Re: The Role of Sustainable Fisheries and Aquaculture for Food Security and Nutrition - E-consultation to set the track of the study

Nurul Istiqomah Indonesia
13.05.2013

Aquaculture Effluent: How to natural treatment

Dillution system of waste treatment will impact  Eutrophication in coastal and river area.

The impact of dillution system are  eutrophication of the water surrounding coastal and rivers areas. Fish excretion and fecal wastes combine with nutrients released from the breakdown of excess feed to raise nutrient levels well above normal, creating alga blooms. In Indonesia contaminated waste generated from industries, sewage, agriculture, aquaculture, etc. Once the resulting algal blooms die, they settle to the bottom where their decomposition depletes the oxygen. Before they die, however, there is the possibility that algal toxins are produced, the example is red tides. Although any species of phytoplankton can benefit from an increased nutrient supply, certain mplesspecies are noxious or even toxic to other marine organisms and to humans. The spines of some diatoms  can irritate the gills of fish, causemple is exang decreased production or even death8. More importantly, blooms ("red tides") of certain species such as Chattonella marina often produce biological toxins that can kill other organisms. Neurotoxins produced by several algal species can be concentrated in filter-feeding bivalves such as mussels and oysters, creating a serious health risk to people consuming contaminated shellfish.

Intensive Farming system   depend on a diet of artificial feed in pellet form. This feed is broadcast onto the surface of the water, and is consumed by the fish as it settles through the water column. Because not all the feed is eaten, a great deal of feed can reach the bottom where it is eaten by the benthos or decomposed by microorganisms. This alteration of the natural food web structure can significantly impact the local environment.The waste could be minimalization with natural management, like Moringa olifeira seed, Sargassum plagyophyllum, shellfish, ,polyculture with trophic level system, probiotic, etc

Dr. Nurul Istiqomah

From: Indonesia