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Concept: [Ascophyllum nodosum] on full salinity mid eulittoral rock in the eunishabitats vocabulary

Concept URI http://eunis.eea.europa.eu/eunishabitats/A1.3141
Preferred label [Ascophyllum nodosum] on full salinity mid eulittoral rock
Definition Bedrock, stable boulders and cobbles in the mid-eulittoral zone of moderately exposed to extremely sheltered shores, in fully marine conditions, characterised by a dense canopy of the wrack [Ascophyllum nodosum]. Another wrack [Fucus vesiculosus] may in some places co-dominate the canopy. The hydroid [Dynamena pumila] can form colonies on the wracks [F. vesiculosus] and [Fucus serratus]. Variations in the ratio of [A. nodosum] and [F. vesiculosus] in the overlying canopy have little effect on the under-storey species. Beneath the canopy are a diverse array of filamentous and foliose red seaweeds, including [Mastocarpus stellatus, Chondrus crispus, Gelidium pusillum] and coralline crusts. The filamentous red seaweed [Polysiphonia lanosa] is usually present on [A. nodosum] as an epiphyte. A few green seaweeds including [Cladophora rupestris] and [Enteromorpha] spp. are also present in moderate to low densities. On the bedrock and boulders beneath the seaweed canopy is a fauna including the barnacle [Semibalanus balanoides], the limpet [Patella vulgata], tube-forming spirorbid polychaetes and the anemone [Actinia equina]. The latter can be present in damp cracks and crevices. On and among the seaweeds are mobile species including the winkles [Littorina littorea] and [Littorina obtusata], the whelk [Nucella lapillus] or even the crab [Carcinus maenas]. At the top of the [A. nodosum] zone there might be the occasional presence of the olive green lichen [Verrucaria mucosa]. Situation: This biotope is usually found between the wrack [Fucus spiralis] (Fspi) and [F. serratus] dominated biotopes (Fserr), although on some shores a narrow zone of [F. vesiculosus] (Fves) may occur immediately above the [A. nodosum]. With increasing wave exposure the [A. nodosum] canopy is replaced by [F. vesiculosus] (FvesB; Fves). Asc.FS can occur on more exposed shores, where there is localised shelter. Temporal variation: [A. nodosum] can reach an age of 25 years on sheltered shores and the communities are, once established, usually very stable. [F. vesiculosus] or [F. serratus] can occur in patches where the [A. nodosum] has been removed.
Notation A1.3141
Status Valid
Status Modified 2014-01-31
Accepted Date 2014-01-31
Not Accepted Date
Has broader
Has exact match