Published 2018-10-09

This post is also available in Swedish

Dream of putting more seaweed on our plates

Professor Henrik Pavia, a marine biologist, has studied algae throughout his research career. Now he has developed Sweden’s first commercial seaweed farm (cultivating macroalgae) in the Kosterhavet National Park. This year’s harvest is already in the freezer counters of two major Swedish supermarket chains (Coop and ICA).

‘There’s enormous interest in our seaweed. It’s almost a bit exaggerated,’ Pavia says.

We are sitting in an open motorboat heading out to the Kosterhavet National Park, part of the Koster archipelago in the Skagerrak basin, off Sweden’s west coast. Pavia wants to show us this year’s harvest of sugar kelp (Saccharina latissima, also known as ‘sea belt’). An area of two hectares (some five acres) of it – three big football pitches – is suspended on ropes beneath us from the shiny red buoys. He leans over the rail.

‘See how smooth and fine they are — no fouling.’

Henrik Pavia likes algae. He has devoted himself to them throughout his research life. As a PhD student, he examined their chemical defence substances, seeking to understand how algae defend themselves against animals that feed on them. He sees himself as following a proud Swedish tradition of basic algae research in marine botany, with Carl Adolph Agardh, Carl Skottsberg and Harald Kylin as leading lights. His own interest in diving was another impetus.

‘I got hooked on algae. I was young and had a diving certificate. The algae were fascinating to look at,’ he says.

However, what Pavia has been doing in the past few years is something new. Developing algaculture (seaweed cultivation) on a commercial scale is unprecedented in Sweden. In Asia, seaweed is everyday food; but there, environmental concerns are not always the primary consideration.

The algaculture here, in the Kosterhavet National Park, bears the Swedish KRAV ecolabel for organic production. The algae need no fertilisation; instead, they clean up the sea by removing excess nutrient salts from land runoff along the coasts. This is a rare and efficient ecosystem service.

‘We can’t copy what’s being done in Asia. It doesn’t fit in with our legislation and our view of how to manage ecosystems,’ he says.

Algae are outstandingly nutritious food. They contain vitamins, minerals and healthy omega-3 fatty acids. They also bear the elusive umami flavour that makes other food taste better. The craving for Pavia’s seaweed is therefore hardly surprising.

The algaculture is part of AquaAgri, a research programme that, in five separate projects, has developed new system solutions for more efficient and sustainable food production. The research relates to both agriculture and aquaculture, and fruitful exchanges between agronomists and marine biologists have been strikingly frequent.

‘As an algaculturalist, I have masses to learn from farmers, not least in terms of production systems. We’ve learnt how to get algae to grow like crazy. Now we need to develop the other parts of the chain.’

Achieving large-scale production is not entirely easy. Algae have a complicated lifecycle that Pavia and his colleagues have spent four years learning to control. The spores drift up onto land at the Sven Lovén Centre for Marine Infrastructure at Tjärnö, whose buildings somewhat resemble a hotel complex with windows facing the Bohuslän archipelago. The spores are then sown into ropes that are taken out to sea at appropriate times.

This gives the scientists purely practical problems to manage. How deep should the farms be? When is the best time of year to lay the algae in the sea? How should the algae be stored after the harvest?

‘In the first few years, we harvested by hand and it was extremely arduous. Now we’ve built a barge that can help us. But there are still huge quantities of algae to deal with after the harvest,’ Pavia says.

Although the young Pavia was highly committed to the environment, he chose to study economics.

‘Back then, I already regarded economics as crucial in solving environmental problems. Today that view’s won through on a broad front. I’d read a book on environmental economics and was fascinated by how the economic system was rigged.’

Wanting to change this system, he enrolled at the University of Gothenburg’s School of Business, Economics and Law (Handelshögskolan). The working lad from Biskopsgården took the tram to Handels in Vasagatan, and a culture clash ensued. The yuppie heyday of the 1980s was then in full swing.

‘People had suits with broad shoulders. They carried briefcases and joined investment clubs. Then I came along, with my interest in environmental economics.’

After a year, he dropped out and began studying marine biology. He attended a basic course in marine botany, and has remained in this field.

By the second time we talk, the harvest has been gathered, dried and partially sold. It goes into such products as seaweed burgers, which are marketed as such nationwide. High-class restaurants along the west coast and in Stockholm are also curious about Pavia’s seaweed.

Now, AquaAgri is in its final phase and the results from all five projects will be reported at a closing conference in Stockholm at the end of October.

Pavia believes they have driven research forward over the past four years. Before the summer, an international conference was held at the Tjärnö Laboratory. Some 50–60 leading researchers from all over the world were invited.

‘The guest scientists were surprised at how quickly we got to such a high level. That’s how we’re doing well. We’re truly pioneers of Swedish algaculture.’

But a great deal remains to be done, he says.

‘One thing we’re looking at is integrated cultivation, with algae serving as catch crops for other species — such as mussels. These release ammonia, which is perfect food for algae.’

Another dream is to start algaculture in the Baltic Sea. This would require completely different kinds of seaweed; there, growing sugar kelp is not feasible. The eutrophication in the Baltic Sea, with its excess nutrients, is no disadvantage, Pavia thinks.

‘On the contrary, it’s like a farmer getting the most fertile soil to cultivate.’

Henrik Pavia

Age: 56

Job title: Professor of Marine Biology at the University of Gothenburg.

Work: Grows seaweed on a commercial scale.


Facts about AquaAgri

A research programme in agriculture and aquaculture, AquaAgri has received co-funding of SEK 62 million from Mistra, the Swedish Research Council Formas and the Lantmännen Research Foundation. The programme comprises the following five separate projects.

Perennial Crops. Scientists at the Swedish University of Agricultural Sciences (SLU) have developed perennial wheat and barley relatives that, for example, bind carbon better through their longer root systems. This year, perennial cereal crops withstood the drought significantly better than the ordinary wheat harvest.

Milk on Grass and By-products. Researchers at SLU have studied what happens if cereals and soya are completely excluded from concentrate feeds for dairy cows. The results point to new opportunities for making Swedish agriculture more sustainable, and with this year’s feed shortage their relevance has increased.

Cultivation of Macroalgae. Sweden’s first commercial seaweed farm (growing macroalgae) is in the Kosterhavet National Park. The sugar kelp grown there is KRAV-labelled and is now sold in retail outlets.

Environmentally sustainable farming of European lobster and Atlantic wolffish in the interdisciplinary NOMACULTURE (‘NOvel, high‐quality MArine aquaCULTURE’) project. At the Sven Lovén Marine Infrastructure Centre (Kristineberg station) and the Zoologen building in Gothenburg, aquaculture of species that can contribute to coastal livelihoods is being developed. The farming takes place mostly in recirculating aquaculture systems (RAS), which are environmentally sustainable.

The Wheat Gap. To both boost crop yields and reduce the environmental impact of agriculture, researchers have investigated the difference between the actual harvest farmers achieve and the potential harvest attainable in perfect conditions. Knowing what causes this gap paves the way for increased harvests.

AquaAgri is holding its final conference on 23 October 2018, at IVA Conference Center, Grev Turegatan 16, Stockholm.




Text: Thomas Heldmark