The EU Bioeconomy Strategy aims to support the sustainable growth and development of the EU bio-based sectors while creating jobs, innovation and services. Despite the recognized potential of the algae biomass value chain, significant knowledge gaps still exist regarding the dimension, capability, organization and structure of the algae production in Europe. This study presents and analyses the results of a comprehensive mapping and detailed characterization of the algae production at the European scale, encompassing macroalgae, microalgae, and the cyanobacteria Spirulina. This work mapped 447 algae and Spirulina production units spread between 23 countries, which represents an important addition to the reported number of algae producing countries. More than 50% of these companies produce microalgae and/or Spirulina. Macroalgae production is still depending on harvesting from wild stocks (68% of the macroalgae producing units) but macroalgae aquaculture (land-based and at sea) is developing in several countries in Europe currently representing 32% of the macroalgae production units. France, Ireland, and Spain are the top 3 countries in number of macroalgae production units while Germany, Spain, and Italy stand for the top 3 for microalgae. Spirulina producers are predominantly located in France, Italy, Germany, and Spain. Algae and Spirulina biomass is directed primarily for food and food-related applications including the extraction of high-value products for food supplements and nutraceuticals. Algae production in Europe remains limited by a series of technological, regulatory and market-related barriers. Yet, the results of this study emphasize that the European algae sector has a considerable potential for sustainable development as long as the acknowledged economic, social and environmental challenges are addressed.

Seaweed resources play an increasingly important role in European Blue Growth and Bioeconomy strategies and European production is anticipated to increase dramatically with the continued up-swing of global market interests in seaweed resources. As a consequence, there is a need to ensure the environmental sustainability of future aquaculture activities, as reported in the PEGASUS white paper. The present article summarizes the published PEGASUS guidelines developed in the framework of the COST Action Phycomorph, for the future development of this sector. This includes the advances made in this important arena of applied phycology taking into account scientific, technical, environmental, legal and socioeconomic dimensions. Challenges, bottlenecks and risks are identified and presented with a special focus on production issues regarding productivity, breeding, choice of appropriate cultivars, disease and pests and also the risk of using non-indigenous and invasive species as candidates for cultivation. The barriers for long-term, sustainable exploitation are also examined including harmony with the European “Nutrition and Health Regulations” necessary in order to ensure food safety. The PEGASUS guidelines provide scientific recommendations required to address the above issues and to provide science-based advice to policymakers, managers and industries for the sustainable development of industrial-scale seaweed aquaculture in Europe and beyond.

A comprehensive expert consultation was conducted in order to assess the status, trends and the most important drivers of change in the abundance and geographical distribution of kelp forests in European waters. This consultation included an on-line questionnaire, results from a workshop and data provided by a selected group of experts working on kelp forest mapping and eco-evolutionary research. Differences in status and trends according to geographical areas, species identity and small-scale variations within the same habitat where shown by assembling and mapping kelp distribution and trend data. Significant data gaps for some geographical regions, like the Mediterranean and the southern Iberian Peninsula, were also identified. The data used for this study confirmed a general trend with decreasing abundance of some native kelp species at their southern distributional range limits and increasing abundance in other parts of their distribution (Saccharina latissima and Saccorhiza polyschides). The expansion of the introduced species Undaria pinnatifida was also registered. Drivers of observed changes in kelp forests distribution and abundance were assessed using experts' opinions. Multiple possible drivers were identified, including global warming, sea urchin grazing, harvesting, pollution and fishing pressure, and their impact varied between geographical areas. Overall, the results highlight major threats for these ecosystems but also opportunities for conservation. Major requirements to ensure adequate protection of coastal kelp ecosystems along European coastlines are discussed, based on the local to regional gaps detected in the study.

Macroalgae have played an important role in coastal communities for centuries. In the past, they have been harvested and gathered from shorelines around the world for traditional uses such as food, animal feed and a crude fertilizer (marine manure). Today, seaweeds are used in a multitude of applications with expanding global industries based on hydrocolloids, cosmetics and food supplements, and also as a potential biofuel source. However, of the approximately 10 000 algal species reported to exist, only a small number are commercially utilized. While representing only a small fraction of total global seaweed production, harvesting and gathering 'wild' seaweeds has had, and continues to have, an integral role in many coastal societies, often being intrinsically linked to the cultural identity of those coastal communities. Today, 32 countries actively harvest seaweeds from wild stocks, with over 800 000 t harvested annually from natural beds. It is vitally important that seaweeds are utilized sustainably and that natural resources are effectively managed by coastal communities with vested interests around the world. As the popularity of seaweeds increases and the use of less traditional species with novel applications comes to the fore, it is critically important to make certain that the sustainability of the resource is ensured given the increased pressures of harvesting. Issues exist regarding ownership of the resource and its over-exploitation, and the implementation of environmentally damaging harvesting techniques must be avoided. Resource scientists, managers, conservationists, governments, and other stakeholders need to be proactive in the sustainable management of these vulnerable, yet valuable, resources.

The northern Portuguese coast is a biogeographic transition zone where many macroalgal species have their distribution limits; it is thus a particularly interesting region for investigating species distribution shifts. An updated and complete list of species for this region is not available in spite of its baseline importance for comparative studies with past and present data. Based on new records, literature references, and herbarium data, we provide an updated checklist of the benthic marine algae of the northern Portuguese coast. This checklist includes 346 species: 26 Cyanobacteria, 200 Rhodophyta, 70 Ochrophyta, and 50 Chlorophyta. From these, 21 species are new records for the Portuguese coast (Lyngbya aestuarii, Lyngbya semiplena, Microcoleus acutirostris, Myxosarcina gloeocapsoides, Aiolocolax pulchella, Antithamnion densum, Antithamnion villosum, Antithamnionella spirographidis, Dasya sessilis, Furcellaria lumbricalis, Neosiphonia harveyi, Porphyrostromium boryanum, Chorda filum, Dictyopteris ambigua, Sphacelaria rigidula, Undaria pinnatifida, Vaucheria coronata, Vaucheria velutina, Ulothrix implexa, Ulva scandinavica, and Umbraulva olivascens) and 33 were recorded for the first time in the north of Portugal. Alien species have increased in number and extended their distribution range over the last 10 years in the study area. Distribution shifts of northern cold water species with southern distribution limit in the north of Portugal were not consistent among species.

1. Kelp species are ecosystem engineers in temperate coasts, where they provide valuable services to humans. Evidence of the declines of kelp forests exists from several regions, but their effects on fisheries still need to be elucidated. More effective management strategies for sustainable fisheries require a synthesis of research findings and an assessment of how research could be improved to fill current gaps. 2. This review aimed to: (i) summarize the available evidence on the influence of changes in kelp density and/or area on the abundance and diversity of associated fisheries and (ii) examine how research on kelp-fisheries interactions could better support effective management. 3. Most studies (67%) reported data ascribable, directly or indirectly, to a positive relationship between kelp and fishery-relevant variables, 11% provided evidence of a negative relationship, 15% indicated species-specific findings and the remaining found unclear or 'neutral' relationships. 4. Important shortcomings were identified, including the paucity of experimental studies suitable to test for unequivocal cause-effect relationships, the disproportion between North America, which is well-studied, and other regions and between the large number of fish-based investigations and the small number of those focusing on other commercially important organisms, and the general lack of studies carried out over spatial and temporal scales comparable to those of global processes driving patterns of distribution of both kelps and fisheries. 5. Synthesis and applications. The consistency of most studies in showing a positive kelp-fishery relationship supports the protection of kelp habitats stated by current environmental directives. However, achieving their goals requires that the limitations we detect are addressed through better connections between research, management practice and policy. This would require the following: (i) researchers to combine multiple approaches (large-scale experimental studies and modelling) for the analysis of kelp-fisheries relationships; (ii) funding agencies to provide resources needed to fill the existing gaps; and (iii) researchers and institutions from less studied regions to strengthen collaborations with those from regions where there have been more investigations into kelp-fishery systems. This is essential under present and predicted environmental changes, with the ultimate aim of conserving and allowing the sustainable use of critically important habitats and of fishery resources relying on these.

In this work, microspectrofluorimetry was for the first time applied to the identification of the red organic lakes that are characteristic of the lavish illuminations found in 15(th) century books of hours. Microspectrofluorimetry identified those red paints, ranging from opaque pink to dark red glazes, as brazilwood lakes. An unequivocal characterization was achieved by comparison with reference paints produced following recipes from the medieval treatise The Book on How to Make Colours, and was further confirmed by fiber optic reflectance spectroscopy (FORS). For these treasured cultural objects, microspectrofluorimetry and FORS proved to be the only techniques that could identify, in situ or in microsamples, the chromophore responsible for the pinkish hues: a brazilein-Al(3+) complex. Additionally, a multi-analytical approach provided a full characterization of the color paints, including pigments, additives, and binders. Microspectroscopic techniques, based on infrared and X-ray radiation, enabled us to disclose the full palette of these medieval manuscripts, including the elusive greens, for which, besides malachite, basic copper sulfates were found; Raman microscopy suggested a mixture of brochantite and langite. Infrared analysis proved invaluable for a full characterization of the additives that were applied as fillers or whites (chalk, gypsum, and white lead) as well as the proteinaceous and polysaccharide binders that were found pure or in mixture.

Marginal populations are often geographically isolated, smaller, and more fragmented than central populations and may frequently have to face suboptimal local environmental conditions. Persistence of these populations frequently involves the development of adaptive traits at phenotypic and genetic levels. We compared population structure and demographic variables in two fucoid macroalgal species contrasting in patterns of genetic diversity and phenotypic plasticity at their southern distribution limit with a more central location. Models were Ascophyllum nodosum (L.) Le Jol. (whose extreme longevity and generation overlap may buffer genetic loss by drift) and Fucus serratus L. (with low genetic diversity at southern margins). At edge locations, both species exhibited trends in life-history traits compatible with population persistence but by using different mechanisms. Marginal populations of A. nodosum had higher reproductive output in spite of similar mortality rates at all life stages, making edge populations denser and with smaller individuals. In F. serratus, rather than demographic changes, marginal populations differed in habitat, occurring restricted to a narrower vertical habitat range. We conclude that persistence of both A. nodosum and F. serratus at the southern-edge locations depends on different strategies. Marginal population persistence in A. nodosum relies on a differentiation in life-history traits, whereas F. serratus, putatively poorer in evolvability potential, is restricted to a narrower vertical range at border locations. These results contribute to the general understanding of mechanisms that lead to population persistence at distributional limits and to predict population resilience under a scenario of environmental change.