Vassdragsreguleringers virkning på fjorder
Research report
Permanent lenke
http://hdl.handle.net/11250/112823Utgivelsesdato
1984Metadata
Vis full innførselSamlinger
- Fisken og havet (1958- ) [700]
Sammendrag
Natural freshwater discharge to Norwegian fjords is characterized by low
runoff during winter when precipitation is stored as snow and ice, and a
marked peak in the discharge due to snow melting in spring. Hydroelectric
power production causes a modified runoff pattern with increasing freshwater
discharge during winter and reduced flow in spring.
The effects of runoff regulations on physical and biological properties of fjords
are considered on basis of available litterature. Documented physical effects
include changes in salinity, modified current systems and changes in temperature
caused by altered mixing depth following a regulation. Oxygen levels of
the deeper layers in fjords with shallow sills may be altered. The possibility
of changes in the vertical transport of nutrients to the euphotic layer is
discussed. Notes are made on changes in temperature, nutrient supply and
material load from regulated rivers.
In light of these physical changes, possible biological implications are discussed
though biological data are insufficient. The differences in characteristics
among fjords are stressed, with special emphasis on varying influence by
the outer coastal waters.
Utgiver
HavforskningsinstituttetSerie
Fisken og havet1984-03