Description of biotope or habitat type
Oligochaetes in variable or reduced salinity infralittoral muddy sediment
Habitat (physical) description
|Salinity||Reduced (18-30ppt), Variable (18-35 ppt)|
|Wave exposure||Very sheltered, Extremely sheltered|
|Tidal streams||Moderately strong (1-3 kn), Weak (>1 kn)|
|Substratum||Cohesive muddy sediment, sandy mud|
|Depth Band||0-5 m|
|Other Features||Possibly affected by a high biochemical oxygen demand|
Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.
- Records used to define the biotope (core records)
- Other records assigned to this biotope, marked as 'certain'
- Other records assigned to this biotope, marked as 'uncertain'
- Predicted extent of the level 3 (for sublittoral rock & deep sea) or 4 (for sublittoral sediment) habitat
Reduced or variable salinity muddy and sandy mud sediments characterised by oligochaetes, particularly of the genus Tubificoides or from the group Enchytraeidae. The abundance of the oligochaetes may vary by several orders of magnitude but very few other species will be present. Organic loading and poor water-exchange within the sediment lead to anoxic conditions which may explain the low species richness within this biotope.
This biotope is found towards the edges of tidal channels in estuaries where current velocities allow deposition of silt and the establishment of an infaunal community. The biotope may occur downstream of SMU.LhofTtub, differentiated by the absence of the freshwater species, and adjacent to more mobile and sandier biotopes in the tidal channels.
No temporal data available.
|Taxon||Relative importance of taxon for defining this community (%)||Typical abundance - SACFOR scale||Typical abundance - (count per m2)||% of core records where taxon was recorded|
|Tubificoides pseudogaster||2||40||1-20 %|
|Diptera larva||11||Abundant||61||21-40 %|