Liste des biotopes et milieux floristiques.

Biotope - Typologie Européenne EUNIS

A3.21 - Niveau 4 : Laminaires et algues rouges sur roche infralittorale sous hydrodynamisme modéré
Description
Taxons (Liens actifs si espèces présentes)
Callophyllis laciniata (Hudson) Kütz., 1843, Chondrus crispus Stackh., 1797, Corallina officinalis L., 1758, Corallinaceae Lamouroux, 1812, Cryptopleura ramosa (Hudson) L.Newton, 1931, Delesseria sanguinea (Hudson) J.V.Lamour., 1813, Dilsea carnosa (Schmidel) Kuntze, 1898, Hypoglossum hypoglossoides (Stackh.) F.S.Collins & Hervey, 1917, Membranoptera alata (Hudson) Stackh., 1809, Palmaria palmata (L.) Weber & Mohr, 1805, Phycodrys rubens (L.) Batters, 1902, Plocamium cartilagineum (L.) P.S.Dixon, 1967,
A3.212 - Niveau 5 : Laminaria hyperborea sur roche infralittorale soumise aux courants de marée
Description
Wave exposed to moderately wave exposed, tide-swept bedrock and boulders with Laminaria hyperborea, characterised by a rich under-storey and stipe flora of foliose seaweeds including the brown seaweed Dictyota dichotoma. The kelp stipes support epiphytes such as Cryptopleura ramosa and Phycodrys rubens. At some sites, instead of being covered by red seaweeds, the kelp stipes are heavily encrusted by the ascidian Botryllus schlosseri. Epilithic seaweeds Delesseria sanguinea, Plocamium cartilagineum Heterosiphonia plumosa, Hypoglossum hypoglossoides, Callophyllis laciniata, Kallymenia reniformis, Brongniartella byssoides and crustose seaweeds commonly occur beneath the kelp. The kelp fronds are often covered with growth of the hydroid Obelia geniculata or the bryozoan Membranipora membranacea. On the rock surface, a rich fauna comprising the bryozoan Electra pilosa, the sponge Pachymatisma johnstonia, anthozoans such as Alcyonium digitatum, Sagartia elegans and Urticina felina, colonial ascidians such as Clavelina lepadiformis, the calcareous tubeworm Pomatoceros triqueter and the barnacle Balanus crenatus occur. More mobile species include the gastropod Calliostoma zizyphinum, the crab Cancer pagurus and the echinoderms Asterias rubens and Echinus esculentus. Two variants have been described: Tide-swept kelp forest (unit A3.2121) and tide-swept kelp park (unit A3.2122). Situation: This biotope occurs below Alaria esculenta (Ala) at exposed sites or L. digitata (Ldig.Ldig) at moderately exposed locations. With increasing depth the kelp density diminishes to become tide-swept kelp park (A3.2122).
Taxons (Liens actifs si espèces présentes)
Brongniartella byssoides (Goodenough & Woodward) F.Schmitz, 1893 ( Esp. caract. )
Callophyllis laciniata (Hudson) Kütz., 1843 ( Esp. caract. )
Corallinaceae Lamouroux, 1812 ( Esp. caract. )
Cryptopleura ramosa (Hudson) L.Newton, 1931 ( Esp. caract. )
Delesseria sanguinea (Hudson) J.V.Lamour., 1813 ( Esp. caract. )
Heterosiphonia plumosa (J.Ellis) Batters, 1902 ( Esp. caract. )
Hypoglossum hypoglossoides (Stackh.) F.S.Collins & Hervey, 1917 ( Esp. caract. )
Kallymenia reniformis (Turner) J.Agardh, 1842 ( 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)