Margot Ulfsdatter Nyeggen

• Farkas, Julia; Piarulli, Stefania; Aune, Marianne; Hansen, Bjørn Henrik; Nordtug, Trond & Sandsæter, Tørris [Vis alle 12 forfattere av denne artikkelen] (2025). Effects of hollow glass microspheres on the benthic and benthopelagic organisms Capitella sp. and Mytilus edulis. Ecotoxicology and Environmental Safety. ISSN 0147-6513. 302, s. 1–10. doi: 10.1016/j.ecoenv.2025.118552. Fulltekst i vitenarkiv Vis sammendrag

  Hollow glass microspheres (HGM) are widely used as fillers in composite materials including paints and plastics. Further, due to their high reflectivity, an approach involving HGM application on Arctic sea ice surfaces has been considered as a measure to reduce ice loss and thus help mitigate climate change effects. In this study we investigated potential impacts of HGMs (average size 47 µm) on two marine species, the benthic polychaete Capitella sp. and the filter feeding blue mussel Mytilus edulis. Capitella were exposed to three concentrations of non-buoyant HGMs with and without sediment (1, 10 and 100 mg g−1 sediment equalling 0.1, 1 and 10 g total HGMs). After a 42 day-exposure (juveniles to adult live stages), HGM uptake, survival and growth were determined. Adult Mytilus edulis were exposed for 10 days to three concentrations (1, 10 and 100 mg L−1) of fresh and biofouled HGMs, and HGM uptake, survival, condition index, clearance rate, cytotoxic and genotoxic damage in haemocytes were analysed. Results show that, while both species ingest HGMs, there were no significant impacts on survival. Exposure to medium and high HGM concentrations in presence and absence of sediment significantly impacted growth and development of Capitella. In contrast, the shorter-term exposure to fresh or biofouled HGMs did not affect the nutritional status, condition index or filtering capacity of adult M. edulis. High concentrations of biofouled HGMs did cause a slight response on cellular level in M. edulis, as eosinophilic cell counts decreased. While responses in M. edulis were less clear, the HGM mode of action on Capitella may be related to alterations in energy budget. Further studies are needed to investigate modes of action and determine effect threshold concentrations in potential target species.

• Ershova, Elizaveta A; Nyeggen, Margot Ulfsdatter; Yurikova, Daria A. & Søreide, Janne E. (2021). Seasonal dynamics and life histories of three sympatric species of Pseudocalanus in two Svalbard fjords. Journal of Plankton Research. ISSN 0142-7873. 43(2), s. 209–223. doi: 10.1093/plankt/fbab007. Fulltekst i vitenarkiv Vis sammendrag

  Small copepods are the most diverse and numerous group in high-latitude zooplankton, yet our knowledge of important species remains poor because of the difficulties involved in correct species identification. In this study, we use a molecular method of identification, a species-specific polymerase chain reaction, to provide the first description of the seasonal dynamics and life histories of the important genus Pseudocalanus in two Svalbard fjords with contrasting environments. We conducted monthly investigations in the relatively warm and ice-free Adventfjorden, supplemented with seasonal samples from the colder, seasonally ice-covered Billefjorden. We found three species of Pseudocalanus (the Arctic P. acuspes and P. minutus, and the boreal P. moultoni). Pseudocalanus acuspes had a distinct annual life cycle and dominated during summer, when it actively reproduced. Surprisingly, the boreal P. moultoni was present year-round in both fjords and was the dominant species during winter; the presence of all life stages of this species throughout the year suggests a more continuous reproduction. The Arctic P. minutus was the rarest of the three species and was likely able to complete its life cycle in Billefjorden but not in Adventfjorden. Our study demonstrates that closely related species may have different life strategies and environmental preferences, which presumably make high-latitude zooplankton communities more resilient to climate change impacts on genus but not necessarily on species level.

Se alle arbeider i NVA

• Nyeggen, Margot Ulfsdatter; Christiansen, Svenja; Garvang, Even Sletteng; Andersen, Tom; Heuschele, Jan David & Titelman, Josefin (2025). Zooplankton community dynamics in Oslofjorden. Fulltekst i vitenarkiv
• Heuschele, Jan David; Nyeggen, Margot Ulfsdatter & Titelman, Josefin (2024). Ecotaxa ID 15537, Continuous Particle Imaging and Classification System (CPICS) images. doi: https:/ecotaxa.obs-vlfr.fr/prj/15537. Fulltekst i vitenarkiv

Se alle arbeider i NVA