Seaweed
Seaweed or macroalgae refers to several species of macroscopic, multicellular, marine algae. The term includes some types of red, brown, and green macroalgae. Marine algae species such as kelps provide essential nursery habitat for fisheries and other marine species and thus protect food sources; ocean algae species from seaweeds to planktons play a vital role in carbon capture, producing up to 90 percent of the planet's oxygen. Understanding these roles provides guiding principles for conservation and sustainable use of seaweeds to take precedence over industrial exploitation. Mechanical dredging of kelp, for instance, destroys the resource and dependent fisheries. Certain species of seaweed are valuable for nutrition, biomedicine, bioremediation, and other uses.
Edible seaweed
In some parts of Asia, nori 海苔 (in Japan), zicai 紫菜 (in China), and gim 김 (in Korea), sheets of the dried red alga "Porphyra" are used in soups or to wrap sushi or onigiri. "Chondrus crispus" (commonly known as Irish moss) is another red alga used in producing various food additives, along with Kappaphycus and various gigartinoid seaweeds.