Vol. 10, Issue 1, Part A (2026)

The seaweed aquaculture has become the highest growing sector of global aquaculture, which presents a sustainable route to fulfilling the increasing resource demands whilst alleviating the strain on terrestrial agriculture and marine life. The review is based on synthesizing world and national data on seaweed production, trade and policies based on international agencies such as FAO, UNCTAD, and the World Bank and national sources such as ICAR-CMFRI and the Department of Fisheries, which refer to the last 20 years (2000-2022). The world seaweed harvested in the year 2021 was 35.2 million tons, of which more than 98 percent was produced in Asian countries, mainly China and Indonesia. The global market is estimated at about USD 17 billion in 2021 but will rise to close to USD 85 billion by 2026 because of the increasing demand of renewable, bio-based and environmentally sustainable products. Although this has been increased, commercial cultivation continues to be highly concentrated with eight dominant species predominantly Laminaria japonica and Eucheuma spp. producing 93.7% volume of the world output.

The seaweed segment is now broadening out of the food and hydrocolloid market into high-value market segments like bio-stimulants, methane-reducing livestock feed additives, bioplastics, alternative protein, nutraceuticals and biofuels. Bio-stimulants made out of seaweed in and of themselves form USD 1 billion market, which is expected to grow to USD 1.87 billion by year 2030. Nevertheless, international and national development is progressively limited by climate-related stressors such as increasing sea temperatures, reduced growing season, and diminished output.

The sector has been underutilized in India, even though it has 7517km of coastline, 844 reported seaweed species, and 317 of the possible sites of cultivation occupying 23970 hectares. The national production dropped by almost 20 percent, 34,922 tons in 2009 and 27,937 tons in 2018, as a result of mass mortality of farmed Kappaphycus alvarezii after 2013 and overharvesting of natural agarophyte stocks. As a result, processing industries in the country are running at a low level and India is mainly importing sodium alginate mainly the Chinese industries which are also supplying about 92 percent of the total imports. To curb this situation, the Government of India has put in place ₹640 crore in the Pradhan Mantri Matsya Sampada Yojana (PMMSY) with a production goal of 1.12 million tons by 2025.

To reach this target, the development of large-scale mariculture as an alternative to the wild harvest and the financial assistance of research in the field of the diversification of their species and the creation of strains with high yields is mandatory. The fortification of the seaweed industry will not only increase industrial independence and livelihood in the coast but also lead directly to the UN Sustainable Development Goals via climate change and carbon capture, coastal cleanup and the larger-scale transformation of the sea. Seaweed farming can be described as a bio engine of the green economy, which can sustainably address the needs of the environment and the economy at the same time.