross-frontal fluxes of inorganic nutrients and dissolved inorganic carbon in the Barents Sea in autumn
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-21)The Atlantic Water, entering the Arctic through the Barents Sea and Fram Strait, is the main source of nutrients in the Arctic Ocean. The Barents Sea is divided by the Polar Front into an Atlantic-dominated domain in the south, and an Arctic-dominated domain in the north. The Polar Front is a thermohaline structure, which is topographically-steered at sub-surface, and influenced by the seasonal ... -
Hydrography, inorganic nutrients and chlorophyll a linked to sea ice cover in the Atlantic Water inflow region north of Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-04)Changes in the inflow of Atlantic Water (AW) and its properties to the Arctic Ocean bring more warm water, contribute to sea ice decline, promote borealisation of marine ecosystems, and affect biological and particularly primary productivity in the Eurasian Arctic Ocean. One of the two branches of AW inflow follows the shelf break north of Svalbard, where it dominates oceanographic conditions, ... -
Abrupt permafrost thaw triggers activity of copiotrophs and microbiome predators
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-05)Permafrost soils store a substantial part of the global soil carbon and nitrogen. However, global warming causes abrupt erosion and gradual thaw, which make these stocks vulnerable to microbial decomposition into greenhouse gases. Here, we investigated the microbial response to abrupt in situ permafrost thaw. We sequenced the total RNA of a 1 m deep soil core consisting of up to 26 500-year-old permafrost ... -
Atlantification influences zooplankton communities seasonally in the northern Barents Sea and Arctic Ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-29)The Barents Sea is undergoing rapid ocean warming with less sea ice and increased Atlantic inflow, shifting the pelagic ecosystem towards a more boreal one, a process referred to as Atlantification. While such changes have already been documented in the southern and central Barents Sea, less is known about the degree of Atlantification in the northern Barents Sea and Arctic Ocean. In this seasonal ... -
Horizon scanning of potential threats to high-Arctic biodiversity, human health and the economy from marine invasive alien species: A Svalbard case study
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-09)The high Arctic is considered a pristine environment compared with many other regions in the northern hemisphere. It is becoming increasingly vulnerable to invasion by invasive alien species (IAS), however, as climate change leads to rapid loss of sea ice, changes in ocean temperature and salinity, and enhanced human activities. These changes are likely to increase the incidence of arrival and ...