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From the installation of the pipe. 
Photo: Arne Berge
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Controlled upwelling

 In Lysefjorden a collection of freshwater (from the outlet of a hydropower plant) is used to force controlled upwelling of nutrient rich deep water. The water is lead through a pipe (34 metres). This simple construction allows the scientists to live studies of the ecosystem in a grand scale fjord laboratory.    

The freshwater is discarded below the nutricline and the buoyant freshwater mixes with the nutrient rich water as it ascends into the euphotic zone. The upwelled nutrient rich water intrudes the layer below the pycnocline and the nutrients are now readily available for primary producers

The controlled upwelling of nutrient rich deep water in the Lysefjord enables large scale (10-20 km2) studies on how nutrient availability affect ecosystems. 

An increase in primary production and a threefold increase in standing stock of phytoplankton within the area of influence were demonstrated in 2004-2005. 

In an aquaculture context, the controlled upwelling may enhance the production of seaweed and suspension feeding bivalves but may also promote environmental restoration and detoxification of mussels.




The outlet of Lysebotn plant