Reducing environmental impacts of coastal aquaculture.

GESAMP

Reducing environmental impacts of coastal aquaculture.

Autores

Descripción

There have been substantial socio-economic benefits arising from the expansion of coastal aquaculture. However, in some coastal regions, this has caused significant ecological changes. 2. The type and scale of any ecological change associated with coastal aquaculture development will depend on the method of aquaculture, the level of production and the physical, chemical, and biological characteristics of the coastal area. Ecological change has been associated with the large-scale production of bivalves and seaweeds and the release of dissolved and particulate waste from fish, shrimp, and bivalve culture. Destruction of productive wetland habitats has resulted in the disturbance of wildlife and uncontrolled introductions and transfers have altered or impoverished the biodiversity of the receiving ecosystem. Some ecological change, such as the impact of organic waste on the seabed ecosystem, can limit production. 3. The indiscriminate use of bioactive compounds, including pesticides and antibiotics, has caused concern about their release into the aquatic environment. The health implications of the use of chemicals and the consumption of seafood grown in contaminated waters are problems of growing concern, especially in relation to intoxication by phycotoxins and infectious diseases such as typhoid fever, cholera, and hepatitis. 4. Some of the ecological and socio-economic problems encountered are due to the market failure to reflect the true cost of resource depletion and environmental change. The solution to this problem requires policy intervention at national and local level, particularly in regard to the issues of common property rights and economic incentives and deterrents needed to minimize environmental change. 5. Sustainable coastal aquaculture requires adequate consideration of the interactions among the social, economic and ecological changes.