Development and objectives of the PHYCOMORPH European Guidelines for the Sustainable Aquaculture of Seaweeds (PEGASUS)

Ecological and economic importance of seaweeds

Seaweeds play a key ecological role in coastal ecosystems, providing habitat for other marine species, protection to coastal communities, bioremediation by removing nutrients in excess and acting as a reservoir for CO₂. The potential of seaweeds for ecosystem management, the production of bioplastics and as feedstock for biofuel production is also being explored. Seaweeds can also be used for a variety of applications: as raw materials for food and nutraceuticals, well-being and cosmetics, animal feed and fertilizers.

Seaweed aquaculture can help address global challenges related to human consumption, health, aquaculture development and management, and the sustainable circular bioeconomy (EC 2018) and blue growth (Figure 1). Additionally, seaweed aquaculture is relevant to the sustainable development objectives of the United Nations by addressing several of its goals (no poverty, zero hunger, gender equality, decent work and economic growth, industry, innovation and infrastructure, responsible consumption and production, climate action and life below water). In order to meet the growing food security challenge, aquaculture and thereby also seaweeds need to be part of the solution to support the future supply of healthy protein to the world in a responsible and environmentally friendly way (O’Shea et al. 2019).

Figure 1:

Seaweed aquaculture to meet the goals of the European bioeconomy strategy (© Michele Barbier, based on EC documentation, 2018, source photos: iStock, © roxyminder #94394792; Fotolia_110024322_Subscription_XXL_© Countrypixel.jpg).

The main producers of seaweed biomass are Asian countries, China, Korea, the Philippines, and Indonesia, which supply 97% of the global seaweed biomass (FAO 2019). The production status in North America and Chile, as well as the initiatives launched in Africa, are briefly presented in the guidelines. European production, which is still mainly based on the harvesting of seaweeds, aims to develop seaweed farming in line with the economic and societal strategies and priorities of the various European countries. Data on seaweed production in the various European countries are insufficient to understand the current dimension of the sector, but European aquaculture started in 1985 and now stands at 1755 tonnes with a value of US$ 377,2000 (FAO 2019). The main cultivated species are the kelps Saccharina latissima and Alaria esculenta, and the green macroalgae Ulva spp. On a smaller scale, the red seaweeds Porphyra/Pyropia spp. and Palmaria palmata, the green seaweed Codium tomentosum, and the kelp species Laminaria digitata are also cultivated. It is clear from this overview that a better understanding of current production in Europe is needed and should include the assessment of both biomass production quality and environmental impact of the whole value chain.

Challenges identified in the European landscape

Through the review of the current situation in Europe in terms of seaweed cultivation and production, food safety and legislation, and details on the status of development in the main producing countries, challenges were identified. Many of them arise from the different stages of seaweed cultivation, from the origin of the cultivars and the domestication of the species of interest to the development and optimization of the cultivation techniques up to the market supply. The most important measure to be undertaken is the necessary assessment of the potentially serious and often irreversible environmental impacts of seaweed aquaculture, prior to cultivation. This includes the physical impact of the cultivation facilities on the ecosystem, the introduction of alien species or genotypes, the risk of dissemination of parasites and pathogens to the wild populations and the preservation of the local biodiversity (Figure 2). The production of the best cultivar according to the market expectations is a second main challenge. Although several regulations and recommendations apply also to seaweeds currently, as reviewed in Figure 3, no specific European legislation exists regarding the aquaculture of seaweeds. Several European laws, regulations and recommendations already consider seaweed-related activities in general, but updates may be necessary at various levels (e.g. for environmental protection and food safety). And an emphasis needs to be placed on the correlations and links between the different regulations and legislation related to seaweed and food safety. The visibility of clear-cut, transparent, coherent governance across Europe will help foster the development of the industry.

Figure 2:

The development of sustainable seaweed aquaculture in Europe faces a number of challenges: market size, potential environmental impact, and preservation of local genetic diversity, the need to intensify research – both fundamental and applied, regulation of food quality, heavy metals or alien species, and cultivation constraints ranging from automation to issues of epiphytism (© Michele Barbier).

Figure 3:

Different European legislation with implications for seaweed aquaculture (© Michele Barbier).

COST action PHYCOMORPH FA1406

Considering that the potential of seaweed cultivation would be a determinant for the future of the European sustainable production of biomass, the European COST Association (www.cost.eu) funded a project involving a group of experts in seaweed growth and reproduction. Its mission was to build a network dedicated to (1) the advance of knowledge in seaweed biology, (2) capacity-building in the seaweed research community and training of early-stage scientists in macroalgal studies and cultivation, and (3) the preparation of guidelines for sustainable aquaculture of seaweeds in Europe. Over 4 years, the network Phycomorph (www.phycomorph.org) gathered more than 350 scientists of the public and private sectors from 20 European countries and eight additional ones from America, Asia and North Africa. The partnership deployed during the Action led to several oral or poster presentations during conferences (EPC6 London, IPC11 Szczecin) and to the publication of 28 collaborative articles, book chapters and books, among which is Research Topics in Frontiers in Plant Science (2015, open access: https://www.frontiersin.org/research-topics/2598/from-the-emergence-of-multicellularity-to-complex-body-architectures-update-and-perspectives-on-the#overview). Notably a special issue of Botanica Marina was dedicated to Phycomorph (Botanica Marina, 2017, vol. 60, issue 2: Phycomorph: macroalgal development and morphogenesis, partly open access), which included reports of progress in the identification of the environmental and cellular (including bacteria) parameters controlling life cycle phase transitions and seaweed morphogenesis (Katsaros et al. 2017, Martins et al. 2017, Weiss et al. 2017) together with a new technique based on infra-red spectrometry to quantify carbohydrate in Ulva blades (Shefer et al. 2017). More methods developed recently on different aspects of macroalgal biology and cultivation were then published in the book Protocols for macroalgae research (Charrier et al. 2018).

In addition to publications, capacity-building through 25 short-term scientific missions strengthened bonds between COST members and promoted the development of new research topics. Sixty students acquired new skills in:

(i) seaweed cultivation, (ii) genomics and transcriptomics, (iii) analytical chemistry and (iv) microscopy and cell biology techniques, all focused on macroalgae, through Training Schools and Workshops organized during the past 4 years.

However, evidence quickly arose that the production sector was too tiny and fragile to be able to fully benefit from the European progress made in fundamental knowledge and cutting-edge techniques. Attempts to boost the transfer of academic knowledge to the farming sector was illustrated in a Phycomorph collaborative viewpoint paper (Charrier et al. 2017). However, for the sector to develop, a broader scope of bottlenecks was to be identified, and then solutions proposed to pass them. Relying on the bonds established during the first 2 years, the network further expanded during the preparation of the guidelines. Experts in seaweed cultivation (fertility, production of juveniles in the hatchery, biomass production from field cultivation, disease, metabolism, genetics and domestication), exploitation (trait definition, biomass conservation, standardization, refinery), research (genetic improvement, cryopreservation, bioprospective) and ethics were contacted throughout the world.

PEGASUS methodology

For 18 months, six coordinators identified based on their complementary expertise, synthesized the contributions of 48 international experts from 20 different countries worldwide to draft the recommendations. In order to always involve a wider community, draft versions have been presented at various international conferences and to several European stakeholder groups: EU Aquaculture Advisory Council (May 2018), Aquaculture Canada 2018 conference, AQUA 2018 (World Aquaculture Society), Annual Scientific Conference of the International Council for the Exploration of the Sea (Sept 2018). PEGASUS was also opened for international public consultation in December 2018 to receive criticism and improve content accuracy and relevance for all stakeholders. Changes in the direction of progress have regularly been made based on feedback from the European Commission through the involvement of the EU Joint Research Center (which maintains an inventory of European seaweed cultivation companies and production methods). Updates were regularly presented to the DG-MARE (European Commission). The guidelines are divided into eight chapters:

Chapter I – Seaweeds as an opportunity to meet human needs; Chapter II – Economic importance of seaweeds; Chapter III – Seaweed production – Cultivation; Chapter IV – Challenges in the seaweed cultivation process; Chapter V – Challenges in market economy and regulation; Chapter VI – Challenges in food safety; Chapter VII – Research programmes to support sustainable development of seaweed aquaculture; Chapter VIII – Conclusion – Summary of recommendations for the sustainable development of seaweed aquaculture in Europe. It provides a multidimensional framework for the sustainable and profitable development of aquaculture. This 200-page document is open access (http://phycomorph.org/pegasus-phycomorph-european-guidelines-for-a-sustainable-aquaculture-of-seaweeds) together with a shorter version reviewing the main recommendations and a flyer. These later documents were designed to ease the reading and understanding of the guidelines for policymakers, industries as well as society.

PEGASUS recommendations

PEGASUS performed both a thorough analysis of the current state of European production and identification of challenges and bottlenecks that currently prevent the development of the seaweed aquaculture sector in Europe, as summarized in the sections above. The aim is to contribute to the development of maritime economic activities while preserving the marine environment. It should be considered as a technical and scientific advice tool provided to all stakeholders.

Inter alia, PEGASUS provides specific details on the regulatory framework that currently applies to the production and consumption of seaweeds as food or food supplements. PEGASUS helps to reveal this multidimensional sector, which has noticeable economic, social and environmental dimensions, and less understandable technological, legal and marketing aspects that also contribute to its development. These guidelines are fully in line with the recommendations of the United Nations guidance document (Cottier-Cook et al. 2016). PEGASUS specifically aims to better understand the current situation in Europe in terms of seaweed cultivation and production, food safety and legislation, with details on the status of development in the main producing countries.

The guidelines also identified what research topics should be prioritized in the future to support the sustainable development of the seaweed industry. The main recommendations are summarized below.

Cultivation and seasonal and geographic variability

Before cultivating a new species, it is necessary to identify its market relevance and the traits of interest. Determining the time needed to make the farm profitable requires a good understanding of all the necessary investments.

The domestication of new species requires a good knowledge of its life cycle: the influence of environmental factors such as temperature, nutrients, salinity and light in the growth dynamics and biomass characteristics must be known to identify optimal growing conditions, biochemical composition or flavor and optimize cultivation effort and cost. Since the beneficial form and constituents of a species can vary according to geographic regions, attention should be paid to the temporal and geographical distribution of characteristics of interest.

The development of seaweed aquaculture involves, in the medium and long term, the expansion of cultivation areas. However, the environmental impact of offshore cultivation is not sufficiently known. Non-intensive farming strategies are recommended until more understanding of the environmental impact is reached. The guidelines call for the assessment of the potential impact of the cultivated species on the local community. Therefore, in order to preserve local genetic diversity, the guidelines recommend that any reproduction events and/or dispersal from farms to the wild populations should be monitored and means must be taken to prevent drastic modification of the biodiversity.

Industrial perspectives

The costs of harvesting, pre-treating and processing raw biomass influence the choice of scenario involving the production systems, both at sea and on land. All these aspects and specifically the choice of species with the desired characteristics (e.g. production of biomass to extract alginates, carrageenans or other compounds for cosmetology) must be considered before setting up a farm.

Mechanization of infrastructure or automated harvesting of seaweeds grown at sea can help producers increase and achieve targeted production yields. Reducing transport times and volumes is also one of the key aspects.

After harvesting, biomass stabilization processes are important. Efficient stabilization alternatives and optimal procedures for preparing biomass for the extraction of high-value components from the production chain will ensure access to seaweed biomass all year round and support the growing demand for bioactive substances. The development of these procedures will create value in the coastal industry and support the sustainable development of the European bio-economy based on the cultivation and processing of seaweed biomass.

Integrated European governance should be implemented

For cultivation process, facilities, reference cooperative technical centers and certification consortium structures should be implemented. For the governance procedures, an integrated system at the national level should bring together experts from technical centers, research institutes, producers, and industries in order to foster collaboration. This would provide support to producers by helping them to obtain funding for investment purposes or to cover damage in the event of vandalism, accidents or natural disasters. Technical reference centers should be set up with expertise to assist local farmers and/or identify suppliers on request at the regional level. The introduction of certification consortium structures for the control of the origin of strains grown at the national level should be considered, as well as the standardization of best practices for seaweed aquaculture across Europe.

The notion of local strains for a specific market requires registered designations of origin. The implementation of tools to ensure the traceability of all culture strains is necessary. In particular, the indicators (such as molecular DNA markers, values for the traits of interest, and some geographical information about the origin of the strain) must be standardized and harmonized across the EU Member States. Certification procedures should be implemented or transferred to existing aquaculture certification centers.

EU-level regulations

Seaweed aquaculture activities must comply with the requirements of the European directives managing the protection and sustainable use of the marine environment (Figure 3).

The main challenges identified in relation to the development of seaweed aquaculture are related to the potential environmental impacts of the production facilities that still need to be adequately evaluated. These potential impacts might conflict with directives protecting, for example, marine biodiversity, managing the maritime space uses and optimization of production sites and supporting the development of an ecosystem-based approach for seaweed aquaculture. One particular concern is the use of alien or locally absent species in aquaculture. Better knowledge on the risk of these species to the environment is needed and better coordination across Europe to harmonize the national lists of invasive alien species of Member State concern is recommended. A list of alien species of economic interest in Europe should be established and their potential impact on the environment evaluated by risk assessment studies.

National aquaculture regulations

The guidelines provide detailed information, at the national level (Denmark, France, Ireland, Norway, Portugal, Scotland, Spain), on the development and main challenges of the seaweed aquaculture sector and seaweed aquaculture related regulations. As for the EU level, for most countries with the exception of a few very specific pieces of legislation, no regulation for seaweed aquaculture is in place and this activity follows the regulatory framework of the other aquaculture activities. The status of development of the sector is very country-specific. Some of the main challenges identified are related to the complex licensing processes, the need for more knowledge on species traits and environmental drivers and public acceptance of the aquaculture activity.

Market

Commercialization, consumer awareness and education, rules to import seaweeds or seaweed products into Europe, are all important issues because they are the suction force of all sectors. Random checks at the borders should be carried out on imported products as well as on domestic products which must comply with Community or National legislation on the different seaweed uses.

The requirement for a complete list of seaweed species authorized as food in Europe

Such a list would facilitate the work of companies in the seaweed sector wishing to introduce new products to the market and would contribute to the compliance with food safety requirements. In addition, the dissemination of this list of species authorized as food would increase public awareness of the use of seaweed as food, as their lack of awareness is currently one of the main obstacles to the marketing of seaweed as a common food product.

Legislation

Legislation on contaminants such as heavy metals and the problems posed by iodine and inorganic arsenic should cover seaweed “as food” and not only “as a food supplement” as is the case in the current legislation (EU recommendation 2018/464). Monitoring and evaluation of harmful components and update threshold values of heavy metals, iodine, arsenic in seaweed can remove trade barriers and provide clear and up-to-date guidelines on the adequate threshold values for different components and their effect on health when seaweeds are consumed. Organic certification exists for cultivated and natural seaweed populations but is supervised by a wide range of organizations, while various certification processes apply in different European countries. Best practices at the European level could guide, advise and homogenize the process.

Consumption of various seaweeds: risk-benefit analyses

Some health benefits of seaweeds are demonstrated, but risk-benefit analyses (including chemical risk assessments: high iodine content, metals, and nutrients) should be performed. To support claims that seaweeds are a nutraceutical, bioactive food or superfood, complementary scientific research and clinical evidence are necessary. Clear information regarding the chemical form of the compounds, the amount and the intake frequency are required. The current work of the European Food Safety Authority (EFSA) on this topic is very timely.

Preservation of seaweeds for food

There is a need to increase knowledge about the effects of post-harvest handling – conservation treatments – on the quality and stability of marine macroalgae (nutrient content, organoleptic properties) for food applications. Best storage should be determined for each species and product, as well as best practices for improving and securing the shelf life of products.

Food market

For downstream preservation/processing, industrial classification codes should be drafted by the producing companies in collaboration with the food authorities. These codes can also be developed in collaboration with EU experts in seaweeds to establish common rules. Finally, although the food market is often trend-oriented, Western consumers need to be educated and encouraged to consider seaweed as food. It is recommended to create a vocabulary to describe the flavor of seaweed, in order to guide consumers’ choice, in terms of taste or nutrients.