Please expand it and claim it.
Low, wet, muddy area periodically or continuously flooded by brackish or salt water to a shallow depth, usually characterized by grasses and other low plants (but not trees); land transitional between terrestrial and aquatic systems where saturation with water is the dominant factor controlling plant and animal communities and soils..
Salt marsh is a key habitat of transitional waters lying at the interface between the land and the sea, depending on, and periodically covered by tidal sea water.
Salt marshes are important because...
Salt marsh species
Managed re-alignment. Restoration of salt marsh etc.
Salt marshes are ??? under the Habitats Directive.
- Bird Directive, Habitat Directive, NATURA 2000
- Natural variability in Coastal Ecosystems#Salt marshes
- Salt marsh on Wikipedia
- CoPraNet glossary 
- Chapman, V.J., 1960. Salt Marshes and Salt Deserts of the World. London: Leonard Hill Limited, 392p.
- Chapman, V.J., 1977. Wet Coastal Ecosystems. Amsterdam: Elsevier, 440p.
- Chapman, V.J., 1997. Coastal Vegetation. New York: Pergamon Press, 292p.