Concept
Littoral sediment
| URI | http://vocab.nerc.ac.uk/collection/M21/current/JNCCMNCR00000274/1/ | |
|---|---|---|
| Within Vocab | Marine Habitat Classification for Britain and Ireland Version 15.03 | |
| Alternative Labels | LS | |
| Definition | Littoral sediment includes habitats of shingle (mobile cobbles and pebbles), gravel, sand and mud or any combination of these which occur in the intertidal zone. Littoral sediment is defined further using descriptions of particle sizes - mainly gravel (16-4 mm), coarse sand (4-1 mm), medium sand (1-0.25 mm), fine sand (0.25-0.063 mm) and mud (less than 0.063 mm) and various admixtures of these (and coarser) grades - muddy sand, sandy mud and mixed sediment (cobbles, gravel, sand and mud together). Littoral sediments support communities tolerant to some degree of drainage at low tide and often subject to variation in air temperature and reduced salinity in estuarine situations. Very coarse sediments tend to support few macrofaunal species because these sediments tend to be mobile and subject to a high degree of drying when exposed at low tide. Finer sediments tend to be more stable and retain some water between high tides, and therefore support a greater diversity of species. Medium and fine sand shores usually support a range of oligochaetes, polychaetes, and burrowing crustaceans, and even more stable muddy sand shores also support a range of bivalves. Very fine and cohesive sediment (mud) tends to have a lower species diversity, because oxygen cannot penetrate far below the sediment surface. A black, anoxic layer of sediment develops under these circumstances, which may extend to the sediment surface and in which few species can survive. Some intertidal sediments are dominated by angiosperms, e.g. eelgrass (Zostera noltii) beds on the mid and upper shore of muddy sand flats, or saltmarshes which develop on the extreme upper shore of sheltered fine sediment flats. | |
| Date | 2018-02-13T18:46:01 | |
| Identifier | SDN:M21::JNCCMNCR00000274 | |
| Note | accepted | |
| Is Version Of | JNCCMNCR00000274 | |
| version | 1 | |
Alternate Formats
Other formats for this page:
RDF/XML Turtle JSON-LDAlternate Profiles
Other views of this page:
Alternate Profiles ?Different Media Types (HTML, text, RDF, JSON etc.) and different information model views, profiles, are available for this resource.
NVS html view ? Default NVS html view.
