Biodiversity in the European Seas
This article acts about the biodiversity in the European Seas. We refer to reports (publish date: 31 may 2002) of the ‘European Environmental Agency’ (EAA), in which each Sea is treated closely with a large attention for the marine biodiversity. The contents of these reports are reflected with the indication of the most relevant information.
The North Sea
The North Sea is a shallow sea (average depth: 90 m) with a surface area of 750 000 km². It is rather a young ecosystem formed by the flooding of a landmass some 20 000 years ago. Its coast and waters are still being colonized by new species from the Atlantic.
As main influences on the North Seas ecosystem are considered: fisheries, eutrophication, offshore industry, maritime traffic, industry and tourism.
The strong coupling between benthic and pelagic communities in the shallow parts of the sea makes it extremely productive and one of the most productive areas in the world, with a wide range of plankton, fish, seabirds and benthic communities. The North Sea is one of the world’s most important fishing grounds. The sea is also rich in oil and gas. Many human activities have an impact on the biodiversity of the North Sea. The marine ecosystems are under intense pressure from fishing, fish farming, kelp harvesting, invading species, nutrient input, recreational use, habitat loss and climate changes; most notable are the effects of fisheries and eutrophication.
The policy conducted in the North Sea has several objectives, from nature protection (discussed conventions/agreements are OSPAR, ICES, ASCOBANS and the Bonn Convention, Trilateral Wadden Sea Cooperation, North Sea Conference, EU Birds and Habitats Directives and Bern Convention) to protection of marine resources (ASCOBANS, the EU Common Fisheries Policy (CFP)).
Furthermore, there are several national, international and non-governmental organization initiatives to assess environmental quality in the North Sea area. The most important are: the ‘continuous plankton recorder’ (CPR), BioMar an the ‘Joint assessment and monitoring programme’ (JAMP).
In the ‘EEA report’ an overview is given of the most important physical, biological and exploitation characteristics, the main threats to biodiversity and the policies at work (nature protection and protection of marine resources by restrictions on fishing and hunting) in the North Sea.
The Baltic Sea
The Baltic Sea is the largest (surface area: 370 000 km²) brackish water system in the world. The shallow sounds between Sweden and Denmark provide a limited water exchange with the North Sea. It takes 25-35 years for all the water in the Baltic to be replenished by water from the North Sea and beyond.