The importance of kelp microbiomes
Date of publication: Apr 12, 2023

Hello! I am Sofie, a PhD student at the University of Ghent, currently working on unravelling the role Laminaria ochroleuca’s microbiome plays in its growth and development.

Laminaria ochroleuca, also known as the golden kelp, is a temperate brown seaweed species, mainly found in the coastal waters of Europe ranging from the UK to Morocco (1,2). It plays an important role in rocky shore ecosystems by providing food and habitat for many marine organisms (2, 3). 

Photo of juvenile Laminaria ochroleuca at Aqualvor, Portugal.

Sadly enough, like many other marine organisms, Laminaria ochroleuca is facing a range of threats due to climate change. The rising sea temperatures are one of the main threats causing these kelp populations to decline off the coasts of Northern Africa and Southern Europe (1, 3). Alongside climate change related threats, many human activities such as pollution and overfishing also cause a lot of damage to these kelp forests (1).

The microbiome of Laminaria ochroleuca plays an important role in the development and health of this kelp species and is often overlooked in marine conservation and management strategies. However, it is known that increased temperatures can cause microbial dysbiosis, which is a disruption in the microbiome. This can contribute to the health decline these kelp populations are experiencing (4).  

Understanding the complex interactions between Laminaria ochroleuca, its microbiome and the changing environment is crucial for effective management and conservation strategies. Within RESTORESEAS one of our goals is to unravel these interactions!

Photos of mature Laminaria ochroleuca taken during a previous sampling campaign in Normandy, France.

At the University of Ghent we have been isolating bacteria and analysing bacterial communities found on Laminaria ochroleuca. Additionally we have started setting up experiments comparing nearly axenic kelp (without microbiome) with kelp that have been supplied with extra bacteria.

In March 2023, we travelled with a few colleagues of the UGent (Prof. Olivier De Clerck, Willem Stock & I) to the Centre of Marine Sciences of the Algarve (CCMAR) in Faro, where they have valuable experience and knowledge on kelp cultivation and microbiomes. We met with researchers Aschwin Hillebrand Engelen and Neusa Martins with whom we had very helpful conversations on how to continue with our research. They made us feel very welcomed and also showed us around in their laboratory and marine research station. Furthermore, during this trip we went to visit Aqualvor, a sustainable fish farm, where we sampled some kelp to take back to Ghent for further research!

Written by Sofie Peeters, University of Ghent


  1. Franco J.N., Tuya F., Bertocci I., et al. (2017). The ‘golden kelp’ Laminaria ochroleuca under global change: Integrating multiple eco-physiological responses with species distribution models. Journal of Ecology. 106(1);47-58. 10.1111/1365-2745.12810.
  2. Smale D., Wernberg T., Yunnie A., Vance T., (2014). The rise of Laminaria ochroleuca in the Western English Channel (UK) and comparisons with its competitor and assemblage dominant Laminaria hyperborea. Marine Ecology. 36;1033-1044. 10.1111/maec.12199.  
  3. Straßer F., Barreto L., Kaidi S., et al. (2022). Population level variation in reproductive development and output in the golden kelp Laminaria ochroleuca under marine heat wave scenarios. Frontiers in Marine Science. 9. 943511. 10.3389/fmars.2022.943511.
  4. Egan S., Gardiner M. (2016) Microbial Dysbiosis: Rethinking Disease in Marine Ecosystems. Frontiers in Microbiology. 7. 10.3389/fmicb.2016.00991.