stefanka

• Barrio, Isabel C.; Vuorinen, Katariina Elsa M; Barbero-Palacios, Laura; Defourneaux, Mathilde; Bon, Matteo Petit & Greer, Eleanor [Vis alle 79 forfattere av denne artikkelen] (2025). Emerging priorities in terrestrial herbivory research in the Arctic. Arctic Science. ISSN 2368-7460. 11, s. 1–26. doi: 10.1139/as-2024-0080. Fulltekst i vitenarkiv Vis sammendrag

  Herbivores are an integral part of Arctic terrestrial ecosystems, driving ecosystem functioning and sustaining local livelihoods. In the context of accelerated climate warming and land use changes, understanding how herbivores contribute to the resilience of Arctic socio-ecological systems is essential to guide sound decision-making and mitigation strategies. While research on Arctic herbivory has a long tradition, recent literature syntheses highlight important geographical, taxonomic, and environmental knowledge gaps on the impacts of herbivores across the region. At the same time, climate change and limited resources impose an urgent need to prioritize research and management efforts. We conducted a horizon scan within the Arctic herbivory research community to identify emerging scientific and management priorities for the next decade. From 288 responses received from 85 participants in two online surveys and an in-person workshop, we identified 8 scientific and 8 management priorities centred on (a) understanding and integrating fundamental ecological processes across multiple scales from individual herbivore–plant interactions up to regional and decadal scale vegetation and animal population effects; (b) evaluating climate change feedbacks; and (c) developing new research methods. Our analysis provides a strategic framework for broad, inclusive, interdisciplinary collaborations to optimise terrestrial herbivory research and sustainable management practices in a rapidly changing Arctic.

• Kamenova, Stefaniya Kamenova; Albon, Steve D.; Loe, Leif Egil; Irvine, R. Justin; Langvatn, Rolf & Gusarova, Galina [Vis alle 8 forfattere av denne artikkelen] (2025). Arctic Greening Drives Changes in the Diet and Gut Microbiome of a Large Herbivore With Consequences for Body Mass. Ecology and Evolution. 15(7). doi: 10.1002/ece3.71731. Fulltekst i vitenarkiv Vis sammendrag

  Rapid climate warming is ‘greening’ the tundra, reflecting a higher plant biomass, particularly of deciduous shrubs and grasses. However, the consequences of these changes for herbivore nutrition are unclear. Although, the gut microbiome mediates nutrient metabolism, and hence herbivores' capacity to adapt to dietary change, few studies have investigated the effect of annual changes in the diet-gut microbiome nexus on fitness-related traits. In a model system, the Svalbard reindeer, a species experiencing the greatest rate of climate warming on Earth, we investigate how changes in diet and the gut microbiome impact reindeer body mass. Using high-resolution DNA metabarcoding, we assessed diet and gut microbiome bacterial composition in rumen samples from animals culled in October from 1998 to 2004 in four different valleys. Overall diet diversity and grass relative reads abundance (RRA) were significantly higher following warmer summers, while the RRA of the dwarf shrub Salix polaris increased with the maximum normalised difference vegetation index (NDVI), our measure of annual biomass. Autumn body mass, a strong proxy of fitness in Svalbard reindeer, was significantly, positively correlated with Salix RRA, most pronounced in females that had reproduced, and by that depleted body reserves. Multivariate analyses revealed a highly significant relationship between diet and microbiome composition at the individual level. This included a significant positive correlation between Salix and bacterial diversity. However, a structural equation model revealed that the direct path effect of Salix on reindeer body mass was stronger than the indirect path effect, mediated through the gut microbiome. Our results suggest that climate-driven Arctic greening may have implications for herbivore body mass, operating through a change in diet composition. These findings reveal some of the mechanistic underpinnings of Arctic warming on herbivore populations and highlight the importance of the diet−gut microbiome nexus in facilitating species resilience to rapid climate change.

• Neby, Magne; Ims, Rolf Anker; Kamenova, Stefaniya Kamenova; Devineau, Olivier & Soininen, Eeva Marjatta (2024). Is the diet cyclic phase-dependent in boreal vole populations? Ecology and Evolution. 14(4). doi: 10.1002/ece3.11227. Fulltekst i vitenarkiv Vis sammendrag

  Herbivorous rodents in boreal, alpine and arctic ecosystems are renowned for their multi-annual population cycles. Researchers have hypothesised that these cycles may result from herbivore–plant interactions in various ways. For instance, if the biomass of preferred food plants is reduced after a peak phase of a cycle, rodent diets can be expected to become dominated by less preferred food plants, leading the population to a crash. It could also be expected that the taxonomic diversity of rodent diets in creases from the peak to the crash phase of a cycle. The present study is the first to use DNA metabarcoding to quantify the diets of two functionally important boreal rodent species (bank vole and tundra vole) to assess whether their diet changed sys tematically in the expected cyclic phase-dependent manner. We found the taxonomic diet spectrum broad in both vole species but with little interspecific overlap. There was no evidence of systematic shifts in diet diversity metrics between the phases of the population cycle in either species. While both species' diet composition changed moderately between cycle phases and seasons, these changes were small compared to other sources of diet variation—especially differences between individuals. Thus, the variation in diet that could be attributed to cyclic phases is marginal relative to the overall diet flexibility. Based on general consumer-resource theory, we suggest that the broad diets with little interspecific overlap render it unlikely that herbivore–plant interactions generate their synchronous population cycles. We propose that deter mining dietary niche width should be the first step in scientific inquiries about the role of herbivore–plant interactions in cyclic vole populations.

• Evangelista, Charlotte; Kamenova, Stefaniya; Pauli, Beatriz Diaz; Sandkjenn, Joakim; Vøllestad, Leif Asbjørn & Edeline, Eric [Vis alle 8 forfattere av denne artikkelen] (2023). Within-species variation in the gut microbiome of medaka (Oryzias latipes) is driven by the interaction of light intensity and genetic background. Peer Community Journal. 3. doi: 10.24072/pcjournal.306. Fulltekst i vitenarkiv Vis sammendrag

  Unravelling evolution-by-environment interactions on the gut microbiome is particularly relevant considering the unprecedented level of human-driven disruption of the ecological and evolutionary trajectories of species. Here, we aimed to evaluate whether an evolutionary response to size-selective mortality influences the gut microbiome of medaka (Oryzias latipes), how environmental conditions interact with the genetic background of medaka on their microbiota, and the association between microbiome diversity and medaka growth-related traits. To do so, we studied two lineages of medaka with known divergence in foraging efficiency and life history raised under antagonistic size-selective regimes for 10 generations (i.e. the largest or the smallest breeders were removed to mimic fishing-like or natural mortality). In pond mesocosms, the two lineages were subjected to contrasting population density and light intensity (used as proxies of resource availability). We observed significant differences in the gut microbiome composition and richness between the two lines, and this effect was mediated by light intensity. The bacterial richness of fishing-like medaka (small-breeder line) was reduced by 34% under low-light conditions compared to high-light conditions, while it remained unchanged in natural mortality-selected medaka (large-breeder line). However, the observed changes in bacterial richness did not correlate with changes in adult growth-related traits. Given the growing evidence about the gut microbiomes importance to host health, more in-depth studies are required to fully understand the role of the microbiome in size-selected organisms and the possible ecosystem-level consequences.

• Davey, Marie Louise; Kamenova, Stefaniya; Fossøy, Frode; Solberg, Erling Johan; Davidson, Rebecca K. & Mysterud, Atle [Vis alle 7 forfattere av denne artikkelen] (2023). Faecal metabarcoding provides improved detection and taxonomic resolution for non-invasive monitoring of gastrointestinal nematode parasites in wild moose populations. Parasites & Vectors. 16(1). doi: 10.1186/s13071-022-05644-6. Fulltekst i vitenarkiv Vis sammendrag

  Background Although wild ungulate populations are heavily monitored throughout Europe, we understand little of how parasites afect population dynamics, and there is no systematic, long-term monitoring of parasite diversity and parasite loads. Such monitoring is in part hampered by a lack of time- and cost-efective assay methodologies with high sensitivity and good taxonomic resolution. DNA metabarcoding has been successfully used to characterize the parasitic nemabiome with high taxonomic resolution in a variety of wild and domestic hosts. However, in order to implement this technique in large-scale, potentially non-invasive monitoring of gastrointestinal parasitic nematodes (GIN), protocol optimization is required to maximize biodiversity detection, whilst maintaining time- and cost-efectiveness. Methods Faecal samples were collected from a wild moose population and GIN communities were characterized and quantifed using both parasitological techniques (egg and larva counting) and DNA metabarcoding of the ITS2 region of rDNA. Three diferent isolation methods were compared that difered in the volume of starting material and cell lysis method. Results Similar nematode faunas were recovered from all samples using both parasitological and metabarcoding methods, and the approaches were largely congruent. However, metabarcoding assays showed better taxonomic resolution and slightly higher sensitivity than egg and larvae counts. The metabarcoding was not strictly quantitative, but the proportion of target nematode sequences recovered was correlated with the parasitologically determined parasite load. Species detection rates in the metabarcoding assays were maximized using a DNA isolation method that included mechanical cell disruption and maximized the starting material volume. Conclusions DNA metabarcoding is a promising technique for the non-invasive, large-scale monitoring of parasitic GINs in wild ungulate populations, owing to its high taxonomic resolution, increased assay sensitivity, and time- and cost-efectiveness. Although metabarcoding is not a strictly quantitative method, it may nonetheless be possible to create a management- and conservation-relevant index for the host parasite load from this data. To optimize the detection rates and time- and cost-efectiveness of metabarcoding assays, we recommend choosing a DNA isolation method that involves mechanical cell disruption and maximizes the starting material volume. Nemabiome, Metabarcoding, ITS2, DNA extraction method, NC1–NC2 primers, Alces alces, Helminth, Ungulates

• Kamenova, Stefaniya; Muinck, Eric de; Veiberg, Vebjørn; Utsi, Tove Hilde Ågnes; Steyaert, Sam & Albon, Steve [Vis alle 8 forfattere av denne artikkelen] (2023). Gut microbiome biogeography in reindeer supersedes millennia of ecological and evolutionary separation. FEMS Microbiology Ecology. ISSN 0168-6496. 99(12). doi: 10.1093/femsec/fiad157. Fulltekst i vitenarkiv Vis sammendrag

  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 strong spatial structuring, and pronounced differences in microbial diversity of at least 33 phyla across the stomach, small intestine, and large intestine (including faeces). The main structural feature was the Bacteroidota to Firmicutes ratio, which declined from the stomach to the large intestine, likely reflecting functional adaptation. Metagenome shotgun sequencing also revealed highly significant structuring in the relative occurrence of carbohydrate-active enzymes (CAZymes). CAZymes were enriched in the rumen relative to the small and large intestines. Interestingly, taxonomic diversity was highest in the large intestine, suggesting an important and understudied role for this organ. Despite the two study populations being separated by an ocean and six millennia of evolutionary history, gut microbiome structuring was remarkably consistent. Our study suggests a strong selection for gut microbiome biogeography along the gastrointestinal tract in reindeer subspecies.

• Soininen, Eeva M; Barrio, Isabel C.; Bjørkås, Ragnhild; Björnsdóttir, Katrin; Ehrich, Dorothee & Hopping, Kelly A. [Vis alle 44 forfattere av denne artikkelen] (2021). Location of studies and evidence of effects of herbivory on Arctic vegetation: a systematic map. Environmental Evidence. 10(25). doi: 10.1186/s13750-021-00240-0. Fulltekst i vitenarkiv Vis sammendrag

  Herbivores modify the structure and function of tundra ecosystems. Understanding their impacts is necessary to assess the responses of these ecosystems to ongoing environmental changes. However, the effects of herbivores on plants and ecosystem structure and function vary across the Arctic. Strong spatial variation in herbivore effects implies that the results of individual studies on herbivory depend on local conditions, i.e., their ecological context. An important first step in assessing whether generalizable conclusions can be produced is to identify the existing studies and assess how well they cover the underlying environmental conditions across the Arctic. This systematic map aims to identify the ecological contexts in which herbivore impacts on vegetation have been studied in the Arctic. Specifically, the primary question of the systematic map was: “What evidence exists on the effects of herbivores on Arctic vegetation?”.

• Neby, Magne; Kamenova, Stefaniya; Devineau, Olivier; Ims, Rolf Anker & Soininen, Eeva M (2021). Issues of under-representation in quantitative DNA metabarcoding weaken the inference about diet of the tundra vole Microtus oeconomus. PeerJ. 9. doi: 10.7717/peerj.11936. Fulltekst i vitenarkiv Vis sammendrag

  During the last decade, methods based on high-throughput sequencing such as DNA metabarcoding have opened up for a range of new questions in animal dietary studies. One of the major advantages of dietary metabarcoding resides in the potential to infer a quantitative relationship between sequence read proportions and biomass of ingested food. However, this relationship’s robustness is highly dependent on the system under study, calling for case-specific assessments. Herbivorous small rodents often play important roles in the ecosystem, and the use of DNA metabarcoding for analyses of rodent diets is increasing. However, there has been no direct validation of the quantitative reliability of DNA metabarcoding for small rodents. Therefore, we used an experimental approach to assess the relationship between input plant biomass and sequence reads proportions from DNA metabarcoding in the tundra vole Microtus oeconomus. We found a weakly positive relationship between the number of high-throughput DNA sequences and the expected biomass proportions of food plants. The weak relationship was possibly caused by a systematic under-amplification of one of the three plant taxa fed. Generally, our results add to the growing evidence that case-specific validation studies are required to reliably make use of sequence read abundance as a proxy of relative food proportions in the diet.

• Kamenova, Stefaniya; Bretagnolle, Vincent; Plantegenest, Manuel & Canard, Elsa (2018). DNA metabarcoding diet analysis reveals dynamic feeding behaviour and biological control potential of carabid farmland communities. BioRxiv. ISSN 0362-4331. Fulltekst i vitenarkiv
• Kamenova, Stefaniya; Mayer, Rebecca; Rubbmark, Oskar R.; Coissac, Eric; Plantegenest, Manuel & Traugott, Michael (2018). Comparing three types of dietary samples for prey DNA decay in an insect generalist predator. Molecular Ecology Resources. ISSN 1755-098X. doi: 10.1111/1755-0998.12775. Fulltekst i vitenarkiv

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• Gusarova, Galina; Mjøen, Hedvig Elisabeth; Corti, Magali; Mahé, Frédéric; Meyer, Pernille & Steinthorsdottir, Lilja [Vis alle 22 forfattere av denne artikkelen] (2024). Bridging past and present: From dietary metabarcoding of large herbivores towards broad scale biodiversity analyses. Fulltekst i vitenarkiv
• Johaadien, Rukaya Sarah; Frøslev, Tobias Guldberg; Plessis, Morne Du; Torma, Michal; Kamenova, Stefaniya & Braathen, Catherine [Vis alle 7 forfattere av denne artikkelen] (2023). Course on DNA barcode data in BOLD and GBIF - Cape Town, South Africa. Fulltekst i vitenarkiv Vis sammendrag

  Accelerating biodiversity research through DNA barcodes, collection, and observation data. Regional Training Course for M.Sc. and Ph.D. students with expert trainers and trainers-in-training - Cape Town, South Africa.

• Soininen, Eeva M; Barrio, Isabel C.; Bjørkås, Ragnhild; Björnsdóttir, Katrín; Ehrich, Dorothee & Hopping, Kelly [Vis alle 44 forfattere av denne artikkelen] (2022). Correction to: Location of studies and evidence of effects of herbivory on Arctic vegetation: a systematic map (Environmental Evidence, (2021), 10, 1, (25), 10.1186/s13750-021-00240-0). Environmental Evidence. 11(1). doi: 10.1186/s13750-022-00265-z. Fulltekst i vitenarkiv
• Kamenova, Stefaniya; Boer, Hugo de; Endresen, Dag; Russell, Laura Anne; Schigel, Dmitry & Wirta, Helena K (2021). Accelerating biodiversity research through DNA barcodes, collection and observation data (online for Georgia and Armenia June 2021). Fulltekst i vitenarkiv Vis sammendrag

  This course will teach how to use DNA barcodes, collection and observation data to resolve research questions in biodiversity. The four-day intensive programme will use a combination of lectures, tutorials, and hands-on exercises. You will learn to handle biodiversity data including DNA barcoding. You will gain practical experience in using open and digitally documented biodiversity data through GBIF and BOLD to answer biodiversity research questions. You will understand and practice capturing observation, collection, and genetic data from analogue and digital sources. Finally, the course provides basic skills in data publishing through GBIF. This course is a collaboration between the Diku-funded University of Oslo project BioDATA, the BMBF-funded project Caucasus Barcode of Life (CaBOL), and GBIF - Global Biodiversity Information Facility.

• Gusarova, Galina; Kamenova, Stefaniya; Coissac, Eric; Meyer, Pernille; Steinthorsdottir, Lilja & Loe, Leif Egil [Vis alle 14 forfattere av denne artikkelen] (2019). Multi-locus DNA metabarcoding of diet provides new insights into the ecology and trophic interactions of a keystone herbivore species. Fulltekst i vitenarkiv
• Kamenova, Stefaniya (2018). REININ project: Reindeer interactions from plants and birds to humans: balancing the odds of climate change. Fulltekst i vitenarkiv
• Kamenova, Stefaniya (2017). REININ project: Reindeer interactions from plants and birds to humans: Balancing the odds of climate change. Fulltekst i vitenarkiv

Se alle arbeider i NVA