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ATLANTIC SEAWEED - An every day sight that we take for granted.



Seaweed or macroalgae refers to several species of macroscopic, multicellular, marine algae.

The term includes some types of red, brown, and green macroalgae. Seaweed may provide excellent opportunities for its industrial exploitation as they could be a source of multiple compounds (i.e. polysaccharides, proteins and phenols) with applications such as food and animal feed, pharmaceuticals or fertilizers.

Seaweed has a variety of purposes, for which it is farmed or foraged from the wild.

At the beginning of 2011, Indonesia produced 3 million tonnes of seaweed and surpassed the Philippines as the world's largest seaweed producer. By 2011, the production was estimated to have reached 10 million tonnes.






Seaweed is consumed by coastal people, particularly in East Asia, e.g. Japan, China, Korea, Taiwan, and Southeast Asia, e.g. Brunei, Singapore, Thailand, Burma, Cambodia, Vietnam, Indonesia, Philippines, and Malaysia, and also in South Africa, Belize, Peru, Chile, the Canadian Maritimes, Scandinavia, South West England, Ireland, Wales, California, and Scotland.

In Asia, Gim (Korean food) (
, Korea), nori (海苔, Japan), zicai (紫菜, China) are sheets of dried Porphyra used in soups, sushi wrap or onigiri (rice balls). Chondrus crispus (commonly known as 'Irish moss' or carrageenan moss) is another red alga used in producing food additives, along with Kappaphycus and gigartinoid seaweed. Porphyra is a red alga used in Wales to make laver. Laverbread, made from oats and the laver, is a popular dish there. In northern Belize, edible seaweed are mixed with milk, nutmeg, cinnamon, and vanilla to make a common beverage affectionately called "dulce" (or "sweet").

Seaweed are also harvested or cultivated for the extraction of alginate, agar and carrageenan, gelatinous substances collectively known as hydrocolloids or phycocolloids. Hydrocolloids have attained commercial significance as food additives. The food industry exploits their gelling, water-retention, emulsifying and other physical properties. Agar is used in foods such as confectionery, meat and poultry products, desserts and beverages and moulded foods. Carrageenan is used in salad dressings and sauces, dietetic foods, and as a preservative in meat and fish products, dairy items and baked goods.

The development of seaweed as an alternative and sustainable source of food and animal feed ingredients depends on the sustainability of the natural resource of raw biomass and on moving the process of feed development from laboratory to industrial scale.




Open ocean seaweed farms can improve water quality. Many of the dangers the ocean faces today, specifically ocean acidification, can be mitigated by increasing the amount of seaweed grown. The World Bank predicts that achieving a global production of 500 million tons of seaweed by 2050 would absorb 10 million tons of nitrogen, which is 30 percent of the nitrogen estimated to enter the ocean, and 15 million tons of phosphorus, which is 33 percent of the total phosphorus produced through fertilizers, from the ocean. Rising carbon dioxide levels, the leading cause of ocean acidification, can also be mitigated through seaweed. Seaweed has an amazing carbon dioxide uptake and storage; kelp takes in five times more carbon than most land-based plants. That same seaweed production of 500 million tons would consume 135 million tons of carbon, which is 3.2 percent of the carbon added to seawater each year from greenhouse gas emissions.


Increasing seaweed aquaculture production may open the door for a more efficient form of renewable energy: biomass. The many environmental benefits of growing seaweed make it a unique solution to the renewable energy challenge. In addition, seaweed’s potential to be cultivated in seawater may lessen the growing competition for access to land and freshwater. In the United States, biomass-derived energy accounted for roughly five percent of the country’s energy in 2015, making biomass the largest form of renewable energy. The ARPA-E estimated that seaweed cultivation in the United States has the potential to reach 500 million tons of red and brown algae, providing more energy than over 23 billion gallons of gasoline. However, current seaweed production has not yet reached the scale necessary to drive down costs and encourage a seaweed biomass industry.


Seaweed’s ability to break down environmental pollutants also makes its development a top priority for the aquaculture industry. Fish farming comes with many environmental challenges, mainly feed consumption. Some of the concerns about open-sea fisheries come from the fear that excess feed and fish feces negatively impact the surrounding ecosystem. A solution to mitigate the excess organic and inorganic deposits left from farms is integrated multi-trophic aquaculture. Adding crustaceans and aquatic plants to finfish operations can turn fish byproducts into inputs for another species. According to research from SINTEF, the nitrogen emissions from salmon farming can be reused by kelp and help the kelp plant grow to a significantly larger size.

Safe and sustainable, seaweed aquaculture might be the much-needed solution to the question of responsibly feeding the world’s growing population.





Seaweed can be made into straws to replace plastic.








IN ABUNDANCE - Seaweed as a bed on the Australian coast.



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