5: Seaweeds from an Italian Coastal Lagoon: From ‘Waste Material’ to Commercially Valuable Marine Resources

Marine seaweeds, characterised by high-valued bioactive compounds, are used worldwide for several applications, including human food, animal feed, pharmaceutics and cosmetics, bioplastics, agricultural fertilisers, biofuels, and others. Seaweed production can be carried out through different approaches, from on-land or sea-based cultivation to the harvesting of wild stocks. The latter can be of particular importance in the case of seasonal algal over-proliferations, often caused by eutrophic conditions associated with intensive human industrial activities, and which wreak havoc with ecosystem functioning and hinder economic activities. In Europe, Italy experiences seaweed blooms in several coastal basins, such as the Lagoon of Venice and the Lagoon of Orbetello (Tuscany). Here, the proliferating seaweed represents a disturbance to the natural ecosystem and to local business and touristic activities. These biomasses hold no economic value in the country and are systemically removed and disposed of. Re-purposing the biomass to produce seaweed-derived commercial goods would provide benefits for the environment and local economic activities while promoting a sustainable business within a Circular Economy framework and contribute to the UN Sustainable Development Goals number 12 (‘Responsible consumption and production’), and number 14 (‘Life under water’), among others.