Coastal waters
From a geographical and ecological point of view, coastal waters are both coastal areas of the open sea and waters that are reciprocally connected to the open sea and are enclosed on several sides by land.
definition
The term coastal waters thus encompasses very different water areas. The delimitation to the high seas is arbitrary for some coastal waters, by setting a distance to the baseline , the water edge at low tide .
The distinction between inner coastal waters and inland inland waters close to the coast is qualitatively possible:
- The water level of coastal waters is at sea level or follows its fluctuations, for example tides .
- Inner coastal waters have a constant or at least frequent influx of seawater.
Classification
The classification of coastal waters has acquired legal significance through the EU Water Framework Directive (WFD) . The classification is also important for the scientific evaluation and comparison of the ecological development of different coasts.
The classification of coastal waters takes into account both the spatial relationship of the various water bodies to the open sea, the coast and inland waters, as well as the chemical aspect of the salt content, scientifically referred to as salinity .

Classification according to spatial characteristics
- Open coastal waters roughly correspond to the territorial sea of shipping.
- Inner coastal waters extend landward side of the front coastline, are often only by a tidal inlet connected to the open sea:
-
Transitional waters are transitional forms between flowing waters and coastal waters
- Estuaries with a catchment area of at least 10 km² on tidal coasts
- From a nautical point of view, the Wadden Sea is one of the inner coastal waters, but ecologically it is considered separately.
Classification according to the nature of the water bed
- rocky
- sandy
- muddy
Classification according to salinity
- euhalin - salinity corresponds to the ocean
- polyhalin - salinity not much lower than in the ocean, example: Belt Sea as part of the western Baltic Sea
- mesohalin
- oligohalin - very low salinity, mainly inner coastal waters with large amounts of fresh water such as the lagoon.
See also
Web links
- Uwe Selig, Dirk Schories & Hendrik Schubert: Report on the research project: "Testing the classification approach Mecklenburg-Western Pomerania (inner coastal waters) under the conditions of Schleswig-Holstein and extending the approach to the outer coast". Coastal water classification of the German Baltic Sea according to EU WFD, Part B: Inner coastal waters of Schleswig-Holstein (PDF) (833 kB)
- LAWA-AO RaKon Monitoring Part B, Working Paper I: Water types / reference conditions / class boundaries, as of November 12, 2006, see Tab. 8: Water types in transitional and coastal waters in Germany (PDF file; 236 kB)