My research is on seaweeds. Seaweeds are very important primary producers in the coastal area, they form habitats for myriads of associated animals, they can function as devices for measuring levels of heavy metals in the environment, and they can be harvested or cultured for food or valuable biochemical components such as agar and alginate. My main interests are seaweed ecology, and how seaweeds evolve and adapt to the environment. Some of the topics I study:

-        Evolution, morphological variation and speciation processes in the genus Fucus

-        Effects of invasive seaweeds on indigenous coastal communities

-        Changes in seaweed communities due to environmental impact and climate changes

BIO309 Marine floristics

BIO212 Marine Community Ecology - Organisms and Habitats

BIO101 Organismebiologi 1

Poster

• Ruiz Martinez, Eliana; Larsen, Aud; Sandaa, Ruth-Anne et al. (2024). Phaeoviruses present in cultured and natural kelp species, Saccharina latissima and Laminaria hyperborea (Phaeophyceae, Laminariales), in Norway.. (external link)
• Valero-Rodriguez, Juan M; Sjøtun, Kjersti; Barouti, Angeliki et al. (2024). Effects of climate change on herbivory in macroalgae: a laboratory experiment. (external link)
• Sjøtun, Kjersti; Fredriksen, Stein; Gabrielsen, Tove M. et al. (2023). Mapping and DNA barcoding the brown algal diversity within the orders Ectocarpales, Ralfsiales and Sphacelariales in Norway. (external link)
• Enerstvedt, Kjersti Hasle; Jordheim, Monica; Andersen, Øyvind M et al. (2016). Analysis of Flavonoids in the Seagrass Zostera Marina L.. (external link)

Academic article

• van der Loos, Luna M.; Bafort, Quinten; Bosch, Samuel et al. (2024). Non-indigenous seaweeds in the Northeast Atlantic Ocean, the Mediterranean Sea and Macaronesia: a critical synthesis of diversity, spatial and temporal patterns. (external link)
• Ruiz Martinez, Eliana; Mckeown, Dean A.; Schroeder, Decland C. et al. (2023). Phaeoviruses Present in Cultured and Natural Kelp Species, Saccharina latissima and Laminaria hyperborea (Phaeophyceae, Laminariales), in Norway. (external link)
• Ribeiro, Pedro Miguel de Azevedo; Næss, Tonje; Dahle, Geir et al. (2022). Going With the Flow – Population Genetics of the Kelp Saccharina latissima (Phaeophyceae, Laminariales). (external link)
• Hatchett, William John; Coyer, James A.; Sjøtun, Kjersti et al. (2022). A review of reproduction in the seaweed genus Fucus (Ochrophyta, Fucales): Background for renewed consideration as a model organism. (external link)
• Sjøtun, Kjersti; Armitage, Caroline Susanne; Eilertsen, Mette et al. (2021). Fauna associated with non-native Sargassum muticum (Fucales, Phaeophyceae) vary with thallus morphology and site type (sounds and bays). (external link)
• Thomson, Alex Innes; Archer, Frederick I.; Coleman, Melinda Ann et al. (2021). Charting a course for genetic diversity in the UN Decade of Ocean Science. (external link)
• Sandvik, Hanno; Hilmo, Olga; Henriksen, Snorre et al. (2020). Alien species in Norway: Results from quantitative ecological impact assessments. (external link)
• Bringloe, Trevor T; Sjøtun, Kjersti; Saunders, Gary W (2019). A DNA barcode survey of marine macroalgae from Bergen (Norway). (external link)
• Sandvik, Hanno; Dolmen, Dag; Elven, Reidar et al. (2019). Alien plants, animals, fungi and algae in Norway: an inventory of neobiota. (external link)
• Bjordal, Mari Vold; Jensen, Knut Helge; Sjøtun, Kjersti (2019). A field study of the edible red alga Vertebrata lanosa (Rhodophyta). (external link)
• Enerstvedt, Kjersti Hasle; Lundberg, Anders; Sjøtun, Kjersti et al. (2017). Characterization and seasonal variation of individual flavonoids in Zostera marina and Zostera noltii from Norwegian coastal waters. (external link)
• Armitage, Caroline Susanne; Husa, Vivian; Petelenz-Kurdziel, Elzbieta Anna et al. (2017). Growth and competition in a warmer ocean: A field experiment with a non-native and two native habitat-building seaweeds. (external link)
• Armitage, Caroline Susanne; Sjøtun, Kjersti (2017). Can an old alien benefit from rising ocean temperatures? An experimental and field study on the growth and local distribution of Codium fragile subsp. fragile (Chlorophyta). (external link)
• Sjøtun, Kjersti; Heesch, Svenja; Lluch, Jordi Rull et al. (2017). Unravelling the complexity of salt marsh ‘Fucus cottonii’ forms (Phaeophyceae, Fucales). (external link)
• Armitage, Caroline Susanne; Sjøtun, Kjersti (2016). Codium fragile in Norway: subspecies identity and morphology. (external link)
• Armitage, Caroline Susanne; Sjøtun, Kjersti (2016). Epiphytic macroalgae mediate the impact of a non-native alga on associated fauna. (external link)
• Sjøtun, Kjersti; Heggøy, Erling; Gabrielsen, Tove M. et al. (2016). Dasya adela sp. nov. (Rhodophyta, Ceramiales), an enigmatic new Dasya from a landlocked fjord in southwest Norway. (external link)
• Sjøtun, Kjersti; Husa, Vivian; Asplin, Lars et al. (2015). Climatic and environmental factors influencing occurrence and distribution of macroalgae – a fjord gradient revisited. (external link)
• Husa, Vivian; Kutti, Tina; Ervik, Arne S et al. (2014). Regional impact from fin-fish farming in an intensive production area (Hardangerfjord, Norway). (external link)
• Husa, Vivian; Steen, Henning; Sjøtun, Kjersti (2014). Historical changes in macroalgal communities in Hardangerfjord (Norway). (external link)
• Armitage, Caroline Susanne; Sjøtun, Kjersti; Jensen, Knut Helge (2014). Correlative evidence for competition between fucus serratus and the introduced chlorophyte codium fragile subsp. fragile on the southwest coast of norway. (external link)
• Bengtsson, Mia M. B.; Sjøtun, Kjersti; Lanzén, Anders et al. (2012). Bacterial diversity in relation to secondary production and succession on surfaces of the kelp Laminaria hyperborea. (external link)
• Sjøtun, Kjersti; Heldal, Hilde Elise; Brakstad, Daniela Sabine (2011). Differential concentration of Technetium-99 (99Tc) in common intertidal molluscs with different food habits. (external link)
• Eilertsen, Mette; Norderhaug, Kjell Magnus; Sjøtun, Kjersti (2011). Does the amphipod fauna associated with epiphytes on kelp (Laminaria hyperborea) change with depth?. (external link)
• Bengtsson, Mia M. B.; Sjøtun, Kjersti; Storesund, Julia Endresen et al. (2011). Utilization of kelp-derived carbon sources by kelp surface-associated bacteria. (external link)
• Bengtsson, Mia M. B.; Sjøtun, Kjersti; Øvreås, Lise (2010). Seasonal dynamics of bacterial biofilms on the kelp Laminaria hyperborea. (external link)
• Heldal, Hilde Elise; Sjøtun, Kjersti (2010). Technetium-99 (Tc-99) in annual growth segments of knotted wrack (Ascophyllum nodosum). (external link)
• Lorentsen, Svein Håkon; Sjøtun, Kjersti; Grémillet, David (2010). Multi-trophic consequences of kelp harvest. (external link)
• Husa, Vivian; Sjøtun, Inga Kjersti; Brattenborg, Narve et al. (2008). Changes of macroalgal biodiversity in sublittoral sites in southwest Norway: impact of an introduced species or higher temperature?. (external link)
• Coyer, James A.; Hoarau, Galice; Sjøtun, Inga Kjersti et al. (2008). Being abundant is not enough: a decrease in effective population size over eight generations in a Norwegian population of the seaweed, Fucus serratus. (external link)
• Sjøtun, Inga Kjersti; Husa, Vivian; Peña, Viviana (2008). Present distribution and possible vectors of introductions of the alga Heterosiphonia japonica (Ceramiales, Rhodophyta) in Europe. (external link)
• Rueness, Jan; Heggøy, Erling; Husa, Vivian et al. (2007). First report of the Japanese red alga Antithamnion nipponicum (Ceramiales, Rhodophyta) in Norway, an invasive species new to northern Europe. (external link)
• Sjøtun, Kjersti; Eggereide, Sarah Fagertun; Høisæter, Tore (2007). Grazer-controlled recruitment of the introduced Sargassum muticum (Phaeophyceae, Fucales) in northern Europe. (external link)
• Sjøtun, Kjersti; Christie, Hartvig; Fosså, Jan Helge (2006). The combined effect of canopy shading and sea urchin grazing on recruitment in kelp forest (Laminaria hyperborea). (external link)
• Husa, Vivian; Sjøtun, Kjersti (2006). Vegetative reproduction in "Heterosiphonia japonica" (Dasyaceae, Ceramiales), an introduced red alga on European coasts. (external link)
• Rinde, Eli; Sjøtun, Kjersti (2005). Demographic variation in the kelp Laminaria hyperborea along a latitudinal gradient. (external link)
• Husa, Vivian; Sjøtun, Kjersti; Lein, Tor Eiliv (2004). The newly introduced species Heterosiphonia japonica Yendo (Dasyaceae, Rhodophyta): geographical distribution and abundance at the Norwegian southwest coast. (external link)
• Husa, V; Sjøtun, Kjersti; Lein, TE (2004). The newly introduced species Heterosiphonia japonica Yendo (Dasyaceae, Rhodophyta): geographical distribution and abundance at the Norwegian southwest coast. (external link)

Report

• Nøkling-Eide, Katharina; Sjøtun, Kjersti; Rueness, Jan et al. (2022). BESTEMMELSESNØKLER TIL NORSKE MARINE MAKROALGER 4. METODER, ORDFORKLARINGER OG ARTSREGISTER. (external link)
• Nielsen, Anders; Fossen, Torgils; Gjershaug, Jan Ove et al. (2017). Assessment of the potential connection between Tilia trees and bumblebee Death. Opinion of the Panel on Alien organisms and trade in endangered species (CITES) of the Norwegian Scientific Committee for Food Safety. (external link)
• Rueness, Eli Knispel; Cadahia-Lorenzo, Luis; Hoel, Kristian et al. (2017). Assessment of the risks associated with the import and release of hand-reared mallards for hunting purposes. Opinion of the Panel on Alien Organisms and Trade in Endangered Species (CITES) of the Norwegian Scientific Committee for Food Safety. (external link)
• de Boer, Hugo; Asmyhr, Maria Gulbrandsen; Grundt, Hanne Hegre et al. (2016). Assessment of the risks to Norwegian biodiversity from the import and keeping of aquarium and garden pond plants. Opinion of the Panel on Alien Organisms and Trade in Endangered Species (CITES) of the Norwegian Scientific Committee for Food Safety. (external link)
• Rueness, Eli Knispel; Asmyhr, Maria Gulbrandsen; Endrestøl, Anders et al. (2016). Assessment of species listing proposals for CITES CoP17. Opinion of the Panel on Alien Organisms and Trade in Endangered Species (CITES) of the Norwegian Scientific Committee for Food Safety. (external link)
• Nielsen, Anders; Finne, Merethe Aasmo; Asmyhr, Maria Gulbrandsen et al. (2016). Assessment of the risks to Norwegian biodiversity from the import and keeping of terrestrial arachnids and insects. Opinion of the Panel on Alien Organisms and Trade in Endangered species of the Norwegian Scientific Committee for Food Safety. (external link)
• Fredriksen, Stein; Sjøtun, Kjersti (2015). Risikovurdering ved utseting av ikke-stedegen tare. (external link)
• Oug, Eivind; Bjørge, Arne Jostein; Gjøsæter, Jakob et al. (2013). Utvikling av indikatoren «sårbare og truete arter» for Nordsjøen, Norskehavet og Barentshavet. En oversikt over forekomst og kunnskapsgrunnlag for truete arter og ansvarsarter i norske sjøområder. (external link)
• Husa, Vivian; Heggøy, Erling; Sjøtun, Kjersti et al. (2012). Kartlegging av fremmede marine arter i Hordaland. (external link)
• Fredriksen, Stein; Skjoldal, HR; Husa, Vivian et al. (2011). Vurdering av eutrofisituasjonen i kystområder, med særlig fokus på Hardangerfjorden og Boknafjorden. (external link)
• Sjøtun, Kjersti; Olsen, Bernt Rydland; Eggereide, Sarah Fagertun (2004). Biomass survey of Laminaria digitata in the Smøla area. (external link)

Database

• Sandvik, Hanno; Hilmo, Olga; Henriksen, Snorre et al. (2020). Data from: Ecological impact assessments of alien species in Norway. (external link)

Lecture

• Handå, Aleksander; Broch, Ole Jacob; Forbord, Silje et al. (2019). MACROSEA - A knowledge Platform for Industrial Macroalgae Cultivation. (external link)
• Handå, Aleksander; Broch, Ole Jacob; Forbord, Silje et al. (2018). Taredyrking – en næring i vekst. (external link)

Academic anthology/Conference proceedings

• Salvanes, Anne Gro Vea; Devine, Jennifer Ann; Jensen, Knut Helge et al. (2018). Marine Ecological Field Methods - A guide for marine biologists and fisheries scientists. (external link)

Academic chapter/article/Conference paper

• Hestetun, Jon Thomassen; Sjøtun, Kjersti; Aksnes, Dag Lorents et al. (2018). The marine Environment. (external link)
• Salvanes, Anne Gro Vea; Glenner, Henrik; Aksnes, Dag Lorents et al. (2018). Sampling gears and equipment. (external link)
• Devine, Jennifer Ann; Ferter, Keno; Glenner, Henrik et al. (2018). Planning marine field studies. (external link)
• Salvanes, Anne Gro Vea; Glenner, Henrik; Devine, Jennifer Ann et al. (2018). Sorting specimens and preserving materials. (external link)
• Jensen, Knut Helge; Devine, Jennifer Ann; Glenner, Henrik et al. (2018). Data analysis. (external link)
• Rueness, Jan; Bjærke, Marit Ruge; Fredriksen, Stein et al. (2006). Alger - Cynanophyta, Rhodophyta, Phaeophyceae, Ulvophyceae, Charophyceae. (external link)

Doctoral dissertation

• Armitage, Caroline Susanne; Sjøtun, Kjersti (2017). Codium fragile subsp. fragile and Sargassum muticum: Non-native seaweeds in a changing environment. (external link)
• Sjøtun, Inga Kjersti (1995). Adaptive aspects of growth and reproduction in two North Atlantic Laminaria species. -Dr. scient. Thesis. (external link)

Chapter

• Fredriksen, Stein; Moy, Frithjof Emil; Husa, Vivian et al. (2015). Alger Cyanophyta, Rhodophyta, Chlorophyta, Ochrophyta. (external link)
• Sjøtun, Kjersti; Fredriksen, Stein; Heggøy, Erling et al. (2010). Alger: Cyanophyta, rhodophyta, chlorophyta, ochrophyta. (external link)

Editorial

• Skaala, Øystein; Sjøtun, Kjersti; Dahl, Einar et al. (2014). Interactions between salmon farming and the ecosystem: Lessons from the Hardangerfjord, western Norway. (external link)
• Høisæter, Tore; Brattegard, Torleiv; Sjøtun, Kjersti (2011). Norwegian fjords: From natural history to ecosystem ecology and beyaond. (external link)
• Brattegard, Torleiv; Høisæter, Tore; Sjøtun, Kjersti et al. (2011). Norwegian fjords: from natural history to ecosystem ecology and beyond. (external link)

Abstract

• Skage, Morten; Mikkelsen, Nina Therese; Sjøtun, Inga Kjersti (2009). GENETIC SEPARATION OF DIFFERENT ENTITIES OF MASTOCARPUS STELLATUS (STACKHOUSE) GUIRY. (external link)

Masters thesis

• Eilertsen, Mette; Sjøtun, Inga Kjersti; Norderhaug, Kjell Magnus (2007). Does the composition of amphipods associated to epiphytes on kelp (Laminaria hyperborea) change with depth?. (external link)
• Rønningen, Vera; Sjøtun, Kjersti (2006). The survival and viability of Saccharina latissima ((L.) Lane, Mayes, Druehl et Saunders) spores and microscopic sporophytes in temperatures of 18-22°C. (external link)

Thesis at a second degree level

• Helle, Angelfoss; Sjøtun, Kjersti (2005). Opptak og lagring av ammonium hos Fucus serratus (L.) og Cladophora rupestris (L.) Kütz. (external link)

Academic lecture

• Olsen, Bernt Rydland; Sjøtun, Kjersti; Høisæter, Tore et al. (2004). Population structure of Laminaria digitata (Hudson) J.V. Lamouroux from three different areas in the Northeast Atlantic Ocean. (external link)

See a complete overview of publications in Cristin.

Ribeiro PA, Næss T, Dahle G, Asplin L, Meland K, Fredriksen S, Sjøtun K (2022). Going with the flow - population genetics of the kelp Saccharina latissima (Phaeophyceae, Laminariales). Frontiers in Marine Science DOI 10.3389/fmars.2022.876420

Sjøtun K, Armitage CS, Eilertsen M, Todt C (2021). Fauna associated with non-native Sargassum muticum (Fucales, Phaeophyceae) vary with thallus morphology and site type (sounds and bays). Marine Biological Research DOI 10.1080/17451000.2021.1994999

Thomson et al. (2021). Charting a course for genetic diversity in the UN Decade of Ocean Science. Evolutionary Applications httP://doi.org/10.1111/eva.13224

Sandvik et al. (2020). Alien species in Norway: results from quantitative ecological impact assessments. Ecological Solutions and Evidence 1 10.1002/2688-8319.12006

Sandvik H et al. (2019). Alien plants, fungi and algae in Norway: an inverntory of neobiota. Biological Invasions 21: 2997-3012

Bringloe TT, Sjøtun K, Saunders GW (2019). A DNA barcode survey of marine macroalgae from Bergen (Norway). Marine Biology Research https://doi.org/10.1080/17451000.2019.1699659

Bjordal MV, Jensen KH, Sjøtun K (2019). A field study of the edible red alga Vertebrata lanosa (Rhodophyta). Journal of Applied Phycology in press.

Enerstvedt KH, Lundberg A, Sjøtun IK, Fadnes P, Jordheim M (2017). Characterization and seasonal variation of Individual flavonoids in Zostera marina and Zostera noltii from Norwegian coastal waters. Biochemical Systematics and Ecology 74:    42-50

Armitage CS, Sjøtun K (2017). Can an old alien benefit from rising ocean temperatures? An experimental and field study on the growth and local distribution of Codium fragile subsp. fragile (Chlorophyta). Marine Biology DOI 10.1007/s00227-017-3170-5

Armitage CS, Husa V, Petelenz-Kurdziel EA, Sjøtun K (2017). Growth and competition in a warmer ocean: A field experiment with a non-native and two native habitat building seaweeds. Marine ecology Progress Series 573: 85–99

Sjøtun K, Heesch S, Rull Lluch J, Martín Martín R, Gómez Garreta A, Brysting AK, Coyer JA (2017). Unraveling the complexity of salt marsh "Fucus cottonii" forms (Phaeophyceae, Fucales). European Journal of Phycology             doi.org/10.1080/09670262.2017.1309688

Armitage CS, Sjøtun K (2016). Codium fragile in Norway: Subspecies identity and morphology. Botanica Marina 56: 439–450

Armitage CS, Sjøtun K (2016). Epiphytic macroalgae mediate the impact of a non-native algae on associated fauna. Hydrobiologia DOI 10.1007/s10750-016-2707-9

Sjøtun K, Heggøy E, Gabrielsen TM, Rueness J (2016). Dasya adela sp. nov. (Rhodophyta, Ceramiales), an enigmatic new Dasya from a landlocked fjord in southwest Norway. Phycological Research 64: 79-94 

Sjøtun K, Husa V, Asplin L, Sandvik AD (2015). Climatic and environmental factors influencing occurrence and distribution of macroalgae – a fjord gradient revisited. Marine Ecology – Progress Series 532: 73-88 

Armitage C, Sjøtun K, Jensen KH (2014). Correlative evidence for competition betweenFucus serratus and the introduced chlorophyte Codium fragile subsp. fragile on the southwest coast of Norway. Botanica Marina 57: 85-97

Husa V, Steen H, Sjøtun K (2014). Historical changes in macroalgal communities in Hardangerfjord (Norway). Marine Biology Research 10: 226-240

Husa V, Kutti T, Ervik A, Sjøtun K, Kupka Hansen P, Aure J (2014). Regional impact from fin-fish farming in an intensive production area (Hardangerfjord, Norway). Marine Biology Research 10: 241-252

Bengtsson MM, Sjøtun K, Lanzén A & Øvreås L (2012). Bacterial diversity in relation to secondary production and succession on surfaces of the kelp Laminaria hyperborea. The ISME Journal 6: 2188-2198

Sjøtun K, Heldal HE, Brakstad, DS (2011). Differential concentration of Technetium-99 (99Tc) in common intertidal molluscs with different food habits. Marine Pollution Bulletin 62: 2420-2426

Brattegard T, Høisæter T, Sjøtun K, Fenchel T & Uiblein F (2011). Norwegian Fjords: from Natural History to Ecosystem Ecology and beyond. Marine Biology Research 7: 421-424 (editorial note).

Eilertsen M, Norderhaug KM & Sjøtun K (2011). Does the amphipod fauna associated to epiphytes on kelp (Laminaria hyperborea) change with depth? Marine Biology Research 7: 224-234

Bengtsson MM, Sjøtun K, Storesund JE& Øvreås L (2011). Utilization of kelp-derived carbon sources by kelp surface-associated bacteria. Aquatic Microbial Ecology 62: 191-199

Heldal HE & Sjøtun K (2010). Technetium-99 (99Tc) in annual growth segments of knotted wrack (Ascophyllum nodosum). Science of the Total Environment 408: 5575-5582

Lorentsen S-H, Sjøtun K & Grémillet D (2010). Multi-trophic consequences of kelp harvest. Biological Conservation 143: 2054-2062

Bengtsson M, Sjøtun K & Øvreås L (2010). Seasonal dynamics of bacterial biofilms on kelp (Laminaria hyperborea). Aquatic Microbial Ecology 60: 71-83

Coyer J, Hoarau G, Sjøtun K & Olsen JL (2008). Being abundant is not enough: a decrease in effective population size over eight generations in a Norwegian population of the seaweed, Fucus serratus. Biology Letters 4: 755-757

Sjøtun K, Husa V & Peña V (2008). Present distribution and possible vectors of introductions of the alga Heterosiphonia japonica (Ceramiales, Rhodophyta) in Europe. Aquatic Invasions 3: 377-394

Husa V, Sjøtun K, Brattenborg N & Lein TE (2008). Changes of macroalgal biodiversity in sublittoral sites in southwest Norway: impact of an introduced species or higher temperature? Marine Biology Research 4: 414-428

Rueness J, Heggøy E, Husa V & Sjøtun K (2007). First report of the Japanese red alga Antithamnion nipponicum (Ceramiales, Rhodophyta) in Norway, an invasive species new to northern Europe. Aquatic invasions 2: 431-434 (Short communication).

Sjøtun K, Eggereide SF & Høisæter T (2007). Grazer-controlled recruitment of the introduced Sargassum muticum (Phaeophyceae, Fucales) in northern Europe. Marine Ecology Progress Series 342: 127-138. 

Husa V & Sjøtun K (2006). Vegetative reproduction in "Heterosiphonia japonica" (Dasyaceae, Ceramiales), an introduced red alga on European coasts. Botanica Marina 49: 191-199

Sjøtun K, Christie H & Fosså JH (2006). The combined effect of canopy shading and sea urchin grazing on recruitment in kelp forest (Laminaria hyperborea). Marine Biology Research 2: 24-32. 

Rinde E & Sjøtun K (2005). Demographic variation in the kelp Laminaria hyperborea along a latitudinal gradient. Marine Biology 146: 1051-1062

Husa V, Sjøtun K & Lein TE (2004). The newly introduced species Heterosiphonia japonica Yendo (Dasyaceae, Rhodophyta): geographical distribution and abundance at the Norwegian southwest coast. Sarsia 89: 211-217

Sjøtun K & Schoschina EV (2002). Gametophytic development of Laminaria spp. (Laminariales, Phaeopyceae) at low temperature. Phycologia 41: 147-152

 

 

The network "Norwegian seaweeds": http://seaweeds.uib.no