⌘K
Biotope - Typologie Européenne EUNIS
A3.21 - Niveau 4 : Laminaires et algues rouges sur roche infralittorale sous hydrodynamisme modéré
Description
Infralittoral rock subject to moderate wave exposure, or moderately strong tidal streams on more sheltered coasts. On bedrock and stable boulders there is typically a narrow band of kelp Laminaria digitata in the sublittoral fringe which lies above a Laminaria hyperborea forest and park. Associated with the kelp are communities of seaweeds, predominantly reds and including a greater variety of more delicate filamentous types than found on more exposed coasts (A3.11). The faunal component of the understorey is also less prominant than in A3.11.
Taxons (Liens actifs si espèces présentes)
A3.216 - Niveau 5 : Laminaria hyperborea sur paroi rocheuse verticale modérément exposée
Description
This unit is found on moderately exposed coasts in moderately strong to weak tidal streams generally in 0-20m water depth. It is characterised by the kelp Laminaria hyperborea, the soft coral Alcyonium digitatum and crinoid Antedon bifida. This biotope is relatively species poor when compared to similar biotopes in more exposed environments e.g. unit A3.117. The urchin Echinus esculentus may be frequently observed grazing the vertical rock face. This biotope may have 2 sub-biotopes. One is characterised by the frequent occurrence of the sea squirt Clavelina lepadiformis and the red seaweeds Phycodrys rubens and Cryptopleura ramosa. The brown seaweed Dictyota dichotoma may also be frequent in this sub-biotope. The second sub-biotope is more species poor than the previous one and is characterised by the common occurrence of Alcyonium digitatum, which is only occasional in the other variant.
Situation: Open rocky coasts in northern Britain, particularly North Sea coasts.
Taxons (Liens actifs si espèces présentes)
Corallinaceae Lamouroux, 1812 ( Esp. caract. )
Cryptopleura ramosa (Hudson) L.Newton, 1931 ( Esp. caract. )
Delesseria sanguinea (Hudson) J.V.Lamour., 1813 ( Esp. caract. )
Henricia sp. ( Esp. caract. )
Phycodrys rubens (L.) Batters, 1902 ( Esp. caract. )
Plocamium cartilagineum (L.) P.S.Dixon, 1967 ( Esp. caract. )
Cryptopleura ramosa (Hudson) L.Newton, 1931 ( Esp. caract. )
Delesseria sanguinea (Hudson) J.V.Lamour., 1813 ( Esp. caract. )
Henricia sp. ( Esp. caract. )
Phycodrys rubens (L.) Batters, 1902 ( Esp. caract. )
Plocamium cartilagineum (L.) P.S.Dixon, 1967 ( Esp. caract. )
Analyse Ecologie du milieu (En fonction des espèces présentes)