SEAWEED MARICULTURE
Seaweed mariculture is the practice of cultivating and harvesting seaweed. It has frequently been developed as an alternative to improve economic conditions of coastal communities and to reduce over-harvesting of natural seaweed beds. Large-scale seaweed mariculture is carried out mostly in Asian countries, where there is a very high demand for seaweed products. Seaweed aquaculture production is dominated by relatively few species: the brown seaweeds, Saccharina and Undaria, and the red seaweeds Porphyra, Kappaphycus and Gracilaria.
Saccharina, Undaria and Porphyra are cultivated in Japan, China and Korea as a food source. Their common names as food products are kombu (saccharina), wakame (undaria) and Nori (Porphyra). Kappaphycus is the main raw material for carrageenan and it is cultivated in Indonesia and Philippines. Gracilaria is the main raw material for agar-agar and it is cultivated in China, Indonesia and Chile.
In Brazil, the commercial cultivation of Kappaphycus alvarezii has been implemented in coastal waters on the southern (Florianopolis), southeastern (Angra dos Reis, Ilha Grande, Ubatuba) and northeastern (Pitimbu) regions. Gracilaria cultivation has been also implemented in Northeastern coast at the villages of Maceio and Flexeiras.
SOCIO-ECONOMIC IMPACT
Seaweed farming helps to preserve coral reefs, by increasing diversity where the algae have been introduced and it also provides added niche for local species of fish and invertebrates.
Farming may be beneficial by increasing the production of herbivorous fishes and shellfish in the area. It is often considered the most environmentally friendly form of aquaculture as it requires no input of fertilizers and does not cause any major physical alterations of the environment.
The relatively simple technology of seaweed farming with few equipments needed, low cost, short time crop, easy handling and easy drying on mats or beach sand, promoted it as a sustainable activity, capable of providing alternative livelihood opportunities for coastal communities in developing countries.
Further, as the farming areas are in intertidal zones, women can safely access seaweed farm locations. As a result, children in these communities have been able to access education, women have the opportunity to empower themselves and families are better able to pay for their food and expenses.
The introduction of seaweed farming to coastal communities has improved the living standards of households, leading to the conclusion that the socio economic impacts of seaweed farming have been, on the whole, positive.
