Status report oktober 2019

Published 02 October 2019

75 talks, 10 popular- and 7 scientific articles, 10 reports and 1 book chapter have been disseminated, and the knowledge platform has contributed to 55 media articles and produced 4 movies. The project educates 6 PhD and 9 MSc-students. 3 prototypes of seaweed cultivation equipment, a model for kelp cultivation potential and a numeric tool for structural design of kelp farms have been developed.

MACROSEA targets industrial macroalgae cultivation in Norway. 

The final "MACROSEA Open Day" will be arranged as a joint seminar together with the new RCN-funded Knowledge platform Norwegian Seaweed Biorefinery Platform (2019-2023) at Royal Garden hotel in Trondheim 27-28 November 2019.

WP1 seedling Biology

A seedlings cultivation protocol for the red algae P. palmata has been optimized by studying the seasonal dependency for fertility, different methods for spore release from fertile tissue and surface disinfection of sorus, and the MSc-thesis «Investigation of important steps in Palmaria palmata cultivation» by R. R. Bøe has been published and a paper by PS Schemedes et al has been submitted. A sea cultivation experiment with Palmaria has been carried out as the first in Norway starting with spore release and attachment on nets, incubation for 3 months and deployment in IMTA in winter (Feb). The plants grew slow during the spring, but in June a high density and blades up to 15 cm were registered. As a measure to improve the quality in the seedling production of Saccharina latissima 11 different methods for seedlings production and deployment were tested in 2018. Sporophytes and gametophytes were seeded on twines and incubated for 2 to 6 weeks before spinning on ropes and deployed, in addition to cultures of gametophytes and microscopic sporophytes that were seeded directly on cultivation ropes using a commercial glue as binder (Forbord et al in press). We have developed image analysis methods for effective estimation of seedling coverage on seeded material before deployment (WP5), a method showing good correlation with frond lengths in sea. 


  • Balasubramaniam M (2017). Veksteksperiment av makroalger med kommersiell interesse; med hovedfokus på Palmaria palmata. MSc-thesis, University of Oslo
  • Bøe RR (2019). Investigation of important steps in Palmaria palmata cultivation. MSc-thesis, NTNU
  • Duarte A (2017). Optimization of seedling production using vegetative gametophytes of Alaria esculenta. MSc-thesis, University of Porto.
  • Forbord S, Steinhovden KB, Rød KK, Handå A., Skjermo J (2018). Cultivation protocol for Saccharina latissima. In: Charrier, B., Wichard, T. & Reddy, C. R. K. (eds.) Protocols for Macroalgae Research. U.S.A.: CRC Press, Taylor & Francis Group, p. 37-59 
  • Forbord S, Steinhovden KB, Solvang T, Handå A, Skjermo J (2019). Effect of seeding methods and hatchery period on sea cultivation of Saccharina latissima (Phaeophyceae): a Norwegian case-study. Journal of Applied Phycology. In press 
  • Schmedes PS, Nielsen MM, Petersen K. New hatchery methods for efficient spore use and seedling production of Palmaria palmata (dulse). J. Applied Phycology. Submitted.
  • Su L, Pang S, Shan T, Li X (2017). Large-scale hatchery of the kelp Saccharina japonica: a case study experience at Lvshun in Northern China, in Journal of Applied Phycology

WP2 Sea Cultivation

A lab experiment has been conducted with nitrogen-saturated and nitrogen-limited juvenile S. latissima (8-12 cm in length) to study N-uptake of nitrate and ammonia (WP2). Results are being analysed and soon ready to be submitted for publication. One MSc-thesis by V.R. Dahlen has been published: "Characterization of the initial ammonium uptake in S. latissima: Possible implications for an IMTA system with intensive salmon farming". A Monitoring programme has been performed with S. latissima. Seeded ropes were deployed at 9 sites in Feb 2017 followed by registrations from Apr to Sep the same year. Chemical analysis of amino acids, heavy metals, CN, internal nitrate, ash and dry matter is complete together with growth and biofouling data, and carbohydrate contentis being analysed. The manuscript «Latitudinal, seasonal and depth-dependent variation in growth, chemical composition and biofouling of cultivated sugar kelp (Saccharina latissima) along the Norwegian coast» is submitted and currently under revision. Two MSc-thesis have been published: "Morfologiske relasjonar til dyrka S. latissima ved tre stasjonar langs Norskekysten" by S. Foldal, and "The effects of variable environmental conditions on growth, nutritional state and protein content in cultivated S. latissima in Norway" by G. E. Brodahl. The results will significantly improve the sugar kelp growth model in SINMOD (WP4). An article has been published in Journal of Aquaculture on variation of biofouling and growth of S. latissima (Matsson et al 2019). A field trial has been conducted on the date of deployment (Feb, Apr, May) of S. latissima related to growth, internal nitrate-N, C/N and fouling in Tromsø. Preliminary results show a difference between the deployment dates in amount of biofouling and growth.


  • Brodahl GE (2018). The effects of variable environmental conditions on growth, nutritional state and protein content in cultivated S. latissima in Norway. MSc-thesis, NTNU
  • Bøe RR (2019). Investigation of important steps in Palmaria palmata cultivation. MSc-thesis, NTNU
  • Dahlen V (2018). Characterization of the initial ammonium uptake in Saccharina latissima: Possible implications for an IMTA system with intensive salmon farming. MSc-thesis, NTNU
  • Foldal S (2018). Morfologiske relasjonar til dyrka S. latissima ved tre stasjonar langs Norskekysten. MSc-thesis, NTNU
  • Forbord S, Matsson S, Brodahl G, Bluhm B, Broch OJ, Handå A, Metaxas A, Skjermo J, Steinhovden KB, Olsen Y. Latitudinal and seasonal variation of growth, chemical content and biofouling of cultivated sugarkelp (Saccharina latissima) along the Norwegian coast. Under review
  • Matsson S, Christie H, Fieler R (2019). Variation in biomass and biofouling of kelp, Saccharina latissima, cultivated in the Arctic, Norway. Aquaculture 506, p 445-452. 
  • Skjermo J (2019). Høsting av havents planter – tang og tare. In: Nye Muligheter for verdiskaping i Norge, Almås K (ed). SINTEF rapport ISBN?                               

WP3 Genetics and disease

Samples of S. latissima for population genetics have been collected along the Norwegian coast and along Sognefjorden in a gradient from the innermost parts to the outer coastal parts, as well as from Hardangerfjord and the coastal parts between the two fjords to study degree of local population connection and gene flow in fjord seascapes. The material has been analysed using microsatellites, and the results are presented in a MSc thesis: «Population genetics of Saccharina latissima (sugar kelp) in Norway» by T. Næss. The results showed that the most isolated fjord populations had a different genetic structure than the coastal populations, while they suggested a good gene flow and little genetic differentiation between coastal populations. This material has been supplemented with more stations and samples, and are now re-analysed.  In the same way, S. latissima from more open coast and more enclosed populations have also been analysed in a study from Scottland, but by using a different method (dd RADseq sequencing) and as part of the work of a PhD-student in Scottland (SAMS) (Thomson et al in prep). These results showed a clear tendency of local adaptation and selection, and a relatively strong genetic differentiation between the coastal populations. A RNA-Library will be created and transcriptional analysis of samples from a common-garden experiment with sugar kelp from Tromsø, Trondheim and Bergen will be done.


  • Thomson A, Visch W, Nylund GM, Pavia H, Sjotun K, Stanley M. Population diversity and structure of Saccharina latissima on the Scottish and Swedish west coast. In prep.
  • Næss T (2018). Analyses of population genetics of Saccharina latissima (sugar kelp) in Norway. MSc-thesis UiB.

WP4 Marine Modeling

Papers on IMTA (Fossberg et al 2018) and on the sugar kelp cultivation potential along the Norwegian coast and the surrounding waters (Broch et al 2019) have been published. In Fossberg et al we combine results from a field study with SINMOD and a kelp growth model while Broch et al is based on results from SINMOD coupled with the kelp growth model. Some of these results are being made available on web as a support tool for kelp cultivators and management. An advanced model for self-shading within kelp cultures has been implemented in SINMOD. This model will bli used with the results from the other WPs (nutrient uptake, fouling, drag) to approach a precise model based estimate for the kelp production potential at a given location.


  • Broch OJ, Alver MO, Bekkby T, Gundersen H, Forbord S, Handå A, Skjermo, J, Hancke K (2019). Kelp cultivation potential in coastal and offshore regions. Frontiers in Marine Science. 
  • Broch OJ, Tiller R, Skjermo J, Handå A (2017). Potensialet for dyrking av makroalger i Trøndelag. SINTEF Ocean OC2017 – A200. ISBN 978-82-14-06099-7.
  • Broch OJ, Skjermo J, Handå A (2016). The potential for large scale cultivation of macroalgae in Møre and Romsdal (in Norwegian: Potensialet for storskala dyrking av makroalger i Møre og Romsdal) SINTEF report. ISBN:978-82-14-06099-7.
  •  Foldal S (2018). Morfologiske relasjonar til dyrka S. latissima ved tre stasjonar langs Norskekysten. MSc-thesis, NTNU 
  • Fossberg J, Forbord S, Broch OJ, Malzahn A, Jansen H, Handå A, Førde H, Bergvik M, Fleddum AL, Skjermo J, Olsen Y (2018). The Potential for Upscaling Kelp (Saccharina latissima) Cultivation in Salmon-Driven Integrated Multi-Trophic Aquaculture (IMTA). Frontiers in Marine Science 5:418

WP5 Seedling, Deployment and Harvest Technology

Adaptations to next generation seaweed rope spinner for in situ use in deployment are being studied. The seeding time/speed (meter seeded rope per day) has been increased 6-10 times in MACROSEA. Work on the R&D requirements for an industrial production line for seedlings is finalized.  See reports about this and automated seeding systems, and an animation of a new production concept for large scale production, SPOKe. Methods for image processing of substrate for quantification of sporophytes (Master thesis) has been developed and tested, together with spore density (Forbord et al, in press). Design elements regarding rope attachment methods have been developed, and a master thesis on a robot for automated deployment and harvesting is completed, resulting in a SPOKe demo.


WP6 Sea Farms

Towing experiments at sea were conducted in 2016 and 2017. Loads and towing velocities were measured. Towing experiments with artificial sugar kelp were conducted at NTNU in 2017. Drag forces were measured and the movement of the models were recorded by an underwater camera. The study is published in the MSc thesis "Design of Artificial Seaweeds for Assessment of Hydrodynamic Properties of Seaweed Farms" by C. Norvik. A study of mechanical properties and morphology of sugar kelp (Saccharina latissima) has been carried out as part of a SINTEF summer student programe (Norvik 2016). In 2018 tests with cultivated sugar kelp were conducted in a closed test facility containing sea water. Towing velocities, drag forces and tensile forces in the rope were measured (Endresen et al in press). Results from the towing tests have been used in FhSim for simulation of a seaweed farm planned to be deployed in exposed environments in Norway in 2020.


  • Endresen PC, Norvik C, Kristiansen D, Birkevold J, Volent Z (2019). Current Induced Drag Forces on Cultivated Sugar Kelp. Proceedings of the ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering OMAE2019 June 9-14, 2019, Glasgow, Scotland. OMAE2019-96375. In press 
  • Norvik C (2017). Design of Artificial Seaweeds for Assessment of Hydrodynamic Properties of Seaweed Farms. MSc-thesis, NTNU 
  • Norvik C (2016) "Design of artificial seaweeds for assessment of hydrodynamic properties of seaweed farms". SINTEF summer student report