WATER QUALITY AND SUSTAINABLE AQUACULTURE: LINKS AND IMPLICATIONS

- In the last years there has been a steady growth in the development of aquaculture farms due to the increased demand of cultured species for consumption. One of the by-products of aquaculture is the creation of specific environmental problems related to intensive production and unsustainable farm expansion, leading to a boom and burst behaviour of aquaculture industries.

- Examples are the increasing occurrence of toxic red tides and the consequent incidence of diarrhetic and paralytic shellfish poisoning in southern European countries in the early nineties, or the permanent alteration of natural habitats in Latin America. Therefore, aquaculture and local water quality (WQ) are closely linked. The large inputs of nutrients and chemicals and the release of wastes into the environment may favour toxic algae blooms and induce bottom anoxia and eutrophication, especially where the carrying capacity of the receiving domain is limited (e.g., bays and semi-enclosed waterbodies. In turn, low aquaculture production rates may result from the appearance and spreading of diseases propitiated by a poor WQ.