Traditional Farming of Gracilaria Seaweed in Indonesia

Farming of Gracilaria Seaweed in Indonesia is still use traditional method, or extention methode. This method is appropriate in Indonesia because there are much extensive area for Gracilaria farming pond. Traditional method is using less input as well so reduce negative impact to environment.

 

Supplies of seed stocks are sourced from the wild, from crops obtained in other ponds or from nursery-reared cuttings. Ponds are generally located in areas not exposed to strong prevailing winds, near sources of freshwater and seawater. Usually pond depth is kept at 30-40 cm and water is exchanged every 2-3 days. Salinity is adjusted by freshwater additions while expected seasonal temperature regimes can be modified by pond depth (deeper ponds in warmer areas or seasons). Mineral, especially nitrate and phosphates can be added for seaweed growth. Stocking densities are 5-6 tonnes per ha-1. After 30-35 days of growth in summer and 40-45 days in winter, harvesting is undertaken removing one third to half of the total biomass. Annual production figures of about 34 tonnes per ha-1 have been reported for this production system.