Seaweed resources of the Baltic Sea, Kattegat and German and Danish North Sea coasts

• Published in: Botanica marina Vol. 63; no. 1; pp. 61 - 72
• Main Authors: Weinberger, Florian, Paalme, Tiina, Wikström, Sofia A.
• Format: Journal Article
• Language: English
• Published: Berlin De Gruyter 2020; Walter de Gruyter GmbH
• Subjects: Algae; Aquaculture; Coasts; Cultivation; Ecological effects; Eutrophication; eutrophication mitigation; Exploitation; Fertilizers; Fish; Fish culture; Furcellaria lumbricalis; Nutrients; Saccharina latissima; seaweed aquaculture; seaweed harvesting; Seaweeds; Substrata; North Sea; Baltic Sea
• ISSN: 0006-8055; 1437-4323; 1437-4323
• DOI: 10.1515/bot-2019-0019

Due to low salinity and lack of hard substrata, the Baltic Sea and Kattegat area and German and Danish North Sea coasts are characterized by a relatively low diversity of seaweeds. At the same time the areas are severely eutrophicated, which has caused extensive shifts in macroalgal communities toward opportunistic species. Unattached seaweed communities dominated by , which have been a resource for hydrocolloid production since the 1940s, have been severely reduced due to eutrophication and unsustainable harvesting and are nowadays only exploited commercially in Estonia. On the other hand, the biomass of opportunistic seaweeds of various red, green and brown algal genera has increased. They cause ecological problems, are a nuisance on many tourist beaches and constitute at the same time a potential bioresource that is so far only exploited to a limited extent for production of energy and fertilizer. Commercial seaweed cultivation is largely focused on and still very limited, but is currently being expanded as a compensation measure for sea-based fish aquaculture. Also land-based seaweed cultivation is primarily employed for recycling of nutrients in tank animal aquaculture, but in most cases so far only on an experimental scale.