|The Wadden Sea Wetlands: a multi-jurisdictional challenge|
Sustaining the World"s Wetlands : Setting Policy and Resolving Conflicts
toon extra info.
by Richard Smardon
|New York, NY : Springer-Verlag New York|
|Trefwoorden (cab)||wetlands / landgebruik / ecologie / wadden|
|Hoofdstuk uit boek|
|Toelichting (Engels)||Since 1600 the surface area of the Dutch Wadden Sea has decreased by successive reclamation of salt marshes. In 1933 the Zuiderzee (3,200 km2) was closed off from the Wadden Sea causing an increase in tidal range and current velocities in the remaining parts. In 1969 the Lauwerzee (91 km2) was closed off and turned into a freshwater lake. Dredging in harbors and shipping routes as well as extraction of sand and shells became common practice and contributed to turbidity of the Wadden Sea. Discharge of nitrogen and phosphorus into the western Wadden Sea increased manifold since 1950 causing an increase in phytoplankton production, duration of phytoplankton blooms, and intertidal macrozoobenthic biomass. Fisheries changed drastically since the 1930s. Fishing in the Zuiderzee herring came to an end shortly after closing off the Zuiderzee|