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Environmental problems associated
with aquaculture
Those environmental problems that are often associated with aquaculture
are:
The occurrance of oxygen
deficient bottoms
These problems are commonly associated with the cultivation of fish.
Modern fish farms are very intensive, are monokultured
and usually run on a large scale, while demanding the addition of
resources from a large area, on both land and sea. These resources
comprise fodder pellets, broods, spawn, chemicals and energy. Fodder
pellets are usually made of fish that have been captured in other
maritime areas and agricultural products, while chemicals are used
to try and keep the fish well and healthy. Many of these resources
are not utilized fully by the fish and pass straight through the farm
and into the sea. Waste from fish farms is composed av excrement,
waste food and chemicals.
The most obvious short term effect of intensive farming
is the release of suspended material and nutritive salts. The surroundings
areas are effected to varying degrees depending on the farms location,
production volumes, cultivation techniques and if processing takes
place at the same location.
Environmental effects can be reduced by a collection
of measures, such as changing the composition of the fodder, collection
and reuse of waste products, by combining cultivation methods (integration)
and by using food that is found naturally in the water.
For mussel and algae cultivation, the circumstances
are different and the problems are not as immense. Because no extra
food or chemicals are supplied, the problem of illness and the the
supply of nutritive salts is eliminated. There is much research being
conducted around mussel and algae farming and it is believed that
they can even have a positive effect on the environment.
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